| A | B |
|---|
| water pollution | chemical, biological, or physical change in water quality that has a harmful effect |
| disease-causing agents (pathogens) | bacteria, viruses, protozoa, parasitic worms |
| coliform bacteria | organisms excreted in human waste, measured to assess drinking or swimming water |
| oxygen demanding wastes | organic wastes that can be decomposed by aerobic bacteria |
| biological oxygen demand (BOD) | amount of dissolved oxygen needed by aerobic decomposers to break down organic materials in a certain volume of water |
| water soluble inorganic chemicals | acids, salts, and toxic metals |
| inorganic plant nutrients | nitrates and phosphates that cause excessive plant growth |
| organic chemicals | oil, gasoline, plastic, pesticides, cleaning solvents, detergents |
| sediment | suspended particles of soil or other solids |
| genetic pollution | from disruption of aquatic system from the introduction of a nonnative species |
| point source | specific place that discharges pollutants such as pipes or sewers |
| nonpoint souce | source that cannot be traced to a single discharge site such as acid deposition |
| eutrophication | nutrient enrichment of a body of water |
| cultural eutrophication | increase in nutrients from urban areas or human activites |
| thermal pollution | large inputs of heated water into a natural body of water |
| thermal shock | effect on living organisms from a sharp change in water temperature |
| thermal enrichment | term used by some to emphasize the benefits of adding heated water to a natural body of water |
| dredge spoils | materials, often scraped from bottoms of rivers and shipping channels |
| sewage sludge | mixture of solids removed from wastewater plant |
| primary sewage treatment | mechanical process that filters out larger debris |
| secondary sewage treatment | biological process used to remove wastes |
| advanced sewage treatment | series of chemical and physical processes that remove specific pollutants |
