【作者】 王德庆；

【导师】 吴明红； 余应新；

【作者基本信息】 上海大学 ， 环境工程， 2013， 博士

【摘要】 多环芳烃（PAHs）和有机氯农药（OCPs）属于典型的持久性有机污染物，具有环境持久性、生物富集性、生物毒性和长距离传输性等特点。由于这类污染物具有较强亲脂性，所以它们容易在生物体富集，并通过食物链放大。在食物链中，鱼类处在较高的营养级，从而增加了其在水生环境中对污染物的暴露水平，因而体内含有高浓度的污染物。在世界范围内，许多研究己经报道了鱼体内含有高浓度的环境污染物，其中包括有机氯化合物、多环芳烃和金属元素，并指出它们可能对人体健康产生威胁。饮食是人体暴露于这类污染物的主要来源之一。太湖是我国的第二大淡水湖，也是我国重要的渔业基地，但对于该湖区鱼体中PAHs和OCPs在鱼类的暴露水平和分布特征的报道很少。本文首先于2009年采集研究了太湖地区24种鱼类，共193个样品中15种PAHs及20种OCPs的浓度分布和污染特征，初步讨论了鱼体内PAHs和OCPs的生物放大现象以及不同营养级的鱼体中PAHs和OCPs的污染特征。结果表明，所有的样品中都检测到了PAHs和OCPs，总的平均浓度范围分别为289–9500ng/g脂重和121–904ng/g脂重。PAHs和OCPs的最低浓度均是在乔丁鱼中发现，最高浓度分别在鲶鱼和长春鳊中发现。与国内外其它地区相比处于中等污染水平。在15种PAHs中，菲是主要的同系物，占∑PAHs总量的45.8%，其次为荧蒽、芘和芴等。∑PAHs主要由低分子量的三环PAHs，如菲、芴、荧蒽和芘等组成，占∑PAHs总量的63.0%。在OCPs中，DDTs和HCHs分别占总OCPs的82.8%和7.4%，p,p’-DDE是DDTs最主要的化合物，占总DDTs的88.1%；β-HCH是HCHs最主要的异构体，占总HCHs的90.8%。通过对太湖鱼体中PAHs和OCPs的来源解析，太湖鱼体中的PAHs可能主要来源于石油的不完全燃烧和煤的燃烧，OCPs主要是由历史残留造成。PAHs和OCPs的生物放大因子（TMFs）范围分别是0.91–1.90和0.83–2.49。鱼体内PAHs和OCPs的浓度会随着鱼体所在营养级的增加而增加，与低营养级的鱼类相比，高营养级的鱼体内含有更高浓度的污染物。从营养级的角度研究了食用太湖不同营养级鱼类给人体健康带来的风险。人体健康风险评估显示成人的日摄入量和风险值会随着鱼体所在营养级的增加而增加，与低营养级的鱼类相比，高营养级的鱼类带来的相对健康风险可能会更高。在此基础上于2010年采集了太湖9种（团头鲂、长春鳊、鲫鱼、鲤鱼、白鲢、花鲢、黄颡鱼、花鱼骨和翘嘴红鲌）常见鱼类，测定了9种鱼类鱼体混合肌肉及4种鱼类（鲤鱼、白鲢、花鲢和翘嘴红鲌）不同部位肌肉内DDTs和HCHs的含量及其同系物的分布特征。并对食用鱼体不同部位肌肉的健康风险进行了评估。九种太湖鱼类混合肌肉中DDTs和HCHs浓度范围分别为786–3389pg/g湿重和63.7–300pg/g湿重，与2009年采集的样品相比，两种污染物的浓度均略有降低。四种鱼类中3个不同部位（背、腹、尾）的肌肉样品中DDTs和HCHs浓度差别较大，这与不同部位的脂肪含量及污染物的亲脂性差异有关，4种鱼类的背部肌肉样品中DDTs和HCHs的平均浓度最低；DDTs浓度最高出现在尾部肌肉中，HCHs浓度最高出现在腹部肌肉中。人体健康风险评估显示除翘嘴红鲌外，食用其它太湖鱼类分部位肌肉不会带来致癌性的健康风险；食用太湖鱼类不同部位肌肉不会带来非致癌性健康风险。对食用9种太湖鱼类混合肌肉及4种鱼类不同部位肌肉时，其营养物二十碳五烯酸（eicosapentaenoic acid, EPA）和二十二碳六烯酸（docosahexaenoicacid, DHA）和污染物（DDTs、HCHs、多氯联苯（PCBs）和多溴联苯醚（PBDEs））共摄入的益害风险进行评估。结果表明，在保证EPA+DHA每日摄入250mg的要求下，食用大部分混合肌肉或分部位肌肉鱼样，均会引起致癌性和非致癌性健康风险，混合肌肉鱼样中健康风险最小的为鲢鱼，分部位肌肉中背部肌肉的健康风险低于腹部和尾部肌肉的健康风险。更多还原

【Abstract】 Polycyclic aromatic hydrocarbons (PAHs) and organochlorine pesticides(OCPs), are a class of persistent organic pollutants (POPs), which are generallycharacterized by properties of persistence, bioconcentration, toxicity and along-range global transport. Because of their high lipophilicity, PAHs and OCPs arecapable of bioconcentration and biomagnification through food chains. Fish oftencontain high contaminant concentrations due to their relatively high position in thefood chain and consequent elevated exposure levels in the aquatic environment.Many investigations have reported high concentrations of environmentalcontaminants including a suit of organochlorine compounds, polycyclic aromatichydrocarbons and metals in fish all over the world, and suggested that they may posea health risk to human body. Diets are one of the major sources of PAHs and OCPsexposed to human.Taihu Lake is the second largest lake in China, and also is an important fisherybase. However, reports on PAHs and OCPs in fish from the lake were limited. In thisstudy, the concentrations of15PAHs and20OCPs were determined in193samplesof24fish species collected from Taihu Lake in2009. The biomagnification of PAHsand OCPs in these fish species were investigated. The results showed that PAHs andOCPs could be detected in all samples, with an average total concentration of PAHsand OCPs in each species ranging from289to9500ng/g lw and from121to904ng/g lw, respectively. The lowest concentrations of PAHs and OCPs were observedin S. dabryi, and the highest were observed in S. asotus and P.pekinensis,respectively. Compared with those in wild freshwater fish from other water bodies inChina and some other countries, fish in Taihu Lake are moderately contaminated byPAHs and OCPs.Among the15PAHs, phenanthrene was the predominant congeners, accountingfor45.8%of the total PAH, followed by fluoranthene, pyrene, and fluorine. The PAH fingerprints were dominated by the lower molecular weight hydrocarbons withtricyclic PAHs being the most abundant, which accounted for63.0%of the totalPAHs. Among the OCPs analyzed, DDTs and HCHs were predominant in all thesamples, which contributed to82.8%and7.4%of the total OCPs, respectively.Among DDT and HCH isomers, p,p’-DDE and β-HCH was respectively the mostaboundant congener of DDTs and HCHs, which accounted for88.1%and90.8%ofthe total DDTs and HCHs, respectively. According to molecular ratios of individualPAHs and OCPs, it indicated that PAHs were mainly originated from both unburnedpetroleum and combustion of fossil fuels, while DDTs and HCHs were mainly agedresidues. The trophic magnification factor (TMFs) of individual PAHs and OCPscongeners ranged from0.91to1.90and from0.83to2.49, respectively. Comparedwith fish at lower trophic position, fish at higher trophic position had relative highercontaminant concentrations. On the basis of trophic levels, the potential humanhealth risks posed via fish consumption were assessed. The daily intake and hazardquotient increased with the trophic levels increasing. Compared with fish at lowertrophic position, fish at higher trophic position had relative higher health risks.In2010, we sampled9species fish from the lake. The whole-muscles (mixedmuscle including dorsal, ventral, and tail muscles) of the nine species (includingWuchang bream, white amur bream, crucian carp, common carp, silver carp, bigheadcarp, yellow catfish, spotted steed, and topmouth culter), and the portion-musclesfrom three portions (i.e., dorsal, ventral, and tail muscles) of4fish species (includingsilver carp, bighead carp, common carp, and topmouth culter) were used to measurethe concentrations of DDTs and HCHs. A total of123samples including55whole-muscle samples and68portion-muscle samples were analyzed. Theconcentrations of DDTs and OCPs in mixed muscle of nine species fish ranged fromranged from786to3389pg g-1ww, and from67.3to300pg g-1ww, respectively.Compared with samples collected in2009, the total concentrations of DDTs andHCHs in the present study were slightly lower. The significant differences of theconcentrations of DDTs and HCHs in three portions (i.e., dorsal, ventral, and tailmuscle) of four species were caused by the lipid contents and hydrophobic property of contaminants. The concentrations of DDTs and HCHs were lowest in dorsalmuscle among three portions. The concentrations of DDTs were highest in tailmuscle, and the concentrations of HCHs were highest in ventral muscle.The potential human health risks posed via fish consumption were assessed.The results showed that consumption most of the portion-muscles of the fish couldnot cause cancer and non-cancer risks except for the ventral and tail muscles oftopmouth culter. The benefit-risk of co-ingestion of eicosapentaenoic acid (EPA) anddocosahexaenoic acid (DHA), and contaminants (DDTs, HCHs, polychlorinatedbiphenyls(PCBs) and polybrominated diphenyl ethers (PBDEs)) was evaluated viaconsumption of fish from Taihu Lake. The benefit-risk quotient (BRQ) wascalculated. The results suggested that to achieve the recommended EPA+DHAintake of250mg d–1for a healthy adult, the consumption of most fish species fromthe lake can cause cancer and non-cancer risks. The results also suggested that therisk of consuming silver carp was generally lower than other fish species, and thoseof dorsal muscles were lower than ventral and tail muscles.更多还原