Toxicological Studies of Dow ET-57 in Cattle and Sheep1

Abstract

Dow ET-57 [O,O-dimethyl-O-(2,4,5-trichlorophenyl)phosphorothioate] administered orally to cattle was midly toxic at 125 mg/kg but not lethal at 400 mg/kg. Sheep were midly affected by 400 mg/kg. Symptoms of poisoning were first those of chlorinated phenol, then similar to other phosphate insecticides. Cholinesterase was depressed progressively over several days. Recovery from severe poisoning was slow, requiring up to 100 days.