AIR POLLUTION

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AIR POLLUTION

• Gases, liquids, or solids in atmosphere in high
  enough levels to harm.

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TYPES OF AIR POLLUTION

• Primary air pollutants
• Enter directly into atmosphere
• Comes from transportation and industries
• Secondary air pollutants
• Harmful chemicals that from other substances
  released into the atmosphere
• Outdoor
• Indoor
• Photochemical smog
• Industrial smog

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MAJOR CLASSES

• Particulate matter
• Nitrogen oxides
• Sulfur oxides
• Carbon oxides
• Hydrocarbons
• Ozone
• Air toxics

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PARTICULATE MATTER

• Particles in atmosphere
• Dust solid matter
• Mists liquid suspensions
• Reduces visibility
• Irritation of the respiratory tract
• Stationary sources (i.e. industry)

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NITROGEN OXIDES

• Collectively known as NOx
• Inhibit plant growth
• Asthma (airway constriction)
• Global warming (greenhouse gas)
• Corrodes metals
• Stationary sources
• Photochemical smog

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SULFUR OXIDES

• Primary air pollutant Sulfuric acid
• Acid deposition
• Damages plants
• Corrodes metals, damages stone and other
  materials
• Irritates the respiratory tracts of humans and
  animals
• Stationary sources

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CARBON OXIDES

• CO2 is greenhouse gas
• Global warming
• CO is poisonous
• Reduces bloods ability to transport oxygen
• Headaches and fatigue
• Stationary sources

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OZONE (O3)

• Man-made pollutant in troposphere
• Component of photochemical smog
• Lowers crop yields
• Greenhouse gas
• Burning eyes, coughing, chest discomfort
• Asthma attacks
• Suppresses the immune system

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REAL WORLD EXAMPLES

• Chattanooga, TN
• Worst air pollution in the 1960s
• Reached attainment status by the late 1980s
• Blue Ridge Mountains
• Haze caused by hydrocarbon emissions from tree
  leaves

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URBAN AIR POLLUTION

• Smog (London, England 100 years ago)
• Industrial smog London-type smog
• Peppered moths
• Worse time is the winter (fuel burning)
• Photochemical smog Sunlight and chemicals react
• Brownish-orange haze
• Los Angeles
• Worse time is the summer (more sunlight)
• Injures plant tissues

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TOPOGRAPHY AND AIR POLLUTION

• Variations make air mix
• Air near the ground is warmer
• Temperature inversions
• The air near the ground is colder
• Pollutants remain near the ground
• Worse in valleys and near the coast

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CONTROLLING AIR POLLUTION

• Smaller, more fuel-efficient cars
• Smokestacks with scrubber
• Watering dry soil in a construction site
• No-tillage farming
• Natural gas (low-sulfur fuel)
• Solar energy
• Mass transit
• Catalytic converters (car smog devices)

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AIR POLLUTION IN US

• Clean Air Act of 1970, 1977 and 1990
• Federal limits on specific air pollutants
• Focus Pb, particulates, SO2, CO, NOx, and O3)
• Air quality gradually improving
• Non-attainment areas marginal to extreme
• L.A. is extreme but improving

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REAL WORLD EXAMPLES

• Los Angeles
• Some of the worst smog
• Temperature inversions
• 1969 California became the 1st state to enforce
  emission standards
• L.A. now has strict smog controls
• Now has the cleanest air since the 1950s
• Should reach attainment by 2010

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AIR POLLUTION IN DEVELOPING COUNTRIES

• Low priority
• Heat with coal, animal dung or wood
• Old vehicles
• Leaded gasoline
• Retard childrens growth and cause brain damage
• Cause problems in developed countries
• Compounds stay in atmosphere
• Enter food chain causing biological magnification

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INDOOR AIR POLLUTION

• Most sever type
• Closed up houses, businesses and cars
• Sick building syndrome
• Some types of pollutants Radon, CO, NO2 ,
  cigarette smoke, formaldehyde, cleaners, germs,
  pollen
• Asthma rare disease until 50 years ago
• Asbestos is a natural mineral used in building
  materials and insulation
• Fibers are inhaled into the lungs causing lung
  cancer

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REAL WORLD EXAMPLES

• Mexico City
• Worlds 4th largest city
• Most polluted air
• Breathing the air is like smoking 2 packs of
  cigarettes a day
• Some improvement but not enough enforcement

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THE END