title: Characterization of coal fly ash nanoparticles and induced oxidative DNA damage in human peripheral blood mononuclear cells.
abstract: The nano-sized particles present in coal fly ash (CFA) were characterized through the X-ray diffraction (XRD), transmission and scanning electron microscopy (TEM, SEM), atomic force microscopy (AFM) and Fourier transform infrared spectroscopy (FTIR) analyses. The XRD data revealed the average crystallite size of the CFA nanoparticles (CFA-NPs) as 14 nm. TEM and SEM imaging demonstrated predominantly spherical and some polymorphic structures in the size range of 11 to 25 nm. The amount of heavy metal associated with CFA particles (μg/g) were determined as Fe (34160.0±1.38), Ni (150.8±0.78), Cu (99.3±0.56) and Cr (64.0±0.86). However, the bioavailability of heavy metals in terms of percent release was in the order as Cr>Ni>Cu>Fe in CFA-dimethyl sulfoxide (DMSO) extract. The comet and cytokinesis blocked micronucleus (CBMN) assays revealed substantial genomic DNA damage in peripheral blood mononuclear (PBMN) cells treated with CFA-NPs in Aq and DMSO extracts. About 1.8 and 3.6 strand breaks per unit of DNA were estimated through alkaline unwinding assay at 1:100 DNA nucleotide/CFA ppm ratios with the Aq and DMSO extracts, respectively. The DNA and mitochondrial damage was invariably greater with CFA-DMSO extract vis-à-vis -Aq extract. Generation of superoxide anions (O(2)•(-)) and intracellular reactive oxygen species (ROS) through metal redox-cycling, alteration in mitochondrial potential and 8-oxodG production elucidated CFA-NPs induced oxidative stress as a plausible mechanism for CFA-induced genotoxicity.
authors.affiliation: Department of Zoology, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia.
authors.forename: Sourabh
authors.initials: S
authors.lastname: Dwivedi
authors.forename: Quaiser
authors.initials: Q
authors.lastname: Saquib
authors.forename: Abdulaziz A
authors.initials: AA
authors.lastname: Al-Khedhairy
authors.forename: Al-Yousef Sulaiman
authors.initials: AY
authors.lastname: Ali
authors.forename: Javed
authors.initials: J
authors.lastname: Musarrat
mesh_terms: D002478:Cells, Cultured; D060729:Coal Ash / Q000009:adverse effects* / Q000032:analysis; D020552:Comet Assay; D004249:DNA Damage / Q000187:drug effects*; D003849:Deoxyguanosine / Q000031:analogs & derivatives / Q000138:chemical synthesis; D006801:Humans; D007963:Leukocytes, Mononuclear / Q000737:chemistry / Q000187:drug effects*; D053758:Nanoparticles / Q000009:adverse effects* / Q000032:analysis; D018384:Oxidative Stress / Q000187:drug effects*; D010316:Particle Size; D013481:Superoxides / Q000009:adverse effects / Q000032:analysis
chemical_list: D060729:Coal Ash; D013481:Superoxides; D003849:Deoxyguanosine