Epoxidation of Aldrin and Heptachlor in Soils As Influenced by Autoclaving, Moisture, and Soil Types12

Abstract

Aldrin was applied to Quartz sand, Plainfield sand, Carrington loam and muck soils in order to study its persistence and epoxidation. In addition autoclaved-wet and nonautoclaved dry sand and loam soils were used. Aldrin was readily transformed into dieldrin in a wet-nonautoclaved Carrington loam, but less rapidly so in a muck soil. The amounts of aldrin and dieldrin recovered from aldrin-treated Carrington loam soils were equal 3.3 months after treatment under laboratory conditions at 37• C. and 16 months after treatment under field conditions. In soils containing a low number of microorganisms (autoc1aved loam, Plainfield sand) or in dry soils the amount of dieldrin formed was small. After heptachlor had been applied to a Carrington loam it was found that this insecticide persisted slightly longer than aldrin, but the amount of heptachlorepoxide formed was smaller than that of dieldrin. A similar study on lindane persistence in a Miami silt loam is also reported.