Mortality Among Rubber Workers III. Cause-Specific Mortality, 1940-1978

This report describes mortality occurring between 1940 and mid-1978 among 29,087 men and women employed in a rubber plant for at least two years. Mortality patterns for the period July 1, 1974, to July 1, 1978, were compared to previously published findings for January 1, 1940, through June 30, 1974. Expected numbers of deaths were based on U.S. general population mortality data. There were excess deaths from bladder cancer and leukemia among white male union members during both follow-up periods. During recent follow-up of white male union members employed for at least five years, there were excesses in deaths from three additional cancers: esophageal cancer (11 observed/4.8 expected), biliary and liver cancer (6 observed/3.3 expected) and lymphoma and multiple myeloma (14 observed/5.8 expected). Evidence from other studies of rubber workers suggests that observed excesses in deaths from bladder cancer and leukemia are related to work-place exposures. The present findings suggest that occupational exposures etiologically relevant to these diseases may not have been reduced in recent years or that sufficient time has not elapsed for such reductions to result in decreased mortality. Further investigation is required to clarify the contribution of occupational factors to observed excesses in deaths form cancers of the esophagus and the biliary passages and liver and from lymphoma and multiple myeloma.