AIR Pollutants

1. AIR Pollutants

2. We breathe about 2 gallons of air every minute. • By inhaling polluted air, a typical human lifespan can be reduced by 1-2 years.

3. Air Pollution -Introduction to Air Pollutants (7 min) • https://www.youtube.com/watch?v=UtdKRvWC1yQ -Asian Brown Cloud (2 min) • https://www.youtube.com/watch?v=qYYK-2sDN4U -lots of particulates from cars, coal burning and dust, smoke and ash from drought and the clearing and burning of forests from planting crops -the cloud travels-about 25% of particulates, 77% of black carbon and 33% of toxic mercury in skies above LA can be traced to China.

4. Did You Know….?? • Air pollution caused by human activities, including industrial and energy production, the burning of fossil fuels and increased use of certain types of transport, causes serious health problems for hundreds of thousands of people every year. • Environmental damage such as acidification, eutrophication, tropospheric (ground-level) ozone and reduced air quality, especially in urban areas, can be a local as well as a trans boundary problem as air pollutants are transported in the atmosphere and harm human health and the environment elsewhere.

5. What about air pollution? • What is in air? • How are pollutants classified? • What are the pollutants we are most concerned about? • How do pollutants get in our air? • How can we reduce pollution? • What is indoor pollution? • How can we reduce indoor pollution?

6. What is in Air? Clean air Polluted air Harmful substances can be solids, liquids or gases. Can be brown or grey. Breathing can be difficult • Nitrogen gas • Oxygen gas • Small amounts of argon, CO2 and water vapor • Air is clear • Breathing is easy

7. POLLUTANTS • Can come from natural sources such as volcanoes and dust/pollen from wind • But, most are the result of human activities (anthropogenic).

8. POLLUTANTS • Primary pollutants- a pollutant that is put directly into the air by human activity such as soot from smoke. • Secondary pollutants are formed as a result of a chemical reaction in the air. Examples are: 1. Ozone that is created when emissions from cars react with UV rays from the sun and then stay in the atmosphere. 2. Smog and Acid Rain

9. Particulates video (4min) • http://www.teachersdomain.org/asset/ttv10_vid_aerosols/

10. What Are the Major Outdoor Air Pollutants? 1. Carbon monoxide(CO) 2. Nitrogen oxides (NO) and nitric acid (HNO3) 3. Sulfur dioxide (SO2) and sulfuric acid (H2SO4) 4. Particulate matter - Suspended particulate matter (SPM) 5. VOCs(volatile organic compounds)- organic chemicals that vaporize easily to produce toxic fumes 6. Lead

12. Most air pollution in urban areas comes from motor vehicles and industry.

13. Some natural pollution particulates come from volcanoes, sea spray, and flower pollen

14. Over 1/3 of our air pollution comes from … • CARS! Auto emissions have effects on our air.

15. The main emissions of a car engine are: • Nitrogengas (N2) - Air is 78-percent nitrogen gas, and most of this passes right through the car engine. • Carbon dioxide (CO2) - This is one product of combustion. The carbon in the fuel bonds with the oxygen in the air. • Water vapor (H2O) - This is another product of combustion. The hydrogen in the fuel bonds with the oxygen in the air. • These emissions are mostly harmless, although carbon dioxide emissions are believed to contribute to global warming.

16. Because the combustion process is never perfect, some smaller amounts of more harmful emissions are also produced in car engines. • Catalytic converters are designed to reduce all three: 1. Carbon monoxide (CO) is a poisonous gas that is colorless and odorless. 2. Hydrocarbonsor volatile organic compounds (VOCs) are a major component of smog produced mostly from evaporated, unburned fuel. 3. Nitrogen oxides (NO and NO2, together called NOx) are a contributor to smog and acid rain, which also causes irritation to human mucus membranes.

17. The Catalytic Converter • Works by causing a chemical reaction that turns exhaust emissions into less harmful substances • 2NO → N2 + O2 • 2CO + O2 → 2CO2

18. The Clean Air Act - 1970 • Gave the EPA the authority to regulate automobile emissions. • Required the gradual elimination of lead in gasolineand a decrease in auto emissions • Catalytic converters help reduce auto emissions

19. The Clean Air Act • The effects of the Clean Air Act have been verified with ice cores taken from Greenland. • The ice cores show a dramatic rise in sulfur dioxide in the atmosphere starting around 1900. • Nitrogen oxides begin increasing around 1950. • Levels of both pollutants stabilized after the 1970s.

20. How Can We Reduce Harmful Car Emissions • Drive less • Drive vehicles that use alternative energy sources such as Electric vehicles, hybrids, ethanol …

21. Industrial Air Pollution • Most industries and power plants use fossil fuels for energy. This burning releases large amounts of oxides into the air such as CO2, SO2 and NOx • Manufacturers of electronic products contribute to VOCs from solvents used to clean circuit boards and other parts. • The Clean Air Act requires industries to use scrubbers or other air pollution devices.

22. How do scrubbers work? • Moves gases through a spray of water that dissolves many pollutants. • Electrostatic precipitators – remove particulates by creating an electric charge which attracts these larger particles

23. Thermal Inversions • Thermal inversion occurs when a layer of warm air settles over a layer of cooler air that lies near the ground. • The warm air holds down the cool air and prevents pollutants from rising and scattering. Thermal Inversion Conditions Normal Conditions

24. Air Pollution History • The Donora Fluoride Fog of 1948 • In late October, the town of Donora experienced a temperature inversion. • The town is located along the Monongahela River south of Pittsburgh, within a small valley. • The main employer of the town was a US Steel Zinc smelting plant.

25. Donora Fluoride Fog Noon in Donora • Emissions of sulfur dioxide, nitrogen dioxide, and fluoride from the zinc smelting plant began to accumulate. • The smog became so thick that driving was impossible. • The plant itself did not cease operations until 4 days later. • The smog finally broke up as a rainstorm entered the area after 5 days.

26. THE LONDON SMOG OF 1952 • London naturally has very calm air, and regularly experiences thick sea fog. • The weather turned unusually cold, causing the residents to burn greater amounts of coal to heat their homes. • This combined with a temperature inversion to create a thick smog of sulfur dioxide over the city. • The fog lasted 5 days, and caused between 4,000- 12,000 deaths.

27. SMOG (brown air smog) • When smoke and fog reduce visibility • Smog results from chemical reactions involving sunlight, Nitrogen oxide and hydrocarbons • Automobiles and industries are the main causes • Cities that experience the most smog have dense traffic and are in dry, sunny areas, such as LA, Denver and Mexico City

28. WHAT DO YOU REMEMBER??? • Name the major air pollutants. • What is the difference between primary and secondary pollutants? • Name 2 examples of natural pollution and 2 examples of man made. (anthropogenic) • What are the different sources of industrial pollution and photochemical smog?

29. Air Pollution Effects on Human Health • Chronic Bronchitis and Asthma (worsened) • Emphysema and Lung Cancer • Air pollutants aggravate respiratory diseases. • Heart attacks and strokes • The young and old are most affected. • The London Smog in 1952- 4000 people died in only a few days.

30. Indoor Air Pollution • Many people spend as much as 90% of their days indoors. • Buildings with very poor air quality are said to have sick-building syndrome.

32. Some Important Indoor Air Pollutants

33. Common indoor air pollutants include: • second-hand tobacco smoke; • airborne mold and mildew; • pet dander; • lead-impregnated dust from old paint and some vinyl mini blinds; • cockroach shedding; • Dust mite particles; • combustion gases released by stoves, heaters, candles and fireplaces; and • chemicals released by • dry cleaned clothes; • cleaning products; • room deodorizers; • office supplies; • carpets; • paints and sealers; • new furniture and pressed wood; • personal care products; and • pesticides

34. To reduce the levels of indoor air pollution you can: • never allow smoking indoors; • use less toxic cleaning products; • make certain that the indoor space is properly ventilated; • reduce levels of cockroach and dust mite particles; • reduce pet dander; • avoid or minimize use of pesticides indoors; • use low toxicity paints, sealers and caulks; • reduce the use of solvent-based dry cleaning and/or air out dry-cleaned clothes thoroughly before bringing into one's home; • avoid idling an internal combustion engine, such as a car, lawn mower or fork lift, in an enclosed space or near the entrance to one's home or workplace; and • change air filters frequently. • OPEN WINDOWS

35. Radon Gas • An invisible, odorless, tasteless gas that is radioactive • Radon is one of the elements produced when uranium decays. Uranium is found naturally in the earth and is most concentrated in porous soils overlying rocks that contain uranium. • Radon gas can enter homes and stick to dust particles which can then be breathed in. • The radon decay releases alpha particles which can lead to cancer

36. ASBESTOS • Fibers containing silica are used to reinforce cement, to make brake linings, residential siding, garments to protect fire fighters, and in insulation. • Used because the silica is strong and is heat resistant. • If these fibers get in the lungs, they can cut and scar them causing asbestosis. Victims have a hard time breathing and often die of heart failure. Mesothelioma is an aggressive cancer of the cells that surround organs such as the heart and lungs.

37. REVIEW • Name 3 indoor pollutants. • Name the source and effects of asbestos and radon. • Name 5 ways to reduce indoor pollutants