The purpose of this investigation was to grasp the actual state of the pollutions of fresh-water and marine fishes and shellfishes with organochlorine pesticides in Japan.
In the period of 18 months (August, 1969 to February, 1971), organochlorine pesticide residues in 101 samples of fishes and shellfishes collected in rivers, lakes and sea in Hokkaido, Niigata and Aichi prefectures were examined.
The levels on fresh weight of tissue in fresh-water and marine fishes and shellfishes were found in the ranges of 0.009 to 0.79ppm and 0.004 to 0.21ppm in total BHC residues, 0.014 to 0.87ppm and 0.002 to 0.15ppm in total DDT residues and 0.000 to 0.14ppm and 0.000 to 0.039ppm in dieldrin residues, respectively.
Compared with organochlorine pesticide residues in marine fishes, those in fresh-water fishes were higher, the levels of the latter were higher about 20 times in β-BHC residues, higher about 10 times in γ-BHC residues, higher about 15 times in total BHC residues, higher about 5 times in total DDT residues and higher about 7 times in dieldrin residues than those of the former.
