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Updated: Mar 19, 2026
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Free Radicals in Chemical Biology: from Chemical Behavior to Biomarker Development
Published on: April 15, 2013
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Addressing Emerging Risks: Scientific and Regulatory Challenges Associated with Environmentally Persistent Free
Tammy R Dugas1, Slawomir Lomnicki2, Stephania A Cormier3
1Department of Comparative Biomedical Sciences, LSU School of Veterinary Medicine, Baton Rouge, LA 70803, USA. tammydugas@lsu.edu.
Summary
Environmentally Persistent Free Radicals (EPFRs) form on particulate matter (PM) during thermal processes. These radicals pose risks near Superfund sites due to their persistence and association with health issues.
Area of Science:
- Environmental Science
- Toxicology
- Chemistry
Background:
- Airborne fine and ultrafine particulate matter (PM) are generated by thermal processes like fuel combustion and waste decomposition.
- Residents near Superfund sites face exposure to PM via dust, soil ingestion, and emissions from soil treatment.
- Epidemiological studies link PM exposure to increased risks of cardiovascular and pulmonary diseases.
Purpose of the Study:
- To review evidence supporting the formation and environmental significance of Environmentally Persistent Free Radicals (EPFRs).
- To address the lack of risk assessment methodologies for EPFRs.
- To discuss challenges in regulating EPFRs as emerging contaminants.
Main Methods:
- Review of existing epidemiological and scientific literature on PM, combustion, and radical formation.
- Analysis of EPFR presence in ambient air PM2.5 and combustion-derived PM.
- Identification of knowledge gaps in EPFR risk assessment and regulation.
Main Results:
- Incomplete combustion leads to organic pollutants adsorbing onto PM, forming metal-radical complexes capable of ROS production.
- These complexes can persist as Environmentally Persistent Free Radicals (EPFRs).
- Low-temperature thermal treatment of soils may increase EPFR concentrations near Superfund sites.
Conclusions:
- EPFRs are an emerging environmental contaminant associated with thermal processes and PM.
- There is a critical need for specific risk assessment methodologies and regulatory strategies for EPFRs.
- Further research is required to understand and mitigate the health and environmental impacts of EPFRs.
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