Ontario gold miners with lung cancer. Occupational exposure assessment in establishing work-relatedness.

Because of inherent errors in exposure data as well as a requirement in the Workers' Compensation Act of Ontario that all claims must be considered on the merits and justice of the individual case, the criteria for assessing work-relatedness of Ontario gold miners who had primary lung cancer could not be based upon any strict occupational exposure criteria. However, a relationship between exposure to silica, arsenic, and radon progeny was derived from results of the epidemiologic studies. A retrospective occupational exposure assessment of silica dust, arsenic, and radon decay products was made in individual cases presented in this paper. The assessment results of 11 gold miners presented in this paper illustrate that the exposure parameters could provide persuasive evidence when the data were consistent with the key epidemiologic findings, eg, the miner's age at first exposure, length of dusty exposure, and latency.