Noninvasive biomarkers of compromised health from contaminant exposure in wildlife

这项建议解决了关于暴露于环境污染物和暴露于这些污染物的动物的生物应激指标之间关系的知识的一个重要空白。我们的发现将支持合理的科学建议的基础，这些建议可以被普通公众理解，并可以为监管政策提供信息。 环境污染与人类、家畜和野生动物中的一系列慢性病有关。使用自然暴露的本地野生动物，并辅之以对实验动物的实验室研究，我将研究接触污染物的毒理学影响。 我们，作为研究人员和生态毒理学家，在努力改善野生动物的福祉的过程中，经常对野生动物产生负面影响，具有讽刺意味的是，我们使用致命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程度。最近，毒物学家已经认识到，我们通过研究活动物可以学到比通过测量它们组织中的污染物残留更多的东西。我的研究计划专注于开发和验证关键野生动物物种的生化反应，以检测与污染物相关的身体功能早期变化。 这些对污染物的反应被称为生物标记物，包括免疫和激素反应，氧化应激的测量，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。慢性应激还将损害健康，并通过微妙的长期代价降低受影响动物的抗病能力。脊椎动物的应激是通过产生糖皮质激素(类固醇)，如皮质醇来表达的，在鸟类、鱼类和哺乳动物中也有测量。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(头发和羽毛)的综合水平。 在这项建议中，我尽可能地使用微创技术检查野生鸟类和哺乳动物的一套生物标志物，以检测受污染地点的野生动物对健康的影响。大多数生态毒理学家的假设是，接触污染物会造成慢性压力。然而，还没有研究检查污染物、慢性压力和污染物暴露的生物标记物之间的关系。 我将调查陆地生态毒理学中的两个主要空白：1)我们是否以及如何使用毛发或羽毛中的糖皮质激素作为一种非侵入性手段来测量暴露在污染物中的动物的慢性应激。2)在脊椎动物物种中，哪些是最一致、最可靠、最敏感、最好是非致命性的毒性生物标志物。这项工作最终将提出建议，说明上述生物标记物反应的哪种组合，包括慢性应激，最能预测由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.