Environmentally persistent free radicals (EPFRs) are formed on surfaces of transition metal oxides when molecules chemisorb on them. Electron transfer from the molecule to the metal results in reduction of the metal and the creation of spin density on the organic molecular adsorbate, i.e., formation of the EPFR. These """"""""interfacial pollutants"""""""" are relatively stable (i.e., persisting for hours or days), so they can enter the environment and have deleterious health effects. Moreover, these systems are particularly prevalent at Superfund sites, so it is essential that they be studied and characterized in order to understand their roles in human health impacts in the vicinity of Superfund sites. However, these systems are complex and difficult to characterize, so we have designed this project to understand the detailed structural and chemical transformations that are responsible for their creation. Specifically, this project explores the physical and chemical characteristics of these particle-bound pollutants primarily using x-ray spectroscopy and TEM analysis. There are three Specific Aims: (1) Develop methods for controlled, reproducible generation of metal oxide-containing nanoparticles as surrogates of nanoclusters found in real-world environments, (2) Characterize the metal nanoparticles, structurally and electronically, and (3) Determine the surface processes and interactions of CHCs that lead to the formation of persistent free radicals and other toxic pollutants. This project characterizes the electron properties of the particle surface, which is indispensable for the other projects. Collaboration with Project 1 will lead to understanding of the structure and electronic properties of the EPFRs, which will allow those researchers to understand the factors affecting EPFR formation and reactivity. It generates background for studies of EPFRs in Superfund soils in Project 3. It similarly provides the chemistry necessary to understand the health effects induced by inhalation of EPFRs demonstrated in biomedical projects 2, 4, and 5. Finally, the structural characterization of the metal oxide particles and the surface-bound molecules will be indispensable for both the Computational Core, as well as the Materials Core.

Public Health Relevance

Environmentally persistent free radicals associated with Superfund particulate matter may be a major source of the toxicity of the particles. Because these interfacial pollutants are composed of two components that are relatively benign individually, they are currently neither adequately recognized, nor characterized.

Agency
National Institute of Health (NIH)
Institute
National Institute of Environmental Health Sciences (NIEHS)
Type
Hazardous Substances Basic Research Grants Program (NIEHS) (P42)
Project #
5P42ES013648-06
Application #
8659466
Study Section
Special Emphasis Panel (ZES1-SET-V)
Project Start
Project End
Budget Start
2014-04-01
Budget End
2015-03-31
Support Year
6
Fiscal Year
2014
Total Cost
$197,587
Indirect Cost
$59,641
Name
Louisiana State University A&M Col Baton Rouge
Department
Type
DUNS #
075050765
City
Baton Rouge
State
LA
Country
United States
Zip Code
70803
Reed, James R; Backes, Wayne L (2017) Physical Studies of P450-P450 Interactions: Predicting Quaternary Structures of P450 Complexes in Membranes from Their X-ray Crystal Structures. Front Pharmacol 8:28
Shrestha, Bishwas; You, Dahui; Saravia, Jordy et al. (2017) IL-4R? on dendritic cells in neonates and Th2 immunopathology in respiratory syncytial virus infection. J Leukoc Biol 102:153-161
Connick, John Patrick; Reed, James R; Backes, Wayne L (2017) Characterization of interactions among CYP1A2, CYP2B4, and NADPH-cytochrome P450 reductase: Identification of specific protein complexes. Drug Metab Dispos :
Patterson, Matthew C; DiTusa, Mark F; McFerrin, Cheri A et al. (2017) Formation of environmentally persistent free radicals (EPFRs) on ZnO at room temperature: Implications for the fundamental model of EPFR generation. Chem Phys Lett 670:5-10
Oyana, Tonny J; Lomnicki, Slawomir M; Guo, Chuqi et al. (2017) A Scalable Field Study Protocol and Rationale for Passive Ambient Air Sampling: A Spatial Phytosampling for Leaf Data Collection. Environ Sci Technol 51:10663-10673
Feld-Cook, Elisabeth E; Bovenkamp-Langlois, Lisa; Lomnicki, Slawo M (2017) Effect of Particulate Matter Mineral Composition on Environmentally Persistent Free Radical (EPFR) Formation. Environ Sci Technol 51:10396-10402
Deese, Rachel D; Weldeghiorghis, Thomas K; Haywood, Benjamin J et al. (2017) Influence of surfactants and humic acids on Artemia Franciscana's embryonic phospho-metabolite profile as measured by 31P NMR. Aquat Toxicol 186:188-195
Jaligama, Sridhar; Saravia, Jordy; You, Dahui et al. (2017) Regulatory T cells and IL10 suppress pulmonary host defense during early-life exposure to radical containing combustion derived ultrafine particulate matter. Respir Res 18:15
Chuang, Gin C; Xia, Huijing; Mahne, Sarah E et al. (2017) Environmentally Persistent Free Radicals Cause Apoptosis in HL-1 Cardiomyocytes. Cardiovasc Toxicol 17:140-149
Deese, Rachel D; LeBlanc, Madeline R; Cook, Robert L (2016) Surfactant toxicity to Artemia Franciscana and the influence of humic acid and chemical composition. Environ Chem 13:507-516

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