農產品中農藥殘留量標準分析方法之建立－－甲基巴拉松、一品松、三氯松、亞特松、安殺番檢驗法

ANALYTICAL METHODS OF PESTICIDE RESIDUE IN CROPS PARATHION-METHYL EPN,TRICHLORFON, PIRIMIPHOS-METHYL AND ENDOSULFAN

本研究為配合衛生署77年4月公告農藥殘留容許量標準，參照國內外文獻資料，進行有機磷劑農藥甲基巴拉松、一品松、三氯松、亞特松及有有機劑氯劑安殺番於農產品中殘留量方法之建立與探討。建立以上五種農藥之檢驗方法，乃依據公告之容許標準量及標準量1/2倍、3/2倍添加於該作物，以進行三重覆之回收試驗，並求其最低偵測極限。結果發現；甲基巴拉松利用丙酮萃取，再以二氯甲烷進行抽取，經矽膠過濾層析管柱（Sep-Pak Silica Cartridge）淨化，以10%乙酸乙酯正己烷溶液沖提後，以氣相層析儀附火焰光度檢出器測之（FPD-P）；結果於米類分別添加0.25、0.5及0.75μ/g檢體濃度之平均回收率為89.3%～102.1%，最低偵測極限為0.5ppb 。一品松之萃取、淨化方法及偵測檢出器同上，結果於米類及雜糧類分別添加0.25、0.5及0.75；乾豆類添加0.05、0.1及0.15μ/g檢體濃度之平均回收率分別為米類93.0%～95.3%、雜糧類88.4%～101.8%及乾豆類90.1%～96.9%，最低偵測極限為3.0ppb。亞特松之萃取、淨化方法及偵測檢出器同上，結果於米類及小葉菜類分別添加0.75、1.5及2.25μ/g；包葉菜類添加0.25、0.5及0.75μg/g檢體濃度之平均回收率分別為米類89.4%～95.1%、小葉菜類94.1%～102.5%及包葉菜類98.2%～102.2%，最低偵測極限為1.0ppb。安殺番之萃取、淨化方法同上，但以氣相層析儀附電子捕獲檢出器測之（ECD-63Ni）, 結果於小葉菜類及包葉菜類分別添加1.0、2.0 、3.0；乾豆類添加0.25、0.5及0.75μ/g檢體濃度之平均回收率分別為小葉菜類81.2%～85.5%、包葉菜類85.3%～94.1%及乾豆類94.1%～102.0%，最低偵測極限為O.1ppb。三氯松利用丙酮萃取，於緩衝溶液中以二氣甲烷進行抽取，經活性炭過濾層析管柱（SPICE Charcoal Cartridge）淨化，以苯／乙酸乙酯（1/4）溶液沖提後，以氣相層析儀測之（FPD-P），結果於柑桔類分別添加0.1、0.2及0.3μg/g檢體濃度之平均回收率為85.6%～91.7%，最低偵測極限為1.0ppb。本實驗經實際添加於各類作物所得回收率、再現性及最低偵測極限之結果良好得知，以上之三種檢驗方法均各別適用於甲基巴拉松、一品松、三氯松、亞特松及安殺番其已公告容許量標準之各類作物。

The Department of Health enforces pesticide residue tolerances for a variety of raw agricultural products, to fulfil these regulation, the analytical methods for measuring pesticide residue in crops were studied. The present report was the methods to identify and quantify of Parathion- methyl, EPN, Trichlorfon, Pirimiphos-methyl and Endosulfan. A Gas-liquid chromatographic methods for determination of Parathion-methyl, EPN, Trichlorfon, Pirimiphos-methyl, and Endosulfan residues was developed. The test portion of crops was firstly homogenized with acetone and partitioned by dichloromethane (pH was adjected to 4.5 only for Trichlorfon). The pesticide residue was then cleaned up with silica cartridge for 4 pesticides except Trichlorfon (purified with activated-carbon). Then Parathion-methyl, EPN, Trichlorfon and Primiphos-methyl were analyzed by GC-FPD while Endosulfan by GC-ECD. All samples were fortified with varies concentrations of standard solution. The average recoveries of pesticides ranged from 81.2% to 102.1%. The detection limit of these methods were as follows : Parathion-methyl 0.5 ppb, EPN 3.0 ppb, Pirimiphos-methyl 1.0ppb, Endosulfan 0.1ppb, and Trichlorfon 1.0ppb.