环境水体中致嗅有机物分析的样品前处理技术研究进展

Progress in Pre-treatment Techniques for Analysis on Odorous Compounds in Environmental Water

环境水体中致嗅有机物种类繁多,常见的土霉味物质包括土臭素(GSM)、2-二甲基异茨醇(MIB)、2-甲氧基-3-异丙基吡嗪(IPMP)、2-甲氧基-3-异丁基吡嗪(IBMP)和2,4,6-三氯代苯甲醚(TCA)等,其在水中的质量浓度一般在ng/L～μg/L水平且嗅阈值较低。该文总结了测定环境水体中痕量土霉味物质的气相色谱-质谱法,并对闭环捕集、吹扫捕集、液液萃取、固相萃取、固相微萃取、液相微萃取和搅拌棒吸附萃取7种样品前处理技术进行了介绍和对比。重点介绍了目前应用最广泛的顶空固相微萃取技术和新发展的液相微萃取、搅拌棒吸附萃取技术在环境水体中致嗅有机物分析中的应用,并展望了致嗅有机物的分析方法。

There are various types of odorous compounds in environmental water. The common earthy - musty odorants include trans-1, lO-dimethyl-trans-9-decalol（ GSM）, 2-methylisoborneol （ MIB）, 2- methoxy-3-isopropylpyrazine （ IPMP）, 2-methoxy-3-isobutylpyrazine （IBMP） and 2, 4, 6-trichloro- anisole（TCA）. These five compounds with lower odor threshold concentration usually exist in water at the level of ng/L - μg/L. The trace amount of these substances can also create undesirable taste and odors because of their volatility or semi-volatility. It is necessary to concentrate these compounds in samples and establish a highly sensitive determination method. In this paper, the determination methods for trace odorous compounds by gas chromatography - mass spectrometry（ GC - MS） are re- viewed. The pre-treatment techniques including closed-loop stripping analysis （CLSA） , purge and trap （ PT）, liquid - liquid extraction （ LLE ）, solid phase extraction （ SPE ）, solid phase microextrac- tion（SPME）, liquid phase microextraction（LPME） and stir bar sorptive extraction（SBSE） are sum- marized and compared. Among them, the application of three methods, including headspace solid phase microextraction（HS-SPME） which is by far the most frequently applied technique, LPME and SBSE which are newly developed techniques on the sample enrichment of earthy - musty compounds in environmental water are mainly introduced. In addition, the outlook for development of the analysis methods for odorous compounds is discussed.