固相萃取–气相色谱法测定饮用水中5种有机磷农药

建立了固相萃取–气相色谱法测定饮用水中敌敌畏、乐果、甲基对硫磷、马拉硫磷及对硫磷的方法。采用Cleanert PEP–SPE固相萃取柱,以二氯甲烷、乙酸乙酯、甲醇及纯水活化固相萃取柱,以5 m L/min流量富集水样,然后用二氯甲烷及乙酸乙酯洗脱浓缩后进行气相色谱分析。5种有机磷农药线性相关系数均大于0.995,方法测定下限为0.16~0.80μg/L,加标回收率为59.8%~109.0%,测定结果的相对标准偏差小于16%(n=6)。该方法灵敏度高,准确度好,适用于饮用水中5种有机磷农药的检测。

Determination of Five Kinds of Organic Phosphorus Pesticides in Drinking Water by Automatic Solid-Phase Extraction-Gas Chromatography

A method for determination of 5 kinds of organic phosphorus residues, including dichlorvos, ddimethoate, methyl parathion, malathion, parathion in drinking water by solid-phase extraction–gas chromatographic was developed. Cleanert PEP–SPE concentrated cartridge was selected, dichloromethane, ethyl acetate, methanol and water as the solvents of extraction, 5 mL/min concentrated rate of drinking water, cleaning-up solvents of dichloromethane and ethyl acetate were used to enrich organic phosphorus in water sample, and then the sample was detected by gas chromatography. The correlation coefficients of 5 kinds of organic phosphorus were all more than 0.995 and the determination limits were 0.16–0.80μg/L. The average recoveries of 5 kinds of organic phosphorus ranged from 59.8% to 109.0% with relative standard deviations less than 16%(n=6). This method has high sensitivity and good accuracy. It can meet the determination requirements of the fivekinds of organic phosphorus residues in drinking water.