Climate impact on coastal ecosystem methylmercury: human exposure implications

气候对沿海生态系统甲基汞的影响：人类接触的影响

• 批准号: 8388569
• 负责人: Celia Y Chen
• 金额: $ 39.3万
• 依托单位: DARTMOUTH COLLEGE
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-09-26 至 2015-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8388569
• 关键词: Address; Biomass; Carbon; Child; Climate; Complex; Consumption; Data; Ecosystem; Eutrophication; Exposure to; Fisheries; Fishes; Food; Food Webs; Future; Goals; Hazardous Substances; Health; Human; Individual; International; Laboratory Study; Link; Location; Manuscripts; Marines; Mercury; Methylation; Methylmercury Compounds; Mexico; Modeling; Nutrient; Outcome; Oxidation-Reduction; Peer Review; Phytoplankton; Population; Pregnant Women; Production; Publications; Relative (related person); Research; Research Personnel; Review Literature; Risk; Shellfish; Site; Source; Staging; Study models; Techniques; Temperature; Testing; Toxin; Variant; Water; Writing; base; bioaccumulation; climate change; exposed human population; field study; gulf coast; innovation; interest; meetings; public health relevance; tool

DESCRIPTION (provided by applicant) Mercury (Hg) is the third most important contaminant on the CERCLA Priority List of Hazardous Substances (2011) and its organic and toxic form, methyl mercury (MeHg), is a potent toxin with human health effects. Marine fisheries particularly in coastal ecosystems are dominant sources of human exposure to MeHg through consumption of marine fish and shellfish. 48 states in the U.S. have issued advisories against consumption of fish due to MeHg, including coastal advisories for the Atlantic Coast and the Gulf of Mexico. Sub-populations most at risk for exposure include pregnant women and children and subsistence fishers. To date, research on MeHg fate has not investigated the interaction of climate change variables such as temperature and nutrient/carbon loading even though they are likely to have synergistic effects on the formation and transfer of MeHg to the fish and shellfish that humans consume. The investigators therefore propose to examine in detail individual and combined effects of these factors using laboratory and field studies, and through integrative modeling to examine their overall impact on human exposure to MeHg. The following three aims are the basis for their primary hypotheses: Aim 1: Determine the effects of temperature, nutrient and carbon loading on the net MeHg formation in sediments and the associated net inputs of MeHg to the water column in coastal ecosystems. Aim 2: Determine the interactive effects of temperature and nutrient supply/ecosystem eutrophication on bioaccumulation of MeHg by primary producers, and transfer between primary and secondary consumers in estuarine food webs. Aim 3: Predict how climate-induced changes in MeHg bioaccumulation in coastal food webs will increase exposure and risk to sensitive populations. The investigators will apply innovative experimental and field techniques to investigate the interactions between these factors on MeHg fate in estuaries. They will investigate sites in northern and southern latitudes to determine the influence of a natural range of temperatures on MeHg production and bioaccumulation in estuarine ecosystems. Finally, they will use experimental and field data to adapt and parameterize an existing MeHg biogeochemistry and bioaccumulation model to include variation in temperature and nutrient/carbon loading. These tools will allow them to predict the effects of climate change variables on MeHg production and transfer to fish to estimate the net effect of these changes on human exposure. Public Health Relevance: Methyl mercury (MeHg) is a global toxin impacting human health, and marine ecosystems are dominant sources of human exposure through consumption of marine fish and shellfish. Estuarine ecosystems are both a major source of MeHg to marine food webs and locations where climate induced changes and nutrient and carbon loading will have complex effects on the production, transfer, and bioaccumulation of MeHg. The investigators will examine these interactive effects which are critical to understanding the future impact of MeHg on human exposure and health.

描述（由申请人提供） 汞 (Hg) 是 CERCLA 危险物质优先清单（2011 年）中第三重要的污染物，其有机有毒形式甲基汞 (MeHg) 是一种对人类健康有影响的强效毒素。 海洋渔业，特别是沿海生态系统中的渔业，是人类通过食用海洋鱼类和贝类接触甲基汞的主要来源。 美国 48 个州发布了禁止食用甲基汞鱼类的警告，其中包括大西洋海岸和墨西哥湾的沿海警告。 暴露风险最大的亚人群包括孕妇、儿童以及自给渔民。 迄今为止，关于甲基汞归宿的研究尚未调查温度和营养物/碳负荷等气候变化变量的相互作用，尽管它们可能对甲基汞的形成和向人类食用的鱼类和贝类的转移产生协同效应。因此，研究人员建议通过实验室和现场研究详细检查这些因素的个体和综合影响，并通过综合模型来检查它们对人类接触甲基汞的总体影响。以下三个目标是他们主要假设的基础： 目标 1：确定温度、营养物和碳负荷对沉积物中甲基汞净形成以及沿海生态系统水体中相关甲基汞净输入的影响。 目标 2：确定温度和养分供应/生态系统富营养化对初级生产者的甲基汞生物累积以及河口食物网中初级和次级消费者之间转移的交互影响。 目标 3：预测气候引起的沿海食物网中甲基汞生物累积变化将如何增加敏感人群的暴露和风险。 研究人员将应用创新的实验和现场技术来研究这些因素之间的相互作用对河口甲基汞命运的影响。 他们将调查北纬和南纬的地点，以确定自然温度范围对河口生态系统中甲基汞生产和生物累积的影响。 最后，他们将使用实验和现场数据来调整和参数化现有的甲基汞生物地球化学和生物累积模型，以包括温度和养分/碳负荷的变化。这些工具将使他们能够预测气候变化变量对甲基汞生产和向鱼类转移的影响，以估计这些变化对人类接触的净影响。 公共卫生相关性：甲基汞 (MeHg) 是一种影响人类健康的全球性毒素，海洋生态系统是人类通过食用海洋鱼类和贝类而接触甲基汞的主要来源。河口生态系统既是海洋食物网甲基汞的主要来源，也是气候引起的变化以及营养物和碳负荷将对甲基汞的生产、转移和生物累积产生复杂影响的地区。 研究人员将检查这些互动效应，这对于了解未来至关重要 甲基汞对人类接触和健康的影响。