| 题名 | 新型卤代有机污染物六氯丁二烯、多氯萘的环境赋存和全氟化合物膳食暴露的初步研究 |
| 作者 | 张海燕 |
| 学位类别 | 博士 |
| 答辩日期 | 2014-05 |
| 授予单位 | 中国科学院研究生院 |
| 授予地点 | 北京 |
| 导师 | 江桂斌，刘稷燕 |
| 关键词 | 持久性有机污染物 六氯丁二烯 多氯萘 全氟化合物 赋存现状 风险评估 Persistent organic pollutants hexachlorobutadiene polychlorinated naphthalenes perfluoroalkyl and polyfluoroalkyl substances occurrence risk assessment |
| 其他题名 | A preliminary investigation of emerging halogenated organic compounds (hexachlorobutadiene and polychlorinated naphthalenes) in the environment and dietary exposure to perfluorinated compounds |
| 学位专业 | 环境科学 |
| 中文摘要 | 三类新型卤代有机物六氯丁二烯（Hexachlorobutadiene, HCBD）、多氯萘（Polychlorinated naphthalenes, PCNs）和全氟化合物（Perfluoroalkyl and polyfluoroalkyl substances, PFASs）是全球普遍存在的持久性有机污染物质（Persistent organic pollutants, POPs）。其中全氟辛烷磺酸及其盐类和全氟辛基磺酰氟作为新型POPs于2009年被增列入斯德哥尔摩公约控制名单，HCBD和PCNs在2011年被列为POPs候选物质。本论文综述了这三类物质的国内外最新研究进展，并针对我国环境中其赋存状况、污染来源及人体暴露风险等进行了初步研究，以期为履约工作提供基础数据。具体研究内容主要包括以下三个方面： 一、率先建立了通过加速溶剂萃取法提取、硅胶和弗洛里硅土复合柱净化、气相质谱联用分离检测土壤和污泥中六氯丁二烯、1,2,4-三氯苯、1,2,4,5-四氯苯及六氯苯的分析方法。方法检出限、回收率以及重复性均满足分析测定的要求。采用该方法分析了我国24个城市37个污水处理厂污泥和江苏一化工企业周边17个土壤样品中HCBD含量。我们同时也测定了样品中三种氯苯物质水平以便更好地了解HCBD的环境行为。污泥中HCBD浓度在< 0.03-74.3 ng/g干重范围内，中值为0.30 ng/g干重，低于所测氯苯物质水平。污泥中HCBD含量与污水处理厂的处理能力以及样品有机碳总量无关。 相比我国其它地区，东部沿海城市污泥中HCBD浓度较高。对于土壤样品，HCBD浓度在厂内土壤中较高，随离工厂距离的增加呈迅速降低的趋势。六氯丁二烯作为氯化物生产时的副产物被无意识生产和释放，这可能是所研究区域环境中HCBD的主要来源。进一步风险评估结果表明厂内土壤生物和工人通过土壤途径暴露HCBD的生态及健康风险较低。 二、采用同位素稀释高分辨气相色谱-高分辨质谱联用技术（HRGC/HRMS）分析了我国典型地区30个污水处理厂污泥中多氯萘的水平、组成以及空间分布特征。污泥中Σ75PCNs浓度范围在1.05-10.9 ng/g干重之间，平均值为3.98 ng/g干重，相比较国外同类样品处于较低水平。一氯萘到四氯萘是主要成分，约占多氯萘总量的85%。二恶英类多氯萘同系物总毒性当量（toxic equivalent quantities, TEQs）在0.04-2.28 pg/g干重范围内，低于我国污泥农用时的最大可接受二恶英类物质TEQ值。我国东部发达城市污水处理厂污泥样品中PCNs及其TEQs浓度相对较高，暗示了PCNs污染水平可能与当地经济发展水平有关，但仍需进一步的研究证实这一结论。工业源是我国污泥中PCNs的重要来源之一。 三、分析了浙江钱塘江沿岸和湖北氟化工厂周边农作物、肉类、肝脏、蛋类和鱼类等228个样品中16种全氟化合物的浓度水平和分布特征，并结合膳食结构评估了人体膳食暴露PFASs风险。结果表明，点源周边样品中PFASs整体水平显著高于产品应用地区，组成类型不同。湖北氟化工厂周边居民膳食摄入PFASs平均水平达87149 ng/day，短链全氟羧酸（C4-C6）是主要污染物。而浙江钱塘江沿岸居民膳食摄入PFASs量较低，为509 ng/day，长链全氟羧酸（C8-C14）及全氟辛烷磺酸（PFOS）是主要污染物。蔬菜和蛋类是湖北氟化工厂周边人群膳食摄入PFASs和PFOS的主要来源，浙江地区居民PFASs和PFOS膳食摄入则主要来自鱼虾类。这与不同食品中PFASs污染水平和组成，及当地饮食习惯有关。湖北氟化工厂邻近村庄（100 米内）居民膳食暴露PFASs风险显著高于相对偏远地点，其PFOS摄入量（392-1200 ng/kg body weight/day）已超过国际上现有每日耐受摄入量标准（100-300 ng/kg Bw/day）。膳食暴露PFASs无显著性别差异，但年龄差异明显，其中2-7岁儿童膳食暴露PFASs风险最高。此外，短链全氟化合物如PFBA膳食摄入量最高达7947 ng/kg Bw/day，对于这类物质可能引起的健康危害需要引起高度重视。 |
| 英文摘要 | Three groups of halogenated organic pollutants，including hexachlorobutadiene (HCBD), polychlorinated naphthalenes (PCNs) and perfluoroalkyl and polyfluoroalkyl substances (PFASs) are ubiquitous in the environment. At the fourth meeting of the Conference of the Parties of the Stockholm Convention (SC) on Persistent Organic Pollutants (POPs) in 2009, perfluorooctane sulfonic acid (PFOS), its salts and perfluorooctane sulfonyl fluoride (PFOSF) were listed as one of nine additional new POPs. Also, HCBD and PCNs were nominated as POPs candidates in the SC in 2011. In this work, recent development of researches on HCBD, PCNs and PFASs were summarized, and their levels, distributions potential sources and risk in China were investigated to support the implement of the SC. Our research includes three aspects: 1. Analytical methods for HCBD, 1,2,4-trichlorobenzene (1,2,4-TCB), 1,2,4,5-tetrachlorobenzene (1,2,4,5-TeCB) and hexachlorobenzene (HCB) in soil and sewage sludge were developed by using accelerated solvent extraction, gel/Florisil column and gas chromatography-mass spectrometry (GC/MS). Method detection limit, recovery and repeatability were satisfactory for determination. HCBD was determined in sewage sludge from 37 wastewater treatment plants (WWTPs) and 17 soils near a chemical plant in China. Three chlorobenzenes (CBs) were also analyzed for comparison of the environmental behavior with HCBD. Concentrations of HCBD in sludge samples ranged from <0.03 to 74.3 ng/g dry weight (dw) with a median value of 0.30 ng/g dw, which was lower than those of the three CBs. Levels of HCBD were not correlated with capacity of the WWTPs and total organic carbon. HCBD in sewage samples were at relatively higher levels in sludge samples from coastal cities in eastern China than those in samples from other cities in China. For soils, higher level of HCBD was found in the sample within the plant, with a rapid decreasing concentration trend with the increase of distance from the plant. It was suspected that emission as a by-product during manufacturing of chlorinated chemicals was the primary source of HCBD in the studied region. Further risk assessment indicated that the environmental risk of HCBD to soil organisms and the health risk to employees were very low through soil exposure within the plant. 2. The profiles, concentrations and spatial distributions of PCNs in 30 sewage sludge samples from WWTPs in China were analyzed using a high resolution gas chromatography/high resolution mass spectrometer (HRGC/HRMS) method. In a global perspective, PCNs in collected sludge samples in China were generally at the low levels (range 1.05-10.9 ng/g dw with a mean value of 3.98 ng/g dw). The predominant homologues in the sludge were mono- to tetra-CNs, accounting for approximately 85% of total PCNs. Total toxic equivalent quantities (TEQs) of dioxin-like PCN congeners ranged from 0.04 to 2.28 pg/g dw with a mean value of 0.36 pg/g dw, which were lower than the maximum permissible TEQ concentrations in sludge for land application in China. Levels of PCNs and TEQs in sludge were relatively higher in samples from highly industrialized and developed cities in eastern China, implying a possible link between PCN contamination and the local economic development, but more studies are warranted to corroborate this. Industrial sources might be one of the important contributors of PCNs to sewage sludge in China. 3. Levels and distributions of 16 PFASs were investigated in 228 food samples including crops, vegetables, meats, livers, eggs and fishes from villages along Qiantang River in Zhejiang province and those surrounding a PFASs manufacturing plant in Hubei province in China. Daily intakes of PFASs were estimated to further investigate the risk of exposure to PFASs through dietary. The results demonstrated that PFASs in foods from Hubei are significantly higher than that in samples from Zhejiang. Compositions of PFASs were also different between these two regions. In Hubei, short chain PFCAs (C4-C6) were predominant. Average daily intake of PFASs for population surrounding PFASs manufacturing plant were 87149 ng/day. While along Qiantang River in Zhejiang, long chain PFCAs (C8-C14) and PFOS were the main pollutant. Average daily intake of PFASs for population were much lower (509 ng/day). Vegetables and eggs were the main contributors to dietary exposure intake of total PFASs and PFOS in Hubei, respectively. While fish were the mian contributors to dietary exposure intake of both total PFASs and PFOS in Zhejiang. This might be due to different levels and profiles of PFASs in different kinds of foods and local dietary habits. Dietary exposure risk to PFASs for villagers near the PFASs manufacturing plant (less than 100 meter) were notable higher than that for people living farther away, and the estimated daily intake of PFOS (EDIPFOS) of 392-1200 ng/kg body weight/day exceeded the tolerable daily intake by international standards (100-300 ng/kg Bw/day). The dietary exposure levels were similar between male and female whereas there was a different with age. Children (2-7 year) had the highest EDI, which need be cautioned. The risk assessment of short chain PFASs such as PFBA are urgently needed due to the extremely high levels around the point source (EDIPFBA max: 7947 ng/kg Bw/day). |
| 公开日期 | 2015-07-07 |
| 内容类型 | 学位论文 |
| 源URL | [http://ir.rcees.ac.cn/handle/311016/15728]  |
| 专题 | 生态环境研究中心_环境化学与生态毒理学国家重点实验室 |
| 推荐引用方式 GB/T 7714 | 张海燕. 新型卤代有机污染物六氯丁二烯、多氯萘的环境赋存和全氟化合物膳食暴露的初步研究[D]. 北京. 中国科学院研究生院. 2014. |
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