基于细胞报告菌株的环境铅生物可给性与风险评价研究

The unprecedented challenge facing human and ecosystem health as a result of pollution requires streamlined approaches to risk assessment, which is a prerequisite for risk management. This proposal uses new state-of-the-art approaches to different components of risk assessment and combines these in a new, unique, full-spectrum approach that is designed to capture efficiency and be more cost effective. The pollutant on which we focus as a test case for our approach is lead (Pb), which is now considered to be the most important pollutant globally, as well as the subject of serious pollution issues in China. Additionally, Pb has specific biological effects, with children described as having “exquisite sensitivity” to the neurotoxicological effects of Pb, including impaired cognitive development..A central concept we adopt involves bioavailability-based risk assessment, which is in part facilitated by cell-based methods in what has been referred to as “Toxicology for the 21st century”. Cell-based methods offer scope to measure simple bioavailability of pollutants on one hand and on the other hand to measure specific biological effects. We propose to use whole-cell bioreporters, i.e. bacteria that give an optical response signal or “report” on pollutants, to measure the bioavailability of Pb and to test for developmental neurotoxicity using a biomedical assay based on a commercially available human cell line..We further propose to integrate the results of cell-based testing into an existing and modelling framework for predictive toxicity that has been validated and accepted for use in risk assessment in the US and the EU. The modelling approach chosen is suitable for understanding chemical speciation, and therefore the environmental biogeochemical controls that mediation the toxicity of Pb, as well as being validated to predict toxicity itself. Because work on real field samples will commence early in the study, to help guide our understanding of how to calibrate models to cell-based methods, Pb toxicity to a model-validated test organism (C. dubia) will be measured alongside cell assays performed on field samples..This study will also use spatial analysis, which has potential for more effective understanding of causative factors underlying risk, for instance, sources of environmental pollutants and how transformations that affect toxicity occur over space and time. Our test system will be Taihu, and, because of the potential for and importance of remobilisation of pollutants such as Pb, a final aspect of our work incorporates field trials on water-sediment interactions at the Taihu Laboratory for Lake Ecosystem Research (TLLER); this provides a superlative level of facilities and personnel support to ensure the success of the crucial aspect of field work for this very ambitious project.

史无前例的环境污染挑战需要更加快捷和可靠的风险评估流程。我们期望采用创新型的评估方法，改进风险评估流程中的关键部分，进而提高效率和降低成本。太湖流域面积大，周边经济发展快速。在生物地球化学方面具有优秀的地域差异性，并在局部地区面临严重的铅污染。因此将作为本课题的主要研究区域。本项目将以重金属铅为主要研究对象，使用全细胞报告菌株来测量铅的生物可给性，并利用人类细胞株检验铅对神经系统的毒害程度。所得到的结果整合到美国和欧盟广泛认可的用于预测毒性的生物地球化学模型中，并与传统毒性测试方法（利用模糊网纹蚤）来进行对比。考虑沉积物中铅再活化释放的可能性，进一步的研究采用野外试验的方法，考察水-沉积物相互作用。本项目的研究结果将更好的为环境影响评价和环境管理提供新的理论依据和方法。

前所未有的环境污染需要更快速和更可靠的风险评估。该项目的目标是开发创新的方法，作为改进环境风险评估的关键部分，从而提高效率和降低成本。示范区为太湖流域，代表着一个经济快速发展的大区域，铅是一种严重的全球性污染物，作为一个试验案例，是主要关注的焦点。采用全细胞生物传感器测量铅的生物利用度，并将结果集成到生物地球化学模型中，该模型作为风险评估工具被美国和欧盟广泛认可。此外，还进行了利用湖泊沉积物的研究。在该项目期间，工作从最初的计划扩大到包括对某些金属的研究，这些金属可以作为微量营养素，同样也可以作为毒物，因此也与淡水中有害藻华的形成有关。.此项目成果通过了环境风险评估工作的标准方法验证，证明了这是一种成功和快速的风险评估方法。这一结果与最初的项目目的和目标可能产生的最佳结果完全一致。本项目中所证明的风险评估方法不存在任何障碍，可以更普遍地采用和使用。关于微量营养素的环境风险评估工作表明，采用非常小的微量元素干预措施，使危害较小的藻类能够战胜剧毒的有害藻类，这是一种安全和有意义的方法，并为更大规模的实地试验指明了前进的方向。本项目开发的流式细胞仪数据驱动分析和铜络合载体高通量筛选的两个方法代表了快速解决环境数据需求的全新方法，并且是完整的；任何研究人员或环境工作者都可以使用这些方法。就学术价值而言，迄今为止已发表了四篇期刊论文（其中两篇在本学科领域影响因子最高的期刊上，根据期刊引用报告分区，为一区），另外两篇论文正在审稿中，另外四篇论文目前正在编写中。