Effect of Two Nonionic Surfactants on Adsorption and Mobility of Selected Pesticides in a Soil‐System

Abstract

The effect of two nonionic surfactants on the adsorption and mobility of lindane, diuron, and atrazine in soil columns was studied. A wide range of surfactant concentrations was used in this study. Adsorption of the pesticides by soil from a surfactant solution was inversely related to the leaching of the pesticides through the soil in presence of the surfactants. Low concentrations of both surfactants did not influence adsorption and mobility of the pesticides. A marked increase in the adsorption and reduction in the mobility of the pesticides was observed with 500 ppm Aqua Gro and 2,000 ppm Soil Penetrant. At concentrations of 5,000 ppm and 10,000 ppm, both surfactants decreased the adsorption and increased the mobility of lindane and diuron, but did not influence the adsorption and mobility of atrazine. An attempt was made to explain the mechanisms by which the two surfactants influence adsorption and mobility of the pesticides using the concept of micelle formation and critical micelle concentration.