Quantitative structure-activity relationship for the depuration rate constants of polychlorinated biphenyls in the...

Partial least squares (PLS) regression together with 16 theoretical molecular structural descriptors was successfully used to develop a quantitative structure-activity relationship (QSAR) model on the depuration rate constants (k(d)) of polychlorinated biphenyls (PCBs) in freshwater mussel Elliptio complanata. The cross validated Q(2)(cum) and the correlation coefficient R for the model is 0.871 and 0.941, respectively. The achievement of satisfactory Q(2)(cum) and R values indicate significant high robustness and good predictive ability of the model. The model was tested as acceptable for prediction of logk(d) (the log of the depuration rate constants) by validation set. The significant descriptors governing logk(d) include polarizability (alpha), core core repulsion energy (CCR), molecular weight (M(w)), total energy (TE), and electronic energy (EE). The key descriptors in the model reflect that van der Waals interactions play a dominant role in the depuration of PCBs. The depuration of PCBs in Elliptio complanata may be mainly attributed to the biota-water phase partitioning processes.