基于多生物标志物污染指数法的北部湾潮间带污染程度评价

采用多生物标志物污染指数法（multi-biomarker pollution index,MPI）评价北部湾潮间带的污染状况.2011年4月在北部湾沿海潮间带设置9个站位采集波纹巴非蛤（Paphia undulata）和沉积物样品,分析波纹巴非蛤鳃和内脏中9种生物标志物活性（含量）以及沉积物中12种化学污染物的含量.根据每种生物标志物与沉积物中化学污染物之间的皮尔逊相关性,筛选波纹巴非蛤鳃中的氧化型谷胱甘肽（GSSG）、还原型谷胱甘肽（GSH）和谷胱甘肽硫转移酶（GST）,以及内脏中的硫代巴比妥酸反应物（TBARS）和谷胱甘肽过氧化物酶（GPx）作为评价指标,将某站位上述5种生物标志物响应值赋予相应的污染指数,叠加后即得到该站位的MPI值.结果表明,不同站位污染水平有所差别,所有站位的MPI值范围在18～39之间,涵盖＂清洁＂、＂质量良好＂、＂轻微污染＂三个等级,未出现＂污染＂或＂严重污染＂站位.湛江市北港码头（S1）、钦州湾老人沙浅滩（S3）、防城港西湾（S4）和北海市西场（S7）呈轻微污染,其他站位环境清洁或质量良好,说明北部湾潮间带整体环境质量良好,但已开始受到人为活动的轻微干扰.     

Variation of antioxidant biomarkers in the edible oyster Saccostrea cucullata collected from three different water bodies of Sundarbans

Variations of antioxidant biomarkers such as catalase (CAT), superoxide dismutase (SOD) activities and lipid peroxidation (LPO) were studied in edible part of mangrove oyster Saccostrea cucullata, collected from three different water bodies, such as Namkhana (S-I), Frazergaunge (S-II) and Sajnekhali (S-III) of Indian Sundarbans which are exposed to different degrees of anthropogenic activity. The study was conducted for consecutive two years (2010 and 2011) in the respective water bodies. Characteristics of biomarkers in oyster from the two polluted water bodies, i.e. S-I and S-II, are similar in nature in comparison to less polluted site (S-III). The catalase, superoxide dismutase activity and lipid peroxidation in oyster flesh exhibit significant (p<0.01) spatial and temporal variation among the three stations. Oysters from S-I were significantly higher (p<0.05) in antioxidant enzyme activities than oysters from S-III, which differ in their amount of pollution sources. Maximum antioxidant enzymes activity of all collected samples were recorded in pre-monsoon time and decreased in monsoon season. But maximum lipid peroxidation was noted during monsoon followed by post-monsoon and pre-monsoon.     

Effects to perfluorooctane sulfonate (PFOS) on the mollusk Unio ravoisieri under laboratory exposure

To understand acute toxicity and oxidative stress of perfluorinated compounds in the freshwater ecosystems, we exposed freshwater mussels (Unio ravoisieri) to perfluorooctane sulfonate (PFOS), over a range of concentrations from 10 to 100?mg/L, in a laboratory experiment. Lethal concentration (LC50) was of about 65.9?mg/L after 96?h of exposure. The oxidative stress was assessed in gill and digestive gland of the freshwater mussels after 7 days of exposure to different nominal PFOS concentrations (C1=?2?mg/L, C2?=?6?mg/L and C3=?10?mg/L). C1 and C2 increased significantly (p?<?.05) the superoxide dismutase activity in both tissues compared, while the highest C3 decreased the enzyme activity. This implements an unfavourable response that highlights the excess of reactive oxygen species produced after contamination. The Catalase activity was also increased by about 40.05% and 66.63%, respectively, in gill and digestive gland after exposure to C3. The Malondialdehyde (MDA) level was increased in both gill and digestive gland in a concentration-dependent pattern. In contrast, the contamination of U. ravoisieri by PFOS did not affect the acetylcholinesterase activity in both organs (p?>?.005). These results provided information on potential biomarkers that could be effectively applied for the monitoring of freshwater ecosystem using indicator species such as U. ravoisieri.     

Exposure of Marine Mammals to Genotoxic Environmental Contaminants: Application of the 32P-Postlabeling Assay for Measuring DNA-Xenobiotic Adducts♯

There is little information on exposure of marine mammals to genotoxic environmental contaminants. The 32P-postlabeling assay has been successfully used to assess exposure to genotoxic polycyclic aromatic compounds in fish and humans. In the present study, a preliminary investigation showed that polycyclic aromatic compound-like DNA adducts were present in hepatic tissues of harbor seals (Phoca vitulina richardsi) exposed to petroleum following the Exxon Valdez oil spill. However, for marine mammals, effects from changes in tissue condition on DNA recovery and quality is of concern, because tissue samples are often collected from animals that have been dead for unknown periods of time. To assess the effects of postmortem thermal history on DNA recovery from tissue and on DNA adduct quantitation, samples of harbor porpoise (Phocoena phocoena) hepatic tissue were incubated for up to 10 d at 4 and 30 °C. Only traces (<4 g) of hepatic DNA were recovered from 200 mg of tissue after incubation at 30 °C for 36 h. At 4 °C, DNA (50–130 g) was recovered from tissue incubated for up to 6 d; whereas DNA recovery at 10 d was minimal. Chromatograms of 32P-labeled DNA digests of liver tissue held at 4 and 30 °C and salmon sperm DNA held at 30 °C for 2 d had comparable profiles, suggesting that alteration of DNA bases had occurred during incubation of porpoise liver tissue. Moreover, the chromatograms of DNA extracted from liver tissues of harbor porpoises caught incidentally in a northwest Atlantic fishery, packed in ice and sampled several days later also exhibited similar altered DNA structures. Although, altered DNA structures that can interfere with the DNA adduct quantitation were present in autolyzed tissue, changes in the 32P-postlabeling chromatography conditions can decrease the interference. Moreover, in a study with tissues taken from California sea lions (Zalophus californianus) immediately postmortem and stored at –80 °C until processing, DNA structures associated with tissue breakdown were not observed. The DNA from sea lions, however, had putative age-dependent hepatic DNA modifications, which have a distinctive profile, and must be considered when evaluating exposure of marine mammals to polycyclic aromatic compounds. Overall, the findings showed that with attention to the postmortem thermal history of the tissue samples hepatic DNA adducts, as measured by 32P-postlabeling, have the potential to serve as a biological indicator of exposure of marine mammals to environmental genotoxic compounds.     

MODELKEY. Models for assessing and forecasting the impact of environmental key pollutants on freshwater and marine ecosystems and biodiversity (5 pp)

BACKGROUND: Triggered by the requirement of Water Framework Directive for a good ecological status for European river systems till 2015 and by still existing lacks in tools for cause identification of insufficient ecological status MODELKEY (http:// www.modelkey.org), an Integrated Project with 26 partners from 14 European countries, was started in 2005. MODELKEY is the acronym for 'Models for assessing and forecasting the impact of environmental key pollutants on freshwater and marine ecosystems and biodiversity'. The project is funded by the European Commission within the Sixth Framework Programme. OBJECTIVES: MODELKEY comprises a multidisciplinary approach aiming at developing interlinked tools for an enhanced understanding of cause-effect-relationships between insufficient ecological status and environmental pollution as causative factor and for the assessment and forecasting of the risks of key pollutants on fresh water and marine ecosystems at a river basin and adjacent marine environment scale. New modelling tools for risk assessment including generic exposure assessment models, mechanistic models of toxic effects in simplified food chains, integrated diagnostic effect models based on community patterns, predictive component effect models applying artificial neural networks and GIS-based analysis of integrated risk indexes will be developed and linked to a user-friendly decision support system for the prioritisation of risks, contamination sources and contaminated sites. APPROACH: Modelling will be closely interlinked with extensive laboratory and field investigations. Early warning strategies on the basis of sub-lethal effects in vitro and in vivo are provided and combined with fractionation and analytical tools for effect-directed analysis of key toxicants. Integrated assessment of exposure and effects on biofilms, invertebrate and fish communities linking chemical analysis in water, sediment and biota with in vitro, in vivo and community level effect analysis is designed to provide data and conceptual understanding for risk arising from key toxicants in aquatic ecosystems and will be used for verification of various modelling approaches. CONCLUSION AND PERSPECTIVE: The developed tools will be verified in case studies representing European key areas including Mediterranean, Western and Central European river basins. An end-user-directed decision support system will be provided for cost-effective tool selection and appropriate risk and site prioritisation.     

华北地区下古生界海相烃源岩饱和烃生物标志物地球化学特征

本文对华北地区下古生界海相烃源岩生物标志化合物地球化学进行了系统的研究工作，并在烃源岩抽提物中检测到种类丰富的生物标志物，在此基础上讨论了生物标志化合物的分布特征及其地球化学意义，这一工作不仅为华北地区下古生界油气勘探提供了理论依据，而且丰富了碳酸盐岩有机地球化学理论。     

特种生物标志物作为溢油指示物（或指标）的研究

用毛细管GC－MS对不同水环境中不同油类的特种生物标志物进行检测，结果表明，异戊二烯烷烃类姥鲛烷与植烷的比值在两个多月的风化过程中不受风化的影响；萜烷和甾烷的某些比值参数在一年的风化过程中（或室内自然放置4年）不受风化的影响。姥鲛烷与植烷的比值可以作为风化两个多月的溢油指示物（或指标）；萜烷和甾烷比值可以作为风化一年（或室内自然放置4年）的溢油指示物（或指标）。     

山东半岛南部近海表层沉积物中脂类生物标志物的组成及形态分析

分析了山东半岛南部近海表层沉积物中游离态和碱不稳定结合态脂类物质的组成,结果显示:脂肪酸呈现以16∶0为主峰的单峰形分布趋势,具明显偶碳优势,海源为其主要来源,脂肪酸主要以结合态形式存在,不同类别的脂肪酸形态分布略有差异,脂肪酸的结构和来源是影响脂肪酸形态分布的重要因素;同样以海源为主的甾醇则主要以游离态形式存在,但陆源甾醇的结合态比重相对较高;烷烃呈现以C29烷烃为主峰的单峰形分布趋势,陆源输入是其主要来源;烷烃主要以游离态形式存在,且UCM(不可分辨成分)峰仅出现在游离态烷烃的气相色谱图中。     

油田污染土壤残油组成与特征参数分析

为揭示石油在土壤中的降解规律、残油组分特征,筛选土壤残油的生物降解性评价参数,选取大庆、胜利、百色3个油田区共18个深度降解的石油污染土样,利用气相色谱-质谱联用仪(GC-MS)分析了土壤残油中链烷烃(正烷烃+姥鲛烷+植烷)、多环芳烃(PAHs)、萜烷、甾烷及三芳甾烃等5类超过100种石油烃单体.结果表明,经长期降解后残留在土壤残油中总烷烃残留率低于10%,总PAHs残留率低于30%,而萜烷、甾烷及三芳甾烃等生物标志物较难降解.正烷烃降解性随碳数增加有下降的趋势,但碳数<37的正烷烃降解率平均值>80%;PAHs中2～4环PAHs降解率平均值>70%,5～6环PAHs较难生物降解;萘系列、菲系列、系列及苯并[e]芘系列中随烷基取代数增多而残留率增高.残油中可被GC-MS识别的组分<3%,主要为碳数高于20的正烷烃、烷基取代萘和菲、萜烷、甾烷及三芳甾烃等生物标志物.基于烷烃及多环芳烃组成特征,筛选出6个由易降解组分含量与总油或难降解组分含量的比值构成的标准残油的特征参数,可用于判断污染土壤中石油污染物的生物降解性.     

Effects of subchronic exposure to carbofuran on antioxidant defence system and malondialdehyde levels in common carp (Cyprinus carpio L.)

The present study focused on the assessment of oxidative stress induction by pesticides such as carbamates which are widely used as insecticides and nematicides and contaminate aquatic ecosystems on certain biomarkers in liver of common carp (Cyprinus carpio L.). Biomarkers selected for stress monitoring were malondialdehyde (MDA), an index of lipid peroxidation, and antioxidant defence system enzymes, mainly catalase (CAT), glutathione reductase (GR), and glutathione-S-transferase (GST) activities in liver of fish exposed to 0, 10, 50, or 100?µg?L^?1 of carbofuran for 4, 15, or 30 days. Oxidative stress was found in liver of common carp exposed to carbofuran which was manifested by a decrease in CAT and GR activities after 4 and 30 days of exposure. An adaptive response was probably produced since at day 15 no modifications in the CAT activity and increased GR activity were observed. In addition, a decrease in MDA content with the highest concentration of carbofuran used was found after 30 days of exposure. However, no significant changes were found in GST activity showing a varied response. The results concerning oxidative and antioxidant profiles indicate that subchronic exposure to the insecticide carbofuran is capable of inducing oxidative stress in fish.