陕西省生活饮用水中挥发性有机物含量的监测

Monitoring of volatile organic compounds in drinking water in Shaanxi

目的建立吹扫捕集/气相色谱-质谱仪测定水中27种挥发性有机物的方法,了解陕西省部分地区生活饮用水中挥发性有机物(VOCs)的污染情况。方法采用吹扫捕集法富集水中的挥发性有机物,解析后用气相色谱-质谱联用仪测定,选择特征离子定量。对陕西省121份生活饮用水中27种挥发性有机物进行监测。结果在0.50μg/L^20.0μg/L质量浓度内呈良好的线性关系,相关系数在0.996 4~0.999 3,回收率在77.4%~99.4%,满足分析要求。121份生活饮用水中有98份检出了三氯甲烷、1,2-二氯乙烷、苯、三溴甲烷、甲苯、一溴二氯甲烷、二溴一氯甲烷、二氯甲烷、1,1,1-三氯乙烷共9种挥发性有机物,其余18种未检出,其中三卤甲烷作为最主要的消毒副产物,检出率为30.6%~81.0%。结论本省部分生活饮用水受到VOCs不同程度的污染,虽未超标,但对人体健康仍构成潜在危害。

Objective To establish a method for the quantitative detection of 27 kinds of volatile organic compounds（ VOCs）and investigate the pollution situation of VOCs in drinking water in Shaanxi province. Methods VOCs in water were purged and trapped,then desorbed and analyzed by purge and trap-gas chromatography/mass spectrometry（ GC/MS）. Characteristic ions were used for quantitative measurement. 27 kinds of VOCs in 121 drinking water samples were determined and monitored.Results Good linearity was obtained when the concentrations of 27 kinds of VOCs were within 0. 50 μg/L-20. 0 μg/L,the correlation coefficient（ r） was within 0. 996 4-0. 999 3,the recovery of the method was within 77. 4%-99. 4%,which can meet the requirement of analysis. 9 kinds of VOCs in the 98 water samples were detected,including chloroform,1,2-dichloroethane,benzene,bromoform,toluene,bromodicloromethane,dibronochloromethane,methylene chloride,1,1,1-richloroethane,but the other 18 kinds of VOCs were not detected. Trihalomethane was the main disinfection by-product,and the detection rate was within 30. 6%-81. 0%. Conclusion Some kinds of VOCs were detected in the drinking water,and their concentrations were low and not excessive,but they still can cause potential hazards to human health.