Noninvasive biomarkers of compromised health from contaminant exposure in wildlife

该提案解决了关于暴露于环境污染物与暴露于这些污染物的动物的压力生物指标之间关系的知识方面的一个重要空白。我们的研究结果将支持合理的科学建议的基础，可以被公众理解，并可以告知监管政策。 环境污染与人类、家畜和野生动物的一系列慢性疾病有关。我将利用自然暴露的本地野生动物，在实验动物实验室研究的支持下，研究暴露于污染物的毒理学影响。 作为研究人员和生态毒理学家，我们在努力改善野生动物的福祉时，经常对它们产生负面影响，具有讽刺意味的是，我们使用致命的采样来研究污染物暴露的影响，大大增加了对野生物种进行侵入性研究的不可接受性。最近，毒理学家们认识到，通过研究活体动物，我们可以学到更多的东西，而不是通过测量它们组织中的污染物残留。我的研究项目主要集中在开发和验证野生动物关键物种的生化反应，以检测早期污染物相关的身体功能变化。 这些对污染物的反应，称为生物标志物，包括免疫和激素反应，氧化应激的措施，以及再次保护这些破坏性自由基或氧化应激的抗氧化剂储存。慢性压力也会损害健康，并通过微妙的长期成本降低受影响动物的抗病能力。脊椎动物的压力是通过产生糖皮质激素（类固醇）激素如皮质醇来表达的，并已在鸟类，鱼类和哺乳动物中进行了测量。生物样本反映了这些激素水平在几分钟（血液和唾液），几小时（尿液和粪便）或几周到几个月（头发，羽毛）的综合。 在这个建议中，我检查了野生鸟类和哺乳动物的一套生物标志物，尽可能使用微创技术，以检测污染场地对野生动物健康的影响。大多数生态毒理学家的假设是，污染物暴露造成慢性应激。然而，没有研究检查污染物，慢性应激和污染物暴露的生物标志物之间的关系。 我将研究陆地生态毒理学的两个主要空白：1）我们是否以及如何使用来自毛发或羽毛的糖皮质激素（应激）激素作为测量暴露于污染物的动物慢性应激的非侵入性手段。2)它们是脊椎动物物种中最一致、可靠、灵敏和优选非致死性的毒性生物标志物。这项工作最终将提出建议，说明上述生物标志物反应的哪种组合，包括慢性压力，最能预测污染驱动的野生动物风险。

This proposal addresses a vital gap in knowledge about the relationship between exposure to environmental contaminants and biological indicators of stress in animals exposed to these pollutants. Our findings will support the foundation for rational scientific recommendations that can be understood by the general public, and which can inform regulatory policy. Environmental pollution is associated with a range of chronic diseases in humans, domestic animals, and wildlife. Using naturally exposed, native wildlife, supported by laboratory studies on experimental animals, I will study toxicological impacts of exposure to contaminants. We, as researchers and ecotoxicologists have often had negative effects on wildlife in our effort to improve their well being, ironically using lethal sampling to study impacts from contaminant exposure, adding substantially to the unacceptability of invasive research on wild species. Recently, toxicologists have recognized that we can learn much more by studying live animals, than we can by measuring pollutant residues in their tissues. My research program has focused on developing and validating biochemical responses in key species of wildlife to detect early contaminant related changes in body functions. These responses to contaminants, referred to as biomarkers, include immunological and hormonal responses, measures of oxidative stress, and antioxidant stores which protect again these damaging free radicals, or oxidative stress. Chronic stress will also compromise health and decrease disease resistance in affected animals through subtle, long-term costs. Stress in vertebrates is expressed through production of glucocorticoid (steroid) hormones such as cortisol, and has been measured in birds, fish, and mammals. Biological samples reflect these hormones levels integrated over minutes (blood and saliva), hours (urine & feces), or weeks to months (hair, feathers). In this proposal, I examine a suite of biomarkers in wild birds and mammals, as much as possible using minimally invasive techniques, to detect health effects in wildlife from contaminated sites. The assumption of most ecotoxicologists is that contaminant exposure imposes chronic stress. However, no studies have examined the relationship between contaminants, chronic stress, and biomarkers of pollutant exposure. I will investigate two major gaps in terrestrial ecotoxicology; 1) if and how we can use glucocorticoid (stress) hormones from hair or feathers as a non-invasive means of measuring chronic stress in animals exposed to contaminants. 2) which are the most consistent, reliable, sensitive, and preferably non-lethal biomarkers of toxicity across vertebrate species. This work will ultimately produce recommendations regarding which combination of the above biomarker responses, including chronic stress, are most predictive of pollution-driven risks to wildlife.