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)
A form of pneumoconiosis resulting from inhalation of dust containing crystalline form of SILICON DIOXIDE, usually in the form of quartz. Amorphous silica is relatively nontoxic.
An interactive process whereby members of a community are concerned for the equality and rights of all.
The exposure to potentially harmful chemical, physical, or biological agents that occurs as a result of one's occupation.
The repetitive uterine contraction during childbirth which is associated with the progressive dilation of the uterine cervix (CERVIX UTERI). Successful labor results in the expulsion of the FETUS and PLACENTA. Obstetric labor can be spontaneous or induced (LABOR, INDUCED).
Artificially induced UTERINE CONTRACTION. Generally, LABOR, OBSTETRIC is induced with the intent to cause delivery of the fetus and termination of pregnancy.
A course or method of action selected, usually by a government, from among alternatives to guide and determine present and future decisions.
A diffuse parenchymal lung disease caused by inhalation of dust and by tissue reaction to their presence. These inorganic, organic, particulate, or vaporized matters usually are inhaled by workers in their occupational environment, leading to the various forms (ASBESTOSIS; BYSSINOSIS; and others). Similar air pollution can also have deleterious effects on the general population.
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.
Board members of an institution or organization who are entrusted with the administering of funds and the directing of policy.
An agency of the PUBLIC HEALTH SERVICE concerned with the overall planning, promoting, and administering of programs pertaining to maintaining standards of quality of foods, drugs, therapeutic devices, etc.
Freedom of equipment from actual or potential hazards.
Process that is gone through in order for a device to receive approval by a government regulatory agency. This includes any required preclinical or clinical testing, review, submission, and evaluation of the applications and test results, and post-marketing surveillance. It is not restricted to FDA.
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.
Swelling of the OPTIC DISK, usually in association with increased intracranial pressure, characterized by hyperemia, blurring of the disk margins, microhemorrhages, blind spot enlargement, and engorgement of retinal veins. Chronic papilledema may cause OPTIC ATROPHY and visual loss. (Miller et al., Clinical Neuro-Ophthalmology, 4th ed, p175)
Manometric pressure of the CEREBROSPINAL FLUID as measured by lumbar, cerebroventricular, or cisternal puncture. Within the cranial cavity it is called INTRACRANIAL PRESSURE.
A localized defect in the visual field bordered by an area of normal vision. This occurs with a variety of EYE DISEASES (e.g., RETINAL DISEASES and GLAUCOMA); OPTIC NERVE DISEASES, and other conditions.
Refraction of LIGHT effected by the media of the EYE.
Works containing information articles on subjects in every field of knowledge, usually arranged in alphabetical order, or a similar work limited to a special field or subject. (From The ALA Glossary of Library and Information Science, 1983)
Clarity or sharpness of OCULAR VISION or the ability of the eye to see fine details. Visual acuity depends on the functions of RETINA, neuronal transmission, and the interpretative ability of the brain. Normal visual acuity is expressed as 20/20 indicating that one can see at 20 feet what should normally be seen at that distance. Visual acuity can also be influenced by brightness, color, and contrast.
A refractive error in which rays of light entering the eye parallel to the optic axis are brought to a focus behind the retina, as a result of the eyeball being too short from front to back. It is also called farsightedness because the near point is more distant than it is in emmetropia with an equal amplitude of accommodation. (Dorland, 27th ed)
Food processed and manufactured for the nutritional health of children in their first year of life.
Parliamentary democracy located between France on the northeast and Portugual on the west and bordered by the Atlantic Ocean and the Mediterranean Sea.
A food group comprised of EDIBLE PLANTS or their parts.
An enzyme that catalyzes the oxidation of nitrite to nitrate. It is a cytochrome protein that contains IRON and MOLYBDENUM.
A plant species of the genus CITRUS, family RUTACEAE that provides the familiar orange fruit which is also a source of orange oil.
Inorganic or organic salts and esters of nitric acid. These compounds contain the NO3- radical.
Hospital department providing dental care.
A purely physical condition which exists within any material because of strain or deformation by external forces or by non-uniform thermal expansion; expressed quantitatively in units of force per unit area.
SNARE binding proteins that facilitate the ATP hydrolysis-driven dissociation of the SNARE complex. They are required for the binding of N-ETHYLMALEIMIDE-SENSITIVE PROTEIN (NSF) to the SNARE complex which also stimulates the ATPASE activity of NSF. They are unrelated structurally to SNAP-25 PROTEIN.
Authoritative treatises on drugs and preparations, their description, formulation, analytic composition, physical constants, main chemical properties used in identification, standards for strength, purity, and dosage, chemical tests for determining identity and purity, etc. They are usually published under governmental jurisdiction (e.g., USP, the United States Pharmacopoeia; BP, British Pharmacopoeia; P. Helv., the Swiss Pharmacopoeia). They differ from FORMULARIES in that they are far more complete: formularies tend to be mere listings of formulas and prescriptions.
Debris resulting from a process that is of no further use to the system producing it. The concept includes materials discharged from or stored in a system in inert form as a by-product of vital activities. (From Webster's New Collegiate Dictionary, 1981)
Disposal, processing, controlling, recycling, and reusing the solid, liquid, and gaseous wastes of plants, animals, humans, and other organisms. It includes control within a closed ecological system to maintain a habitable environment.
Worthless, damaged, defective, superfluous or effluent material from industrial operations.
Blood, mucus, tissue removed at surgery or autopsy, soiled surgical dressings, and other materials requiring special disposal procedures.
Clinical and laboratory techniques used to enhance fertility in humans and animals.
Substances that are energetically unstable and can produce a sudden expansion of the material, called an explosion, which is accompanied by heat, pressure and noise. Other things which have been described as explosive that are not included here are explosive action of laser heating, human performance, sudden epidemiological outbreaks, or fast cell growth.
CHILDBIRTH at the end of a normal duration of PREGNANCY, between 37 to 40 weeks of gestation or about 280 days from the first day of the mother's last menstrual period.
A naturally radioactive element with atomic symbol Rn, atomic number 86, and atomic weight 222. It is a member of the noble gas family found in soil, and is released during the decay of radium.
The science of controlling or modifying those conditions, influences, or forces surrounding man which relate to promoting, establishing, and maintaining health.