chapter 12- air what causes air pollution?. what causes air pollution? clean air: mostly n & o,...
TRANSCRIPT
Chapter 12- AIR
What Causes Air Pollution?
What causes air pollution?
Clean air: Mostly N & O, small amounts of argon, CO2 and H2O.
Air pollution- harmful substances in the air @ unhealthy levels. Most from human activities Natural sources: volcanoes, dust,
pollen and spores
Primary and Secondary Pollutants
Primary pollutants are put directly into air by human activity
Secondary pollutants form when primary pollutants come in contact with each other naturally occurring substances. Ex: Ground level ozone- Emissions
from cars and natural sources mix with oxygen and react with UV rays.
Sources of Primary Pollutants
Primary Air Pollutants
Sources of Primary Air Pollutants
Particulate matter- Fine and coarse particles From cement plants, mining,
incinerators, wood-burning fireplaces, fields, and roads
Volatile Organic Compounds (VOCs)- Carbon monoxide, nitrogen oxide, sulfur dioxide, and chemicals From household products, power plants,
and motor vehicles
The History of Air Pollution
2000 years ago, Roman philosopher, Seneca, complained of foul air.
1273, King Edward I made burning sea-coal illegal
Worse today due to burning of fossil fuels
Motor Vehicle Emissions
1/3 of air pollution Clean Air Act, 1970 & 1990, gives
EPA authority to regulate vehicle emissions Reduce lead in gasoline Catalytic converters 35% more fuel efficient with 95%
fewer emissions than 30 years ago
Motor Vehicle Emissions
California Zero-Emission Vehicle Program 1990, CA Air Resources Board est. ZEV prgm. Vehicles w/ no tail pipe emissions and no
emission control systems that deteriorate over time
By 2016, 16% of vehicles sold in CA will be ZEV Electric Advanced batteries Hydrogen fueled Low emission cars
Hybrid electric cars Methanol fueled cars
Industrial Air Pollution
Clean Air Act requires many industries to use scrubbers or other pollution-control devices Electrostatic precipitators- Remove dust
particles from smoke stacks Remove 20 million tons of ash from coal plants
each year Scrubbers- Remove harmful chemicals from
gases by spraying them with water. Ex: Removal of ammonia
Industrial Air Pollution
Temperature Inversions- The air above is warmer than the air below, trapping air pollution near the earth’s surface Cities in valleys or surrounded by mountains
(Ex: L.A.) Smog- Air pollution that hangs over
urban areas and reduces visibility Main cause: pollutants released by vehicles
and industry L.A., Denver, and Phoenix
Chapter 12-AIR
Air, Noise, and Light Pollution
Short-Term Effects of Air Pollution
Headache Nausea Irritation to eyes, nose, and throat Tightness in chest Coughing Upper respiratory infection Worsen emphysema and asthma
Long-Term Health Effects of Air Pollution
Emphysema Lung cancer Heart disease Worsen various medical conditions
Indoor Air Pollution
Air quality in buildings can be worse than outside due to substances found in carpet, furniture, paint, etc.
Ventilation is key to controlling Sick-building syndrome- Buildings
that are securely sealed and harbor mold, fungi, etc. Common in hot or cold areas
Indoor Air Pollution
Radon gas- Colorless, tasteless, and odorless Produced by decay of Uranium Seeps up through cracks and holes
where it adheres to dust Destroys genetic material in lung cells 2nd-leading cause of lung cancer
Indoor Air Pollution
Asbestos- Long, thin fibers valued for their strength Used as insulation and fire retardant Banned in early 1970s Cut and scar lungs- Asbestosis
Trouble breathing Eventual heart failure
Noise Pollution
Sound measured in decibels (dB) Intensity-loudness 120 dB causes pain
with continuous exposure causing permanent deafness
Unneeded noise can cause health problems Loss of hearing High blood pressure Stress
Light Pollution
No direct hazard to human health Inefficient lighting diminishes view of
night sky Inefficient lighting is energy waste
Light directed upward is lost into space Downward light is best Energy efficient light includes:
Not using when not needed Low pressure sodium sources
Chapter 12- Air
Section 3- Acid Precipitation
Acid Precipitation
Precipitation such as rain, sleet, or snow with a high concentration of acids
Sulfur and nitrogen oxides released when fossil fuels are burned Sulfuric and nitric acid fall as acid rain Pollutes water sources Kills living things
pH Scale
Power of hydrogen From 0 to 14 Acidic from 0 to 6
(lower more acidic) Acid rain 5 and below;
varies in different geographic areas
Normal rain contains carbonic acid at pH of ~ 6
Basic from 8 to 14 (higher more basic)
7 is neutral (pure water)
Affects Soils and Plants
Acidification- Increase in amount of acid in soil and water Nutrients dissolved and washed away Toxic metals are released
Aluminum causes root damage Sulfur dioxide clogs surface openings
of plants
Acid Rain and Trees
Affects Aquatic Ecosystems
pH changes kill aquatic plants, fish, and other aquatic animals
Aluminum from soil leaches into water;clogs gills of fish
Acidification worse in spring when snow melts Acid Shock- Sudden increase in acid levels
Fish die in large amounts Decreased egg production, hatches, and healthy
offspring for amphibians and living fish
Powdered limestone (calcium carbonate) neutralizes acid in water sources and soil
Acid Shock
Acid Precipitation and Humans
Toxins enter human body through crops, water and fish
Respiratory problems in children Commercial and sport fishing
affected by decreasing number of fish
Calcium carbonate dissolves, destroying monuments, etc.
International Conflict and Cooperation
Pollution is put out in a different area from where the acid precipitation may fall Ex: S. East Canada gets acid precipitation
from OH, IN, IL, PA, MO, WV, and TN pollution
Canada-U.S. Air Quality Agreement- 1991 Reduce acidic emissions and acid
precipitation