Interactions of 2,3,7,8-tetrachlorodibenxo-p-dioxin (TCDD) and 3,3′4,4′,5-pentachlorobiphenyl (PCB 126) for producing lethal and sublethal effects in the Japanese medaka embryos and larvae.

Newly fertilized eggs and one-month-old larvae of Japanese medaka (Oryzias latipes) were exposed to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), 3,3',4,4',5-pentachlorobiphenyl (PCB 126), or their mixtures to evaluate their interaction using several toxic end points. The uptake of TCDD and PCB 126 in a binary mixture increased with dose and was not significantly different from that of each congener alone. The elimination of TCDD and PCB 126 in the binary mixture in the Japanese medaka larvae was also not significantly different from that of the individual congener. PCB 126 (94 - 300 pg/ml) and TCDD (1.8 - 6.2 pg/ml) acted additively to produce mortality and the other toxic effects measured in the Japanese medaka embryos and larvae at the average ratios of 47:1 and 55:1, respectively. (C) 1997 Elsevier Science Ltd.