Mortality and cancer incidence in biomedical laboratory personnel in Sweden

Background: The work in biomedical laboratories is associated with exposure to a mixture of known and potential chemical carcinogens, mutagens, and te ratogens. Previous studies have suggested an excess of brain tumors and hem atopoietic system malignancies as well as breast cancers in women. Methods: This retrospective cohort study investigated the standardized mort ality ratio (SMR) and the standardized incidence ratio (SIR) for cancer in biomedical research laboratory personnel in Swedish universities 1970-1992. The cohort comprised 5,035 laboratory and, as an infernal reference group, 2,923 nonlaboratory employees. Results: The overall death rate was lower in both groups than in the genera l population. The SIR for brain tumors among male laboratory workers was 1. 69 (0.62-3.68) and among male laboratory scientists, after more than 10 yea rs of work (4 cases), it was 3.11 (0.85-7.56). There was an elevated SIR fo r malignant melanoma among female scientists in laboratories (3.51, 0.96-8. 98) and for male scientists in nonlaboratory departments (2.86 1.05-6.22). The SIR for breast cancer among female laboratory scientists was 1.62 (0.78 -2.98). Conclusions: The present findings lend some support to an excess of brain t umors among male scientists and of breast cancer in female scientists in bi omedical research laboratories. Am. J. Ind. Med. 35:382-389, 1999. (C) 1999 Wiley-Liss, Inc.