Comparison of two methods for estimation of soil sorption for imidacloprid and carbofuran.

Predicting the fate and transport of pesticides in soil environment is an important issue especially in understanding and modelling of the environmental behaviour of pesticides. Classical batch sorption method often has been identified as insufficient to derive the actual extent of sorption. In this study, the batch equilibrium method was compared to the centrifugation method, which can permit measurement of sorption under more natural conditions. The results of the comparison of the batch with the centrifugation method for imidacloprid and carbofuran pesticides indicate that the batch method overestimates sorption in comparison to the centrifugation method. These results are in agreement with others, which use high soil:solution ratios with batch and those that used the centrifugation method.