PHYSICAL-CHEMICAL AND BIOLOGICAL DEGRADATION STUDIES ON DDT ANALOGS WITH ALTERED ALIPHATIC MOIETIES

A series of diethoxy 1,1,1-trichloro-2, 2-bis(p-chlorophenyl)ethane (DDT) analogues with eight different aliphatic moieties were subjected to photodegradation studies, utilizing a sterile soil, an aqueous solution, and a film on glass. The 2-chloroisobutane analogue, a tertiary chloride, was quite photolabile in all trials. Photolability followed the order of the ease of formation of free radicals by loss of chlorine from the aliphatic moiety: tertiary secondary primary-no chlorine. Several series of analogues were evaluated for biological degradation rates and products in the following types of studies: housefly synergistic ratios, housefly penetration-metabolism-excretion, salt marsh caterpillar metabolism, mouse metabolism, and in vitro metabolism by mouse liver microsomes. Both aliphatic and aromatic substituents influence biological degradation of the DDT analogues. In model ecosystem assessments of environmental fate, the two most important factors affecting bioaccumulation in fish were the type of alkyl chloride and water solubility of the molecule. © 1979, American Chemical Society. All rights reserved.