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Equilibrium phase distribution coefficients are used to describe the degree of transfer from inhaled air to blood, or from blood to exhaled air in models of solvent pharmacokinetics such as are used for toxicological assessment pruposes. A review of the literature shows examples of interexperimental blood/air partition coefficient values for specific solvents that very by a factor of 2.5.

Low levels of a variety of N-nitroso (NNO) compounds are present throughout the modern human environment with exposure occuring from food, water, air, tobacco usage and industrial and consumer products. These compounds are also formed endogenously in reactions mediated by bacteria and macrophages.

Toxicant exposure beneath some threshold level is often considered to pose little risk of producing any adverse effect. However, exposure to multiple toxicants, each beneath the level of concern, can lead to toxicity through a synergistic or additive action. This toxic integration can arise when the toxicants target the same tissue or organ.

Ozone is a ubiquitous secondary atmospheric air pollutant frequently measured in many urban areas at levels exceeding the National Ambient Air Quality Standard, currently 120 ppb averaged over a one hour period.

Ethanol is known to directly influence the developing nervous system, the neuronal membrane being a primary site of action. In recent years, it has been hypothesized that the muscarinic receptor-stimulated phosphoinositide (PI) metabolism may represent a relevant target for the developmental neurotoxicity of ethanol.

Breath sampling has been proposed as a non-invasive method of biological monitoring of workers exposed to organic solvents. To correct breath sampling variability, CO2 has been used as a normalizing factor. This method is based on the assumptions that individual alveolar CO2 concentrations are reasonably close to the normalizing factor used (i.e.

Isocyanates are widely used as hardeners in tw-component paints and in the production of plyurethane materials. Commercially available isocyanates exist as monomers, dimers or polymers. Exposure to isocyanates can cause respiratory problems and can induce asthma-like symptoms in sensitized individuals at low exposure levels.

Much of the research regarding organophosphorous insecticides in soil has focused on insecticide efficacy/degradation for agricultural production, potential groundwater leaching and the establishment of worker reentry levels.

Chlorinated organic compounds are a class of pollutants which have been released into the environment in large quantities from a multitude of sources. Because of their physical and chemical properties, these compounds possess sufficient mobility to reach groundwater and sediments.

Composting of municipal solid waste (MSW) is being investigated as an alternative to landfilling for the organic fraction of the waste stream. MSW is known to contain volatile organic compounds (VOCs) at concentrations as high as 0.1% by weight.

The effects of soil loading and organic carbon (OC) content on the uptake of contaminants in soil were examined using an in vitro evaporation/penetration apparatus with cadaveric human skin.

Intercellular communication through gap junctions (GJIC) is important in the control of cellular growth and differentiation and in many cellular processes including electrical synapsing, maintenance of homeostasis, hormonal response, and enbryonic development. The loss of intercellular communication may have numerous pathological consequences including teratogenesis and carcinogenesis.

Lead exposure is a major public health concern for the general population and for workers in a wide variety of occupations. Considering either cumulative or current production, the figures for lead vastly exceed those of any other inorganic human toxicants.

Objective--To determine whether patients suffering from Multiple Chemical Sensitivity Syndrome (MCS) show variations or abnormalities in immunologic parameters distinguishable from the results of similarly tested control subjects. Design---Case control comparison study.

Gamma-glutamylcysteine (g-GCS) synthetase is the rate-limiting enzyme in a two step pathway that synthesizes glutathione (GSH). Isolated from rate kidney, the g-GCS enzyme consists of two subunits which can be dissociated under denaturing or nondenaturing conditions. The heavy subunit displays all the catalytic activity of the isolated enzyme, as well as feedback inhibition by GSH.

The association between fire smoke exposure and pulmonary function was studied cross-sectionally among Seatttle firefighters participating in a voluntary medical surveillance program between 1988 and 1991.

Glutathione S-Transferases (GSTs) are a multi-gene family of enzymes which act in the detoxification of many environmentally and occupationally important carcinogens. Dietary items such as broccoli, brussels sprouts, onions and garlic are known to protect against cancer incidence; each of these vegetables contains compounds that increase GST levels.

The potential for high lead level exposure at indoor firing ranges has been recognized since the 1940s. Yet there have been occupational studies on lead exposures to employees and firing aRMS instructors at indoor firing ranges. These studies have been completed in the 1970s and 1980s consistently documented blood lead levels above 60 ug/dl as well as excessively high air lead levels.

This study evaluates occupational exposure to perchloroethylene (PCE) among commercial dry cleaning workers (n=72), typically in small businesses with fewer than 15 employees. No eligibility restrictions were imposed on volunteers according to sex or age; but, shops currently not using PCE were excluded.

Dermal contact with contaminated soils is a potential pathway for chemical exposure.

Statistics compiled by the National Safety Council (NSC) and the US Bureaur of Labor Statistics indicate that the construction industry is one of the most hazardous to work in. The annual accident data state that of the approximately 5.9 million workers in the construction industry there were 1,300 deaths and 300,000 disabling injuries in 1992.