Mortality study update of ethylene oxide workers in chemical manufacturing: a 15 year update.

Abstract

To investigate the long-term mortality patterns of workers with past exposure to ethylene oxide (EO). We redefined and updated a cohort of male workers employed in industrial facilities where EO was produced or used. All 2063 men were employed between 1940 and the end of 1988 and were observed for mortality through 2003. Cause specific Standardized Mortality Ratios were calculated. Internal analyses were made by applying Cox proportional hazards models to the data. No indications were found for excess cancer risks from EO exposures, including the lymphohematopoietic malignancies. There were 11 leukemia deaths and 11.8 expected and 12 non-Hodgkin lymphoma deaths and 11.5 expected. Proportional hazards modeling for all cause, leukemia and lymphoid malignancies mortality revealed no trends or associations with cumulative exposure. Despite the relatively high EO exposures in the past and extensive mortality follow-up, the cause specific mortality rates are comparable with those of the general US population. The Standardized Mortality Ratio analyses and the proportional hazards modeling for all cause mortality, leukemia and lymphoid malignancies mortality do not indicate exposure related effects in this cohort.