生活饮用水中卤代烃检测能力的实验室间比对评估

Assessment on Inter-laboratory Comparison of Analytical Capacity on Halohydrocarbons in Household Drinking Water

[目的]通过实验室间比对有效评价和监控疾控系统实验室的检测技术水平,确定和核查实验室实施新方法检测的能力。[方法]该研究比对试验项目为生活饮用水中卤代烃7个组分的定量检测,参试实验室按照国家标准《生活饮用水标准检验方法有机物指标》(GB/T 5750.8—2006)、《利用实验室间比对的能力验证——第1部分:能力验证计划的建立和运作》(GB/T 15483.1—1999)和《利用实验室间比对的能力验证——第2部分:实验室认可机构对能力验证的选择和使用》(GB/T 15483.2—1999)规定的比对程序,分别检测A、B两个比对样品。通过统计分析,判定各参试实验室的检测能力。[结果]参加水中卤代烃检测项目的实验室共51个。其中,除1个实验室仅检测了三氯甲烷和四氯化碳项目外,其余50个均完成7个项目的比对。分析结果显示,比对试验结果的稳健变异系数(Robust CV)大部分<10.0%,结果的平均满意率为77.3%(|Z|≤2,结果满意),平均有问题率为9.4%(2<|Z|<3,结果有问题),平均不满意率为13.3%(|Z|≥3,结果不满意)。检测的水中卤代烃7个组分中,四氯化碳的结果满意率最高,为84.3%;一氯二溴甲烷结果满意率最低,为70.0%;二氯一溴甲烷不满意率最高,为22.0%;三氯乙烯不满意率最低,为6.0%。[结论]检测生活饮用水中7种卤代烃能力的实验室间比对结果表明,该次参试实验室的检测能力基本处于受控和可比状态。

[ Objective ] To determine and validate the capacity of performing analysis of the laboratories in the disease prevention and control channel by effectively evaluating and monitoring their proficiency of detection techniques via intercomparison of these labs. [ Methods ] The quantitative analysis of seven constituents of halohydrocarbons in household tap water was selected as the indices for this test. Two water samples for comparison, A and B, were analyzed by the participating labs separately. The results were statistically processed according to the intercomparison procedures specified in the National Standards： Standard detection method for household drinking water： Specifications of organics （ GB/T 5750.8--2006 ） as well as the Proficiency testing by interlaboratory comparisons Part 1： Development and operation of proficiency testing schemes （ GB/T 15483.1-- 1999 ） and Proficiency testing by interlaboratory comparisons Part 2： Selection and use of proficiency testing schemes by laboratory accreditation bodies（ GB/T 15483.2-1999 ）. [ Results ] Among the fifty one participating laboratories, fifty of them accomplished inter-laboratory comparison of results on seven analytes while one laboratory analyzed two analytes only, namely chloroform and carbon tetrachloride. The statistical results of this inter-laboratory comparison on analysis of halohydroearbons in water samples showed that most robust coefficients of variance were below 10% and the average rate of satisfaction of the results was 77.3% （ ｜Z｜≤ 2 results were satisfactory ）, while the average rate of unsatisfaction was 9.4% （ 2 〈 ｜Z｜〈 3 results were questionable ）. Among the seven constituents of halohydrocarbons analyzed, carbon tetrachloride had the highest rate （ 84.3% ）of satisfaction, and dibromoehloromethane had the lowest rate （ 70.0% ）of satisfaction; whereas monobromo-dichloro-methane had the highest rate （ 22.0% ） of unsatisfaetion, and trichloroethylene bad the lowest rate （ 6.0% ） of unsatisfaction. [ Conclusion ] The intercomparison results of the analysis of halohydrocarbons in household drinking water by the participating labs demonstrated that the analysis capacities of these labs are basically controllable and comparable.