Record Display for the EPA National Library Catalog

RECORD NUMBER: 29 OF 54

OLS Field Name OLS Field Data
Main Title Physiologically Based Toxicokinetic Model for the Uptake and Disposition of Waterborne Organic Chemicals in Fish.
Author Nichols, J. W. ; McKim, J. M. ; Andersen, M. E. ; Gargas, M. L. ; Clewell, H. J. ;
CORP Author Environmental Research Lab.-Duluth, MN. ;Harry G. Armstrong Aerospace Medical Research Lab., Wright-Patterson AFB, OH.;Air Force Office of Scientific Research, Bolling AFB, DC.
Publisher c1990
Year Published 1990
Report Number EPA/600/J-92/006; AFOSR-ISSA-89-0060;
Stock Number PB92-136902
Additional Subjects Water pollution effects(Animals) ; Pharmacokinetics ; Trout ; Toxicity ; Perfusion ; Hemodynamics ; Body weight ; Biological models ; Reprints ; Pentachloroethane ; Tissue distribution ; Respiratory function tests ; Oncorhynchus mykiss
Holdings
Library Call Number Additional Info Location Last
Modified
Checkout
Status
NTIS  PB92-136902 Most EPA libraries have a fiche copy filed under the call number shown. Check with individual libraries about paper copy. NTIS 08/28/1992
Collation 17p
Abstract
A physiologically based toxicokinetic model was developed to predict the uptake and disposition of waterborne organic chemicals in fish. The model consists of a set of mass-balance differential equations which describe the time course of chemical concentration within each of five tissue compartments: liver, kidney, fat, and richly perfused and poorly perfused tissue. Model compartmentalization and blood perfusion relationships were designed to reflect the physiology of fishes. Chemical uptake and elimination at the gills were modeled as countercurrent exchange processes, limited by the chemical capacity of blood and water flows. The model was evaluated by exposing rainbow trout (Oncorhynchus mykiss) to pentachloroethane (PCE) in water in fish respirometer-metabolism chambers. Exposure to 1500, 150, or 15 microgram PCE/liter for 48 hr resulted in corresponding changes in the magnitude of blood concentrations without any change in uptake kinetics. The extraction efficiency for the chemical from water decreased throughout each exposure, declining from 65 to 20% in 48 hr. Extraction efficiency was close to 0% in fish exposed to PCE to near steady state (264 hr), suggesting that very little PCE was eliminated by metabolism or other extrabranchial routes. Parameterized for trout with physiological information from the literature and chemical partitioning estimates obtained in vitro, the model accurately predicted the accumulation of PCE in blood and tissues, and its extraction from inspired water. These results demonstrate the potential utility of the model for use in aquatic toxicology and environmental risk assessment. (Copyright (c) 1990 by Academic Press, Inc.)