1. Understanding how our Water gets Polluted You will be able to understand how and why chemicals create problems in our water supply You will be able to understand how and why chemicals create problems in our water supply You will understand the benefits and risks of using chemicals You will understand the benefits and risks of using chemicals

2. Thinking Questions? Do you think all poisons to kill pests should be restricted? Do you think all poisons to kill pests should be restricted? What happens when a chemical is over used? What “CHANGES” occur? What happens when a chemical is over used? What “CHANGES” occur? Why would NC allow pig farms to have sewer ponds knowing the potential risk they are to the environment? Why would NC allow pig farms to have sewer ponds knowing the potential risk they are to the environment? What are the benefits/risks to using chemicals? What are the benefits/risks to using chemicals? What CHANGES can you make in your daily habits to reduce your exposure to chemicals? What CHANGES can you make in your daily habits to reduce your exposure to chemicals?

5. 4 types of Water pollution Toxins (poisons)

6. 4 Types of Water pollution Sediment (Turbidity)

7. 4 Types of Water Pollution Nutrients (fertilizers/waste)

8. 4 Types of Water Pollution Bacterial (improper waste removal)

9. 5 Main Effects of any Chemical Usage Dose- amount of chemical initially sprayed or release to environment Dose- amount of chemical initially sprayed or release to environment Potency- amount of chemical needed to perform desired action (lab tests determine this) Potency- amount of chemical needed to perform desired action (lab tests determine this) Exposure Time- how long chemical lasts or stays “Active”; most chemicals now designed to biodegrade or break down over time Exposure Time- how long chemical lasts or stays “Active”; most chemicals now designed to biodegrade or break down over time Individual Susceptibility- how each organisms responds to chemical; determined by genetics Individual Susceptibility- how each organisms responds to chemical; determined by genetics Concentration- How chemical levels vary throughout usage and food chain of ecosystem; creates biomagnification issues Concentration- How chemical levels vary throughout usage and food chain of ecosystem; creates biomagnification issues

10. DDT: Why was DDT used?

11. DDT Spraying: Why use DDT? EVENT Spraying of DDT Effects: DOSE Spread over Wide Area Highly Effective Unknown amount Used Effects: Potency Never tested to Determine amount Needed to kill Single organism TO MUCH USED Effects: Exposure Time DDT never tested To determine bio- Degradability DDT FAILS TO BREAKDOWN STAYS ACTIVE Effects: Individual Susceptibility Individual organisms Have different tolerance To chemical MORE CHEM. NEEDED TO BE STILL EFFECTIVE Effects: Concentration: DDT levels at first small Level gets higher In food chain BIOMAGNIFICATION GREATLY INCREASES DDT CONCENTRATION Cause: To prevent mosquito borne diseases PREVENT DEATHS Cause: To Prevent Crop loss from insects HIGH CROP YIELD MORE PROFIT

12. What is Biomagnification?

13. Reaction to Polluted Waters