| Chlorofluorocarbons | (Environmental Engineering) Synthetic organic compounds used for refrigerants, aerosol propellants (prohibited in the U.S.), and blowing agents in plastic foams. CFCs migrate to the upper atmosphere destroying ozone and increasing global warming. Typical atmospheric residence times are 50 to 200 years. |
| Decomposers | (Environmental Engineering) Organisms which utilize energy from wastes or dead organisms. Decomposers complete the cycle by returning nutrients to the soil or water and carbon dioxide to the air or water. |
| Ethers | (Environmental Engineering) An organic compound which has two hydrocarbon groups bound by an interior oxygen atom. The general formula is R'-O-R". |
| Eucaryotic organisms | (Environmental Engineering) Organisms which possess a nuclear membrane. This includes all known organisms except viruses and bacteria. |
| Greenhouse gases | (Environmental Engineering) Gases which trap solar radiation. Of the solar energy entering the earth's atmosphere a portion is reflected back and a portion penetrates onto the earth's surface. The portion reflected back from the earth's surface is at a different wavelength that when it entered. Carbon dioxide and other gases, which pass solar radiation, absorb this reflected radiation, increasing the earth's temperature. This is much like a greenhouse, hence the name. |
| Heterotrophic | (Environmental Engineering) A group of organisms which obtain carbon for synthesis from other organic matter or proteins. |
| Hydrocarbon | (Environmental Engineering) Any organic compound composed entirely of carbon and hydrogen. Two examples are methane gas and octane. |
| Ketones | (Environmental Engineering) Organic compounds with two hydrocarbon groups bonded to a carbonyl group. |
| Organic compound | (Environmental Engineering) Any compound containing carbon except for the carbonates (carbon dioxide, the carbonates and bicarbonates), the cyanides, and cyanates. |
| Photoautotrophic | (Environmental Engineering) Organisms which utilize inorganic carbon dioxide for protoplasm synthesis and light for an energy source. See autotrophic and chemoautotrophic. |