OBJECTIVE: The purpose of this data compilation is to overview past and current dietary exposure (primarily via rice) of general populations to cadmium (Cd) in environmentally polluted and non-polluted areas in Japan, and to compare the levels with counterpart levels in other areas in Asia. METHODS: A literature survey was conducted for publications on this subject, in either Japanese or international languages, since the early 1970s. Most of the studies identified employed the food-duplicate method in combination with atomic absorption spectrometry for Cd determination, although a few studies utilized other methods, such as the market basket method and dithizon-colorimetry. RESULTS: The highest estimate of dietary Cd intake (Cd-D), 600 microg Cd/day, was reported in the late 1960s for the local population in the Jinzu river basin, where Itai-itai disease had been endemic, and the Cd-D levels were 300 microg/day or higher in other polluted areas. Cd-D dropped to well below 100 microg/day when the polluted soil was replaced in the late 1970s and thereafter. In non-polluted areas, the Cd-D was reported to be approximately 100 microg/day in 1969, followed by a gradual decrease to approximately 40 microg/day in the late 1970s, to reach the current level of less than 30 microg/day. There is a trend of gradual reduction at the rate of 0.3 to 0.6 microg/day per year. Cd from rice accounted for 30 to 40% of the Cd-D in non-polluted areas, but a higher contribution was observed in some polluted areas. Nevertheless, the current Cd-D is still higher than the levels in other rice-dependent populations in east and south-east Asia. CONCLUSION: The Cd-D levels reported for polluted areas were in excess of 300 microg Cd/day. Substantial reduction in Cd-D to the level below 100 microg/day was observed after remediation, such as replacement of polluted paddy soil. In non-polluted areas, there has been a gradual decrease in Cd-D in the past 25 years. Nevertheless, the levels in the current intake of the general population in Japan (25 to 30 microg/day, or <1/10 of the levels in polluted areas in the past) is still higher than the levels in other rice-dependent areas in Asia.
OBJECTIVE: The purpose of this data compilation is to overview past and current dietary exposure (primarily via rice) of general populations to cadmium (Cd) in environmentally polluted and non-polluted areas in Japan, and to compare the levels with counterpart levels in other areas in Asia. METHODS: A literature survey was conducted for publications on this subject, in either Japanese or international languages, since the early 1970s. Most of the studies identified employed the food-duplicate method in combination with atomic absorption spectrometry for Cd determination, although a few studies utilized other methods, such as the market basket method and dithizon-colorimetry. RESULTS: The highest estimate of dietary Cd intake (Cd-D), 600 microg Cd/day, was reported in the late 1960s for the local population in the Jinzu river basin, where Itai-itai disease had been endemic, and the Cd-D levels were 300 microg/day or higher in other polluted areas. Cd-D dropped to well below 100 microg/day when the polluted soil was replaced in the late 1970s and thereafter. In non-polluted areas, the Cd-D was reported to be approximately 100 microg/day in 1969, followed by a gradual decrease to approximately 40 microg/day in the late 1970s, to reach the current level of less than 30 microg/day. There is a trend of gradual reduction at the rate of 0.3 to 0.6 microg/day per year. Cd from rice accounted for 30 to 40% of the Cd-D in non-polluted areas, but a higher contribution was observed in some polluted areas. Nevertheless, the current Cd-D is still higher than the levels in other rice-dependent populations in east and south-east Asia. CONCLUSION: The Cd-D levels reported for polluted areas were in excess of 300 microg Cd/day. Substantial reduction in Cd-D to the level below 100 microg/day was observed after remediation, such as replacement of polluted paddy soil. In non-polluted areas, there has been a gradual decrease in Cd-D in the past 25 years. Nevertheless, the levels in the current intake of the general population in Japan (25 to 30 microg/day, or <1/10 of the levels in polluted areas in the past) is still higher than the levels in other rice-dependent areas in Asia.
Authors: M Ikeda; Z W Zhang; S Shimbo; T Watanabe; H Nakatsuka; C S Moon; N Matsuda-Inoguchi; K Higashikawa Journal: Sci Total Environ Date: 2000-04-17 Impact factor: 7.963
Authors: T Watanabe; Z W Zhang; J B Qu; G F Xu; L H Song; J J Wang; S Shimbo; H Nakatsuka; K Higashikawa; M Ikeda Journal: Sci Total Environ Date: 1998-06-30 Impact factor: 7.963
Authors: M Ikeda; J Moriguchi; T Ezaki; Y Fukui; H Ukai; S Okamoto; S Shimbo; H Sakurai Journal: Int Arch Occup Environ Health Date: 2005-07-05 Impact factor: 3.015