Cancer risk among Japanese chromium platers, 1976-2003.

OBJECTIVE

The aim of our prospective cohort study was to assess cancer mortality risks among chromium platers.

METHODS

The cohort comprised 1193 male platers (626 with exposure to chromium, the remainder with no exposure) with a follow-up period of 27 years (1 October 1976 to 31 December 2003). Mortality risk was assessed by the standardized mortality rate (SMR) with reference to the national population.

RESULTS

Lung cancer mortality was elevated only in the chromium plater subgroup, with borderline statistical significance [SMR=1.46, observations (Obs)=28, 95% confidence interval (95% CI) 0.98-2.04]. The chromium plater subgroup also showed elevated mortality risks for brain tumor (SMR=9.14, Obs=3, 95% CI 1.81-22.09) and malignant lymphoma (SMR=2.84, Obs=6, 95% CI 1.05-5.51). Risks were particularly elevated for lung cancer (SMR=1.59, Obs=23, 95% CI 1.01-2.38) and malignant lymphoma (SMR=3.80, Obs=6, 95% CI 1.39-8.29) among those with initial chromium exposure prior to 1970.

CONCLUSIONS

In Japan, occupational exposure to chromium through work as a chromium plater is a risk factor for lung cancer, especially for platers working prior to 1970. Occupational chromium exposure may also increase the risk of brain tumor and malignant lymphoma.