Residues of some chlorinated hydrocarbon pesticides in rain water, soil and ground water, and their influence on some soil microorganisms

Abstract

Residues of lindane, heptachlor, heptachlor epoxide, aldrin, endrin, dieldrin, and DDT were monitored in rain water, the soil profile, and ground water. Heptachlor and heptachlor epoxide were detected in rain water in 1995 and 1996. The total concentrations of organochlorine detected were 4.7 and 10.6 μg L −1 for 1995 and 1996, respectively. Top soil showed a wider spectrum and higher concentrations of organochlorines detected. The total concentration detected in top soil was 9.5 μg kg −1, while concentrations detected at 50 cm depth mounted to 8 μg kg −1. Samples collected at 1 m depth had no detectable concentrations of any compound. Residues detected in ground water were higher than residues reported in many European countries. Residues detected in top soil and rain water caused a significant depression in soil heterotrophic bacteria and fungi. They also caused a sharp decrease in nitrifying bacteria.