便携式固相微萃取-气质联用法结合离子隔离技术现场测定水中4种异味物质  

On-site Monitoring of Four Odor Substances in the Water Employing Portable Solid Phase Microextraction-Gas Chromatography Mass Spectrometry Combined with Select Ion Storage Technology

作　　者：梁宵 王许欣 周楠 宋兴伟[1] 卞静晶[1] 邵伟 夏文强 LIANG Xiao;WANG Xuxin;ZHOU Nan;SONG Xingwei;BIAN Jingjing;SHAO Wei;XIA Wenqiang(Jiangsu Provincial Environmental Monitoring Center,Nanjing,Jiangsu 210019,China;Hangzhou Puyu Technology Development Co.,Ltd.,Hangzhou,Zhejiang 311300,China)

机构地区：[1]江苏省环境监测中心,江苏南京210019 [2]杭州谱育科技发展有限公司,浙江杭州311300

出　　处：《环境监控与预警》2024年第6期42-47,共6页Environmental Monitoring and Forewarning

基　　金：江苏省环境监测科研基金项目(2208);江苏省省级生态环境科研项目(2023012)。

摘　　要：建立了便携式固相微萃取-气质联用法(SPME-GC-MS),结合离子隔离技术(SIS)现场测定水中4种异味物质(土臭素、2-甲基异莰醇、二甲基二硫醚、二甲基三硫醚)的方法,比较了全扫描(SCAN)、选择离子扫描(SIM)和SIS模式分析同一浓度4种异味物质的信噪比。结果表明,SIS模式的信噪比高,是SIM模式的1.6~3.6倍,方法灵敏度较好。在建立的实验条件下,4种异味物质检出限为0.6~1.5 ng/L,相关系数均>0.999,相对标准偏差为3.7%~8.1%,地表水实际样品的加标回收率为82.4%~97.8%。于2023年6—9月,在江苏省CC河现场监测地表水样品中的土臭素和2-甲基异莰醇,结果表明,不同点位间2种异味物质的质量浓度存在差异,各点位这2种物质的质量浓度随时间变化趋势一致,实际监测应用效果良好。分析土臭素、2-甲基异莰醇与水质指标水温、氨氮、总磷、总氮、浊度间皮尔逊(Pearson)相关系数,结果表明,2种物质与水质指标无显著相关性。该方法具有操作简单、快捷的优点,能够实现对水体中4种异味物质的现场快速监测。This paper established an on-site monitoring method for four odor substances(geosmin,2-methylisoborneol,dimethyl disulfide,dimethyl trisulfid)in water by using portable solid phase microextraction-gas chromatography mass spectrometry(SPME-GCMS)combined with select ion storage(SIS)technology.Compared with the full scan(SCAN)or selected ion monitor(SIM)technology,SIS showed great sensitivity with highest signal-to-noise ratios,surpassing those in the SIM mode by 1.6~3.6 times.Under the established experimental conditions,the detection limit of the four odor substances was between 0.6 and 1.5 ng/L,with linear coefficients greater than 0.999 and relative standard deviations ranging from^(3).7%to 8.1%.The recoveries from real surface water samples fell within the range of 82.4%to 97.8%.Monitoring on geosmin and 2-methylisoborneol in surface water sampled in CC River in Jiangsu Province between June and September in 2023 using this method unveiled concentration variations at different sampling locations.Consistent temporal trends in geosmin and 2-methylisoborneol concentrations were observed at each site,providing evidence of satisfactory monitoring efficacy.Pearson correlation coefficient analysis showed that there was no significant correlation between odor substance(geosmin,2-methylisoborneol)concentrations and water quality parameters(water temperature,ammonia nitrogen,total phosphorus,total nitrogen,and turbidity).This method is easy to operate and efficient,and is capable to achieve swift on-site monitoring of four odor compounds in water.

关 键 词：离子隔离技术 异味物质 便携式固相微萃取-气质联用法 现场监测 

分 类 号：X832[环境科学与工程—环境工程]