title: Role of metals in free radical generation and genotoxicity induced by airborne particulate matter (PM2.5) from Pune (India).
abstract: In the present study, metal-facilitated free radical generation in particulate matter (PM) and its association with deoxyribonucleic acid (DNA) damage were studied. The examined data showed that the concentration of fine PM in Pune exhibited seasonal variations. Inductively coupled plasma-atomic emission spectrometry (ICP-AES) was used to examine the metal composition, which showed the presence of metals such as Cu, Zn, Mn, Fe, Co, Cr, Pb, Cd, and Ni. Fe metal was present in the highest concentrations in both the seasons, followed by Zn. The scanning electron microscopy-energy-dispersive spectrometer (SEM-EDS) results also demonstrated that the fine PM particles deposited in summer samples were less than those of winter samples, suggesting that the PM load in winter was higher as compared to that in summer. Elemental mapping of these particles substantiates deposition of metals as Fe, Zn, etc. on particles. The electron paramagnetic species (EPR) technique was utilized for free radical detection, and plasmid DNA assay was utilized to study the genotoxicity of ambient fine PM. Obtained g values show the presence of radicals in PM samples of Pune. PM contains the C-centered radical with a vicinal oxygen atom (g = 2.003). In addition to this, the g value for Fe was also observed. Therefore, we intend that the radicals related with fine PM comprise metal-mediated radicals and produce DNA damage. The plasmid DNA assay results indicated that the TM50values (toxic mass of PM causing 50 % of plasmid DNA damage) of PM exhibited seasonal variations with higher TM50values for summer and lower TM50values during winter.
authors.affiliation: Department of Chemistry, Savitribai Phule Pune University, Pune, 411 007, India.
authors.forename: Suman
authors.initials: S
authors.lastname: Yadav
authors.affiliation: Department of Chemistry, Savitribai Phule Pune University, Pune, 411 007, India.
authors.forename: Rohi
authors.initials: R
authors.lastname: Jan
authors.affiliation: Department of Chemistry, Savitribai Phule Pune University, Pune, 411 007, India.
authors.forename: Ritwika
authors.initials: R
authors.lastname: Roy
authors.affiliation: Department of Chemistry, Savitribai Phule Pune University, Pune, 411 007, India. pgsatsangi@chem.unipune.ac.in.
authors.forename: P Gursumeeran
authors.initials: PG
authors.lastname: Satsangi
mesh_terms: D010584:Bacteriophage phi X 174 / Q000187:drug effects / Q000235:genetics; D004249:DNA Damage; D004279:DNA, Viral / Q000235:genetics; D004784:Environmental Monitoring; D005609:Free Radicals / Q000032:analysis / Q000737:chemistry; D007194:India; D019216:Metals, Heavy / Q000032:analysis* / Q000737:chemistry; D009153:Mutagens / Q000032:analysis* / Q000737:chemistry / Q000494:pharmacology; D010100:Oxygen / Q000032:analysis / Q000737:chemistry; D010316:Particle Size; D052638:Particulate Matter / Q000032:analysis* / Q000737:chemistry / Q000494:pharmacology; D012621:Seasons
chemical_list: D004279:DNA, Viral; D005609:Free Radicals; D019216:Metals, Heavy; D009153:Mutagens; D052638:Particulate Matter; D010100:Oxygen
keywords: EPR; Free radicals; Metal concentration; Oxidative DNA damage; SEM-EDS; Source apportionment