Larvae of Culex tarsalis, Culex pipiens fatigans, Culex pipiens 
quinquefasciatus and Aedes aegypti metabolized DDT to DDE. Generally, 
some DDD was also produced. With C. fatigans, Aedes aegypti, and several 
strains of C.p. quinequefasciatus, the water extracts also contained a 
product that appeared to be the dehydrochlorinated product of DDD (386, 688, 
754, 793, 794, 1612, 1613, 1648). Other studies showed that the DDT- 
resistant mosquito Culex tarsalis Coquillett degraded TDE to DDA, bis(p- 
chlorophenyl) methanol (DBH) and p-chlorobenzoic acid (1169). 
Some studies indicated that metabolism of DDT might not always proceed 
through DDE. Using a DDT-resistant strain of the human body louse (1144), 
it was found that DDT was metabolized to a water-soluble compound that 
behaved like p-chlorobenzoic acid. In subsequent studies, DDT was metabolized 
to dichlorobenzophenone (DBP) via DDA or to DDE (1154). 
Enzyme fractions have been prepared from extractions of human body louse. 
These fractions indicated the existence of different native enzymes which 
produce different metabolites. Fraction A gave a 6:1 ratio of neutral to 
acidic metabolite. The neutral metabolite was predominantly DDE. Fraction 
B gave a 1:1 ratio of neutral to acidic metabolite. The neutral metabolite 
in this case was predominantly 4,4'-dichlorobenzophenone. The acidic meta- 
bolite produced by both enzyme fractions appeared to be DDA (1011). 
In the fruit fly, Drosophila melanogaster, the hydroxy analog of DDT 
(dicofol ) was formed (982, 1424, 1425, 1426). The lady bettle, Coleomegilla 
maculata de Geer, metabolized DDT essentially to DDE (41). 
The milkweed bug, Oncopeltus fasciatus (Dallas) stored unchanged DDT in 
its internal tissues and excreted it as such. Some water soluble oxidation 
products were indicated but not identified (1518). When DDA was applied 
topically, several unidentified compounds were formed (447). 
The Mexican bean beetle, Epilachna varivestis Muls, contained DDT- 
dehydrochorinase activity in its tissues and was able to dehydrochlorinate 
DDD (1411). When third-instar larvae of Triatoma infestans were topically 
treated with DDT-c!", two metabolites were detected, kelthane and a compound 
that behaved like 4,4'-dichlorobenzohydrol. The latter also appeared after 
topical treatment with kelthane (6). 
In the larvae of the tobacco budworm, Heliothis virescens (F.), the 
predominant product of DDT metabolism was DDE. However, DDA was also 
present (1449, 1450). The tobacco hornworm degraded TDE to its hydroxy 
analog (527). It was also found that topically applied DDA was rapidly 
converted to several unidentified compounds by the hornworm (447). 
DDT was metabolized to DDE by the desert locust (1344) and the Asian 
blood-sucking leech, H. nipponia (795). 
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