Abstract:Organochlorine pesticides such as DDT and HCH were used extensively in China from the 1950s to the 1980s. Although their use was banned in 1983, their residua in soil are still detectable in many regions today. Pesticides should be generally toxic only to the target organisms. However, this is rarely the case. Some microbial groups are able to use an applied pesticide as a source of energy and nutrients, whereas the pesticide may be toxic to other microbial organisms. Because microbial groups react differen...