Occupational and Environmental Medicine 1996;53:231-234 Incidence of cancer among Norwegian boiler welders

Objectives-The cancer incidence among 2957 boiler welders was investigated. The subjects were registered electrical welders from 1942 to 1981. A subcohort of 606 stainless steel welders was studied separately. Methods-The investigation was a historical prospective cohort study based on a national registry. The loss of follow up was 4 9%. Results-There were 625 deaths (659 expected). There were 269 cancer cases (264 expected). An excess of lung cancer was found; 50 cases v 37'5 expected. There were three cases ofpleural mesotheliomas v 1-1 expected. The subcohort of stainless steel welders had six cases oflung cancer v 5*8 expected, and one case of pleural mesothelioma v 0'2 expected. Conclusions-The welders in the study were assumed to represent a qualified work force. These welders had a small excess risk oflung cancer. The excess risk did not seem to be associated with stainless steel welding. Smoking and asbestos exposure were potential confounders. (Occup Environ Med 1996;53:231-234)