SasAqS Powerpoint Presentation

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This is my Presentation from the South African Society for Aquatic Scientists that I presented in June 2010

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  • 1. and drains an area of nearly 8000 km2 2.was built in 1972 in a gorge in the Lebombo mountains 3. and possesses a 89m high wall.  4. In 1874 this area was proclaimed the Pongola Game Reserve
  • 1. and flows southeast for approximately 600km and terminates in the vast floodplane of the Okavango delta, in northwest Botswana
  • Al Acid environments solubilizes large amounts of aluminium Aluminium toxicity to fish is dependent on the aluminium species and concentration, length of exposure and previous acclimation of the fish. Aluminium related mortalities are usually associated with the production of mucus that clogs the gills, resulting in anoxia and a rapid loss of sodium due to impaired ion-exchange across the gill membrane. This is usually fatal, as it results in the dilution of the blood plasma ions, which leads to severe osmotic problems in tissues and interstitial fluids Accumulation of elevated concentrations of aluminium as a result of the consumption of fish is unlikely, since most of the aluminium in fish is deposited in the liver and gills. Target water quality guidelines pH greater than 6.5: 0.1ug/L, pH less than 6.5 0.5 ug/L As Enters aquatic systems in dissolved form through industrial discharges Metallurgical industry, glass and ceramic industry, pesticide manufacturing, and petroleum refining industries arsenic can be bio-accumulated, it needs to be monitored in the aquatic environment. arsenic interacts with many elements, among them selenium and iodine Most arsenic in water is precipitated on the surface of the body and gills of fish, and causes the production of mucous film, and death is usually attributable to suffocation. High concentrations of arsenic cause direct gill damage, which leads to anoxia and collapse of blood vessels. Some arsenical compounds are fat-soluble and therefore accumulate in fatty tissues, The TWQR for arsenic for water bodies containing fish is 0 - 0.05 mg/R. Cd The most toxic metal pollutant Cladding industry, nuclear reactors, alkaline cells and alloy industry Cadmium has low solubility under conditions of neutral or alkaline pH and is highly soluble under acidic conditions, Cadmium interacts strongly with zinc due to the chemical similarity of the two metals. In aqueous solution reduction cannot occur in water containing dissolved oxygen. Cadmium also interacts with selenium . The following factors influence the lethal concentration of cadmium. ! Temperature : cadmium toxicity is increased at high water temperatures; ! The dissolved oxygen concentration : survival decreases in water containing low dissolved oxygen concentrations; ! pH : high pH increases bioaccumulation of cadmium; ! Water hardness : a negative relationship exits between the logarithm of cadmium toxicity and the logarithm of water hardness. Increased hardness reduces bioaccumulation and toxicity of cadmium to fishes; ! Additive (synergistic) effects with other metals : additive toxicities have been found for the following combinations of metals: copper and cadmium; and cadmium and mercury ; and ! Infra-additive effects with other metals : cadmium toxicity is lowered in the presence of sublethal concentrations of zinc . There is no difference in the toxicity of cadmium in water with or without suspended solids. Cadmium may be removed from solution by adsorption. Cadmium is adsorbed on humicmaterials to a far greater extent than onto clay or silica particles Gill tissue is initially damaged by detachment of the epithelial layer with consequent hypertrophy and hyperplasia of the interlamellar epithelium. 0.15-0.4ug/L depending on water hardness Cobalt AGRICULTURE Livestock Watering Irrigation Aquaculture 0 - 1 0 - 0.05 NA mg/L Cobalt is not generally considered a plant nutrient, but appears to be essential for some plant species. Cobalt concentrations in the range of 0.1 - 5 mg/R have been found to be toxic to a variety of food crops when added to nutrient solutions. The occurrence of cobalt toxicity is rare under field conditions, presumably because it is strongly sorbed by soil. Generally cobalt does not accumulate in edible parts of plants to levels that are dangerous to consumers Elevated cobalt levels may occur in the vicinity of mines where the ores that are processed contain cobalt. Cobalt is stored in the liver, kidneys, adrenal glands and bones and is poorly retained in body tissues. Excess cobalt is rapidly excreted, primarily as urine, although cobalt is secreted in the bile and hence reabsorption is possible.
  • SasAqS Powerpoint Presentation

    1. 1. METAL AND DDT BIOACCUMULATION AND BIOMARKER RESPONSES OF THE TIGERFISH, HYDROCYNUS VITTATUS , FROM THE JOZINI DAM AND OKAVANGO RIVER. <ul><li>Miss E. Fisher, Miss Liesel Whitlow, Prof. V. Wepener & Prof. N. Smit </li></ul>
    2. 2. INTRODUCTION <ul><ul><li>Why tigerfish? </li></ul></ul><ul><ul><ul><li>High trophic level (Skelton 2001) </li></ul></ul></ul><ul><ul><ul><li>Robbers, minnows, sardines (Skelton 2001) </li></ul></ul></ul><ul><ul><ul><li>Bioaccumulate and biomagnify (Mhlanga 2000) </li></ul></ul></ul><ul><ul><ul><li>Increasing human activity. </li></ul></ul></ul><ul><ul><ul><li>Little known about bioaccumulation and biomarker responses in tigerfish (Mhlanga 2000; du Preez & Steyn 1991), biomarkers (Whitlow et al . 2008) </li></ul></ul></ul>
    3. 3. AIM: <ul><li>To compare bioaccumulation of heavy metals and DDT in tigerfish from two systems of varying impacts. </li></ul><ul><li>To relate biomarker responses of tigerfish from these systems, and determine whether or not tigerfish are being stressed as a result of exposure. </li></ul>
    4. 4. HYPOTHESIS <ul><li>Part 1: </li></ul><ul><li>Tigerfish from the Jozini Dam will have higher levels of heavy metals and DDT than tigerfish from the Okavango River. </li></ul><ul><li>Part 2 </li></ul><ul><li>Tigerfish from the Jozini Dam will exhibit more stress than tigerfish from the Okavango River as a result of the greater influx of pollutants into this system. </li></ul>
    5. 5. STUDY OBJECTIVES <ul><li>To determine the environmental partitioning of heavy metals in the Jozini Dam and Okavango River. </li></ul><ul><li>To compare the concentrations of heavy metals and DDT in the muscle tissue of tigerfish from these ecosystems. </li></ul><ul><li>To compare biomarker responses between tigerfish from the different sites, and </li></ul><ul><li>to relate the biomarker responses to the metal and DDT bioaccumulation in the muscle tissue of tigerfish. </li></ul>
    6. 6. SITE SELECTION <ul><li>tigerfish presence (Skelton 2001) </li></ul><ul><li>varying degrees of impacts </li></ul><ul><li>Jozini Dam: slightly impacted </li></ul><ul><li>Okavango River: relatively unimpacted </li></ul>
    7. 7. JOZINI DAM Photos taken from DWAF(2004)
    8. 8. JOZINI DAM <ul><li>The Phongolo river: east of Wakkerstroom </li></ul><ul><li>Jozini dam wall (1972). </li></ul><ul><li>2492 million m 3 water. </li></ul><ul><li>DDT sprayings </li></ul><ul><li>Current uses (DWAF 2004). </li></ul><ul><li>Jozini Dam: Tigerfish </li></ul>
    9. 9. OKAVANGO RIVER
    10. 10. OKAVANGO RIVER <ul><li>The Okavango river (McCarthny 2005; Wilk et al . 2006) </li></ul><ul><ul><ul><li>10km 3 + 6km 3 per annum </li></ul></ul></ul><ul><ul><ul><li>25000km 2 permanent </li></ul></ul></ul><ul><ul><ul><li>80000km 2 seasonal </li></ul></ul></ul><ul><ul><ul><li>170 000 tonnes </li></ul></ul></ul><ul><ul><ul><li>360 000 tonnes </li></ul></ul></ul><ul><li>Threats: </li></ul><ul><ul><ul><li>Boro River (Ellery & McCarthy 1998) </li></ul></ul></ul><ul><ul><ul><li>Potential development </li></ul></ul></ul>http:// wpcontent.answers.com/wikipedia/commons/thumb/7/72/Okavango_RiverSign.jpg/288px-Okavango_River_Sign.jpg http://www.cfnews13.com/uploadedImages/Site_Content/Features/Kissimmee_River/Rest1.jpg <ul><ul><ul><li>http://www.geog.ucl.ac.uk:8080/print-version/about-the-department/people/academics/martin-todd/accord/images/map2.jpg </li></ul></ul></ul>
    11. 11. METHOD <ul><li>SAMPLING </li></ul><ul><ul><li>Sediment & water </li></ul></ul><ul><ul><ul><li>Acid washed polypropylene bottles </li></ul></ul></ul><ul><ul><li>Tigerfish </li></ul></ul><ul><ul><ul><li>Caught </li></ul></ul></ul><ul><ul><ul><li>Anesthetized & Sacrificed </li></ul></ul></ul><ul><ul><ul><li>Dissected </li></ul></ul></ul><ul><ul><ul><li>Muscle frozen </li></ul></ul></ul><ul><ul><ul><li>Biomarkers: </li></ul></ul></ul><ul><ul><ul><ul><li>Hendrickson stabilization buffer </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Liquid nitrogen </li></ul></ul></ul></ul>University of Johannesburg Zoology Department
    12. 12. CONT. OF METHOD <ul><li>PROCESSING </li></ul><ul><ul><ul><li>Metals </li></ul></ul></ul><ul><ul><ul><ul><li>Dried </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Digestion </li></ul></ul></ul></ul><ul><ul><ul><ul><li>ICP-MS </li></ul></ul></ul></ul><ul><ul><ul><ul><li>ICP-OES </li></ul></ul></ul></ul><ul><ul><ul><li>Pesticides </li></ul></ul></ul><ul><ul><ul><ul><li>Freeze dried </li></ul></ul></ul></ul><ul><ul><ul><ul><li>GCMS ( μ g/g lipid) </li></ul></ul></ul></ul><ul><li>Biomarkers </li></ul><ul><ul><li>AChE (Ellman et al . 1961) </li></ul></ul><ul><ul><li>LP (MDA) (Ohkawa et al . 1979; Uner et al . 2005) </li></ul></ul><ul><ul><li>CAT (Cohen et al . 1970) </li></ul></ul>http://www.wcaslab.com/images/icpms/plasma.jpg
    13. 13. CONT. OF METHOD <ul><ul><li>PC (Parvez & Raisuddin 2005; Levine et al . 1990; Fernandes et al . 2008; Floor & Wetzel 1998) </li></ul></ul><ul><ul><li>Metallothioneins (Viarengo et al . 1997; Viarengo et al . 1999; Atli & Canli 2008; Fernandes et al . 2008; Hubbard 2005) </li></ul></ul><ul><ul><li>CEA (de Coen & Janssen 1997; de Coen & Janssen 2003) </li></ul></ul><ul><li>STATISTICAL ANALYSIS </li></ul><ul><ul><ul><li>Unpaired Student t-Test </li></ul></ul></ul><ul><ul><ul><li>PASW(18.0) </li></ul></ul></ul><ul><ul><ul><li>Significance P <0.05 </li></ul></ul></ul>
    14. 14. RESULTS AND DISCUSSION SEDIMENT AND WATER COMPARISON (Huntsman_Mapila et al . 2005; Huntsman Mapila et al . 2009)
    15. 15. RESULTS & DISCUSSION METALS: MUSCLE Jozini Jozini Jozini Jozini Jozini
    16. 16. RESULTS & DISCUSSION METALS:MUSCLE <ul><li>Coal mining and shales: Cu, Fe (Johnson et al . 2006; Huntsman Mapila et al . 2009) </li></ul>Jozini Jozini Jozini
    17. 17. RESULTS & DISCUSSION METALS: MUSCLE (Sawula 2004) Jozini Jozini Jozini
    18. 18. DDT EXPOSURE Jozini
    19. 19. RESULTS & DISCUSSION BIOMARKERS <ul><li>BIOMARKERS OF OXIDATIVE STRESS </li></ul>Jozini Jozini Jozini
    20. 20. RESULTS & DISCUSSION PARAMETERS OF CEA Jozini Jozini Jozini
    21. 21. RESULTS & DISCUSSION Cont. of CEA Parameters Jozini Jozini Jozini Okavango
    22. 22. RESULTS & DISCUSSION Biomarkers of effect Jozini Jozini
    23. 23. CONCLUSION <ul><li>HAVE WE ACCEPTED PART 1 OF OUR HYPOTHESIS? </li></ul><ul><li>YES! </li></ul><ul><li>Tigerfish from the Jozini Dam are bioaccumulating higher levels of pollutants, than tigerfish from the Okavango River. </li></ul>
    24. 24. CONCLUSION <ul><li>HAVE WE ACCEPTED PART 2 OF OUR HYPOTHESIS? </li></ul><ul><li>NO! </li></ul><ul><li>Tigerfish from the Jozini Dam are experiencing less oxidative stress than tigerfish from the Okavango River, however they have greater responses to exposure of toxicants. </li></ul>
    25. 25. POSSIBLE REASONS FOR STRESS <ul><li>Okavango oxidative stress & lower CEA: </li></ul><ul><ul><ul><li>Barbel run </li></ul></ul></ul><ul><ul><ul><li>Lotic environment </li></ul></ul></ul><ul><li>Jozini AChE & MT </li></ul><ul><ul><ul><li>AChE: Carbamate pesticides, organophosphates, nerve gases </li></ul></ul></ul><ul><ul><ul><li>MT: Higher levels of metals: Cu & Cd </li></ul></ul></ul>
    26. 26. EXTRA CONSIDERATIONS <ul><ul><li>NUTRIENTS </li></ul></ul><ul><ul><li>CATIONS </li></ul></ul><ul><ul><li>ANIONS </li></ul></ul><ul><ul><li>PHYSICAL WATER PARAMETERS </li></ul></ul><ul><ul><li>GEOLOGY </li></ul></ul><ul><ul><li>SAMPLING TIME </li></ul></ul>
    27. 27. ACKNOWLEDGEMENTS <ul><li>WATER RESOURCE COMISSION (Resources) </li></ul><ul><li>PROFESSOR V. WEPENER (Supervisor) </li></ul><ul><li>PROFESSOR N. SMIT (Co-supervisor) </li></ul><ul><li>MISS LIESEL WHITLOW (Data from the Okavango) </li></ul><ul><li>DR. H. VAN NIEKERK (SPEC-RAU) </li></ul><ul><li>MISS NATALIE DEGGER (Assistance with SPSS) </li></ul><ul><li>MR. KYLE MCHUGH (Sample Collection & Pictures) </li></ul><ul><li>MISS MICHELLE SOEKOE (Sample Collection) </li></ul><ul><li>MISS YOLANDI CLOETE (Sample Collection & other) </li></ul>
    28. 28. THANK YOU!

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