Mortality among pyrite miners with low-level exposure to radon daughters.

Abstract

A cohort mortality study was conducted with regard to a pyrite mine located in central Italy. Exposure to radon ranged form 0.12 to 0.36 working levels (WL) in the work areas; most measurements were around 0.2 WL. The concentration of free silica in the dust was less than 2%. The cohort was determined from company files and included 1 899 subjects. Mortality was studied for the years 1965-1983. The loss of to follow-up was less than 2%. The standardized mortality ratio for all causes and all neoplasms was 97 and 107, respectively. That for lung cancer and for nonmalignant respiratory diseases was 131 (95% confidence interval 97-175) and 173 (95% confidence interval 135-231), respectively. It was estimated that the extra cases of lung cancer attributable to radon daughter numbered 13 per 106 person-years and working level month in the whole cohort and 21.3 per 106 person-years in the subcohort with 10-25 yers of exposure.