Case-control study of lung cancer in civilian employees at the Portsmouth Naval Shipyard, Kittery, Maine.
A case/control study of lung cancer in civilian employees at the Portsmouth Naval Shipyard (SIC-3731), Kittery, Maine, was conducted among white males who worked at the shipyard at any time from January 1, 1952, to August 15, 1977. There were 405 men identified as dying from lung cancer. Three comparisons were selected for each case, a total of 1,215 persons. Of the lung cancer cases, 121 had radiation histories, while 330 of the comparisons had radiation histories. An odds ratio of 1.23 was found for radiation exposure in lung cancer cases. When workers with cumulative lifetime radiation exposure of 1.00 to 4.999 rem were compared with those who had no history of radiation, a statistically significant odds ratio of 1.81 was found. Analyses of the effects of exposure to asbestos (1332214) and welding byproducts were conducted to evaluate whether radiation or a combination of occupational exposures was responsible for the odds ratio. A progressive increase in odds ratios was observed with increasing duration of exposure to asbestos. Occupational exposure to welding was associated with increased risk of lung cancer; the odds ratio for ever working in welding exposure was 1.46. Lung cancer odds ratios for asbestos and welding exposure were calculated; for such exposure the odds ratio was 1.43, while for a 5 year exposure the ratio was 1.50. Effects of latency were analyzed; odds ratios were not significant for exposure to any amount of radiation or at any lag period examined (5, 10, 15, and 20 years). The results did not support the possible relation between radiation exposure and lung cancer in workers at the Portsmouth Naval Shipyard.