Project Summary (2020-2025)

Nearly 53 million people live within three miles of a Superfund remediation site. Superfund sites contain a wide variety of pollutants, including organic chemicals, metals, carbonaceous material, and silica. Although each component is capable of damage to organisms, their potential to combine into unique hazardous agents has been understudied. Interestingly, when these agents are present together, particularly during thermal treatment (TT), they combine to form particulate matter (PM) with chemisorbed free radicals that persist in the environment and are active in biological systems (environmentally persistent free radicals or EPFRs). EPFRs are produced during TT of hazardous wastes. Nearly 30 percent of all Superfund sites (non-groundwater) are remediated by TT. EPFR concentrations near Superfund sites range from 1x10^18 - 4x10^19 radicals/g of PM. Colfax, Louisiana hosts a hazardous waste TT facility, which disposes of fireworks, explosives, and military ordnances. Sixty-eight percent of Colfax's residents are African American, and the median household income is $26,149, indicating the community's institutional vulnerability. This project is measuring concentrations of EPFRs to estimate human exposure in Colfax. The researchers also are measuring other components of combustion-generated PM across size fractions and detonation-related noise as a co-stressor. This project addresses the three overarching objectives of the Superfund Research Program's Strategic Plan. By characterizing EPFRs emitted from this TT site handling hazardous wastes, including waste from Superfund sites, the researchers are addressing an issue of high relevance to inform solution-oriented research. They are maximizing the impact of the Louisiana State University SRP's investments by coordinating with the Research Translation component of the Administrative Core to facilitate translation of results to actionable information for the Colfax community. Further, they are coordinating with the Community Engagement Core (CEC) to implement their community-based participatory research model. This novel approach fosters innovation by designing and implementing a field sampling plan for size distributions of EPFRs, size distributions of other PM components, and noise as a co-stressor. The overarching hypothesis of this research is that EPFRs are produced in measurable quantities in PM during TT so that outdoor and in-home EPFR exposure increases with decreasing distance to the source. In Aim 1, the researchers are partnering with the Colfax community on plans for assessing exposure to hazardous air pollutants from hazardous waste TT emissions and determining whether collaboration will promote community empowerment and engagement on public health advocacy. This work is being conducted in partnership with two community organizations and in coordination with the CEC. Aim 2 seeks to characterize Colfax residents' exposures to EPFRs in PM by size distribution and composition, how exposures change with distance downwind of the TT facility, and how exposures correlate to detonation-related noise. Aim 3 seeks to characterize in-home concentrations of EPFRs and additional chemical and non-chemical stressors among Colfax study participants.