Mortality and cancer incidence in aluminum smelter workers: a 5-year update.

OBJECTIVE:To determine the mortality and cancer incidence of aluminum smelter workers. METHOD:The experience of 17,089 workers between 1950 and 2004 was studied. RESULTS:There were 25 deaths/47 female incident cancers and 6350 deaths/3984 male incident cancers. Mortality was significantly elevated for chronic obstructive pulmonary disease, Alzheimer disease (likely influenced by regional factors), all cancers, stomach, bladder, and lung cancers. Incidence was significantly elevated for bladder, lung, and laryngeal cancers. Digestive, lung, and bladder cancer mortality and lung, bladder, and buccal cancer incidence increased significantly with benzo(a)pyrene (B(a)P) exposure. Over time lung cancer risk has diminished but bladder cancer risk has not. CONCLUSIONS:Bladder cancer incidence was not increased at B(a)P exposures below 40 μg/m·yr. Occupational origins for other cancers occurring above expected rates but probably unrelated to B(a)P exposure cannot be excluded. In the prebake plant, nonsignificant increases of lung cancer were observed between 2000 and 2004.