Record Display for the EPA National Library Catalog


Main Title Disposition and Excretion of Intravenous 2,3,7,8-Tetrabromodibenzo-p-dioxin (TBDD) in Rats.
Author Kedderis, L. B. ; Diliberto, J. J. ; Birnbaum, L. S. ;
CORP Author Health Effects Research Lab., Research Triangle Park, NC. Environmental Toxicology Div. ;National Inst. of Environmental Health Sciences, Research Triangle Park, NC. ;North Carolina Univ. at Chapel Hill.
Publisher c1991
Year Published 1991
Report Number EPA/600/J-91/123;
Stock Number PB91-211466
Additional Subjects Pharmacokinetics ; Toxicology ; Feces ; Tissue distribution ; Adipose tissue ; Liver ; Skin(Anatomy) ; Dose-response relationships ; Body weight ; Rats ; Weight gain ; Muscles ; Blood ; Bile ; Reprints ; Tetrabromodibenzodioxins
Library Call Number Additional Info Location Last
NTIS  PB91-211466 Some EPA libraries have a fiche copy filed under the call number shown. 07/26/2022
Collation 12p
Polybrominated dibenzodioxins and dibenzofurans are of toxicologic interest due to potential occupational and environmental exposure and because of their structural similarity to the highly toxic chlorinated analogues. The excretion and terminal tissue distribution of (3)H-TBDD was studied in male F344 rats for 56 days following single doses of 0, 0.001 or 0.1 micro mol/kg. The major tissue depots of radioactivity in liver, adipose, and skin, and tissue distribution was dose-dependent. At 56 days, liver concentrations in the high dose group were disproportionately increased compared to the low dose group. Liver:adipose concentration ratios were 0.2 and 2.6 at the low and high doses, respectively. Elimination of radioactivity in the feces, the major route of excretion, and urine was also nonlinear with respect to dose. By day 56, feces accounted for approximately 50% of the administered dose at the low dose versus 70% at the high dose. Blood levels of radioactivity declined rapidly with approximately 2% remaining in the blood by 24 hours. Radioactivity levels in the liver peaked by 7 hrs and then gradually declined concomitant with a slow accumulation in adipose tissue. The terminal excretion half-life of radioactivity in adipose was estimated to be approximately 60 days. Liver:adipose concentration ratios declined with time. Thus, the overall disposition of TBDD appears similar to that observed for the chlorinated analogue, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). The dose-dependent tissue disposition and excretion kinetics of these compounds suggest important considerations for extrapolations from high to low doses.