Lung cancer mortality among men living near an arsenic-emitting smelter.

Etiologic factors for lung cancer were studied by the case-control technique among 636 men, including 212 with pulmonary carcinoma, who had died between 1961 and 1979 in a county in northern Sweden. Data on smoking habits, occupation, and residence were obtained from a next of kin to each study subject. Validation against data from other sources indicated that the exposure information was of high quality. A relative risk of 2.0 for lung cancer was seen among men who had lived within approximately 20 km from a large copper smelter. The increased risk, which is statistically significant (p less than 0.05), could not be explained by smoking habits or occupational background. Smelter workers and miners had relative risks for lung cancer of 3.0 and 4.1, respectively. No firm conclusions can be drawn on the cause of excess lung cancer risk in the smelter area, but it seems plausible that the very substantial emissions to air from the smelter, especially of arsenic, may have played a role.