太湖胥口湾表层水和沉积物中多环芳烃的浓度水平及生态风险

李晓静，于玉玲，马莉，曾祥英，余应新，张晓岚,*

1. 上海大学 环境与化学工程学院 环境污染与健康研究所，上海 200444 2. 中国科学院广州地球化学研究所 有机地球化学国家重点实验室，广州 510000



太湖胥口湾表层水和沉积物中多环芳烃的浓度水平及生态风险

李晓静1，于玉玲1，马莉1，曾祥英2，余应新1，张晓岚1,*

1. 上海大学 环境与化学工程学院 环境污染与健康研究所，上海 200444 2. 中国科学院广州地球化学研究所 有机地球化学国家重点实验室，广州 510000

多环芳烃；表层水；沉积物；生态风险；时空变化；太湖

多环芳烃(polycyclic aromatic hydrocarbons，PAHs)是一类由2个及2个以上苯环组成的有机污染物，原型及其衍生物达400多种[1]。具有致癌性的多环芳烃主要集中在4环及以上，其中苯并[a]芘(BaP)被确定为强致癌物质，苯并(a)蒽(BaA)、苯并(b)荧蒽(BbF)、苯并(k)荧蒽(BkF)、二苯并(a,h)蒽(DahA)和茚并(123-cd)芘(IcdP)为极可能的致癌物，它们均具有很强的生态与健康毒性。美国环保局(USEPA)将16种对人体健康危害较大的PAHs列入了优先控制污染物名单[2]。

多环芳烃广泛分布在大气、表层水、土壤和食品等环境介质中。由于具有疏水性和亲脂性，PAHs在水中的溶解性较差，主要被悬浮颗粒物吸附，并可随悬浮颗粒物沉降至沉积物，沉积物中的PAHs经过扰动作用等也能够重新释放进入表层水，成为新的污染源[3]。随着研究工作的广泛开展，不同水环境中PAHs研究也取得巨大进展，积累了大量数据。国内不少地区存在较为严重的PAHs污染[4-7]。总体来说，我国水域环境中PAHs污染分布具有以下特点，港口和河口地区的污染水平较高，而内陆湖泊、河流则呈现相对比较轻的污染状态[8]，水文、气候和地区经济等多种因素均可影响PAHs的污染水平。

太湖是我国五大淡水湖之一，它位于华东地区，濒临苏州和无锡，在长江三角洲流域中占有重要的地位，是无锡等地的饮用水源地[9]。随着经济的快速发展，太湖流域的污染问题引起了学者和政府的关注[10]。Lu等[11]研究了太湖水域的重金属、多氯联苯、有机氯农药和PAHs污染，发现沉积物中的PAHs浓度为24～37 ng·g-1；多氯联苯和有机氯农药的浓度范围分别为1.26～2.41 ng·g-1和0.15～2.06 ng·g-1，远远低于PAHs浓度。太湖的整体污染状况呈现北面高于南面的特点。太湖水域的PAHs生态风险具有地区差异性，梅梁湾因为受到周边化工企业污水排放等的影响，生态风险明显比贡湖和胥口湾高[12]。然而目前还没有关于时间变化的PAHs数据。

为此，本文主要针对太湖胥口湾，采集并检测不同时间段的表层水和沉积物样本，分析胥口湾PAHs污染的时间和空间变化特点，并对该水域PAHs的污染水平进行生态风险评估，以期为太湖的环境调查和环境变化研究提供更多数据参考。

1 材料与方法(Materials and methods)

1.1 试剂和材料

1.2 采样

于2011年5月、8月和10月分3次采集表层水和沉积物样品，采样点位置如图1所示。同时平行采集表层水。表层水经0.45 μm的纤维滤膜过滤以分离出水相和悬浮物，分别测定水相和悬浮相中PAHs的浓度，结果合并作为表层水中PAHs的浓度。

图1 太湖胥口湾的采样位置Fig. 1 The sampling locations in Xukou Bay, Taihu Lake

1.3 样品处理

水相中加入回收率指示物萘-d8、苊-d8、菲-d10、荧蒽-d10、芘-d10、苯并(a)芘-d12、苯并(ghi)苝-d12，用二氯甲烷进行液液萃取，萃取液合并浓缩后用硅胶/氧化铝复合柱(2:1)分离净化。收集80 mL正己烷/二氯甲烷淋洗液(V/V=7/3)，浓缩氮吹定容后，加入内标化合物六甲基苯后进行GC-MS测定。

将分离后的悬浮物冷冻干燥后加入回收率指示物并用二氯甲烷进行索氏抽提。抽提液浓缩后用硅胶/氧化铝复合柱(2:1)分离净化。分离净化和定容过程同水相。

沉积物样品冷冻干燥后研细过筛。称取约10 g样品，加入回收率指示物后进行索氏抽提，收集抽提液并浓缩，分离净化步骤同悬浮物。

1.4 仪器分析

采用Agilent气相色谱质谱联用仪(6890 GC-5975 MSD)分析。色谱柱为HP-5MS毛细管柱(30 m × 0.25 mm × 0.25 μm)；载气为高纯氦，流速1.0 mL·min-1。1 μL无分流手动进样；进样口温度为280 ℃；程序升温如下：柱始温80 ℃，保持2 min，3 ℃·min-1升至180 ℃，5 ℃·min-1升至240 ℃并保持1 min，3 ℃·min-1升至290 ℃，保持2 min。采用EI轰击源，离子源温度230 ℃；选择性离子扫描模式检测；目标化合物通过特征离子和标样保留时间比较定性。

1.5 质量保证与质量控制

水样和沉积物各带1个平行样进行分析，该采样点分析结果取平均值。所有样本的分析过程中均加入了氘代PAHs作为回收率指示物。由于萘-d8的挥发性强，大部分样品中其回收率低于60%，因此本文未报道萘的数据。其他6种指示物苊-d8、菲-d10、荧蒽-d10、芘-d10、苯并(a)芘-d12和苯并(ghi)苝-d12的回收率分别为：(87.5 ± 16.3)%、(97.7 ± 15.4)%、(98.9 ± 15.1)%、(102.5 ± 16.3)%、(112.3 ± 20.0)%和(109.7 ± 21.6)%。

检测限(LOD)以低浓度标样响应值标准偏差的3.36倍计算，定量检测限LOQ以LOD的2倍计。统计分析时浓度在LOD和LOQ之间的以1/2 LOQ作为实际浓度，小于LOD的样品，浓度计为0。使用SPSS 19进行统计分析，统计学显著性为P<0.05。

2 结果(Results)

2.1 浓度水平和组成特征

太湖胥口湾表层水和沉积物中PAHs浓度分别如表1和表2所示。表层水和沉积物中15种PAHs总浓度(15PAHs)的变化范围为7.2～83 ng·L-1和66～620 ng·g-1干重；15种PAHs年均总浓度为29 ng·L-1(表层水)和218 ng·g-1干重(沉积物)。表层水主要的PAHs污染物为PHE、FLA、FLO和PYR，年均浓度分别为7.9、4.6、4.2和2.8 ng·g-1。沉积物中的PAHs主要污染物为FLA、PYR和CHR，年均浓度分别为32、27和26 ng·g-1，PHE和ANT的浓度均小于20 ng·g-1。表层水的苯并(a)芘毒性当量浓度(BaPeq)为0.36～5.6 ng·L-1，沉积物的BaPeq为11～103 ng·g-1干重；其年度平均毒性当量浓度分别为2.4 ng·L-1和28 ng·g-1干重。BaPeq的主要贡献者为DahA、BaP和BaA，沉积物和表层水之间的毒性当量浓度差别高于它们的浓度差别。

表1 胥口湾表层水中的PAHs浓度水平

表2 胥口湾沉积物中的PAHs浓度水平

从毒性当量浓度组成看，5环化合物占总浓度的百分比最高，均大于90% (图2A)。从浓度组成看，表层水中对浓度总量贡献最多的主要是3环化合物，但5月水体样本中浓度百分比最大的是4环化合物，约占总浓度的43% (图2A)。沉积物中百分比最高的是4环化合物，约为44%～48%，和高环化合物(5+6环)的浓度总量相当(图2B)。

2.2 PAHs的时空分布特征

太湖胥口湾的PAHs污染水平随时间而波动(图3A)。丰水期(8月)与平水期(5月)、枯水期(10月)的污染水平具有明显差异(Mann-Whitney U检验，表层水P = 0.01～0.033，沉积物P = 0.000～0.039)。表层水的丰水期浓度明显高于平/枯水期，沉积物的情况刚好相反，丰水期污染水平略低。平水期和枯水期的污染浓度之间无显著性差异Mann-Whitney U检验，表层水P = 0.514，沉积物P = 0.291。

将采样点分成湖区(XK-1，XK-2，XK-3，XK-6和XK-10)和湖岸(XK-4，XK-5，XK-7，XK-8，XK-9，XK-11和XK-12)，比较两者的差别(图3B和图3C)，发现湖区和湖岸的PAHs浓度之间无显著差异，特别是平枯水期的污染浓度之间(独立样本T检验，表层水P = 0.184～0.859，沉积物P = 0.105～0.179)。丰水期沉积物中PAHs的浓度差异性也不大(独立样本T检验，P=0.129)；但表层水的湖区浓度显著高于湖岸(独立样本T检验，P = 0.011)。

2.3 生态风险评估

利用加拿大魁北克省的沉积物质量标准对太湖胥口湾PAHs污染开展初步的生态风险评价。该标准提供了5个浓度阈值，分别为生态效应罕有发生浓度值(the rare effect level，REL)、临界发生浓度值(the threshold effect level, TEL)、偶然发生浓度值(the occasional effect level, OEL)、可能发生浓度值(the probable effect level, PEL)和频繁发生浓度值(the frequent effect level, FEL)[13]。阈值范围分别为REL(3.3～47 ng·g-1)、TEL(5.9～110 ng·g-1)、OEL (21 ～450 ng·g-1)、PEL(89～2 400 ng·g-1)和FEL ( 200～4 900 ng·g-1)。该阈值对每种PAH都有浓度要求，本研究中，沉积物PAHs只要有一种污染物浓度超标即视为污染水平整体超标。3个采样期12个采样点PAHs带来的生态风险评估结果如图4所示。图中可以看出大部分采样点都处于REL～TEL生态风险水平范围内，处于较低的污染水平。但是个别采样点和特定采样期的生态风险略高，个别点主要分布在湖岸地区。XK-8和XK-12更是胥口湾重要的水源地。平水期5月也是PAHs生态风险高的频发期，沉积物PAHs污染水平相对较高。

图2 表层水(A)和沉积物(B)中PAHs的组成分布Fig. 2 Compositions of PAHs in surface water (A) and sediments (B)

图3 PAHs的时空分布特征 注：A，不同采样时间表层水和沉积物中的PAHs浓度；B，不同采样时间湖区和湖岸表层水中的PAHs浓度；C，不同采样时间湖区和湖岸沉积物中的PAHs浓度。Fig. 3 The spatial and temporal distribution characteristics of PAHs Note: A, The concentrations of PAHs in surface water and sediment with different sampling time; B, The concentrations of PAHs in lake and nearshore in surface water with different sampling time; C, The concentrations of PAHs in lake and nearshore in sediment with different sampling time.

图4 沉积物中PAHs生态风险的时空变化特征 注：A，5月；B，8月；C，10月。Fig. 4 The spatial and temporal characteristics of the ecological risk assessment of PAHs in sediments Note: A, May; B, August; C, October.

3 讨论(Discussion)

低中环化合物(3和4环)是表层水的主要PAHs污染物，而沉积物中主要是4环的FLA、PYR和CHR。这种组成分布特征与许多文献结果一致[14-15]。东北浑河沉积物中FLA和PYR的浓度水平较高[14]，渤海沿岸地区的河流PAHs研究结果也是如此[15]。对于PAHs来说，它们的KOW值随环数的增加而增大，高环数化合物在水中溶解度的减小，使得它们主要沉降蓄积在沉积物中，而低环数的PAHs更容易随水相迁移或挥发至大气。

表3 不同地区PAHs污染水平比较

图5 PAHs的来源解析Fig. 5 The source analysis of PAHs

从污染水平来说，太湖胥口湾表层水的PAHs污染水平不高(表3)。太湖胥口湾的污染浓度明显小于中国北部地区诸多河流。如东北松花江表层水的PAHs高达934 ng·L-1，太湖胥口湾的水体平均浓度是它的1/30[16]。长江三峡段和浙江舟山海域的污染程度也高于本研究区域[17-18]。太湖胥口湾沉积物PAHs的浓度水平和千岛湖(258～906 ng·g-1)、鄱阳湖(200～400 ng·g-1)的结果接近[19-20]，与青海湖处于同一数量级但略低[35]。上海东部的滴水湖建成时间只有10多年，湖体沉积物的浓度水平稍低于本研究的数据[22]。与密歇根湖及阿根廷湖相比，胥口湾的整体污染程度是它们的3～30倍[23-24]。胥口湾位于整个太湖流域的东南角，湖面比较开阔；胥口湾靠近太湖风景区，附近工厂和工业排放较少，水域整体的污染水平相对较低。

胥口湾的PAHs污染具有时间差异性。8月为丰水期，全年雨水量较集中于该时期。大量的外来径流输入和大气沉降为湖区环境增加了PAHs输入量，造成表层水浓度的提高。丰水期的风浪潮流作用及船舶运输等造成湖体沉积物的再悬浮，PAHs从再悬浮颗粒上的解吸释放也会提高表层水的污染水平[25]。湖泊沉积物的再悬浮又会影响沉积物，引起丰水期沉积物污染浓度的下降。丰水期湖区和湖岸的空间差异性特点也符合输入和再悬浮过程作用的影响效果。丰水期表层水为湖区大于湖岸；沉积物为湖区略高；而平、枯水期的地区差异性不明显。

特征化合物比值法可对环境PAHs的来源进行解析[25]。ANT/(ANT+PHE)小于0.1通常意味着石油燃料类排放来源，其值大于0.1则主要是燃烧来源的影响；FLA/(FLA+PYR)小于0.5则PAHs主要来源于石油燃料类排放，而大于0.5则主要来源于木材和煤的燃烧[27]。本研究结果显示，表层水的ANT/(ANT+PHE)比值和FLA/(FLA+PYR)比值分别为0.01～0.1和0.52～0.95；沉积物的ANT/(ANT+PHE)比值为0.06～0.24，FLA/(FLA+PYR)比值为0.49～0.82 (图5A)。说明胥口湾表层水中PAHs主要来源于石油和燃烧来源，而沉积物中PAHs主要来源于煤和木材燃烧，这和Shi等[28]的研究结果相同。但是，IcdP/IcdP+BghiP和BaA/BaA+CHR值小于0.2时，则认为是石油类污染，当IcdP/IcdP+BghiP大于0.5或BaA/BaA+CHR大于0.35则认为是燃烧来源[29]。从图5B中可以看出，大部分表层水中的PAHs是石油和燃烧来源的混合，而沉积物中的PAHs可能大部分是燃烧来源，含有少量的混合源，这也与ANT/(ANT+PHE)和FLA/(FLA+PYR)比值分析结果一致。这说明太湖繁荣的水上交通对太湖PAHs的污染有重要贡献。

生态风险评价结果如图4所示，太湖胥口湾沉积物的PAHs污染水平基本处于生态效应罕见发生浓度范围和临界发生浓度范围之间，少部分采样点还达到偶尔发生浓度值，这些点主要集中在湖岸区域，正是由于内陆周边工业企业的发展，PAHs随地表径流排入湖，湖岸地区的生态风险相对高。平水期5月份，PAHs能够较稳定地吸附在沉积物表面，此时的沉积物污染水平相对其他时期较高。但是整体来说，太湖胥口湾的生态风险低。

4 结论(Conclusions)

太湖胥口湾表层水和沉积物中PAHs的污染水平较低。3和4环PAHs是表层水的重要污染物，而4环化合物是沉积物的主要污染物，5环化合物对毒性当量浓度的贡献最大。时间变化而言，丰水期表层水浓度偏高，沉积物浓度较低；平枯水期的差别不显著。不同区域的PAHs污染差异性较小，除丰水期表层水中PAHs的湖区组浓度显著高于湖岸组外，其他情况下湖区和湖岸的污染浓度总体比较相近。PAHs特征化合物比值分析表明，胥口湾沉积物中PAHs主要来源于煤和木材燃烧，表层水则是石油和燃烧的混合源。太湖胥口湾的PAHs污染程度不高，只有湖岸的少部分采样点及平水期5月的生态风险略高，整体处于低生态风险。

[1] Rodrigo S, William O, Martha P, et al. Presence of PAHs in water and sediments of the Colombian Cauca River during heavy rain episodes, and implications for risk assessment [J]. Science of the Total Environment, 2016, 540: 455-465

[2] Fernandez P, Vilanova R M, Martinez C, et al. The historical of record of atmospheric pyrolytic pollution over Europe registered in the sedimentary PAH from remote mountain lake [J]. Environmental Science & Technology, 2000, 34(10): 1906-1913

[3] Yu W W, Liu R, Wang J W, et al. Source apportionment of PAHs in surface sediments using positive matrix factorization combined with GIS for the estuarine area of the Yangtze River, China [J]. Chemosphere, 2015, 134: 263-271

[4] Shi Z, Tao S, Pan B, et al. Partitioning and source diagnostics of polycyclic aromatic hydrocarbons in rivers in Tianjin, China [J]. Environmental Pollution, 2007, 146(2): 492-500

[5] Men B, He M C, Tan L, et al. Distributions of polycyclic aromatic hydrocarbons in the Daliao River Estuary of Liaodong Bay, Bohai Sea (China) [J]. Marine Pollution Bulletin, 2009, 58(6): 818-826

[6] Zhao X S, Ding J, You H, et al. Spatial distribution and temporal trends of polycyclic aromatic hydrocarbons (PAHs) in water and sediment from Songhua River, China [J]. Environmental Geochemistry and Health, 2014, 36(1): 131-143

[7] Ana C R, Julián M B, José L S, et al. Coexisting sea-based and land-based sources of contamination by PAHs in the continental shelf sediments of Coatzacoalcos River discharge area (Gulf of Mexico) [J]. Chemosphere, 2016, 144: 591-598

[8] 程家丽, 黄启飞, 魏世强, 等. 我国环境介质中多环芳烃的分布及其生态风险[J]. 环境工程学报, 2007, 1(4): 138-144

Chen J L, Huang Q F, Wei S Q, et al. Distribution and ecological risk of PAHs in the environmental media of China [J]. Chinese Journal of Environmental Engineering, 2007, 1(4): 138-144 (in Chinese)

[9] Qiao M, Wang C X, Huang S B, et al. Composition, sources, and potential toxicological significance of PAHs in the surface sediments of the Meiliang Bay, Taihu Lake, China [J]. Environment International, 2006, 32(1): 28-33

[10] Zhong W J, Wang D H, Xu X W, et al. Screening level ecological risk assessment for phenols in surface water of the Taihu Lake [J]. Chemosphere, 2010, 80(9): 998-1005

[11] Lu G H, Ji Y, Zhang H Z, et al. Active biomonitoring of complex pollution in Taihu Lake with Carassius auratus [J]. Chemosphere, 2010, 79(5): 588-594

[12] Guo G H, Wu F C, He H P, et al. Characterizing ecological risk for polycyclic aromatic hydrocarbons in water from Lake Taihu, China [J]. Environmental Monitoring and Assessment, 2012, 184(11): 6815-6825

[13] Environment Canada and Ministère du développement durable, de I’ Environment et des Parcs du Québec. Criteria for the Assessment of Sediment Quality in Quebec and Application Frameworks: Prevention, Dredging and Remediation [S]. Québec: Library and Archives Canada Cataloguing in Publication, 2007: 1-39

[14] Liu Z Y, He L X, Lu Y Z, et al. Distribution, source, and ecological risk assessment of polycyclic aromatic hydrocarbons (PAHs) in surface sediments from the Hun River, northeast China [J]. Environmental Monitoring and Assessment, 2015, 187(5): 280-290

[15] Wang Z, Wang Y, Ma X D, et al. Probabilistic ecological risk assessment of typical PAHs in coastal water of Bohai Sea [J]. Polycyclic Aromatic Compounds, 2013, 33(4): 367-379

[16] Zhao X S, Ding J, You H. Spatial distribution and temporal trends of polycyclic aromatic hydrocarbons (PAHs) in water and sediment from Songhua River, China [J]. Environmental Geochemistry and Health, 2014, 36(1): 131-143

[17] Dominik D, Wang J X, Hu W, et al. PAH distribution and mass fluxes in the Three Gorges Reservoir after impoundment of the Three Gorges Dam [J]. Science of the Total Environment, 2014, 491: 123-130

[18] 江敏, 梅卫平, 阮慧慧, 等. 舟山近海水体和沉积物中多环芳烃分布特征[J]. 环境科学, 2014, 35(7): 2673-2679

Jiang M, Mei W P, Ruan H H, et al. Distribution of polycyclic aromatic hydrocarbons in the coastal water and sediments of Zhoushan [J]. Environmental Science, 2014, 35(7): 2673-2679 (in Chinese)

[19] 张明, 唐访良, 吴志旭, 等. 千岛湖表层沉积物中多环芳烃污染特征及生态风险评价[J]. 中国环境科学, 2014, 34(1): 253-258

Zhang M, Tang F L, Wu Z X, et al. Characteristics and ecological risk assessment of PAHs in surface sediments of Qiandao Lake [J]. China Environmental Science, 2014, 34(1): 253-258 (in Chinese)

[20] Lu M, Zeng D C, Liao Y, et al. Distribution and characterization of organochlorine pesticides and polycyclic aromatic hydrocarbons in surface sediment from Poyang Lake, China [J]. Science of the Total Environment, 2012, 433: 491-497

[21] Roozbeh M, Mehdi M, Iraj F, et al. Source identification of polycyclic aromatic hydrocarbons (PAHs) in sediment samples from the northern part of the Persian Gulf, Iran [J]. Environmental Monitoring and Assessment, 2014, 186(11): 7387-7398

[22] Faiqa A, Jabir H S, Riffat N M, et al. Occurrence of polycyclic aromatic hydrocarbons in the Soan River, Pakistan: Insights into distribution, composition, sources and ecological risk assessment [J]. Ecotoxicology and Environmental Safety, 2014, 109: 77-84

[23] Chizhova T, Hayakawa K, Tishchenko P, et al. Distribution of PAHs in the northwestern part of the Japan Sea [J]. Deep Sea Research II, 2013, 86-87: 19-24

[24] Yilmaz A, Karacik B, Henkelmann B, et al. Use of passive samplers in pollution monitoring: A numerical approach for marinas [J]. Environment International, 2014, 73: 85-93

[25] 王晓慧, 毕春娟, 韩景超, 等. 再悬浮过程中河流底泥PAHs迁移与释放[J]. 环境科学, 2014, 35(6): 2185-2192

Wang X H, Bi C J, Han J C, et al. Migration and release of PAHs in river sediments during resuspension process [J]. Environmental Science, 2014, 35(6): 2185-2192 (in Chinese)

[26] Larsen R K, Baker J E. Source apportionment of polycyclic aromatic hydrocarbons in the urban atmosphere:A comparison of three methods [J]. Environmental Science & Technology, 2003, 37(9): 1873-1881

[27] Shao Y X, Wang Y X, Xu X Q, et al. Occurrence and source apportionment of PAHs in highly vulnerable karst system [J]. Science of the Total Environment, 2014, 490: 153-160

[28] Shi L Q, Cheng J G, Wu J J. Polycyclic aromatic hydrocarbons in surface sediments of northern Taihu Lake and the coupling with the environment [C]. Xi'an: Advanced Materials Research, 2011: 706-711

[30] Manodori L, Gambaro A, Piazza R, et al. PCBs and PAHs in sea-surface microlayer and sub-surface water samples of the Venice Lagoon (Italy) [J]. Marine Pollution Bulletin, 2006, 52(2): 184-192

[31] Zhang Y, Yu H J, Xi B, et al. Levels, sources, and potential ecological risks of polycyclic aromatic hydrocarbons (PAHs) in a typical effluent-receiving river (Wangyang River), North China [J]. Arabian Journal of Geosciences, 2015, 8: 6535-6543

[32] Zhang Q, Pei G X, Liu G Y, et al. Distribution and photochemistry of polycyclic aromatic hydrocarbons in the Baotou section of the Yellow River during winter [J]. Archives of Environmental Contamination and Toxicology, 2015, 69: 133-142

[33] Mozeto A A, Yamada T M, Morais C R D, et al. Assessment of organic and inorganic contaminants in sediments of an urban tropical eutrophic reservoir [J]. Environmental Monitoring and Assessment, 2014, 186(2): 815-834

[34] Fehmi K, Laurence A, Agung D S, et al. Distribution and risk assessment of hydrocarbons (aliphatic and PAHs), polychlorinated biphenyls (PCBs), and pesticides in surface sediments from an agricultural river (Durance) and an industrialized urban lagoon (Berre lagoon), France [J]. Environmental Monitoring and Assessment, 2015, 187: 591-596

[35] 郭建阳, 廖海清, 张亮, 等. 青海湖沉积物中多环芳烃的沉积记录[J]. 生态学杂志, 2011, 30(7): 1467-1472

Guo J Y, Liao H Q, Zhang L, et al.The sedimentary records of polycyclic aromatic hydrocarbons in Sediments of Qinghai Lake [J]. Chinese Journal of Ecology, 2011, 30(7): 1467-1472 (in Chinese)

[36] Huang L, Sergei M, Chernyak S A, et al. PAHs (polycyclic aromatic hydrocarbons), nitro-PAHs, and hopane and sterane biomarkers in sediments of southern Lake Michigan, USA [J].Science of the Total Environment, 2014, 487: 173-186

[37] Laitano M V, Castro í B, Costa P G, et al. Butyltin and PAH contamination of Mar del Plata Port (Argentina) sediments and their influence on adjacent coastal regions[J]. Bulletin of Environmental Contamination and Toxicology, 2015, 95: 513-520

[38] 郭雪, 毕春娟, 陈振楼, 等. 滴水湖及其水体交换区沉积物和土壤中PAHs的分布及生态风险评价[J]. 环境科学, 2014, 35(7) : 2664-2671.

Guo X, Bi C J, Chen Z L, et al. Distribution and ecological risk assessment of PAHs in sediments and soils in Dishui Lake and its water exchange zone [J].Environmental Science, 2014, 35(7) : 2664-2671 (in Chinese)

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The Contamination Levels of Polycyclic Aromatic Hydrocarbons in Surface Water and Sediments in Xukou Bay of Taihu Lake and the Associated Ecological Risk

Li Xiaojing1, Yu Yuling1, Ma Li1, Zeng Xiangying2, Yu Yingxin1, Zhang Xiaolan1,*

1. Institute of Environmental and Chemical Engineering, Environmental Pollution and Health Research Institute, Shanghai University, Shanghai 200444, China 2. State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510000, China

Received 6 December 2015 accepted 29 January 2016

Polycyclic aromatic hydrocarbons (PAHs), a class of condensed ring compounds, are widely detected in various environmental matrices. Because of their adverse effects on human health and ecological environment, 16 PAHs were listed as priority controlled pollutants by the United States Environmental Protection Agency. Studies showed that PAHs were the main contaminants in Taihu Lake. It is important to investigate the quality of water in Taihu Lake where is an important hydrographic net and urban drinking water supply in East China. The investigation is also very important to improve the aquatic ecosystem qualities and human health of the coastal residents. In the present study, the spatial and temporal variations of PAHs in surface water and sediments in Xukou Bay, Taihu Lake, were investigated. The results showed that the total concentrations of PAHs ranged from 7.2 to 83 ng·L-1for surface water, and from 66 to 620 ng·g-1dry weight for sediments. The average annual concentrations of PAHs in the two matrices were 29 ng·g-1and 218 ng·g-1dry weight, respectively. The mean benzo(a)pyrene toxicity equivalent concentrations (BaPeq) were 2.4 ng·g-1and 28 ng·g-1dry weight in them, respectively. The main pollutants were fluoranthene, pyrene, and chrysene in sediments, while benzo(a)pyrene and dibenz(a,h)anthracene were the most abundant compounds when BaPeqwas considered. The concentrations of 4-ring PAHs accounted for 44%～48% of the total PAHs in sediments, and 5-ring compounds contributed to more than 90% of the total BaPeq. The ratio analysis of the characteristic PAHs showed that PAHs in sediments in Xukou Bay are mainly from burning coal and wood, while PAHs in surface water mainly have fossil fuel and combustion sources. Relatively higher concentrations in surface water and lower concentrations in sediments were observed during the flood season (August). There was no significant difference of the PAH contamination between dry season and ordinary level season. According to the Canadian sediment environmental quality standards, the ecological risks of PAHs in Xukou Bay were low. The spatial and temporal ecological risks showed that the locations with higher ecological risks were mainly at the nearshore. Higher ecological risks of PAHs in sediments might be observed during the ordinary level season (in May), generally.

polycyclic aromatic hydrocarbons; surface water; sediments; ecological risk; spatial and temporal variation; Taihu Lake

10.7524/AJE.1673-5897.20151206002

国家自然科学基金项目(21277087)；中科院重点实验室开放基金(SKLEAC201411)

李晓静(1990-)，女，研究生在读，研究方向有机污染物迁移转化行为研究，E-mail: lxj1123@shu.edu.cn

*通讯作者(Corresponding author)， E-mail: zhangxiaolan@staff.shu.edu.cn

2015-12-06 录用日期：2016-01-29

1673-5897(2016)2-547-09

X171.5

A

简介：张晓岚(1967—)，女，博士，副教授，主要研究方向环境污染分析，发表学术论文30余篇。

李晓静, 于玉玲, 马莉, 等. 太湖胥口湾表层水和沉积物中多环芳烃的浓度水平及生态风险[J]. 生态毒理学报，2016, 11(2): 547-555

Li X J, Yu Y L, Ma L, et al. The contamination levels polycyclic aromatic hydrocarbons in surface water and sediments in Xukou Bay of Taihu Lake and the associated ecological risk [J]. Asian Journal of Ecotoxicology, 2016, 11(2): 547-555 (in Chinese)