Chemical, biological, and residue dissipation experiments with Thiodan

Abstract

The cyclodiene insecticides, including chlordane, heptachlor, aldrin, dieldrin, endrin, isodrin, and toxaphene, are highly chlorinated cyclic hydrocarbons with characteristic " endomethylene bridged" structures (Metcalf, 1955). All of these insecticides except toxaphene are produced by the Diels-Alder diene reaction (Metcalf, 1955). Little is known of the mode of action of these compounds except that all of them appear to affect adversely the nervous system of animals. Davidow and Radomski (1953) have shown that dogs convert heptachlor to heptachlor-epoxide and that this epoxide is stored in the fat. A similar conversion takes place in house flies (Perry^). It has recently been reported that aldrin is converted to dieldrin in the animal body (Bann _et al. , 1956); dieldrin is the epoxide of aldrin. The epoxides of hepta chlor (heptachlor-epoxide) and aldrin (dieldrin) are more toxic to animals than their respective precursors. The acute, oral LDgO values of the cyclodiene insecticides to the white rat range from about 10 to 600 mg. of toxicant per kg. of rat body weight (Metcalf, 1955). Chlordane, the first cyclodiene insecticide discovered, was reported and its insecticidal properties investigated by Kearns et al. (1945). ^Perry, A. S. 1958. Savannah, Ga. The metabolism of heptachlor by resistant and susceptible house flies. Private communication.