Chapter 19 Air Pollution

Atmospheric pressure (millibars) Altitude (kilometers) The Atmosphere Fig. 19.2 Pressure = 1,000 millibars at ground level Atmospheric pressure (millibars) 200 400 600 800 1,000 120 110 100 90 80 70 60 50 40 30 20 10 (Sea Level) –80 –40 Temperature (˚C) Altitude (kilometers) Altitude (miles) 75 65 55 45 35 25 15 5 Thermosphere Heating via ozone Mesosphere Stratosphere Ozone “layer” Heating from the earth Troposphere Temperature Pressure Mesopause Stratopause Tropopause 78% N, 21% O Ozone layer Greenhouse effect Separation of layers due to differences in temperature and variations in absorption of solar energy Most of our weather in the troposphere

AIR POLLUTION Some primary air pollutants may react with one another or with other chemicals in the air to form secondary air pollutants. Figure 19-3

Major Air Pollutants Suspended particulate matter (SPM): Consists of a variety of solid particles and liquid droplets small and light enough to remain suspended in the air. The most harmful forms of SPM are fine particles (PM-10, with an average diameter < 10 micrometers) and ultrafine particles (PM-2.5). According to the EPA, SPM is responsible for about 60,000 premature deaths a year in the U.S.

Major Air Pollutants Ozone (O3): Is a highly reactive gas that is a major component of photochemical smog. It can Cause and aggravate respiratory illness. Can aggravate heart disease. Damage plants, rubber in tires, fabrics, and paints.

Temperature Inversions Cold, cloudy weather in a valley surrounded by mountains can trap air pollutants (left). Areas with sunny climate, light winds, mountains on three sides and an ocean on the other (right) are susceptible to inversions. Figure 19-5

Acid Deposition and Humans Respiratory diseases Toxic metal leaching Decreased visibility Damage to structures, especially containing limestone Wet acid- acid rain reacting with water vapor in atmosphere; dry acid rain- particles that fall on the soil.—Together acid deposition Decreased productivity of fisheries, forests, and farms

ACID DEPOSITION Acid deposition consists of rain, snow, dust, or gas with a pH lower than 5.6. Figure 19-6

Acid Deposition and Aquatic Systems Water boatman Whirligig Yellow perch Lake trout Brown trout Salamander (embryonic) Mayfly Smallmouth bass Mussel 6.5 6.0 5.5 5.0 4.5 4.0 3.5 pH Fish declines Undesirable species Acid shock pH affects lake system and species can only tolerate so much pollution. Can kill fish or inhibit reproduction. Norway, Sweden 16,000 lakes have no fish; Canada 14,000 lakes acidic, Here in US 9000 lakes.

Acid Deposition, Plants, and Soil Nutrient leaching Heavy metal release Weakens trees Fig. 19-9

Acid Deposition in the US Natural value is 5.6 Sulfur emission from coal plants in the east West coast is emission of NO from motor vehicles. Fig. 19-7

Tobacco Smoke Carbon Monoxide Methylene Chloride Para-dichlorobenzene Chloroform Tetrachloroethylene Formaldehyde 1, 1, 1- Trichloroethane Styrene Nitrogen Oxides Benzo-a-pyrene Particulates According to EPA studies in the U.S. levels of 11 common pollutants are generally 2-5 times higher inside homes and commercial buildings than outdoors. Up to 70X in some cases. 18X higher if you are stuck in a car in traffic. Sick building syndrome--20% of people suffer from persistent symptoms (headache, sneezing....) that disappear when they go outside. Estimated that 17% of buildings have sick building syndrome. More prevalent in newer buildings because there is less air exchange within the building to save energy costs. Ø Primary culprits of sick building syndrome are mineral fibers falling from ceiling tiles. Tobacco Smoke Radon-222 Asbestos Carbon Monoxide Methylene Chloride Fig. 19-11, p. 453

INDOOR AIR POLLUTION Indoor air pollution usually is a greater threat to human health than outdoor air pollution. According to the EPA, the four most dangerous indoor air pollutants in developed countries are: Tobacco smoke. Formaldehyde. Radioactive radon-222 gas. Very small fine and ultrafine particles.

Air Pollution is a Big Killer Each year, air pollution prematurely kills about 3 million people, mostly from indoor air pollution in developing countries. In the U.S., the EPA estimates that annual deaths related to indoor and outdoor air pollution range from 150,000 to 350,000. According to the EPA, each year more than 125,000 Americans get cancer from breathing diesel fumes.

Air Pollution is a Big Killer Spatial distribution of premature deaths from air pollution in the United States. Figure 19-16

Case Study: Radioactive Radon Radon-222, a radioactive gas found in some soils and rocks, can seep into some houses and increase the risk of lung cancer. Sources and paths of entry for indoor radon-222 gas. Figure 19-13

Solutions: Preventing and Reducing Air Pollution Clean Air Act National Ambient Air Quality Standards (NAAQS) Clean Air Acts---1970, 1977, 1990--National Ambient Air Quality Standards. Regulates maximum allowable level in the outdoor air over a specific period of time.Determined by risk assessment. 100 different toxic pollutants. Primary- related to health and secondary environmental and property damage Estimated the clean has reduced 98% reduction in lead( gas banned), 93%VOC, 88% Suspended particulate matter, 44% sulfur dioxide, 26% carbon monoxide. 6.8 trillion in saving with 436 million spent. 20 years prevented 1.6 million premature deaths and 300 million cases of respiratory disease Can test air just like water for violations --collect air in canisters or tedlar bags. Primary and secondary standards Emission Trading Policy

Using the Marketplace to Reduce Outdoor Air Pollution To help reduce SO2 emissions, the Clean Air Act authorized and emission trading (cap-and-trade) program. Enables the 110 most polluting power plants to buy and sell SO2 pollution rights. Between 1990-2002, the emission trading system reduced emissions. In 2002, the EPA reported the cap-and-trade system produced less emission reductions than were projected.

PREVENTING AND REDUCING AIR POLLUTION Environmental scientists point out several deficiencies in the Clean Air Act: The U.S. Congress has failed to increase fuel-efficiency standards for automobiles. Regulation of emissions from motorcycles and two-cycle engines remains inadequate. There is little or no regulation of air pollution from oceangoing ships in American ports.

Solutions: Reducing Outdoor Air Pollution There are a of ways to prevent and control air pollution from motor vehicles. Because of the Clean Air Act, a new car today in the U.S. emits 75% less pollution than did pre-1970 cars. There is and increase in motor vehicle use in developing countries and many have no pollution control devices and burn leaded gasoline.

• Do not buy furniture and other products containing formaldehyde. What Can You Do? Indoor Air Pollution • Test for radon and formaldehyde inside your home and take corrective measures as needed. • Do not buy furniture and other products containing formaldehyde. • Remove your shoes before entering your house to reduce inputs of dust, lead, and pesticides. • Test your house or workplace for asbestos fiber levels and for any crumbling asbestos materials if it was built before 1980. • Don't live in a pre-1980 house without having its indoor air tested for asbestos and lead. • Do not store gasoline, solvents, or other volatile hazardous chemicals inside a home or attached garage. Figure 19.21 Individuals matter: ways to reduce your exposure to indoor air pollution. QUESTION: Which three of these actions do you think are the most important? • If you smoke, do it outside or in a closed room vented to the outside. • Make sure that wood-burning stoves, fireplaces, and kerosene- and gas-burning heaters are properly installed, vented, and maintained. • Install carbon monoxide detectors in all sleeping areas. Fig. 19-21, p. 461

Emissions of sulfur dioxide down 49% since 1970. LA 1976-1990 average 150 days in violation in 2004 is was 27 days. End chapter 19