Development, use, and availability of a job exposure matrix based on national occupational hazard survey data.

A job exposure matrix has been developed based on potential exposure data collected during the 1972-1974 National Occupational Hazard Survey (NOHS). The survey sample was representative of all U.S. non-agricultural businesses covered under the Occupational Safety and Health Act of 1970 and employing eight or more employees. Potential worker exposure to all chemical, physical, or biological agents was recorded during the field survey if certain minimum guidelines for exposure were met. The job exposure matrix (JEM) itself is a computerized database that assists the user in determining potential chemical or physical exposures in occupational settings. We describe the structure and possible uses of the job exposure matrix. In one example, potential occupational exposures to elemental lead were grouped by industry and occupation. In a second example, the matrix was used to determine exposure classifications in a hypothetical case-control study. Present availability as well as future enhancements of the job exposure matrix are described.

National estimates of occupational exposure to animal bladder tumorigens.

A prevention program for occupational bladder cancer should be based on an estimate of the number of workers previously and currently exposed to bladder carcinogens. The National Occupational Exposure Survey (NOES), which identified potential occupational exposures in approximately 5000 private sector firms in 1981 to 1983, is the best available source for recent hazard estimates; the National Occupational Hazard Survey (NOHS), conducted in 1972 and 1974, for past exposure estimates. The National Institute for Occupational Safety and Health Registry of Toxic Effects of Chemical Substances (RTECS) identified nearly 200 substances associated with animal bladder tumors. From NOES and NOHS, the numbers of workers with full time (greater than or equal to 4 hours/day) or any potential occupational exposure were estimated for the United States. About 60,000 workers were potentially exposed in the early 1970s and about 700,000 in the early 1980s on a full-time basis to the compounds on the RTECS list also appearing in NOES, and about 1.8 million workers in the 1970s and almost 3.5 million in the 1980s had some occupational exposure. Because matches were not found for many compounds and because NOES covers only part of the US work force, these are probably underestimates. The estimates for the number of exposed workers do not imply that these workers all have increased risk of developing bladder cancer, because some animal tumorigens may not be human carcinogens and our estimates are based on potential rather than measured exposures. The risk would depend on the potency, duration, and intensity of the actual exposures. Nevertheless these estimates are useful in estimating the approximate magnitude of the potential occupational exposure to animal bladder tumorigens.

Compliance with OSHA record-keeping requirements.

The Occupational Safety and Health Act of 1970 requires employers to maintain records of workplace injuries and illnesses. To assess compliance with the law, data from the National Occupational Exposure Survey (NOES) were examined. Of the 4,185 companies with 11 or more employees, 75 per cent maintained OSHA Form 200 designed for recording illnesses and injuries. The number of employees and the presence of a union were positive determinants in the record maintenance. Of companies with 500 or more employees, 95 per cent kept records compared with 60 per cent of companies with between 11 and 99 employees.

The prevalence of screening in industry: report from the National Institute for Occupational Safety and Health National Occupational Hazard Survey.

Data from 4,500 workplaces surveyed by the National Institute for Occupational Safety and Health (NIOSH) in the National Occupational Hazard Survey (1972 to 1974) and National Occupational Exposure Survey (1981 to 1983) show an increase in both preplacement and periodic medical screening in US industries during the past decade. The distribution of screening is primarily related to plant size, but also varies considerably by industry type; further, plants with industrial hygiene and safety programs and/or unions are more likely to provide screening examinations than those without, irrespective of plant size. As for workers potentially exposed to selected chemical hazards, the first survey provides no consistent evidence that such workers were more likely to receive exposure-specific tests than other workers. The significance of these findings is discussed in the context of the proposed framework for medical screening practices developed by NIOSH researchers.