Modifying factors of toxicant impacts on biota

毒物对生物群影响的改变因素

• 批准号: 8155-2007
• 负责人: Dixon, George
• 金额: $ 2.45万
• 依托单位: University of Waterloo
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2011
• 资助国家: 加拿大
• 起止时间: 2011-01-01 至 2012-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=474339
• 关键词: Modifying; factors; toxicant; impacts; biota

The long-term objectives of my laboratory's program in environmental toxicology are: 1) to understand the environmental factors that modify the impacts of toxic chemicals on biota and, 2) to develop methods to assess contaminant impacts on free-living organisms. An understanding of modifying factors is crucial for the application of laboratory toxicology data to the field, or the application of field data collected at one site to another, during site-specific quantitative environmental risk assessment (QERA) of contaminants to protect the environment. While looking at the effects of various modifying factors over my career, it has become evident that what we are really looking at is how environmental factors modify the bioavailability of a chemical; how exposure concentration, time and assimilation/depuration kinetics interact to achieve a critical (threshold of toxicity) chemical concentration in the organism. Models developed using this approach provide a deterministic link between hypothesis formulation and testing in environmental toxicology. We have used this approach to characterize the kinetics of mercury in Lake Victoria, the toxicity of Cd in sediment to benthic invertebrates in both the laboratory and the field, the toxicity of tributyl tin oxide to aquatic invertebrates in freshwater, and the toxicity of metals in sediments from metal-impacted lakes. In the future we will examine dietary vs. waterborne toxicity of metals to invertebrates, the ability to predict acute and chronic toxicity of copper to aquatic invertebrates, the toxicity of nanoparticles to aquatic biota and the interactive toxicity of ultraviolet light, products of combustion and metals to fish. Overall, the work contributes to our basic understanding of the impact of environmental contaminants, and to sound scientifically-based Canadian environmental regulations.

我实验室环境毒理学项目的长期目标是：1）了解改变有毒化学品对生物群影响的环境因素，2）开发评估污染物对自由生物体影响的方法。 在对污染物进行特定地点定量环境风险评估 (QERA) 以保护环境的过程中，了解修改因素对于将实验室毒理学数据应用于现场，或将在一个地点收集的现场数据应用于另一个地点至关重要。 在研究我的职业生涯中各种改变因素的影响时，很明显我们真正关注的是环境因素如何改变化学品的生物利用度；暴露浓度、时间和同化/净化动力学如何相互作用以在生物体中达到临界（毒性阈值）化学浓度。 使用这种方法开发的模型提供了环境毒理学假设制定和测试之间的确定性联系。 我们使用这种方法来表征维多利亚湖中汞的动力学、实验室和现场沉积物中镉对底栖无脊椎动物的毒性、三丁基氧化锡对淡水中水生无脊椎动物的毒性以及受金属影响的湖泊沉积物中金属的毒性。 将来，我们将研究金属对无脊椎动物的饮食毒性和水源毒性、预测铜对水生无脊椎动物的急性和慢性毒性的能力、纳米颗粒对水生生物群的毒性以及紫外线、燃烧产物和金属对鱼类的交互毒性。 总体而言，这项工作有助于我们对环境污染物影响的基本了解，并有助于完善以科学为基础的加拿大环境法规。