Residues in cutthroat trout (Salmo clarki)and California newts (Tarichia torosa)from a lake treated with technical chlordane.

Abstract

A lake was sprayed with technical chlordane to give a concentration of approximately 10 ppb. Resident California newts (T. torosa) and cutthroat trout (S. clarki) were subsequently collected and analyzed for residue concentrations. The newts were collected at 14, 279, 451 and 1036 days and the trout at 93, 279, 421 and 1014 days. At first, the concentrations of residues were very high in both species, and their composition, except for heptachlor, resembled that of technical chlordane. The heptachlor was quantitatively epoxidized in newts after 14 days; in trout, some heptachlor was still present after 93 days. Concentrations of total chlordane in body tissues of both species declined more than 98% with time. Of 7 individually determined constituents of technical chlordane, trans-nonachlor was by far the most persistent, accounting for 49-55% of total chlordane in specimens collected last. Both animals produced oxychlordane, probably from .gamma.-chlordane. Heptachlor, heptachlor epoxide and .gamma.-chlordene were nondetectable in both species after 279 days. The California newt evidently metabolizes and eliminates chlordane residues more effectively than the cutthroat trout.