Collaborative Research: Fate and bioavailability of steroidogenic compounds in aquatic sediment

提案标题：合作研究：水生沉积物中类固醇化合物的命运和生物利用度主要研究者：Bartelt-Hunt， Shannon；院校：内布拉斯加大学林肯分校；内布拉斯加大学奥马哈分校提案号：CBET-0966850；环境暴露于高水平的类固醇与鱼类的负面生殖结果和潜在的人类健康影响有关，包括骨骼形成缺陷和对大脑发育的影响。先前发表的研究表明，外源类固醇会被水生沉积物吸收，但与沉积物相关的类固醇激素对水生生物的生物利用度尚不清楚。π吗?初步数据表明，与沉积物相关的类固醇仍然是生物可利用的，而且可能是水生系统中生物可利用的类固醇化合物的主要来源。这项提议的工作是创新的，因为它代表了第一个研究与沉积物如何改变类固醇对水生生物群的生物利用度的研究。pi将检查导致沉积物中雌激素和雄激素命运和转化的物理和化学因素，以及大型生物体暴露于生物活性类固醇激素的途径。拟议研究的结果将更好地了解沉积物在类固醇转化和生物吸收中的作用，并将支持在受类固醇化合物影响的水生系统中设计有效的缓解战略。本应用程序的目的是研究沉积物在环境命运中所起的作用，类固醇化合物的转化和生物利用度。本研究的中心假设是与沉积物相关的类固醇仍然具有生物可利用性。他们计划通过以下三个具体目标来测试他们的中心假设并实现该应用程序的目标：(1)确定类固醇对无所不在的淡水鱼——天头鲦鱼（fahead minow）具有生物可利用性的暴露途径，(2)评估控制沉积物中类固醇的物理化学机制，以及(3)通过在已知的类固醇性排放的水生系统中进行的对照实地研究来验证他们的实验室结果。该项目的教育和推广计划侧重于本科生和研究生教育，并向对内分泌干扰化合物感兴趣的区域、国家和国际团体提供信息。拟议的项目代表了一所研究型大学（内布拉斯加大学林肯分校）和一所主要的本科机构（内布拉斯加大学奥马哈分校）的教员之间的合作研究努力。概述这项研究的方法和结果的教育模块将整合到现有的课程中，重点是污染物的命运和运输，环境采样方法，以及由内布拉斯加大学林肯分校和内布拉斯加大学奥马哈分校的项目调查员教授的毒理学。关于环境中激素的研究结果和资料将通过内布拉斯加州大学季刊上发表的文章和为外行设计的互动网站向污水处理厂的经营者、公众传播。国际外联将通过与Corporación para Investigaciones Biológicas和哥伦比亚麦德林的安蒂奥基亚大学（University of Antioquia）的研究生交流计划实现。

Proposal Title: Collaborative Research: Fate and bioavailability of steroidogenic compounds in aquatic sedimentPrincipal Investigators: Bartelt-Hunt, Shannon; Kolok, AlanInstitutions: University of Nebraska-Lincoln; University of Nebraska-OmahaProposal Nos: CBET-0966850; CBET-0966858 Environmental exposures to elevated levels of steroids have been linked with negative reproductive outcomes in fish and potential human health impacts including defective bone formation and impacts on brain development. Previously-published studies indicate that exogenous steroids will sorb to aquatic sediments, however the bioavailability of sediment-associated steroid hormones to aquatic organisms is not clear. The PIs? preliminary data suggest that sediment-associated steroids remain bioavailable and, moreover, may represent the principle source of bioavailable steroidogenic compounds in aquatic systems. The proposed work is innovative as it represents the first study to examine how association with sediment alters the bioavailability of steroids to aquatic biota. The PIs will examine the physical and chemical factors responsible for estrogen and androgen fate and transformation in sediment as well as the routes by which macroorganisms are exposed to biologically-active steroid hormones. The results of the proposed research will provide a better understanding of the role of sediment in steroid transformation and biologic uptake and will support design of effective mitigation strategies in aquatic systems impacted by steroidogenic compounds. The objective of this application is to examine the role that sediments play in the environmental fate, transformation and bioavailability of steroidogenic compounds. The central hypothesis of this study is that sediment-associated steroids remain bioavailable. They plan to test their central hypothesis and accomplish the objective of this application by pursuing the following three specific aims: (1) determine the exposure routes by which steroids become bioavailable to the fathead minnow, a ubiquitous freshwater fish, (2) evaluate the physicochemical mechanisms governing steroid in sediment, and (3) validate their laboratory results with controlled field studies conducted in aquatic systems with known steroidogenic discharge. The educational and outreach plan for this project is focused on undergraduate and graduate student education as well as providing information to regional, national and international groups with an interest in endocrine-disrupting compounds. The proposed project represents a collaborative research effort between faculty at a research I University (University of Nebraska-Lincoln) and a predominantly undergraduate institution (University of Nebraska at Omaha). Educational modules outlining the methods and results of this research will be integrated into existing courses focused on contaminant fate and transport, environmental sampling methods, and toxicology taught by project investigators at the University of Nebraska-Lincoln and the University of Nebraska at Omaha. Research results and information on hormones in the environment will be disseminated to wastewater treatment plant operators, to the public through articles published in a University of Nebraska quarterly publication and an interactive website designed for a lay audience. International outreach will be achieved through a graduate student exchange program with the Corporación para Investigaciones Biológicas and the University of Antioquia in Medellin, Columbia.