ALLOMETRY IN THE UPTAKE OF HYDROPHOBIC CHEMICALS DETERMINED IN-VIVO AND IN ISOLATED-PERFUSED GILLS

Uptake rate constants of different classes of hydrophobic organic chem icals have been determined in isolated perfused gills of rainbow trout (Oncorhynchus mykiss) as an alternative for studies in vivo, The upta ke rate constants have been compared to those determined in guppy, Poe cilia reticulata, in vivo. The organic chemicals which have been used are anthracene, hexabromobenzene, octachloronaphthalene, octachlorodib enzo-p-dioxin, phenol, polychlorinated anisoles, polychlorinated benze nes, polychlorinated biphenyls, and tetrachloroveratrole. Uptake rate constants in guppy are higher than those in rainbow trout gills, and s how relatively high variation in both gills and guppy, When uptake rat e constants in each study are normalized for that of pentachlorobenzen e (pCBz), variation is significantly reduced both in perfused gills an d in guppy, An allometric relationship is derived between weight and u ptake rate constant. Uptake rate constants determined in one fish can thus be used for prediction of those in other fishes, When a reference chemical, such as pCBz, is included, the gill perfusion experiments c an be highly suitable to determine uptake rate constants of organic ch emicals, which can be extrapolated to fish of different sizes. (C) 199 5 Academic Press, Inc.