Environmental distribution of polychlorinated biphenyls by topology based characteristic root index

Abstract

Relationships between a newly developed index -which is based on topological characteristics ofthe molecules and called the Characteristic Root (CR) index- and the environmentally relevant physicochemical properties of the Polychlorinated Biphenyls, namely, aqueous solubility, vapour pressure, Henry's Law Corastants, and octanol-water partition coefficient are discussed. Correlations performed on the congeners clearly demonstrate that the CR index model accurately predicts the physicochelnicaiproperties of PCBs. Highcorrelationcoefficient (r = 0.998) was calculated for the linear one-parameter correlation between the CR index and molecular total surface area. So, the CR index was used in the prediction of pro2erties dependent on tetal surface area. The quality and reliability of the correlations are show to be high enough for environmental applications. Reported experimental physicochemical data of PCBs are tabulated, Recomended values are given for 58 of the 209 congeners, With the available data, it is possible to estimate what percentage of the chemical will be located in the soil, bottom sediments, water and air. The predicted and experimental physicochemical properties of PCBs were used to predict the environmental compartmentalization of these compounds in an evaluative environment using the fugacity approach.