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Download Ecotoxicology - Coastal Carolina University
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Ecotoxicology You are what you eat! Where is Pollution? • Most near the coast… • 76% of fish harvested come from the coast Pfiesteria • Found in waters high in nutrients • Pfiesteria is microscopic algae that is a natural part of the environment • Harmful Algal Bloom (HABs) RED TIDE • During intense algal blooms, dangerous levels of toxins are released into the water. These toxins kill fish (millions of fish may die in a red tide) and accumulate in the fatty tissues of shellfish. Humans and other animals that eat contaminated shellfish may become paralyzed or even die. anthropogenic • Human- caused pollutants – Population growth in many urban areas – New materials and new procedures →new and often dangerous chemicals Coliform Bacteria • EPA standards: One coliform colony / 100 mL of water is cause for concern • Four colonies per 100 mL requires direct action • The appearance of coliform bacteria indicates the presence of raw sewage. • Raw sewage may contain disease-producing bacteria. • Coliform is an indicator species. • A coliform test measures the amount of E. coli present in the water supply oil • • • • Exxon Poison to animals Gets into sediments Takes about 10 years to fully clean up • Least damaging pollutant b/c it gets broken down by microorganisms Sewage • Viruses and bacteria if untreated • Boston Harbor treatment project… backed up, raw sewage in drinking water! DDT • Pesticides 1940-1970’s • Dichloro-Diphenyl-Trichloroethane • Breaks down slow… still around TODAY! • Prohibits Ca+ uptake…birds break eggs when they sit on them PCB • Liquid coolant, insulation • Polychlorinated Biphenyls • Liver cancer, genetic mutations, reproductive problems Lead • Paint • Mental retardation Mercury • • • • Batteries, electronics, medical products Does not affect humans (does effect animals) Different forms: elemental, inorganic Bacteria can change Mercury into Methylmercury (bad for us) Methylmercury • • • • • Absorbs easily into tissue Poisonous!!! Eliminated very slowly Concentrated in shells and fingernails Blindness, slurred speech, reproductive failure • Passed from pregnant mom to babyneurological problems • 375,000 babies born each year affected Plant Toxins • Ciguatera Poisoning • Toxin= icthyosarcotoxin • Originates from the blue green algae in the food chain of the fish • Fish known to carry ciguatoxins – Barracuda – Black grouper – King mackerel • Sensory reversal… Bioaccumulation • Bioaccumulation: build-up in concentration of something with each step of the food chain – Crosses the blood/brain barrier and placenta – Eliminated from living tissue very slowly – Is contained in fish flesh and is not reduced or removed by cleaning, trimming or cooking • Bioconcentration: comparison between creature’s concentration and concentration in environment (i.e. seawater)
