Leaching Characteristics of the Endocrine Disruptor-suspected Pesticides in Upland Soil

This experiment was carried out to estimate leaching potential of thirteen endocrine disruptor-suspected pesticides in upland soils using soil columns (5 cm I.D. × 35 cm H.) packed with soil A (sandyloam) and soil B (loam). When 12.6 mL of water, average precipitation in Cheongju area during the periodfrom June to August, 2001-2010, was percolated through soil column packed with soil A every day for 21days, no pesticides were detected from leachate, with the exception of metribuzin which was detected withnegligible. Also, when 2 L of water was percolated consecutively five times through soil columns packedwith soil A and B, irrespective of soil types, cypermethrin, endosulfan, fenvalerate, parathion and trifluralin,which were very low water solubilities and high soil K oc s, were not detected from leachate and weredistributed mostly in the depth of 0-5 cm, representing that water solubility and soil K oc are majorcontributing factors to their leaching behavior. Despite high average leaching rates in carbaryl and methomyl,actual possibilities of ground water contamination in the agricultural environment by them would be verylow, considering that the negligible amount of pesticide was percolated through a lysimeter with anundisturbed soil core simulating the field conditions, while most of pesticide was percolated through a soilcolumn with the disturbed soil profile. Keywords Endocrine disruptor-suspected pesticide, leaching, soil column, leachate