Distribution and elimination of a polychlorinated biphenyl after acute dietary exposure in yellow perch and rainbow trout.

Distribution and elimination of a single polychlorinated biphenyl isomer (2,5,2',5'-tetrachloro[14C]biphenyl, 4-CB) were compared in a nonfatty fish (yellow perch) and a fatty fish (rainbow trout). Adult fish were exposed acutely to 4-CB (0.8 microgram/fish) by the oral or intraperitoneal route and were killed at designated times thereafter for one month. Whole body elimination of 4-CB was similar in both species with 20 to 30% of the radioactive 4-CB being eliminated in the first 3 to 4 days after treatment, but very little thereafter. Also, the same extent of elimination was seen when the compound was given orally or intraperitoneally. Tissue distribution of 4-CB residues was different in the two species. Perch relied on viscera and carcass as main 4-CB distribution sites and skeletal muscle, skin and scales as minor sites. In rainbow trout, on the other hand, skeletal muscle and carcass were major distribution sites, whereas viscera and skin were minor sites. This species difference in 4-CB distribution was not due to a difference in sexual maturity of the perch and trout, because a build-up of eggs or sperm was not present in the peritoneal cavity of either species.