Employment status and effect of coal-mine dust exposure.
Am J Epidemiol 1995 Jun; 141(11)(Suppl):S68
The purpose of this study was to determine if coal miners who quit the profession suffer greater declines in pulmonary function associated with coal mine dust exposure than miners who continue working or are laid off. The subjects were 1829 white male coal miners who were participants in the National Study of Coal Workers' Pneumoconiosis and had been tested at two surveys an average of 15.1 years apart. At the initial survey, all subjects were active coal miners with an average of 10.8 years mining. By the final survey, 379 (21 %) had quit for a variety of reasons (e.g. sickness, injury, another job) and the remaining 1450 were either still mining (938) or laid off (512). Least squares linear regression was used to model the average annual change in the forced expiratory volume in one second (FEV1) from the initial to the final testing. The change in FEVI (milliliters/year, or ml/yr) associated with the mean inter-survey coal mine dust exposure (milligrams/meter3, or mg/m3) was negative for those who quit (-5.9 ml/yr per mg/m3, standard error (se=3.5, p=0.09) and slightly positive for those who kept on mining or were laid off (+2.6 ml/yr per mg/m3, se=1.8, p=0.15). The difference in effect was -8.5 ml/yr per mg/m3 (se=3.90, p=0.03). This finding suggests that miners who quit have a greater adverse response to coal mine dust exposure.
Biological-effects; Biological-factors; Biological-monitoring; Biological-systems; Coal-dust; Coal-miners; Coal-mining; Coal-processing; Coal-workers; Coal-workers-pneumoconiosis; Dust-exposure; Dust-inhalation; Exposure-assessment; Exposure-levels; Exposure-methods; Occupational-exposure; Occupational-hazards; Occupational-health; Respiratory-irritants; Risk-factors; Work-analysis; Work-areas; Work-environment; Worker-health; Work-operations; Work-practices; Work-operations; Workplace-studies
National Institute for Occupational Safety and Health, Centers for Disease Control and Prevention, Division of Respiratory Disease Studies, 1095 Willowdale Road, Morgantown, WV 26505
American Journal of Epidemiology. Abstracts of the 28th Annual Meeting of the Society for Epidemiologic Research, Snowbird, Utah, June 21-24, 1995