water pollution

4. bloom occurs when toxin-producing algae grow excessively in a body of water
7. the action of making a liquid more dilute.
9. process that improves the quality of water to make it appropriate for a specific
10. any substance that has a defined composition.
13. poisonous.
14. the action of stopping something from happening or arising.
15. water that has been used in the home, in a business, or as part of an industrial process.

1. a synthetic material made from a wide range of organic polymers
2. harmful substance that sometimes spills onto water ways leaving a thick screen over the water
3. the introduction of harmful materials into the environment
5. A large group of single-cell microorganisms
6. water held underground in the soil or in pores and crevices in rock.
8. the process of adding chlorine to drinking water to kill parasites, bacteria, and viruses.
11. matter that settles to the bottom of a liquid; dregs.
12. a body of rock and/or sediment that holds groundwater.