Quantitative structure-sorption relationships of pesticides used in the sugarcane industry in the northern coastal area of Paraíba State, Brazil

Abstract

Sorption coefficients (Koc) are useful in the prediction of whether a pesticide will remain dissolved in solution or will become adsorbed onto soil particles after its application. Measuring this process experimentally is difficult, expensive and time-consuming. Hence, much effort has been directed toward estimating Koc through statistical modelling. In this study, we investigated the physicochemical properties of pesticides employed by a local sugarcane company, in the northern coastal plain of Paraíba state in Brazil, by using several molecular descriptors, among them, GRid INdependent Descriptors (GRIND). Quantitative assessment of the structure-property relationship (QSPR) model indicated that size, shape, octanol-water coefficient, solubility and the balance between hydrophilic and lipophilic regions, are all relevant to Koc values.