Occupational exposure and lung cancer risk: A population-based case-referent study in Sweden

This case-referent study investigated the lung cancer risk from occupationa l exposure to diesel exhaust, mixed motor exhaust, other combustion product s, asbestos, metals, oil mist, and welding fumes. All cases of lung cancer in males aged 40-75 years among stable residents of Stockholm County, Swede n, were identified from 1985 to 1990. Referents were selected as a stratifi ed (age, inclusion year) random sample. Information on lifetime occupationa l history, residency, and tobacco smoking was obtained from the study subje cts or from next of kin. Response rates of 87% and 85% resulted in 1,042 ca ses and 2,364 referents, respectively. Occupational exposures were assessed by an occupational hygienist who coded the intensity and probability of ea ch exposure. Risk estimates were adjusted for tobacco smoking, other occupa tional exposures, residential radon, and environmental exposure to traffic- related air pollution. For the highest quartile of cumulative exposure vers us no exposure, the relative risk was 1.63 (95% confidence interval (CI): 1 .14, 2.33) for diesel exhaust, 1.60 (95% Ct: 1.09, 2.34) for combustion pro ducts, and 1.68 (95%:. CI: 1.15, 2.46) for asbestos. Dose-response analyses indicated an increase in lung cancer risk of 14% per fiber-year/ml for asb estos exposure. No increased risk was found for the other exposure factors. An overall attributable proportion of 9.5% (95% Ct: 5.5, 13.9) was estimat ed for lung cancer related to diesel exhaust, other combustion products, an d asbestos.