Dynamic exposure pathways under conditions of environmental emergencies

项目1

Project 1 ABSTRACT The proposed Texas A&M University Superfund Research Center aims to mitigate human exposure to hazardous substances, specifically exposure to mixtures of contaminants that are redistributed by manmade or natural environmental disasters. Project 1 will investigate the redistribution of contaminated sediments from both soils and marine sediments as a consequence of natural disasters such as floods and storms. Changing climate, human-induced land subsidence, and rising sea levels have increased the vulnerability of coastal areas to environmental disasters worldwide. The proposed Center is focused on the Galveston Bay and Houston Ship Channel (GB/HSC), an area where our group has had decades of experience analyzing sediments, tissues of marine organisms, and water samples for legacy contaminants. The GB/HSC area includes the 4th largest metropolitan city in the US and is located near one of the most contaminated marine/coastal areas, with 22 listed or proposed Superfund sites. The area is prone to environmental disasters such as floods, tropical storms, and hurricanes; large storms may redistribute contaminants that are currently bound to sediments throughout the marine area and cause widespread land deposition of contaminants via storm surge and flooding. Our expertise forms a solid foundation to test our central hypothesis that characterizing current sediment and soil contaminant levels, sediment transport, redistribution, and transformation caused by extreme weather emergency events will identify exposure pathways of complex contaminated mixtures and inform methods to predict, respond to, and mitigate these exposures to protect the health of affected populations. Project 1 is critical to the overall Center as it will determine contaminant loading of marine sediments from historical data and new chemical analyses, establish the current background of contaminants in the soils of key areas identified by local communities, and collect and analyze samples before and after storm events. We will work with the Community Engagement Core to determine areas of concern to communities and then sample soils from land and marine sediments. We will also obtain already collected samples from a wide network of State and Federal government collaborators, and analyze all samples for hazardous contaminants of concern to Superfund. Through laboratory studies, we will determine the potential transformation of compounds in sediments as they are transported to land. Furthermore, we will develop predictive hurricane and flood models to determine the extent of hazardous contaminant mobilization during environmental emergencies. These models will be adaptable to other areas in the US and worldwide where similar concerns exist with respect to environmental emergencies that involve possible redistribution of sediments contaminated with hazardous chemicals. Working with the Exposure Science Core, Project 1 will perform targeted and non-targeted analyses of contaminants and characterize exposures under realistic environmental conditions. In addition, Project 1 will provide real-world contaminant mixtures of known and unknown hazardous pollutants to other Cores and Projects to determine the toxicity and risk to communities.