Helpful Notes Environmental

7.1 Introduction to Air Pollution Pollutants released from burning fossil fuels - carbon dioxide, sulfur dioxide, toxic metals, and particulates. Ozone as an air pollutant - Ozone causes formation of photochemical smog, and converts to nitric acid in the atmosphere, causing acid rain. Particulate matter - a complex mixture of extremely small particles and liquid droplets. Clean Air Act - regulated the use of lead, particularly in fuels, which dramatically decreased the amount of lead in the atmosphere. Environmental Protection Agency - responsible for the protection of human health and the environment and it provides technical assistance to support recovery planning of public health and infrastructure, such as waste water treatment plants. Primary pollutants - an air pollutant emitted directly from a source (carbon dioxide) Secondary pollutants - not directly emitted as such, but forms when other pollutants react in the atmosphere. (smog) 7.2 Photochemical Smog Formula for photochemical smog - is formed when nitrogen oxides and volatile organic hydrocarbons react with heat and sunlight to produce a variety of pollutants. When is ozone at its highest concentration? - peak in the afternoon and are higher in the summer because ozone is produced by chemical reactions between oxygen and sunlight. Volatile Organic Compounds - formaldehyde and gasoline, evaporate or sublimate at room temperature. Trees are a natural source of VOCs. What conditions are ideal for the formation of photochemical smog? forms in urban areas because of the large number of motor vehicles there. How can photochemical smog be reduced? Through the reduction of nitrogen oxide and VOCs. How is photochemical smog harmful to human health? causes respiratory problems and eye irritation. 7.3 Thermal Inversion Thermal inversion - During a thermal inversion, the normal temperature gradient in the atmosphere is altered as the air temperature at the Earth’s surface is cooler than the air at higher altitudes. It traps pollution close to the ground, especially smog and particulates. 7.4 Atmospheric CO2 And Particulates Describe natural sources of CO2 and particulates.- respiration, decomposition, and volcanic eruptions. 7.5 Indoor Air Pollutants Carbon monoxide - indoor air pollutant that is classified as an asphyxiant. Asphyxiant Three examples of particulate indoor air pollution. - Secondhand Smoke, Environmental Tobacco Smoke, Stoves and Heaters Three sources of indoor air pollutants. Pressed Wood Products, Lead, Nitrogen Dioxide Three natural sources of indoor air pollutants. - radon, mold, and dust. Where are VOCs found indoors? - from furniture, paneling and carpets; formaldehyde from building materials, furniture, upholstery, and carpeting; and lead from paints. What indoor items contain formaldehyde? Name six common combustion air pollutants.- carbon monoxide, nitrogen oxides, sulfur dioxide, particulates, and tobacco smoke. Radon-222, where does it come from, and what does it cause? a naturally occurring radioactive gas that is produced by the decay of uranium found in some rocks and soils. 7.6 Reduction of Air Pollutants Name three categories to reduce air pollution. - regulatory practices, conservation practices, and alternative fuels Vapor recovery nozzle - air pollution control device on a gasoline pump that prevents fumes from escaping into the atmosphere when fueling a motor vehicle. Catalytic converter - an air pollution control device for internal combustion engines that converts pollutants in exhaust into less harmful molecules Wet and dry scrubbers - air pollution control devices that remove particulates and/or gases from industrial exhaust streams. Electrostatic precipitator - a filterless device that removes fine particles, like dust and smoke, from a flowing gas using the force of an induced electrostatic charge minimally impeding the flow of gases through the unit. 7.7 Acid Rain Acid deposition - due to nitrogen oxides and sulfur oxides from anthropogenic and natural sources in the atmosphere. NOx - a group of highly reactive gases. It is generally caused by sulfur dioxides and nitrogen oxides which react with water in the atmosphere. SOx - sulfur containing coal burned in power plants, oil refining Environmental effects of acid deposition on the environment - affects communities that are downwind from coal-burning power Plants. It can lead to the acidification of soils and bodies of water and corrosion of human-made structures. 7.8 Noise Pollution Noise pollution, sources, and effects - sound at levels high enough to cause physiological stress and hearing loss. Sources of noise pollution in urban areas include transportation, construction, and domestic and industrial activity. Effects of noise pollution on animals in ecological systems include stress, the masking of sounds used to communicate or hunt, damaged hearing, and causing changes to migratory routes.