1. Air
Chapter 12

2. Section 1: What Causes Air Pollution?

3. Primary and Secondary Pollutants
Air Pollution – Harmful substances built up in the air to an unhealthy level
Pollutants can be from human activity – industry soot
Pollutants can be natural – volcanic ash
Primary Pollutant – put into air directly by human activity
Soot from smoke
and fires
Primary and Secondary Pollutants

4. 5 Types of Primary Pollutants and Their Sources
Primary and Secondary Pollutants

5. Primary and Secondary Pollutants
Secondary Pollutant – form when primary pollutants react with each other or natural substances
Ground Level Ozone – is formed when car emissions (primary) interact with oxygen and UV rays (both natural)
Primary and Secondary Pollutants

6. Is air pollution new? Clean Air Act 1970 –
In 1273 King Edward I declared burning coal illegal
“Be it known that whosoever shall be found burning coal shall suffer the loss of his head”
Clean Air Act 1970 –
Overseen by Environmental Protection Agency (EPA)
Regulates the emissions (what comes out the tailpipe) of automobiles
The EPA required the gradual elimination of lead in gasoline. To date lead pollution has been reduced by more than 90 % in US.
California – Zero Emission Law – Is that possible? Battery operated vehicles are the only “true” ZEVs (zero emission vehicles)

7. Industrial Air Pollution
Industrial plants burn fossil fuels
Burning releases – Sulfur Dioxide and Nitrous Oxide
Power Plants emit 2/3 of ALL SO2 and 1/3 of ALL NO
VOCs (Volatile Organic Compounds) - chemical compounds that form toxic fumes
Given off by – Oil refineries, Dry Cleaners, Chemical plants
Clean Air Act Requires Industries to use:
Scrubber: cleans emissions of plants by washing it and filtering it
Electrostatic Precipitator: uses static charges to get particulates to clump together and collect, clean gas continues on. (used in cement factories/coal burning plants)
Industrial Air Pollution

8. Smog: Air pollution that hangs over urban areas and reduces visibility

9. Temperature Inversion:
Air circulation usually stops pollution from accumulating to dangerous levels.
Inversions trap pollution near the Earth’s Surface
Temperature usually decreases with altitude
But a warm layer above a cold layer will trap pollution
(Hot air rises, right? Hot smoke rises, but if atmosphere is just as warm, the smoke stays put)

11. That’s all for 12.1
Time for a reading quiz

12. Section 2: Air, Noise, and Light Pollution

13. Effects of Air Pollution on Health
Many air pollution effects are short term
Can be reversed when exposure is decreased
Short term effects:
Nausea
Headaches
Eye Irritations
Coughing
Upper respiratory infections
(bronchitis, pneumonia)
Will make asthma worse

14. Effects of Air Pollution on Health
Many air pollution effects are long term
Cannot be reversed when exposure is decreased
Long term effects:
Emphysema
Lung Cancer
Heart Disease
May damage lungs of young children

15. Air inside a building is sometimes WORSE than air outside
Chemicals used in making carpets, furniture, paints can pollute indoor air
Sick Building Syndrome – buildings with very poor air quality
Found in hot climates where buildings are sealed to keep out heat.
Fungi can grow and there is no release of the toxic chemicals released from carpet, paint etc.
All builds up to drastically reduce indoor air quality
Indoor Air Pollution

17. Indoor Air Pollution Preventing bad indoor air pollution Radon Gas
Remove the source of the pollution
Remove carpet, new paint
Good ventilation to mix the indoor air with outdoor air
Decreases the amount of pollution per unit of air
Radon Gas
Colorless, odorless gas – 2nd leading cause of
lung cancer
Occurs after uranium decays, found naturally in the earth, can seep into houses.
Have a radon detector in the house
Indoor Air Pollution

18. Indoor Air Pollution Asbestos
A fire resistant substance used in building materials before the 1970s.
When inhaled the fibers can cut and scar the lungs leading to breathing difficulties and heart failure.
Billions of dollars have been spent in asbestos removal
Indoor Air Pollution

19. Noise Pollution Defined as unwanted sound
Noise kills nerve cells in the ear
12% of teens have permanent hearing loss
Intensity of sound is measured in decibels
120 dB is at the threshold of pain. Noise levels greater than this can cause permanent damage.
Protection from noise pollution:
Mufflers on autos and yard equipment
MP3 players in Europe can only go up to 100 dB
Ear protection

20. Light Pollution Not a direct hazard to human health
Does impact environment and enjoyment of night sky.
Bigger threat is wasted energy
Upward directed light is wasted, only goes to space

21. That’s all for 12.2
Time for a reading quiz

22. Section 3: Acid Precipitation

23. What Causes Acid Precipitation?
Acid precipitation is rain with a high concentration of acids
pH measures acid concentration
Low numbers are more acidic. Below 7 is acidic. The closer to zero – the more acidic.
Each change in pH (1 to 2) indicates a ten times difference in acidity
Normal rain has a pH of 5.6, acid precipitation starts at 5.0
What Causes Acid Precipitation?

24. What Causes Acid Precipitation

25. How Does Acid Precipitation Affect Soils and Plants
Acidification – Increase of acid in soils or lakes
Acid chemically reacts with soil minerals
Some nutrients are dissolved and washed away from where plants can use them
Metals like aluminum are released into the soil and possibly absorbed
High enough levels of these metals can be toxic
How Does Acid Precipitation Affect Soils and Plants

26. Acid Precipitation and Aquatic Ecosystems
Aquatic animals live within a very narrow pH range
Acid rain changes pH level of lake and kills fish
Acid precipitation leaches metals like aluminum from soil near lake/river
Metals accumulate in fish bodies until reach toxic levels
Acid Shock
In the spring when acid
snow melt and flows into
rivers and lakes the sharp
change in pH kills massive
amounts of aquatic creatures

27. Acid Precipitation and Humans
Humans depend on plants, animals, and seafood items for food
If plants, animals, fish die off we lose food sources.
Toxic metals taken in by plants, animals, fish also accumulate in us and can reach toxic levels
Aesthetics – Statues and buildings are deteriorating due to acid rain

28. Controlling Acid Rain
Acid rain is hard to regulate because the pollution that causes it blows with the wind.
One country’s pollution could float into another country causing acid rain there.
Countries are signing Air Quality agreements with each other to help reduce polluting emissions

29. That’s all for 12.3
Time for a reading quiz