Project 5: Geochemical Processes Affecting Temporal Variablitity in Soil

项目 5：影响土壤时间变化的地球化学过程

基本信息

批准号：
8451460
负责人：
James P Shine
金额：
$ 23.37万
依托单位：
HARVARD SCHOOL OF PUBLIC HEALTH
依托单位国家：
美国
项目类别：
财政年份：
资助国家：
美国
起止时间：
至 2016-03-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8451460
关键词：
Accounting Adult Affect Animal Model Bangladesh Basic Science Biological Availability Biological Markers Biomedical Research Body Burden Boxing Carbon Carbonates Characteristics Chemicals Child Cohort Studies Collaborations Communities Complex County Data Diet Dose Environment Environmental Health Environmental Pollution Failure Food Funding Future Geology Goals Hand Heavy Metals Home environment House Dust Household Human Hydroxide Ion Hydroxides In Situ In Vitro Individual Infant Ingestion Iron Knowledge Laboratories Laboratory Study Lead Link Liquid substance Location Measures Metal exposure Metals Methodology Methods Mind Minerals Mining Modeling Mothers National Institute of Environmental Health Sciences Nature Occupations Oral Oral cavity Outcome Oxides Participant Pathway interactions Phase Policies Process Property Raman Spectrum Analysis Relative (related person)Research Risk Risk Assessment Route Sampling Scanning Electron Microscopy Science Site Soil Solutions Spectrum Analysis Stomach Superfund Tars Techniques Testing Time Toxic effect Toxicology Water Work X ray diffraction analysis X-Ray Diffraction base cohort exposed human population gastrointestinal system improved innovation insight interest neurodevelopment novel programs remediation research study simulation soil sampling sound superfund site tool toxic metal uptake wasting

项目摘要

The study of toxic heavy metals in the environment is challenging because metals are a natural component of our environment. As such, they have distinct biogeochemical cycles that govern their mobility, fate, and toxicity. A failure to understand these biogeochemical cycles will lead to a failure to adequately assess adverse impacts. Current risk assessment techniques for metals via the oral ingestion route are based on operationally defined tests which mimic the release of metals from soil in the human digestive system. A goal of this proposal is to be able to define the bioaccessibility of metals in geochemical terms, not based on operationally defined extraction methods. These goals will be tested through a combination of laboratory and in situ studies of metal-contaminated soils and mining wastes to characterize the interplay of processes that increase metal bioavailability over time and those that decrease metal bioavailability over time. Through these experiments, we will test whether the bioaccessibility of metals through oral ingestion can be predicted from the underlying speciation of metals and the characteristics of the soil itself. This study will bridge the current gap between geology and toxicology. Current risk assessment methods can determine if metals in a soil may exert risk, but not why. It is our intent to show that through the incorporation of a modest amount of geochemical analysis, we can greatly improve risk assessment for metals in soils by showing why some soils exert risk while other soils with similar levels of metals do not exert risk. In addition, with a similarly modest understanding of the temporal cycling of metals, we can show that bioaccessibility of metals in soils is not time invariant. With this knowledge, risk assessment can be proactive in understanding the nature of both current and future risks.

对环境中有毒重金属的研究具有挑战性，因为金属是我们环境的天然组成部分。因此，它们具有独特的生物地球化学循环，控制着它们的移动性、命运和毒性。不了解这些生物地球化学循环将导致无法充分评估不利影响。目前通过口服途径进行金属的风险评估技术是基于可操作定义的测试，这些测试模拟了人类消化系统中土壤中金属的释放。该提案的目标是能够用地球化学术语来定义金属的生物可访问性，而不是基于操作上定义的提取方法。这些目标将通过实验室和对金属污染土壤和采矿废物的现场研究相结合进行测试，以表征随着时间的推移增加金属生物利用度的过程和随着时间的推移降低金属生物利用度的过程的相互作用。通过这些实验，我们将测试是否可以根据金属的潜在形态和土壤本身的特征来预测通过口服摄入的金属的生物可及性。这项研究将弥合目前地质学和毒理学之间的差距。目前的风险评估方法可以确定土壤中的金属是否可能产生风险，但不能确定原因。我们的目的是表明，通过结合适量的地球化学分析，我们可以通过说明为什么某些土壤会产生风险而其他金属含量相似的土壤不会产生风险，从而极大地改进土壤中金属的风险评估。此外，通过对金属的时间循环有类似的适度了解，我们可以证明土壤中金属的生物可及性并不是随时间变化的。有了这些知识，风险评估就可以主动了解当前和未来风险的性质。