Substances or energies, for example heat or light, which when introduced into the air, water, or land threaten life or health of individuals or ECOSYSTEMS.
Any substance in the air which could, if present in high enough concentration, harm humans, animals, vegetation or material. Substances include GASES; PARTICULATE MATTER; and volatile ORGANIC CHEMICALS.
An agricultural fungicide and seed treatment agent.
Acrolein is an unsaturated aldehyde (C3H4O), highly reactive, toxic and naturally occurring compound that can be found in certain foods, tobacco smoke and is produced as a result of environmental pollution or industrial processes.
A major group of unsaturated cyclic hydrocarbons containing two or more rings. The vast number of compounds of this important group, derived chiefly from petroleum and coal tar, are rather highly reactive and chemically versatile. The name is due to the strong and not unpleasant odor characteristic of most substances of this nature. (From Hawley's Condensed Chemical Dictionary, 12th ed, p96)
Hydrocarbon compounds with one or more of the hydrogens replaced by CHLORINE.
The exposure to potentially harmful chemical, physical, or biological agents in the environment or to environmental factors that may include ionizing radiation, pathogenic organisms, or toxic chemicals.
Industrial products consisting of a mixture of chlorinated biphenyl congeners and isomers. These compounds are highly lipophilic and tend to accumulate in fat stores of animals. Many of these compounds are considered toxic and potential environmental pollutants.
A chemical by-product that results from burning or incinerating chlorinated industrial chemicals and other hydrocarbons. This compound is considered an environmental toxin, and may pose reproductive, as well as, other health risks for animals and humans.
Cytoplasmic proteins that bind certain aryl hydrocarbons, translocate to the nucleus, and activate transcription of particular DNA segments. AH receptors are identified by their high-affinity binding to several carcinogenic or teratogenic environmental chemicals including polycyclic aromatic hydrocarbons found in cigarette smoke and smog, heterocyclic amines found in cooked foods, and halogenated hydrocarbons including dioxins and polychlorinated biphenyls. No endogenous ligand has been identified, but an unknown natural messenger with a role in cell differentiation and development is suspected.
Chemical compounds which pollute the water of rivers, streams, lakes, the sea, reservoirs, or other bodies of water.
Contamination of the air, bodies of water, or land with substances that are harmful to human health and the environment.
The unstable triatomic form of oxygen, O3. It is a powerful oxidant that is produced for various chemical and industrial uses. Its production is also catalyzed in the ATMOSPHERE by ULTRAVIOLET RAY irradiation of oxygen or other ozone precursors such as VOLATILE ORGANIC COMPOUNDS and NITROGEN OXIDES. About 90% of the ozone in the atmosphere exists in the stratosphere (STRATOSPHERIC OZONE).
Elimination of ENVIRONMENTAL POLLUTANTS; PESTICIDES and other waste using living organisms, usually involving intervention of environmental or sanitation engineers.
Organic compounds in which mercury is attached to a methyl group.
The monitoring of the level of toxins, chemical pollutants, microbial contaminants, or other harmful substances in the environment (soil, air, and water), workplace, or in the bodies of people and animals present in that environment.
The products of chemical reactions that result in the addition of extraneous chemical groups to DNA.
Substances or organisms which pollute the water or bodies of water. Use for water pollutants in general or those for which there is no specific heading.
A liver microsomal cytochrome P-450 monooxygenase capable of biotransforming xenobiotics such as polycyclic hydrocarbons and halogenated aromatic hydrocarbons into carcinogenic or mutagenic compounds. They have been found in mammals and fish. This enzyme, encoded by CYP1A1 gene, can be measured by using ethoxyresorufin as a substrate for the ethoxyresorufin O-deethylase activity.
Organometallic compounds which contain tin and three alkyl groups.
A potent mutagen and carcinogen. It is a public health concern because of its possible effects on industrial workers, as an environmental pollutant, an as a component of tobacco smoke.
Particles of any solid substance, generally under 30 microns in size, often noted as PM30. There is special concern with PM1 which can get down to PULMONARY ALVEOLI and induce MACROPHAGE ACTIVATION and PHAGOCYTOSIS leading to FOREIGN BODY REACTION and LUNG DISEASES.
1,2-Benzphenanthrenes. POLYCYCLIC COMPOUNDS obtained from coal tar.
An insecticide and herbicide that has also been used as a wood preservative. Pentachlorphenol is a widespread environmental pollutant. Both chronic and acute pentachlorophenol poisoning are medical concerns. The range of its biological actions is still being actively explored, but it is clearly a potent enzyme inhibitor and has been used as such as an experimental tool.
Gases, fumes, vapors, and odors escaping from the cylinders of a gasoline or diesel internal-combustion engine. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed & Random House Unabridged Dictionary, 2d ed)
Chlorinated hydrocarbons containing heteroatoms that are present as contaminants of herbicides. Dioxins are carcinogenic, teratogenic, and mutagenic. They have been banned from use by the FDA.
Substances which pollute the soil. Use for soil pollutants in general or for which there is no specific heading.
Carcinogenic substances that are found in the environment.
An element with atomic symbol Cd, atomic number 48, and atomic weight 114. It is a metal and ingestion will lead to CADMIUM POISONING.
Compounds that contain two halogenated benzene rings linked via an OXYGEN atom. Many polybrominated diphenyl ethers are used as FLAME RETARDANTS.
Nitrogen oxide (NO2). A highly poisonous gas. Exposure produces inflammation of lungs that may only cause slight pain or pass unnoticed, but resulting edema several days later may cause death. (From Merck, 11th ed) It is a major atmospheric pollutant that is able to absorb UV light that does not reach the earth's surface.
A group of condensed ring hydrocarbons.
The presence of contaminants or pollutant substances in the air (AIR POLLUTANTS) that interfere with human health or welfare, or produce other harmful environmental effects. The substances may include GASES; PARTICULATE MATTER; or volatile ORGANIC CHEMICALS.
A highly toxic, colorless, nonflammable gas. It is used as a pharmaceutical aid and antioxidant. It is also an environmental air pollutant.
Materials applied to fabrics, bedding, furniture, plastics, etc. to retard their burning; many may leach out and cause allergies or other harm.
Toxic, volatile, flammable liquid hydrocarbon byproduct of coal distillation. It is used as an industrial solvent in paints, varnishes, lacquer thinners, gasoline, etc. Benzene causes central nervous system damage acutely and bone marrow damage chronically and is carcinogenic. It was formerly used as parasiticide.
A highly volatile inhalation anesthetic used mainly in short surgical procedures where light anesthesia with good analgesia is required. It is also used as an industrial solvent. Prolonged exposure to high concentrations of the vapor can lead to cardiotoxicity and neurological impairment.
Exposure of the female parent, human or animal, to potentially harmful chemical, physical, or biological agents in the environment or to environmental factors that may include ionizing radiation, pathogenic organisms, or toxic chemicals that may affect offspring. It includes pre-conception maternal exposure.
Industrial chemicals which have become widespread environmental pollutants. Each aroclor is a mixture of chlorinated biphenyls (1200 series) or chlorinated terphenyls (5400 series) or a combination of both (4400 series).
A cadmium halide in the form of colorless crystals, soluble in water, methanol, and ethanol. It is used in photography, in dyeing, and calico printing, and as a solution to precipitate sulfides. (McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed)
Materials incorporated mechanically in plastics (usually PVC) to increase flexibility, workability or distensibility; due to the non-chemical inclusion, plasticizers leach out from the plastic and are found in body fluids and the general environment.
Four fused benzyl rings with three linear and one angular, that can be viewed as a benzyl-phenanthrenes. Compare with NAPHTHACENES which are four linear rings.
Organic compounds containing carbon and hydrogen in the form of an unsaturated, usually hexagonal ring structure. The compounds can be single ring, or double, triple, or multiple fused rings.
The science of controlling or modifying those conditions, influences, or forces surrounding man which relate to promoting, establishing, and maintaining health.
Metals with high specific gravity, typically larger than 5. They have complex spectra, form colored salts and double salts, have a low electrode potential, are mainly amphoteric, yield weak bases and weak acids, and are oxidizing or reducing agents (From Grant & Hackh's Chemical Dictionary, 5th ed)
Chemical substances that are foreign to the biological system. They include naturally occurring compounds, drugs, environmental agents, carcinogens, insecticides, etc.
Chemicals used to destroy pests of any sort. The concept includes fungicides (FUNGICIDES, INDUSTRIAL); INSECTICIDES; RODENTICIDES; etc.
Exogenous agents, synthetic and naturally occurring, which are capable of disrupting the functions of the ENDOCRINE SYSTEM including the maintenance of HOMEOSTASIS and the regulation of developmental processes. Endocrine disruptors are compounds that can mimic HORMONES, or enhance or block the binding of hormones to their receptors, or otherwise lead to activating or inhibiting the endocrine signaling pathways and hormone metabolism.
A polychlorinated pesticide that is resistant to destruction by light and oxidation. Its unusual stability has resulted in difficulties in residue removal from water, soil, and foodstuffs. This substance may reasonably be anticipated to be a carcinogen: Fourth Annual Report on Carcinogens (NTP-85-002, 1985). (From Merck Index, 11th ed)
Substances that increase the risk of NEOPLASMS in humans or animals. Both genotoxic chemicals, which affect DNA directly, and nongenotoxic chemicals, which induce neoplasms by other mechanism, are included.
Biphenyl compounds which are extensively brominated. Many of these compounds are toxic environmental pollutants.
The exposure to potentially harmful chemical, physical, or biological agents by inhaling them.
The chemical alteration of an exogenous substance by or in a biological system. The alteration may inactivate the compound or it may result in the production of an active metabolite of an inactive parent compound. The alterations may be divided into METABOLIC DETOXICATION, PHASE I and METABOLIC DETOXICATION, PHASE II.
Chemical agents that increase the rate of genetic mutation by interfering with the function of nucleic acids. A clastogen is a specific mutagen that causes breaks in chromosomes.
Tests of chemical substances and physical agents for mutagenic potential. They include microbial, insect, mammalian cell, and whole animal tests.
A nucleoside consisting of the base guanine and the sugar deoxyribose.
Exchange of substances between the maternal blood and the fetal blood at the PLACENTA via PLACENTAL CIRCULATION. The placental barrier excludes microbial or viral transmission.
Naturally occurring complex liquid hydrocarbons which, after distillation, yield combustible fuels, petrochemicals, and lubricants.
A soft, grayish metal with poisonous salts; atomic number 82, atomic weight 207.19, symbol Pb. (Dorland, 28th)
Benzene derivatives that include one or more hydroxyl groups attached to the ring structure.
A group of compounds that has the general structure of a dicarboxylic acid-substituted benzene ring. The ortho-isomer is used in dye manufacture. (Dorland, 28th ed)
An array of tests used to determine the toxicity of a substance to living systems. These include tests on clinical drugs, foods, and environmental pollutants.
Induction and quantitative measurement of chromosomal damage leading to the formation of micronuclei (MICRONUCLEI, CHROMOSOME-DEFECTIVE) in cells which have been exposed to genotoxic agents or IONIZING RADIATION.
A superfamily of hundreds of closely related HEMEPROTEINS found throughout the phylogenetic spectrum, from animals, plants, fungi, to bacteria. They include numerous complex monooxygenases (MIXED FUNCTION OXYGENASES). In animals, these P-450 enzymes serve two major functions: (1) biosynthesis of steroids, fatty acids, and bile acids; (2) metabolism of endogenous and a wide variety of exogenous substrates, such as toxins and drugs (BIOTRANSFORMATION). They are classified, according to their sequence similarities rather than functions, into CYP gene families (>40% homology) and subfamilies (>59% homology). For example, enzymes from the CYP1, CYP2, and CYP3 gene families are responsible for most drug metabolism.
A silver metallic element that exists as a liquid at room temperature. It has the atomic symbol Hg (from hydrargyrum, liquid silver), atomic number 80, and atomic weight 200.59. Mercury is used in many industrial applications and its salts have been employed therapeutically as purgatives, antisyphilitics, disinfectants, and astringents. It can be absorbed through the skin and mucous membranes which leads to MERCURY POISONING. Because of its toxicity, the clinical use of mercury and mercurials is diminishing.
A trace element that plays a role in glucose metabolism. It has the atomic symbol Cr, atomic number 24, and atomic weight 52. According to the Fourth Annual Report on Carcinogens (NTP85-002,1985), chromium and some of its compounds have been listed as known carcinogens.
Liquid perfluorinated carbon compounds which may or may not contain a hetero atom such as nitrogen, oxygen or sulfur, but do not contain another halogen or hydrogen atom. This concept includes fluorocarbon emulsions and fluorocarbon blood substitutes.
The status during which female mammals carry their developing young (EMBRYOS or FETUSES) in utero before birth, beginning from FERTILIZATION to BIRTH.
A disturbance in the prooxidant-antioxidant balance in favor of the former, leading to potential damage. Indicators of oxidative stress include damaged DNA bases, protein oxidation products, and lipid peroxidation products (Sies, Oxidative Stress, 1991, pxv-xvi).
The relationship between the dose of an administered drug and the response of the organism to the drug.
Any member of the class of enzymes that catalyze the cleavage of the substrate and the addition of water to the resulting molecules, e.g., ESTERASES, glycosidases (GLYCOSIDE HYDROLASES), lipases, NUCLEOTIDASES, peptidases (PEPTIDE HYDROLASES), and phosphatases (PHOSPHORIC MONOESTER HYDROLASES). EC 3.
A large lobed glandular organ in the abdomen of vertebrates that is responsible for detoxification, metabolism, synthesis and storage of various substances.
The contamination of indoor air.
The N-acetyl derivative of CYSTEINE. It is used as a mucolytic agent to reduce the viscosity of mucous secretions. It has also been shown to have antiviral effects in patients with HIV due to inhibition of viral stimulation by reactive oxygen intermediates.
Air pollutants found in the work area. They are usually produced by the specific nature of the occupation.
Collection, analysis, and interpretation of data about the frequency, distribution, and consequences of disease or health conditions, for use in the planning, implementing, and evaluating public health programs.
A large group of cytochrome P-450 (heme-thiolate) monooxygenases that complex with NAD(P)H-FLAVIN OXIDOREDUCTASE in numerous mixed-function oxidations of aromatic compounds. They catalyze hydroxylation of a broad spectrum of substrates and are important in the metabolism of steroids, drugs, and toxins such as PHENOBARBITAL, carcinogens, and insecticides.
Compounds that accept electrons in an oxidation-reduction reaction. The reaction is induced by or accelerated by exposure to electromagnetic radiation in the spectrum of visible or ultraviolet light.
Liquids that dissolve other substances (solutes), generally solids, without any change in chemical composition, as, water containing sugar. (Grant & Hackh's Chemical Dictionary, 5th ed)
Either of the pair of organs occupying the cavity of the thorax that effect the aeration of the blood.
Liquid chromatographic techniques which feature high inlet pressures, high sensitivity, and high speed.
A transferase that catalyzes the addition of aliphatic, aromatic, or heterocyclic FREE RADICALS as well as EPOXIDES and arene oxides to GLUTATHIONE. Addition takes place at the SULFUR. It also catalyzes the reduction of polyol nitrate by glutathione to polyol and nitrite.
Relating to the size of solids.
A broad class of substances containing carbon and its derivatives. Many of these chemicals will frequently contain hydrogen with or without oxygen, nitrogen, sulfur, phosphorus, and other elements. They exist in either carbon chain or carbon ring form.
The consequences of exposing the FETUS in utero to certain factors, such as NUTRITION PHYSIOLOGICAL PHENOMENA; PHYSIOLOGICAL STRESS; DRUGS; RADIATION; and other physical or chemical factors. These consequences are observed later in the offspring after BIRTH.
An increase in the rate of synthesis of an enzyme due to the presence of an inducer which acts to derepress the gene responsible for enzyme synthesis.
Injuries to DNA that introduce deviations from its normal, intact structure and which may, if left unrepaired, result in a MUTATION or a block of DNA REPLICATION. These deviations may be caused by physical or chemical agents and occur by natural or unnatural, introduced circumstances. They include the introduction of illegitimate bases during replication or by deamination or other modification of bases; the loss of a base from the DNA backbone leaving an abasic site; single-strand breaks; double strand breaks; and intrastrand (PYRIMIDINE DIMERS) or interstrand crosslinking. Damage can often be repaired (DNA REPAIR). If the damage is extensive, it can induce APOPTOSIS.
Molecules or ions formed by the incomplete one-electron reduction of oxygen. These reactive oxygen intermediates include SINGLET OXYGEN; SUPEROXIDES; PEROXIDES; HYDROXYL RADICAL; and HYPOCHLOROUS ACID. They contribute to the microbicidal activity of PHAGOCYTES, regulation of signal transduction and gene expression, and the oxidative damage to NUCLEIC ACIDS; PROTEINS; and LIPIDS.
The total process by which organisms produce offspring. (Stedman, 25th ed)
Respiratory tract diseases are a broad range of medical conditions that affect the nose, throat, windpipe, and lungs, impairing breathing and oxygen uptake, including asthma, chronic obstructive pulmonary disease (COPD), pneumonia, bronchitis, influenza, tuberculosis, and sleep apnea.
A chemical reaction in which an electron is transferred from one molecule to another. The electron-donating molecule is the reducing agent or reductant; the electron-accepting molecule is the oxidizing agent or oxidant. Reducing and oxidizing agents function as conjugate reductant-oxidant pairs or redox pairs (Lehninger, Principles of Biochemistry, 1982, p471).
A large or important municipality of a country, usually a major metropolitan center.
An agency in the Executive Branch of the Federal Government. It was created as an independent regulatory agency responsible for the implementation of federal laws designed to protect the environment. Its mission is to protect human health and the ENVIRONMENT.
The qualitative or quantitative estimation of the likelihood of adverse effects that may result from exposure to specified health hazards or from the absence of beneficial influences. (Last, Dictionary of Epidemiology, 1988)
Naturally occurring or synthetic substances that inhibit or retard the oxidation of a substance to which it is added. They counteract the harmful and damaging effects of oxidation in animal tissues.
An infant during the first month after birth.
Measurable and quantifiable biological parameters (e.g., specific enzyme concentration, specific hormone concentration, specific gene phenotype distribution in a population, presence of biological substances) which serve as indices for health- and physiology-related assessments, such as disease risk, psychiatric disorders, environmental exposure and its effects, disease diagnosis, metabolic processes, substance abuse, pregnancy, cell line development, epidemiologic studies, etc.
Elements of limited time intervals, contributing to particular results or situations.
A tripeptide with many roles in cells. It conjugates to drugs to make them more soluble for excretion, is a cofactor for some enzymes, is involved in protein disulfide bond rearrangement and reduces peroxides.
Experimental devices used in inhalation studies in which a person or animal is either partially or completely immersed in a chemically controlled atmosphere.
Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.
The measurement of an organ in volume, mass, or heaviness.
Carbon monoxide (CO). A poisonous colorless, odorless, tasteless gas. It combines with hemoglobin to form carboxyhemoglobin, which has no oxygen carrying capacity. The resultant oxygen deprivation causes headache, dizziness, decreased pulse and respiratory rates, unconsciousness, and death. (From Merck Index, 11th ed)
The phenomenon whereby compounds whose molecules have the same number and kind of atoms and the same atomic arrangement, but differ in their spatial relationships. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed)
Closed vesicles of fragmented endoplasmic reticulum created when liver cells or tissue are disrupted by homogenization. They may be smooth or rough.
Established cell cultures that have the potential to propagate indefinitely.
Inbred C57BL mice are a strain of laboratory mice that have been produced by many generations of brother-sister matings, resulting in a high degree of genetic uniformity and homozygosity, making them widely used for biomedical research, including studies on genetics, immunology, cancer, and neuroscience.
Elements, compounds, mixtures, or solutions that are considered severely harmful to human health and the environment. They include substances that are toxic, corrosive, flammable, or explosive.
An organochlorine pesticide, it is the ethylene metabolite of DDT.
The motion of air currents.
The status of health in urban populations.
Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.
The state of the ATMOSPHERE over minutes to months.
Acidic water usually pH 2.5 to 4.5, which poisons the ecosystem and adversely affects plants, fishes, and mammals. It is caused by industrial pollutants, mainly sulfur oxides and nitrogen oxides, emitted into the atmosphere and returning to earth in the form of acidic rain water.
Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control (induction or repression) of gene action at the level of transcription or translation.
The vapor state of matter; nonelastic fluids in which the molecules are in free movement and their mean positions far apart. Gases tend to expand indefinitely, to diffuse and mix readily with other gases, to have definite relations of volume, temperature, and pressure, and to condense or liquefy at low temperatures or under sufficient pressure. (Grant & Hackh's Chemical Dictionary, 5th ed)
The span of viability of a cell characterized by the capacity to perform certain functions such as metabolism, growth, reproduction, some form of responsiveness, and adaptability.
Nitric acid (HNO3). A colorless liquid that is used in the manufacture of inorganic and organic nitrates and nitro compounds for fertilizers, dye intermediates, explosives, and many different organic chemicals. Continued exposure to vapor may cause chronic bronchitis; chemical pneumonitis may occur. (From Merck Index, 11th ed)
RNA sequences that serve as templates for protein synthesis. Bacterial mRNAs are generally primary transcripts in that they do not require post-transcriptional processing. Eukaryotic mRNA is synthesized in the nucleus and must be exported to the cytoplasm for translation. Most eukaryotic mRNAs have a sequence of polyadenylic acid at the 3' end, referred to as the poly(A) tail. The function of this tail is not known for certain, but it may play a role in the export of mature mRNA from the nucleus as well as in helping stabilize some mRNA molecules by retarding their degradation in the cytoplasm.
Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.
Inorganic oxides of sulfur.
A variation of the PCR technique in which cDNA is made from RNA via reverse transcription. The resultant cDNA is then amplified using standard PCR protocols.
The atmospheric properties, characteristics and other atmospheric phenomena especially pertaining to WEATHER or CLIMATE.
One of the mechanisms by which CELL DEATH occurs (compare with NECROSIS and AUTOPHAGOCYTOSIS). Apoptosis is the mechanism responsible for the physiological deletion of cells and appears to be intrinsically programmed. It is characterized by distinctive morphologic changes in the nucleus and cytoplasm, chromatin cleavage at regularly spaced sites, and the endonucleolytic cleavage of genomic DNA; (DNA FRAGMENTATION); at internucleosomal sites. This mode of cell death serves as a balance to mitosis in regulating the size of animal tissues and in mediating pathologic processes associated with tumor growth.
The intracellular transfer of information (biological activation/inhibition) through a signal pathway. In each signal transduction system, an activation/inhibition signal from a biologically active molecule (hormone, neurotransmitter) is mediated via the coupling of a receptor/enzyme to a second messenger system or to an ion channel. Signal transduction plays an important role in activating cellular functions, cell differentiation, and cell proliferation. Examples of signal transduction systems are the GAMMA-AMINOBUTYRIC ACID-postsynaptic receptor-calcium ion channel system, the receptor-mediated T-cell activation pathway, and the receptor-mediated activation of phospholipases. Those coupled to membrane depolarization or intracellular release of calcium include the receptor-mediated activation of cytotoxic functions in granulocytes and the synaptic potentiation of protein kinase activation. Some signal transduction pathways may be part of larger signal transduction pathways; for example, protein kinase activation is part of the platelet activation signal pathway.
Inorganic oxides that contain nitrogen.
A deoxyribonucleotide polymer that is the primary genetic material of all cells. Eukaryotic and prokaryotic organisms normally contain DNA in a double-stranded state, yet several important biological processes transiently involve single-stranded regions. DNA, which consists of a polysugar-phosphate backbone possessing projections of purines (adenine and guanine) and pyrimidines (thymine and cytosine), forms a double helix that is held together by hydrogen bonds between these purines and pyrimidines (adenine to thymine and guanine to cytosine).
Identification of proteins or peptides that have been electrophoretically separated by blot transferring from the electrophoresis gel to strips of nitrocellulose paper, followed by labeling with antibody probes.
Supplying a building or house, their rooms and corridors, with fresh air. The controlling of the environment thus may be in public or domestic sites and in medical or non-medical locales. (From Dorland, 28th ed)
A mixture of smoke and fog polluting the atmosphere. (Dorland, 27th ed)
A strain of albino rat developed at the Wistar Institute that has spread widely at other institutions. This has markedly diluted the original strain.
Divisions of the year according to some regularly recurrent phenomena usually astronomical or climatic. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
A strain of albino rat used widely for experimental purposes because of its calmness and ease of handling. It was developed by the Sprague-Dawley Animal Company.
An aspect of personal behavior or lifestyle, environmental exposure, or inborn or inherited characteristic, which, on the basis of epidemiologic evidence, is known to be associated with a health-related condition considered important to prevent.
Testing for the amount of biodegradable organic material in a water sample by measuring the quantity of oxygen consumed by biodegradation of those materials over a specific time period.
Compounds consisting of two or more fused ring structures.
Worthless, damaged, defective, superfluous or effluent material from industrial operations.
A form of bronchial disorder with three distinct components: airway hyper-responsiveness (RESPIRATORY HYPERSENSITIVITY), airway INFLAMMATION, and intermittent AIRWAY OBSTRUCTION. It is characterized by spasmodic contraction of airway smooth muscle, WHEEZING, and dyspnea (DYSPNEA, PAROXYSMAL).
AUTOMOBILES, trucks, buses, or similar engine-driven conveyances. (From Random House Unabridged Dictionary, 2d ed)
'Smoke' is a complex mixture of gases, fine particles, and volatile compounds, generally produced by combustion of organic substances, which can contain harmful chemicals known to have adverse health effects.
Studies designed to examine associations, commonly, hypothesized causal relations. They are usually concerned with identifying or measuring the effects of risk factors or exposures. The common types of analytic study are CASE-CONTROL STUDIES; COHORT STUDIES; and CROSS-SECTIONAL STUDIES.
Strains of mice in which certain GENES of their GENOMES have been disrupted, or "knocked-out". To produce knockouts, using RECOMBINANT DNA technology, the normal DNA sequence of the gene being studied is altered to prevent synthesis of a normal gene product. Cloned cells in which this DNA alteration is successful are then injected into mouse EMBRYOS to produce chimeric mice. The chimeric mice are then bred to yield a strain in which all the cells of the mouse contain the disrupted gene. Knockout mice are used as EXPERIMENTAL ANIMAL MODELS for diseases (DISEASE MODELS, ANIMAL) and to clarify the functions of the genes.
Inorganic and organic derivatives of sulfuric acid (H2SO4). The salts and esters of sulfuric acid are known as SULFATES and SULFURIC ACID ESTERS respectively.
Radioactive substances which act as pollutants. They include chemicals whose radiation is released via radioactive waste, nuclear accidents, fallout from nuclear explosions, and the like.
High temperature destruction of waste by burning with subsequent reduction to ashes or conversion to an inert mass.
Any combustible hydrocarbon deposit formed from the remains of prehistoric organisms. Examples are petroleum, coal, and natural gas.
Halogenated hydrocarbons refer to organic compounds containing carbon and hydrogen atoms, where one or more hydrogen atoms are replaced by halogens such as fluorine, chlorine, bromine, or iodine.
The maximum exposure to a biologically active physical or chemical agent that is allowed during an 8-hour period (a workday) in a population of workers, or during a 24-hour period in the general population, which does not appear to cause appreciable harm, whether immediate or delayed for any period, in the target population. (From Lewis Dictionary of Toxicology, 1st ed)
Any enterprise centered on the processing, assembly, production, or marketing of a line of products, services, commodities, or merchandise, in a particular field often named after its principal product. Examples include the automobile, fishing, music, publishing, insurance, and textile industries.
The presence in food of harmful, unpalatable, or otherwise objectionable foreign substances, e.g. chemicals, microorganisms or diluents, before, during, or after processing or storage.
Contamination of bodies of water (such as LAKES; RIVERS; SEAS; and GROUNDWATER.)
A cell line derived from cultured tumor cells.
A phase transition from liquid state to gas state, which is affected by Raoult's law. It can be accomplished by fractional distillation.
Diseases of the respiratory system in general or unspecified or for a specific respiratory disease not available.
All of the processes involved in increasing CELL NUMBER including CELL DIVISION.

Endocrine biomarkers of early fetal loss in cynomolgus macaques (Macaca fascicularis) following exposure to dioxin. (1/3283)

This study examines the endocrine alterations associated with early fetal loss (EFL) induced by an environmental toxin, TCDD (2,3,7, 8-tetrachlorodibenzo-p-dioxin), in the cynomolgus macaque, a well-documented reproductive/developmental model for humans. Females were administered single doses of 1, 2, and 4 microgram/kg TCDD (n = 4 per dose group) on gestational day (GD) 12. Urinary estrogen metabolites (estrone conjugates) were monitored to establish the day of ovulation, and serum hormones (estradiol, progesterone, chorionic gonadotropin, relaxin) were measured to assess ovarian and placental endocrine status before and after treatment. EFL occurred between GDs 22 and 32 in 10 of the 12 animals treated with TCDD. The primary endocrine alterations associated with TCDD treatment were significant decreases in serum estradiol and bioactive chorionic gonadotropin concentrations (p < 0.02). Less pronounced decreases in serum progesterone (p = 0.10) and relaxin (p < 0.08) also followed TCDD treatment. In contrast, immunoreactive chorionic gonadotropin concentrations were not reduced by TCDD exposure at any level, indicating that TCDD targets specific components of the chorionic gonadotropin synthesis machinery within the trophoblast to alter the functional capacity of the hormone. These data demonstrate the value of endocrine biomarkers in identifying a toxic exposure to primate pregnancy many days before direct signs of reproductive toxicity were apparent. The increased EFL that occurred after exposure to TCDD might reflect a toxic response initially mediated via endocrine imbalance, leading to placental insufficiency, compromised embryonic circulation, and subsequent EFL.  (+info)

Induction of hepatic cytochromes P450 in dogs exposed to a chronic low dose of polychlorinated biphenyls. (2/3283)

Induction of cytochrome P450 isoforms, specifically CYP1A1, and their catalytic activities are potential biomarkers of environmental contamination by polychlorinated biphenyls (PCBs). In this study, dogs were exposed to 25 ppm or 5 ppm Aroclor 1248 (PCB mixture) daily in their diet for 10 or 20 weeks, respectively. Relative to controls, hepatic microsomes from dogs dosed with PCBs had higher levels of CYP1A1 detected in immunoblots and higher levels of EROD activity, but low levels of induction for CYP2B and PROD activity. Concentrations of 96 PCB congeners in serum and liver were evaluated using capillary chromatography. Results showed that all dogs exposed to PCB mixtures had higher levels of PCB in serum and liver. Dogs preferentially sequestered highly chlorinated PCB congeners in liver relative to serum. With these experiments, we demonstrated that EROD activity was a potentially sensitive marker of PCB exposure at 5 and 25 ppm. Furthermore, CYP1A1 and EROD activity were maximally induced in dogs consuming dietary concentrations only 2.5 times the maximal permissible level for human food (FDA). The value of CYP1A1 induction as a biomarker of PCB exposure was tenuous because neither CYP1A1 levels nor EROD activity correlated with total PCB body burden. However, a small subset of congeners were identified in liver that may strongly influence EROD and PROD induction. Finally, two dogs in the 25 ppm dose group were fasted for 48 h. After 24 h of fasting, several new congeners appeared in the serum and remained in the serum for the remainder of the fast. The fast caused a 293% increase in PCB concentration in serum. This increase has strong implications regarding mobilization of toxic PCBs in wildlife during fasting (e.g., migration, hibernation).  (+info)

AhR, ARNT, and CYP1A1 mRNA quantitation in cultured human embryonic palates exposed to TCDD and comparison with mouse palate in vivo and in culture. (3/3283)

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is developmentally toxic in many species and induces cleft palate in the C57BL/6N mouse embryo. Palatogenesis in mouse and human embryos involves homologous processes at the morphological, cellular, and molecular levels. In organ culture, mouse and human palates respond similarly to TCDD. The present study quantitates the expression of AhR, ARNT, and CYP1A1 mRNA in human embryonic palates in organ culture. Palatal tissues were exposed to 1 x 10(-10), 1 x 10(-9), or 1 x 10(-8) M TCDD or control medium and sampled at 0, 2, 4, and 6 hours for quantitative RT-PCR using a synthetic RNA internal standard. Similar measurements of CYP1A1 gene expression were collected for mouse palates cultured in this model. In human palates, AhR expression correlated with ARNT and CYP1A1 mRNA expression. TCDD induction of CYP1A1 was time- and concentration-dependent. The expression of these genes presented a uniform and continuous distribution across the group of embryos, with no subset of either high or low expressors/responders. The ratio of AhR to ARNT was approximately 4:1. AhR mRNA increased during the culture period in both treated and control subjects; however, ARNT expression was relatively constant. TCDD did not alter either AhR or ARNT expression in a consistent dose- or time-related manner. Comparison of human and mouse data showed a high correlation across species for the induction of CYP1A1. Human embryos expressed approximately 350 times less AhR mRNA than the mouse, and in earlier studies it was shown that human palates required 200 times more TCDD to produce the same effects. When the morphological, cellular, and molecular responses to TCDD between mouse and human are compared, it seems highly unlikely that human embryos could be exposed to sufficient TCDD to achieve changes in palatal differentiation that would lead to cleft palate.  (+info)

RT-PCR quantification of AHR, ARNT, GR, and CYP1A1 mRNA in craniofacial tissues of embryonic mice exposed to 2,3,7,8-tetrachlorodibenzo-p-dioxin and hydrocortisone. (4/3283)

C57BL/6N mouse embryos exposed to hydrocortisone (HC) or 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) develop cleft palate. An interaction between these agents produces clefts at doses which alone are not teratogenic. The glucocorticoid receptor (GR) and dioxin receptor (AhR) mediated these responses and their gene expression was altered by TCDD and/or HC in palates examined on gestation day (GD) 14 by Northern blot analysis and in situ hybridization. The present study quantifies AhR, AhR nuclear translocator (ARNT), and GR mRNA at 4, 12, 24, and 48 h after exposure (time 0 = dose administration at 8 A.M. on gestation day 12) on GD12 to TCDD (24 micrograms/kg), HC (100 mg/kg) or HC (25 mg/kg) + TCDD (3 micrograms/kg). The induction of CYP1A1 mRNA was also quantified at 2, 4, 6, 12, 24, and 48 h for control and TCDD-exposed samples. Total RNA was prepared from midfacial tissue of 4-6 embryos/litter at each time and dose. An RNA internal standard (IS) for each gene was synthesized, which included the gene's primer sequences separated by a pUC19 plasmid sequence. Reverse transcription-polymerase chain reaction (RT-PCR) was performed on total RNA + IS using a range of 5-7 IS concentrations across a constant level of total RNA. PCR products were separated in gels (mRNA and IS-amplified sequences differed by 30-50 bases), ethidium bromide-stained, imaged (Hamamatsu Photonics Systems, Bridgewater, NJ), and quantified with NIH Image. CYP1A1 mRNA was significantly induced in the TCDD-exposed samples at all time points examined (p = 0.005 at 2 h and 0.001 after 2 h). During palatal shelf outgrowth on GD12, AhR mRNA levels increased significantly and this was not affected by treatment with TCDD or HC + TCDD. A significant increase in GR was detected at 24 h (p < 0.05) and this was unaffected by any of the exposures. Expression of ARNT increased at 12 h (p < 0.001); however, treatment with HC or HC + TCDD blocked this increase (p < 0.05). At 24 h, the TCDD-treated embryos had significantly lower ARNT mRNA compared with controls (p < 0.001). The relative overall expression level of the genes was AhR > ARNT > GR. Within individuals, expression of AhR and/or ARNT was highly correlated with GR level. In conclusion, CYP1A1 mRNA was expressed in developing craniofacial tissue and was highly induced by TCDD exposure. AhR, ARNT, and GR mRNA are upregulated in early palatogenesis, although not on the same schedule. The TCDD-induced decrease in ARNT at 24 h after dosing and the HC and HC + TCDD-induced delay in upregulation of ARNT may affect the dynamics of heterodimer formation between AhR and ARNT. The changes in ARNT mRNA level could also affect availability of this transcriptional regulator to interact with other potential partners, and these effects, separately or in combination, may be involved in disruption of normal embryonic development.  (+info)

Relationships between environmental organochlorine contaminant residues, plasma corticosterone concentrations, and intermediary metabolic enzyme activities in Great Lakes herring gull embryos. (5/3283)

Experiments were conducted to survey and detect differences in plasma corticosterone concentrations and intermediary metabolic enzyme activities in herring gull (Larus argentatus) embryos environmentally exposed to organochlorine contaminants in ovo. Unincubated fertile herring gull eggs were collected from an Atlantic coast control site and various Great Lakes sites in 1997 and artificially incubated in the laboratory. Liver and/or kidney tissues from approximately half of the late-stage embryos were analyzed for the activities of various intermediary metabolic enzymes known to be regulated, at least in part, by corticosteroids. Basal plasma corticosterone concentrations were determined for the remaining embryos. Yolk sacs were collected from each embryo and a subset was analyzed for organochlorine contaminants. Regression analysis of individual yolk sac organochlorine residue concentrations, or 2,3,7,8-tetrachlorodibenzo-p-dioxin equivalents (TEQs), with individual basal plasma corticosterone concentrations indicated statistically significant inverse relationships for polychlorinated dibenzo-p-dioxins/polychlorinated dibenzofurans (PCDDs/PCDFs), total polychlorinated biphenyls (PCBs), non-ortho PCBs, and TEQs. Similarly, inverse relationships were observed for the activities of two intermediary metabolic enzymes (phosphoenolpyruvate carboxykinase and malic enzyme) when regressed against PCDDs/PCDFs. Overall, these data suggest that current levels of organochlorine contamination may be affecting the hypothalamo-pituitary-adrenal axis and associated intermediary metabolic pathways in environmentally exposed herring gull embryos in the Great Lakes.  (+info)

Cancer mortality in agricultural regions of Minnesota. (6/3283)

Because of its unique geology, Minnesota can be divided into four agricultural regions: south-central region one (corn, soybeans); west-central region two (wheat, corn, soybeans); northwest region three (wheat, sugar beets, potatoes); and northeast region four (forested and urban in character). Cancer mortality (1980-1989) in agricultural regions one, two, and three was compared to region four. Using data compiled by the National Center for Health Statistics, cancer mortality was summarized by 5-year age groups, sex, race, and county. Age-standardized mortality rate ratios were calculated for white males and females for all ages combined, and for children aged 0-14. Increased mortality rate ratios and 95% confidence intervals (CIs) were observed for the following cancer sites: region one--lip (men), standardized rate ratio (SRR) = 2.70 (CI, 1.08-6.71); nasopharynx (women), SRR = 3.35 (CI, 1.20-9.31); region two--non-Hodgkin's lymphoma (women), SRR = 1.35 (CI, 1.09-1.66); and region three--prostate (men), SRR = 1.12 (CI, 1.00-1.26); thyroid (men), SRR = 2.95 (CI, 1.35-6.44); bone (men), SRR = 2.09 (CI, 1. 00-4.34); eye (women), SRR = 5.77 (CI, 1.90-17.50). Deficits of smoking-related cancers were noted. Excess cancers reported are consistent with earlier reports of agriculturally related cancers in the midwestern United States. However, reports on thyroid and bone cancer in association with agricultural pesticides are few in number. The highest use of fungicides occurs in region three. Ethylenebisdithiocarbamates, whose metabolite is a known cause of thyroid cancer in rats, are frequently applied. This report provides a rationale for evaluation of the carcinogenic potential of this suspect agent in humans.  (+info)

Quantitative analysis of constitutive and 2,3,7,8-tetrachlorodibenzo-p-dioxin-induced cytochrome P450 1B1 expression in human lymphocytes. (7/3283)

Exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD or dioxin) results in a broad spectrum of biological responses, including altered metabolism, disruption of normal hormone signaling pathways, reproductive and developmental effects, and cancer. Cytochrome P450 1B1 (CYP1B1) is a dioxin-inducible gene that is active in the formation of 4-hydroxyestradiol, a potentially genotoxic catechol estrogen. Therefore, the analysis of CYP1B1 in humans may be useful in establishing relationships between dioxin exposure and adverse health effects. In this study, we examined the expression of CYP1B1 in human peripheral blood lymphocytes of unexposed individuals using a quantitative reverse transcription-PCR method. Absolute CYP1B1 RNA levels varied more than 30-fold in uncultured mononuclear cells obtained from 10 individuals. In vitro treatment of mitogen-stimulated lymphocytes with TCDD for 1-5 days of culture resulted in a peak induction of CYP1B1 after 3 days. The induction of CYP1B1 RNA levels after 3 days of culture was dose-dependent, exhibited a maximum response above 10 nM TCDD, and varied greatly among different individuals. However, the half maximal dose required for this induction was similar between individuals and comparable to that observed in the MCF-7 and HepG2 human cell lines. These observations indicate that CYP1B1 exhibits variable constitutive expression and is inducible in vitro by TCDD in human lymphocytes and that the magnitude of induction varies within the population. These data define the suitability of CYP1B1 for use as a mechanistically based biomarker in ongoing molecular epidemiological studies of human populations exposed to dioxins and related chemicals that bind the aromatic hydrocarbon receptor.  (+info)

Environmental contaminants and body fat distribution. (8/3283)

The effect of body mass index (BMI) and waist:hip ratio (WHR) on plasma levels of organochlorines [i.e., 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (DDE)] was investigated in a sample of black and white women drawn from a population-based study in North Carolina. Organochlorine levels were determined in plasma samples from 99 women selected on the basis of race (black versus white) and quartile of the WHR (1st versus 4th). Of a panel of 20 organochlorine compounds tested, only DDE was detectable in most study subjects. Measurements of height, weight, and waist and hip circumferences were taken during an in-person interview. Information was elicited regarding dietary, residential, and breast-feeding histories. Results of multiple regression analyses indicate that black women had significantly higher plasma levels of DDE than white women. These levels were independent of BMI and WHR. BMI but not WHR was also found to be an independent predictor of DDE plasma level. These results suggest that black/white differences should be considered in studies that explore the relationship between environmental contaminants and various disease outcomes, such as breast cancer risk. In addition, BMI may affect circulating levels of contaminants and should also be considered a potentially important modifying factor for exposure to lipophilic substances.  (+info)

Environmental pollutants are defined as any substances or energy (such as noise, heat, or light) that are present in the environment and can cause harm or discomfort to humans or other living organisms, or damage the natural ecosystems. These pollutants can come from a variety of sources, including industrial processes, transportation, agriculture, and household activities. They can be in the form of gases, liquids, solids, or radioactive materials, and can contaminate air, water, and soil. Examples include heavy metals, pesticides, volatile organic compounds (VOCs), particulate matter, and greenhouse gases.

It is important to note that the impact of environmental pollutants on human health and the environment can be acute (short-term) or chronic (long-term) and it depends on the type, concentration, duration and frequency of exposure. Some common effects of environmental pollutants include respiratory problems, cancer, neurological disorders, reproductive issues, and developmental delays in children.

It is important to monitor, control and reduce the emissions of these pollutants through regulations, technology advancements, and sustainable practices to protect human health and the environment.

Air pollutants are substances or mixtures of substances present in the air that can have negative effects on human health, the environment, and climate. These pollutants can come from a variety of sources, including industrial processes, transportation, residential heating and cooking, agricultural activities, and natural events. Some common examples of air pollutants include particulate matter, nitrogen dioxide, sulfur dioxide, ozone, carbon monoxide, and volatile organic compounds (VOCs).

Air pollutants can cause a range of health effects, from respiratory irritation and coughing to more serious conditions such as bronchitis, asthma, and cancer. They can also contribute to climate change by reacting with other chemicals in the atmosphere to form harmful ground-level ozone and by directly absorbing or scattering sunlight, which can affect temperature and precipitation patterns.

Air quality standards and regulations have been established to limit the amount of air pollutants that can be released into the environment, and efforts are ongoing to reduce emissions and improve air quality worldwide.

Hexachlorobenzene (HCB) is not typically included in standard medical textbooks or resources as it's more of a environmental and industrial chemical. However, I can provide you with an definition from a toxicological perspective:

Hexachlorobenzene (C6Cl6) is an organic compound that consists of a benzene ring with six chlorine atoms attached to it. It is a persistent organic pollutant, which means it does not break down easily and can accumulate in the environment and living organisms. HCB has been used as a pesticide, fungicide, and chemical intermediate in various industrial processes. Exposure to this compound can lead to several health issues, including skin lesions, damage to the nervous system, and impaired immune function. It's also considered a possible human carcinogen by some agencies. Long-term environmental exposure to HCB is of particular concern due to its bioaccumulation in the food chain and potential adverse effects on human health and the environment.

Acrolein is an unsaturated aldehyde with the chemical formula CH2CHCHO. It is a colorless liquid that has a distinct unpleasant odor and is highly reactive. Acrolein is produced by the partial oxidation of certain organic compounds, such as glycerol and fatty acids, and it is also found in small amounts in some foods, such as coffee and bread.

Acrolein is a potent irritant to the eyes, nose, and throat, and exposure to high levels can cause coughing, wheezing, and shortness of breath. It has been shown to have toxic effects on the lungs, heart, and nervous system, and prolonged exposure has been linked to an increased risk of cancer.

In the medical field, acrolein is sometimes used as a laboratory reagent or as a preservative for biological specimens. However, due to its potential health hazards, it must be handled with care and appropriate safety precautions should be taken when working with this compound.

Polycyclic aromatic hydrocarbons (PAHs) are a group of organic compounds characterized by the presence of two or more fused benzene rings. They are called "polycyclic" because they contain multiple cyclic structures, and "aromatic" because these structures contain alternating double bonds that give them distinctive chemical properties and a characteristic smell.

PAHs can be produced from both natural and anthropogenic sources. Natural sources include wildfires, volcanic eruptions, and the decomposition of organic matter. Anthropogenic sources include the incomplete combustion of fossil fuels, such as coal, oil, and gasoline, as well as tobacco smoke, grilled foods, and certain industrial processes.

PAHs are known to be environmental pollutants and can have harmful effects on human health. They have been linked to an increased risk of cancer, particularly lung, skin, and bladder cancers, as well as reproductive and developmental toxicity. PAHs can also cause skin irritation, respiratory problems, and damage to the immune system.

PAHs are found in a variety of environmental media, including air, water, soil, and food. They can accumulate in the food chain, particularly in fatty tissues, and have been detected in a wide range of foods, including meat, fish, dairy products, and vegetables. Exposure to PAHs can occur through inhalation, ingestion, or skin contact.

It is important to limit exposure to PAHs by avoiding tobacco smoke, reducing consumption of grilled and smoked foods, using ventilation when cooking, and following safety guidelines when working with industrial processes that produce PAHs.

Chlorinated hydrocarbons are a group of organic compounds that contain carbon (C), hydrogen (H), and chlorine (Cl) atoms. These chemicals are formed by replacing one or more hydrogen atoms in a hydrocarbon molecule with chlorine atoms. The properties of chlorinated hydrocarbons can vary widely, depending on the number and arrangement of chlorine and hydrogen atoms in the molecule.

Chlorinated hydrocarbons have been widely used in various industrial applications, including as solvents, refrigerants, pesticides, and chemical intermediates. Some well-known examples of chlorinated hydrocarbons are:

1. Methylene chloride (dichloromethane) - a colorless liquid with a mild sweet odor, used as a solvent in various industrial applications, including the production of pharmaceuticals and photographic films.
2. Chloroform - a heavy, volatile, and sweet-smelling liquid, used as an anesthetic in the past but now mainly used in chemical synthesis.
3. Carbon tetrachloride - a colorless, heavy, and nonflammable liquid with a mildly sweet odor, once widely used as a solvent and fire extinguishing agent but now largely phased out due to its ozone-depleting properties.
4. Vinyl chloride - a flammable, colorless gas, used primarily in the production of polyvinyl chloride (PVC) plastic and other synthetic materials.
5. Polychlorinated biphenyls (PCBs) - a group of highly stable and persistent organic compounds that were widely used as coolants and insulating fluids in electrical equipment but are now banned due to their toxicity and environmental persistence.

Exposure to chlorinated hydrocarbons can occur through inhalation, skin contact, or ingestion, depending on the specific compound and its physical state. Some chlorinated hydrocarbons have been linked to various health effects, including liver and kidney damage, neurological disorders, reproductive issues, and cancer. Therefore, proper handling, use, and disposal of these chemicals are essential to minimize potential health risks.

Environmental exposure refers to the contact of an individual with any chemical, physical, or biological agent in the environment that can cause a harmful effect on health. These exposures can occur through various pathways such as inhalation, ingestion, or skin contact. Examples of environmental exposures include air pollution, water contamination, occupational chemicals, and allergens. The duration and level of exposure, as well as the susceptibility of the individual, can all contribute to the risk of developing an adverse health effect.

Polychlorinated biphenyls (PCBs) are a group of man-made organic chemicals consisting of 209 individual compounds, known as congeners. The congeners are formed by the combination of two benzene rings with varying numbers and positions of chlorine atoms.

PCBs were widely used in electrical equipment, such as transformers and capacitors, due to their non-flammability, chemical stability, and insulating properties. They were also used in other applications, including coolants and lubricants, plasticizers, pigments, and copy oils. Although PCBs were banned in many countries in the 1970s and 1980s due to their toxicity and environmental persistence, they still pose significant health and environmental concerns because of their continued presence in the environment and in products manufactured before the ban.

PCBs are known to have various adverse health effects on humans and animals, including cancer, immune system suppression, reproductive and developmental toxicity, and endocrine disruption. They can also cause neurological damage and learning and memory impairment in both human and animal populations. PCBs are highly persistent in the environment and can accumulate in the food chain, leading to higher concentrations in animals at the top of the food chain, including humans.

Tetrachlorodibenzodioxin (TCDD) is not a common medical term, but it is known in toxicology and environmental health. TCDD is the most toxic and studied compound among a group of chemicals known as dioxins.

Medical-related definition:

Tetrachlorodibenzodioxin (TCDD) is an unintended byproduct of various industrial processes, including waste incineration, chemical manufacturing, and pulp and paper bleaching. It is a highly persistent environmental pollutant that accumulates in the food chain, primarily in animal fat. Human exposure to TCDD mainly occurs through consumption of contaminated food, such as meat, dairy products, and fish. TCDD is a potent toxicant with various health effects, including immunotoxicity, reproductive and developmental toxicity, and carcinogenicity. The severity of these effects depends on the level and duration of exposure.

Aryl hydrocarbon receptors (AhRs) are a type of intracellular receptor that play a crucial role in the response to environmental contaminants and other xenobiotic compounds. They are primarily found in the cytoplasm of cells, where they bind to aromatic hydrocarbons, including polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs), which are common environmental pollutants.

Once activated by ligand binding, AhRs translocate to the nucleus, where they dimerize with the AhR nuclear translocator (ARNT) protein and bind to specific DNA sequences called xenobiotic response elements (XREs). This complex then regulates the expression of a variety of genes involved in xenobiotic metabolism, including those encoding cytochrome P450 enzymes.

In addition to their role in xenobiotic metabolism, AhRs have been implicated in various physiological processes, such as immune response, cell differentiation, and development. Dysregulation of AhR signaling has been associated with the pathogenesis of several diseases, including cancer, autoimmune disorders, and neurodevelopmental disorders.

Therefore, understanding the mechanisms of AhR activation and regulation is essential for developing strategies to prevent or treat environmental toxicant-induced diseases and other conditions linked to AhR dysfunction.

Chemical water pollutants refer to harmful chemicals or substances that contaminate bodies of water, making them unsafe for human use and harmful to aquatic life. These pollutants can come from various sources, including industrial and agricultural runoff, sewage and wastewater, oil spills, and improper disposal of hazardous materials.

Examples of chemical water pollutants include heavy metals (such as lead, mercury, and cadmium), pesticides and herbicides, volatile organic compounds (VOCs), polychlorinated biphenyls (PCBs), and petroleum products. These chemicals can have toxic effects on aquatic organisms, disrupt ecosystems, and pose risks to human health through exposure or consumption.

Regulations and standards are in place to monitor and limit the levels of chemical pollutants in water sources, with the aim of protecting public health and the environment.

Environmental pollution is the introduction or presence of harmful substances, energies, or objects in the environment that can cause adverse effects on living organisms and ecosystems. These pollutants can be in the form of chemical, physical, or biological agents that contaminate air, water, soil, or noise levels, exceeding safe limits established by environmental regulations.

Examples of environmental pollution include:

1. Air pollution: The presence of harmful substances such as particulate matter, sulfur dioxide, nitrogen oxides, and volatile organic compounds (VOCs) in the air that can cause respiratory and other health problems.
2. Water pollution: Contamination of water sources with chemicals, heavy metals, pathogens, or other pollutants that can harm aquatic life and make the water unsafe for human consumption or recreational use.
3. Soil pollution: The presence of harmful substances such as heavy metals, pesticides, and industrial waste in soil that can reduce soil fertility, contaminate crops, and pose a risk to human health.
4. Noise pollution: Excessive noise levels from transportation, industrial activities, or other sources that can cause stress, sleep disturbances, and hearing loss in humans and animals.
5. Light pollution: The excessive use of artificial light that can disrupt ecosystems, affect human circadian rhythms, and contribute to energy waste.

Environmental pollution is a significant global health issue that requires urgent attention and action from governments, industries, and individuals to reduce pollutant emissions, promote sustainable practices, and protect the environment for future generations.

Ozone (O3) is not a substance that is typically considered a component of health or medicine in the context of human body or physiology. It's actually a form of oxygen, but with three atoms instead of two, making it unstable and reactive. Ozone is naturally present in the Earth's atmosphere, where it forms a protective layer in the stratosphere that absorbs harmful ultraviolet (UV) radiation from the sun.

However, ozone can have both beneficial and detrimental effects on human health depending on its location and concentration. At ground level or in indoor environments, ozone is considered an air pollutant that can irritate the respiratory system and aggravate asthma symptoms when inhaled at high concentrations. It's important to note that ozone should not be confused with oxygen (O2), which is essential for human life and breathing.

Environmental biodegradation is the breakdown of materials, especially man-made substances such as plastics and industrial chemicals, by microorganisms such as bacteria and fungi in order to use them as a source of energy or nutrients. This process occurs naturally in the environment and helps to break down organic matter into simpler compounds that can be more easily absorbed and assimilated by living organisms.

Biodegradation in the environment is influenced by various factors, including the chemical composition of the substance being degraded, the environmental conditions (such as temperature, moisture, and pH), and the type and abundance of microorganisms present. Some substances are more easily biodegraded than others, and some may even be resistant to biodegradation altogether.

Biodegradation is an important process for maintaining the health and balance of ecosystems, as it helps to prevent the accumulation of harmful substances in the environment. However, some man-made substances, such as certain types of plastics and industrial chemicals, may persist in the environment for long periods of time due to their resistance to biodegradation, leading to negative impacts on wildlife and ecosystems.

In recent years, there has been increasing interest in developing biodegradable materials that can break down more easily in the environment as a way to reduce waste and minimize environmental harm. These efforts have led to the development of various biodegradable plastics, coatings, and other materials that are designed to degrade under specific environmental conditions.

Methylmercury compounds are organic forms of mercury, created when methyl groups (CH3) bind to a mercury ion (Hg+). These compounds can be highly toxic and bioaccumulate in living organisms, including humans. They are primarily formed in the environment through the action of bacteria on inorganic mercury, but can also be produced synthetically.

Methylmercury is particularly dangerous because it easily passes through biological membranes, allowing it to enter the brain and other tissues where it can cause significant damage. Exposure to high levels of methylmercury can lead to neurological problems, developmental issues in children, and even death. It's commonly found in contaminated fish and seafood, making these a significant source of human exposure.

Environmental monitoring is the systematic and ongoing surveillance, measurement, and assessment of environmental parameters, pollutants, or other stressors in order to evaluate potential impacts on human health, ecological systems, or compliance with regulatory standards. This process typically involves collecting and analyzing data from various sources, such as air, water, soil, and biota, and using this information to inform decisions related to public health, environmental protection, and resource management.

In medical terms, environmental monitoring may refer specifically to the assessment of environmental factors that can impact human health, such as air quality, water contamination, or exposure to hazardous substances. This type of monitoring is often conducted in occupational settings, where workers may be exposed to potential health hazards, as well as in community-based settings, where environmental factors may contribute to public health issues. The goal of environmental monitoring in a medical context is to identify and mitigate potential health risks associated with environmental exposures, and to promote healthy and safe environments for individuals and communities.

DNA adducts are chemical modifications or alterations that occur when DNA molecules become attached to or bound with certain harmful substances, such as toxic chemicals or carcinogens. These attachments can disrupt the normal structure and function of the DNA, potentially leading to mutations, genetic damage, and an increased risk of cancer and other diseases.

DNA adducts are formed when a reactive molecule from a chemical agent binds covalently to a base in the DNA molecule. This process can occur either spontaneously or as a result of exposure to environmental toxins, such as those found in tobacco smoke, certain industrial chemicals, and some medications.

The formation of DNA adducts is often used as a biomarker for exposure to harmful substances, as well as an indicator of potential health risks associated with that exposure. Researchers can measure the levels of specific DNA adducts in biological samples, such as blood or urine, to assess the extent and duration of exposure to certain chemicals or toxins.

It's important to note that not all DNA adducts are necessarily harmful, and some may even play a role in normal cellular processes. However, high levels of certain DNA adducts have been linked to an increased risk of cancer and other diseases, making them a focus of ongoing research and investigation.

Water pollutants refer to any substances or materials that contaminate water sources and make them unsafe or unsuitable for use. These pollutants can include a wide range of chemicals, microorganisms, and physical particles that can have harmful effects on human health, aquatic life, and the environment as a whole. Examples of water pollutants include heavy metals like lead and mercury, industrial chemicals such as polychlorinated biphenyls (PCBs) and dioxins, agricultural runoff containing pesticides and fertilizers, sewage and wastewater, oil spills, and microplastics. Exposure to water pollutants can cause a variety of health problems, ranging from minor irritations to serious illnesses or even death in extreme cases. Additionally, water pollution can have significant impacts on the environment, including harming or killing aquatic life, disrupting ecosystems, and reducing biodiversity.

Cytochrome P-450 CYP1A1 is an enzyme that is part of the cytochrome P450 family, which are a group of enzymes involved in the metabolism of drugs and other xenobiotics (foreign substances) in the body. Specifically, CYP1A1 is found primarily in the liver and lungs and plays a role in the metabolism of polycyclic aromatic hydrocarbons (PAHs), which are chemicals found in tobacco smoke and are produced by the burning of fossil fuels and other organic materials.

CYP1A1 also has the ability to activate certain procarcinogens, which are substances that can be converted into cancer-causing agents (carcinogens) within the body. Therefore, variations in the CYP1A1 gene may influence an individual's susceptibility to cancer and other diseases.

The term "P-450" refers to the fact that these enzymes absorb light at a wavelength of 450 nanometers when they are combined with carbon monoxide, giving them a characteristic pink color. The "CYP" stands for "cytochrome P," and the number and letter designations (e.g., 1A1) indicate the specific enzyme within the family.

Trialkyltin compounds are a category of organotin (oceanic) chemicals, characterized by the presence of three alkyl groups bonded to a tin atom. The general formula for these compounds is (CnH2n+1)3Sn, where n represents the number of carbon atoms in each alkyl group.

These compounds have been used in various industrial applications such as biocides, heat stabilizers, and PVC plasticizers. However, due to their high toxicity, environmental persistence, and potential bioaccumulation, their use has been restricted or banned in many countries.

Examples of trialkyltin compounds include tributyltin (TBT) and triphenyltin (TPT). TBT was widely used as an antifouling agent in marine paints to prevent the growth of barnacles, algae, and other organisms on ship hulls. However, due to its detrimental effects on marine life, particularly on shellfish and mollusks, its use has been largely phased out.

Trialkyltin compounds can have toxic effects on both aquatic and terrestrial organisms, including humans. They can cause neurological damage, impaired immune function, reproductive issues, and developmental abnormalities in various species.

Particulate Matter (PM) refers to the mixture of tiny particles and droplets in the air that are solid or liquid in nature. These particles vary in size, with some being visible to the naked eye while others can only be seen under a microscope. PM is classified based on its diameter:

* PM10 includes particles with a diameter of 10 micrometers or smaller. These particles are often found in dust, pollen, and smoke.
* PM2.5 includes particles with a diameter of 2.5 micrometers or smaller. These fine particles are produced from sources such as power plants, industrial processes, and vehicle emissions. They can also come from natural sources like wildfires.

Exposure to particulate matter has been linked to various health problems, including respiratory issues, cardiovascular disease, and premature death. The smaller the particle, the deeper it can penetrate into the lungs, making PM2.5 particularly harmful to human health.

Chrysenes are a group of polycyclic aromatic hydrocarbons (PAHs) that are found in the environment as a result of both natural processes and human activities such as combustion of fossil fuels, waste incineration, and cigarette smoke. They consist of four fused benzene rings and are highly stable, making them persistent in the environment. Chrysenes have been shown to have potential toxic, mutagenic, and carcinogenic effects on living organisms, including humans. They can accumulate in the food chain and pose a risk to human health through exposure via contaminated air, water, and food.

Pentachlorophenol is not primarily a medical term, but rather a chemical compound with some uses and applications in the medical field. Medically, it's important to understand what pentachlorophenol is due to its potential health implications.

Pentachlorophenol (PCP) is an organochlorine compound that has been widely used as a pesticide, wood preservative, and disinfectant. Its chemical formula is C6HCl5O. It is a white crystalline solid with a distinct, somewhat unpleasant odor. In the environment, pentachlorophenol can be found in soil, water, and air as well as in various organisms, including humans.

Pentachlorophenol has been associated with several potential health risks. It is classified as a probable human carcinogen by the International Agency for Research on Cancer (IARC) and as a possible human carcinogen by the United States Environmental Protection Agency (EPA). Exposure to pentachlorophenol can occur through inhalation, skin contact, or ingestion. Potential health effects include irritation of the skin, eyes, and respiratory tract; damage to the liver and kidneys; neurological issues; and reproductive problems.

In a medical context, pentachlorophenol might be relevant in cases where individuals have been exposed to this compound through occupational or environmental sources. Medical professionals may need to assess potential health risks, diagnose related health issues, and provide appropriate treatment.

'Vehicle Emissions' is not a term typically used in medical definitions. However, in a broader context, it refers to the gases and particles released into the atmosphere by vehicles such as cars, trucks, buses, and airplanes. The main pollutants found in vehicle emissions include carbon monoxide (CO), nitrogen oxides (NOx), particulate matter (PM), and volatile organic compounds (VOCs). Exposure to these pollutants can have negative health effects, including respiratory symptoms, cardiovascular disease, and cancer. Therefore, vehicle emissions are a significant public health concern.

Dioxins are a group of chemically-related compounds that are primarily formed as unintended byproducts of various industrial, commercial, and domestic processes. They include polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and certain polychlorinated biphenyls (PCBs). Dioxins are highly persistent environmental pollutants that accumulate in the food chain, particularly in animal fat. Exposure to dioxins can cause a variety of adverse health effects, including developmental and reproductive problems, immune system damage, hormonal disruption, and cancer. The most toxic form of dioxin is 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD).

I'm sorry for any confusion, but "soil pollutants" is not a term typically used in medical definitions. Soil pollution refers to the presence or accumulation of hazardous substances, chemicals, or other pollutants in soil that can have negative effects on plant life, human health, and the environment.

However, if you're asking about potential health effects of exposure to soil pollutants, it could include a variety of symptoms or diseases, depending on the specific pollutant. For example, exposure to lead-contaminated soil can lead to developmental delays in children, while exposure to certain pesticides or industrial chemicals can cause neurological problems, respiratory issues, and even cancer.

If you have more specific information about a particular substance or context, I may be able to provide a more precise answer.

Carcinogens are agents that can cause cancer. According to the National Institute of Environmental Health Sciences (NIEHS), environmental carcinogens refer to "cancer-causing agents that people encounter in their daily lives, including substances or exposures in air, water, food, and in the workplace." These carcinogens can increase the risk of cancer by damaging DNA or interfering with cellular processes that control growth.

Examples of environmental carcinogens include:

* Air pollution: Certain pollutants in the air, such as diesel exhaust particles and secondhand smoke, have been linked to an increased risk of lung cancer.
* Radon: A naturally occurring radioactive gas that can accumulate in homes and other buildings, radon is the second leading cause of lung cancer in the United States.
* UV radiation: Exposure to ultraviolet (UV) radiation from the sun or tanning beds can lead to skin cancer.
* Certain chemicals: Some chemicals found in the workplace or in consumer products, such as asbestos, benzene, and vinyl chloride, have been linked to an increased risk of cancer.
* Infectious agents: Certain viruses, bacteria, and parasites can increase the risk of cancer. For example, human papillomavirus (HPV) is a major cause of cervical cancer, and hepatitis B and C viruses are leading causes of liver cancer.

It's important to note that exposure to environmental carcinogens does not guarantee that a person will develop cancer. The risk depends on many factors, including the level and duration of exposure, as well as individual susceptibility. However, reducing exposure to these agents can help reduce the overall risk of cancer.

Cadmium is a toxic heavy metal that is a byproduct of the mining and smelting of zinc, lead, and copper. It has no taste or smell and can be found in small amounts in air, water, and soil. Cadmium can also be found in some foods, such as kidneys, liver, and shellfish.

Exposure to cadmium can cause a range of health effects, including kidney damage, lung disease, fragile bones, and cancer. Cadmium is classified as a known human carcinogen by the International Agency for Research on Cancer (IARC) and the National Toxicology Program (NTP).

Occupational exposure to cadmium can occur in industries that produce or use cadmium, such as battery manufacturing, metal plating, and pigment production. Workers in these industries may be exposed to cadmium through inhalation of cadmium-containing dusts or fumes, or through skin contact with cadmium-containing materials.

The general population can also be exposed to cadmium through the environment, such as by eating contaminated food or breathing secondhand smoke. Smoking is a major source of cadmium exposure for smokers and those exposed to secondhand smoke.

Prevention measures include reducing occupational exposure to cadmium, controlling emissions from industrial sources, and reducing the use of cadmium in consumer products. Regular monitoring of air, water, and soil for cadmium levels can also help identify potential sources of exposure and prevent health effects.

Halogenated diphenyl ethers are a group of chemical compounds that consist of two phenyl rings (aromatic hydrocarbon rings) linked by an ether group, with one or more halogens attached to the rings. The halogens can include chlorine, bromine, fluorine, or iodine atoms.

One of the most well-known halogenated diphenyl ethers is polychlorinated biphenyl (PCB), which was widely used in electrical equipment and industrial applications until it was banned due to its toxicity and environmental persistence. PCBs are known to have various adverse health effects, including cancer, reproductive disorders, and endocrine disruption.

Other halogenated diphenyl ethers, such as polybrominated diphenyl ethers (PBDEs), have also been used as flame retardants in consumer products, but their use has been restricted or phased out due to health and environmental concerns. Exposure to these compounds can occur through contaminated food, air, dust, and water, and may lead to similar health effects as PCB exposure.

Nitrogen dioxide (NO2) is a gaseous air pollutant and respiratory irritant. It is a reddish-brown toxic gas with a pungent, choking odor. NO2 is a major component of smog and is produced from the combustion of fossil fuels in vehicles, power plants, and industrial processes.

Exposure to nitrogen dioxide can cause respiratory symptoms such as coughing, wheezing, and difficulty breathing, especially in people with asthma or other respiratory conditions. Long-term exposure has been linked to the development of chronic lung diseases, including bronchitis and emphysema. NO2 also contributes to the formation of fine particulate matter (PM2.5), which can penetrate deep into the lungs and cause additional health problems.

I'm sorry for any confusion, but "Pyrenes" is not a medical term. It is a term used in chemistry and materials science, referring to a type of aromatic hydrocarbon molecule that consists of two benzene rings fused together. If you have a different term or concept in mind, please provide it so I can give you an accurate definition or information.

Air pollution is defined as the contamination of air due to the presence of substances or harmful elements that exceed the acceptable limits. These pollutants can be in the form of solid particles, liquid droplets, gases, or a combination of these. They can be released from various sources, including industrial processes, vehicle emissions, burning of fossil fuels, and natural events like volcanic eruptions.

Exposure to air pollution can have significant impacts on human health, contributing to respiratory diseases, cardiovascular issues, and even premature death. It can also harm the environment, damaging crops, forests, and wildlife populations. Stringent regulations and measures are necessary to control and reduce air pollution levels, thereby protecting public health and the environment.

Sulfur dioxide (SO2) is not a medical term per se, but it's an important chemical compound with implications in human health and medicine. Here's a brief definition:

Sulfur dioxide (SO2) is a colorless gas with a sharp, pungent odor. It is primarily released into the atmosphere as a result of human activities such as the burning of fossil fuels (like coal and oil) and the smelting of metals. SO2 is also produced naturally during volcanic eruptions and some biological processes.

In medical terms, exposure to high levels of sulfur dioxide can have adverse health effects, particularly for people with respiratory conditions like asthma or chronic obstructive pulmonary disease (COPD). SO2 can irritate the eyes, nose, throat, and lungs, causing coughing, wheezing, shortness of breath, and a tight feeling in the chest. Prolonged exposure to elevated levels of SO2 may exacerbate existing respiratory issues and lead to decreased lung function.

Regulations are in place to limit sulfur dioxide emissions from industrial sources to protect public health and reduce air pollution.

Flame retardants are chemical compounds that are added to materials, such as textiles, plastics, and foam furnishings, to reduce their flammability and prevent or slow down the spread of fire. They work by releasing non-flammable gases when exposed to heat, which helps to suppress the flames and prevent ignition. Flame retardants can be applied during the manufacturing process or added as a coating or treatment to existing materials. While flame retardants have been shown to save lives and property by preventing fires or reducing their severity, some types of flame retardants have been linked to health concerns, including endocrine disruption, neurodevelopmental toxicity, and cancer. Therefore, it is important to use flame retardants that are safe for human health and the environment.

Benzene is a colorless, flammable liquid with a sweet odor. It has the molecular formula C6H6 and is composed of six carbon atoms arranged in a ring, bonded to six hydrogen atoms. Benzene is an important industrial solvent and is used as a starting material in the production of various chemicals, including plastics, rubber, resins, and dyes. It is also a natural component of crude oil and gasoline.

In terms of medical relevance, benzene is classified as a human carcinogen by the International Agency for Research on Cancer (IARC) and the Environmental Protection Agency (EPA). Long-term exposure to high levels of benzene can cause various health effects, including anemia, leukemia, and other blood disorders. Occupational exposure to benzene is regulated by the Occupational Safety and Health Administration (OSHA) to protect workers from potential health hazards.

It's important to note that while benzene has legitimate uses in industry, it should be handled with care due to its known health risks. Exposure to benzene can occur through inhalation, skin contact, or accidental ingestion, so appropriate safety measures must be taken when handling this chemical.

Trichloroethylene (TCE) is a volatile, colorless liquid with a chloroform-like odor. In the medical field, it is primarily used as a surgical anesthetic and an analgesic. However, its use in medicine has significantly decreased due to the availability of safer alternatives.

In a broader context, TCE is widely used in various industries as a solvent for cleaning metal parts, degreasing fabrics and other materials, and as a refrigerant. It's also present in some consumer products like paint removers, adhesives, and typewriter correction fluids.

Prolonged or repeated exposure to TCE can lead to various health issues, including neurological problems, liver and kidney damage, and an increased risk of certain cancers. Therefore, its use is regulated by environmental and occupational safety agencies worldwide.

"Maternal exposure" is a medical term that refers to the contact or interaction of a pregnant woman with various environmental factors, such as chemicals, radiation, infectious agents, or physical environments, which could potentially have an impact on the developing fetus. This exposure can occur through different routes, including inhalation, ingestion, dermal contact, or even transplacentally. The effects of maternal exposure on the fetus can vary widely depending on the type, duration, and intensity of the exposure, as well as the stage of pregnancy at which it occurs. It is important to monitor and minimize maternal exposure to potentially harmful substances or environments during pregnancy to ensure the best possible outcomes for both the mother and developing fetus.

Aroclors are a series of polychlorinated biphenyl (PCB) mixtures that were manufactured by the Monsanto Company. They were widely used as cooling and insulating fluids in electrical equipment, such as transformers and capacitors, due to their non-flammability, chemical stability, and electrical insulating properties.

The term "Aroclor" is followed by a four-digit number that indicates the specific mixture and its average degree of chlorination. For example, Aroclor 1242 contains approximately 42% chlorine by weight, while Aroclor 1260 contains approximately 60% chlorine by weight.

Because of their persistence in the environment and potential toxicity to humans and wildlife, the production and use of PCBs, including Aroclors, were banned in the United States in 1979 under the Toxic Substances Control Act. However, due to their widespread historical use, PCBs continue to be a significant environmental pollutant and can still be found in many older electrical equipment, building materials, and soil and water samples.

Cadmium chloride is an inorganic compound with the chemical formula CdCl2. It is a white crystalline solid that is highly soluble in water and has a bitter, metallic taste. Cadmium chloride is a toxic compound that can cause serious health effects, including kidney damage, respiratory problems, and bone degeneration. It is classified as a hazardous substance and should be handled with care.

Cadmium chloride is used in various industrial applications, such as electroplating, soldering, and as a stabilizer in plastics. It is also used in some research settings as a reagent in chemical reactions.

It's important to note that exposure to cadmium chloride should be avoided, and appropriate safety measures should be taken when handling this compound. This includes wearing protective clothing, such as gloves and lab coats, and working in a well-ventilated area or under a fume hood. In case of accidental ingestion or inhalation, seek medical attention immediately.

Plasticizers are substances added to polymers or plastics to increase their flexibility, workability, and durability. They achieve this by reducing the intermolecular forces between polymer chains, thereby lowering the glass transition temperature (Tg) of the material. This allows the plastic to remain flexible even at lower temperatures. Common plasticizers include phthalates, adipates, and epoxy compounds. It is important to note that some plasticizers can have potential health concerns, and their use may be regulated in certain applications.

Aromatic hydrocarbons, also known as aromatic compounds or arenes, are a class of organic compounds characterized by a planar ring structure with delocalized electrons that give them unique chemical properties. The term "aromatic" was originally used to describe their distinctive odors, but it now refers to their characteristic molecular structure and stability.

Aromatic hydrocarbons contain one or more benzene rings, which are cyclic structures consisting of six carbon atoms arranged in a planar hexagonal shape. Each carbon atom in the benzene ring is bonded to two other carbon atoms and one hydrogen atom, forming alternating double and single bonds between the carbon atoms. However, the delocalized electrons in the benzene ring are evenly distributed around the ring, leading to a unique electronic structure that imparts stability and distinctive chemical properties to aromatic hydrocarbons.

Examples of aromatic hydrocarbons include benzene, toluene, xylene, and naphthalene. These compounds have important uses in industry, but they can also pose health risks if not handled properly. Exposure to high levels of aromatic hydrocarbons has been linked to various health effects, including cancer, neurological damage, and respiratory problems.

Environmental health is a branch of public health that focuses on the study of how environmental factors, including physical, chemical, and biological factors, impact human health and disease. It involves the assessment, control, and prevention of environmental hazards in order to protect and promote human health and well-being.

Environmental health encompasses a wide range of issues, such as air and water quality, food safety, waste management, housing conditions, occupational health and safety, radiation protection, and climate change. It also involves the promotion of healthy behaviors and the development of policies and regulations to protect public health from environmental hazards.

The goal of environmental health is to create safe and healthy environments that support human health and well-being, prevent disease and injury, and promote sustainable communities. This requires a multidisciplinary approach that involves collaboration between various stakeholders, including policymakers, researchers, healthcare providers, community organizations, and the public.

Heavy metals are a group of elements with a specific gravity at least five times greater than that of water. They include metals such as mercury (Hg), cadmium (Cd), arsenic (As), chromium (Cr), thallium (Tl), and lead (Pb). These metals are considered toxic when they accumulate in the body beyond certain levels, interfering with various biological processes and causing damage to cells, tissues, and organs.

Heavy metal exposure can occur through various sources, including occupational exposure, contaminated food, water, or air, and improper disposal of electronic waste. Chronic exposure to heavy metals has been linked to several health issues, such as neurological disorders, kidney damage, developmental problems, and cancer. Monitoring and controlling exposure to these elements is essential for maintaining good health and preventing potential adverse effects.

Xenobiotics are substances that are foreign to a living organism and usually originate outside of the body. This term is often used in the context of pharmacology and toxicology to refer to drugs, chemicals, or other agents that are not naturally produced by or expected to be found within the body.

When xenobiotics enter the body, they undergo a series of biotransformation processes, which involve metabolic reactions that convert them into forms that can be more easily excreted from the body. These processes are primarily carried out by enzymes in the liver and other organs.

It's worth noting that some xenobiotics can have beneficial effects on the body when used as medications or therapeutic agents, while others can be harmful or toxic. Therefore, understanding how the body metabolizes and eliminates xenobiotics is important for developing safe and effective drugs, as well as for assessing the potential health risks associated with exposure to environmental chemicals and pollutants.

Pesticides are substances or mixtures of substances intended for preventing, destroying, or repelling pests. Pests can be insects, rodents, fungi, weeds, or other organisms that can cause damage to crops, animals, or humans and their living conditions. The term "pesticide" includes all of the following: insecticides, herbicides, fungicides, rodenticides, bactericides, and various other substances used to control pests.

It is important to note that while pesticides are designed to be toxic to the target pests, they can also pose risks to non-target organisms, including humans, if not used properly. Therefore, it is essential to follow all label instructions and safety precautions when handling and applying pesticides.

Endocrine disruptors are defined as exogenous (external) substances or mixtures that interfere with the way hormones work in the body, leading to negative health effects. They can mimic, block, or alter the normal synthesis, secretion, transport, binding, action, or elimination of natural hormones in the body responsible for maintaining homeostasis, reproduction, development, and/or behavior.

Endocrine disruptors can be found in various sources, including industrial chemicals, pesticides, pharmaceuticals, and personal care products. They have been linked to a range of health problems, such as cancer, reproductive issues, developmental disorders, neurological impairments, and immune system dysfunction.

Examples of endocrine disruptors include bisphenol A (BPA), phthalates, dioxins, polychlorinated biphenyls (PCBs), perfluoroalkyl substances (PFAS), and certain pesticides like dichlorodiphenyltrichloroethane (DDT) and vinclozolin.

It is important to note that endocrine disruptors can have effects at very low doses, and their impact may depend on the timing of exposure, particularly during critical windows of development such as fetal growth and early childhood.

DDT (dichlorodiphenyltrichloroethane) is a synthetic insecticide that was widely used in the mid-20th century to control agricultural pests and vector-borne diseases such as malaria. It belongs to a class of chemicals called organochlorines, which are known for their persistence in the environment and potential for bioaccumulation in the food chain.

DDT was first synthesized in 1874, but its insecticidal properties were not discovered until 1939. Its use as an insecticide became widespread during World War II, when it was used to control typhus and malaria-carrying lice and mosquitoes among troops. After the war, DDT was widely adopted for agricultural and public health purposes.

However, concerns about the environmental and human health effects of DDT led to its ban or severe restriction in many countries starting in the 1970s. The United States banned the use of DDT for most purposes in 1972, and the Stockholm Convention on Persistent Organic Pollutants (POPs) prohibited its production and use globally in 2004, except in cases where there is a risk of vector-borne diseases.

DDT has been linked to several health problems, including reproductive effects, developmental toxicity, neurotoxicity, and endocrine disruption. It is also highly persistent in the environment, with a half-life of up to 15 years in soil and up to 30 years in water. This means that DDT can accumulate in the food chain, posing risks to wildlife and humans who consume contaminated food or water.

In summary, DDT is a synthetic insecticide that was widely used in the mid-20th century but has been banned or restricted in many countries due to its environmental and health effects. It belongs to a class of chemicals called organochlorines, which are known for their persistence in the environment and potential for bioaccumulation in the food chain. DDT has been linked to several health problems, including reproductive effects, developmental toxicity, neurotoxicity, and endocrine disruption.

Carcinogens are agents (substances or mixtures of substances) that can cause cancer. They may be naturally occurring or man-made. Carcinogens can increase the risk of cancer by altering cellular DNA, disrupting cellular function, or promoting cell growth. Examples of carcinogens include certain chemicals found in tobacco smoke, asbestos, UV radiation from the sun, and some viruses.

It's important to note that not all exposures to carcinogens will result in cancer, and the risk typically depends on factors such as the level and duration of exposure, individual genetic susceptibility, and lifestyle choices. The International Agency for Research on Cancer (IARC) classifies carcinogens into different groups based on the strength of evidence linking them to cancer:

Group 1: Carcinogenic to humans
Group 2A: Probably carcinogenic to humans
Group 2B: Possibly carcinogenic to humans
Group 3: Not classifiable as to its carcinogenicity to humans
Group 4: Probably not carcinogenic to humans

This information is based on medical research and may be subject to change as new studies become available. Always consult a healthcare professional for medical advice.

Polybrominated Biphenyls (PBBs) are a group of chemically related compounds that were widely used as flame retardants in various consumer products, such as electronics, appliances, and textiles. Structurally, they consist of two benzene rings with bromine atoms attached to them in different positions. PBBs have been banned or restricted in many countries due to their environmental persistence, bioaccumulation, and potential adverse health effects.

Here is a medical definition for Polybrominated Biphenyls (PBBs):

A class of brominated aromatic compounds that were historically used as flame retardants in various industrial and consumer applications. Due to their environmental persistence, bioaccumulation potential, and toxicity concerns, their production and use have been significantly restricted or banned in many countries. Exposure to PBBs can occur through ingestion, inhalation, or dermal contact and may lead to a variety of health issues, including endocrine disruption, reproductive and developmental effects, neurodevelopmental toxicity, and immune system alterations. Long-term exposure to high levels of PBBs can result in skin irritation, liver damage, and thyroid hormone disruption.

Inhalation exposure is a term used in occupational and environmental health to describe the situation where an individual breathes in substances present in the air, which could be gases, vapors, fumes, mist, or particulate matter. These substances can originate from various sources, such as industrial processes, chemical reactions, or natural phenomena.

The extent of inhalation exposure is determined by several factors, including:

1. Concentration of the substance in the air
2. Duration of exposure
3. Frequency of exposure
4. The individual's breathing rate
5. The efficiency of the individual's respiratory protection, if any

Inhalation exposure can lead to adverse health effects, depending on the toxicity and concentration of the inhaled substances. Short-term or acute health effects may include irritation of the eyes, nose, throat, or lungs, while long-term or chronic exposure can result in more severe health issues, such as respiratory diseases, neurological disorders, or cancer.

It is essential to monitor and control inhalation exposures in occupational settings to protect workers' health and ensure compliance with regulatory standards. Various methods are employed for exposure assessment, including personal air sampling, area monitoring, and biological monitoring. Based on the results of these assessments, appropriate control measures can be implemented to reduce or eliminate the risks associated with inhalation exposure.

Biotransformation is the metabolic modification of a chemical compound, typically a xenobiotic (a foreign chemical substance found within an living organism), by a biological system. This process often involves enzymatic conversion of the parent compound to one or more metabolites, which may be more or less active, toxic, or mutagenic than the original substance.

In the context of pharmacology and toxicology, biotransformation is an important aspect of drug metabolism and elimination from the body. The liver is the primary site of biotransformation, but other organs such as the kidneys, lungs, and gastrointestinal tract can also play a role.

Biotransformation can occur in two phases: phase I reactions involve functionalization of the parent compound through oxidation, reduction, or hydrolysis, while phase II reactions involve conjugation of the metabolite with endogenous molecules such as glucuronic acid, sulfate, or acetate to increase its water solubility and facilitate excretion.

Mutagens are physical or chemical agents that can cause permanent changes in the structure of genetic material, including DNA and chromosomes, leading to mutations. These mutations can be passed down to future generations and may increase the risk of cancer and other diseases. Examples of mutagens include ultraviolet (UV) radiation, tobacco smoke, and certain chemicals found in industrial settings. It is important to note that not all mutations are harmful, but some can have negative effects on health and development.

Mutagenicity tests are a type of laboratory assays used to identify agents that can cause genetic mutations. These tests detect changes in the DNA of organisms, such as bacteria, yeast, or mammalian cells, after exposure to potential mutagens. The most commonly used mutagenicity test is the Ames test, which uses a strain of Salmonella bacteria that is sensitive to mutagens. If a chemical causes an increase in the number of revertants (reversion to the wild type) in the bacterial population, it is considered to be a mutagen. Other tests include the mouse lymphoma assay and the chromosomal aberration test. These tests are used to evaluate the potential genotoxicity of chemicals and are an important part of the safety evaluation process for new drugs, chemicals, and other substances.

Deoxyguanosine is a chemical compound that is a component of DNA (deoxyribonucleic acid), one of the nucleic acids. It is a nucleoside, which is a molecule consisting of a sugar (in this case, deoxyribose) and a nitrogenous base (in this case, guanine). Deoxyguanosine plays a crucial role in the structure and function of DNA, as it pairs with deoxycytidine through hydrogen bonding to form a rung in the DNA double helix. It is involved in the storage and transmission of genetic information.

Maternal-fetal exchange, also known as maternal-fetal transport or placental transfer, refers to the physiological process by which various substances are exchanged between the mother and fetus through the placenta. This exchange includes the transfer of oxygen and nutrients from the mother's bloodstream to the fetal bloodstream, as well as the removal of waste products and carbon dioxide from the fetal bloodstream to the mother's bloodstream.

The process occurs via passive diffusion, facilitated diffusion, and active transport mechanisms across the placental barrier, which is composed of fetal capillary endothelial cells, the extracellular matrix, and the syncytiotrophoblast layer of the placenta. The maternal-fetal exchange is crucial for the growth, development, and survival of the fetus throughout pregnancy.

Petroleum is not a medical term, but it is a term used in the field of geology and petrochemicals. It refers to a naturally occurring liquid found in rock formations, which is composed of a complex mixture of hydrocarbons, organic compounds consisting primarily of carbon and hydrogen.

Petroleum is not typically associated with medical definitions; however, it's worth noting that petroleum and its derivatives are widely used in the production of various medical supplies, equipment, and pharmaceuticals. Some examples include plastic syringes, disposable gloves, catheters, lubricants for medical devices, and many active ingredients in medications.

In a broader sense, environmental or occupational exposure to petroleum and its byproducts could lead to health issues, but these are not typically covered under medical definitions of petroleum itself.

In the context of medicine, "lead" most commonly refers to lead exposure or lead poisoning. Lead is a heavy metal that can be harmful to the human body, even at low levels. It can enter the body through contaminated air, water, food, or soil, and it can also be absorbed through the skin.

Lead poisoning occurs when lead builds up in the body over time, causing damage to the brain, nervous system, red blood cells, and kidneys. Symptoms of lead poisoning may include abdominal pain, constipation, fatigue, headache, irritability, memory problems, and in severe cases, seizures, coma, or even death.

Lead exposure is particularly dangerous for children, as their developing bodies are more sensitive to the harmful effects of lead. Even low levels of lead exposure can cause learning disabilities, behavioral problems, and developmental delays in children. Therefore, it's important to minimize lead exposure and seek medical attention if lead poisoning is suspected.

Phenols, also known as phenolic acids or phenol derivatives, are a class of chemical compounds consisting of a hydroxyl group (-OH) attached to an aromatic hydrocarbon ring. In the context of medicine and biology, phenols are often referred to as a type of antioxidant that can be found in various foods and plants.

Phenols have the ability to neutralize free radicals, which are unstable molecules that can cause damage to cells and contribute to the development of chronic diseases such as cancer, heart disease, and neurodegenerative disorders. Some common examples of phenolic compounds include gallic acid, caffeic acid, ferulic acid, and ellagic acid, among many others.

Phenols can also have various pharmacological activities, including anti-inflammatory, antimicrobial, and analgesic effects. However, some phenolic compounds can also be toxic or irritating to the body in high concentrations, so their use as therapeutic agents must be carefully monitored and controlled.

Phthalic acids are organic compounds with the formula C6H4(COOH)2. They are white crystalline solids that are slightly soluble in water and more soluble in organic solvents. Phthalic acids are carboxylic acids, meaning they contain a functional group consisting of a carbon atom double-bonded to an oxygen atom and single-bonded to a hydroxyl group (-OH).

Phthalic acids are important intermediates in the chemical industry and are used to produce a wide range of products, including plastics, resins, and personal care products. They are also used as solvents and as starting materials for the synthesis of other chemicals.

Phthalic acids can be harmful if swallowed, inhaled, or absorbed through the skin. They can cause irritation to the eyes, skin, and respiratory tract, and prolonged exposure can lead to more serious health effects. Some phthalates, which are compounds that contain phthalic acid, have been linked to reproductive and developmental problems in animals and are considered to be endocrine disruptors. As a result, the use of certain phthalates has been restricted in some countries.

Toxicity tests, also known as toxicity assays, are a set of procedures used to determine the harmful effects of various substances on living organisms, typically on cells, tissues, or whole animals. These tests measure the degree to which a substance can cause damage, inhibit normal functioning, or lead to death in exposed organisms.

Toxicity tests can be conducted in vitro (in a test tube or petri dish) using cell cultures or in vivo (in living organisms) using animals such as rats, mice, or rabbits. The results of these tests help researchers and regulators assess the potential risks associated with exposure to various chemicals, drugs, or environmental pollutants.

There are several types of toxicity tests, including:

1. Acute toxicity tests: These tests measure the immediate effects of a single exposure to a substance over a short period (usually 24 hours or less).
2. Chronic toxicity tests: These tests evaluate the long-term effects of repeated exposures to a substance over an extended period (weeks, months, or even years).
3. Genotoxicity tests: These tests determine whether a substance can damage DNA or cause mutations in genetic material.
4. Developmental and reproductive toxicity tests: These tests assess the impact of a substance on fertility, embryonic development, and offspring health.
5. Carcinogenicity tests: These tests evaluate the potential of a substance to cause cancer.
6. Ecotoxicity tests: These tests determine the effects of a substance on entire ecosystems, including plants, animals, and microorganisms.

Toxicity tests play a crucial role in protecting public health by helping to identify potentially harmful substances and establish safe exposure levels. They also contribute to the development of new drugs, chemicals, and consumer products by providing critical data for risk assessment and safety evaluation.

A micronucleus test is a type of genetic toxicology assay used to detect the presence of micronuclei in cells, which are small chromosomal fragments or whole chromosomes that have been missegregated during cell division. The test measures the frequency of micronuclei in cells exposed to a potential genotoxic agent, such as a chemical or radiation, and compares it to the frequency in untreated control cells.

The assay is typically performed on cultured mammalian cells, such as human lymphocytes or Chinese hamster ovary (CHO) cells, and involves exposing the cells to the test agent for a specific period of time, followed by staining and examination of the cells under a microscope. The micronuclei are identified based on their size, shape, and staining characteristics, and the frequency of micronucleated cells is calculated as a measure of genotoxic potential.

Micronucleus tests are widely used in regulatory toxicology to assess the genetic safety of chemicals, drugs, and other substances, and can provide valuable information on potential risks to human health. The test is also used in basic research to study the mechanisms of genotoxicity and chromosomal instability.

The Cytochrome P-450 (CYP450) enzyme system is a group of enzymes found primarily in the liver, but also in other organs such as the intestines, lungs, and skin. These enzymes play a crucial role in the metabolism and biotransformation of various substances, including drugs, environmental toxins, and endogenous compounds like hormones and fatty acids.

The name "Cytochrome P-450" refers to the unique property of these enzymes to bind to carbon monoxide (CO) and form a complex that absorbs light at a wavelength of 450 nm, which can be detected spectrophotometrically.

The CYP450 enzyme system is involved in Phase I metabolism of xenobiotics, where it catalyzes oxidation reactions such as hydroxylation, dealkylation, and epoxidation. These reactions introduce functional groups into the substrate molecule, which can then undergo further modifications by other enzymes during Phase II metabolism.

There are several families and subfamilies of CYP450 enzymes, each with distinct substrate specificities and functions. Some of the most important CYP450 enzymes include:

1. CYP3A4: This is the most abundant CYP450 enzyme in the human liver and is involved in the metabolism of approximately 50% of all drugs. It also metabolizes various endogenous compounds like steroids, bile acids, and vitamin D.
2. CYP2D6: This enzyme is responsible for the metabolism of many psychotropic drugs, including antidepressants, antipsychotics, and beta-blockers. It also metabolizes some endogenous compounds like dopamine and serotonin.
3. CYP2C9: This enzyme plays a significant role in the metabolism of warfarin, phenytoin, and nonsteroidal anti-inflammatory drugs (NSAIDs).
4. CYP2C19: This enzyme is involved in the metabolism of proton pump inhibitors, antidepressants, and clopidogrel.
5. CYP2E1: This enzyme metabolizes various xenobiotics like alcohol, acetaminophen, and carbon tetrachloride, as well as some endogenous compounds like fatty acids and prostaglandins.

Genetic polymorphisms in CYP450 enzymes can significantly affect drug metabolism and response, leading to interindividual variability in drug efficacy and toxicity. Understanding the role of CYP450 enzymes in drug metabolism is crucial for optimizing pharmacotherapy and minimizing adverse effects.

In the context of medicine, Mercury does not have a specific medical definition. However, it may refer to:

1. A heavy, silvery-white metal that is liquid at room temperature. It has been used in various medical and dental applications, such as therapeutic remedies (now largely discontinued) and dental amalgam fillings. Its use in dental fillings has become controversial due to concerns about its potential toxicity.
2. In microbiology, Mercury is the name of a bacterial genus that includes the pathogenic species Mercury deserti and Mercury avium. These bacteria can cause infections in humans and animals.

It's important to note that when referring to the planet or the use of mercury in astrology, these are not related to medical definitions.

Chromium is an essential trace element that is necessary for human health. It is a key component of the glucose tolerance factor, which helps to enhance the function of insulin in regulating blood sugar levels. Chromium can be found in various foods such as meat, fish, whole grains, and some fruits and vegetables. However, it is also available in dietary supplements for those who may not get adequate amounts through their diet.

The recommended daily intake of chromium varies depending on age and gender. For adults, the adequate intake (AI) is 20-35 micrograms per day for women and 35-50 micrograms per day for men. Chromium deficiency is rare but can lead to impaired glucose tolerance, insulin resistance, and increased risk of developing type 2 diabetes.

It's important to note that while chromium supplements are marketed as a way to improve insulin sensitivity and blood sugar control, there is limited evidence to support these claims. Moreover, excessive intake of chromium can have adverse effects on health, including liver and kidney damage, stomach irritation, and hypoglycemia. Therefore, it's recommended to consult with a healthcare provider before taking any dietary supplements containing chromium.

I'm sorry for any confusion, but "Fluorocarbons" are not typically associated with medical definitions. Fluorocarbons are chemical compounds that contain carbon atoms bonded to fluorine atoms. They are often used in a variety of applications including refrigerants, fire extinguishing agents, and in the manufacturing of Teflon and other non-stick coatings.

If you have any medical terms or concepts you'd like me to define or explain, please let me know!

Pregnancy is a physiological state or condition where a fertilized egg (zygote) successfully implants and grows in the uterus of a woman, leading to the development of an embryo and finally a fetus. This process typically spans approximately 40 weeks, divided into three trimesters, and culminates in childbirth. Throughout this period, numerous hormonal and physical changes occur to support the growing offspring, including uterine enlargement, breast development, and various maternal adaptations to ensure the fetus's optimal growth and well-being.

Oxidative stress is defined as an imbalance between the production of reactive oxygen species (free radicals) and the body's ability to detoxify them or repair the damage they cause. This imbalance can lead to cellular damage, oxidation of proteins, lipids, and DNA, disruption of cellular functions, and activation of inflammatory responses. Prolonged or excessive oxidative stress has been linked to various health conditions, including cancer, cardiovascular diseases, neurodegenerative disorders, and aging-related diseases.

A dose-response relationship in the context of drugs refers to the changes in the effects or symptoms that occur as the dose of a drug is increased or decreased. Generally, as the dose of a drug is increased, the severity or intensity of its effects also increases. Conversely, as the dose is decreased, the effects of the drug become less severe or may disappear altogether.

The dose-response relationship is an important concept in pharmacology and toxicology because it helps to establish the safe and effective dosage range for a drug. By understanding how changes in the dose of a drug affect its therapeutic and adverse effects, healthcare providers can optimize treatment plans for their patients while minimizing the risk of harm.

The dose-response relationship is typically depicted as a curve that shows the relationship between the dose of a drug and its effect. The shape of the curve may vary depending on the drug and the specific effect being measured. Some drugs may have a steep dose-response curve, meaning that small changes in the dose can result in large differences in the effect. Other drugs may have a more gradual dose-response curve, where larger changes in the dose are needed to produce significant effects.

In addition to helping establish safe and effective dosages, the dose-response relationship is also used to evaluate the potential therapeutic benefits and risks of new drugs during clinical trials. By systematically testing different doses of a drug in controlled studies, researchers can identify the optimal dosage range for the drug and assess its safety and efficacy.

Hydrolases are a class of enzymes that help facilitate the breakdown of various types of chemical bonds through a process called hydrolysis, which involves the addition of water. These enzymes catalyze the cleavage of bonds in substrates by adding a molecule of water, leading to the formation of two or more smaller molecules.

Hydrolases play a crucial role in many biological processes, including digestion, metabolism, and detoxification. They can act on a wide range of substrates, such as proteins, lipids, carbohydrates, and nucleic acids, breaking them down into smaller units that can be more easily absorbed or utilized by the body.

Examples of hydrolases include:

1. Proteases: enzymes that break down proteins into smaller peptides or amino acids.
2. Lipases: enzymes that hydrolyze lipids, such as triglycerides, into fatty acids and glycerol.
3. Amylases: enzymes that break down complex carbohydrates, like starches, into simpler sugars, such as glucose.
4. Nucleases: enzymes that cleave nucleic acids, such as DNA or RNA, into smaller nucleotides or oligonucleotides.
5. Phosphatases: enzymes that remove phosphate groups from various substrates, including proteins and lipids.
6. Esterases: enzymes that hydrolyze ester bonds in a variety of substrates, such as those found in some drugs or neurotransmitters.

Hydrolases are essential for maintaining proper cellular function and homeostasis, and their dysregulation can contribute to various diseases and disorders.

The liver is a large, solid organ located in the upper right portion of the abdomen, beneath the diaphragm and above the stomach. It plays a vital role in several bodily functions, including:

1. Metabolism: The liver helps to metabolize carbohydrates, fats, and proteins from the food we eat into energy and nutrients that our bodies can use.
2. Detoxification: The liver detoxifies harmful substances in the body by breaking them down into less toxic forms or excreting them through bile.
3. Synthesis: The liver synthesizes important proteins, such as albumin and clotting factors, that are necessary for proper bodily function.
4. Storage: The liver stores glucose, vitamins, and minerals that can be released when the body needs them.
5. Bile production: The liver produces bile, a digestive juice that helps to break down fats in the small intestine.
6. Immune function: The liver plays a role in the immune system by filtering out bacteria and other harmful substances from the blood.

Overall, the liver is an essential organ that plays a critical role in maintaining overall health and well-being.

Indoor air pollution refers to the contamination of air within buildings and structures due to presence of particles, gases, or biological materials that can harmfully affect the health of occupants. These pollutants can originate from various sources including cooking stoves, heating systems, building materials, furniture, tobacco products, outdoor air, and microbial growth. Some common indoor air pollutants include particulate matter, carbon monoxide, nitrogen dioxide, sulfur dioxide, volatile organic compounds (VOCs), and mold. Prolonged exposure to these pollutants can cause a range of health issues, from respiratory problems to cancer, depending on the type and level of exposure. Effective ventilation, air filtration, and source control are some of the strategies used to reduce indoor air pollution.

Acetylcysteine is a medication that is used for its antioxidant effects and to help loosen thick mucus in the lungs. It is commonly used to treat conditions such as chronic bronchitis, emphysema, and cystic fibrosis. Acetylcysteine is also known by the brand names Mucomyst and Accolate. It works by thinning and breaking down mucus in the airways, making it easier to cough up and clear the airways. Additionally, acetylcysteine is an antioxidant that helps to protect cells from damage caused by free radicals. It is available as a oral tablet, liquid, or inhaled medication.

Occupational air pollutants refer to harmful substances present in the air in workplaces or occupational settings. These pollutants can include dusts, gases, fumes, vapors, or mists that are produced by industrial processes, chemical reactions, or other sources. Examples of occupational air pollutants include:

1. Respirable crystalline silica: A common mineral found in sand, stone, and concrete that can cause lung disease and cancer when inhaled in high concentrations.
2. Asbestos: A naturally occurring mineral fiber that was widely used in construction materials and industrial applications until the 1970s. Exposure to asbestos fibers can cause lung diseases such as asbestosis, lung cancer, and mesothelioma.
3. Welding fumes: Fumes generated during welding processes can contain harmful metals such as manganese, chromium, and nickel that can cause neurological damage and respiratory problems.
4. Isocyanates: Chemicals used in the production of foam insulation, spray-on coatings, and other industrial applications that can cause asthma and other respiratory symptoms.
5. Coal dust: Fine particles generated during coal mining, transportation, and handling that can cause lung disease and other health problems.
6. Diesel exhaust: Emissions from diesel engines that contain harmful particulates and gases that can cause respiratory and cardiovascular problems.

Occupational air pollutants are regulated by various government agencies, including the Occupational Safety and Health Administration (OSHA) in the United States, to protect workers from exposure and minimize health risks.

Epidemiological monitoring is the systematic and ongoing collection, analysis, interpretation, and dissemination of health data pertaining to a specific population or community, with the aim of identifying and tracking patterns of disease or injury, understanding their causes, and informing public health interventions and policies. This process typically involves the use of surveillance systems, such as disease registries, to collect data on the incidence, prevalence, and distribution of health outcomes of interest, as well as potential risk factors and exposures. The information generated through epidemiological monitoring can help to identify trends and emerging health threats, inform resource allocation and program planning, and evaluate the impact of public health interventions.

Aryl hydrocarbon hydroxylases (AHH) are a group of enzymes that play a crucial role in the metabolism of various aromatic and heterocyclic compounds, including potentially harmful substances such as polycyclic aromatic hydrocarbons (PAHs) and dioxins. These enzymes are primarily located in the endoplasmic reticulum of cells, particularly in the liver, but can also be found in other tissues.

The AHH enzymes catalyze the addition of a hydroxyl group (-OH) to the aromatic ring structure of these compounds, which is the first step in their biotransformation and eventual elimination from the body. This process can sometimes lead to the formation of metabolites that are more reactive and potentially toxic than the original compound. Therefore, the overall impact of AHH enzymes on human health is complex and depends on various factors, including the specific compounds being metabolized and individual genetic differences in enzyme activity.

Photochemical oxidants refer to chemical compounds that are formed as a result of a photochemical reaction, which involves the absorption of light. These oxidants are often highly reactive and can cause oxidative damage to living cells and tissues.

In the context of environmental science, photochemical oxidants are primarily associated with air pollution and the formation of ozone (O3) and other harmful oxidizing agents in the atmosphere. These pollutants are formed when nitrogen oxides (NOx) and volatile organic compounds (VOCs) react in the presence of sunlight, particularly ultraviolet (UV) radiation.

Photochemical oxidation can also occur in biological systems, such as within cells, where reactive oxygen species (ROS) can be generated by the absorption of light by certain molecules. These ROS can cause damage to cellular components, such as DNA, proteins, and lipids, and have been implicated in a variety of diseases, including cancer, cardiovascular disease, and neurodegenerative disorders.

Overall, photochemical oxidants are a significant concern in both environmental and health contexts, and understanding the mechanisms of their formation and effects is an important area of research.

Solvents, in a medical context, are substances that are capable of dissolving or dispersing other materials, often used in the preparation of medications and solutions. They are commonly organic chemicals that can liquefy various substances, making it possible to administer them in different forms, such as oral solutions, topical creams, or injectable drugs.

However, it is essential to recognize that solvents may pose health risks if mishandled or misused, particularly when they contain volatile organic compounds (VOCs). Prolonged exposure to these VOCs can lead to adverse health effects, including respiratory issues, neurological damage, and even cancer. Therefore, it is crucial to handle solvents with care and follow safety guidelines to minimize potential health hazards.

A lung is a pair of spongy, elastic organs in the chest that work together to enable breathing. They are responsible for taking in oxygen and expelling carbon dioxide through the process of respiration. The left lung has two lobes, while the right lung has three lobes. The lungs are protected by the ribcage and are covered by a double-layered membrane called the pleura. The trachea divides into two bronchi, which further divide into smaller bronchioles, leading to millions of tiny air sacs called alveoli, where the exchange of gases occurs.

High-performance liquid chromatography (HPLC) is a type of chromatography that separates and analyzes compounds based on their interactions with a stationary phase and a mobile phase under high pressure. The mobile phase, which can be a gas or liquid, carries the sample mixture through a column containing the stationary phase.

In HPLC, the mobile phase is a liquid, and it is pumped through the column at high pressures (up to several hundred atmospheres) to achieve faster separation times and better resolution than other types of liquid chromatography. The stationary phase can be a solid or a liquid supported on a solid, and it interacts differently with each component in the sample mixture, causing them to separate as they travel through the column.

HPLC is widely used in analytical chemistry, pharmaceuticals, biotechnology, and other fields to separate, identify, and quantify compounds present in complex mixtures. It can be used to analyze a wide range of substances, including drugs, hormones, vitamins, pigments, flavors, and pollutants. HPLC is also used in the preparation of pure samples for further study or use.

Glutathione transferases (GSTs) are a group of enzymes involved in the detoxification of xenobiotics and endogenous compounds. They facilitate the conjugation of these compounds with glutathione, a tripeptide consisting of cysteine, glutamic acid, and glycine, which results in more water-soluble products that can be easily excreted from the body.

GSTs play a crucial role in protecting cells against oxidative stress and chemical injury by neutralizing reactive electrophilic species and peroxides. They are found in various tissues, including the liver, kidneys, lungs, and intestines, and are classified into several families based on their structure and function.

Abnormalities in GST activity have been associated with increased susceptibility to certain diseases, such as cancer, neurological disorders, and respiratory diseases. Therefore, GSTs have become a subject of interest in toxicology, pharmacology, and clinical research.

In the context of medical and health sciences, particle size generally refers to the diameter or dimension of particles, which can be in the form of solid particles, droplets, or aerosols. These particles may include airborne pollutants, pharmaceutical drugs, or medical devices such as nanoparticles used in drug delivery systems.

Particle size is an important factor to consider in various medical applications because it can affect the behavior and interactions of particles with biological systems. For example, smaller particle sizes can lead to greater absorption and distribution throughout the body, while larger particle sizes may be filtered out by the body's natural defense mechanisms. Therefore, understanding particle size and its implications is crucial for optimizing the safety and efficacy of medical treatments and interventions.

I believe there may be some confusion in your question. "Organic chemicals" is a broad term that refers to chemical compounds containing carbon, often bonded to hydrogen. These can include natural substances like sugars and proteins, as well as synthetic materials like plastics and pharmaceuticals.

However, if you're asking about "organic" in the context of farming or food production, it refers to things that are produced without the use of synthetic pesticides, fertilizers, genetically modified organisms, irradiation, and sewage sludge.

In the field of medicine, there isn't a specific definition for 'organic chemicals'. If certain organic chemicals are used in medical contexts, they would be defined by their specific use or function (like a specific drug name).

"Prenatal exposure delayed effects" refer to the adverse health outcomes or symptoms that become apparent in an individual during their development or later in life, which are caused by exposure to certain environmental factors or substances while they were still in the womb. These effects may not be immediately observable at birth and can take weeks, months, years, or even decades to manifest. They can result from maternal exposure to various agents such as infectious diseases, medications, illicit drugs, tobacco smoke, alcohol, or environmental pollutants during pregnancy. The delayed effects can impact multiple organ systems and may include physical, cognitive, behavioral, and developmental abnormalities. It is important to note that the risk and severity of these effects can depend on several factors, including the timing, duration, and intensity of the exposure, as well as the individual's genetic susceptibility.

Enzyme induction is a process by which the activity or expression of an enzyme is increased in response to some stimulus, such as a drug, hormone, or other environmental factor. This can occur through several mechanisms, including increasing the transcription of the enzyme's gene, stabilizing the mRNA that encodes the enzyme, or increasing the translation of the mRNA into protein.

In some cases, enzyme induction can be a beneficial process, such as when it helps the body to metabolize and clear drugs more quickly. However, in other cases, enzyme induction can have negative consequences, such as when it leads to the increased metabolism of important endogenous compounds or the activation of harmful procarcinogens.

Enzyme induction is an important concept in pharmacology and toxicology, as it can affect the efficacy and safety of drugs and other xenobiotics. It is also relevant to the study of drug interactions, as the induction of one enzyme by a drug can lead to altered metabolism and effects of another drug that is metabolized by the same enzyme.

DNA damage refers to any alteration in the structure or composition of deoxyribonucleic acid (DNA), which is the genetic material present in cells. DNA damage can result from various internal and external factors, including environmental exposures such as ultraviolet radiation, tobacco smoke, and certain chemicals, as well as normal cellular processes such as replication and oxidative metabolism.

Examples of DNA damage include base modifications, base deletions or insertions, single-strand breaks, double-strand breaks, and crosslinks between the two strands of the DNA helix. These types of damage can lead to mutations, genomic instability, and chromosomal aberrations, which can contribute to the development of diseases such as cancer, neurodegenerative disorders, and aging-related conditions.

The body has several mechanisms for repairing DNA damage, including base excision repair, nucleotide excision repair, mismatch repair, and double-strand break repair. However, if the damage is too extensive or the repair mechanisms are impaired, the cell may undergo apoptosis (programmed cell death) to prevent the propagation of potentially harmful mutations.

Reactive Oxygen Species (ROS) are highly reactive molecules containing oxygen, including peroxides, superoxide, hydroxyl radical, and singlet oxygen. They are naturally produced as byproducts of normal cellular metabolism in the mitochondria, and can also be generated by external sources such as ionizing radiation, tobacco smoke, and air pollutants. At low or moderate concentrations, ROS play important roles in cell signaling and homeostasis, but at high concentrations, they can cause significant damage to cell structures, including lipids, proteins, and DNA, leading to oxidative stress and potential cell death.

Reproduction, in the context of biology and medicine, refers to the process by which organisms produce offspring. It is a complex process that involves the creation, development, and growth of new individuals from parent organisms. In sexual reproduction, this process typically involves the combination of genetic material from two parents through the fusion of gametes (sex cells) such as sperm and egg cells. This results in the formation of a zygote, which then develops into a new individual with a unique genetic makeup.

In contrast, asexual reproduction does not involve the fusion of gametes and can occur through various mechanisms such as budding, fragmentation, or parthenogenesis. Asexual reproduction results in offspring that are genetically identical to the parent organism.

Reproduction is a fundamental process that ensures the survival and continuation of species over time. It is also an area of active research in fields such as reproductive medicine, where scientists and clinicians work to understand and address issues related to human fertility, contraception, and genetic disorders.

Respiratory tract diseases refer to a broad range of medical conditions that affect the respiratory system, which includes the nose, throat (pharynx), windpipe (trachea), bronchi, bronchioles, and lungs. These diseases can be categorized into upper and lower respiratory tract infections based on the location of the infection.

Upper respiratory tract infections affect the nose, sinuses, pharynx, and larynx, and include conditions such as the common cold, flu, sinusitis, and laryngitis. Symptoms often include nasal congestion, sore throat, cough, and fever.

Lower respiratory tract infections affect the trachea, bronchi, bronchioles, and lungs, and can be more severe. They include conditions such as pneumonia, bronchitis, and tuberculosis. Symptoms may include cough, chest congestion, shortness of breath, and fever.

Respiratory tract diseases can also be caused by allergies, irritants, or genetic factors. Treatment varies depending on the specific condition and severity but may include medications, breathing treatments, or surgery in severe cases.

Oxidation-Reduction (redox) reactions are a type of chemical reaction involving a transfer of electrons between two species. The substance that loses electrons in the reaction is oxidized, and the substance that gains electrons is reduced. Oxidation and reduction always occur together in a redox reaction, hence the term "oxidation-reduction."

In biological systems, redox reactions play a crucial role in many cellular processes, including energy production, metabolism, and signaling. The transfer of electrons in these reactions is often facilitated by specialized molecules called electron carriers, such as nicotinamide adenine dinucleotide (NAD+/NADH) and flavin adenine dinucleotide (FAD/FADH2).

The oxidation state of an element in a compound is a measure of the number of electrons that have been gained or lost relative to its neutral state. In redox reactions, the oxidation state of one or more elements changes as they gain or lose electrons. The substance that is oxidized has a higher oxidation state, while the substance that is reduced has a lower oxidation state.

Overall, oxidation-reduction reactions are fundamental to the functioning of living organisms and are involved in many important biological processes.

I believe there may be a misunderstanding in your question. "Cities" is not a medical term or concept, but rather a geographical and sociopolitical one referring to large, densely populated urban areas. If you're looking for information about health-related topics associated with cities, I would be happy to help! For example, there are many public health issues that are closely linked to city living, such as air pollution, infectious diseases, and chronic conditions like obesity and heart disease. Please let me know if you have any specific questions in mind!

The United States Environmental Protection Agency (EPA) is not a medical term or concept. However, I can provide you with a general definition:

The EPA is an independent agency of the federal government of the United States, responsible for protecting public health and the environment by enforcing regulations based on federal laws. The agency conducts environmental assessment, education, research, and regulation of various voluntary and compulsory programs in the US to address issues related to toxic substances, air and water quality, solid waste management, radiation protection, and hazardous waste management.

Risk assessment in the medical context refers to the process of identifying, evaluating, and prioritizing risks to patients, healthcare workers, or the community related to healthcare delivery. It involves determining the likelihood and potential impact of adverse events or hazards, such as infectious diseases, medication errors, or medical devices failures, and implementing measures to mitigate or manage those risks. The goal of risk assessment is to promote safe and high-quality care by identifying areas for improvement and taking action to minimize harm.

Antioxidants are substances that can prevent or slow damage to cells caused by free radicals, which are unstable molecules that the body produces as a reaction to environmental and other pressures. Antioxidants are able to neutralize free radicals by donating an electron to them, thus stabilizing them and preventing them from causing further damage to the cells.

Antioxidants can be found in a variety of foods, including fruits, vegetables, nuts, and grains. Some common antioxidants include vitamins C and E, beta-carotene, and selenium. Antioxidants are also available as dietary supplements.

In addition to their role in protecting cells from damage, antioxidants have been studied for their potential to prevent or treat a number of health conditions, including cancer, heart disease, and age-related macular degeneration. However, more research is needed to fully understand the potential benefits and risks of using antioxidant supplements.

A newborn infant is a baby who is within the first 28 days of life. This period is also referred to as the neonatal period. Newborns require specialized care and attention due to their immature bodily systems and increased vulnerability to various health issues. They are closely monitored for signs of well-being, growth, and development during this critical time.

A biological marker, often referred to as a biomarker, is a measurable indicator that reflects the presence or severity of a disease state, or a response to a therapeutic intervention. Biomarkers can be found in various materials such as blood, tissues, or bodily fluids, and they can take many forms, including molecular, histologic, radiographic, or physiological measurements.

In the context of medical research and clinical practice, biomarkers are used for a variety of purposes, such as:

1. Diagnosis: Biomarkers can help diagnose a disease by indicating the presence or absence of a particular condition. For example, prostate-specific antigen (PSA) is a biomarker used to detect prostate cancer.
2. Monitoring: Biomarkers can be used to monitor the progression or regression of a disease over time. For instance, hemoglobin A1c (HbA1c) levels are monitored in diabetes patients to assess long-term blood glucose control.
3. Predicting: Biomarkers can help predict the likelihood of developing a particular disease or the risk of a negative outcome. For example, the presence of certain genetic mutations can indicate an increased risk for breast cancer.
4. Response to treatment: Biomarkers can be used to evaluate the effectiveness of a specific treatment by measuring changes in the biomarker levels before and after the intervention. This is particularly useful in personalized medicine, where treatments are tailored to individual patients based on their unique biomarker profiles.

It's important to note that for a biomarker to be considered clinically valid and useful, it must undergo rigorous validation through well-designed studies, including demonstrating sensitivity, specificity, reproducibility, and clinical relevance.

In the field of medicine, "time factors" refer to the duration of symptoms or time elapsed since the onset of a medical condition, which can have significant implications for diagnosis and treatment. Understanding time factors is crucial in determining the progression of a disease, evaluating the effectiveness of treatments, and making critical decisions regarding patient care.

For example, in stroke management, "time is brain," meaning that rapid intervention within a specific time frame (usually within 4.5 hours) is essential to administering tissue plasminogen activator (tPA), a clot-busting drug that can minimize brain damage and improve patient outcomes. Similarly, in trauma care, the "golden hour" concept emphasizes the importance of providing definitive care within the first 60 minutes after injury to increase survival rates and reduce morbidity.

Time factors also play a role in monitoring the progression of chronic conditions like diabetes or heart disease, where regular follow-ups and assessments help determine appropriate treatment adjustments and prevent complications. In infectious diseases, time factors are crucial for initiating antibiotic therapy and identifying potential outbreaks to control their spread.

Overall, "time factors" encompass the significance of recognizing and acting promptly in various medical scenarios to optimize patient outcomes and provide effective care.

Glutathione is a tripeptide composed of three amino acids: cysteine, glutamic acid, and glycine. It is a vital antioxidant that plays an essential role in maintaining cellular health and function. Glutathione helps protect cells from oxidative stress by neutralizing free radicals, which are unstable molecules that can damage cells and contribute to aging and diseases such as cancer, heart disease, and dementia. It also supports the immune system, detoxifies harmful substances, and regulates various cellular processes, including DNA synthesis and repair.

Glutathione is found in every cell of the body, with particularly high concentrations in the liver, lungs, and eyes. The body can produce its own glutathione, but levels may decline with age, illness, or exposure to toxins. As such, maintaining optimal glutathione levels through diet, supplementation, or other means is essential for overall health and well-being.

An Atmosphere Exposure Chamber (AEC) is a controlled environment chamber that is designed to expose materials, products, or devices to specific atmospheric conditions for the purpose of testing their durability, performance, and safety. These chambers can simulate various environmental factors such as temperature, humidity, pressure, and contaminants, allowing researchers and manufacturers to evaluate how these factors may affect the properties and behavior of the materials being tested.

AECs are commonly used in a variety of industries, including automotive, aerospace, electronics, and medical devices, to ensure that products meet regulatory requirements and industry standards for performance and safety. For example, an AEC might be used to test the durability of a new aircraft material under extreme temperature and humidity conditions, or to evaluate the performance of a medical device in a contaminated environment.

The design and operation of AECs are subject to various regulations and standards, such as those established by organizations like the International Organization for Standardization (ISO), the American Society for Testing and Materials (ASTM), and the Society of Automotive Engineers (SAE). These standards ensure that AECs are designed and operated in a consistent and controlled manner, allowing for accurate and reliable test results.

Biological models, also known as physiological models or organismal models, are simplified representations of biological systems, processes, or mechanisms that are used to understand and explain the underlying principles and relationships. These models can be theoretical (conceptual or mathematical) or physical (such as anatomical models, cell cultures, or animal models). They are widely used in biomedical research to study various phenomena, including disease pathophysiology, drug action, and therapeutic interventions.

Examples of biological models include:

1. Mathematical models: These use mathematical equations and formulas to describe complex biological systems or processes, such as population dynamics, metabolic pathways, or gene regulation networks. They can help predict the behavior of these systems under different conditions and test hypotheses about their underlying mechanisms.
2. Cell cultures: These are collections of cells grown in a controlled environment, typically in a laboratory dish or flask. They can be used to study cellular processes, such as signal transduction, gene expression, or metabolism, and to test the effects of drugs or other treatments on these processes.
3. Animal models: These are living organisms, usually vertebrates like mice, rats, or non-human primates, that are used to study various aspects of human biology and disease. They can provide valuable insights into the pathophysiology of diseases, the mechanisms of drug action, and the safety and efficacy of new therapies.
4. Anatomical models: These are physical representations of biological structures or systems, such as plastic models of organs or tissues, that can be used for educational purposes or to plan surgical procedures. They can also serve as a basis for developing more sophisticated models, such as computer simulations or 3D-printed replicas.

Overall, biological models play a crucial role in advancing our understanding of biology and medicine, helping to identify new targets for therapeutic intervention, develop novel drugs and treatments, and improve human health.

Organ size refers to the volume or physical measurement of an organ in the body of an individual. It can be described in terms of length, width, and height or by using specialized techniques such as imaging studies (like CT scans or MRIs) to determine the volume. The size of an organ can vary depending on factors such as age, sex, body size, and overall health status. Changes in organ size may indicate various medical conditions, including growths, inflammation, or atrophy.

Carbon monoxide (CO) is a colorless, odorless, and tasteless gas that is slightly less dense than air. It is toxic to hemoglobic animals when encountered in concentrations above about 35 ppm. This compound is a product of incomplete combustion of organic matter, and is a major component of automobile exhaust.

Carbon monoxide is poisonous because it binds to hemoglobin in red blood cells much more strongly than oxygen does, forming carboxyhemoglobin. This prevents the transport of oxygen throughout the body, which can lead to suffocation and death. Symptoms of carbon monoxide poisoning include headache, dizziness, weakness, nausea, vomiting, confusion, and disorientation. Prolonged exposure can lead to unconsciousness and death.

Carbon monoxide detectors are commonly used in homes and other buildings to alert occupants to the presence of this dangerous gas. It is important to ensure that these devices are functioning properly and that they are placed in appropriate locations throughout the building. Additionally, it is essential to maintain appliances and heating systems to prevent the release of carbon monoxide into living spaces.

Stereoisomerism is a type of isomerism (structural arrangement of atoms) in which molecules have the same molecular formula and sequence of bonded atoms, but differ in the three-dimensional orientation of their atoms in space. This occurs when the molecule contains asymmetric carbon atoms or other rigid structures that prevent free rotation, leading to distinct spatial arrangements of groups of atoms around a central point. Stereoisomers can have different chemical and physical properties, such as optical activity, boiling points, and reactivities, due to differences in their shape and the way they interact with other molecules.

There are two main types of stereoisomerism: enantiomers (mirror-image isomers) and diastereomers (non-mirror-image isomers). Enantiomers are pairs of stereoisomers that are mirror images of each other, but cannot be superimposed on one another. Diastereomers, on the other hand, are non-mirror-image stereoisomers that have different physical and chemical properties.

Stereoisomerism is an important concept in chemistry and biology, as it can affect the biological activity of molecules, such as drugs and natural products. For example, some enantiomers of a drug may be active, while others are inactive or even toxic. Therefore, understanding stereoisomerism is crucial for designing and synthesizing effective and safe drugs.

Microsomes, liver refers to a subcellular fraction of liver cells (hepatocytes) that are obtained during tissue homogenization and subsequent centrifugation. These microsomal fractions are rich in membranous structures known as the endoplasmic reticulum (ER), particularly the rough ER. They are involved in various important cellular processes, most notably the metabolism of xenobiotics (foreign substances) including drugs, toxins, and carcinogens.

The liver microsomes contain a variety of enzymes, such as cytochrome P450 monooxygenases, that are crucial for phase I drug metabolism. These enzymes help in the oxidation, reduction, or hydrolysis of xenobiotics, making them more water-soluble and facilitating their excretion from the body. Additionally, liver microsomes also host other enzymes involved in phase II conjugation reactions, where the metabolites from phase I are further modified by adding polar molecules like glucuronic acid, sulfate, or acetyl groups.

In summary, liver microsomes are a subcellular fraction of liver cells that play a significant role in the metabolism and detoxification of xenobiotics, contributing to the overall protection and maintenance of cellular homeostasis within the body.

A cell line is a culture of cells that are grown in a laboratory for use in research. These cells are usually taken from a single cell or group of cells, and they are able to divide and grow continuously in the lab. Cell lines can come from many different sources, including animals, plants, and humans. They are often used in scientific research to study cellular processes, disease mechanisms, and to test new drugs or treatments. Some common types of human cell lines include HeLa cells (which come from a cancer patient named Henrietta Lacks), HEK293 cells (which come from embryonic kidney cells), and HUVEC cells (which come from umbilical vein endothelial cells). It is important to note that cell lines are not the same as primary cells, which are cells that are taken directly from a living organism and have not been grown in the lab.

C57BL/6 (C57 Black 6) is an inbred strain of laboratory mouse that is widely used in biomedical research. The term "inbred" refers to a strain of animals where matings have been carried out between siblings or other closely related individuals for many generations, resulting in a population that is highly homozygous at most genetic loci.

The C57BL/6 strain was established in 1920 by crossing a female mouse from the dilute brown (DBA) strain with a male mouse from the black strain. The resulting offspring were then interbred for many generations to create the inbred C57BL/6 strain.

C57BL/6 mice are known for their robust health, longevity, and ease of handling, making them a popular choice for researchers. They have been used in a wide range of biomedical research areas, including studies of cancer, immunology, neuroscience, cardiovascular disease, and metabolism.

One of the most notable features of the C57BL/6 strain is its sensitivity to certain genetic modifications, such as the introduction of mutations that lead to obesity or impaired glucose tolerance. This has made it a valuable tool for studying the genetic basis of complex diseases and traits.

Overall, the C57BL/6 inbred mouse strain is an important model organism in biomedical research, providing a valuable resource for understanding the genetic and molecular mechanisms underlying human health and disease.

Hazardous substances, in a medical context, refer to agents that pose a risk to the health of living organisms. These can include chemicals, biological agents (such as bacteria or viruses), and physical hazards (like radiation). Exposure to these substances can lead to a range of adverse health effects, from acute symptoms like irritation and poisoning to chronic conditions such as cancer, neurological disorders, or genetic mutations.

The classification and regulation of hazardous substances are often based on their potential for harm, the severity of the associated health risks, and the conditions under which they become dangerous. These assessments help inform safety measures, exposure limits, and handling procedures to minimize risks in occupational, environmental, and healthcare settings.

Dichlorodiphenyl dichloroethylene (DDE) is a chemical compound that is formed as a byproduct when dichlorodiphenyltrichloroethane (DDT) is metabolized or breaks down in the environment. DDE is an organochlorine pesticide and is similar in structure to DDT, with two phenyl rings and two chlorine atoms attached to a central ethylene molecule.

DDE is highly stable and does not break down easily in the environment, which means that it can persist for many years and accumulate in the food chain. It is lipophilic, meaning that it tends to accumulate in fatty tissues, and bioaccumulates in animals that are higher up in the food chain.

DDE has been shown to have toxic effects on both wildlife and humans. It can disrupt hormone systems, particularly those related to reproduction, and has been linked to reproductive problems in birds and other animals. In humans, exposure to DDE has been associated with increased risk of certain cancers, developmental delays in children, and other health problems.

DDE is no longer used as a pesticide in many countries, but it can still be found in the environment due to its persistence and ability to accumulate in the food chain. People can be exposed to DDE through contaminated food, water, or air, as well as through contact with soil or dust that contains DDE.

"Air movements" is not a medical term or concept. It generally refers to the movement or circulation of air, which can occur naturally (such as through wind) or mechanically (such as through fans or ventilation systems). In some contexts, it may refer specifically to the movement of air in operating rooms or other controlled environments for medical purposes. However, without more specific context, it is difficult to provide a precise definition or medical interpretation of "air movements."

Urban health is a branch of public health that focuses on the unique health challenges and disparities faced by urban populations. It encompasses the physical, mental, and social well-being of people living in urban areas, which are characterized by high population density, diverse cultural and socioeconomic backgrounds, and unique environmental exposures.

Urban health addresses a range of issues, including infectious diseases, chronic conditions, injuries, violence, and mental health disorders, as well as the social determinants of health such as housing, education, income, and access to healthcare services. It also considers the impact of urbanization on health, including the effects of pollution, noise, crowding, and lack of green spaces.

The goal of urban health is to promote health equity and improve the overall health outcomes of urban populations by addressing these challenges through evidence-based interventions, policies, and programs that are tailored to the unique needs of urban communities.

"Cells, cultured" is a medical term that refers to cells that have been removed from an organism and grown in controlled laboratory conditions outside of the body. This process is called cell culture and it allows scientists to study cells in a more controlled and accessible environment than they would have inside the body. Cultured cells can be derived from a variety of sources, including tissues, organs, or fluids from humans, animals, or cell lines that have been previously established in the laboratory.

Cell culture involves several steps, including isolation of the cells from the tissue, purification and characterization of the cells, and maintenance of the cells in appropriate growth conditions. The cells are typically grown in specialized media that contain nutrients, growth factors, and other components necessary for their survival and proliferation. Cultured cells can be used for a variety of purposes, including basic research, drug development and testing, and production of biological products such as vaccines and gene therapies.

It is important to note that cultured cells may behave differently than they do in the body, and results obtained from cell culture studies may not always translate directly to human physiology or disease. Therefore, it is essential to validate findings from cell culture experiments using additional models and ultimately in clinical trials involving human subjects.

I'm sorry for any confusion, but "weather" is not a medical term. Weather refers to the state of the atmosphere at a particular place and time, including factors such as temperature, humidity, cloudiness, precipitation, and wind. If you have any questions about medical terms or concepts, I would be happy to try to help answer those for you!

Acid rain is a form of precipitation, including rain, snow, and fog, that has a pH level less than 5.6 and contains high levels of sulfuric and nitric acids. These acidic compounds are formed primarily when sulfur dioxide (SO2) and nitrogen oxides (NOx) are emitted into the atmosphere from human sources such as coal-fired power plants, industrial processes, and transportation vehicles. When these pollutants mix with water, oxygen, and other chemicals in the atmosphere, they form acidic compounds that can fall to the earth as acid rain, harming both natural ecosystems and man-made structures.

The term "acid rain" was first coined in the 1960s by scientists studying the effects of air pollution on the environment. Acid rain can have a number of negative impacts on the environment, including damaging forests, lakes, and streams; harming aquatic life; eroding buildings, monuments, and sculptures; and contributing to respiratory problems in humans and animals.

To mitigate the effects of acid rain, many countries have implemented regulations aimed at reducing emissions of sulfur dioxide and nitrogen oxides from industrial sources and power plants. These efforts have helped to reduce the severity of acid rain in some areas, but the problem remains a significant concern in many parts of the world.

'Gene expression regulation' refers to the processes that control whether, when, and where a particular gene is expressed, meaning the production of a specific protein or functional RNA encoded by that gene. This complex mechanism can be influenced by various factors such as transcription factors, chromatin remodeling, DNA methylation, non-coding RNAs, and post-transcriptional modifications, among others. Proper regulation of gene expression is crucial for normal cellular function, development, and maintaining homeostasis in living organisms. Dysregulation of gene expression can lead to various diseases, including cancer and genetic disorders.

In medical terms, gases refer to the state of matter that has no fixed shape or volume and expands to fill any container it is placed in. Gases in the body can be normal, such as the oxygen, carbon dioxide, and nitrogen that are present in the lungs and blood, or abnormal, such as gas that accumulates in the digestive tract due to conditions like bloating or swallowing air.

Gases can also be used medically for therapeutic purposes, such as in the administration of anesthesia or in the treatment of certain respiratory conditions with oxygen therapy. Additionally, measuring the amount of gas in the body, such as through imaging studies like X-rays or CT scans, can help diagnose various medical conditions.

Cell survival refers to the ability of a cell to continue living and functioning normally, despite being exposed to potentially harmful conditions or treatments. This can include exposure to toxins, radiation, chemotherapeutic drugs, or other stressors that can damage cells or interfere with their normal processes.

In scientific research, measures of cell survival are often used to evaluate the effectiveness of various therapies or treatments. For example, researchers may expose cells to a particular drug or treatment and then measure the percentage of cells that survive to assess its potential therapeutic value. Similarly, in toxicology studies, measures of cell survival can help to determine the safety of various chemicals or substances.

It's important to note that cell survival is not the same as cell proliferation, which refers to the ability of cells to divide and multiply. While some treatments may promote cell survival, they may also inhibit cell proliferation, making them useful for treating diseases such as cancer. Conversely, other treatments may be designed to specifically target and kill cancer cells, even if it means sacrificing some healthy cells in the process.

Nitric acid is not a medical term, but it is a chemical compound with the formula HNO3. It is a highly corrosive mineral acid and is the primary constituent of nitric acid solutions.

Medically, nitric acid or its salts may be mentioned in the context of certain medical conditions or treatments. For example, nitrate or nitrite salts of potassium or sodium can be used as vasodilators to treat angina pectoris (chest pain) by improving blood flow and reducing oxygen demand in the heart muscle. Nitric acid itself is not used medically.

It's important to note that exposure to nitric acid can cause severe burns and tissue damage, so it should be handled with care and appropriate personal protective equipment.

Messenger RNA (mRNA) is a type of RNA (ribonucleic acid) that carries genetic information copied from DNA in the form of a series of three-base code "words," each of which specifies a particular amino acid. This information is used by the cell's machinery to construct proteins, a process known as translation. After being transcribed from DNA, mRNA travels out of the nucleus to the ribosomes in the cytoplasm where protein synthesis occurs. Once the protein has been synthesized, the mRNA may be degraded and recycled. Post-transcriptional modifications can also occur to mRNA, such as alternative splicing and addition of a 5' cap and a poly(A) tail, which can affect its stability, localization, and translation efficiency.

Molecular sequence data refers to the specific arrangement of molecules, most commonly nucleotides in DNA or RNA, or amino acids in proteins, that make up a biological macromolecule. This data is generated through laboratory techniques such as sequencing, and provides information about the exact order of the constituent molecules. This data is crucial in various fields of biology, including genetics, evolution, and molecular biology, allowing for comparisons between different organisms, identification of genetic variations, and studies of gene function and regulation.

Sulfur oxides (SOx) are chemical compounds that contain sulfur and oxygen in various oxidation states. The term "sulfur oxides" is often used to refer specifically to sulfur dioxide (SO2) and sulfur trioxide (SO3), which are the most common and widely studied SOx compounds.

Sulfur dioxide is a colorless gas with a sharp, pungent odor. It is produced naturally by volcanic eruptions and is also released into the air when fossil fuels such as coal and oil are burned for electricity generation, industrial processes, and transportation. Exposure to high levels of sulfur dioxide can cause respiratory symptoms such as coughing, wheezing, and shortness of breath.

Sulfur trioxide is a colorless liquid or solid with a pungent, choking odor. It is produced industrially for the manufacture of sulfuric acid and other chemicals. Sulfur trioxide is highly reactive and can cause severe burns and eye damage upon contact.

Both sulfur dioxide and sulfur trioxide contribute to air pollution and have been linked to a range of health and environmental effects, including respiratory problems, acid rain, and damage to crops and forests. As a result, there are regulations in place to limit emissions of these pollutants into the air.

Reverse Transcriptase Polymerase Chain Reaction (RT-PCR) is a laboratory technique used in molecular biology to amplify and detect specific DNA sequences. This technique is particularly useful for the detection and quantification of RNA viruses, as well as for the analysis of gene expression.

The process involves two main steps: reverse transcription and polymerase chain reaction (PCR). In the first step, reverse transcriptase enzyme is used to convert RNA into complementary DNA (cDNA) by reading the template provided by the RNA molecule. This cDNA then serves as a template for the PCR amplification step.

In the second step, the PCR reaction uses two primers that flank the target DNA sequence and a thermostable polymerase enzyme to repeatedly copy the targeted cDNA sequence. The reaction mixture is heated and cooled in cycles, allowing the primers to anneal to the template, and the polymerase to extend the new strand. This results in exponential amplification of the target DNA sequence, making it possible to detect even small amounts of RNA or cDNA.

RT-PCR is a sensitive and specific technique that has many applications in medical research and diagnostics, including the detection of viruses such as HIV, hepatitis C virus, and SARS-CoV-2 (the virus that causes COVID-19). It can also be used to study gene expression, identify genetic mutations, and diagnose genetic disorders.

I'm sorry for any confusion, but "Meteorological Concepts" is quite broad and can refer to various ideas and phenomena related to the study of meteorology, which is the scientific discipline that deals with the atmosphere and its processes. Here are a few examples of meteorological concepts:

1. Air pressure: The force exerted by the weight of the air above a given point. It's usually measured in hectopascals (hPa), inches of mercury (inHg), or millibars (mbar).
2. Temperature: A measure of the warmth or coldness of an object or environment, often reported in degrees Celsius (°C) or Fahrenheit (°F).
3. Humidity: The amount of water vapor present in the air. Relative humidity is the ratio of the current water vapor content to the maximum possible content at a given temperature.
4. Precipitation: Any form of water that falls from the atmosphere and reaches the ground, including rain, snow, sleet, or hail.
5. Wind: The horizontal movement of air relative to the surface of the Earth. It's usually described in terms of its speed (measured in knots, miles per hour, or meters per second) and direction (often given as a compass bearing).
6. Clouds: Visible masses of water droplets or ice crystals suspended in the atmosphere. They form due to the condensation of atmospheric water vapor and are classified based on their appearance, altitude, and other characteristics.
7. Fronts: Boundaries between different air masses that have distinct temperature and humidity properties. These boundaries can lead to various weather phenomena, such as precipitation and severe thunderstorms.
8. Air pollution: The presence of harmful substances in the atmosphere, often resulting from human activities like industrial processes or transportation.
9. Weather forecasting: The use of scientific principles, observations, and computer models to predict future weather conditions.
10. Climate: The long-term average of weather patterns and conditions in a specific region, typically over a period of 30 years or more.

These are just a few examples of meteorological concepts. There are many more aspects of atmospheric science that could be explored, such as the study of tornadoes, hurricanes, and other extreme weather events.

Apoptosis is a programmed and controlled cell death process that occurs in multicellular organisms. It is a natural process that helps maintain tissue homeostasis by eliminating damaged, infected, or unwanted cells. During apoptosis, the cell undergoes a series of morphological changes, including cell shrinkage, chromatin condensation, and fragmentation into membrane-bound vesicles called apoptotic bodies. These bodies are then recognized and engulfed by neighboring cells or phagocytic cells, preventing an inflammatory response. Apoptosis is regulated by a complex network of intracellular signaling pathways that involve proteins such as caspases, Bcl-2 family members, and inhibitors of apoptosis (IAPs).

Signal transduction is the process by which a cell converts an extracellular signal, such as a hormone or neurotransmitter, into an intracellular response. This involves a series of molecular events that transmit the signal from the cell surface to the interior of the cell, ultimately resulting in changes in gene expression, protein activity, or metabolism.

The process typically begins with the binding of the extracellular signal to a receptor located on the cell membrane. This binding event activates the receptor, which then triggers a cascade of intracellular signaling molecules, such as second messengers, protein kinases, and ion channels. These molecules amplify and propagate the signal, ultimately leading to the activation or inhibition of specific cellular responses.

Signal transduction pathways are highly regulated and can be modulated by various factors, including other signaling molecules, post-translational modifications, and feedback mechanisms. Dysregulation of these pathways has been implicated in a variety of diseases, including cancer, diabetes, and neurological disorders.

Nitrogen oxides (NOx) are a group of highly reactive gases, primarily composed of nitric oxide (NO) and nitrogen dioxide (NO2). They are formed during the combustion of fossil fuels, such as coal, oil, gas, or biomass, and are emitted from various sources, including power plants, industrial boilers, transportation vehicles, and residential heating systems. Exposure to NOx can have adverse health effects, particularly on the respiratory system, and contribute to the formation of harmful air pollutants like ground-level ozone and fine particulate matter.

Deoxyribonucleic acid (DNA) is the genetic material present in the cells of organisms where it is responsible for the storage and transmission of hereditary information. DNA is a long molecule that consists of two strands coiled together to form a double helix. Each strand is made up of a series of four nucleotide bases - adenine (A), guanine (G), cytosine (C), and thymine (T) - that are linked together by phosphate and sugar groups. The sequence of these bases along the length of the molecule encodes genetic information, with A always pairing with T and C always pairing with G. This base-pairing allows for the replication and transcription of DNA, which are essential processes in the functioning and reproduction of all living organisms.

Western blotting is a laboratory technique used in molecular biology to detect and quantify specific proteins in a mixture of many different proteins. This technique is commonly used to confirm the expression of a protein of interest, determine its size, and investigate its post-translational modifications. The name "Western" blotting distinguishes this technique from Southern blotting (for DNA) and Northern blotting (for RNA).

The Western blotting procedure involves several steps:

1. Protein extraction: The sample containing the proteins of interest is first extracted, often by breaking open cells or tissues and using a buffer to extract the proteins.
2. Separation of proteins by electrophoresis: The extracted proteins are then separated based on their size by loading them onto a polyacrylamide gel and running an electric current through the gel (a process called sodium dodecyl sulfate-polyacrylamide gel electrophoresis or SDS-PAGE). This separates the proteins according to their molecular weight, with smaller proteins migrating faster than larger ones.
3. Transfer of proteins to a membrane: After separation, the proteins are transferred from the gel onto a nitrocellulose or polyvinylidene fluoride (PVDF) membrane using an electric current in a process called blotting. This creates a replica of the protein pattern on the gel but now immobilized on the membrane for further analysis.
4. Blocking: The membrane is then blocked with a blocking agent, such as non-fat dry milk or bovine serum albumin (BSA), to prevent non-specific binding of antibodies in subsequent steps.
5. Primary antibody incubation: A primary antibody that specifically recognizes the protein of interest is added and allowed to bind to its target protein on the membrane. This step may be performed at room temperature or 4°C overnight, depending on the antibody's properties.
6. Washing: The membrane is washed with a buffer to remove unbound primary antibodies.
7. Secondary antibody incubation: A secondary antibody that recognizes the primary antibody (often coupled to an enzyme or fluorophore) is added and allowed to bind to the primary antibody. This step may involve using a horseradish peroxidase (HRP)-conjugated or alkaline phosphatase (AP)-conjugated secondary antibody, depending on the detection method used later.
8. Washing: The membrane is washed again to remove unbound secondary antibodies.
9. Detection: A detection reagent is added to visualize the protein of interest by detecting the signal generated from the enzyme-conjugated or fluorophore-conjugated secondary antibody. This can be done using chemiluminescent, colorimetric, or fluorescent methods.
10. Analysis: The resulting image is analyzed to determine the presence and quantity of the protein of interest in the sample.

Western blotting is a powerful technique for identifying and quantifying specific proteins within complex mixtures. It can be used to study protein expression, post-translational modifications, protein-protein interactions, and more. However, it requires careful optimization and validation to ensure accurate and reproducible results.

Ventilation, in the context of medicine and physiology, refers to the process of breathing, which is the exchange of air between the lungs and the environment. It involves both inspiration (inhaling) and expiration (exhaling). During inspiration, air moves into the lungs, delivering oxygen to the alveoli (air sacs) where gas exchange occurs. Oxygen is taken up by the blood and transported to the body's cells, while carbon dioxide, a waste product, is expelled from the body during expiration.

In a medical setting, ventilation may also refer to the use of mechanical devices, such as ventilators or respirators, which assist or replace the breathing process for patients who are unable to breathe effectively on their own due to conditions like respiratory failure, sedation, neuromuscular disorders, or injuries. These machines help maintain adequate gas exchange and prevent complications associated with inadequate ventilation, such as hypoxia (low oxygen levels) and hypercapnia (high carbon dioxide levels).

'Smog' is not a term used in medical definitions. It is a combination of the words "smoke" and "fog" and refers to a type of air pollution typically formed when vehicle emissions, industrial processes, and other sources release large amounts of fine particles and gases (such as nitrogen oxides or ground-level ozone) into the air. These pollutants then react in the presence of sunlight to form smog.

However, exposure to high levels of smog can have negative health effects, particularly for people with respiratory conditions such as asthma or chronic obstructive pulmonary disease (COPD). Smog can irritate the eyes, nose, throat, and lungs, causing symptoms such as coughing, wheezing, shortness of breath, and chest pain. Long-term exposure to smog has been linked to more serious health problems, including heart disease, lung cancer, and premature death.

"Wistar rats" are a strain of albino rats that are widely used in laboratory research. They were developed at the Wistar Institute in Philadelphia, USA, and were first introduced in 1906. Wistar rats are outbred, which means that they are genetically diverse and do not have a fixed set of genetic characteristics like inbred strains.

Wistar rats are commonly used as animal models in biomedical research because of their size, ease of handling, and relatively low cost. They are used in a wide range of research areas, including toxicology, pharmacology, nutrition, cancer, cardiovascular disease, and behavioral studies. Wistar rats are also used in safety testing of drugs, medical devices, and other products.

Wistar rats are typically larger than many other rat strains, with males weighing between 500-700 grams and females weighing between 250-350 grams. They have a lifespan of approximately 2-3 years. Wistar rats are also known for their docile and friendly nature, making them easy to handle and work with in the laboratory setting.

I'm sorry for any confusion, but "seasons" is not a term that has a medical definition. Seasons refer to the four divisions of the year (spring, summer, autumn or fall, and winter) based on the position of the earth in its orbit around the sun. If you have any questions related to health or medicine, I'd be happy to try to help answer those!

Sprague-Dawley rats are a strain of albino laboratory rats that are widely used in scientific research. They were first developed by researchers H.H. Sprague and R.C. Dawley in the early 20th century, and have since become one of the most commonly used rat strains in biomedical research due to their relatively large size, ease of handling, and consistent genetic background.

Sprague-Dawley rats are outbred, which means that they are genetically diverse and do not suffer from the same limitations as inbred strains, which can have reduced fertility and increased susceptibility to certain diseases. They are also characterized by their docile nature and low levels of aggression, making them easier to handle and study than some other rat strains.

These rats are used in a wide variety of research areas, including toxicology, pharmacology, nutrition, cancer, and behavioral studies. Because they are genetically diverse, Sprague-Dawley rats can be used to model a range of human diseases and conditions, making them an important tool in the development of new drugs and therapies.

Medical Definition:

"Risk factors" are any attribute, characteristic or exposure of an individual that increases the likelihood of developing a disease or injury. They can be divided into modifiable and non-modifiable risk factors. Modifiable risk factors are those that can be changed through lifestyle choices or medical treatment, while non-modifiable risk factors are inherent traits such as age, gender, or genetic predisposition. Examples of modifiable risk factors include smoking, alcohol consumption, physical inactivity, and unhealthy diet, while non-modifiable risk factors include age, sex, and family history. It is important to note that having a risk factor does not guarantee that a person will develop the disease, but rather indicates an increased susceptibility.

Biological Oxygen Demand (BOD) analysis is a laboratory test used to determine the amount of oxygen consumed by microorganisms during the decomposition of organic matter in a sample of water. It is a measure of the pollution potential of a wastewater, with higher BOD values indicating greater pollution. The test involves measuring the difference in dissolved oxygen (DO) levels between a controlled incubation period (usually five days) and the initial DO level. The difference is reported as the BOD, typically expressed in milligrams per liter (mg/L) or parts per million (ppm). This information helps in assessing the effectiveness of wastewater treatment processes and monitoring water quality in rivers, streams, and other bodies of water.

Medical definitions typically focus on the relevance of a term to medicine or healthcare, so here's a medical perspective on polycyclic compounds:

Polycyclic compounds are organic substances that contain two or more chemical rings in their structure. While not all polycyclic compounds are relevant to medicine, some can have significant medical implications. For instance, polycyclic aromatic hydrocarbons (PAHs) are a type of polycyclic compound that can be found in tobacco smoke and certain types of air pollution. PAHs have been linked to an increased risk of cancer, particularly lung cancer, due to their ability to damage DNA.

Another example is the class of drugs called steroids, which include hormones like cortisol and sex hormones like testosterone and estrogen. These compounds are polycyclic because they contain several interconnected rings in their structure. Steroid medications are used to treat a variety of medical conditions, including inflammation, asthma, and Addison's disease.

In summary, while not all polycyclic compounds are relevant to medicine, some can have important medical implications, either as harmful environmental pollutants or as useful therapeutic agents.

I'm sorry for any confusion, but "industrial waste" is not a term that has a medical definition. Industrial waste is a term used to describe waste produced by industrial activities, such as manufacturing, mining, and construction. It can include a wide variety of materials, including chemicals, metals, soil, and water. Proper management and disposal of industrial waste are important for protecting the environment and public health. If you have any questions related to healthcare or medical terminology, I'd be happy to try to help answer those!

Asthma is a chronic respiratory disease characterized by inflammation and narrowing of the airways, leading to symptoms such as wheezing, coughing, shortness of breath, and chest tightness. The airway obstruction in asthma is usually reversible, either spontaneously or with treatment.

The underlying cause of asthma involves a combination of genetic and environmental factors that result in hypersensitivity of the airways to certain triggers, such as allergens, irritants, viruses, exercise, and emotional stress. When these triggers are encountered, the airways constrict due to smooth muscle spasm, swell due to inflammation, and produce excess mucus, leading to the characteristic symptoms of asthma.

Asthma is typically managed with a combination of medications that include bronchodilators to relax the airway muscles, corticosteroids to reduce inflammation, and leukotriene modifiers or mast cell stabilizers to prevent allergic reactions. Avoiding triggers and monitoring symptoms are also important components of asthma management.

There are several types of asthma, including allergic asthma, non-allergic asthma, exercise-induced asthma, occupational asthma, and nocturnal asthma, each with its own set of triggers and treatment approaches. Proper diagnosis and management of asthma can help prevent exacerbations, improve quality of life, and reduce the risk of long-term complications.

I'm sorry for any confusion, but "Motor Vehicles" is not a term that typically has a medical definition. It is a general term used to describe vehicles that are powered by a motor or engine and are designed for land transportation. This would include cars, trucks, motorcycles, buses, and other similar types of vehicles.

However, in a legal context, a "motor vehicle" may have a specific definition that varies by jurisdiction. For example, in some places, the definition might only include vehicles that are intended for use on public roads, excluding things like golf carts or construction equipment.

If you're looking for a medical term related to motor vehicles, there are many that could apply, such as "motor vehicle accident," "whiplash injury," or "traumatic brain injury due to motor vehicle collision." But the term "motor vehicles" itself does not have a specific medical definition.

'Smoke' is not typically defined in a medical context, but it can be described as a mixture of small particles and gases that are released when something burns. Smoke can be composed of various components including carbon monoxide, particulate matter, volatile organic compounds (VOCs), benzene, toluene, styrene, and polycyclic aromatic hydrocarbons (PAHs). Exposure to smoke can cause a range of health problems, including respiratory symptoms, cardiovascular disease, and cancer.

In the medical field, exposure to smoke is often referred to as "secondhand smoke" or "passive smoking" when someone breathes in smoke from another person's cigarette, cigar, or pipe. This type of exposure can be just as harmful as smoking itself and has been linked to a range of health problems, including respiratory infections, asthma, lung cancer, and heart disease.

Epidemiologic studies are investigations that seek to understand the distribution, patterns, and determinants of health and disease within a population. These studies aim to identify the frequency and occurrence of diseases or health-related events, as well as the factors that contribute to their occurrence. This information is used to develop public health policies and interventions to prevent or control diseases and promote overall health.

There are several types of epidemiologic studies, including:

1. Descriptive studies: These studies describe the characteristics of a population and the distribution of a disease or health-related event within that population. They do not typically investigate causes or risk factors.
2. Analytical studies: These studies examine the relationship between exposures (risk factors) and outcomes (diseases or health-related events). There are two main types of analytical studies: observational studies and experimental studies.
3. Observational studies: In these studies, researchers observe and collect data on a population without intervening or manipulating any variables. There are several types of observational studies, including cohort studies, case-control studies, and cross-sectional studies.
4. Cohort studies: These studies follow a group of people (a cohort) over time to see if they develop a particular disease or health-related event. Researchers collect data on exposures and outcomes at multiple points in time.
5. Case-control studies: These studies compare people with a specific disease or health-related event (cases) to people without the disease or event (controls). Researchers then look back in time to see if there are any differences in exposures between the two groups.
6. Cross-sectional studies: These studies collect data on exposures and outcomes at a single point in time. They are useful for estimating the prevalence of a disease or health-related event, but they cannot establish causality.
7. Experimental studies: In these studies, researchers manipulate variables to see if they have an effect on a particular outcome. The most common type of experimental study is a randomized controlled trial (RCT), in which participants are randomly assigned to receive either the intervention being tested or a control group.

Epidemiologic studies can provide valuable insights into the causes and consequences of diseases and health-related events, as well as potential interventions to prevent or treat them. However, they must be carefully designed and conducted to minimize bias and confounding, and their results should be interpreted with caution.

A "knockout" mouse is a genetically engineered mouse in which one or more genes have been deleted or "knocked out" using molecular biology techniques. This allows researchers to study the function of specific genes and their role in various biological processes, as well as potential associations with human diseases. The mice are generated by introducing targeted DNA modifications into embryonic stem cells, which are then used to create a live animal. Knockout mice have been widely used in biomedical research to investigate gene function, disease mechanisms, and potential therapeutic targets.

I believe there might be a slight confusion in your question. Sulfuric acid is not a medical term, but instead a chemical compound with the formula H2SO4. It's one of the most important industrial chemicals, being a strong mineral acid with numerous applications.

If you are asking for a definition related to human health or medicine, I can tell you that sulfuric acid has no physiological role in humans. Exposure to sulfuric acid can cause irritation and burns to the skin, eyes, and respiratory tract. Prolonged exposure may lead to more severe health issues. However, it is not a term typically used in medical diagnoses or treatments.

Radioactive pollutants are defined as any harmful radioactive substances that are discharged into the environment and pose risks to human health and the ecosystem. These pollutants can be in the form of gases, liquids, or solids and can contaminate air, water, and soil. They originate from various sources such as nuclear power plants, medical facilities, industrial operations, and military activities.

Radioactive pollutants emit ionizing radiation, which can cause damage to living cells and DNA, leading to genetic mutations, cancer, and other health problems. Exposure to high levels of radioactivity can result in acute radiation sickness, including symptoms such as nausea, vomiting, diarrhea, and fever. Long-term exposure to low levels of radiation can increase the risk of developing cancer and other diseases over time.

Radioactive pollutants can also have negative impacts on the environment, contaminating soil and water and reducing biodiversity in affected areas. They can persist in the environment for long periods, making it difficult to clean up and remediate contaminated sites. Therefore, proper management and regulation of radioactive materials are essential to prevent their release into the environment and protect public health and the environment.

'Incineration' is not typically used as a medical term, but it does have relevance to the field of medicine and public health. It generally refers to the process of destroying something, usually waste, through extreme heat and combustion. In the medical context, incineration is often discussed in relation to the disposal of healthcare waste, including infectious materials, sharps, and pharmaceutical products. Proper incineration can help reduce the volume of waste, destroy harmful components, and prevent the spread of infection. However, it's important to note that improper incineration practices can also release toxic emissions into the environment, posing risks to public health.

Fossil fuels are not a medical term, but rather a term used in the field of earth science and energy production. They refer to fuels formed by natural processes such as anaerobic decomposition of buried dead organisms. The age of the organisms and their resulting fossil fuels is typically millions of years, and sometimes even hundreds of millions of years.

There are three main types of fossil fuels: coal, petroleum, and natural gas. Coal is primarily composed of carbon and hydrogen, and it is formed from the remains of plants that lived hundreds of millions of years ago in swamps and peat bogs. Petroleum, also known as crude oil, is a liquid mixture of hydrocarbons and other organic compounds, formed from the remains of marine organisms such as algae and zooplankton. Natural gas is primarily composed of methane and other light hydrocarbons, and it is found in underground reservoirs, often in association with petroleum deposits.

Fossil fuels are a major source of energy for transportation, heating, and electricity generation, but their combustion also releases large amounts of carbon dioxide and other pollutants into the atmosphere, contributing to climate change and air pollution.

Halogenated hydrocarbons are organic compounds containing carbon (C), hydrogen (H), and one or more halogens, such as fluorine (F), chlorine (Cl), bromine (Br), or iodine (I). These compounds are formed when halogens replace one or more hydrogen atoms in a hydrocarbon molecule.

Halogenated hydrocarbons can be further categorized into two groups:

1. Halogenated aliphatic hydrocarbons: These include alkanes, alkenes, and alkynes with halogen atoms replacing hydrogen atoms. Examples include chloroform (trichloromethane, CHCl3), methylene chloride (dichloromethane, CH2Cl2), and trichloroethylene (C2HCl3).
2. Halogenated aromatic hydrocarbons: These consist of aromatic rings, such as benzene, with halogen atoms attached. Examples include chlorobenzene (C6H5Cl), bromobenzene (C6H5Br), and polyhalogenated biphenyls like polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs).

Halogenated hydrocarbons have various industrial applications, including use as solvents, refrigerants, fire extinguishing agents, and intermediates in chemical synthesis. However, some of these compounds can be toxic, environmentally persistent, and bioaccumulative, posing potential health and environmental risks.

The Maximum Allowable Concentration (MAC) is a term used in occupational health to refer to the highest concentration of a hazardous substance (usually in air) that should not cause harmful effects to most workers if they are exposed to it for a typical 8-hour workday, 5 days a week. It's important to note that MAC values are based on average population data and may not protect everyone, particularly those who are sensitive or susceptible to the substance in question.

It's also crucial to differentiate MAC from other similar terms such as the Permissible Exposure Limit (PEL) or Threshold Limit Value (TLV), which are used in different regulatory contexts and may have slightly different definitions and criteria.

Please consult with a certified industrial hygienist, occupational health professional, or other appropriate experts for specific guidance related to hazardous substance exposure limits.

I believe there may be some confusion in your question. "Industry" is a general term that refers to a specific branch of economic activity, or a particular way of producing goods or services. It is not a medical term with a defined meaning within the field of medicine.

However, if you are referring to the term "industrious," which can be used to describe someone who is diligent and hard-working, it could be applied in a medical context to describe a patient's level of engagement and effort in their own care. For example, a patient who is conscientious about taking their medications as prescribed, following through with recommended treatments, and making necessary lifestyle changes to manage their condition might be described as "industrious" by their healthcare provider.

Food contamination is the presence of harmful microorganisms, chemicals, or foreign substances in food or water that can cause illness or injury to individuals who consume it. This can occur at any stage during production, processing, storage, or preparation of food, and can result from various sources such as:

1. Biological contamination: This includes the presence of harmful bacteria, viruses, parasites, or fungi that can cause foodborne illnesses. Examples include Salmonella, E. coli, Listeria, and norovirus.

2. Chemical contamination: This involves the introduction of hazardous chemicals into food, which may occur due to poor handling practices, improper storage, or exposure to environmental pollutants. Common sources of chemical contamination include pesticides, cleaning solvents, heavy metals, and natural toxins produced by certain plants or fungi.

3. Physical contamination: This refers to the presence of foreign objects in food, such as glass, plastic, hair, or insects, which can pose a choking hazard or introduce harmful substances into the body.

Preventing food contamination is crucial for ensuring food safety and protecting public health. Proper hygiene practices, temperature control, separation of raw and cooked foods, and regular inspections are essential measures to minimize the risk of food contamination.

Water pollution is defined medically as the contamination of water sources by harmful or sufficient amounts of foreign substances (pathogens, chemicals, toxic compounds, etc.) which tend to interfere with its normal functioning and can have negative effects on human health. Such pollutants can find their way into water bodies through various means including industrial waste disposal, agricultural runoff, oil spills, sewage and wastewater discharges, and accidental chemical releases, among others.

Exposure to polluted water can lead to a range of health issues, from minor problems like skin irritation or stomach upset, to severe conditions such as neurological disorders, reproductive issues, cancer, and even death in extreme cases. It also poses significant risks to aquatic life, disrupting ecosystems and leading to the decline or extinction of various species. Therefore, maintaining clean and safe water supplies is critical for both human health and environmental preservation.

A cell line that is derived from tumor cells and has been adapted to grow in culture. These cell lines are often used in research to study the characteristics of cancer cells, including their growth patterns, genetic changes, and responses to various treatments. They can be established from many different types of tumors, such as carcinomas, sarcomas, and leukemias. Once established, these cell lines can be grown and maintained indefinitely in the laboratory, allowing researchers to conduct experiments and studies that would not be feasible using primary tumor cells. It is important to note that tumor cell lines may not always accurately represent the behavior of the original tumor, as they can undergo genetic changes during their time in culture.

Volatilization, in the context of pharmacology and medicine, refers to the process by which a substance (usually a medication or drug) transforms into a vapor state at room temperature or upon heating. This change in physical state allows the substance to evaporate and be transferred into the air, potentially leading to inhalation exposure.

In some medical applications, volatilization is used intentionally, such as with essential oils for aromatherapy or topical treatments that utilize a vapor action. However, it can also pose concerns when volatile substances are unintentionally released into the air, potentially leading to indoor air quality issues or exposure risks.

It's important to note that in clinical settings, volatilization is not typically used as a route of administration for medications, as other methods such as oral, intravenous, or inhalation via nebulizers are more common and controlled.

Respiratory disorders are a group of conditions that affect the respiratory system, including the nose, throat (pharynx), windpipe (trachea), bronchi, lungs, and diaphragm. These disorders can make it difficult for a person to breathe normally and may cause symptoms such as coughing, wheezing, shortness of breath, and chest pain.

There are many different types of respiratory disorders, including:

1. Asthma: A chronic inflammatory disease that causes the airways to become narrow and swollen, leading to difficulty breathing.
2. Chronic obstructive pulmonary disease (COPD): A group of lung diseases, including emphysema and chronic bronchitis, that make it hard to breathe.
3. Pneumonia: An infection of the lungs that can cause coughing, chest pain, and difficulty breathing.
4. Lung cancer: A type of cancer that forms in the tissues of the lungs and can cause symptoms such as coughing, chest pain, and shortness of breath.
5. Tuberculosis (TB): A bacterial infection that mainly affects the lungs but can also affect other parts of the body.
6. Sleep apnea: A disorder that causes a person to stop breathing for short periods during sleep.
7. Interstitial lung disease: A group of disorders that cause scarring of the lung tissue, leading to difficulty breathing.
8. Pulmonary fibrosis: A type of interstitial lung disease that causes scarring of the lung tissue and makes it hard to breathe.
9. Pleural effusion: An abnormal accumulation of fluid in the space between the lungs and chest wall.
10. Lung transplantation: A surgical procedure to replace a diseased or failing lung with a healthy one from a donor.

Respiratory disorders can be caused by a variety of factors, including genetics, exposure to environmental pollutants, smoking, and infections. Treatment for respiratory disorders may include medications, oxygen therapy, breathing exercises, and lifestyle changes. In some cases, surgery may be necessary to treat the disorder.

Cell proliferation is the process by which cells increase in number, typically through the process of cell division. In the context of biology and medicine, it refers to the reproduction of cells that makes up living tissue, allowing growth, maintenance, and repair. It involves several stages including the transition from a phase of quiescence (G0 phase) to an active phase (G1 phase), DNA replication in the S phase, and mitosis or M phase, where the cell divides into two daughter cells.

Abnormal or uncontrolled cell proliferation is a characteristic feature of many diseases, including cancer, where deregulated cell cycle control leads to excessive and unregulated growth of cells, forming tumors that can invade surrounding tissues and metastasize to distant sites in the body.

Environmental persistent pharmaceutical pollutants (EPPP) have to be looked at in their entirety of the product chain. ... The term environmental persistent pharmaceutical pollutants (EPPP) was first suggested in the nomination in 2010 of ... 2006) Environmental risk assessment and environmental classification of drugs. In: Environment and Pharmaceuticals. Stockholm: ... However, even at very low environmental concentrations, the chronic exposure to environmental pharmaceuticals chemicals can add ...
The NPRI is also used to inform Canadians of the pollutants in their communities, identify environmental priorities and track ... The National Pollutant Release Inventory (NPRI), established in 1992, and launched in 1993, is the national pollutant release ... The Canadian Environmental Protection Act, 1999 and the National Pollutant Release Inventory. 2. Canada Gazette, Notice with ... "A toxicity-based analysis of Canada's National Pollutant Release Inventory (NPRI): a case study in Nova Scotia". Environmental ...
Scott, Graham R; Sloman, Katherine A (2004). "The effects of environmental pollutants on complex fish behaviour: integrating ... Therefore, there is potential for engaging citizen scientists in environmental research. Pollutants are not always chemicals. ... Pollutant-induced abnormal behaviour refers to the abnormal behaviour induced by pollutants. Chemicals released into the ... while laboratory studies can be used to clarify the mechanisms connecting an environmental pollutant to specific behavioural ...
Convention on Long-Range Transboundary Air Pollution Stockholm Convention on Persistent Organic Pollutants Environmental ... The Aarhus Protocol on Persistent Organic Pollutants, a 1998 protocol on persistent organic pollutants (POPs), is an addition ... "CONVENTION ON ACCESS TO INFORMATION, PUBLIC PARTICIPATION IN DECISION-MAKING AND ACCESS TO JUSTICE IN ENVIRONMENTAL MATTERS" ( ... cite journal}}: Cite journal requires ,journal= (help) "Protocol on Persistent Organic Pollutants (POPs) - Air Pollution - ...
"Environmental pollutants". Previous heroes. University of Birmingham. Retrieved 14 February 2016. "Preventing and resolving ... Life and Environmental Sciences (Biosciences; Geography, Earth and Environmental Sciences; Psychology; Sport and Exercise ... William Bloss and Jamie Lead for their study of pollutants, particularly nanoscale pollutants Paul Jackson, Scott Lucas and ...
Dutch Standards are environmental pollutant reference values (i.e., concentrations in environmental media) used in ... Environmental impact in the Netherlands, Environmental standards, Pollution). ... Barring a few exceptions, the target values are underpinned by an environmental risk analysis wherever possible and apply to ... Groundwater target values provide an indication of the benchmark for environmental quality in the long term, assuming that ...
Environmental Pollutants and Bioavailability. 33 (1): 449-459. doi:10.1080/26395940.2021.2007795. S2CID 245081383. "Olu of ... suffers huge environmental pollution. It is home to a large number of Itsekiris, it is a Suburb of the City of Warri It shares ...
Parke DV (1985). "The role of cytochrome P-450 in the metabolism of pollutants". Environmental Research. 17 (2-4): 97-100. ... With the discovery of PCBs' environmental toxicity, and classification as persistent organic pollutants, their production was ... Environmental Pollutants and Bioavailability. 31 (1): 131-137. doi:10.1080/26395940.2019.1580151. ISSN 2639-5932. Faber H ( ... Persistent organic pollutants under the Convention on Long-Range Transboundary Air Pollution, Persistent organic pollutants ...
"Criteria Air Pollutants". US Environmental Protection Agency. Retrieved 18 August 2021. "Ambient (outdoor) air pollution". ... Uekoetter, F. (2005). "The strange career of the Ringelmann smoke chart". Environmental Monitoring and Assessment. 106 (1-3): ... but to the maximum allowed or recommended concentrations of different pollutants in the air. During 1900-1905, Ringelmann wrote ... such as the World Health Organization's air pollution guidelines and the US Environmental Protection Agency's Air Quality ...
Environment portal Conventional pollutant - U.S. Clean Water Act List of environmental issues Pollutant Standards Index ... Many pollutants are within the following notable groups: Environmental persistent pharmaceutical pollutants (EPPP) Greenhouse ... The damage they cause increases as more pollutant is emitted, and persists as the pollutant accumulates. Stock pollutants can ... Pollutant Release and Transfer Registers (PRTR) are systems to collect and disseminate information on environmental releases ...
These pollutants had an environmental impact. Fisheries were damaged in terms of reduced catches, and in response Chisso ... Fourteen new environmental laws were passed in a single session, giving Japan what at the time were the most stringent ... However, although the environmental protests did result in Japan becoming more democratized, it did not completely rid Japan of ... Chisso knew of the environmental damage caused by its wastewater and was well aware that it was the prime suspect in the ...
... contains environmental persistent pharmaceutical pollutants. Trihalomethanes can also be present as a result of past ... Sewage contains macro-pollutants and micro-pollutants, and may also incorporate some municipal solid waste and pollutants from ... "National Pollutant Discharge Elimination System (NPDES) Permit Writers' Manual" (PDF). United States Environmental Protection ... In the latter case, industrial wastewater may receive pre-treatment at the factories to reduce the pollutant load.: 27 Mixing ...
"How Does Lead Affect Our Environment?". Pollutants and Toxicants: Environmental Lead (Pb). Department of Environmental Quality ... "You Are HereDEQ Pollutants and Toxicants Environmental Lead (Pb)." DEQ - How Does Lead Affect Our Environment?, Agency: ... Environmental Quality, www.michigan.gov/deq/0,4561,7-135-3307_29693_30031-90418--,00.html. "FAQ on RoHS Compliance". RoHS ... Environmental Protection Agency. Milad, George; Gudeczauskas, Don. "Solder Joint Reliability of Gold Surface Finishes (ENIG, ...
Environmental effects of pesticides, Persistent organic pollutants, Pollutants, Pollution). ... Air pollution Aarhus Protocol on Persistent Organic Pollutants Center for International Environmental Law (CIEL) International ... Wania F., Mackay D. (1996). "Tracking the Distribution of Persistent Organic Pollutants". Environmental Science & Technology. ... Harrad, S., "Persistent Organic Pollutants" (2010). Walker, C.H., "Organic Pollutants: An Ecotoxicological Perspective" (2001) ...
... or emerging organic pollutants (EOP), has been receiving increasing attention in the fields of environmental engineering, ... "Antipsychotics as environmental pollutants: An underrated threat?". Science of the Total Environment. 769: 144634. Bibcode: ... "The psychoactive pollutant fluoxetine compromises antipredator behaviour in fish". Environmental Pollution. 222: 592-599. doi: ... An environmental quality standard approach". Integrated Environmental Assessment and Management. 8 (2): 320-330. doi:10.1002/ ...
Antje J Baeumner (12 August 2003). "Biosensors for environmental pollutants and food contaminants". Analytical and ... Baeumner serves as President of the International Association of Environmental Analytical Chemistry. Peter J Asiello; Antje J ...
Brody JG, Moysich KB, Humblet O, Attfield KR, Beehler GP, Rudel RA (June 2007). "Environmental pollutants and breast cancer: ... California Environmental Protection Agency: Air Resources Board, "Proposed Identification of Environmental Tobacco Smoke as a ... 3 in human breast cancer cells". Environmental Health Perspectives. Environmental Health Perspectives, Vol. 105. 105 Suppl 3 ( ... The term "environmental", as used by cancer researchers, means any risk factor that is not genetically inherited. For breast ...
Many environmental pollutants are highly reduced, thus, the oxidation of these pollutants to harmless compounds is ... In: Tarr M. A. (ed.), Chemical Degradation Methods for Wastes and Pollutants; Environmental and Industrial Applications. ... Environmental Protection Agency, Apr. 2001. Tratnyek, Paul G.; B. A. Balko; others (2002). Metals in Environmental Remediation ... U.S. Environmental Protection Agency, EPA/600/R-99/095a. Reeter, C.; Gavaskar, A.; Sass, B.; Gupta, N.; Hicks, J. (1998) ...
Many kinds of pollutants have been proposed, but few have been demonstrated in solving environmental challenges. Cadmium (Cd2+ ... In: Tarr M. A. (ed.), Chemical Degradation Methods for Wastes and Pollutants; Environmental and Industrial Applications. ... "Zero-Valent Iron Nanoparticles for Abatement of Environmental Pollutants: Materials and Engineering Aspects". Critical Reviews ... Environmental Science and Pollution Control, Marcel Dekker, New York, pp 371-421. doi:10.1201/9780203912553.ch9 Fu, Fenglian; ...
Claes Bernes: Persistent organic pollutants. Swedish Environmental Protection Agency, Stockholm 1998. ISBN 91-620-1189-8. ... This causes bioaccumulation and environmental persistence. HpCDD is known to suppress the antibody response of C57B1/6 mice to ... EPA 738-R-95-001 (March 1995) Available from, as of May 18th, 2007 WHO; Environmental Health Criteria 88: Polychlorinated ... 28-34 Global Spin: The Corporate Assault on Environmentalism, Scribe Publications, p. 154 WHO; Environmental Health Criteria 88 ...
Dioxins are a group of chemically related compounds that are persistent environmental pollutants. Dioxins are found throughout ... Tuomisto JT, Asikainen A, Meriläinen P, Haapasaari P (January 2020). "Health effects of nutrients and environmental pollutants ... Claes Bernes: Persistent organic pollutants. Swedish Environmental Protection Agency, Stockholm 1998. ISBN 91-620-1189-8. ... The United States Environmental Protection Agency has categorised dioxin, and the mixture of substances associated with sources ...
Medical and Biological Effects of Environmental Pollutants. Washington DC: National Academies Press. pp. 149-51. doi:10.17226/ ... Environmental Health Perspectives. 121 (7): 818-824. doi:10.1289/ehp.1206245. PMC 3701911. PMID 23694900. Archived from the ...
National Research Council (US) Committee on Medical Biological Effects of Environmental Pollutants (1977). "Biological effects ... Medical and Biological Effects of Environmental Pollutants. Washington DC: National Academies Press. pp. 149-51. doi:10.17226/ ...
Environmental Chemistry: Green Chemistry and Pollutants in Ecosystems. Berlin: Springer. ISBN 978-3-540-22860-8. Mandal, Badal ... The United States' Environmental Protection Agency states that all forms of arsenic are a serious risk to human health. The ... The Department of Environmental Protection for New Jersey set a drinking water limit of 5 ppb in 2006. The IDLH (immediately ... Civil and Environmental Engineering. University of Maine Zeng Zhaohua, Zhang Zhiliang (2002). "The formation of As element in ...
"Disruption of Thyroid Hormone Function by Environmental Pollutants". Journal of Health Science. 55 (2): 147-160. doi:10.1248/ ... Tsai WT (2006). "Human health risk on environmental exposure to Bisphenol-A: a review". Journal of Environmental Science and ... Environmental Health Perspectives. National Institute of Environmental Health Sciences. 123 (7): 643-50. doi:10.1289/ehp. ... The U.S. Environmental Protection Agency (EPA) also holds the position that BPA is not a health concern. In 2011, Andrew Wadge ...
Environmental insults and pollutants also affect SFTPA2 expression. Exposure of lung cells to particulate matter affects ... Pollutants and viral infections also affect SFTPA2 translation mechanisms (see eukaryotic translation, translation (biology)). ... Its expression is also regulated by epigenetic and environmental factors. Differences in the SFTPA2 gene sequence at the coding ... Environmental insults such as air pollution, and exposure to high concentrations of ozone and particulate matter can affect SP- ...
Environmental Toxicology: Biological and Health Effects of Pollutants. CRC Press. ISBN 1-56670-670-X. National Pollutant ... Lead is now a common environmental pollutant. For the birds, a commons source is lead shot, eaten as grit. Those routes include ... Lightfoot, T.; Yeager, J. (May 2008). "Pet bird toxicity and related environmental concerns". The Veterinary Clinics of North ... ISBN 0-7817-3770-2. Grant, L.D. (2009). "Lead and compounds". In Lippmann, M. (ed.). Environmental Toxicants: Human Exposures ...
Cats may be particularly sensitive to environmental pollutants. Cats can succumb quickly from ethylene glycol poisoning, after ... Williams, R. T. (1 February 1978). "Species Variations in the Pathways of Drug Metabolism". Environmental Health Perspectives. ... Potera, C. (2007). "Chemical Exposures: Cats as Sentinel Species". Environmental Health Perspectives. 115 (12): A580. doi: ...
Environmental insults and pollutants also affect SFTPA1 expression. Exposure of lung cells to particulate matter affects ... Pollutants and viral infections also affect SFTPA1 translation mechanisms (see eukaryotic translation, translation (biology)). ... Its expression is also regulated by epigenetic and environmental factors. Differences in the SFTPA1 gene sequence at the coding ... Environmental insults such as air pollution, and exposure to high concentrations of ozone and particulate matter can affect SP- ...
"Traffic Exhaust Pollutants". Environmental Health Investigations Branch, California Department of Public Health. Archived from ... Car pollutants include carbon monoxide, nitrogen oxides, particulate matter (fine dusts and soot), and toxic air pollutants ... air pollutant levels were measured for mothers who had children with autism and then compared to air pollutant levels in ... which is a source of toxic vehicle pollutants. Previous studies have found correlations between exposure to vehicle pollutants ...
  • The U.S. Public Interest Research Group and Sierra Club filed a 60-day notice of their intent to sue the Environmental Protection Agency today for failing to meet a July 1, 2003 deadline to propose regulations to reduce emissions of toxic chemicals such as benzene and formaldehyde from the nation's cars, trucks, and buses. (earthjustice.org)
  • EPA's own National-Scale Air Toxics Assessment shows that motor vehicle emissions are the largest source of hazardous air pollutants nationwide, and that these pollutants substantially increase the risks of cancer and other serious adverse health effects for millions of Americans. (earthjustice.org)
  • For years, the EPA has promised the public and the courts that it will reduce toxic emissions from motor vehicles - just not yet," said Jim Pew, attorney for Earthjustice, who is representing the environmental groups in the case. (earthjustice.org)
  • The agency committed to implement a "Technical Analysis Plan" to obtain the missing information and then to issue a proposed rule to reduce emissions of hazardous air pollutants from motor vehicles by July 1, 2003, taking final action by July 1, 2004. (earthjustice.org)
  • The goal of the issue is to present advances in molecular-level study of atmospheric chemical processes that form our critical understanding of pollutant emissions, transport, transformation, and deposition. (rsc.org)
  • Began supporting government efforts in Brazil, Chile and Mexico to create plans and programs to decrease emissions of short-live climate pollutants. (aida-americas.org)
  • This study aimed to estimate hazardous and greenhouse gas (GHG) emissions and associated environmental impacts from fuelwood burning and synthetic fertilizer application by tobacco growers in Pakistan during the cropping year of 2014-2015. (who.int)
  • EPA's latest rulemaking regulating Hazardous Air Pollutant ("HAP") emissions from coal- and oil-fired electric utility steam generating units ("EGUs") is unlikely to be an exception. (elnonline.com)
  • The emission figures are from the national air pollutant emission inventtories and are based on Finland's official annual reports to the UN ECE Long-Range Transboundary Air Pollution Convention (CLRTAP) and the EU ENational Emissions Ceilings Directive (NECD). (ymparisto.fi)
  • Finnish Environment Institute (Syke) maintains air pollutant emission inventories and acts as the National Inventory Agency in reporting under the UN ECE Long-Range Transboundary Air Pollution Convention (CLRTAP) and the EU National Emissions Ceilings Directive (NECD). (ymparisto.fi)
  • Air pollutant emissions are acidifying compounds, particles, volatile and persistent organic compounds and heavy metals. (ymparisto.fi)
  • The legend is scaled according to the total emissions of the specific pollutant, thus the absolute emission levels vary from those of acidifying substances and particles (kilotons) to those of heavy metals and persistent organic compounds (tons, kilograms or grams). (ymparisto.fi)
  • The operators have obligations in the environmental permits to report on emissions to the authorities. (ymparisto.fi)
  • Emissions from those plants that have obligations to report emissions in their environmental permits can be searched in EEA's E-PRTR service. (ymparisto.fi)
  • Emissions can be searched by pollutant, year and emission source. (ymparisto.fi)
  • Inadequate ventilation can increase indoor pollutant levels by not bringing in enough outdoor air to dilute emissions from indoor sources and by not carrying indoor air pollutants out of the home. (phoslab.com)
  • The term environmental persistent pharmaceutical pollutants (EPPP) was first suggested in the nomination in 2010 of pharmaceuticals and environment as an emerging issue in a Strategic Approach to International Chemicals Management (SAICM) by the International Society of Doctors for the Environment (ISDE). (wikipedia.org)
  • Objective Relationships were examined between persistent organic pollutants (POPs) and incident type 2 diabetes, end-stage renal disease (ESRD) and mortality. (bmj.com)
  • A growing body of evidence suggests that environmental pollutants, such as heavy metals, persistent organic pollutants and plasticizers play an important role in the development of chronic diseases. (nih.gov)
  • Persistent organic pollutants ( POPs ) are organic compounds that are resistant to degradation through chemical , biological , and photolytic processes. (wikipedia.org)
  • The effect of POPs on human and environmental health was discussed, with intention to eliminate or severely restrict their production, by the international community at the Stockholm Convention on Persistent Organic Pollutants in 2001. (wikipedia.org)
  • [3] Compounds that make up POPs are also classed as PBTs (persistent, bioaccumulative and toxic) or TOMPs (toxic organic micro pollutants). (wikipedia.org)
  • However, even at very low environmental concentrations, the chronic exposure to environmental pharmaceuticals chemicals can add to the effects of other chemicals in the cocktail is still not studied. (wikipedia.org)
  • Using the regression coefficients (weights) from joint analyses of the combined data and exposure concentrations, ERS were computed as a weighted sum of the pollutant levels. (nih.gov)
  • Governments and regulatory agencies set limits on pollutant concentrations to protect the environment and human health. (alliedacademies.org)
  • Electrochemical techniques like Voltammetry and Potentiostat/Galvanostat are used to measure pollutant concentrations based on their electrochemical properties. (alliedacademies.org)
  • Some pollutants exist in very low concentrations, making their detection and quantification difficult. (alliedacademies.org)
  • areas that do not meet the NAAQS are called nonattainment areas and must develop comprehensive state plans to reduce pollutant concentrations to a safe level. (utah.gov)
  • Combining modeled ambient air concentrations with data from a large prospective cohort of California women with over 15 years of follow-up, we examined the relationship between breast cancer incidence and modeled concentrations of air pollutants shown to be mammary gland carcinogens (MGCs). (biomedcentral.com)
  • Modeled annual average ambient air concentrations of 24 MGCs from the U.S. Environmental Protection Agency were linked to participants' addresses. (biomedcentral.com)
  • Impacts of air pollution to the environment are monitored through measuring emission deposits and environmental concentrations. (ymparisto.fi)
  • Associations between socioeconomic status and environmental toxicant concentrations in adults in the USA: NHANES 2001-2010. (aurametrix.com)
  • High temperature and humidity levels can also increase concentrations of some pollutants. (phoslab.com)
  • Motor vehicles also produce more than one million tons of other hazardous air pollutants. (earthjustice.org)
  • Natural News) Scientists found that some face masks used by the general public are laced with toxic chemicals, including known carcinogens and environmental pollutants. (naturalnews.com)
  • 1980. Bioconcentration and elimination of selected water pollutants by bluegill sunfish (Lepomis mucrochirus). (cdc.gov)
  • Determination of IAQ involves the collection of air samples, monitoring human exposure to pollutants, collection of samples on building surfaces and computer modelling of air flow inside buildings. (phoslab.com)
  • For children, the fact is due to greater exposure to pollutants, increased ventilation per minute and higher levels of physical activity 13 . (bvsalud.org)
  • Inamuddin , " Bioremediation for Environmental Pollutants ", Bentham Science Publishers (2023). (benthamscience.com)
  • Bioremediation is a new technique that employs living organisms, usually bacteria and fungi, to remove pollutants from soil and water, preferably in situ. (benthambooks.com)
  • Bioremediation for Environmental Pollutants discusses the latest research in green chemistry and practices and principles involved in the quality improvement of water by remediation. (benthambooks.com)
  • It covers different aspects of environmental problems and their remedies with up-to-date developments in the field of bioremediation of industrial/environmental pollutants. (benthambooks.com)
  • It elaborates on the application of microbial enzymes, microalgae, and genetically engineered microorganisms in the bioremediation of significant pollutants, food wastes, distillery wastewater, and pharmaceutical wastes. (benthambooks.com)
  • The WG2 is related to bioremediation and surface science using BESs, leading to environmental sustainability. (cost-phoenix.eu)
  • This study suggests ERS is a promising tool for characterizing disease risk from multi-pollutant exposures. (nih.gov)
  • Studies suggest that higher breast cancer rates in urban areas persist after accounting for the prevalence of known risk factors, leading to speculation that urban environmental exposures, such as air pollution, may play a role in the etiology of breast cancer. (biomedcentral.com)
  • About 30% of human diseases are due to environmental exposures as genetics is not the whole story. (aurametrix.com)
  • The Agency for Toxic Substances and Disease Registry (ATSDR) is releasing for public comment a health consultation describing public health implications of exposures to hydrogen sulfide and National Ambient Air Quality Standard (NAAQS) pollutants. (cdc.gov)
  • Cadmium (Cd) is a widespread environmental and occupational pollutant that has emerged as a major cause of pathobiochemical events and damage in a number of organs. (coconutoil.com)
  • Textbook of clinical occupational and environmental medicine / [edited by] Linda Rosenstock, Mark R. Cullen. (who.int)
  • Quantitative risk assessment for environmental and occupational health / W. H. Hallenbeck and K. M. Cunningham. (who.int)
  • The presence of heavy metals, dyes, fluorides, dissolved solids, and many other pollutants used in industry and agriculture are responsible for hazardous levels of water pollution. (benthambooks.com)
  • Many chemicals and pollutants are naturally present in the environment, while other chemicals are created by humans for use in consumer, or everyday, products. (healthvermont.org)
  • Here you will find information on natural and human-made chemicals and pollutants found in the air, water, soil and consumer products. (healthvermont.org)
  • OK Environmental Chemicals and Type 2 Diabetes. (aurametrix.com)
  • However,quality of drinking water is the affected by the presence of several environmentalpollutants, including endocrine disrupting chemicals (EDCs), pharmaceuticalsand personal care products (PPCPs), and other substances (Padhye et al. (niagarafallshypnosiscenter.com)
  • Twenty years later Congress passed the Clean Air Act Amendments of 1990 , which increased the Environmental Protection Agency's authority to reduce the pollution responsible for acid rain, airborne toxics, hazardous pollutants, ozone-depleting chemicals, and more smog-forming pollutants. (americanprogress.org)
  • Intensive agriculture, industrialization, and consumerism have resulted in the degradation of environmental quality. (benthamscience.com)
  • Due to this capacity for long-range transport, POP environmental contamination is extensive, even in areas where POPs have never been used, and will remain in these environments years after restrictions implemented due to their resistance to degradation. (wikipedia.org)
  • POPs enter the gas phase under certain environmental temperatures and volatilize from soils , vegetation , and bodies of water into the atmosphere , resisting breakdown reactions in the air, to travel long distances before being re-deposited. (wikipedia.org)
  • The new Toxics Release Inventory (TRI) data submitted to the EPA by TVA also show that the Kingston ash spill deposited nearly 320 tons of vanadium in the Emory River, or more than seven times the total discharge of this toxic pollutant from all power plants in 2007. (environmentalintegrity.org)
  • The 2.66 million pound of toxic pollutants dumped into the Emory River in 2008 is nearly 45 times higher than the 59,950 pounds of such materials the TVA Kingston coal plant reported that it released into all U.S. waterways in 2007. (environmentalintegrity.org)
  • These toxic pollutants are hazardous to the health of humans, fish and other aquatic life. (environmentalintegrity.org)
  • The National Pollutant Inventory (NPI) is Australia's most comprehensive repository of information about toxic pollution. (archive.org.au)
  • The air monitoring data that are available for the Midlothian area will support public health evaluations for many of the pollutants of concern, the Agency for Toxic Substances and Disease Registry (ATSDR) concludes in the health consultation released today for public comment. (cdc.gov)
  • The United States Environmental Protection Agency (EPA) has established National Ambient Air Quality Standards (NAAQS) for each of these pollutants. (utah.gov)
  • Many environmental pollutants can find their way into the food chain and water supply, potentially posing health risks to humans. (alliedacademies.org)
  • Such a network should facilitate the production of good quality data on emerging substances which are comparable across Europe, thus providing the basis for further identification of newly emerging pollutants and assessment of their potential risks to humans and ecosystems. (eugris.info)
  • They are commonly used for analyzing organic pollutants such as pesticides and volatile organic compounds (VOCs). (alliedacademies.org)
  • Most epidemiologic studies have examined environmental pollutants individually, but in real life, we are exposed to multi-pollutants and pollution mixtures, not single pollutants. (nih.gov)
  • Identifying the source of pollutants is critical for effective pollution control and remediation. (alliedacademies.org)
  • The Ninth Circuit panel held that the wells were required to obtain National Pollutant Discharge Elimination System ("NPDES") permit coverage because the discharge from the wells was "fairly traceable" from the discharge point (point source) to a navigable water. (stoelrivesenvironmentallawblog.com)
  • The data of ambient levels of particulate matter, sulfur dioxideand ozone were obtained from the Company of Technology of Environmental Sanitation (CETESB) and temperature and humidity from the Foundation for Science, Technology and Space Applications (FUNCATE). (bvsalud.org)
  • It is known that the lungs are the main target of attack of air pollutants, among which the primary are particulate matter (PM 10 ), sulfur dioxide (SO 2 ) and ozone (O 3 ). (bvsalud.org)
  • Indoor reactions are initiated mainly by ozone, a pollutant, which is transported from the outdoor environment into the indoor environment by building ventilation. (cdc.gov)
  • Explore the interconnections between pollution, climate change, and their implications for public health and Environmental Health. (reed.co.uk)
  • These warnings heighten the necessity of reducing carbon and the other pollutants responsible for climate change. (americanprogress.org)
  • 2009). Exposure of pollutants like BPA and other EDCs can also cause variations in behavior of fishesin which includes reduction the capability for avoidance from predators, reducing/eliminating the ability to detect chemical alarm substances released by conspecifics,affecting schooling behavior, influencing feeding behavior, and may changesocial hierarchies within a group (Scott and Sloman, 2004). (niagarafallshypnosiscenter.com)
  • The pollutants released include benzene, toluene, ethylbenzene and xylenes (BTEX), which are significant due to their high level of toxicity. (who.int)
  • Due to poor ventilation and high exposure duration, the average benzene concentration over the sampling campaign exceeded the US Environmental Protection Agency's chronic inhalation exposure reference concentration. (who.int)
  • Among these, microbes have emerged as one of the potential indicators of environmental pollution, as they are more sensitive to trace levels of pollutants than plants/ animals/other organisms. (benthamscience.com)
  • Chemical analysis can trace pollutants back to their origins. (alliedacademies.org)
  • M. Fernando R. Pereira 2004-10-01 00:00:00 Nowadays trace organic pollutants represent a major concern in water treatment systems. (deepdyve.com)
  • Nowadays trace organic pollutants represent a major concern in water treatment systems. (deepdyve.com)
  • Results of search for 'su:{Environmental pollutants. (who.int)
  • Various pollutants, whether they are from industrial processes, agricultural activities, or other sources, can have detrimental effects on ecosystems and human health [ 1 ]. (alliedacademies.org)
  • Natural News) Air pollution is an increasingly global problem as more and more industries produce massive amounts of pollutants that bring detrimental effects on air quality and ecosystems. (naturalnews.com)
  • Specifically, CBD claims that the federal government violated the Outer Continental Shelf Lands Act, the National Environmental Policy Act, and the Coastal Zone Management Act "without analyzing fracking pollution's threats to ocean ecosystems, coastal communities and marine wildlife, including sea otters, fish, sea turtles and whales. (stoelrivesenvironmentallawblog.com)
  • Discover the complexities of air and water pollution and their associated health risks in the context of Environmental Health. (reed.co.uk)
  • To mitigate these risks, it is crucial to monitor and analyze environmental pollutants rigorously. (alliedacademies.org)
  • Environmental risk refers to the risk of toxicity to the aquatic environment. (wikipedia.org)
  • Its subsequent disposal in waterways causes harmful effects on aquatic organisms, environmental microcosms, and associated living organisms. (newsindiaplus.com)
  • In Sweden, the industry together with universities and health care sector has developed a method for environmental risk assessment and environmental classification of drugs. (wikipedia.org)
  • We take on many of the biggest environmental and health challenges of our time and stick with them. (earthjustice.org)
  • The study, published in the journal Sleep Health , is among the first to examine multiple environmental variables in the bedroom and their associations with sleep efficiency, which is the time spent sleeping relative to the time available for sleep. (earth.com)
  • Department of Environmental Health Sciences, University of Michigan School of Public Health, Ann Arbor, Michigan, United States of America. (nih.gov)
  • Although multi-pollutant approaches have been recognized recently, challenges exist such as how to estimate the risk of adverse health responses from multi-pollutants. (nih.gov)
  • We examined 134 environmental pollutants in relation to serum lipids (total cholesterol, high-density lipoprotein cholesterol (HDL), low-density lipoprotein cholesterol (LDL) and triglycerides) using data from the National Health and Nutrition Examination Survey between 1999 and 2006. (nih.gov)
  • We'll learn about the different types of waste and pollutants and how they impact our environment and our health. (reed.co.uk)
  • This course is a great way to learn about the importance of environmental health, and how we can all make a difference in protecting our planet. (reed.co.uk)
  • Develop a comprehensive understanding of environmental health principles and their significance in promoting Environmental Health. (reed.co.uk)
  • Gain insights into the causes and effects of waste, pollution, and pollutants on our environment and Environmental Health. (reed.co.uk)
  • Learn effective strategies for recovering resources and managing waste sustainably to protect Environmental Health. (reed.co.uk)
  • Understand the impact of food waste and plastic pollution on Environmental Health and sustainable practices. (reed.co.uk)
  • Environmental health is the study of the relationship between the environment and human health. (reed.co.uk)
  • This course will provide you with an overview of environmental health. (reed.co.uk)
  • You will learn about the different types of environmental pollutants, how they impact human health, and what you can do to reduce your exposure to them. (reed.co.uk)
  • Discover a world of environmental health and make a difference. (reed.co.uk)
  • Upon completing the course, you can obtain a certificate titled Environmental Health . (reed.co.uk)
  • Public health professionals seeking to expand their knowledge of environmental health. (reed.co.uk)
  • Students pursuing studies in environmental science, public health, or related fields. (reed.co.uk)
  • To estimate long-term exposure to traffic-related air pollutants on an individual basis and to assess adverse health effects using a combination of air pollution measurement data, data from geographical information systems (GIS) and questionnaire data. (bmj.com)
  • The Clean Air Act identifies six common air pollutants that are found all over the United States and can injure health, harm the environment or cause property damage. (utah.gov)
  • As adults, our health can be influenced by a range of lifestyle and environmental factors, increasing the risk for developing a series of non-communicable diseases such as type 2 diabetes, heart disease and obesity. (mdpi.com)
  • Supported by epidemiological data and experimental studies, specific mechanisms have been defined linking environmental perturbations, disrupted fetal and neonatal development and adult ill-health. (mdpi.com)
  • Among the environmental factors related to the pathogenesis of respiratory diseases, we can highlight air pollution, a major public health problems today. (bvsalud.org)
  • Studies have found that air pollutants, even at exposure levels below acceptable standards, can cause deleterious effects to human health 1 . (bvsalud.org)
  • Diesel fuel is known to emit pollutants that have a negative impact on environmental and human health. (who.int)
  • It has been estimated that indoor environmental quality-related health issues cost businesses in the range of $20-70 billion annually due to lost productivity, decreased performance, and sick absences. (cdc.gov)
  • Scientists in china have developed a passive air sampler that can be used for monitoring common indoor air pollutants. (phoslab.com)
  • The points above very briefly highlight some of the issues related to indoor environmental quality. (cdc.gov)
  • Developed an informative brief (in Spanish) for leaders at COP19 explaining SLCPs, the main pollutants in this category and the reasons to regulate and reduce their emission. (aida-americas.org)
  • The air pollutant emission inventory is carried out according to the Guidebook by the EMEP and the European Environment Agency. (ymparisto.fi)
  • When polluted storm water flows from a concrete-lined river channel to an unlined portion of the same river, does that movement of water constitute a "discharge of pollutants" under the Clean Water Act? (stoelrivesenvironmentallawblog.com)
  • The researchers also showed that they could turn Arabidopsis thaliana plants into chemical sensors by delivering carbon nanotubes that detect the gas nitric oxide, an environmental pollutant produced by combustion. (science20.com)
  • By augmenting them with nanomaterials, plants could enhance their energy production and get completely new functions, such as monitoring environmental pollutants. (science20.com)
  • Reports filed with the Environmental Protection Agency (EPA) by the Tennessee Valley Authority (TVA) show that the TVA's Kingston coal plant dumped into the Emory River in 2008 an estimated 140,000 pounds of arsenic contained in coal ash - more than twice the reported amount of the toxin discharged into U.S. waterways from all U.S. power plants in 2007. (environmentalintegrity.org)
  • The Clean Air Act allows the Environmental Protection Agency to limit air pollutants from stationary sources such as chemical plants, utilities, and industrial plants, as well as automobiles and other mobile sources. (americanprogress.org)
  • Adjusted odds ratios (ORs) for wheezing, cough without infection, dry cough at night, bronchial asthma, bronchitis and respiratory infections indicated positive associations with traffic-related air pollutants. (bmj.com)
  • Among respiratory diseases, bronchial asthma, one of the most common chronic diseases of childhood, has been linked to exposure to environmental pollutants in many parts of the world 3-6 . (bvsalud.org)
  • In Brazil, the relationship between exposure to environmental pollutants and respiratory disease has been studied mainly in large urban centers and medium-size cities 1,7-10 . (bvsalud.org)
  • The occurring problems from EPPPs are in parallel explained under environmental impact of pharmaceuticals and personal care products (PPCP). (wikipedia.org)
  • Environmental enthusiasts committed to making a positive impact on our planet. (reed.co.uk)
  • Analyzing pollutants helps assess the environmental impact of human activities. (alliedacademies.org)
  • Current studies focus on regional influenza and the impact of environmental pollutants on time series , and lack of overall studies on the national influenza epidemic and the nonlinear correlation between environmental pollutants and influenza . (bvsalud.org)
  • Spatio-temporal evolution patterns of influenza incidence and its nonlinear spatial correlation with environmental pollutants in China. (bvsalud.org)
  • This study used Chinese influenza incidence data for 2007-2017 released by the China CDC and air pollutant site monitoring data. (bvsalud.org)
  • Then, based on the spatial heterogeneity of influenza incidence in China , Generalized additive model (GAM) was used to identify the correlation effect of environmental pollutants (PM2.5, PM10, CO, SO2, NO2, O3) and influenza incidence . (bvsalud.org)
  • The correlation between environmental pollutants and influenza incidence was nonlinear. (bvsalud.org)
  • Relevant departments should improve the monitoring of influenza epidemic , optimize the allocation of resources , reduce environmental pollution , and strengthen vaccination to effectively prevent the aggravation and spread of influenza epidemic in the high incidence season and areas. (bvsalud.org)
  • Environmental pollution has become a serious issue of concern across the world. (benthamscience.com)
  • Sufficient information exists to warrant concern about exposure of sensitive persons to multiple air pollutants, especially in the past while they were exercising and when sulfur dioxide levels were higher. (cdc.gov)
  • This book is invaluable for researchers and scientists in environmental science, environmental microbiology, and waste management. (benthambooks.com)
  • The main themes are a safe living environment, the preservation of biodiversity and the prevention of environmental damage. (ymparisto.fi)
  • Although the contributions of ERS to overall risk predictions for lipid outcomes were modest, we found relatively stronger associations between ERS and lipid outcomes than with individual pollutants. (nih.gov)
  • After controlling for individual confounders, significant associations were found between the pollutant PM 2.5 and sneezing, runny/stuffed nose during the first year of life (OR 1.16, 95% confidence interval 1.01 to 1.34) Similar effects were observed for the second year of life. (bmj.com)
  • It is based on the ratio between predicted environmental concentration of the substance (PEC) and the highest concentration of the substance that does not have a harmful effect in the environment (PNEC). (wikipedia.org)
  • Is it because heavier breathing helps us to getting rid of the pollutants before they had a chance to trigger harmful effects? (aurametrix.com)
  • ATSDR found that harmful effects are possible for certain air pollutants in the past. (cdc.gov)
  • ATSDR found that certain air pollutants may have caused harmful effects in both the past and present. (cdc.gov)
  • Although banned since 1979 due to their environmental and human toxicity, PCBs can still be found at measurable levels in the environment and in human tissues and plasma. (bakeryandsnacks.com)
  • Using a two-stage approach, stage-1 for discovery (n = 10818) and stage-2 for validation (n = 4615), we identified 13 associated pollutants for total cholesterol, 9 for HDL, 5 for LDL and 27 for triglycerides with adjustment for sociodemographic factors, body mass index and serum nutrient levels. (nih.gov)
  • The small entity electromagnetic field effects may intensify the effects of other agents such as environmental pollutants. (cnr.it)
  • It is believed that the manifestations of the biological effects of air pollution have a behavior gap in relation to the individual's exposure to these pollutants 14 . (bvsalud.org)
  • We propose an "Environmental Risk Score (ERS)" as a new simple tool to examine the risk of exposure to multi-pollutants in epidemiologic research. (nih.gov)
  • This is of great importance from the safety point of view (risk evaluation), because electromagnetic fields exposure of general population is often combined with other environmental pollutants. (cnr.it)
  • Natural News) Diet, genetics and environmental factors all have a hand in determining one's risk for cancer, one of the deadliest chronic diseases around the globe. (naturalnews.com)
  • But a recent report from an environmental advocacy group cautions that millions across the US could be facing a greater risk of cancer due to contaminated tap water. (naturalnews.com)
  • SP2: INTERACTION - Allow an EU-wide exchange of information Via international workshops NORMAN will foster co-operation and the exchange of information within the community responsible for carrying out monitoring (reference laboratories, monitoring institutes and related organisations) and between this community and bodies requesting and specifying monitoring, including those responsible for risk assessment, risk management, substance prioritisation and the setting of environmental quality standards. (eugris.info)
  • Our results confirmed the etiology of the ocular infection, implicating snail vectors as environmental risk factors for ocular parasitosis. (cdc.gov)
  • Overall, we think that asthma is about 50%-60% genetic, meaning that there are both genetic and environmental determinants and risk factors. (medscape.com)