Permethrin[3-phenoxybenzyl (1RS)-cis,trans-3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropane carboxylatel insecticides were selected to study adsorption and leaching potentials related to pollution on Commerce silty clay loam soil near Baton Rouge, Louisiana, USA. GLC-ECD chromatogram of permethrin included 32.5 % of cis-permethrin and 67.4 % of trans-permethrin. Extraction efficiencies of cis and trans-permethrin were 92.5 % and 92.3 in fortified water, respectively and 85.9 % and 88.8 % in fortified soil, respectively. At a 1:10 soil/water ratio,the Koc values for cis and trans isomers of permethrin were 938 and 877, respectively. Leaching of permethrin was evaluated in soil columns(5.4 cm i.d. × 26 cm length). Total recoveries of the permethrin applied to the soil column were 84.5 ± 3.1 %. When the soil columns were leached with three pore volumes of water, the distributions of cis-permethrin leached were 6.10 % and 0.07 % of amount applied in the untreated zone soil and leachate water, respectively. Trans-permethrin distributions were 5.20 % in the untreated zone soil and 0.05 % in leachate water. Cis and trans-permethrin was strongly adsorbed to soil. The results of the study showed the strong relationship between adsorption and leaching. Cis and trans-permethrin to be leached into the groundwater in soils with shallow aquifers were suggested a low leaching potential.

• Sam Edward Feagley
• Jung Ho Kim | 김정호