太湖流域水源地多环芳烃分布、溯源与生态风险评估

利用GC-MS对太湖流域水源地多环芳烃(PAHs)的浓度水平进行监测分析。结果表明,3月水相、悬浮颗粒物和沉积物中PAHs的质量浓度分别为63.5~393.9 ng/L、167~4 358.2 ng/g和940.8~7 398.3 ng/g,分别远高于6月的21.1~64.6 ng/L、125.6~282.3 ng/g和337.3~1 318 ng/g。不同月份单体PAH浓度水平差异较大,可能受控于污染物来源、径流稀释和水动力条件的差异性。特征比值判源结果表明,6月水相和悬浮颗粒物中PAHs主要来源于石油类泄漏和燃烧过程,而沉积物中PAHs在3月和6月均体现为混合源。生态风险评估结果表明,水相、悬浮颗粒物和沉积物中PAHs的生态风险较小,但个别样点单体PAH的含量高于基于生物影响试验的风险评价低值ER-L和ISQV-L,说明存在一定的健康风险,需引起重视。     

深圳近岸海域表层沉积物中多环芳烃分布特征及源解析

利用气相色谱-质谱法(GC-MS)对深圳近岸海域16个监测站位的表层沉积物中16种优先控制多环芳烃(PAHs)浓度进行监测,探讨了深圳近岸海域PAHs的分子组成和分布特征,分析了表层沉积物中PAHs的主要来源。结果表明,深圳近岸海域表层沉积物中16种PAHs总浓度为13 930.00 ng·g~(-1),平均浓度为870.65ng·g~(-1)。沉积物中PAHs以3~5环为主;通过比值法分析得出,深圳近岸海域PAHs污染源为生物质及化石燃料燃烧形成的燃烧来源。     

舟山岛水库有机农药和抗生素残留特征及潜在风险评估

以舟山岛城北、虹桥和岑港3个水库及其周边区域为研究对象,对其表层水样、沉积物及周边土壤中有机农药和抗生素进行了监测和潜在风险评估。结果表明,3个水库表层水样中有机农药质量浓度为43.40～190.40 ng／L,平均值为105.74 ng／L,其中有机磷农药所占比例较大;在土壤及沉积物中有机农药的质量比为0.35～7.76 ng／g,平均值为4.32 ng／g,以有机氯农药污染为主。总体上岑港水库有机农药污染较为严重(水样质量浓度和沉积物质量比分别为 ρ =190.40 ng／L, w =7.76 ng／g),其次为虹桥水库( ρ =110.50 ng／L, w =6.30 ng／g),污染较轻的是城北水库( ρ =59.20 ng／L, w =4.35 ng／g)。抗生素在表层水样中的质量浓度为0.00～64.50 ng／L,平均值为22.30 ng／L,污染相对较轻;在土壤及沉积物中有机农药的质量比为13.50～101.70 ng／g,平均值为62.62 ng／g,处于中等污染水平,其中浓度相对较高的呋喃唑酮应当引起注意。建议构建植物缓冲带拦截和减少周边土壤径流中携带的有机农药和抗生素污染。     

深圳近岸海域表层沉积物中PAHs的风险评估研究

研究深圳近岸海域沉积物中PAHs浓度分布特征,采用人体暴露风险评价方法进行人体健康风险评估和开展生态风险评估。研究结果表明:深圳近岸海域沉积物中PAHs浓度分布范围为200~4 000 ng·g-1,不会产生明显的非致癌健康影响;深圳海域16个采样点沉积物中的PAHs经过监测分析,其中2个站位具有致癌风险,其余站位的非致癌风险在可接受水平;致癌风险和非致癌风险的评价结果均表明深圳近岸海域的生态风险可能性小,但是在部分采样点监测出茚并芘(In P)无最低限值。     

广西北部湾海洋环境与生物体内重金属研究进展

为全面了解广西北部湾重金属污染状况,搜集了近年来有关广西北部湾海水、沉积物及生物体内7种重金属的相关研究成果,比较分析了海水、沉积物中重金属的污染水平及空间分布,探讨了生物体内重金属的污染水平和富集、积累情况,并对海水、沉积物及生物体内7种重金属进行了污染评价,结果表明:①海水中Cu、Zn、Cd、Cr、As含量均符合第一类海水水质标准,与中国其他海域相比各重金属总体处于较高水平,且除Hg外均满足渔业水质标准;②沉积物中各重金属与中国其他海域相比总体处于较低水平,均满足一类海洋沉积物质量标准,Hakanson潜在生态风险评价结果显示,Zn、Cr、Pb、Cu、As、Hg均呈低生态风险,重金属的潜在生态风险顺序CdHgAsPbCuZnCr,多种重金属的综合潜在生态风险指数在防城港、钦州、北海海域均小于150,呈低生态风险;③生物体内重金属基本满足海洋生物质量二类标准,Cd、Cu、Pb均出现大于国家食品卫生标准;④不同生物体对重金属的生物积累作用不同,对重金属的富集能力也不同。广西北部湾海洋环境及生物体已受到一定程度重金属污染,应及时采取防治策略,避免先污染后治理。     

佳木斯土壤多环芳烃残留特征及健康风险评价

选取USEPA优控的16种典型PAHs为研究对象,用索氏提取和GC/MS联用技术分析了PAHs在佳木斯段松花江沿岸土壤中的残留情况,并探讨了该区土壤中PAHs的可能来源及对人体造成的健康风险。GC-MS的仪器的最低检测限为0.01~0.15 ng/g,方法检出限为0.96~190.43 pg/g,相对标准偏差为3.3%~15.1%,16种PAHs的加标回收率在63.78%~96.68%之间,可以满足PAHs的痕量分析要求。研究结果表明,16种PAHs均有不同程度的检出,∑PAHs残留量在2.76~2930.75 ng/g之间,平均值为970.14 ng/g,与国内其余地区相比,处于中等残留水平。研究区PAHs的来源解析表明,PAHs主要来自于化工燃料、煤等燃烧源。利用健康风险评价模型对土壤中PAHs所致健康风险的评价结果表明,佳木斯段土壤样品的PAHs的非致癌风险指数在0~0.174之间,远低于1,均未超标;PAHs的致癌风险度在5.68×10-8~4.91×10-4之间,最大值为4.91×10-4,目前研究区土壤中PAHs类污染物对人体产生的健康风险处于相对较低水平。     

汾河流域沉积物中多氯联苯的分布及生态风险评价

对汾河流域沉积物中国际公认的7种指示性多氯联苯(PCBs)的质量浓度进行测定,分析其组成、空间分布、可能的污染源和生态风险。结果表明:7种PCBs全部被检出,水相PCBs的质量浓度范围为0. 008~0. 485μg/L,沉积相PCBs的质量比范围是4. 44~79. 42 ng/g;沉积相PCB28和PCB180的平均质量比和检出率均比较高,是汾河流域沉积物中的优势污染物,其空间分布表现为从上游到下游干流PCBs质量比先升后降的趋势,PCBs主要来自汾河流域中下游地区分布的大量工业企业及工业园区的排放,汾河流域中游沉积物PCBs的生态风险较高,上游和下游沉积物PCBs的生态风险较低。     

长江口及近海区沉积物重金属与底质环境评价

为了评价长江口及毗邻海域重金属环境污染情况,用评价区49个站位的实测资料对表层沉积物重金属含量与分布变化情况进行了分析。结果表明：调查海域中,沉积物中锌的含量最高,其次为铜、铅,而汞的含量最低,且铜和锌具有明显的线性相关关系;重金属含量分布呈南高北低（特别是调查区东北部）、近岸高远岸低的特征,高值区不仅出现在长江口水质浑浊水域,也出现在杭州湾湾口海域,杭州湾可能已经成为长江口海域重金属元素的另一重要的沉积“汇”。长江口及邻近海域表层沉积物中重金属元素含量整体上呈逐步降低的趋势,2005年沉积物各项指标均符合国家《海洋沉积物质量》一类标准,原因可能是三峡工程蓄水和近年来流域及河口的治理。     

黄河中下游水体中有机氯农药含量与分布

为了解黄河中下游水体中有机氯农药的含量、分布规律及其来源,采用电子捕获检测器检测了黄河中下游干支流26个水样.结果表明:水相OCPs的总含量为2.66～109.55 ng/L,其中HCB、DDTs与HCHs的含量较高,分别为0.25～56.83 ng/L、0.06～10.84 ng/L 和0.73～48.09 ng/L;支流污染较干流严重.悬浮相OCPs的含量为6.30～698.05 ng/g,主要组分DDTs和HCHs的含量分别为2.39～469.28 ng/g和1.30～187.12 ng/g.工业废水和受污染严重支流的汇入、农药的长期使用是黄河中下游有机氯农药污染的主要原因.     

饮用水常规处理工艺对多环芳烃去除的影响

采用固相萃取(SPE)前处理技术和气-质联用(GC-MS)分析方法,定性定量分析南京某水厂常规处理工艺各单元中多环芳烃(PAHs)的种类和浓度。结果表明:过程水和排泥水中均检出10种PAHs(除出厂水中未检出),其总质量浓度分别为97.05～216.85 ng/L和[JP2]98.60～188.89 ng/L;混凝沉淀池和滤池对PAHs的去除率分别为39.28%和12.25%,加氯使芴、菲、苯并(a)蒽和苯并(b)荧蒽的浓度增加;出厂水经管网到达用水点后,各单体芳烃的浓度比例发生显著改变。     

Biomonitoring of polycyclic aromatic hydrocarbons on hepatocellular carcinoma cell line.

Polycyclic aromatic hydrocarbons (PAHs) are not easily degradable and exist as persistent contaminants in water environments. In this study we collected surface sediments and water samples from five different ports around Seto Inland Sea during October 2003 to April 2004. Fifteen PAHs were detected by gas chromatography/mass spectrometer (GC-MS). Expression of CYP1A enzymes was measured by a biochemical activation of 7-ethoxy resorufin ortho-deethylase (EROD). Total water PAHs ranged from 2.5 ng/l to 132 ng/l, while sediment PAHs ranged from 296.3 ng/g to 3992.9 ng/g, which indicate low to high level of PAH pollution. Selected isomer ratios (fluoranthene/pyrene to phenanthrene/anthracene and, total molecular weight of 202/total molecular weight 202-278), and detected PAHs suggested that the origin of pollution could mostly be pyrogenic. The highest total sediment PAHs were observed at the Uno Port while the lowest were at the New Okayama Port. EROD activity implied that PAH extracted from sediment samples affected on CYP1A enzymes expression on the human hepatocellular carcinoma cell line in a short exposure time (12 hours). Relatively EROD activity showed good correlation between PAH concentration and CYP1A expression for sediment samples. The highest EROD values were observed for sediment samples at a dose of 5 ppm. In contrast water samples were at the low induction level even under the highest exposure concentration (50 ppm), except in Mizushima Port. Biomonitoring of water environments by EROD activity could be a necessary tool for understanding the effects of PAHs on living organisms at the base of cell defense.     

Distribution, sources and ecological risks of polycyclic aromatic hydrocarbons in an urban landscape river

The contents of 16 priority water-borne polycyclic aromatic hydrocarbons (PAHs) in water, potential external pollution sources and sediment from the famous landscape of the Qinghuai River were measured by gas chromatography-mass spectrometry (GC-MS). The distribution, composition, source and ecological risk of PAHs were analyzed. The following results were obtained: (1) Benzo[a]pyrene and benzo[ghi] perylene were not detected in all samples. The total contents of 16 priority PAHs (PAH16) varied from 52.5 to 745.3 ng l(-1) with the average of 174.0 ng l(-1) in water, from 96.0 to 1,064.6 ng l(-1) with the average of 329.2 ng l(-1) in potential sources, from 931.7 to 15,295.5 ng g(-1) with the average of 7,133.6 ng g(-1) in sediments. (2) The concentration of PAH16 in water is lower than in sediment and higher rings are more easily detected in sediment. The percentage of higher ring (four- to six-rings) PAHs accounted for more than 55.6% of PAHs in sediment. (3) The value of FLA/(FLA+Pyr) was higher than 0.5 at most sampling points which illustrated the source was related with petrogenic such as liquid fossil fuel combustion. (4) The potential ecosystem risk of low ring PAH for upstream conflux of external Qinhuai River was less than 10%, while it was 10-50% for other sampling points; The four rings PAH shows lower potential ecosystem risk than other ring PAH in this study area; Dibenzo [ah] anthracene (DahA) shows high potential ecosystem risk at all sampling points.     

Occurrence and distribution of organochlorine pesticides and polycyclic aromatic hydrocarbons in surface sediments from Qinghai Lake,northeast Qinghai–Tibet plateau,China

Organochlorine pesticides (OCPs) and polycyclic aromiatic hydrocarbons (PAHs) were analyzed in surface sediment samples collected from Qinghai Lake, the largest lake in China, which is situated in the northeast Qinghai–Tibet plateau at an altitude of 3200 m. The concentrations of these pollutants ranged from 0.02 to 1.00 ng/g for hexachlorocyclohexanes (HCHs), from not detected to 0.86 ng/g for dichlorodiphenyltrichloroethanes (DDTs), from 0.26 to 1.73 ng/g for OCPs, and from 366 to 966 ng/g for PAHs. The predominance of α-HCH suggests that long-range atmospheric transport is an important source for HCHs. A low α- to γ-HCH ratio (3.87 on average) indicates the possible usage of lindane in the drainage basin. The high percentage of p,p′-DDE and p,p′-DDD and the low percentage of o,p′-DDT indicated significant degradation from previous inputs, and no recent inputs of dicofol derived DDT. Based on the analysis of the component ratios, PAHs were found to be primarily from the combustion of biomass and coal-based fossil fuels. Using the Canadian sediment guidelines, PAHs are of greater ecological concern than OCPs in Qinghai Lake.     

PAHs concentration and toxicity in organic solvent extracts of atmospheric particulate matter and sea sediments

The concentration of polycyclic aromatic hydrocarbons (PAHs) and the toxicity to marine bacteria (Vibrio fischeri) were measured for the organic solvent extracts of sea sediments collected from an urban watershed area (Hiroshima Bay) of Japan and compared with the concentrations and toxicity of atmospheric particulate matter (PM). In atmospheric PM, the PAHs concentration was highest in fine particulate matter (FPM) collected during cold seasons. The concentrations of sea sediments were 0.01-0.001 times those of atmospheric PM. 1/EC50 was 1-10 L g(-1) PM for atmospheric PM and 0.1-1 L g(-1) dry solids for sea sediments. These results imply that toxic substances from atmospheric PM are diluted several tens or hundreds of times in sea sediments. The ratio of the 1/EC50 to PAHs concentration ((1/EC50)/16PAHs) was stable for all sea sediments (0.1-1 L μg(-1) 16PAHs) and was the same order of magnitude as that of FPM and coarse particulate matter (CPM). The ratio of sediments collected from the west was more similar to that of CPM while that from the east was more similar to FPM, possibly because of hydraulic differences among water bodies. The PAHs concentration pattern analyses (principal component analysis and isomer ratio analysis) were conducted and the results showed that the PAHs pattern in sea sediments was quite different to that of FPM and CPM. Comparison with previously conducted PAHs analyses suggested that biomass burning residues comprised a major portion of these other sources.     

Fractioning of petroleum hydrocarbons from seeped oil as a factor of purity preservation of water in Lake Baikal (Russia)

Polycyclic aromatic hydrocarbons (PAHs) and n-alkanes were found in five different types of oil-containing samples emanating from deep oil seeps in Lake Baikal, the deepest and oldest lake in the world containing 20% of the world’s surface freshwater. The n-alkanes were the dominant component of the seeped oil on the water surface. PAHs were minor compounds of the oil, but this group is included in a priority series of organic contaminants that are subject to environmental regulation. The set of studied samples from the seep included: (i) freshly-emitted oil on the lake surface, (ii) oil at the lake bottom, (iii) samples of asphalt towers at the lake bottom, (iv) oil from voids within the sediment core and (v) samples of water from different depths. High variability in the concentrations of n-alkanes and PAHs suggested the presence of oil fractionation at the sediment-water interface. A light fraction of oil enriched by n-alkanes migrates to the surface of the lake’s water column, where n-alkanes are biodegraded by the Baikal microbial community while heavy oil fractions remain at the lake bottom and form asphalt towers in which PAHs with maximum toxicity accumulate. In the lake’s photic water layer, PAHs from light oil can be accumulated by phytoplankton. In the lake’s water column, benzo[a]pyrene was not detected over their detection limit (0.1 ng/L). The Toxic Equivalent (TEQ) value of PAHs identified in the Baikal water ranged from 0.001 to 0.012 ng/L.     

Transfer of hydrophobic contaminants in urban runoff particles to benthic organisms estimated by an in vitro bioaccessibility test.

An in vitro bioaccessibility test was applied for assessing the transfer of polycyclic aromatic hydrocarbons (PAHs) present in road dust, into benthic organisms living in a receiving water body. The road dust is supposed to be urban runoff particles under wet weather conditions. Sodium dodecyl sulfate (SDS) solution was used as a hypothetical gut fluid. Pyrene, fluoranthene and phenanthrene were the main PAH species in the SDS extractable fraction of road dust, as well as the whole extract. Benzo(ghi)perylene showed relatively low concentrations in the SDS extract in spite of a high concentration in the original dust. The PAH composition in benthic organisms (polychaetes) did not correspond with that of the surrounding sediment and the PAHs detected were also detected in high concentrations in the SDS extract of road dust. When testing the toxicity of the extracted contaminants by a standardised algal toxicity test, SDS extracts of a detention pond sediment showed higher toxicity than the pore water of the corresponding sediment. Sediment suspension showed a comparative toxicity with 0.1% SDS extract. From the results, the in vitro bioaccessibility test seems more suitable to evaluate the exposed contaminants than the traditional organic solvent extraction method and the SDS extracted fraction is applicable to toxicity tests reflecting the digestive process.     

杭嘉湖地区饮用水源半挥发性有机物污染现状

采用固相萃取-GC-MS法对杭嘉湖地区16个集中式饮用水源水体中的氯代苯、多环芳烃、硝基苯、多氯联苯、邻苯二甲酸酯等43种半挥发性有机物（SVOCs）进行了分析检测。结果表明,16个集中式饮用水源水共检出10余种有机污染物,浓度范围为0.01~4.26μg/L,检出率为5%~100%;邻苯二甲酸二甲酯、邻苯二甲酸二乙酯、邻苯二甲酸二丁酯、邻苯二甲酸双（2-二乙基己酯）、2,6-二硝基甲苯等化合物的检出率为超过50%;在平水期、丰水期、枯水期,被检出的有机污染物种类分别为12,9,14种,被检出污染物的浓度范围分别为0.05~4.26,0.01~0.20,0.01~1.00μg/L。     

北京市北运河流域河水和地下水多环芳烃分布规律及风险评价

为研究北运河流域河水与不同含水层地下水体中多环芳烃(PAHs)的相互作用,收集北运河流域上游温榆河段及下游北运河段不同季节的河水与地下水水质数据,采用对比分析及显著性分析方法研究河水与地下水中多环芳烃的组成、含量及时空分布特征,并利用风险熵法进行风险评价。结果表明:16种优控多环芳烃中,除苯并[a]芘和二苯并[a,h]蒽检出率不足100%外,其余14中多环芳烃污染物在河水、潜水和承压水中均全部检出;多环芳烃总质量浓度的构成以萘为主,质量浓度为1 587.42ng/L,约占总质量浓度的85.6%;潜水和承压水春季多环芳烃总质量浓度显著低于夏季,2～3环多环芳烃质量浓度高于4环以上多环芳烃质量浓度;潜水中多环芳烃总质量浓度高于承压水;北运河段潜水中多环芳烃总质量浓度高于温榆河段;温榆河段地下水主要污染物为萘、芴和菲,北运河段地下水主要污染物为萘、苊和菲;上游河水多环芳烃总质量浓度低于下游,主要污染物为萘和菲;萘、芴、菲、蒽、荧蒽、芘、苯并[a]蒽在不同位置条件下差异显著,除苯并[a]蒽、苯并[b]荧蒽、苯并[a]芘和二苯并[a,h]蒽之外,其余多环芳烃在不同季节条件下均差异显著;通过风险熵法计算得出不同季节和位置条件下研究区生态风险相对较低。     

A novel method for evaluating bioavailability of polycyclic aromatic hydrocarbons in sediments of an urban stream.

Hydrophobic organic pollutants in urban wet weather discharges can accumulate in the sediments of receiving waters and may have adverse effects on the ecological system, especially on benthic organisms. Here, a novel method is developed for evaluating the bioavailability of such hydrophobic organic pollutants by considering the digestive guts in deposit-feeding polychaetes. We compared the amount of polycyclic aromatic hydrocarbons (PAHs) extracted by an organic solvent and by sodium dodecyl sulfate (SDS) solution (as a hypothetical digestive gut fluid of polychaetes) and interpreted the ratio of the two values as bioavailability. The sediment extracts were applied to bacterial acute toxicity tests and algal growth inhibition tests. Sediment samples were collected from an urban stream system receiving wet weather discharges. The bioavailability of the total amount of 12 PAHs in the sediments was in the range 14-38% based on the results from the GC/MS determination of the two different extracts. Lower molecular PAHs showed higher bioavailability compared to the higher molecular ones. The sediment extracts were shown to be toxic towards both algae and bacteria. The SDS extracts showed similar or higher toxicity in the two biotests compared to the organic solvent extracts in spite of their lower PAHs content.