title: Determination of TiO2, ZrO2, and Al2O3 nanoparticles on genotoxic responses in human peripheral blood lymphocytes and cultured embyronic kidney cells.
abstract: In this study a genotoxic evaluation of titanium dioxide (TiO2, 2.3 nm), zirconium oxide (ZrO2, 6 nm), aluminum oxide (Al2O3, 16.7 nm) nanoparticles (NP) and their ionic forms was conducted using human peripheral blood lymphocytes and cultured human embryonic kidney (HEK293) cells by means of a modified alkaline comet assay with/without the formamidopyrimidine-DNA glycosylase (Fpg) and endonuclease III (Endo III) enzymes. Modifications to the comet assay by using lesion-specific endonucleases, such as Endo III and Fpg, detect DNA bases with oxidative damage. Both human peripheral blood lymphocytes and cultured embryonic kidney cells were incubated with TiO2, ZrO2, or Al2O3 NP at concentrations of 1, 10, or 100 μg/ml. Our results showed no significant induction in DNA damage by the comet assay with/without the Endo III and Fpg enzymes at all concentrations of ZrO2 and Al2O3. In the case of TiO2 NP only the highest concentration of 100 μg/ml significantly induced a genotoxic response. Data thus indicate that both ZrO2 and Al2O3 NP were not genotoxic in our system and in the case of TiO2 the lowest-observed-adverse-effect level (LOAEL) for genotoxicity was 100 μg/ml. Evidence indicates that these metallic NP are considered safe in light of the fact that no genotoxicity was noted with ZrO2 and Al2O3 and that the highest TiO2 concentration is not environmentally relevant.
authors.affiliation: a Department of Biology , Faculty of Sciences, Akdeniz University , Antalya , Turkey.
authors.forename: Eşref
authors.initials: E
authors.lastname: Demir
authors.forename: Durmuş
authors.initials: D
authors.lastname: Burgucu
authors.forename: Fatma
authors.initials: F
authors.lastname: Turna
authors.forename: Sezgin
authors.initials: S
authors.lastname: Aksakal
authors.forename: Bülent
authors.initials: B
authors.lastname: Kaya
mesh_terms: D000537:Aluminum Oxide / Q000737:chemistry / Q000633:toxicity*; D002470:Cell Survival; D002478:Cells, Cultured; D020552:Comet Assay; D006801:Humans; D007668:Kidney / Q000166:cytology*; D008214:Lymphocytes / Q000187:drug effects*; D053768:Metal Nanoparticles / Q000737:chemistry / Q000633:toxicity*; D014025:Titanium / Q000737:chemistry / Q000633:toxicity*; D015040:Zirconium / Q000737:chemistry / Q000633:toxicity*
chemical_list: C009495:titanium dioxide; D015040:Zirconium; D014025:Titanium; D000537:Aluminum Oxide; C028541:zirconium oxide