Bioconcentration of bromo- and chlorobenzenes by fish (Gambusia affinis)

Bioconcentration factors, uptake rate constants (k(1)), and clearance rate constants (k(2)) were determined for bromo- and chlorobenzenes with the mosquito fish (Gambusia affinis). The values of k(1) and k(2) on a lipid weight basis ranged from 3500 to 47,000 d(-1) and 1.50 to 0.27 d(-1), respectively. The rate constants exhibit good nonlinear correlations with the n-octanol/water partition coefficient (K-ow). The bioconcentration factors reach a maximum at pentachlorobenzene (log K-ow = 5.2) and then decline. The bioconcentration factors on a lipid weight basis (K-BL) correlated well with K-ow. The bioconcentration kinetics can be described by equivalent mass transfer models and experimental data indicate that the mass transfer process in the lipid phase is the rate-limiting step in the bioconcentration process. Copyright (C) 1996 Elsevier Science Ltd