Mortality of workers exposed to dieldrin and aldrin: a retrospective cohort study

Objective-To investigate the occurrence of long term health effects in humans exposed to aldrin and dieldrin, with an update of an earlier retrospective cohort mortality study. Methods-A group of 570 workers employed between 1 January 1954 and 1 January 1970 either in a production or formulation plant were followed up for mortality until 1 January 1993. There were extensive industrial hygiene data available and biological monitoring data of aldrin and dieldrin for most of the workers. From these data individual estimates were made of the total intake of dieldrin. A total number of 2539.37 person-years at risk was added to the original study. Results-118 deaths were observed compared with 156 expected. No increase in mortality from liver cancer was found. However, there was an excess in mortality from rectal cancer. This excess was inversely related to the dose gradient. An analysis by job title did not show any excess cancer in any particular job. Conclusion-The study does not support a carcinogenic effect of dieldrin and aldrin in humans.