1. Aim: What are the major outdoor air pollutants?

2. Major Outdoor Air Pollutants: Carbon Oxides
CO: Carbon Monoxide
Forms during combustion of carbon containing materials.
Problems: heart attacks, asthma, emphysema.
Nausea, dizziness, confusion, death!
CO2: Carbon Dioxide
93% forms naturally in C cycle. Rest from humans.
Problems: heat exhaustion, loss of food production
Cars, factories, smokestacks, burning forests
Burning fossil fuels

4. Major Outdoor Air Pollutants: Nitrogen Oxides
(NO) Nitric oxide
Forms under high temps w/combustion
(HNO3) Nitric acid
Forms when NO2 reacts w/water vapor
Problems: irritate eyes. Nose, throat, lung conditons, lower visibility, stunt plant growth.
Car engines, coal power plants, lightening
Photochemical smog: citities

6. Major Outdoor Air Pollutants: Sulfur Oxides
(SO2 ): Sulfur Dioxide
Forms naturally: 1/3 sulfur cycle. 2/3 from human combustion.
Problems: In atm. Converts to aerosols.
(H2SO4): Sulfuric Acid
In aresols
Problems: reduce visibility, breathing problems, damage crops, water supplies, corrode metal, damage buildings.
Coal and industrial plants, smelting,
ASIAN BROWN CLOUD

7. Major Outdoor Air Pollutants **Particulates**
Suspended particulate matter (SPM) by EPA
Fine
Ultrafine
Sources: 62% natural from dust, wildfires, sea salt.
38% from humans: cars, coal plants, factories, construction.
Human health and environmental impact

8. Major Outdoor Air Pollutants
(O3): Ozone
Problems: respiratory issues, lung and heart disease. Damages plants, rubber, fabrics, and paints.
(VOCs): Volatile organic compounds
Forms: naturally or exits in atmosphere. Comes from plants
CH4: Methane more harmful then CO2 at warming.
Photochemical smog
Plants, wetlands, humans, cows, landfills, oil and natural gas wells.

9. METHANE

10. Chemical Reactions That Form Major Outdoor Air Pollutants
Table 18-1
Table 18-1, p. 470

11. Statue Corroded by Acid Deposition and Other Forms of Air Pollution, RI, U.S.
Figure 18.7: Acid deposition and other forms of air pollution have corroded this statue in Newport, Rhode Island (USA).
Fig. 18-7, p. 471

12. Case Study: Lead Is a Highly Toxic Pollutant (1)
In air, water, soil, plants, animals
Does not break down in the environment
Human health and environmental impact
Children most vulnerable
Can cause death, mental retardation, paralysis

13. Case Study: Lead Is a Highly Toxic Pollutant (2)
Reduction of lead (Pb)
Unleaded gasoline
Unleaded paint
Still problems
15-18 million children have brain damage
Need global ban on lead in gasoline and paint

14. Solutions: Lead Poisoning, Prevention and Control
Figure 18.8: Individuals matter.
There are several ways to help protect children from lead poisoning. Questions: Which two of these solutions do you think are the most important? Why?
Fig. 18-8, p. 472

15. Science Focus: Detecting Air Pollutants
Chemical instruments
Satellites
Lasers and remote sensors
Biological indicators
Lichens

16. Natural Capital: Lichen Species, Vulnerability to Air Pollutants
Figure 18.A: Natural capital.
Old man’s beard (Usnea trichodea) lichen (left) is growing on a branch of a larch tree in Gifford Pinchot National Park in the state of Washington (USA), and red and yellow crustose lichens (right) are growing on slate rock in the foothills of the Sierra Nevada near Merced, California (USA). Scientists can use such lichens to detect the presence of specific air pollutants and to track down their sources.
Fig. 18-A, p. 473

17. Burning Coal Produces Industrial Smog
Chemical composition of industrial smog
Reduction of this smog in urban cities of the United States
China and smog
Human deaths
Need strong standards, especially for coal burning

18. How Pollutants Are Formed from Burning Coal and Oil, Leading to Industrial Smog
Figure 18.9: This is a greatly simplified model of how pollutants are formed when coal and oil are burned. The result is industrial smog.
Fig. 18-9, p. 474

19. Carbon monoxide (CO) and carbon dioxide (CO2)
Ammonium sulfate [(NH 4 )2SO4]
Ammonia (NH3)
Sulfuric acid (H2SO4)
Carbon monoxide (CO) and carbon dioxide (CO2)
Water vapor (H2O)
Sulfur trioxide (SO3)
Oxygen (O2)
Sulfur dioxide (SO2)
Burning coal and oil
Figure 18.9: This is a greatly simplified model of how pollutants are formed when coal and oil are burned. The result is industrial smog.
Oxygen (O2)
Sulfur (S) in coal and oil
Carbon (C) in coal and oil
Fig. 18-9, p. 474

20. Industrial Smog in India
Figure 18.10: Industrial smog hangs over a factory in an Indian city.
Fig , p. 474

21. Sunlight Plus Cars Equals Photochemical Smog
Chemical composition
Sources
VOCs + NOx + Heat + Sunlight yields
Ground level O3 and other photochemical oxidants
Aldehydes
Other secondary pollutants
Human health and environmental impact

22. A Model of How Pollutants That Make Up Photochemicals Are Formed
Figure 18.11: This is a greatly simplified model of how the pollutants that make up photochemical smog are formed.
Fig , p. 475

23. Global Outlook: Photochemical Smog in Santiago, Chile
Figure 18.12: Global Outlook: Photochemical smog is a serious problem in Santiago, Chile. Question: How serious is photochemical smog where you live?
Fig , p. 475

24. Several Factors Can Decrease or Increase Outdoor Air Pollution (1)
Outdoor air pollution may be decreased by
Settling of particles due to gravity
Rain and snow
Salty sea spray from the ocean
Winds
Chemical reactions

25. Several Factors Can Decrease or Increase Outdoor Air Pollution (2)
Outdoor air pollution may be increased by
Urban buildings
Hills and mountains
High temperatures
Emissions of VOCs from certain trees and plants
Grasshopper effect
Temperature inversions
Warm air above cool air prevents mixing

26. A Temperature Inversion
Figure 18.13: Frequent thermal inversions and the presence of many cars and industries lead to photochemical smog in downtown Los Angeles, California (USA).
Fig , p. 476

27. Summary:
Should construction of tall smokestacks be banned in an effort to promote greater emphasis on preventing air pollution and acid deposition? Explain.

28. Homework:
Read Chapter 18 Pages