Improved 3D-QSPR analysis of the predictive octanol–air partition coefficients of hydroxylated and methoxylated polybrominated diphenyl ethers

Abstract The octanol/air partition coefficient ( K OA ) is a key physicochemical parameter for describing the partition of organic pollutants between air and environment organic phase. The development of appropriate method to estimate K OA is of great importance. In the present study, the steric, electrostatic, hydrophobic, hydrogen bond donor and acceptor descriptors were computed by comparative molecular field analysis (CoMFA) and comparative molecular similarity indices analysis (CoMSIA). On the basis of these parameters, the statistically quantitative structure–property relationship (QSPR) models for log K OA of hydroxylated polybrominated diphenyl ethers (OH-PBDEs) and methoxylated polybrominated diphenyl ethers (MeO-PBDEs) congeners were developed using partial least-squares (PLS) analysis, of which the R 2 is about 0.980, 0.952 respectively. The electrostatic field was found to be main factors governing the log K OA . The results of validation indicate the models of this study exhibit optimum stability, and thus it is feasible to predict log K OA .