Respiratory Cancer and Occupational Exposure to Arsenicals

Abstract

The proportionate mortality experience of 173 decedents exposed primarily to lead arsenate and calcium arsenate was compared with that of 1,809 decedents not exposed to those compounds. A significant increase in respiratory cancer was found among the exposed employees. The relationship between cumulative arsenic exposure and the ratio of observed to expected respiratory malignancy deaths was estimated by means of a least squares approach. The predicted ratio was 7:1 for individuals exposed for a period of more than eight years to compounds that contained an equivalent level of 1 mg/cu m arsenic. In the more heavily exposed individuals, an excess of respiratory cancer was observed 35+ years after the initial exposure. Observations based on the proportionate study were supported by an analysis of the same target population, employing the prospective study in retrospect approach.