Benzene
Benzene Derivatives
Hydroquinones
Xylenes
Occupational Exposure
Petroleum
Air Pollutants, Occupational
Maximum Allowable Concentration
Hydrocarbons, Aromatic
Biodegradation, Environmental
Environmental Monitoring
Hydrocarbons
Chemical Industry
Chlorobenzenes
Methodological issues in biomonitoring of low level exposure to benzene. (1/773)
Data from a pilot study on unmetabolized benzene and trans,trans muconic acid (t,t-MA) excretion in filling station attendants and unexposed controls were used to afford methodological issues in the biomonitoring of low benzene exposures (around 0.1 ppm). Urinary concentrations of benzene and t,t-MA were measured by dynamic head-space capillary GC/FID and HPLC, respectively. The accuracy of the HPLC determination of t,t-MA was assessed in terms of inter- and intra-method reliability. The adequacy of urinary t,t-MA and benzene as biological markers of low benzene exposure was evaluated by analysing the relationship between personal exposure to benzene and biomarker excretion. Filling station attendants excreted significantly higher amounts of benzene, but not of t,t-MA, than controls. Adjusting for occupational benzene exposure, smokers excreted significantly higher amounts of t,t-MA, but not of unmetabolized benzene, than nonsmokers. A comparative analysis of the present and previously published biomonitoring surveys showed a good inter-study agreement regarding the amount of t,t-MA and unmetabolized benzene excreted (about 0.1-0.2 mg/l and 1-2 micrograms/l, respectively) per unit of exposure (0.1 ppm). For each biomarker, based on the distribution of parameters observed in the pilot study, we calculated the minimum sample size required to estimate the population mean with given confidence and precision. (+info)The alkene monooxygenase from Xanthobacter strain Py2 is closely related to aromatic monooxygenases and catalyzes aromatic monohydroxylation of benzene, toluene, and phenol. (2/773)
The genes encoding the six polypeptide components of the alkene monooxygenase from Xanthobacter strain Py2 (Xamo) have been located on a 4.9-kb fragment of chromosomal DNA previously cloned in cosmid pNY2. Sequencing and analysis of the predicted amino acid sequences indicate that the components of Xamo are homologous to those of the aromatic monooxygenases, toluene 2-, 3-, and 4-monooxygenase and benzene monooxygenase, and that the gene order is identical. The genes and predicted polypeptides are aamA, encoding the 497-residue oxygenase alpha-subunit (XamoA); aamB, encoding the 88-residue oxygenase gamma-subunit (XamoB); aamC, encoding the 122-residue ferredoxin (XamoC); aamD, encoding the 101-residue coupling or effector protein (XamoD); aamE, encoding the 341-residue oxygenase beta-subunit (XamoE); and aamF, encoding the 327-residue reductase (XamoF). A sequence with >60% concurrence with the consensus sequence of sigma54 (RpoN)-dependent promoters was identified upstream of the aamA gene. Detailed comparison of XamoA with the oxygenase alpha-subunits from aromatic monooxygenases, phenol hydroxylases, methane monooxygenase, and the alkene monooxygenase from Rhodococcus rhodochrous B276 showed that, despite the overall similarity to the aromatic monooxygenases, XamoA has some distinctive characteristics of the oxygenases which oxidize aliphatic, and particularly alkene, substrates. On the basis of the similarity between Xamo and the aromatic monooxygenases, Xanthobacter strain Py2 was tested and shown to oxidize benzene, toluene, and phenol, while the alkene monooxygenase-negative mutants NZ1 and NZ2 did not. Benzene was oxidized to phenol, which accumulated transiently before being further oxidized. Toluene was oxidized to a mixture of o-, m-, and p-cresols (39.8, 18, and 41.7%, respectively) and a small amount (0.5%) of benzyl alcohol, none of which were further oxidized. In growth studies Xanthobacter strain Py2 was found to grow on phenol and catechol but not on benzene or toluene; growth on phenol required a functional alkene monooxygenase. However, there is no evidence of genes encoding steps in the metabolism of catechol in the vicinity of the aam gene cluster. This suggests that the inducer specificity of the alkene monooxygenase may have evolved to benefit from the naturally broad substrate specificity of this class of monooxygenase and the ability of the host strain to grow on catechol. (+info)Benzene-induced uncoupling of naphthalene dioxygenase activity and enzyme inactivation by production of hydrogen peroxide. (3/773)
Naphthalene dioxygenase (NDO) is a multicomponent enzyme system that oxidizes naphthalene to (+)-cis-(1R,2S)-1,2-dihydroxy-1, 2-dihydronaphthalene with consumption of O2 and two electrons from NAD(P)H. In the presence of benzene, NADH oxidation and O2 utilization were partially uncoupled from substrate oxidation. Approximately 40 to 50% of the consumed O2 was detected as hydrogen peroxide. The rate of benzene-dependent O2 consumption decreased with time, but it was partially increased by the addition of catalase in the course of the O2 consumption by NDO. Detailed experiments showed that the total amount of O2 consumed and the rate of benzene-induced O2 consumption increased in the presence of hydrogen peroxide-scavenging agents, and further addition of the terminal oxygenase component (ISPNAP) of NDO. Kinetic studies showed that ISPNAP was irreversibly inactivated in the reaction that contained benzene, but the inactivation was relieved to a high degree in the presence of catalase and partially relieved in the presence of 0.1 mM ferrous ion. Benzene- and naphthalene-reacted ISPNAP gave almost identical visible absorption spectra. In addition, hydrogen peroxide added at a range of 0.1 to 0.6 mM to the reaction mixtures inactivated the reduced ISPNAP containing mononuclear iron. These results show that hydrogen peroxide released during the uncoupling reaction acts both as an inhibitor of benzene-dependent O2 consumption and as an inactivator of ISPNAP. It is proposed that the irreversible inactivation of ISPNAP occurs by a Fenton-type reaction which forms a strong oxidizing agent, hydroxyl radicals (. OH), from the reaction of hydrogen peroxide with ferrous mononuclear iron at the active site. Furthermore, when [14C]benzene was used as the substrate, cis-benzene 1,2-dihydrodiol formed by NDO was detected. This result shows that NDO also couples a trace amount of benzene to both O2 consumption and NADH oxidation. (+info)Adenosylcobalamin-mediated methyl transfer by toluate cis-dihydrodiol dehydrogenase of the TOL plasmid pWW0. (4/773)
We identified and characterized a methyl transfer activity of the toluate cis-dihydrodiol (4-methyl-3,5-cyclohexadiene-cis-1, 2-diol-1-carboxylic acid) dehydrogenase of the TOL plasmid pWW0 towards toluene cis-dihydrodiol (3-methyl-4,5-cyclohexadiene-cis-1, 2-diol). When the purified enzyme from the recombinant Escherichia coli containing the xylL gene was incubated with toluene cis-dihydrodiol in the presence of NAD+, the end products differed depending on the presence of adenosylcobalamin (coenzyme B12). The enzyme yielded catechol in the presence of adenosylcobalamin, while it gave 3-methylcatechol in the absence of the cofactor. Adenosylcobalamin was transformed to methylcobalamin as a result of the enzyme reaction, which indicates that the methyl group of the substrate was transferred to adenosylcobalamin. Other derivatives of the cobalamin such as aquo (hydroxy)- and cyanocobalamin did not mediate the methyl transfer reaction. The dehydrogenation and methyl transfer reactions were assumed to occur concomitantly, and the methyl transfer reaction seemed to depend on the dehydrogenation. To our knowledge, the enzyme is the first dehydrogenase that shows a methyl transfer activity as well. (+info)Determination of the urinary benzene metabolites S-phenylmercapturic acid and trans,trans-muconic acid by liquid chromatography-tandem mass spectrometry. (5/773)
To investigate how various levels of exposure affect the metabolic activation pathways of benzene in humans and to examine the relationship between urinary metabolites and other biological markers, we have developed a sensitive and specific liquid chromatographic-tandem mass spectrometric assay for simultaneous quantitation of urinary S-phenylmercapturic acid (S-PMA) and trans,trans-muconic acid (t,t-MA). The assay involves spiking urine samples with [13C6]S-PMA and [13C6]t,t-MA as internal standards and clean up of samples by solid-phase extraction with subsequent analysis by liquid chromatography coupled with electrospray-tandem mass spectrometry-selected reaction monitoring (LC-ES-MS/MS-SRM) in the negative ionization mode. The efficacy of this assay was evaluated in human urine specimens from smokers and non-smokers as the benzene-exposed and non-exposed groups. The coefficient of variation of runs on different days (n = 8) for S-PMA was 7% for the sample containing 9.4 microg S-PMA/l urine, that for t,t-MA was 10% for samples containing 0.07 mg t,t-MA/l urine. The mean levels of urinary S-PMA and t,t-MA in smokers were 1.9-fold (P = 0.02) and 2.1-fold (P = 0.03) higher than those in non-smokers. The mean urinary concentration (+/-SE) was 9.1 +/- 1.7 microg S-PMA/g creatinine [median 5.8 microg/g, ranging from not detectable (1 out of 28) to 33.4 microg/g] among smokers. In non-smokers' urine the mean concentration was 4.8 +/- 1.1 microg S-PMA/g creatinine (median 3.6 microg/g, ranging from 1.0 to 19.6 microg/g). For t,t-MA in smokers' urine the mean (+/-SE) was 0.15 +/- 0.03 mg/g creatinine (median 0.11 mg/ g, ranging from 0.005 to 0.34 mg/g); the corresponding mean value for t,t-MA concentration in non-smokers' urine was 0.07 +/- 0.02 mg/g creatinine [median 0.03 mg/g, ranging from undetectable (1 out of 18) to 0.48 mg/g]. There was a correlation between S-PMA and t,t-MA after logarithmic transformation (r = 0.41, P = 0.005, n = 46). (+info)Metabolism of [14C]phenol in the isolated perfused mouse liver. (6/773)
A previous report from this laboratory focused on the metabolism of [14C]benzene (BZ) in the isolated, perfused, mouse liver (C. C. Hedli, et al., 1997, Toxicol. Appl. Pharmacol. 146, 60-68). Whereas administration of BZ to mice results in bone marrow depression (R. Snyder et al., 1993, Res. Commun. Chem. Pathol. Pharmacol. 20, 191-194), administration of phenol (P), the major metabolite of BZ, does not. It was, therefore, of interest to determine whether the metabolic fate of P produced during BZ metabolism differed from that of P metabolized in the absence of BZ. Mouse livers were perfused with a solution of [14C]P in both the orthograde (portal vein to central vein) and retrograde (central vein to portal vein) direction to investigate the metabolic zonation of enzymes involved in P hydroxylation and conjugation. Perfusate samples were collected, separated by HPLC, and tested for radioactivity. Unconjugated metabolites were identified by comparing their retention times with nonradiolabeled standards, which were detected by UV absorption. Conjugated metabolites were identified and collected on the basis of radiochromatogram results, hydrolyzed enzymatically, and identified by co-chromatography with unlabeled BZ metabolites. The objective was to compare and quantify the metabolites formed during the perfusion of P in the orthograde and retrograde directions and to compare the orthograde P-perfusion results with the orthograde BZ results reported previously. Regardless of the direction of P perfusion, the major compounds released from the liver were P. phenylgucuronide, phenylsulfate, hydroquinone (HQ), and HQ glucuronide. A comparison of the results of perfusing P in the orthograde versus the retrograde direction showed that more P was recovered unchanged and more HQ was formed during retrograde perfusion. The results suggest that enzymes involved in P hydroxylation are generally closer to the central vein than those involved in conjugation, and that during retrograde perfusion, P metabolism may be limited by the sub-optimal conditions of perfusion. Comparison of the orthograde perfusion studies of P and BZ revealed that a larger percentage of the radioactivity released from the liver was identified as unconjugated HQ after BZ perfusion than after P perfusion. In addition, the amount of radioactivity covalently bound to liver macromolecules was measured after each perfusion and determined to be proportional to the amount of HQ and HQG detected in the perfusate samples. (+info)Environmental exposure to volatile organic compounds among workers in Mexico City as assessed by personal monitors and blood concentrations. (7/773)
Benzene, an important component in gasoline, is a widely distributed environmental contaminant that has been linked to known health effects in animals and humans, including leukemia. In Mexico City, environmental benzene levels, which may be elevated because of the heavy traffic and the poor emission control devices of older vehicles, may pose a health risk to the population. To assess the potential risk, portable passive monitors and blood concentrations were used to survey three different occupational groups in Mexico City. Passive monitors measured the personal exposure of 45 workers to benzene, ethylbenzene, toluene, o-xylene and m-/p-xylene during a work shift. Blood concentrations of the above volatile organic compounds (VOCs), methyl tert-butyl ether, and styrene were measured at the beginning and the end of a work shift. Passive monitors showed significantly higher (p > 0.0001) benzene exposure levels among service station attendants (median = 330 microg/m3; range 130-770) as compared to street vendors (median = 62 microg/m3; range 49-180) and office workers (median = 44 microg/m3, range 32-67). Baseline blood benzene levels (BBLs) for these groups were higher than those reported for similar populations from Western countries (median = 0.63 microg/L, n = 24 for service station attendants; median = 0.30 microg/L, n = 6 for street vendors; and median = 0.17 microgr;g/L, n = 7 for office workers). Nonsmoking office workers who were nonoccupationally exposed to VOCs had BBLs that were more than five times higher than those observed in a nonsmoking U.S. population. BBLs of participants did not increase during the work shift, suggesting that because the participants were chronically exposed to benzene, complex pharmacokinetic mechanisms were involved. Our results highlight the need for more complete studies to assess the potential benefits of setting environmental standards for benzene and other VOCs in Mexico. (+info)Microbial communities associated with anaerobic benzene degradation in a petroleum-contaminated aquifer. (8/773)
Microbial community composition associated with benzene oxidation under in situ Fe(III)-reducing conditions in a petroleum-contaminated aquifer located in Bemidji, Minn., was investigated. Community structure associated with benzene degradation was compared to sediment communities that did not anaerobically oxidize benzene which were obtained from two adjacent Fe(III)-reducing sites and from methanogenic and uncontaminated zones. Denaturing gradient gel electrophoresis of 16S rDNA sequences amplified with bacterial or Geobacteraceae-specific primers indicated significant differences in the composition of the microbial communities at the different sites. Most notable was a selective enrichment of microorganisms in the Geobacter cluster seen in the benzene-degrading sediments. This finding was in accordance with phospholipid fatty acid analysis and most-probable-number-PCR enumeration, which indicated that members of the family Geobacteraceae were more numerous in these sediments. A benzene-oxidizing Fe(III)-reducing enrichment culture was established from benzene-degrading sediments and contained an organism closely related to the uncultivated Geobacter spp. This genus contains the only known organisms that can oxidize aromatic compounds with the reduction of Fe(III). Sequences closely related to the Fe(III) reducer Geothrix fermentans and the aerobe Variovorax paradoxus were also amplified from the benzene-degrading enrichment and were present in the benzene-degrading sediments. However, neither G. fermentans nor V. paradoxus is known to oxidize aromatic compounds with the reduction of Fe(III), and there was no apparent enrichment of these organisms in the benzene-degrading sediments. These results suggest that Geobacter spp. play an important role in the anaerobic oxidation of benzene in the Bemidji aquifer and that molecular community analysis may be a powerful tool for predicting a site's capacity for anaerobic benzene degradation. (+info)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.
Benzene derivatives are chemical compounds that are derived from benzene, which is a simple aromatic hydrocarbon with the molecular formula C6H6. Benzene has a planar, hexagonal ring structure, and its derivatives are formed by replacing one or more of the hydrogen atoms in the benzene molecule with other functional groups.
Benzene derivatives have a wide range of applications in various industries, including pharmaceuticals, dyes, plastics, and explosives. Some common examples of benzene derivatives include toluene, xylene, phenol, aniline, and nitrobenzene. These compounds can have different physical and chemical properties depending on the nature and position of the substituents attached to the benzene ring.
It is important to note that some benzene derivatives are known to be toxic or carcinogenic, and their production, use, and disposal must be carefully regulated to ensure safety and protect public health.
Sorbic acid is a chemical compound that is commonly used as a preservative in various food and cosmetic products. Medically, it's not typically used as a treatment for any specific condition. However, its preservative properties help prevent the growth of bacteria, yeast, and mold, which can improve the safety and shelf life of certain medical supplies such as ointments and eye drops.
The chemical structure of sorbic acid is that of a carboxylic acid with two double bonds, making it a unsaturated fatty acid. It's naturally found in some fruits like rowanberries and serviceberries, but most commercial sorbic acid is synthetically produced.
Food-grade sorbic acid is generally recognized as safe (GRAS) by the U.S. Food and Drug Administration (FDA), and it has a wide range of applications in food preservation, including baked goods, cheeses, wines, and fruit juices. In cosmetics, it's often used to prevent microbial growth in products like creams, lotions, and makeup.
It is important to note that some people may have allergic reactions to sorbic acid or its salts (sorbates), so caution should be exercised when introducing new products containing these substances into personal care routines or diets.
Toluene is not a medical condition or disease, but it is a chemical compound that is widely used in various industrial and commercial applications. Medically, toluene can be relevant as a substance of abuse due to its intoxicating effects when inhaled or sniffed. It is a colorless liquid with a distinctive sweet aroma, and it is a common solvent found in many products such as paint thinners, adhesives, and rubber cement.
In the context of medical toxicology, toluene exposure can lead to various health issues, including neurological damage, cognitive impairment, memory loss, nausea, vomiting, and hearing and vision problems. Chronic exposure to toluene can also cause significant harm to the developing fetus during pregnancy, leading to developmental delays, behavioral problems, and physical abnormalities.
Hydroquinones are a type of chemical compound that belong to the group of phenols. In a medical context, hydroquinones are often used as topical agents for skin lightening and the treatment of hyperpigmentation disorders such as melasma, age spots, and freckles. They work by inhibiting the enzyme tyrosinase, which is necessary for the production of melanin, the pigment that gives skin its color.
It's important to note that hydroquinones can have side effects, including skin irritation, redness, and contact dermatitis. Prolonged use or high concentrations may also cause ochronosis, a condition characterized by blue-black discoloration of the skin. Therefore, they should be used under the supervision of a healthcare provider and for limited periods of time.
Xylenes are aromatic hydrocarbons that are often used as solvents in the industrial field. They are composed of two benzene rings with methyl side groups (-CH3) and can be found as a mixture of isomers: ortho-xylene, meta-xylene, and para-xylene.
In a medical context, xylenes may be relevant due to their potential for exposure in occupational settings or through environmental contamination. Short-term exposure to high levels of xylenes can cause irritation of the eyes, nose, throat, and lungs, as well as symptoms such as headache, dizziness, and nausea. Long-term exposure has been linked to neurological effects, including memory impairment, hearing loss, and changes in behavior and mood.
It is worth noting that xylenes are not typically considered a direct medical diagnosis, but rather a potential exposure hazard or environmental contaminant that may have health impacts.
Phenol, also known as carbolic acid, is an organic compound with the molecular formula C6H5OH. It is a white crystalline solid that is slightly soluble in water and has a melting point of 40-42°C. Phenol is a weak acid, but it is quite reactive and can be converted into a variety of other chemicals.
In a medical context, phenol is most commonly used as a disinfectant and antiseptic. It has a characteristic odor that is often described as "tarry" or " medicinal." Phenol is also used in some over-the-counter products, such as mouthwashes and throat lozenges, to help kill bacteria and freshen breath.
However, phenol is also a toxic substance that can cause serious harm if it is swallowed, inhaled, or absorbed through the skin. It can cause irritation and burns to the eyes, skin, and mucous membranes, and it can damage the liver and kidneys if ingested. Long-term exposure to phenol has been linked to an increased risk of cancer.
Because of its potential for harm, phenol is regulated as a hazardous substance in many countries, and it must be handled with care when used in medical or industrial settings.
Occupational exposure refers to the contact of an individual with potentially harmful chemical, physical, or biological agents as a result of their job or occupation. This can include exposure to hazardous substances such as chemicals, heavy metals, or dusts; physical agents such as noise, radiation, or ergonomic stressors; and biological agents such as viruses, bacteria, or fungi.
Occupational exposure can occur through various routes, including inhalation, skin contact, ingestion, or injection. Prolonged or repeated exposure to these hazards can increase the risk of developing acute or chronic health conditions, such as respiratory diseases, skin disorders, neurological damage, or cancer.
Employers have a legal and ethical responsibility to minimize occupational exposures through the implementation of appropriate control measures, including engineering controls, administrative controls, personal protective equipment, and training programs. Regular monitoring and surveillance of workers' health can also help identify and prevent potential health hazards in the workplace.
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.
Catechols are a type of chemical compound that contain a benzene ring with two hydroxyl groups (-OH) attached to it in the ortho position. The term "catechol" is often used interchangeably with "ortho-dihydroxybenzene." Catechols are important in biology because they are produced through the metabolism of certain amino acids, such as phenylalanine and tyrosine, and are involved in the synthesis of various neurotransmitters and hormones. They also have antioxidant properties and can act as reducing agents. In chemistry, catechols can undergo various reactions, such as oxidation and polymerization, to form other classes of compounds.
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.
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.
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 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.
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.
I'm sorry for any confusion, but "hydrocarbons" is not a term that has a specific medical definition. Hydrocarbons are organic compounds consisting entirely of hydrogen and carbon. They are primarily used in industry as fuel, lubricants, and as raw materials for the production of plastics, fibers, and other chemicals.
However, in a broader scientific context, hydrocarbons can be relevant to medical discussions. For instance, in toxicology, exposure to certain types of hydrocarbons (like those found in gasoline or solvents) can lead to poisoning and related health issues. In environmental medicine, the pollution of air, water, and soil with hydrocarbons is a concern due to potential health effects.
But in general clinical medicine, 'hydrocarbons' wouldn't have a specific definition.
The chemical industry is a broad term that refers to the companies and organizations involved in the production or transformation of raw materials or intermediates into various chemical products. These products can be used for a wide range of applications, including manufacturing, agriculture, pharmaceuticals, and consumer goods. The chemical industry includes businesses that produce basic chemicals, such as petrochemicals, agrochemicals, polymers, and industrial gases, as well as those that manufacture specialty chemicals, such as dyestuffs, flavors, fragrances, and advanced materials. Additionally, the chemical industry encompasses companies that provide services related to the research, development, testing, and distribution of chemical products.
Cyclohexanes are organic compounds that consist of a six-carbon ring arranged in a cyclic structure, with each carbon atom joined to two other carbon atoms by single bonds. This gives the molecule a shape that resembles a hexagonal ring. The carbons in the ring can be saturated, meaning that they are bonded to hydrogen atoms, or they can contain double bonds between some of the carbon atoms.
Cyclohexanes are important intermediates in the production of many industrial and consumer products, including plastics, fibers, dyes, and pharmaceuticals. They are also used as solvents and starting materials for the synthesis of other organic compounds.
One of the most well-known properties of cyclohexane is its ability to exist in two different conformations: a "chair" conformation and a "boat" conformation. In the chair conformation, the carbon atoms are arranged in such a way that they form a puckered ring, with each carbon atom bonded to two other carbons and two hydrogens. This conformation is more stable than the boat conformation, in which the carbon atoms form a flattened, saddle-shaped ring.
Cyclohexanes are relatively nonpolar and have low water solubility, making them useful as solvents for nonpolar substances. They also have a relatively high boiling point compared to other hydrocarbons of similar molecular weight, due to the fact that they can form weak intermolecular forces called London dispersion forces.
Cyclohexane is a flammable liquid with a mild, sweet odor. It is classified as a hazardous substance and should be handled with care. Exposure to cyclohexane can cause irritation of the eyes, skin, and respiratory tract, and prolonged exposure can lead to more serious health effects, including neurological damage.
Chlorobenzenes are a group of chemical compounds that consist of a benzene ring (a cyclic structure with six carbon atoms in a hexagonal arrangement) substituted with one or more chlorine atoms. They have the general formula C6H5Clx, where x represents the number of chlorine atoms attached to the benzene ring.
Chlorobenzenes are widely used as industrial solvents, fumigants, and intermediates in the production of other chemicals. Some common examples of chlorobenzenes include monochlorobenzene (C6H5Cl), dichlorobenzenes (C6H4Cl2), trichlorobenzenes (C6H3Cl3), and tetrachlorobenzenes (C6H2Cl4).
Exposure to chlorobenzenes can occur through inhalation, skin contact, or ingestion. They are known to be toxic and can cause a range of health effects, including irritation of the eyes, skin, and respiratory tract, headaches, dizziness, nausea, and vomiting. Long-term exposure has been linked to liver and kidney damage, neurological effects, and an increased risk of cancer.
It is important to handle chlorobenzenes with care and follow appropriate safety precautions to minimize exposure. If you suspect that you have been exposed to chlorobenzenes, seek medical attention immediately.
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.
Benzene
Claus' benzene
Benzene (disambiguation)
Benzene hexachloride
Diacetoxyiodo)benzene
Benzene Convention
Deuterated benzene
Dewar benzene
hydroxyamino)benzene mutase
Benzene (data page)
Benzene)chromium tricarbonyl
Bis(benzene)chromium
Benzene)ruthenium dichloride dimer
Benzene 1,2-dioxygenase
Bis(trifluoroacetoxy)iodo)benzene
Benzene in soft drinks
Benzene-1,2-dithiol
1,2-Bis(dichlorophosphino)benzene
1,2-Bis(diphenylphosphino)benzene
1,2-Bis(dimethylarsino)benzene
1,4-Bis(trichloromethyl)benzene
C3-Benzenes
C4-Benzenes
C2-Benzenes
Oil refinery
Retro-Diels-Alder reaction
Price Landfill
Diesel exhaust
Johannes Thiele (chemist)
Linus Pauling
Benzene - Wikipedia
Benzene | ToxFAQs™ | ATSDR
Benzene Factsheet | National Biomonitoring Program | CDC
CCOHS: Benzene
CDC | Facts About Benzene
CDC - NIOSH Pocket Guide to Chemical Hazards - Benzene
4W52: T4 Lysozyme L99A with Benzene Bound
Benzene, (3-bromopropoxy)
CDC Benzene | Emergency Preparedness & Response
Dewar benzene - American Chemical Society
Benzene, 1,4-difluoro
Carcinogenic effects of benzene: Cesare Maltoni's contributions
The Best Benzene-Free Dry Shampoos & Alternatives for Refreshed Hair
EWG Tap Water Database | Utilities Inc. - Lake Village SD | Benzene
Mystery of benzene's structure finally revealed
Tri-Alpha-Napthyl Benzene as a Crystalline or Glassy MALDI Matrix | NIST
1-bromo-4-fluoro-2-methyl-benzene
Benzene in Deodorant and Body Sprays - ConsumerLab.com
Benzene Levels | Technology Trends
Benzene found in more dry shampoo products, report says
Benzene-1,2-d2 | C6H4D2 | ChemSpider
bonding in benzene - sp2 hybridisation and delocalisation
Induction effects in metal cation-benzene complexes | BSC-CNS
benzene | Health Topics | NutritionFacts.org
All in a Typical Day with Benzene
Distance-to-target graph for the benzene limit value, 2010 - European Environment Agency
Benzene Exposure Archives - Simmons Hanly Conroy
CDC | Facts About Benzene
Exposure to benzene10
- How can families reduce the risks of exposure to benzene? (cdc.gov)
- Moving to an area with fresh air is a good way to reduce the possibility of death from exposure to benzene in the air. (cdc.gov)
- Employers have requirements under The Control of Substances Hazardous to Health Regulations 2002 (COSHH) to assess and control worker exposure to benzene. (hsl.gov.uk)
- The improvements to control measures and working practice, made in light of the elevated biological monitoring results, resulted in significant reductions in worker exposure to benzene. (hsl.gov.uk)
- Exposure to benzene can occur by inhalation, orally, and through the skin. (fda.gov)
- HarrisMartin's Benzene & Emerging Toxic Torts Litigation Report will track recent developments in litigation stemming from exposure to benzene, as well as a number of other emerging areas of toxic tort litigation, such as talc, silica, pesticides and other chemical exposures. (harrismartin.com)
- Exposure to benzene in sufficient quantities increases the risk of cancer. (foodnavigator-usa.com)
- Benzene is a carcinogen, and exposure to Benzene can cause blood disorders, such as leukemia. (yourlawyer.com)
- Exposure to benzene, a carcinogen released at oil and gas refineries, can cause vomiting, headaches, anemia, increased risk of cancer and death, according to the U.S. Centers for Disease Control and Prevention. (publicnewsservice.org)
- Characterizing exposure to benzene , toluene, and naphthalene in firefighters wearing different types of new or laundered PPE. (cdc.gov)
High levels of benzene7
- Some women who breathed high levels of benzene for many months had irregular menstrual periods and a decrease in the size of their ovaries, but we do not know for certain that benzene caused the effects. (cdc.gov)
- Long-term exposure to high levels of benzene in the air can cause leukemia, particularly acute myelogenous leukemia, often referred to as AML. (cdc.gov)
- Eating or drinking foods containing high levels of benzene can cause vomiting, irritation of · Industrial processes are the main source of benzene the stomach, dizziness, sleepiness, convulsions, rapid in the environment. (cdc.gov)
- Certain metabolites can be measured in the Long-term exposure to high levels of benzene in the urine. (cdc.gov)
- Long-term exposure to high levels of benzene in the air can cause leukemia, cancer of the blood-forming organs. (cdc.gov)
- Valisure, an independent lab, and pharmacy that tests drug products' quality and safety, states that they discovered high-levels of Benzene in 20 different brands of hand sanitizer. (yourlawyer.com)
- The detection of high levels of benzene in body sprays is cause for significant concern since these products are often used daily, by both adults and adolescents," says David Light, Founder and CEO of Valisure. (mamavation.com)
Higher levels of benzene4
- Air around hazardous waste sites or gas stations will contain higher levels of benzene. (cdc.gov)
- Biomonitoring studies on levels of benzene provide physicians and public health officials with reference values so that they can determine whether people have been exposed to higher levels of benzene than are found in the general population. (cdc.gov)
- contain higher levels of benzene. (cdc.gov)
- The air around hazardous waste sites or gas stations can contain higher levels of benzene than in other areas. (cdc.gov)
Carcinogen7
- The Department of Health and Human Services (DHHS) has determined that benzene is a known carcinogen. (cdc.gov)
- Human Services (DHHS) has determined that benzene is a exposed to, since the metabolites may be present in urine known carcinogen. (cdc.gov)
- In 1976, Maltoni reported that benzene is a potent experimental carcinogen. (nih.gov)
- Thus, benzene was shown to be a multipotential carcinogen that produced cancers in several species of animals by various routes of administration. (nih.gov)
- Benzene is a known human carcinogen. (ewg.org)
- Risk Statement: Benzene is classified as a human carcinogen. (fda.gov)
- Benzene is defined as a carcinogen and its main exposure routes into our bodies are through inhalation, skin absorption, ingestion, skin, and/or eye contact. (mamavation.com)
Heightened benzene levels1
- While it's a holy grail product for so many, it's also important to note that tons of dry shampoos have been recalled due to the finding of heightened benzene levels. (eonline.com)
Limit for benzene3
- The legal limit for benzene, established in 1987, was based on analytical detection limits at the time that the standard was set. (ewg.org)
- The safety limit for benzene in drinking water is one microgram. (nutritionfacts.org)
- Risk assessment identified that subsequent dilution of the product following manufacturers instructions would have ensured the product, as consumed, was below the 10ppb action limit for benzene. (fsai.ie)
Sources of benzene include1
- Natural sources of benzene include emissions from volcanoes and forest fires. (cdc.gov)
Determined that benzene is carcinogenic1
- The International Agency for Research on Cancer (IARC) and the EPA have determined that benzene is carcinogenic to humans. (cdc.gov)
Flammable3
- Benzene is a colorless and highly flammable liquid with a sweet smell, and is partially responsible for the aroma of gasoline. (wikipedia.org)
- He heated it and created a flammable gas he called bicarburet of hydrogen, later renamed benzene. (energyindepth.org)
- Benzene is a highly flammable liquid which also has some health effects. (hsl.gov.uk)
Concentrations7
- Long-term exposure to lower concentrations of benzene can result in bone marrow suppression leading to serious blood disorders such as anaemia, forms of leukaemia and other cancers of the white blood cells. (hsl.gov.uk)
- The mean benzene concentrations in a puff ranged from 1 to 2 x 10(5) micrograms/m3 for cigars, RYO cigarette and pipe tobaccos. (nih.gov)
- According to Dr. Leonardo Trasande, a professor at the NYU Grossman School of Medicine, the FDA permitted Benzene concentrations up to two parts per million. (yourlawyer.com)
- Benzene , toluene, and naphthalene were found to diffuse through and/or around the turnout jacket, as inside jacket benzene concentrations were often near levels reported outside the turnout jacket (9.7-11.7% median benzene reduction from outside the jacket to inside the jacket). (cdc.gov)
- Benzene concentrations in exhaled breath increased significantly from pre to post fire for all three groups (p-values (cdc.gov)
- The difference of pre-to post-fire benzene exhaled breath concentrations were positively associated with inside jacket and outside jacket benzene concentrations, even though self-contained breathing apparatus (SCBA) were worn during each response. (cdc.gov)
- Using Radiello passive samplers, it was found that benzene concentrations were above recommended international standards. (who.int)
Toxic chemical benzene1
- Two more popular antiperspirants have been recalled after they were found to contain the toxic chemical benzene. (consumerlab.com)
Detectable levels2
- From Eva NYC , a brand that tested its aerosols for benzene and came back with no detectable levels, to Geologie's transformative co-wash that adds life to your hair while extending time between washes, you can trust these products to give you revitalized feeling and looking hair without exposing you to carcinogens. (eonline.com)
- According to the news report, the leading hand sanitizer brand, Purell, and several others did not have detectable levels of Benzene. (yourlawyer.com)
Colorless2
Cancer-causing3
- HOUSTON, Texas -- Ten U.S. oil refineries, including six in Texas, have released levels of cancer-causing benzene into nearby communities above Environmental Protection Agency limits requiring companies to take action to reduce pollution. (publicnewsservice.org)
- Cancer-causing benzene was recently detected in some of the most popular American deodorants & antiperspirants sold in American retail stores. (mamavation.com)
- You've trusted Mamavation to bring you topics like best air purifiers , safest cookware without PFAS , & safest green beauty makeup sans PFAS , now join us for a special report released detecting cancer-causing benzene in some of the most popular deodorants sold to Americans. (mamavation.com)
Amount of benzene3
- By measuring benzene in blood, scientists can estimate the amount of benzene that has entered people's bodies. (cdc.gov)
- Finding a measurable amount of benzene in the blood does not imply that levels of benzene cause an adverse health effect. (cdc.gov)
- The Food & Drug Administration has warned that no amount of benzene is safe for use in personal care products. (mamavation.com)
Effects of benzene2
- What are the potential health effects of benzene? (ccohs.ca)
- The effects of benzene exposure can include: headaches, tiredness, nausea, dizziness and unconsciousness if exposure is very high (thousands of ppm). (hsl.gov.uk)
Presence of benzene2
- The report comes after certain aerosol dry shampoos, including some Dove, Nexxus, Suave, Tigi and Tresemme products, were voluntarily recalled last month due to the potential presence of benzene. (wowt.com)
- WHIPPANY, N.J., October 1, 2021 -- Bayer is voluntarily recalling all unexpired Lotrimin® AF and Tinactin® spray products with lot numbers beginning with TN, CV or NAA, distributed between September 2018 to September 2021, to the consumer level due to the presence of benzene in some samples of the products. (fda.gov)
Known whether benzene2
20211
- Benzene, which has been linked to blood cancers, has been reported in spray deodorants and antiperspirants that were independently tested in 2021. (consumerlab.com)
Inhalation2
- Maltoni's experiments clearly demonstrated that benzene is carcinogenic in Sprague-Dawley rats, Wistar rats, Swiss mice, and RF/J mice when administered by inhalation or ingestion. (nih.gov)
- 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)
Toluene3
- The smoke may contain ultra-fine particles, toxic compounds (e.g., benzene, toluene, hydrogen cyanide), viruses (e.g., human papilloma virus [HPV]), and cancer cells (Guideline for Surgical Smoke Safety). (cdc.gov)
- The pollutants released include benzene, toluene, ethylbenzene and xylenes (BTEX), which are significant due to their high level of toxicity. (who.int)
- Additionally, there were incidences where individuals were at potential hazard risk of benzene and toluene that may pose non-carcinogenic effects to employees. (who.int)
Levels31
- Outdoor air contains low levels of benzene from tobacco smoke, automobile service stations, exhaust from motor vehicles, and industrial emissions. (cdc.gov)
- Outdoor air contains low levels of benzene from evaporates into the air very quickly and dissolves slightly tobacco smoke, automobile service stations, exhaust in water. (cdc.gov)
- Outdoor air contains low levels of benzene from tobacco smoke, gas stations, motor vehicle exhaust, and industrial emissions. (cdc.gov)
- Indoor air generally contains levels of benzene higher than those in outdoor air. (cdc.gov)
- People working in industries that make or use benzene may be exposed to the highest levels of it. (cdc.gov)
- and benzene standards and permissible exposure levels. (nih.gov)
- Gray News) - An independent lab has found troubling levels of the cancer-causing chemical benzene in more types of dry shampoo products, according to a new report from Valisure. (wowt.com)
- On Monday, Valisure sent a citizen petition to the Food and Drug Administration saying 70% of samples from 34 different brands of dry shampoo showed quantifiable levels of benzene. (wowt.com)
- Realistically, not only have benzene levels been proven to have little or no connection to shale gas development but the effects have been widely exaggerated. (energyindepth.org)
- Which beverages have been found to have benzene levels exceeding safety standards? (nutritionfacts.org)
- Well, this year, another beverage was found to have benzene levels exceeding safety standards. (nutritionfacts.org)
- however, benzene levels began to rise rapidly and went well in excess of the UK workplace exposure limit. (hsl.gov.uk)
- Biological monitoring enabled the job to be completed whilst giving continued assurance that the workforce was not being exposed to potentially hazardous levels of benzene. (hsl.gov.uk)
- The results suggest that smoking cigars, pipes or RYO cigarettes leads to potential exposures which exceed the No Significant Risk levels of benzene and BaP set pursuant to California's Proposition 65. (nih.gov)
- The resulting historical sequence has then been compared with the dates when changes in regulatory levels of benzene were proposed by a number of industrial safety committees. (karger.com)
- From the analyses, it is clear that the decision of other 'key' committees is more important than the changes in the toxicological database in prompting changes in regulatory levels of benzene. (karger.com)
- Voluntary recalls of finished pharmaceutical products and consumer products associated with benzene levels above USP safety limits highlight the importance of analytical testing for toxic substances in finished pharmaceutical and consumer products. (intertek.com)
- All of the follow-up samples on Roses' Diabetic Orange Squash contained undetectable levels of benzene, whereas four out of the five C&C Diet Club Lemon drinks contained benzene levels above 10 ppb. (fsai.ie)
- Another sample of C&C Club Orange was also taken for comparison purposes but this was shown to have undetectable levels of benzene. (fsai.ie)
- During the survey it was noted that the two beverage products that were found to contain elevated benzene levels had been purchased by FSAI from retailers when the products were past their best before date. (fsai.ie)
- The results indicate that the levels of benzene found in soft drinks, squashes and flavoured waters to date do not pose a safety concern for consumers. (fsai.ie)
- Almost all of the samples tested in this survey (97.4%) contained benzene below analytical detection levels or levels below 10ppb (the WHO guidelines for safe levels in drinking water which was used as an appropriate comparator in this survey). (fsai.ie)
- Appropriate action has been taken by the Irish manufacturer and Irish distributor, respectively, of the two products on the Irish market that were found to have elevated levels of benzene. (fsai.ie)
- Both food safety authorities and the soft drinks industry have re-iterated that there was no health risk to consumers in the benzene levels found in drinks. (foodnavigator-usa.com)
- WASHINGTON, DC - A news report on cbsnews.com states that an independent study is warning that some hand sanitizer products may have unsafe levels of Benzene. (yourlawyer.com)
- The report states that during the initial days of the coronavirus pandemic, the U.S. Food and Drug Administration relaxed quality standards on Benzene levels in liquid hand sanitizers. (yourlawyer.com)
- Deer Park and Galena Park were under shelter-in-place orders for several hours after air quality readings showed elevated levels of benzene. (khou.com)
- ITC believes the increase in benzene levels was caused by a shifting of the foam in one of the tanks, according to ITC spokeswoman Alice Richardson. (khou.com)
- The spokeswoman, who broke down at one point during the news conference, said she can't give an exact timeline on how long the elevated levels of benzene will last. (khou.com)
- Harris County Public Health tweeted: "We are diligently monitoring areas where elevated benzene levels were detected this AM. Fortunately, those levels are dropping substantially. (khou.com)
- Title : Maternal Exposure to Ambient Levels of Benzene and Neural Tube Defects among Offspring: Texas, 1999-2004 Personal Author(s) : Lupo, Philip J.;Symanski, Elaine;Waller, D. Kim;Chan, Wenyaw;Langlois, Peter H.;Canfield, Mark A.;Mitchell, Laura E. (cdc.gov)
Contain benzene5
- Vapors (or gases) from products that contain benzene, such as glues, paints, furniture wax, and detergents, can also be a source of exposure. (cdc.gov)
- The benzene in indoor air comes from products that contain benzene such as glues, paints, furniture wax, and detergents. (cdc.gov)
- When a sample was found to contain benzene above 10 ppb, follow-up samples were taken by the Environmental Health Service with different batch codes and different best before dates and supplied to the laboratory for analysis. (fsai.ie)
- Table 2 presents the results for the follow-up samples for the two products found to contain benzene above the 10ppb limit. (fsai.ie)
- However, Valisure has asked the U.S. Food and Drug Administration to investigate and recall the hand sanitizer products found to contain Benzene. (yourlawyer.com)
Soft drinks9
- Soft drinks and juice drinks with certain natural juices like strawberries, cranberries, or other ground fruits showed higher amounts of benzene. (energyindepth.org)
- Speaking of toxic chemicals, last year we learned that some soft drinks have benzene in them. (nutritionfacts.org)
- Soft drinks industry officials will meet this September to discuss progress on cutting benzene residues out of their drinks, six months after BeverageDaily.com revealed there was still a problem. (foodnavigator-usa.com)
- European soft drinks association UNESDA will use September's general meeting, set to include industry representatives from 27 European countries, to discuss how a new industry guidance document on limiting benzene formation in drinks is being implemented. (foodnavigator-usa.com)
- Concerns over benzene residues in soft drinks has spread around the world since a scientist for the US Food and Drug Administration told BeverageDaily.com the agency had found more benzene in some soft drinks than is allowed in drinking water. (foodnavigator-usa.com)
- "It is perplexing," said Andrew Rainer, a lawyer suing several soft drinks firms, including Coca-Cola, over benzene in the US. (foodnavigator-usa.com)
- Some soft drinks firms may have been out of the loop on benzene, said Kevin Keane, spokesperson for the American Beverages Association, in February. (foodnavigator-usa.com)
- For this reason, Beaumont rejected calls to put a limit on benzene residues in soft drinks. (foodnavigator-usa.com)
- Several lawsuits have been filed against soft drinks firms in the US after independent lab tests there found benzene in drinks samples above the US five ppb water limit. (foodnavigator-usa.com)
Contamination3
- ConsumerLab's staff has analyzed the results of these tests and identified which products we think should be avoided and which are safest with regard to benzene contamination. (consumerlab.com)
- The petition urges the FDA to "expeditiously request recalls" on the affected batches of products containing benzene and better define limits for benzene contamination in other products. (wowt.com)
- Although air monitoring had identified 'hot spots' of benzene contamination, the intermittent nature of these and the extensive use of PPE meant that it was not sufficient to assess the risk of exposure. (hsl.gov.uk)
Emissions2
Benzol1
- The hydrocarbon derived from benzoic acid thus acquired the name benzin, benzol, or benzene. (wikipedia.org)
Carcinogenic1
- The World Health Organization and the International Agency for Research on Cancer have classified benzene as a Group 1 compound, defining it as "carcinogenic to humans. (wowt.com)
Hydrogen6
- The benzene molecule is composed of six carbon atoms joined in a planar hexagonal ring with one hydrogen atom attached to each. (wikipedia.org)
- Because it contains only carbon and hydrogen atoms, benzene is classed as a hydrocarbon. (wikipedia.org)
- Michael Faraday first isolated and identified benzene in 1825 from the oily residue derived from the production of illuminating gas, giving it the name bicarburet of hydrogen. (wikipedia.org)
- The empirical formula for benzene was long known, but its highly polyunsaturated structure, with just one hydrogen atom for each carbon atom, was challenging to determine. (wikipedia.org)
- It is a debate that in recent years has taken on added urgency, because benzene - comprising six carbon atoms matched with six hydrogen atoms - is the smallest molecule that can be used in the production of opto-electronic materials, which are revolutionising renewable energy and telecommunications tech. (cosmosmagazine.com)
- Benzene is built from hydrogen atoms (1s 1 ) and carbon atoms (1s 2 2s 2 2p x 1 2p y 1 ). (chemguide.co.uk)
Carbon3
- Due to the cyclic continuous pi bonds between the carbon atoms, benzene is classed as an aromatic hydrocarbon. (wikipedia.org)
- The difference in benzene is that each carbon atom is joined to two other similar carbon atoms instead of just one. (chemguide.co.uk)
- They may be grouped further into aliphatic-chain compounds, such as n -hexane, and as aromatic compounds with a 6-carbon ring, such as benzene or xylene. (medscape.com)
Molecule3
- He said that he had discovered the ring shape of the benzene molecule after having a reverie or day-dream of a snake biting its own tail (a symbol in ancient cultures known as the ouroboros). (wikipedia.org)
- Earlier this month, Molecule of the Week brought you the venerable and extremely hazardous molecule benzene . (acs.org)
- This week's molecule has one of the structures that was originally proposed for benzene: bicyclo[2.2.0]hexa-2,5-diene. (acs.org)
Michael Faraday1
- Benzene was first identified in the early 1800's by Michael Faraday, a famous scientist of the time. (energyindepth.org)
Volatile3
- Benzene is a volatile organic compound. (wikipedia.org)
- Benzene belongs to a class of chemicals called volatile organic compounds, so called because they evaporate in the air. (cdc.gov)
- Soil samples had indicated the presence of various volatile organic chemicals, of which benzene was the major component. (hsl.gov.uk)
Phenyl2
- HSE measured a specific metabolite of benzene called S-phenyl mercapturic acid (SPMA) in urine samples from exposed workers. (hsl.gov.uk)
- r\nTo clarify what is meant by electron-donating and electron-withdrawing substituents: Any substituent whose first atom (the one that's attached to the benzene ring) has a lone pair will be a pi electron donor to the phenyl ring, as shown in the resonance structure in the next figure. (dummies.com)
Electrons3
- Measuring a system that complex - and tiny - has until now proved impossible, meaning that the precise behaviour of benzene electrons could not be discovered. (cosmosmagazine.com)
- This upsets examiners because a pi bond can only hold 2 electrons - whereas in benzene there are 6 delocalised electrons. (chemguide.co.uk)
- They deactivate the ring as a result of being highly electronegative groups, pulling electrons away from the benzene ring toward themselves, making the ring less nucleophilic. (dummies.com)
Evaporates2
- Benzene evaporates into the air very quickly. (cdc.gov)
- Benzene, a chemical with a slightly sweet odor, evaporates from gasoline and oil, and is used in plastics, pesticides and other products. (publicnewsservice.org)
Valisure3
- Valisure examined hundreds of hand sanitizer products for Benzene. (yourlawyer.com)
- According to Valisure, twenty-one hand sanitizer products from 15 different brands tested above the FDA's interim Benzene limit. (yourlawyer.com)
- Benzene, a chemical known to cause cancer in humans, was found in over 40 different deodorant products sold to Americans in a new consumer study conducted by Valisure . (mamavation.com)
Sprays3
- It is likely that the benzene in these products arose from other ingredients they contain, such as butane, isobutane, or propane, which are propellants in sprays. (consumerlab.com)
- Download this Application Note to learn what our scientists determined when analyzing various sunscreen and propellant sprays for benzene at trace level. (intertek.com)
- The researchers were not sure how benzene found its way into these products, but they surmised that it could be coming from the processing of ingredients like butane or propellants inside the sprays. (mamavation.com)
Substances1
- Gradually, the sense developed among chemists that a number of substances were chemically related to benzene, comprising a diverse chemical family. (wikipedia.org)
Molecular formula1
- Benzene is an organic chemical compound with the molecular formula C6H6. (wikipedia.org)
Hazardous2
- use benzene to make other chemicals which are used to · Air around hazardous waste sites or gas stations will make plastics, resins, and nylon and other synthetic fibers. (cdc.gov)
- Benzene leaks from underground storage tanks or from hazardous waste sites containing benzene can contaminate well water. (cdc.gov)
Gasoline4
- Benzene is also a natural part of crude oil, gasoline, and cigarette smoke. (cdc.gov)
- Benzene exposure can be reduced by limiting contact with gasoline and cigarette smoke. (cdc.gov)
- Benzene is made from coal and petroleum sources and is present in gasoline. (cdc.gov)
- People who work with petroleum products, including gasoline, are exposed to benzene by touching or breathing in the chemical. (cdc.gov)
Found5
- Benzene has been found in at least 1,000 of the 1,684 National Priority List sites identified by the Environmental Protection Agency (EPA). (cdc.gov)
- CDC researchers found benzene present in the blood of the majority of participants. (cdc.gov)
- Benzene was found in 44 out of 86 distinct products from 30 brands of spray deodorants and antiperspirants. (consumerlab.com)
- Benzene is found in the environment from natural sources and human activity. (fda.gov)
- But, Coca-Cola was hit with fresh charges after tests found one of its new Vault Zero drinks with 13ppb benzene. (foodnavigator-usa.com)
Hand sanitizers1
- These findings build upon our now validated discovery of benzene in sunscreens, after-sun care products, and hand sanitizers that have already been followed by national recalls earlier this year. (mamavation.com)
Compounds3
- Kekulé's 1872 modification of his 1865 theory, illustrating rapid alternation of double bonds The new understanding of benzene, and hence of all aromatic compounds, proved to be so important for both pure and applied chemistry that in 1890 the German Chemical Society organized an elaborate appreciation in Kekulé's honor, celebrating the twenty-fifth anniversary of his first benzene paper. (wikipedia.org)
- Benzene ranks as one of the top 20 chemicals in use today for production processes in the U.S. 20-30 million tons of benzene is produced annually in the U.S. It is a super chemical and father of many other chemical compounds in many of the common products we use every day. (energyindepth.org)
- The applicable subheading for 1-Isocyanato-3-(trifluoromethyl)benzene also known as a,a,a,-Trifluoro-m-tolyl isocyanate will be 2929.10.2700 , Harmonized Tariff Schedule of the United States (HTS), which provides for compounds with other nitrogen function: isocyanates: 1-Isocyanato-3-(trifluoromethyl)-benzene. (faqs.org)
Antiperspirants1
- Which deodorants and antiperspirants are contaminated with benzene and which are not? (consumerlab.com)
Long-term exposure1
- The major effect of benzene from long-term exposure is on the blood. (cdc.gov)
Chemicals9
- Some industries use benzene to make other chemicals which are used to make plastics, resins, and nylon and other synthetic fibers. (cdc.gov)
- As one of the most commonly-made chemicals in the United States, benzene is often used to make many other chemicals. (cdc.gov)
- In the Fourth National Report on Human Exposure to Environmental Chemicals (Fourth Report) , CDC scientists measured benzene in the blood of 1,345 participants aged twenty years and older who took part in the National Health and Nutrition Examination Survey (NHANES) during 2003-2004. (cdc.gov)
- it ranks in the benzene, such as glues, paints, furniture wax, and top 20 chemicals for production volume. (cdc.gov)
- Benzene was among the 400 or more chemicals that Maltoni and his associates tested for carcinogenicity. (nih.gov)
- Benzene is one of those chemicals we hear about often in the discussion over natural gas development. (energyindepth.org)
- As a health professional and mother, I feel the impacts of chemicals like benzene are something we should be educated on, so I took the time to do a little research into its risks and sources of emission. (energyindepth.org)
- I wondered about the chemical composition of pine and how that relates to chemicals today, especially benzene. (energyindepth.org)
- The TAGA (trace atmospheric gas analyzer) has not had any significant hits for benzene or other chemicals. (khou.com)
Toxicity1
- Although benzene is a major industrial chemical, it finds limited use in consumer items because of its toxicity. (wikipedia.org)
Chemical9
- Curiously, a similar, humorous depiction of benzene had appeared in 1886 in a pamphlet entitled Berichte der Durstigen Chemischen Gesellschaft (Journal of the Thirsty Chemical Society), a parody of the Berichte der Deutschen Chemischen Gesellschaft, only the parody had monkeys seizing each other in a circle, rather than snakes as in Kekulé's anecdote. (wikipedia.org)
- Benzene is a widely used chemical formed from both natural processes and human activities. (cdc.gov)
- Benzene is considered to be a cancer-causing chemical. (cdc.gov)
- HIGHTLIGHTS: Benzene is a widely used chemical formed from both natural processes and human activities. (cdc.gov)
- If you are near a release of benzene, emergency coordinators may tell you to either evacuate the area or to "shelter in place" inside a building to avoid being exposed to the chemical. (cdc.gov)
- Spectroscopic observations and chemical conversions confirmed the Dewar benzene structure. (acs.org)
- On November 2, 1977, Chemical Week reported that Maltoni provided a "bombshell" when he demonstrated the "first direct link" between benzene and cancer. (nih.gov)
- Benzene is a dangerous chemical not many people realize is being used at manufacturing facilities in their towns and communities. (simmonsfirm.com)
- Pursuant to section 74 of the Canadian Environmental Protection Act, 1999 (CEPA 1999), the Ministers of the Environment and of Health have conducted a screening assessment on benzene, 1-methyl-2-nitro- (2-nitrotoluene), Chemical Abstracts Service Registry Number 88-72-2. (gc.ca)
Forest fires1
- That lead to an internet search that showed benzene is produced naturally by volcanoes, forest fires, and any incomplete combustion like cigarette smoke. (energyindepth.org)
Products9
- In the body, benzene is converted to products called metabolites. (cdc.gov)
- Also see our article about benzene in sun care products . (consumerlab.com)
- So I guess I should be terribly alarmed with benzene products surrounding me and infiltrating my life! (energyindepth.org)
- But further research showed that most products do not emit benzene, or only a trace amount, and the EPA allows an exposure/consumption level of 5 parts per billion even in our drinking water. (energyindepth.org)
- Lithium or sodium reduction of [SiN Dipp Be] in benzene, provides the relevant organoberyllate products, [{SiN Dipp BePh}M] (M = Li or Na), via the presumed intermediacy of transient Be( I ) radicals. (rsc.org)
- Benzene is not an ingredient in any of Bayer Consumer Health products. (fda.gov)
- Table 2 shows the results of the follow-up samples for the two products which were above the 10 ppb WHO benzene limit in drinking water. (fsai.ie)
- Sadly, now that benzene has contaminated products, health issues & adverse health consequences may arise. (mamavation.com)
- These products were tested at an ISO accredited laboratory for benzene and came up with detectable results. (mamavation.com)
Signs and symptoms2
Humans1
- The Department of Health and Human Services (DHHS) has determined that benzene causes cancer in humans. (cdc.gov)
Drinks2
- Benzene may form in drinks through a reaction between two common ingredients, benzoate preservatives and citric or ascorbic acid (vitamin C). Exposing drinks to heat increases the reaction. (foodnavigator-usa.com)
- The new guide also tells companies to test drinks for benzene after heat exposure, and asks them to consider whether they could remove one or more of the troublesome ingredients. (foodnavigator-usa.com)
Water5
- Benzene can pass into the air from water and soil. (cdc.gov)
- Benzene also can be absorbed into the body by eating food or drinking water or other beverages contaminated with benzene. (cdc.gov)
- Benzene dissolves only slightly in water and will float on top of water. (cdc.gov)
- To protect against cancer risks, California set a public health goal for benzene in drinking water at 0.15 parts per billion, 30 times lower than the federal legal limit of 5 parts per billion. (ewg.org)
- The EWG Health Guideline of 0.15 ppb for benzene was defined by the California Office of Environmental Health Hazard Assessment as a public health goal, the level of a drinking water contaminant that does not pose a significant health risk. (ewg.org)
Cigarette3
- Benzene is also present in cigarette smoke. (cdc.gov)
- Benzene, benzo(a)pyrene (BaP), and lead in mainstream smoke from cigars, roll-your-own (RYO) cigarette and pipe tobaccos were sampled to evaluate their potential health significance. (nih.gov)
- for benzene, the mean values for cigars, RYO cigarette and pipe tobaccos were 156 +/- 52, 68 +/- 11, and 242 +/- 126 micrograms/g, respectively. (nih.gov)
Indoor air1
- Health Canada wants your feedback on the proposed Residential Indoor Air Quality Guidelines (RIAQG) for Benzene. (canada.ca)
Tobacco smoke1
- A major source of benzene exposure is tobacco smoke. (cdc.gov)