The effect of some DDT and methoxychlor analogs on temperature selection and lethality in brook trout fingerlings

The effects of several DDT and methoxychlor analogs on trout fingerling temperature selection and lethality were investigated. The molecular requirements for lethality and alteration of temperature selection were different. Only p, p′-DDT, p, p′-DDD, and p, p′-methoxychlor were toxic in the range 10–50 ppb used. All the compounds tested, except DDE-type analogs, altered temperature selection. The effect of p, p′-methoxychlor on temperature selection progressively decreased until normal values were obtained 5 days after exposure. The effect of p, p′-DDT was still pronounced 9 days after exposure.