Morbidity prevalence study of workers with potential exposure to epichlorohydrin

This study examined the morbidity experience from 1981 to 1988 of two cohorts (Shell cohort and Enterline cohort) of workers who had potential exposure to epichlorohydrin (ECH). The morbidity prevalence data for this study were extracted from the morbidity section of the Shell health surveillance system which included all illness and absence records in excess of five days. For both cohorts, the standardised morbidity ratios (SMRs) for all causes and all neoplasms were similar to an internal comparison group. There were no increases in heart disease morbidity for the Shell cohort (SMR = 97) or the Enterline cohort (SMR = 90). The SMRs for heart disease in the lower exposure group of the Shell cohort were 101 and 93 for the corresponding Enterline cohort. They were 92 and 87, respectively, in the higher exposure group. The increased risk of heart disease mortality reported by Enterline et al in workers more heavily exposed to ECH was not confirmed in this morbidity study. Morbidity from skin and subcutaneous tissue disorders, however, was found to be increased significantly in the Shell cohort. The SMR was 98 for the lower exposure group and 195 for the higher exposure group. A review of the original morbidity reports for each case suggested that factors unrelated to exposure to ECH such as the physical demands of a particular job, amount of time outside--for example, exposure to poison ivy--and other underlying medical conditions may be of greater importance than exposure to ECH.