MBC residues rapidly diminished in soil during solarization when compared to non-solarized control. MBC degradation during solarization is characterized by a shortening of the lag phase before the main degradation event. Similar, though less pronounced, dissipation of TBZ was also observed. An increased microbial activity potential was observed in soil exposed to elevated temperatures. Dissipation of MBC from soil is evident during the first 2 weeks of solarization even when soil is sterilized before polyethylene mulching, indicating the possible involvement of abiotic mechanisms in the dissipation process, apart from microbial activity. MBC had only a slight inhibitory effect on microbial activity in soil, as expressed by fluorescein diacetate hydrolysis. A more rapid dissipation of MBC was also obtained in modified Wisconsin temperature tanks which proved a reliable simulation system for studying soil solarization. Soil solarization significantly decreased bacterial and fungal colony forming units yet did not affect the number of actinomycetes. The use of solarization for decontamination of pesticide residues is suggested.