organic pollution;  hydrophobic constant;  group contribution;  Model

The hydrophobic constant is a lipophilic parameter of organic pollutants and an important parameter of environmental science research and environmental protection evaluation. On the basis of the previous research work, a relatively simple and practical new model for predicting/calculating the hydrophobic constant of organic compounds was established. Using the stepwise regression optimization algorithm, the hydrophobic constant experimental data of 203 compounds were recognized as relatively accurate, and the contributions and parameter values of 49 groups were determined. According to the new hydrophobic constant contribution model, the hydrophobic constants of 203 compounds were calculated, which were compared with the experimental values, all within the general experimental error range, which proved that the proposed new group contribution model was feasible to predict/estimate the hydrophobic constants of organic compounds.