臺灣地區農田土壤有機氯農藥殘留境況及變遷

Distribution and fate of organochlorine pesticide residues in the field soil of Taiwan

部份有機氯農藥與降解產物被懷疑是內分泌干擾物質，會對環境生態造成衝擊，為監測這些物質在台灣地區農田土壤中之殘留，於2004年採集並檢測536件農田土壤樣品中有機氯農藥殘留量，結果顯示殘留農藥檢出率為76.1 %，殘留範圍由0.19-340μg/kg。有機氯農藥中檢出率最高者為DDE，檢出率達69.6%，檢出範圍由檢測不到至36.7μg/kg。除DDE與endosulfan之平均殘留量分別為2.42μg/kg與1.37μg/kg外，其餘有機氯農藥之平均殘留量皆低於1μg/kg。土壤有機氯農藥之殘留型態，主要以代謝物為主，且分佈於15-30cm深土層中。自1973年以來之監測資料估算田間消散半量期（DT_（50）），土壤中有機氯農藥田間消散半量期介於4.01-18.6年之間，其中以DDE的推估田間消散半量期最長，可達9.04-18.6年，最短則為表土中之DDT，其田間消散半量期為4.01年。

"Some of organochlorine pesticides and their metabolites are suspected as the disruptors of endocrine and impact on the environmental ecology. A total of 536 soil samples including surface soil (0-15 cm in depth) and bottom soil (15-30 cm in depth) collected from different fields in Taiwan were analyzed for understanding of the distribution and degradation of organochlorine pesticides in soil The results showed that 81.3 % of pesticide-positive samples were detected in soil, and the concentrations of residues were ranged from 0.19 to 340 μg/kg, DDE has the highest detection rate of 69.6 %, and the residue concentration ranged from ND to 36.7 μg/kg. The average residues of endosulfan and DDE in soil were 2.42 and 1.37 μg/kg, respectively. Except endosulfan and DDE, the average residue levels of other pesticides in soil were below 1 μg/kg. The metabolites of organochlorine pesticides were the main compounds in the bottom soil The dissipation rates of 50 % (DT_(50)) of pesticides in soil were calculated based on the data investigated in 1973, 1981 and 1994. The DT_(50) of aldrin, dieldrin, DDE, DDT, heptachlor and lindane were 10.6,4.90,18.6,5.74, 4.61 and 4.84 year, respectively."