Bioaccumulation Kinetics and Bio Concentration Factors of Few Polychlorinated Biphenyls: A Study on Freshwater Fish Puntius ticto

Abstract

The present work aims to understand the bioaccumulation kinetics and bioconcentration factors (BCF) of the Polychlorinated Biphenyls (PCBs) PCB 126 and PCB 169 in tissues of fish Puntius ticto. A continuous fed system was used to carry out the study. Bioconcentration in the tissues of the fish has been summarised using a first order uptake model. Fish were exposed to the PCBs continuously for a period of 30 days and this exposure has been used to calculate the steady state of BCF. The gill tissue of P. ticto showed a maximum rate of bioaccumulation of 30.61 μg g-1 wet weight for PCB 169 and 19.91 μg g-1 wet weight for PCB 126 respectively. In this study, the regression coefficients (R2), were found to vary between 0.736 and 0.97. This is indicative of a good to high correlation between the PCB concentration and exposure time. Prediction of the Octanol water partition coefficient (Kow) has been carried out to demonstrate the hydrophobic property of PCB compounds and their attraction towards lipid. The actual calculated BCF values have been used to predict the Kow values. Results indicate that it is possible to correlate the Kow values with both the lipid content of the tissue and the exposure time, in case of either PCB, and that the burden of PCB differs from one tissue to another.