Insecticide residues in pheasants after being fed on wheat seed treated with heptachlor and 14 C-lindane

Abstract

Different amounts of heptachlor-treated wheat seed containing 365 ppm heptachlor and 105 ppm trans -chlordane were fed to pheasants for different lengths of time, and residues in muscle, liver, brain and fatty tissues were determined at various times later. In general, residues of heptachlor epoxide (HE) in body tissues were related to the number of treated seed fed and the length of feeding time. Pheasants that were fed only 5 treated seed/day for 15 days had 0.17-0.23 ppm and 1.16-1.60 ppm HE in liver and fat, respectively, 14 days later. Feeding of 10 or 20 seed/day for 15 days resulted in higher levels of residues in all tissues. Consumption of only 5 or 20 treated seed by the pheasants in 1 day resulted in only 0.02 to 0.06 ppm HE in liver even after 14 days. Pheasants that were fed as many treated seed as they would eat (700-1240 seed or 9.9-17.5 mg of toxicant) in 1 day had very high levels (up to 32.5 ppm in fat) of residues 1 day later. Although residue levels of all tissues decreased with time, about 1.0 ppm and up to 0.07 ppm HE was present in fat and muscle, respectively, even after 90 days. Pheasants that were fed as many 14C-lindane-treated seed as they would eat (525-860 seed or 9-14.8 mg of toxicant) in 1 day had up to 1.12 and 2.48 ppm residue in muscle and liver, respectively, 1 day later. But these levels decreased very rapidly, and no residue could be seed dressings are less hazardous to seed-eating birds than heptachlor seed dressings and that the use of heptachlor should be discontinued.