基于原位生物测试的水生态风险评估技术研究

我国流域水环境呈现典型的复合污染特征，亟需发展基于生物效应的生态风险评估方法，以实现环境管理和生态修复的精准化.在野外原位暴露下受试生物受到多种污染物的共同胁迫，可以准确表征研究位点复合污染所产生的生态风险.原位生物测试较传统实验室生物测试具有更高的环境真实性和生态相关性，较野外生物监测对生物体承受的外源污染压力更清晰、可控.综述了基于原位生物测试的水生态风险评估技术，旨在促进该技术在我国水环境监测中的应用，提高生态风险评估的准确度.总结了国内外近年来原位生物测试的研究特色，详细阐述了实施过程中受试生物选择、暴露装置设计和研究位点选择的原则，以及原位生物测试方法在水环境生态风险评估中的应用案例.结果表明:①对原位生物测试实施要素进行规范化形成标准，将有利于该方法在环境管理中的推广应用.②利用原位生物效应、原位生物体内浓度以及二者与环境浓度相结合进行风险评估，是原位生物测试在生态风险评估中的三类应用类型.③原位生物暴露与被动采样的联合应用可同步获取原位生物效应和污染物生物可利用浓度，有利于实现全面准确的风险评估，应用潜力较大.研究表明，选用本土模式生物，采用多层次的毒性终点，设计简单有效的暴露装置，并同时考虑原位生物效应和环境浓度将有利于原位生物测试方法在我国的发展. 

In Situ Bioassay-Based Aquatic Ecological Risk Assessment

Water pollution in China is characterized as combined pollution with multiple stressors, calling for developments of ecological risk assessment approaches based on biological effects to improve accuracy in environmental management and remediation. Test animals expose to multiple stressors in the field and characterizing their effects is regarded as a good indicator for the site-specific ecological risk of combined pollution. In situ bioassays present high environmental realism and ecological relevance compared to traditional laboratory bioassays, and also provide better control over stressor exposure to test animals than field-based monitoring approaches. In this paper, in situ bioassay-based aquatic ecological risk assessment methods are reviewed to promote the application of in situ bioassays in national aquatic environmental monitoring and to achieve accurate ecological risk assessment. By summarizing the features of in situ bioassay research at home and abroad in recent years, the principles of choosing test animals, designing exposure devices, and selecting study sites in the implementation process are discussed in details, and the application cases of in situ bioassays in aquatic ecological risk assessment are illustrated. The results show that: (1) Standardizing the implementation of in situ bioassays is beneficial to promoting the applications of this method in environmental management. (2) The application cases are categorized into three classes, including in situ-based effects, in situ-based body residues, and joint usage of environmental concentrations. (3) It is of great interest to achieve a comprehensive and accurate risk assessment by combining in situ bioassays and passive sampling techniques, which could simultaneously provide in situ effects and bioavailable concentrations of contaminants. The research shows that it would benefit the development of in situ bioassay methods in China by choosing native model organisms, determining multi-biomarkers, designing easy and effective exposure devices, as well as integrating in situ-based effects and environmental concentrations for risk assessment.