Relationship between cancer mortality and environmental cadmium exposure in the general Japanese population in cadmium non-polluted areas

The aim of the present study was to evaluate the effect of environmental cadmium (Cd) exposure indicated by urinary Cd (U-Cd) on cancer mortality in the general Japanese population. A 19-year cohort study was conducted in 1107 men and 1697 women who lived in three Cd non-polluted areas in Japan. Mortality risk ratio and 95% confidence interval (95%CI) for continuous U-Cd were estimated for all malignant neoplasms and specific cancers using a Fine and Gray competing risks regression model. The all-cause, including cancer and non-cancer mortality rates per 1000 person-years were 29.8 and 13.9 in men and women, respectively. By using Fine and Gray's method, continuous U-Cd adjusted for creatinine (+ 1 mu g/g cre) was significantly related to mortalities for all malignant neoplasms (risk ratio = 1.06, 95%CI: 1.02-1.11) and pancreas (risk ratio = 1.13, 95%CI: 1.03-1.24) in women. In the present study, U-Cd was significantly associated with increased cancer mortality in the general Japanese population, indicating that environmental Cd exposure adversely affects the life prognosis in Cd non-polluted areas in Japan.