POTENCY OF 3,3′,4,4′,5-PENTACHLOROBIPHENYL (PCB 126), ALONE AND IN COMBINATION WITH 2,3,7,8-TETRACHLORODIBENZO-p- DIOXIN (TCDD), TO PRODUCE LAKE TROUT EARLY LIFE-STAGE MORTALITY

摘要

Newly fertilized lake trout (Salvelinus namaycush) eggs were exposed to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), 3,3′,4,4′,5-pentachlorobiphenyl (PCB 126), or their combination, and sac fry mortality was used to determine toxic potencies. The toxic equivalency factor (TEF) for PCB 126 was 0.0030. The dose-response curve for the PCB 126/TCDD mixture based on TCDD toxic equivalents was not significantly different from that for TCDD alone, suggesting additivity between the two congeners in causing sac fry mortality.