长江口崇明渔港表层沉积物中丁基锡赋存特征及生态风险

在长江口及崇明岛沿岸渔港采集表层沉积物样品,通过超声萃取-乙基化衍生技术提取沉积物中的丁基锡化合物,用气相色谱-质谱联用仪分析沉积物中的丁基锡赋存特征。结果显示,在长江口的参考点沉积物中均未发现有机锡化合物,而在各调查的渔港沉积物中均检出丁基锡,总浓度在1.6~58.8 ng Sn·g-1(干重,以下同)之间变化。表层沉积物的三丁基锡(TBT)、二丁基锡(DBT)和一丁基锡(MBT)浓度范围分别为ND~28.7 ng Sn·g-1,ND~22.1 ng Sn·g-1,1.6~8 ng Sn·g-1。其中,堡镇港TBT污染水平最高;老滧港和奚家港口门处沉积物中TBT浓度与新河港差不多(平均为17.2 ng Sn·g-1),而在港口内部沉积物中均未检出TBT,仅有MBT残存。检出TBT的样点,均在大型渔船码头、客运游艇码头或船厂附近,其浓度均超过澳大利亚和新西兰推荐的TBT沉积物质量基准(ISQG)触发值,即5 ng Sn·g-1。同时各样点暴露浓度(PECsed)与预测无效应浓度(PNECsed)的商值均大于1,SQG和PECsed/PNECsed两个方面均反映了崇明岛渔业港口沉积物中的TBT存在生态风险。综上,长江口地区沉积物中有机锡化合物形态和浓度差异很大,码头或船厂附近沉积物中有机锡污染问题值得优先关注。     

通讯

沉积物中有机污染物的生物可利用性的化学测量方法 准确测定疏水性有机污染物（HOCs）的生物可利用性对于评估沉积物生态毒性风险,实施沉积物污染修复极其重要．在研究生物可利用性的理论机制的同时,不少工作也从实践上探索测定生物可利用性的快速有效方法．传统的沉积物生态风险评估,常常运用沉积物中HOCs的有机碳标准化浓度来表征该...     

水生生物毒性测试用于沉积物评价的研究进展

针对沉积物污染问题的研究目前已建立了不同的评价方法与体系,目前常用的结合生物毒性测试的有效应导向分析(EDA)、沉积物毒性鉴别评价(TIE)、证据权重法（WOE）、物种敏感性分布法（SSD）和沉积物质量基准（SQG）等,这些方法在河流、湖泊等水体沉积物中污染物毒性效应表征及沉积物质量评价方面有重要应用.本文指出水生生物毒性测试应用的重要性,根据不同学者的研究内容归纳了水生生物毒性测试的方法学,对沉积物进行水生生物毒性测试的基质处理包括直接采用污染沉积物、洁净沉积物加标以及人工配置沉积物,受试生物主要包括浮游植物、浮游动物、底栖动物和鱼类,毒性试验终点包括急性毒性终点和慢性毒性终点;最后指出水生生物测试存在的问题,并对沉积物质量评价未来发展方向进行展望,以期为我国沉积物生物毒性测试标准方法的建立提供参考.     

生物扰动对沉积物中污染物环境行为与生物可利用性的影响

疏水性有机污染物进入环境水体后易于与沉积物结合,对沉积物中的底栖动物造成危害。底栖动物引起的生物扰动作用可以通过改变沉积物的地球化学性质,对其中污染物的赋存形态、迁移转化和生物可利用性产生重要影响。在综述了国内外生物扰动影响沉积物中污染物环境行为和生物可利用性的最新研究进展基础上,重点讨论了沉积物颗粒交换、水体环境条件改变、疏水有机污染物解吸释放过程以及对生物扰动影响的定量化表征。最后对该研究方向进行了展望,指出应重点研究多种污染物及不同生物共存条件下的生态效应,以及造成沉积物扰动的影响因素的定量化表征等。     

沉积物中有机污染物的生物可利用性的化学测量方法

准确测定疏水性有机污染物(HOCs)的生物可利用性对于评估沉积物生态毒性风险,实施沉积物污染修复极其重要.在研究生物可利用性的理论机制的同时,不少工作也从实践上探索测定生物可利用性的快速有效方法.传统的沉积物生态风险评估,常常运用沉积物中HOCs的有机碳标准化浓度来表征该污染物在生物体内的蓄积量及其对生物体     

广东清远电子垃圾处理地沉积物对伸展摇蚊的慢性毒性效应

电子垃圾拆解引起的环境污染和生态风险已成为全球关注的热点问题,不适当的电子垃圾拆解过程造成处理区水体沉积物受到多类有机化合物和重金属污染,直接威胁生活在沉积物中的底栖动物。在典型电子垃圾处理地广东清远采集沉积物,测定样品中以烃类为主的色谱难分离混合物(unresolved complex mixture,UCM)的含量,开展伸展摇蚊全生命周期慢性毒性测试。结果表明,清远沉积物中的UCM浓度(0.08±0.01)%接近于这类污染物对伸展摇蚊的慢性半致死性效应浓度(0.073±0.022)%。同时发现清远沉积物对以摇蚊为代表的底栖无脊椎动物具有显著慢性毒性效应,且可通过测定UCM含量初步估算。这为开展以电子垃圾处理地沉积物为代表的,受到以麻醉作用为主要致毒机制的混合物污染的沉积物的毒性评价提供了一种有效方法。     

玉米秸秆生物炭对沉积物中BDE-47生态毒性的影响

生物炭对于污染沉积物的原位修复具有很大的潜力,但关于生物炭对沉积物中有机污染物生态毒性影响的研究则较少报道。为评价生物炭对沉积物中BDE-47生态毒性的影响,以底栖动物铜锈环棱螺为测试生物,采用28 d慢性沉积物生物测试研究了不同添加比例的玉米秸秆生物炭(CSB)与BDE-47联合作用对BDE-47生物积累、肝胰脏细胞DNA损伤以及氧化胁迫生物标志物的影响。结果表明,在慢性暴露情况下,CSB对铜锈环棱螺不具有毒性;CSB通过显著降低沉积物间隙水中BDE-47的浓度而降低其在铜锈环棱螺体内的生物积累。在实验浓度范围内(1%～7%),CSB添加比例越高,降低BDE-47生物积累的效果越显著。不同添加比例的CSB均可以显著降低BDE-47对铜锈环棱螺DNA损伤的毒性,较高比例(4%和7%)CSB的效果更为显著,但BDE-47的氧化胁迫毒性不随CSB添加比例的升高而下降。因此,从降低BDE-47生态毒性的角度考虑,沉积物中CSB的合适添加比例为4%左右。     

三丁基锡对中国近海常见海洋微藻的毒性效应

研究三丁基氯化锡（TBT）对中国近海常见5种硅藻和甲藻（硅藻中丹麦细柱藻（Leptocylindrus danicus）、派格棍形藻（Bacilaria paxillifera）、聚生角毛藻（Chaetoceros socialis）,甲藻中微型原甲藻（Prorocentrum minimum）、简裸甲藻（Gymnodinium simplex））的毒性效应,考察了有机锡对浮游藻光合活性（Fv/Fm）、粒径、生长的影响。结果表明：派格棍形藻、聚生角毛藻、简裸甲藻的光合活性（Fv/Fm）受TBT影响较显著;微型原甲藻、丹麦细柱藻的光合活性受TBT影响较小。高质量浓度TBT胁迫下海洋微藻峰值粒径显著减小,低质量浓度TBT对峰值粒径影响不显著。低质量浓度TBT对派格棍形藻、聚生角毛藻、简裸甲藻、微型原甲藻均有较强的毒性作用,非检测毒性浓度（NDEC）分别为1.17、1.07、0.23、3.73μg.L-1,丹麦细柱藻对TBT具有很强耐受性,NDEC为112.62μg.L-1。     

河蚬在我国沉积物毒性评价与鉴定中的应用研究

河蚬作为原产并广泛分布于我国及东南亚的双壳类淡水软体动物,是我国众多水域的底栖优势种。河蚬对水体污染物具有较强累积能力,已成功用于水体沉积物生物富集及生物毒性效应研究。但应用于沉积物毒性鉴别评估(TIE)研究整体上仍处于起步阶段,尚未形成一套标准指标测定方法和技术体系。为此,本研究在调查底栖生物在我国沉积物毒性研究的基础上,以河蚬为主要研究对象,探讨其在我国生态分布等生物学背景,系统分析其对重金属和有机污染物的生物富集特征以及相关生物毒性效应方面的研究进展,以期为河蚬作为我国特色的沉积物毒性鉴别评估(TIE)受试生物提供参考依据。     

澜沧江梯级水电开发对漫湾库区大型底栖动物群落及重金属沉积的影响

梯级水电开发对于河流生态系统具有复杂和深远的影响,大型底栖动物及沉积物可以很好地反映水生态系统的变化及演替趋势。结合澜沧江干流梯级水电开发,分别于2011年和2016年在漫湾库区开展大型底栖动物及沉积物定点采样调查,分析梯级水坝运行对库区大型底栖动物群落结构及生物多样性的影响,采用潜在生态风险指数(RI)对库区沉积物重金属(As、Cd、Cr、Cu、Pb和Zn)的生态风险进行评估,基于CCA和Pearson相关分析研究了大型底栖动物群落与重金属沉积的相互作用关系。结果表明,澜沧江梯级水坝运行后,漫湾库区静水区大型底栖动物群落密度和生物量增加明显,特别是软体动物中的河蚬河蚬(Corbicula fluminea),其密度和生物量在库区静水区占据绝对优势;库区静水区Margalef丰富度指数(d)增加显著,而Shannon-Weaver指数(H′)表现为旱季降低,雨季增加的趋势;库区沉积物重金属主要生态风险来源于Cd,其次为As,重金属潜在生态风险指数(RI)在静水区增加明显,特别是高水位的旱季,而过渡区增加不大;CCA分析表明沉积物中重金属Cr、As、Pb的含量对大型底栖动物群落及物种组成影响较大;Pearson相关分析表明昆虫纲密度与沉积物中Cr的含量呈显著正相关(P0.01),软体动物门密度与Cd、As、Cu、Zn、Pb的含量和重金属潜在生态风险指数(RI)呈显著正相关(P0.01)。随着澜沧江梯级水坝的运行,漫湾库区大型底栖动物群落及沉积物仍处于动态变化过程中,需进行长期的定点监测及深入研究。     

Ecotoxicity studies of some organotin compounds

The ecotoxicities of three organic compounds containing spacer groups, an intermediate organotin premonomer, four organotin monomers, their homopolymers and six copolymers of tributylin α‐chloroacrylate (TCA) are reported against two microorganisms viz., Pseudomonas aeruginosa and Sarcina lutea and a larval species Anemia salina (Nauplii II). The organic compounds containing spacer group were less toxic whereas the monomers were found to be highly toxic. The homopolymers were found to be more toxic than that of tributyltin acrylate (TBTAA), tributyltin methacrylate (TBTMA) and tributyltin α‐Chloroacrylate (TCA). The toxicity of TCA copolymers increased with the increase in tributyltin (TBT) content in the polymer. From this study it was not possible to establish any relationship between the chemical nature of the comonomer with its toxicity.     

Retrospektives Monitoring von Organozinnverbindungen in biologischen Proben aus Nord- und Ostsee – sind die Anwendungsbeschränkungen erfolgreich?

Background, aim, and scope Organotin compounds are used as biocides, plastic additives and catalysts. With respect to environmental effects, tributyltin (TBT) and triphenyltin (TPT) compounds are the most relevant, because of their high aquatic toxicity and endocrine effects on mussels and snails. TBT was mainly used as antifouling agents in coatings of ships and boats. In 1989, Germany banned the application to ships <?25?m length. Finally, in 2003, the use of organotin-based antifoulants within the European Union was completely banned. To verify the effectiveness of the restrictions a retrospective monitoring study was initiated. Material and methods A set of appropriate archived samples was retrieved from the German environmental specimen bank (ESB) comprising standardized pooled samples of eelpout (Zoarces viviparus) muscle tissue and of soft bodies of common mussels (Mytilus edulis) sampled at two locations in the North Sea and one in the Baltic Sea. Analysis of organotin compounds included n-hexane extraction, derivatisation with sodium tetraethyl borate, capillary gas-chromatographic separation and atomic emission detection. Results and Discussion Altogether, time series cover the period 1985 to 2006, including data of an earlier study (Rüdel et al. 2003). Until the late 1990s, TBT remained more or less constant in all samples (e.?g. 17?±?3?ng/g wet weight, ww, in mussels from Jadebay/North Sea). The German ban of TBT-based antifoulings for small ships had no effects on environmental concentrations because large ships dominate in the investigated North Sea regions. After the EU-wide ban of TBT in 2003, however, significant decreases in mussel and fish contamination could be observed. In mussels from Jadebay, TBT concentrations were 14 and 6?ng/g ww in 2004 and 2005, respectively. TBT contamination in eelpout of the same region decreased to about 30 percent of the initial concentrations in 2006. Corresponding decreases were detected for TPT. Declining trends were also found in fish and mussels sampled from a Baltic Sea offshore site. Conclusions The results demonstrate the effectiveness of the legal measures undertaken to control organotin inputs into the aquatic environment. Nevertheless, organotin compounds are still relevant pollutants. Water concentrations calculated from the measured tissue concentrations by using the respective bioconcentration factors are still above the Environmental Quality Standards derived in the context of the Water Framework Directive (0.2?ng/l) and the OSPAR mussel EAC (Environmental Assessment Criteria; 2.4?ng/g ww). Thus adverse effects to marine organisms cannot be excluded. Recommendations and perspectives Further studies should be performed to verify the declining trends. More sensitive analytical methods, e.?g. species-specific isotope dilution analysis, are recommended in order to detect lower environmental concentrations.     

Niche segregation and habitat specialisation of harpacticoid copepods in a tropical seagrass bed

Several harpacticoid copepod species are adapted to an epiphytic lifestyle. Previous studies on tropical seagrass meiofauna mainly focussed on the epiphytic communities and neglected the benthic component. The present study aims to document the benthic harpacticoid copepod communities sampled from different sediment depth horizons adjacent to five seagrass species in the intertidal and subtidal zone of a tropical seagrass bed (Gazi Bay, Kenya). Two benthic copepod communities could be identified mainly based on the tidal position of the samples: a first community was collected near the intertidal seagrasses Halophila ovalis and Halodule wrightii; a second community occurred near the subtidal seagrasses Thalassia hemprichii, Syringodium isoetifolium and Halophila stipulacea. The first community was mainly determined by sediment characteristics (e.g. skewness), while the second community was split off based on organic matter content (% TOM), nutrient and pigment values. A subtle combination of horizontal and vertical niche segregation was reported for the dominant copepod families. Species of the families Thalestridae, Laophontidae and Diosaccidae were structured by tidal position and showed a strong preference for the subtidal zone. The opposite strategy, i.e. a clear preference for the intertidal zone, was found for copepods belonging to the families Paramesochridae and Canuellidae. In addition, Apodopsyllus africanus (Paramesochridae) was well-adapted to stress and was concentrated in the deeper sediment layers near the subtidal seagrasses. On the other hand, Canuellidae, as filter feeders, were concentrated in the upper centimetres of the sediment. The families Ectinosomatidae and Cletodidae did not show any vertical or horizontal segregation. On the species level, however, clear horizontal niche segregation was detected for the family Cletodidae. In addition to the reported ecological results, the study material was used to evaluate different niche definitions. We found tidal position to be the most important factor forcing harpacticoids to specialise. Sediment depth horizon was less powerful in dividing the families into different guilds (from specialists to generalists) based on standardised niche breadth. The present study documents the subtle habitat partitioning of co-existing species in a limited area and its role in sustaining high biodiversity in the community.     

Speciation analysis of butyltin compounds in sediments of the Theoule harbour (France) by GC/AES

Over the last years, great progress in the research on speciation of butyltins has been made. Many coupling techniques have been successfully developed, with better applications to sediments samples in the environment. Sediments were collected from 1999 to 2000 to elucidate butyltin pollution in Theoule harbour. Most of the analysed samples showed evidence of butyltin compounds. The results show that the concentration of Tributyltin (TBT) was in the range 20–200?µg/kg in March 1999, 20–340?µg/kg in June 1999, 180–1280?µg/kg in July 2000, and 55–820?µg/kg in October 2000. A comparison of the MBT, DBT, and TBT results show that in 1999 the concentrations were in the order TBT?DBT?>?MBT, with some exceptions. The patterns observed in many sediment cores show a great disparity of organotin input concentration among the cores collected during one month and also during two different months, and from one season to the other. This paper provides information on the use of the acetic acid leaching system in the determination of butyltin. The method is applied to evaluate the occurrence of these species in sediments from the Theoule harbour, between 1999 and 2000. In this study, a GC/AES was applied, complemented with acetic acid leaching and monitored using two certified reference materials: PACS-2 reference sediment and BCR 462 (Report EUR 18406 EN, 1998).     

Der Einsatz von Pflanzentests bei der Sedimentbewertung

Up to now, sediment studies have mainly used standardized aquatic bioassays with organisms of the three trophic levels. Among these, algae are the only representatives of the entire plant kingdom. Bioassays with higher plants have hardly been used for the assessment of sediments. The aim of the present study is to demonstrate that the use of higher plants in biotests for analyses of anthropogenically contaminated sediments yields valuable results, which may be included in a concept for the integrated assessment of waters. The contamination by environmental chemicals was determined in the River Elbe by means of samples taken at the Fahlberg-List industrial site at Magdeburg in combination with studies in a reference area on the Müritz-Elde Waterway (Eldenburger Kanal). Sediment extracts and pore waters were tested with the aquatic lemna test. For comparison, first sediment contact tests withLemna minor were tried out. The whole extract of the sediment from Fahlberg-List Magdeburg and one fraction F5 caused distinct damages of the plants. Obviously, the phytotoxic substances of the whole extract are preferentially concentrated in the highly polar fraction F5. A comparison with chemical analytical data proved that the whole fraction F0 and the fraction F5 were heavily contaminated with chemicals. Assays with pore water from this sediment and with the whole sediment also caused a strong inhibition of growth. These results confirm the high contamination of the sediment from Magdeburg. The tests with the reference sediment suggested only a moderate toxic contamination. The results of this study prove that the selected aquatic plant,Lemna minor, is basically able to indicate contamination. In the aquatic test of the sediment extracts, it showed weak, but very selective, responses to certain classes of contaminants. Fractionating of the sample and subsequent chemical analysis combined with toxicity tests allow to narrow down the groups of substances causing toxic effects. This toxicity was confirmed by analyses of the pore waters and whole sediment samples. Together with other toxicity tests (e.g. standardized bioassays) and combined with biological benthos examinations, an overall judgment can be given for the integrated assessment of waters.     

“生物有效性测量”与“全沉积物毒性识别评估(TIE)”联用有效识别出沉积物中主要致毒污染物

沉积物中污染物种类繁多,准确判断其中产生生物毒性的主要来源是个难点,本文作者先采用TIE法初步判断出主要致毒污染物为有机物和重金属(毒性描述阶段(相I)),传统的毒性单位分析结果显示Cr、Cu、Ni、Pb和Zn主要致毒重金属,而为氯氰菊酯、氯氟氰菊酯、溴氰菊酯和氟虫腈为主要致毒有机物中(毒性鉴定阶段(相II))。采用4步分级提取法和Tenax提取法分析了重金属和有机物的生物有效性。生物有效性毒性单位分析更加准确地锁定了毒性主要贡献重金属为Zn、Ni和Pb,毒性主要贡献有机物为氯氰菊酯、氯氟氰菊酯和氟虫腈。沉积物的稀释降低了重金属的毒性并使其毒性贡献鉴定变得复杂,生物有效性测量可以有效地提高TIE结果的准确性。
精选自Xiaoyi Yi, Huizhen Li, Ping Ma and Jing You. Identifying the causes of sediment-associated toxicity in urban waterways in South China: Incorporating bioavailabillity-based measurements into whole-sediment toxicity identification evaluation. Environmental Toxicology and Chemistry: Volume 34, Issue 8, pages 1744–1750, August 2015. DOI: 10.1002/etc.2970
详情请见http://onlinelibrary.wiley.com/doi/10.1002/etc.2970/full     

“生物有效性测量”与“全沉积物毒性识别评估(TIE)”联用有效识别出沉积物中主要致毒污染物

沉积物中污染物种类繁多,准确判断其中产生生物毒性的主要来源是个难点,本文作者先采用TIE法初步判断出主要致毒污染物为有机物和重金属(毒性描述阶段(相I)),传统的毒性单位分析结果显示Cr、Cu、Ni、Pb和Zn主要致毒重金属,而为氯氰菊酯、氯氟氰菊酯、溴氰菊酯和氟虫腈为主要致毒有机物中(毒性鉴定阶段(相II))。采用4步分级提取法和Tenax提取法分析了重金属和有机物的生物有效性。生物有效性毒性单位分析更加准确地锁定了毒性主要贡献重金属为Zn、Ni和Pb,毒性主要贡献有机物为氯氰菊酯、氯氟氰菊酯和氟虫腈。沉积物的稀释降低了重金属的毒性并使其毒性贡献鉴定变得复杂,生物有效性测量可以有效地提高TIE结果的准确性。
精选自Xiaoyi Yi, Huizhen Li, Ping Ma and Jing You. Identifying the causes of sediment-associated toxicity in urban waterways in South China: Incorporating bioavailabillity-based measurements into whole-sediment toxicity identification evaluation. Environmental Toxicology and Chemistry: Volume 34, Issue 8, pages 1744–1750, August 2015. DOI: 10.1002/etc.2970
详情请见http://onlinelibrary.wiley.com/doi/10.1002/etc.2970/full     

“生物有效性测量”与“全沉积物毒性识别评估(TIE)”联用有效识别出沉积物中主要致毒污染物

沉积物中污染物种类繁多,准确判断其中产生生物毒性的主要来源是个难点,本文作者先采用TIE法初步判断出主要致毒污染物为有机物和重金属(毒性描述阶段(相I)),传统的毒性单位分析结果显示Cr、Cu、Ni、Pb和Zn主要致毒重金属,而为氯氰菊酯、氯氟氰菊酯、溴氰菊酯和氟虫腈为主要致毒有机物中(毒性鉴定阶段(相II))。采用4步分级提取法和Tenax提取法分析了重金属和有机物的生物有效性。生物有效性毒性单位分析更加准确地锁定了毒性主要贡献重金属为Zn、Ni和Pb,毒性主要贡献有机物为氯氰菊酯、氯氟氰菊酯和氟虫腈。沉积物的稀释降低了重金属的毒性并使其毒性贡献鉴定变得复杂,生物有效性测量可以有效地提高TIE结果的准确性。
精选自Xiaoyi Yi, Huizhen Li, Ping Ma and Jing You. Identifying the causes of sediment-associated toxicity in urban waterways in South China: Incorporating bioavailabillity-based measurements into whole-sediment toxicity identification evaluation. Environmental Toxicology and Chemistry: Volume 34, Issue 8, pages 1744–1750, August 2015. DOI: 10.1002/etc.2970
详情请见http://onlinelibrary.wiley.com/doi/10.1002/etc.2970/full     

Toxicological effects of mouse diet contaminated with tributyltin on the immune and neurological systems of C57BL/6 mice

Organotin compounds, widely used as antifouling agents, are known to bioaccumulate in the food chain. Among organotin compounds, tributyltin (TBT), a toxic and widespread contaminant, has become a serious factor in environmental pollution and is suspected of being immunotoxic in animals. The purpose of this study was to assess the effects of 80 µg of TBT per kilogram of body weight (kg bw), provided in food, on the immune and neurological systems of C57Bl/6 mice. Data showed that TBT increased the proliferation of T and B lymphocytes in both adult and juvenile female and juvenile male mice, but that it decreased the proliferation of both T and B lymphocytes in adult male mice. The macrophages activity in female and male juvenile mice was higher than in adults of both sexes. The natural killer cytotoxic activity was also increased in juvenile and adult males and females compared to the control groups. In the brain, we observed the presence of TBT in the hippocampus, the striatum, the cortex, and the cerebellum in both the male and female groups. The highest levels were observed in the cortex of females and males, while the lowest levels were found in the cerebellum. TBT also induced an increase in the levels of the antioxidant glutathione (GSH) in the striatum, the hippocampus and in cortical structures but not in the cerebellum where the levels of TBT are lower. Our findings indicate that TBT modulated the immune and nervous systems causing endocrine and nervous perturbations.