海洋环境中有机锡的形态分析及其代谢降解研究

【作者】 于振花；

【导师】 黄彦良； 王小如；

【作者基本信息】 中国科学院研究生院（海洋研究所） ， 海洋化学， 2009， 博士

【摘要】 有机锡化合物被广泛用作塑料制品中的稳定剂、船舶油漆的防污剂、工业催化剂、农林业杀虫杀菌剂以及用于木材的防腐保存等,已经引起严重的环境污染。世界上许多国家纷纷制定相应的法规对其使用加以禁止或限制。我国目前还没有明确的限制有机锡使用的法律法规,缺少有机锡污染的第一手资料,更没有长期的控制、监测与研究计划。由于有机锡的种类繁多,理化性质存在差别,所以在提取、分离和测定中均存在较大的困难。从我国这方面己有的工作来看,缺乏各种高选择性的分离方法和高灵敏度的检测方法是制约这项研究广泛开展的原因之一。有机锡的痕量与超痕量分析技术是当今环境和食品安全分析领域的前沿技术。本论文利用高效液相色谱和电感耦合等离子体质谱联用技术建立了海洋环境中多种有机化合物的同时快速检测方法;发展了多种海洋环境样品中有机锡的前处理技术;研究了有机锡在海洋生物中的分布、代谢及降解过程中化学形态的变化;同时发展了海洋环境中多种痕量元素的快速检测方法。所建立的高效液相色谱和电感耦合等离子体质谱联用技术可同时、快速分析5种有机锡的形态(三甲基锡TMT、二苯基锡DPhT、二丁基锡DBT、三丁基锡TBT和三苯基锡TPhT),其检出限均低于0.3μg/L。用所建立方法对南海海洋生物样品中的有机锡污染进行了研究,利用SPSS软件对检测结果进行了探讨,发现在所研究海洋生物样品的97.2%中可检出丁基锡和苯基锡化合物,其浓度分布处于该化合物检出限～1487.8ng/g范围内。其中,贝类样品中总有机锡的平均浓度为416.9ng/g,远远高于鱼类样品中总有机锡的平均浓度(211.9ng/g)。海洋生物中存在高浓度的有机锡说明本海域有机锡污染严重,已经对生态环境造成了严重影响,危害到人类生活。其主要的污染源是防污涂料的应用,目前紧迫的问题是采取必要的措施来控制有机锡的使用。本工作建立了海水样品和沉积物样品中五种有机锡的简单快速萃取方法。采用加入2%的环庚三烯酚(tropolone)的二氯甲烷CH2Cl2对海水中的有机锡进行萃取,大大提高了有机锡的萃取率,减少了萃取的时间,二苯基锡(DPhT)、二丁基锡(DBT)、三丁基锡(TBT)和三苯基锡(TPhT)的萃取率均在80%以上,仅三甲基锡(TMT)的萃取率较低(在50%左右),究其原因,可能是因为在萃取的过程中三甲基锡(TMT)产生了降解。采用流动相和0.2%环庚三烯酚酮(tropolone)对沉积物国际标准物质PACS-2进行超声萃取及高速离心后,用所建方法进行了分析。结果表明,测定值与标准值吻合。研究表明,所建立的方法可用于实际环境沉积物中有机锡的形态分析。本文建立了流动注射与电感耦合等离子体质谱联用技术直接同时测定海水中多种痕量元素的方法。该方法采用痕量进样技术,能够有效地减少海水中Na,Mg, Ca和Cl等大量基体元素对待测痕量元素测定的干扰,减少这些元素在电感耦合等离子体采样锥上的盐沉积,可以同时测量海水中的V、Cr、Mn、Fe、Co、Ni、Cu、Zn、As、Mo、Cd、Pb,Hg和U等痕量级元素。用所建的方法测定南海海域海水中的重金属元素,发现Cd,Cr,As等有毒有害元素的污染很轻,均符合Ⅰ级海水的限量。在海洋沉积物样品处理研究中,本工作改进了不需要赶走HF酸就可以对沉积物消解完全的密闭容器消解法,由于减少了赶走HF酸的步骤,使消解的时间由原来的二十个小时降低为十个小时,大大降低了消解的时间。采用该样品消解方法,并用ICP-MS测定了南黄海海域沉积物中锡及其他重金属元素的含量。建立了微波消解-ICP-MS测定海洋生物中锡、砷、镉、汞及铅等有害重金属元素的分析方法,并用于南黄海7个及南海海域29个海产品中的测定。测定结果表明海洋生物中上述有毒有害元素有不同程度的超标问题;不同种类,不同产地的海洋生物中重金属元素的含量有一定的差别,这些研究结果为海产品安全质量控制提供了有价值的科学信息。在上述各章工作的基础上,本文研究了有机锡在海洋生物中的分布、代谢及降解过程,并初步建立了高效液相-电喷雾-飞行时间质谱(LC-APCI-TOF-MS)测定有机锡的方法,可对未知的有机锡化合物进行结构表征。有机锡在贝类中不同的组织显示,其内脏中有机锡的含量高于肌肉中有机锡含量。常规的煮、炸、蒸及微波的烹饪方式并不能降解海产品中的有机锡化合物。更多还原

【Abstract】 Organotin compounds have been widely used as heat and light stabilizers in the production of polyvinylchloride materials, and as anti-bacterial and anti-fungal agents in pesticides and anti-fouling applications. The toxicity of Organotin compounds, especially those of tributyltin and triphenyltin has resulted in deleterious effects on non-target organisms such as shellfish and fish in coastal environments. The bioaccumulation of these compounds in shellfish and fish can result in serious health damage on human who consumed these contaminated species. Many countries around the world have formulated their respective laws and regulations prohibiting or restricting the use.of organotin compounds. Trace and ultra-trace analytical technique for organotin compounds in today’s environment and food safety areas is a kind of cutting-edge technology, as a result of a wide variety of alkyl tin, the existence of differences in physical and chemical properties. There are a large of difficulties in the extraction, separation and determination of organotin compounds in the marine environmental samples. .In the present work, a hyphenated technique of high-performance liquid chromatography (HPLC) coupled with inductively coupled plasma mass spectrometry (ICP-MS) was established for a rapid and simultaneous determination of several important organotin compounds; the sample pre-treatment technology for those organotin in marine environmental samples was developed. The distribution, metabolism and degradation of organotin in marine organisms were characterized primarily, and a rapid detection method for trace elements was established. The five species of organotin was detected rapidly by use of the method developed in the present work. The detection limits of five organotin compounds all are less than 0.3μg/L.The case study forganotin pollution for marine organisms in the Southern Yellow Sea was performed with the method developed in the present work, and a commercial statistical software (SPSS) was applied to analyze the experimental results obtained. It was found that 97.2% of marinounde organisms contained butyltin and phenyltin compounds, and the concentrations ranged from the detection limits of those compounds upto 1487.8ng Sn/g. The average concentration of the total organotin in the shellfish samples was 416.9ng Sn/g, which was much higher than the average concentration of total organotin in the fish samples (211.9ng Sn/g). The fact of organotin with high concentration in marine organisms indicates that the pollution of organotin in this area is serious, which may damage the ecological environment and human life. The main pollution source might be attributed to the application of antifouling paint along the costal. Therefore the critical point is to take the necessary steps of controlling the use of organotin in this area.In order to accurately analyze the seawater and sediment samples, a simple and rapid extraction method for five organotin compounds was established in this study. By adding 2% of tropolone into CH2Cl2, the organotin in seawater samples was extracted with a higher rate. The extraction rate of DPhT, DBT, TBT and TPhT were all more than 80%, while the extraction rate of TMT was only 50%. by using of mobile phase and 0.2% tropolone, the international standards sediment (PACS-2) was analyzed after ultrasonic extraction and high-speed centrifugation, the analytical results illustrate that the experimental data obtained are agree well with the the certified results of the international standard materials. This indicates that the method established could be applied to the analysis of organotin compounds in real marine sediment samples.Meanwhile, a method for direct determination of trace elements in seawater with hyphenated technique of flow injection coupled to inductively coupled plasma mass spectrometry(ICP-MS) was established, which was successfully applied to the case study for the determination of heavy metals in South China Sea. The results showed that the concentrations of Cd, Cr and As in this area are lower than the limits of first-degree seawater of China regulation. The method was characterized with its high efficiency to reduce the interferences from Na, Mg, Ca and Cl in seawater by using the trace sampling technique. The method could also be used to measure trace-class elements including V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Mo, Cd, Pb, Hg and U.A sediment digestion method in closed-vessel without removing HF acid was recommended, which could reduce the sample treatment time from 20 hours to 10 hours. With this digestion method, tin and other heavy metals in the sediment of South Yellow Sea were accurately determined with ICP-MS. The heavy metal pollution history of marine sediments around South Yellow China Sea was surveyed. From which, it was found that the pollution from Cu, Zn, Cr, Ni, Pb, Co and Mn in the sediments had been increased gradually from 2001 to 2007. Also a method of microwave digestion-ICP-MS was established to determine the harmful heavy metals such as tin, arsenic, cadmium, mercury and lead. Seven seafood samples from the Southern Yellow Sea and twenty nine seafood samples from the South China Sea were analyzed. Different degrees heavy metal pollution in seafood could be found. The heavy metal contents in different types and regions were varied, which could provide a useful reference for seafood quality control.The distribution, metabolism and the degradation processes of organotin compounds were studied primarily, and a novel method to characterize organotin compounds.with LC-APCI-TOF-MS was established in this work. The experimental results showed that organotin contents varied in different organs of shellfish samples. Their contents in internal organs were higher than those in muscle. It was recommended that the common cooking methods may not reduce the contents of organotin in sea food.更多还原