Reduced dietary cadmium intake in past 12 years in a rural area in Japan.

To examine possible reduction in dietary cadmium (Cd) intake, 24-h duplicates of diet were collected twice in the same village in north-eastern Japan, once in 1976-1977 (71 samples) and then in 1989 (198 samples) and analyzed for Cd contents. The statistical analysis by sex and age decade showed that there has been a significant (P less than 0.01-0.05, depending on sex and age) reduction in Cd intake during this 12-year period. The intake by men at 30-59 years was 28.8 micrograms/day (as a geometric mean of 41 samples) in 1976-1977 and 20.8 micrograms/day in 1989, indicating some 28% reduction, whereas the value for women of the same age range was 24.9 micrograms/day in 1976-1977 and 15.7 micrograms/day in 1989, with a reduction by 37%. A similar reduction in Cd contents was observed in cooked rice samples collected in 1980 and 1990 in the vicinity of the study field. Probable reasons for the improvement are discussed.