Mortality among three refinery/petrochemical plant cohorts. II. Retirees

This study updates mortality data for 6238 retirees from three refinery/petrochemical plants. Almost 90% of the cohort was deceased. Deaths from all causes (standardized mortality ratio, 104; 95% confidence interval, 102 to 107) and all cancers (standardized mortality ratio, 109; 95% confidence interval, 102 to 116) were elevated. Increased deaths due to kidney cancer, mesothelioma, and the category of other lymphohemopoietic cancers also were observed. The rate of leukemia was not increased. There was little internal or external consistency to support an occupational relationship for kidney cancer, but findings for mesothelioma and other lymphohemopoietic cancers are consistent with reports for other petroleum cohorts. Analyses by age indicated significantly higher all-cause mortality rates among persons retiring before age 65. The results suggest that continued surveillance of mesothelioma and lymphohemopoietic cancer malignancies in younger workers with more contemporary exposures may be warranted. Furthermore, age at retirement should be considered when analyzing occupational cohorts.