C2H2 EAGER: Gadolinium Contamination in the Middle Rio Grande Valley: Understanding Environmental Fate and Human Exposure

气候变化不断升级的影响对全球淡水供应构成了前所未有的挑战，特别是在新墨西哥州等已经面临水压力的地区。这项建议解决了与医疗废物污染水资源有关的紧迫关切，特别是Gd，这是一种有毒元素，是磁共振成像所用造影剂的重要成分。本研究以新墨西哥州格兰德河谷中段的河流、溪流和地下水为研究对象，研究了人类活动的Gd在干旱半干旱地区地表和地下水资源中的去向及其对生态和人类健康的影响。这项研究包括实地观察、河流和地下水采样以及实验室实验工作。重点将是检查和追踪天然水中Gd的来源，并确定其在环境中的分布。将研究Gd对水处理设施的影响，并最终通过那些接受核磁共振检查的人的尿液对环境的影响，并将通过对人类消化/胃液的暴露和毒理学研究来确定其对人类健康的影响。这项研究的更广泛影响包括更好地了解医疗废物对水质和公众健康的影响。这项工作将为缓解计划提供急需的数据，并在促进环境可持续性和公共福利方面服务于国家利益。它还将吸引当地高中生参与水项目，其中许多人来自该地区的美洲原住民部落，以培养人们的兴趣，并增加对已经经历重大水资源压力的地区的水问题的了解。拟议的研究将解决有关医疗废物造成的Gd污染的关键研究问题，这些污染来自对比剂增强磁共振成像(MRI)液，其中含有对人类有害的元素Gd。在核磁共振液体中，Gd被螯合成一种化合物，使其对人类无害。然而，这种液体在尿液、成像后从体内排出，并通过污水和排汗处理厂进入地表和地下水系统。然后，Gd水物种被释放到自然环境中，在那里它们与自然材料和过程发生相互作用，这些过程可以改变物种的形成，使其成为生物可利用的。这项研究提供了对新墨西哥州格兰德河谷地表水和地下水中Gd的分布和形态的研究，并解决了对低浓度Gd的自然样品进行物种形成的分析挑战。它包括研究胃肠液对Gd形态及其毒性的影响。主要成果包括：(1)确定天然水(地表水和地下水)和位于阿尔伯克基和大象巴特河之间的格兰德河沿岸沉积物中Gd的浓度和种类；(2)评估人类通过饮用水源摄入Gd的途径和潜在的健康风险；以及(3)提高对Gd暴露的毒理学影响的认识，重点是胃肠道及其对人类健康的影响。这项工作将大大有助于我们了解Gd医疗废物在环境中构成的风险。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

The escalating impacts of climate change pose unprecedented challenges to freshwater supplies globally, particularly in areas already experiencing water stress, such as New Mexico. This proposal addresses a pressing concern related to the contamination of water resources by medical waste, specifically gadolinium (Gd), a toxic element that is an important component of contrast agents used in magnetic resonance imaging. This research focuses on the analysis of river, stream, and groundwater of the Middle Rio Grande Valley in New Mexico to investigate the fate of anthropogenic Gadolinium in surface and subsurface water resources of understudied arid to semiarid areas and its impact on ecologocal and human health. The research involves field observations and sampling of river and groundwaters and laboratory experimental work. A focus will be to examine and trace the sources of Gd in natural waters and determine its distribution in the environment. The impact of Gadolinium, released to water treatment facilities and ultimately to the environment via the urine of those who have under gone MRI, will be studied and its impact on human health will be determined through exposure and toxicological studies of human digestive/gastric fluids. Broader impacts of the reserach include improved understanding the consequences of medical waste on water quality and public health. The work will provide much needed data for mitigation plans and serve the national interest in promoting environmental sustainability and public welfare. It will also engage local high school students, many from Native American tribes in the area, in water projects to foster interest and to increase understanding of water issues in a region already experiencing significant water stress.The proposed research will address critical research questions regarding the fate, distribution, and toxicity of Gd contamination stemming from medical waste from contrast enhancing magnetic resonance imaging (MRI) fluids containing the element Gadolinium (Gd), a toxic element to humans. In MRI fluids, Gd is chelated into a compound that renders it harmless to humans. However, this fluid is excreted from the body in urine, post imaging, and enters surface and groundwater systems through sewars and sweage treatment plants. Gd aqueous species are then released into the natural environment where they experience interactions with natural materials and processes that can change the speciation allowing it to become bioavailable. This resaerch provides a study of the Gd distribution and speciation in New Mexico Rio Grande Valley surface and ground waters and addresses analytical challenges of speciating natural samples with low-concentrations of Gd. It includes investigation into the effects of gastrointestinal fluids on speciation of Gadolinium and its toxicity. Key outcomes include (1) characterizing the concentrations and species of Gd in natural waters (surface water and groundwater) and sediments along the Rio Grande between Albuquerque and Elephant Butte, (2) an assessment of human exposure pathways and potential health risks associated with Gd ingestion through drinking water sources, and (3) improved understanding of the toxicological implications of Gd exposure focusing on the gastrointestinal tract and its effects on human health. The work will contribute significantly to our understanding of the risks posed by Gd medical waste in the environment.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.