Superfund Research Program
Dynamic Exposure Pathways Under Conditions of Environmental Emergencies
Project Leader: Anthony Knap
Co-Investigators: Terry L. Wade, Mikyoung Jun, James M. Kaihatu
Grant Number: P42ES027704
Funding Period: 2017-2022
- Project Summary
Project Summary (2017-2022)
The Texas A&M University Superfund Research Program (TAMU SRP) Center aims to mitigate human exposure to hazardous substances, specifically exposure to mixtures of contaminants that are redistributed by manmade or natural environmental disasters. This project investigates 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 TAMU SRP Center is focused on the Galveston Bay and Houston Ship Channel (GB/HSC), an area where the 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.
The expertise of the research team forms a solid foundation to test their 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.
This project is critical to the overall TAMU SRP Center as it determines contaminant loading of marine sediments from historical data and new chemical analyses, establishes the current background of contaminants in the soils of key areas identified by local communities, and collects and analyzes samples before and after storm events. The researchers work with the Community Engagement Core to determine areas of concern to communities and then sample soils from land and marine sediments. They 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, the research team is determining the potential transformation of compounds in sediments as they are transported to land. Furthermore, they develop predictive hurricane and flood models to determine the extent of hazardous contaminant mobilization during environmental emergencies. These models are 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, the researchers are performing targeted and non-targeted analyses of contaminants and characterizing exposures under realistic environmental conditions. In addition, the project provides real-world contaminant mixtures of known and unknown hazardous pollutants to other cores and projects to determine the toxicity and risk to communities.