Retrospective cohort mortality study of workers with potential exposure to epichlorohydrin and allyl chloride

Previous epidemiologic research has associated potential epichlorohydrin exposure with lung cancer and, in conjunction with allyl chloride exposure, to heart disease mortality. The study was designed to test both hypotheses by examining the mortality experience of 1,064 male employees (12,574 person-years) who had a minimum of 1 month work experience between 1957-1986 in the production or use of epichlorohydrin and allyl chloride and 1 year total employment duration at Dow Chemical's Texas Operations. Vital status follow-up occurred through 1989 of which there were 66 total deaths (standardized mortality ratio [SMR] = 80, 95% confidence interval [CI] 62-101). There were no significantly elevated SMRs for all malignant neoplasms, lung cancer, circulatory system disease, or arteriosclerotic heart disease when compared to external (U.S.) or internal (Texas Operations) populations. There were no apparent mortality trends with cumulative exposure analyses of potential epichlorohydrin exposure with and without accompanying allyl chloride exposure. A high prevalence of circulatory system death certificates were certified by nonphysicians in the local county and more than one third were described in nonspecific terms. The study results are not consistent with the prior hypothesized associations. However, the study results are limited by the cohort's size, duration of follow-up, relatively few number of observed and expected deaths, and the level of potential epichlorohydrin exposure experience.