Metabolism and disposition of 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin in ring-necked pheasant hens, chicks, and eggs

The 11/2 for whole-body elimination of [³H]-2, 3, 7, 8-tetrachlorodibenzo-p-dioxin (TCDD)derived radioactivity in ring-necked pheasant hatchlings was 13 d, whereas in adult hen pheasants that were not producing eggs it was 378 d. All TCDD-derived radioactivity in hentissues was from the parent compound. The oral bioavailability of TCDD in the adult hen pheasant varied with the environmental matrix, with 30% of the dose absorbed from a suspension of earthworms, 33% absorbed from a soil suspension, 41% absorbed from a suspension of paper mill sludge, and 58% absorbed from a suspension of crickets. A cumulative dose of1.0 fig TCDD/kg body weight, administered as weekly doses of 0 1 µg/kg for 10 wk, did not adversely affect hen condition or.