Cancer mortality in a cohort of naval shipyard workers in Hawaii: early findings

A retrospective cohort study was performed in Hawaii among 4,779 male shipyard workers exposed to asbestos and 2,757 similar male workers without known asbestos exposure. Observed deaths from cancer and other causes in the 2 groups were compared with expected deaths on the basis of the general population of Hawaii by the use of a modified life-table method of analysis. A risk ratio for lung cancer of 1.7 was found for the exposed group after 20 or more years of follow-up. No increased risk for lung cancer was seen in the nonexposed group. These findings could not be attributed to differences in smoking habits in the 2 shipyard groups or between the shipyard groups and the general population. Because the maximum duration of follow-up for this analysis was 24 years, greater risks for lung cancer may be seen in the exposed group when the follow-up period is extended.