【作者】 张振伟；

【导师】 鄂学礼； 张岚；

【作者基本信息】 中国疾病预防控制中心 ， 劳动卫生与环境卫生学， 2010， 硕士

【摘要】 由于我国水环境污染,水源恶化,导致我国饮水嗅味事件时有发生。自2007年5月太湖蓝藻水华致无锡自来水发臭事件发生以来,秦皇岛洋河水库、安徽巢湖、云南滇池、武汉东湖等地区相继暴发了类似饮水异嗅异味的事件,直接影响了当地居民的日常生活,受到社会各界的普遍关注和重视。水中致嗅物质种类繁多,且含量极低(ppt级),不易进行富集检测。虽然饮水检验方法中已建立了“臭和味”的标准检验方法,但其为感官定性测试,目前国内尚未建立水中致嗅物质的定性定量标准检验方法。本课题通过实验研究,建立了藻污染水中致嗅物质土臭素(GSM)、2-甲基异莰醇(MIB)和二甲基三硫醚(DMTS)的测定方法,为制定饮用水中致嗅物质标准检验方法提供科学依据。主要研究内容与结果包括：1、选择GSM、MIB和DMTS作为目标化合物。GSM和MIB是藻污染水源中最为常见的两种致嗅物物质,无论河流还是湖库型水源,MIB在水源中常被检出,而GSM在部分湖库水源中也有检出,同时这两种物质也是季节性土霉味问题的主要来源。DMTS是已确认水腥臭味的典型致嗅物质,研究表明,此物质为2007年无锡蓝藻嗅味事件的主要致嗅物质。因此,本课题选择了GSM、MIB和DMTS作为研究的目标化合物。2、选择固相微萃取法(SPME)作为实验的前处理方法。对四种前处理方法[固相萃取法(SPE)、液液萃取法(LLE)、吹扫捕集法(P&T)、固相微萃取法(SPME)]的进行了选择,结果表明,针对选定的目标化合物,SPE和LLE的回收率较低,P&T的灵敏度较低,不适宜作为本实验的前处理方法。SPME的灵敏度高,准确度和精密度较好,适合富集饮用水中的致嗅化合物,因此,选择SPME作为本实验的前处理方法。3、通过对SPME前处理条件及气相色谱和质谱测定参数进行研究,提出了饮用水中GSM.MIB和DMTS固相微萃取的最佳实验条件,并确定了气相色谱／质谱检测的最佳参数设置,建立了饮水中GSM、MIB和DMTS的固相微萃取-气相色谱／质谱(SPME-GC/MS)测定方法。4、对SPME-GC/MS测定饮用水中GSM.MIB和DMTS的方法学研究。实验结果表明,三种待测物的最低检出限为0.7ng/L～1.6ng/L,定量检出限为2.2ng/L～5.3ng/L,RSD为2.3%-8.7%,自来水中的加标回收率为80.1%-96.9%,河水中的加标回收率为92.5%-102.5%。该方法的灵敏度高,准确度好,精密度也较好,能满足地表水及生活饮用水中的GSM.MIB和DMTS的分析。5、应用所建SPME-GC/MS方法测定了实验室培养的含鱼腥藻水样及现场采集的实际水样。结果发现：含鱼腥藻水样中,GSM的浓度为751ng/L,MIB的浓度为20.2ng/L,未检出DMTS;太湖北闸口蓝藻打捞点所采水样中,检出MIB的浓度为10.1ng/L；滇池原水中,检出GSM的浓度为6.32ng/L,DMTS浓度为195ng/L,未检出MIB。6、本课题建立的饮用水中GSM、MIB和DMTS的SPME-GC/MS测定方法,具有操作简便、分析较快、定量准确的特点,经实际水样的检测验证,方法特性符合实际样品的分析要求。7、本课题提出的饮用水中GSM.MIB和DMTS的SPME-GC/MS测定方法是可行的,基本达到了课题设计的研究目标。更多还原

【Abstract】 With the deterioration of source water quality,drinking water odor events in our country occur more frequently. Since May in 2007 the outbreak of ordor problem cau-sed by algal blooms in Taihu Lake,Yanghe reservoir in Qinhuangdao,Chaohu Lake in Anhui province and Dianchi Lake in Yunnan province have outbreaks of similar odor events one after another.These odor incidents has affected the daily life of local resid-ents and also attracted a lot of public attention.The compounds causing odor in water may be at trace levels and complicated, so their qualitative and quantitative tests are relatively difficult.Rencently there is not standard methods of determinating odor compounds in drinking water in our country.Through researching in this study, to establish the method for determining geosmin, dimethyl trisulfide and 2-methylisoborneol in drinking water and to provide scientific basis for formulating the standard methods of determinating odor compounds in drinking water.The main results are summarized as follows:1 To choose geosmin, dimethyl trisulfide and 2-methylisoborneol as the target compounds. Geosmin and 2-methylisoborneol are the most frequent ordor compounds in our source water which can be detected in most lake sources and river soueces.Dimethyl trisulfide has been confirmed to be the typical compound to produce marsh smelland it has been included in the Taste/odor wheel.lt is reported that dimethyl trisufide is one of the main odor compounds causing odor problem in Wuxi 2007.2 To choose the method of solid phase microextraction (SPME)as the pretreatment of samples.Through the comparison and discussion of four pretreating methods including solid-phase extraction, liquid-liquid extraction, purge and trap and solid phase microextraction,the result shows that the recoveries of SPE and LLE is lower and the sensitivity of P&T is lower.Nevertheless the recoveries and sensitivity of SPME which is more suitable to enrich the odor compounds in drinking water are better.3 Through researching on the conditions for SPME and the parameters for GC/MS,to propose the optimal conditions for SPME and the optimal parameters for GC/MS,and establishing the method for determining geosmin,2-methylisoborneol and dimethyl trisulfide in drinking water with SPME-GC/MS.4 The methodology indexs of SPME-GC/MS which determine geosmin,2-met-hylisoborneol and dimethyl trisulfide in drinking water was studied and evaluated.It was found that detection limits for three compounds were between 0.7ng/L～1.6ng/L and limits of quantaion were between2.2 ng/L～5.3ng/L.RSD was between 2.3%～8.7%.Recoveries for tap water analyses ranged between 80.1%～96.9% and recoveries for river water analyses ranged between 92.5%～102.5%.The methodology indexs of this method were better, so it can be used to determine the odor compounds in drinking water.5 Determined the water samples including anabaena algae and some field water samples.In the anabaena algae water,the determination of geosmin reached 750.71ng/L, determination of 2-methylisoborneol was only 20.21ng/L and dimethyl trisulfide was not detected.In the water sample of Taihu Lake, determination of 2-methylisoborneol was 10.10ng/L.In the water sample of Dianchi,the determination of geosmin was 6.32ng/L, determination of dimethyl trisulfide reached 195ng/L and 2-methylisoborneol was not detected.6 The SPME-GC/MS method for determining geosmin,2-methylisoborneol and dimethyl trisulfide by this study is easy to operate,quick to analysis,accurate to quantify,and verified by the investigated water samples,the characteristics of the method is in line with the requirements of the analysis of actual water samples.7 The SPME-GC/MS method established by this study is practicable,and it meets the research objectives of study design.更多还原