Occupational exposure indicators

EGBE is of low to moderate acute toxicity in humans. Clinical tests and reports from occupational exposures indicate EGBE is an irritant when inhaled. EGBE is considered a skin absorber, with the... 

Although human data regarding acute-duration inhalation and dermal exposure are not available, data from intermediate-duration occupational exposure indicate that effects related to uncoupling of oxidative phosphorylation and gastrointestinal effects probably are not route-specific. Acute-duration inhalation and dermal studies in animals could be conducted to determine dose-response relationships for these routes. 

Skender L, Karacic V, Prpic-Majic D. 1987. Occupational exposure indicators to tetrachloroethylene in a dry cleaning shop. In Occu Environ Chem Hazard Proc Int Symp, Biochem Cell Indices Hum Toxic Occup Environ Med 192 6. 

The effects of occupational exposure to lindane have been investigated extensively (96—100). These studies indicated that occupational exposure to lindane resulted in increased body burdens of this chemical however, toxic effects associated with these exposures were minimal and no central nervous system disorders were observed. This is in contrast to the polyneuropathies that are often observed after exposure to other haloorganic solvents. 

In the future, the preventive tole of toxicology will be emphasized. It will be increasingly important to develop early indicators to monitor longterm subtle exposures that predict deleterious effects that are known to have a causal relationship with occupational exposures. In addition to collection of blood and urine samples, also collection of cells from points of... 

An indicative limit value is a more common type of limit that reflects expert evaluation based on scientific data where it is possible to identify the highest level of exposure along with the corresponding reference time period for which one can have confidence that there will be no adverse effects on health. For any chemical agent for which an indicative occupational exposure limit value is established at the community level, member states shall establish a national occupational exposure limit value, taking into account the community limit value and determining its nature in accordance with national legislation and practice. 

In a case-control study of the relation between occupational exposures to various suspected estrogenic chemicals and the occurrence of breast cancer, the breast cancer odds ratio (OR) was not elevated above unity (OR=0.8 95% 01=0.2-3.2) for occupational exposure to endosulfan compared to unexposed controls (Aschengrau et al. 1998) however, the sample sizes were very small (three exposed seven not exposed), and co-exposure to other unreported chemicals also reportedly occurred. Both of these factors may have contributed to the high degree of uncertainty in the OR indicated by the wide confidence interval. 

Gastrointestinal Effects. Case reports indicate that acute inhalation exposure to trichloroethylene results in nausea and vomiting (Buxton and Hayward 1967 Clearfield 1970 David et al. 1989 DeFalque 1961 Gutch et al. 1965 Milby 1968). Anorexia, nausea, vomiting, and intolerance to fatty foods have also been reported after chronic occupational exposure to trichloroethylene (El Ghawabi et al. 1973 Schattner and Malnick 1990 Smith 1966). Trichloroethylene-induced efiects on the autonomic nervous system may contribute to these effects (Grandjean et al. 1955). Some of the people exposed to trichloroethylene and other chlorinated... 

The approach to developing metrics for process safety is analogous to those that might be used to assess Occupational Exposure risk. One can cite as well several indices that have been developed as metrics for estimating and ranking the safety of a given process or chemical reaction, such as the DOW fire and explosion index,the Stoessel index ° for hazard assessment and classification of chemical reactions, the Inherent Safety Index, the Prototype Index for Inherent Safety, amongst others. ... 

ACGIH maintains annual editions of the TLVs and BEIs which are used worldwide as a guide for evaluation and control of workplace exposures to chemical substances and physical agents. Threshold Limit Value (TLV ) occupational exposure guidelines are recommended for more than 700 chemical substances and physical agents. There are more than 50 Biological Exposure Indices (BEIs ) that cover more than 80 chemical substances. 

The usefulness of urinary thiosulfate as an indicator of nonfatal hydrogen sulfide toxicity has been studied (Kangas and Savolainen 1987). Urinary samples for thiosulfate were obtained from volunteers exposed by inhalation to 8, 18, or 30 ppm of hydrogen sulfide for 30-45 minutes (the occupational exposure limit of 10 ppm for 8 hours was never exceeded). Excretion of urinary thiosulfate increased linearly up to 15 hours postexposure. Beyond 15 hours, the urinary thiosulfate concentration remained low, possibly indicating that most of the absorbed hydrogen sulfide was metabolized or excreted within 15 hours. 

Pyrethroid insecticides are rapidly metabolized to their inactive acids and alcohol components, which are excreted primarily in urine. A small portion of the absorbed compounds is excreted unchanged. Occupational exposure to pyrethroid insecticides can be assessed by measuring intact compounds or their metabolites in urine. Biological indicators of internal dose in exposed subjects are reported in Table 7. Due to their rapid metabolism, determination of blood concentrations can only be used to reveal recent high-level exposures. 

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