Investigation of an excess of melanoma among employees of the Lawrence Livermore National Laboratory.

As a follow-up to an observed fourfold excess of malignant melanoma among workers at Lawrence Livermore National Laboratory, Alameda County, California, the authors conducted a case-control interview study of 31 cases diagnosed during the period 1969-1980 and 110 individually matched controls. Respondents were queried regarding familial cancer history, health history, general health behaviors, socioeconomic status, sun-exposure history, skin sensitivity to sunlight, and detailed occupational and occupational exposure history. Measurements were taken of constitutional risk factors such as eye color and skin reflectance. The associations between nonoccupational risk factors and case status were consistent with those reported from population-based studies of malignant melanoma. Several occupational indicators of risk were strongly associated with case status. These included chemist duties (odds ratio (OR) = 8.0), as well as work around high explosives (OR = 3.0), volatile photographic chemicals (OR = 3.0), and sources of ionizing radiation (OR = 3.7). Multivariate analyses of these risk associations suggested each to have a reasonably independent relation to case status. After adjustment for constitutional and occupational risk factors of interest, the odds ratio associated with reported work around sources of ionizing radiation remained elevated (OR = 2.3, 95% confidence interval 1.0-7.6). The authors believe these results to be sufficiently suggestive to warrant additional studies of occupational factors and risk for malignant melanoma of the skin.