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Biomarkers of Oxidative Stress in Aquatic Organisms and Risk Assessment. The Examples of

Biomarkers of Oxidative Stress in Aquatic Organisms and Risk Assessment. The Examples of Antioxidant Enzyme Activities and Lipid Peroxidation. Vlahogianni Thomais, Valavanidis Athanasios. Department of Chemistry, University of Athens, Greece. Bioaccumulation &

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Biomarkers of Oxidative Stress in Aquatic Organisms and Risk Assessment. The Examples of

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  1. Biomarkers of Oxidative Stress in Aquatic Organisms and Risk Assessment. The Examples of Antioxidant Enzyme Activities and Lipid Peroxidation. Vlahogianni Thomais, Valavanidis Athanasios Department of Chemistry, University of Athens, Greece

  2. Bioaccumulation & Biological effect monitoring Biological effect, Health & ecosystem monitoring Chemical monitoring INDICATORS OF EFFECTS Biomarkers of effects Injury Population & Community parameters SOURCES Concentrations in media (external dose) Emission rates INDICATORS OF EXPOSURE Bioaccumulation markers Biomarkers of exposure Environmental factors modifying exposure Environmental factors modifying susceptibility Other causes Environmental Monitoring Methods

  3. Contaminant Mixtures UV & Visible Radiation Uptake Import by adsorptive Endocytosis & Phagocytosis Particulates Speciation, Binding & Transport Uptake Trans-Membrane Diffusion Toxicity & Cell injury Physicochemical Behavior, Activation & Detoxication Exposure Biomarkers UV & Visible Radiation Pathological Endpoints Prognostic Biomarkers Ecological Impact Mortality, Reduced Fecundity Increased Susceptibility to Other Stresses & Loss of Diversity Human Health Impact Toxicity & Diseases via food chain Major Processes in Pollutant Impact

  4. SHORT TERM Biological Complexity, Response LONG TERM Time & Biological Significance Physical factors & Biological Agents Pollutant Chemicals & Radionuclides Molecular & Cellular Tissue Organs Individual animal EARLY BIOMARKER SIGNALS LATER EFFECTS Biological Effects & Ecological Relevance

  5. Lethal effects Environmental Pollutants Sublethal effects Changes in enzyme activities Damage to DNA, proteins & membrane lipids Effects on behavioral, reproductive & immunological activities Environmental Pollutants & Effects to Organisms

  6. Freshwater Ecosystems Wide geographical distribution Easy to collect Filter-feeding organisms Bioconcentrate xenobiotics Easily transferred from control to contaminated areas Sentinel Species Bioindicators Marine Ecosystems Reflect changes in pollution status of the aquatic environment Biomonitoring Mussels: Bioindicators for Aquatic Pollution

  7. Organic & Inorganic Pollutants ROS Polyclic Aromatic Hydrocarbons Organochlorine & Organophoshate pesticides Polychlorinated biphenyls Aromatic diols Quinones Nitroaromatics Aromatic hydroxylamines Dioxins Bipyridyls Transition metal chelates Redox Molecular Biomarkers Of Oxidative Stress Aquatic Organisms Potential Lipid Peroxidation Enzyme Activities DNA Damage Protein Degradation * ROS: Reactive Oxygen Species Chemical Pollutants & Oxidative Stress

  8. Anthropogenic activities Solar radiation Η2Ο2 Environmental factors Ο2─ Η2Ο2 Μn+ Ο2─ Oxidative DNA damage Metal competition ΗΟ MT Protein damage Proteins CAT Μn+ SOD Changes in Enzyme activities Metal transport Lipid Peroxidation PUFAs Ions diffusion Organic pollutants Metal complexation Metals Temperature Salinity ROS & biochemical & physiological responses in cells of aquatic organisms

  9. SOD Superoxide dismutase (SOD)

  10. CAT Catalase (CAT)

  11. Initiation Propagation Antioxidants Oxidized Antioxidants Inhibition Degradation of Lipid Peroxides Termination Aldehydes and other products LH: lipid substrate L•: lipid radical LOOH: lipid hydroperoxide LOO•: lipid peroxyl radical NRP: nonradical product Biomarkers of Oxidative stress Lipid Peroxidation (LPO)

  12. PAHs Metals (Fe,Cd,Cu,Cr,Ni,Pb) 3 polluted sites (1, 2, 3) in the Saronikos gulf Superoxide dismutase (SOD) activity Catalase (CAT) activity Lipid Peroxidation (LPO) levels Biomarkers of Oxidative Stress Sampling Reference site (4) “Clean” marine farm at 4 seasons Measurements of PAHs and Metal concentrations in mussel tissues revealed elevated levels of chemical pollution at Sites 1 & 2 Oxidative Stress in Mussels from the Saronikos gulf (Greece)

  13. Mantle tissue Gills tissue Representative chart for PAHs concentrations in mussel tissues

  14. Mantle tissue Gills tissue Results for SOD activity

  15. Mantle tissue Gills tissue Results for CAT activity

  16. Gills tissue Mantle tissue Results for Lipid Peroxidation levels

  17. Conclusions • Pollution in coastal waters of Saronikos gulf • causes moderate levels of oxidative stress • in tissues of mussels • The biomarkers of SOD, CAT & LPO are suitable • for appraising the seawater quality • and can be used as cost effective test system • for Environmental Risk Assessment

  18. Health condition Sex Age Nutritional status Metabolic activities Migratory behavior Reproductive & Developmental status Population density Biomarker Responses Season Ambient temperature Heterogeneity of the Environmental Pollution Factors that affect biomarker responsesof oxidative stress in aquatic organisms

  19. Thank you for your attention Danke Ihnen für Ihre Aufmerksamkeit

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