Mortality among chemical workers exposed to benzene and other agents.

A historical cohort mortality study was conducted of 259 male employees of a chemical plant where benzene has been used in large quantities. The study group included all persons who were employed by the Company any time between January 1, 1947 and December 31, 1960. The cohort was followed through December 31, 1977 at which time 58 known deaths were identified. The only unusual finding was four deaths from lymphoreticular cancers when 1.1 would have been expected on the basis of national mortality rates. Three of the deaths were due to leukemia and one was caused by multiple myeloma. In addition, one of the leukemia deaths had multiple myeloma listed on the death certificate. The findings are consistent with previous reports of leukemia following occupational exposure to benzene and raise the possibility that multiple myeloma could be linked to benzene, also.