Presentation on theme: "Pollution issues in the Great Lakes Toxic chemicals Nutrients Debris Biological pollution Algae PO 4 Poison With ideas from teachers: Jessie Kubuske, Elaine."— Presentation transcript:
Pollution issues in the Great Lakes Toxic chemicals Nutrients Debris Biological pollution Algae PO 4 Poison With ideas from teachers: Jessie Kubuske, Elaine Frock, Mary Harris, Eli Lowrey
Types of toxic substances sometimes found in the Great Lakes Industrial chemicals: PCBs, dioxins, others PAHs (polycyclic aromatic hydrocarbons): oil and combustion by-products Agricultural chemicals: DDT, Toxaphene, other pesticides and herbicides Heavy metals such as mercury, lead, cadmium
How do toxins impact living things? Bioaccumulation A growing organism ingests more toxin, which is not eliminated because the toxin is dissolved in fat. The older the fish, the more toxin may have accumulated. Fatty fish are worst. Biomagnification Accumulated toxins are magnified as they pass through the food chain. Those higher on the chain collect the toxins accumulated by those they eat, and so on down.
Where do people fit in a contaminated food chain? Phytoplankton.0003 mg PCBs /kg Herring gull eggs 47 mg PCBs /kg Walleye 2.0 mg PCBs /kg Smelt.32 mg PCBs /kg Gammarus.01 mg PCBs /kg HUMAN ?
Nutrients can be pollutants too! Main sources –fertilizer runoff –sewage without proper treatment Types of nutrients –Phosphates –Nitrates Effects –Dissolved oxygen depleted –Eutrophication accelerated
Debris Pollution [Solid materials discarded on shore, in inland areas, and from boats] Problems: –Creates hazards for wildlife and humans –Fouls recreational areas Solutions: –Short-term: Coastweeks “beach sweeps” clean up shorelines worldwide! –Long-term: Change “throwaway society”
Biological pollution Bacterial contamination Introduced species
Who is responsible for the health of the Great Lakes? Governments –8 states –1 province –100s of local units –U.S., Canada, First Nations tribes International Joint Commission Business, industry, and individuals