A pharmacokinetic analysis of the uptake of polychlorinated biphenyls (PCBs) by golden shiners

Abstract

A 96-h, static, nonconstant exposure design was used to assess pharmacokinetic parameters and to identify the rate-limiting process in polychlorinated biphenyl (PCB) uptake by golden shiners (Notemigonus crysoleucas). Fish were exposed individually to 14C-labeled PCBs corresponding to Aroclor 1254 (A1254). After various intervals (2–96 h), fish and water were analyzed for total radioactivity. Uptake of PCBs and decline of the external water concentration were both rapid. A clearance constant-based one-compartment model was used to represent the fish. Model-based equations for PCB concentrations in the fish and in the water were fitted simultaneously to the observed data with the PCNONLIN™ computer program. The absorption clearance constant was 30.8 ml·h−1·g−1 fish, which identified gill blood flow as the uptake rate-controlling process. The model-predicted apparent volume of distribution, Vd, and bioconcentration factor, Kb, were 5,280 ml/g fish and 9,059 ml water per gram fish, respectively. The model-predicted elimination rate constant, ke, was 5.84 × 10−3h−1, corresponding to a t1/2 of 4.9 d.