气相色谱—质谱法同时快速测定饮用水中38种半挥发性有机物

Simultaneous rapid determination of 38 semi-volatile organic compounds in drinking water by gas chromatography-mass spectrometry

半挥发性有机污染物(SVOCs)能在饮用水中长期稳定存在,具有致癌、致畸、致突变作用,以及内分泌干扰效应,因此,开发快速准确测定饮用水中SVOCs的分析方法至关重要。本文旨在建立一种基于气相色谱-质谱法同时测定饮用水中38种SVOCs的新方法,该方法采用液液萃取技术进行富集和萃取,并对样品预处理条件进行优化,确定50ml二氯甲烷为萃取剂、萃取时间10min、浓缩温度30℃为最佳预处理条件,萃取液浓缩至1mL,结合气相色谱质谱检测技术,采用选择离子监测模式,内标法定量。在优化条件下,38种SVOCs在10~1000μg·L^(-1)范围内线性良好,平均相对响应因子的相对标准偏差(RRF RSD)小于15%,方法检出限为0.001~0.09μg·L^(-1),定量限为0.004~0.36μg·L^(-1),在3个空白添加质量浓度(0.1、0.5和2.5μg·L^(-1))水平下进行回收试验,除联苯胺回收率低于70%外,其余目标物的回收率为70.1%~117%,相对标准偏差(n=6)为1.7%~9.2%。将建立的方法应用于12份饮用水样的检测,检出的物质以邻苯二甲酸二辛酯和邻苯二甲酸二丁酯为主,阿特拉津有部分检出,其余未检出。所建立的方法具有较高的选择性、灵敏度和准确度,为饮用水中SVOCs的高通量检测提供一种分析方法。

Semi-volatile organic pollutants can exist stably in drinking water for a long time and have carcinogenic,teratogenic and mutagenic effects as well as endocrine disrupting effects,therefore,it is crucial to develop analytical methods for the rapid and accurate determination of SVOCs in drinking water.The present paper is aimed at introducing a gas chromatography mass spectrometry based method for determining the 38 semi-volatile organic compounds in drinking water,the method described used liquid-liquid extraction technique for enrichment and extraction,to achieve the purpose,it is of course necessary to optimize the pretreatment conditions,and determined 50 ml of dichloromethane as the extractant,extraction time of 10 min and concentration temperature of 30℃as the best pretreatment conditions.Furthermore,the extracted extract can then be concentrated to 1 mL for the instrument analysis by means of a gas chromatography mass spectrometry and quantified by the internal standard method.Under the optimized conditions,38 SVOCs showed good linearity in the range of 10 to 1000μg·L^(-1),the relative standard deviation(RRF RSD)of the average relative response factor was less than 15%,the limits of detection of the method were 0.001 to 0.09μg·L^(-1),and the limits of quantification were 0.004 to 0.36μg·L^(-1).The recovery tests were performed at three blank spiked mass concentrations(0.1,0.5 and 2.5μg·L^(-1))levels,and the recoveries of the targets ranged from 70.1%to 117%with the relative standard deviations(n=6)of 1.7%to 9.2%,except for benzidine,which had recoveries lower than 70%.The established method was applied to the detection of 12 drinking water samples,and the detected substances were mainly dioctyl phthalate and dibutyl phthalate,with partial detection of atrazine and no detection of the rest.Therefore,the evaluation results we have gained can prove that the method we have developed enjoys the privilege of high selectivity,sensitivity and accuracy.And,so,it can be adopted as a novel method to determine the 38 semi-volatile organic compounds in drinking water.