Chapter 12

 Air Pollution – any harmful substance put into the air ◦ Can come from human sources or natural sources ◦ Natural sources include volcanoes, forest fires, burping lakes

 Primary pollutant – pollutant put into the air directly by human activity  Secondary pollutant – forms when primary pollutants react with other primary pollutants or with naturally occurring substances (ex. Acid rain)

 Most air pollution produced by humans comes from transportation and industry.  Transportation – almost 1/3 of air pollution comes from burning gasoline in motor vehicles  Industry – many industries burn fossil fuels to produce energy

 Passed in 1970, amended in 1990 ◦ Gives the Environmental Protection Agency (EPA) the authority to regulate motor vehicle emissions  California has the strictest laws 1) removed lead from gasoline 2) Mandated the use of the catalytic converter (p. 328 Figure 3)

 The Clean Air Act requires industries to use pollution control devices ◦ Ex: Scrubbers and electrostatic precipitators ◦ Scrubbers work by spraying gases with water, which removes many pollutants (page 329 Figure 5)

 Smog – when air pollution hangs over urban areas and reduces visibility (p. 330 Figure 6)  Temperature inversion – when a layer of cold air is trapped by a layer of warm air. This traps air pollutants and is more likely to occur in a valley (p. 330 Figure 7)

 Make sure that you copy the “Primary Pollutants” Chart from p. 326 into your notes!

Effects of Air Pollution Short Term – occurs when symptoms come on quickly and usually go away within a few hours or days

 Headache  Nausea  Dizziness  Irritation of eyes, nose, and throat  Coughing  Tightness in the chest  Upper respiratory infection

 Long Term – these symptoms occur after being exposed to air pollution for a long period of time (Chronic exposure) ◦ These symptoms DO NOT EVER go away. Examples of Long Term Effects Emphysema Lung Cancer Heart Disease

 Indoor Air Pollution – when the quality of air inside a building is worse than the air outside ◦ Because people spend more time inside than outside, indoor air pollution affects human health more than outdoor air pollution ◦ This is more of a problem in buildings that are tightly sealed and well-insulated

 New paint  Building materials  New carpets  Certain types of furniture – (pressed wood) “ready-to-assemble” furniture  Tobacco smoke  Cleaning materials  Gasoline  Carbon monoxide  Radon (radioactive gas given off by granite)

 If a building has very poor air quality and contains 1 or more of these pollutants, people who spend time in the building can develop a condition called “sick-building syndrome”  In order to have sick-building syndrome, your symptoms must go away when you leave the building and return the next time you enter it.

 How to stop indoor air pollution: 1.Identify and remove the source 2. Add ventilation to the building

 Asbestos – is several minerals that form long, thin fibers which are very strong and fire resistant ◦ Asbestos was used in many building materials ◦ If the asbestos fibers break off and become airborne (friable), they can be inhaled and damage the lungs

3 Major Diseases Caused by Asbestos 1. Asbestosis – asbestos fibers in the lungs 2. Mesothelioma – cancer of the chest lining 3. Lung cancer

 Radon – colorless, odorless gas that seeps into homes through cracks in the foundation or basement ◦ Radon is radioactive ◦ Radon is the second leading cause of lung cancer ◦ If the radon levels are high, you must: 1.Seal the cracks and holes in basement/foundation 2.Install ventilation systems

 Noise pollution – any loud, unwanted sound ◦ Can cause damage to hearing and actually destroys cells in your ears ◦ Sound at 120 decibels is at the threshold of pain  See table 2 on page 334

 Light pollution – blocks our view of the night time sky ◦ Does not present a direct hazard to human health ◦ More important environmental concern is energy waste

 Acid precipitation – rain, snow, sleet, or hail that contains a high concentration of acids ◦ Caused by the burning of fossil fuels which releases nitrogen oxides and sulfur oxides ◦ These chemicals mix with water from the atmosphere and form nitric and sulfuric acid  Acid precipitation has a pH of less than 5.0

 3 major areas: 1) causes a drop in the pH of soil and water acidification  This causes nutrients to get dissolved and washed away  Causes aluminum and other toxic metals to be released  It can clog the openings on the surface of plants

2) It can kill fish and other aquatic animals Acid shock – sudden influx of acidic water that occurs when acid snow melts 3) Effects on humans: Can cause toxic metals to be released into the environment Can cause respiratory problems in children Dissolves the calcium carbonate in many building materials

 Major problem – pollutants released in one area may fall to the ground hundreds or thousands of miles away  Canada-US Air Quality Agreement (1991) ◦ Both countries agreed to lower their use of chemicals that cause acid precipitation