Organochlorine insectide residues in vegetables of the Kitakyushu District, Japan--1971-74.

The residue levels of organochlorine insecticides BHC, DDT, endrin, and dieldrin in the Kitakyushu District, Japan, were monitored from 1971 to 1974. Agricultural uses of these insecticides were banned in 1970. BHC isomers, alpha, beta, gamma, and delta-BHC were detected in all vegetable samples taken; beta-BHC residue appeared in the highest levels. The proportions of each BHC isomer in total BHC residues were much different from those in the technical product. Average residue levels of alpha, beta, gamma, and delta-BHC, dieldrin, endrin, and DDTR (p,p'-DDE+p,p'-TDE+o,p'-DDT) in 1971 were 0.007, 0.042, 0.010, 0.008, 0.021, 0.010, and 0.041 ppm in radishes, and 0.004, 0.007, 0.009, 0.003, 0.087, 0.031, and 0.009 ppm in cucumbers. Levels found in 1974 were 0.002, 0.003, less than 0.001, less than 0.001, 0.005, 0.006, and less than 0.001 ppm in radishes, and less than 0.001, 0.001, 0.001, less than 0.001, 0.008, 0.009, and undetectable in cucumbers. These residues were translocated form the insecticide-contaminated field soils to the vegetables through therir roots. Residue levels of dieldrin and endrin frequently exceeded the pesticide tolerance limits of Japan, but DDTR residues were only slightly above the specified levels.