“…Chlorinated hydrocarbon insecticides persist for several years in soils under nonflooded conditions (Edwards, 1972; Pionke and Chesters, 1973). In contrast, some of these chlorinated hydrocarbons such as benzene hexachloride (1,2,3,4,5,6-hexachlorocyclohexane), DDT (1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane), methoxychlor (l,l,l-trichloro-2,2-bis(p-methoxyphenyl)ethane), and heptachlor (l,4,5,6,7,8,8-heptachloro-3a,4,5,5a-tetrahydro-4,7-endo-methanoindene) readily break down in a predominantly anaerobic flooded soil ecosystem (Sethunathan, 1973a).…”