title: Toxicological characterization of the landfill leachate prior/after chemical and electrochemical treatment: a study on human and plant cells.
abstract: In this research, toxicological safety of two newly developed methods for the treatment of landfill leachate from the Piškornica (Croatia) sanitary landfill was investigated. Chemical treatment procedure combined chemical precipitation with CaO followed by coagulation with ferric chloride and final adsorption by clinoptilolite. Electrochemical treatment approach included pretreatment with ozone followed by electrooxidation/electrocoagulation and final polishing by microwave irradiation. Cell viability of untreated/treated landfill leachate was examined using fluorescence microscopy. Cytotoxic effect of the original leachate was obtained for both exposure periods (4 and 24 h) while treated samples showed no cytotoxic effect even after prolonged exposure time. The potential DNA damage of the untreated/treated landfill leachate was evaluated by the comet assay and cytokinesis-block micronucleus (CBMN) assay using either human or plant cells. The original leachate exhibited significantly higher comet assay parameters compared to negative control after 24 h exposure. On the contrary, there was no significant difference between negative control and chemically/electrochemically treated leachate for any of the parameters tested. There was also no significant increase in either CBMN assay parameter compared to the negative control following the exposure of the lymphocytes to the chemically or electrochemically treated landfill leachate for both exposure periods while the original sample showed significantly higher number of micronuclei, nucleoplasmic bridges and nuclear buds for both exposure times. Results suggest that both methods are suitable for the treatment of such complex waste effluent due to high removal efficiency of all measured parameters and toxicological safety of the treated effluent.
authors.affiliation: Institute for Medical Research and Occupational Health, Mutagenesis Unit, 10000 Zagreb, Croatia. Electronic address: vgaraj@imi.hr.
authors.forename: Vera
authors.initials: V
authors.lastname: Garaj-Vrhovac
authors.forename: Višnja
authors.initials: V
authors.lastname: Oreščanin
authors.forename: Goran
authors.initials: G
authors.lastname: Gajski
authors.forename: Marko
authors.initials: M
authors.lastname: Gerić
authors.forename: Damir
authors.initials: D
authors.lastname: Ruk
authors.forename: Robert
authors.initials: R
authors.lastname: Kollar
authors.forename: Sandra
authors.initials: S
authors.lastname: Radić Brkanac
authors.forename: Petra
authors.initials: P
authors.lastname: Cvjetko
mesh_terms: D002460:Cell Line; D020552:Comet Assay; D017523:Croatia; D004784:Environmental Monitoring; D006801:Humans; D015162:Micronucleus Tests; D010944:Plants / Q000187:drug effects*; D012037:Refuse Disposal / Q000379:methods*; D064091:Waste Disposal Facilities; D014874:Water Pollutants, Chemical / Q000633:toxicity*
chemical_list: D014874:Water Pollutants, Chemical
keywords: AO; APDC; Allium cepa; BOD; CBMN; COD; Chemical treatment; Cytogenotoxicity; EC; Electrochemical treatment; EtBr; HPBL; Human lymphocytes; LPO; Landfill leachate; MAV; MN; MNi; NBUD; NPB; ROS; SCGE; SS; TDS; TOC; acridine orange; ammonium-pyrolidinedithiocarbamate; biochemical oxygen demand; chemical oxygen demand; cytokinesis-block micronucleus assay; electrical conductivity; ethidium bromide; human peripheral blood lymphocyte; lipid peroxidation; maximal allowed values; micronuclei; micronucleus; nuclear bud; nucleoplasmic bridge; reactive oxidative species; single cell gel electrophoresis assay; suspended solids; total dissolved solids; total organic carbon