Isolating causative agents in complex mixtures

分离复杂混合物中的病原体

• 批准号: 312050-2011
• 负责人: Servos, Mark
• 金额: $ 1.89万
• 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=481112
• 关键词: Isolating; causative; agents; complex; mixtures

Subtle effects on the development and reproduction of fish have been reported globally associated with a variety of emerging contaminants of concern (e.g. pharmaceuticals). In recent years, the incidence of intersex, (e.g. eggs in male reproductive tissue) in fish has been reported widely in watersheds affected by municipal, industrial (e.g. pulp mill) and agricultural activities. In the Grand River in southern Ontario, very high levels of intersex (primary oocytes in testes) as well as changes in fish population (reduced gonad size) and community responses (relative species abundance) have been associated with municipal wastewater outfalls. Although a number of contaminants have been documented in wastewater effluents that alter endocrine function in fish through binding to the estrogen receptor, they cannot fully explain the observations in the receiving environment. Recent studies have suggested that a number of other chemicals and mechanisms may also contribute to the expression of intersex and altered reproductive performance in fish. These include compounds that block the androgen receptor (e.g. several pesticides, industrial contaminants) and habitat conditions such as reduced oxygen (hypoxia) that alter the normal synthesis and metabolism of natural hormones that are critical in development and reproduction. The chemicals or conditions responsible for these changes are usually associated with very complex mixtures making risk assessment and management very uncertain. The current proposal will explore this issue by developing techniques to isolate and identify potential causative contaminants in both municipal effluents and agricultural runoff in the Grand River watershed. The mechanisms controlling fate and bioavailability of these chemicals, as well as their ability to interact to alter critical biological functions controlling performance, will be modelled. The relationship of these identified chemicals in wild fish to the expression of whole organism and population level effects, especially intersex, will be examined in response to investments in treatment infrastructure in the watershed.

据全球报告，鱼类的发育和繁殖受到的微妙影响与各种新出现的令人关切的污染物（如药物）有关。 近年来，在受市政、工业（如纸浆厂）和农业活动影响的流域，广泛报告了鱼类中间性（如雄性生殖组织中的卵）的发生率。在安大略南部的格兰德河，非常高水平的雌雄同体（睾丸中的初级卵母细胞），以及鱼类种群的变化（性腺大小减少）和社区的反应（相对物种丰度）已与城市污水排放。 虽然在废水排放物中有一些污染物通过与雌激素受体结合而改变鱼类的内分泌功能，但它们不能完全解释接收环境中的观察结果。最近的研究表明，一些其他化学品和机制也可能有助于鱼类的两性表达和改变生殖能力。这些包括阻断雄激素受体的化合物（例如几种杀虫剂，工业污染物）和栖息地条件，如氧气减少（缺氧），改变了对发育和生殖至关重要的天然激素的正常合成和代谢。造成这些变化的化学品或条件通常与非常复杂的混合物有关，使得风险评估和管理非常不确定。目前的提案将探讨这一问题，开发技术，以隔离和识别潜在的致病污染物在城市污水和农业径流在格兰德河流域。 将模拟控制这些化学品的命运和生物利用度的机制，以及它们相互作用以改变控制性能的关键生物功能的能力。这些确定的化学物质在野生鱼类的表达的整个生物体和人口水平的影响，特别是雌雄同体的关系，将被检查在应对在流域处理基础设施的投资。