摘要
目的:优化生活饮用水中三卤甲烷和四氯化碳的顶空气相色谱测定方法。方法:从样品保存、前处理、基质空白、顶空进样、标准系列溶液配制等方面,对《生活饮用水标准检验方法第8部分:有机物指标》(GB/T 5750.8—2023)中顶空毛细管柱气相色谱法进行改进。采用全自动顶空技术,在顶空瓶内加入3.7 g NaCl,涡旋混匀后避光冷藏(可保存72 h),平衡温度70℃,平衡时间30 min,标准系列溶液采用开口瓶技术配制。结果:三氯甲烷、二氯一溴甲烷、一氯二溴甲烷、三溴甲烷、四氯化碳的检出限分别为0.0055、0.0038、0.0061、0.014μg·L^(-1)和0.0012μg·L^(-1),在0.4~80.0μg·L^(-1)采取二次曲线拟合,相关系数均大于0.999,相对标准偏差分别为2.89%~6.69%、3.47%~5.48%、3.90%~5.85%、3.42%~7.66%、1.72%~6.13%,加标回收率分别为80.0%~106.0%、87.5%~104.8%、90.0%~105.1%、82.5%~105.8%、82.5%~106.1%。结论:优化后的方法提高了检测的精密度、准确度,拓宽了线性范围,简化了操作流程,可有效提升日常监测效率。
Objective:To optimize the headspace gas chromatography method for the determination of trihalomethanes and carbon tetrachloride in drinking water.Method:Improvements were made to the headspace gas chromatography method described in Standard Examination Methods for Drinking Water—Part 8:Organic Indices(GB/T 5750.8—2023)in terms of sample preservation,pretreatment,matrix blanks,headspace injection,and standard solution preparation.Using fully automated headspace technology,3.7 g of NaCl was added to the headspace vial,mixed by vortexing,and stored in the dark at low temperature(can be stored for 72 h).The equilibrium temperature was set at 70℃for 30 min,and standard solutions were prepared using the open-vial technique.Result:The limits of detection for chloroform,bromodichloromethane,dibromochloromethane,bromoform,and carbon tetrachloride were 0.0055,0.0038,0.0061,0.0140μg·L^(-1),and 0.0012μg·L^(-1),respectively.In the concentration range of 0.4~80.0μg·L^(-1),second-order curve fitting was applied,with correlation coefficients greater than 0.999.Relative standard deviations ranged from 2.89%~6.69%,3.47%~5.48%,3.90%~5.85%,3.42%~7.66%,and 1.72%~6.13%,and spike recoveries ranged from 80.0%~106.0%,87.5%~104.8%,90.0%~105.1%,82.5%~105.8%,and 82.5%~106.1%,respectively.Conclusion:The optimized method improves precision and accuracy,broadens the linear range,simplifies the operational procedure,and can effectively enhance routine monitoring efficiency.
作者
褚添
史瑞崎
CHU Tian;SHI Ruiqi(Beijing Mentougou District Center for Disease Prevention and Control,Beijing 102300,China)
出处
《食品安全导刊》
2025年第27期63-69,79,共8页
Food Safety Guide Magazine
关键词
顶空气相色谱法
三卤甲烷
四氯化碳
生活饮用水
headspace gas chromatography
trihalomethanes
carbon tetrachloride
drinking water
