DDT (1,1,1-Trichloro-2,2-bis[ p-chloropheny1] ethane) 
DDD (TDE, Rhothane) (1,1-Dichloro-2,2-bis[chlorophenyl] ethane) 
Kelthane (1,1-bis[p-chlorophenyl] -2,2,2-trichloroethanol) 
Detoxification has long been considered a major factor in the 
defense of insects against the lethal action of DDT. This concept was 
strengthened by the isolation of DDT-dehydrochlorinase, a glutathione 
dependent enzyme (Lipke and Kearns, 1959, 1960; Miyake et al., 1957; 
Sternberg et al., 1954). In many insects this system catalyzed the 
degradation of p,p'’-DDT to p,p'-DDE or the degradation of p,p'-DDD to its 
corresponding ethylene derivative (Abedi et al., 1963; Babers and Pratt, 
1953a; Babers and Roan, 1953; Bull and Adkisson, 1963; Lindquist et al., 
1951; Perry et al., 1950, 195la, b, 1953a, b, 1955; Sternberg et al., 
1952a, b, 1950a, b, 1953; Tahori and Hoskins, 1953; Schecter, 1945; Lipke 
and Chalkley, 1964; Brown and Perry, 1956; Fletcher, 1952; Hoffman and 
Lindquist, 1952; Ofnmer and Calvery, 1945). o,p*DDT was not degraded. 
An alternate biotransformation in the fruit fly (Drosophila melano- 
gaster) gave rise to the hydroxy analog of DDT (Tsukamoto, 1959, 1960, 
1961; Menzel et al., 1961). Similarly, tobacco hornworm and the cockroach 
degraded TDE to its hydroxy analog (Gatterdam et al., 1964). It was also 
found that topically applied DDA was rapidly converted to several uniden- 
tified compounds by the hornwomm and the milkweed bug (Ferguson and Kearns, 
1949). In cockroach tissue, some TDEE was found after exposure to TDE 
but the major metabolite was 4,4'-dichlorobenzophenone (Gatterdam et al., 
1964). This compound has also been identified in tissues of insects 
exposed to DDT. When third-instar larvae of Triatoma infestans were 
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