A Clean Environment: The Basis of Public Health

Clean Air: The Basis of Public Health

Air Pollution Events

  • Historical air pollution events highlight the dangers of air pollution:
    • London, 1952: A weather inversion caused over 4,000 deaths.
    • Donora, Pennsylvania, 1948: Experienced a similar weather inversion.
    • Los Angeles, 1950s and 1960s: Suffered severe smog.
  • Clean Air Act of 1970:
    • Established air quality standards.
    • Limited major pollutants.
    • Mandated emission reductions for automobiles and factories.

Criteria Air Pollutants

  • The Clean Air Act regulates six major air pollutants:
    • Particulate matter
    • Sulfur dioxide
    • Carbon monoxide
    • Nitrogen oxides
    • Ozone
    • Lead

Particulate Matter

  • Definition: Particulate matter is the most visible form of air pollution.
  • Sources: Often products of combustion.
  • Regulation:
    • Initially regulated as total particulates.
    • A six-city study linked higher death rates to more polluted cities.
    • Smaller particles are more dangerous due to deeper lung penetration.
    • EPA Standards:
      • 1987: Set standards for PM10 (particles with a diameter of 10 micrometers or less).
      • 1997, 2006, 2012: Established more stringent standards for PM2.5 (particles with a diameter of 2.5 micrometers or less).
  • Health Effects: Lung cancer, other lung diseases, and heart disease are proportional to PM2.5 exposure.

Sulfur Dioxide

  • Sources: Combustion of sulfur-containing fuels, especially coal.
  • Health and Environmental Effects:
    • Irritation of the respiratory tract.
    • Acid rain.
    • Potential for causing respiratory damage.
  • Progress: Levels have declined by 91% between 1980 and 2018.

Carbon Monoxide

  • Characteristics: Highly toxic gas.
  • Sources: Primarily motor vehicle exhaust.
  • Health Effects:
    • Especially harmful to patients with cardiovascular disease.
    • Causes headaches and impairs mental processes.

Nitrogen Oxides

  • Sources:
    • On-road motor vehicle exhaust.
    • Off-road equipment.
    • Power plant emissions.
  • Environmental Effects:
    • Responsible for the yellowish-brown appearance of smog.
    • Contribute to respiratory tract irritation.
    • Acid rain.
    • Ozone formation.

Ozone

  • Characteristics: Highly reactive variant of oxygen.
  • Formation: Produced by sunlight acting on other air pollutants.
  • Health Effects:
    • Irritates eyes and respiratory system.
    • Increases mortality from cardiovascular and respiratory diseases.

Lead

  • Health Effects:
    • Damages the nervous system, blood, and kidneys.
    • Poses a special risk to the development of children’s intellectual abilities.
  • Regulation:
    • Was used in leaded gasoline but was phased out in the U.S. by 1995.
    • Has decreased dramatically as an air pollutant.

Other Air Pollutants

  • 1990 Clean Air Act Amendments: Directed the EPA to set standards for 187 specific chemicals.
  • EPA Action: As of 1993, the EPA had acted only on asbestos, mercury, beryllium, benzene, vinyl chloride, arsenic, radionuclides, and coke-oven emissions.
  • Challenges: Controversy exists for each standard.

Strategies for Motor Vehicles

  • Tailpipe emissions limits
  • Vapor recovery systems on gasoline pumps
  • Inspection and maintenance requirements
  • Requirements that auto makers develop zero emission vehicles
  • Public transportation development
  • Encouraging carpooling

Strategies for Industrial Sources

  • Scrubbers on smokestacks
  • Less polluting fuels (limits on high-sulfur coal)
  • Market approach: buy and sell pollution allowances
  • New Source Review provision
    • Industry has flouted the rules.
    • Lawsuits have been pressed by states.
    • Bush Administration replaced this provision with the weaker Clear Skies Initiative.
  • Emergency Planning and Community Right-to-Know Act

Good News

  • Air pollution has decreased 54% since 1970.
  • California, with the worst pollution, has instituted many special regulations and incentives with some success.

Indoor Air Quality

  • People spend more time indoors than out.
  • “Sick building syndrome”
  • Sources of indoor air pollution:
    • Tobacco smoke
    • Wood-burning stoves and fireplaces
    • Gas ranges and furnaces
    • Radon
      • Danger is unclear.
      • It seeps up from soil and rock.
      • It can be sealed out.
    • Formaldehyde
      • Insulation, particleboard, plywood, some floor coverings, and textiles
      • Regulated by Dept. of Housing and Urban Development
    • Consumer products
      • Pesticides, drywall from China, dry-cleaning solvents, paints and paint thinners, hair spray, and air fresheners
      • Use with caution.
    • Microbes
      • Legionella
      • Hantavirus
    • Allergens
      • Mold, house mites, and animal dander

Global Effects of Air Pollution

  • Acid rain damages forests and crops, turns lakes and rivers acidic, and kills fish and plants.
  • Depletion of the ozone layer is an effect of certain air pollutants.
    • Production of CFCs are being phased out.
    • Montreal Protocol in 1987
    • Ozone layer has stabilized.
  • Carbon dioxide produced by burning fossil fuels causes the greenhouse effect and global warming.

Discussion Questions

  • Do you know how polluted your community’s air is?
    • Some newspapers report daily air pollution levels, especially in the summer.
    • Visit the EPA website, www.epa.gov, and look for information on air pollution in your city/region.
  • How have provisions of the Emergency Planning and Community Right-to-Know Act of 1988 and the Clean Air Act amendments of 1990 overcome some of the problems caused by the overregulation described in Chapter 12?
  • Conduct a survey of your home.
    • How many sources of indoor air pollution can you find?
  • Visit the website of the National Center for Environmental Health, www.cdc.gov/nceh.
    • Find links to state information on indoor air.
    • What does your state’s website say about indoor air pollution?

Solid and Hazardous Wastes

Before the 1970s

  • Open dumps were:
    • Outlawed by the Resource Conservation and Recovery Act (RCRA) in 1976
    • Supported large populations of vermin and produced toxic leachates that contaminated groundwater
  • Garbage was burned in incinerators or in the open.
    • Outlawed by the Clean Air Act of 1970
  • Garbage was poured into rivers, lakes, or oceans.
    • Outlawed by the Clean Water Act (1972) and the Marine Protection, Research, and Sanctuaries Act (1972)

Sanitary Landfills

  • Site should be dry, impervious clay soil.
  • Lined with plastic
  • Drained of liquids
  • Vented to control explosive gases
  • Tipping fee is the cost of disposing of one ton of municipal waste.
    • Highest cost is in the northeast.
  • Big drawback is that landfills use a lot of space.

Alternatives to Landfills

  • Reduce: Buy only what is needed; avoid excessive packaging.
  • Reuse: Use reusable items rather than disposable.
  • Recycle: Include composting
    • Can be encouraged through financial incentives
    • Can be mandated
  • Waste-to-energy incineration
    • Still a pollution concern

Hazardous Wastes

  • Love Canal, New York, 1978
  • Times Beach, Missouri, 1972–1976
  • Resource Conservation and Recovery Act (RCRA), 1976, 1984
    • All hazardous wastes accounted for “from cradle to grave”
    • Wastes from petroleum refining, pesticide manufacturing, some pharmaceuticals
    • Ignitable, corrosive, reactive, toxic wastes

Superfund

  • Comprehensive Environmental Response, Compensation, and Liability Act, 1980
    • The law required emergency cleanup of old waste sites.
    • The fund would be paid for by a tax on industry.
  • Superfund controversy
    • Much effort was focused on determining who is liable.
    • Tax was not reauthorized in 1995.
  • American Recovery and Reinvestment Act allocated $600 million for further cleanup of Superfund sites.

Coal Ash

  • Is waste from coal-burning power plants
  • Is stored in open dumps, often near rivers
  • Contains heavy metal contaminants, which leach into nearby water
  • Is unregulated by the EPA
  • Major spill in 2008 on the banks of the Tennessee River brought attention to coal ash.

Discussion Questions

  • Estimate how much solid waste you generate in a day.
    • How can you reduce the volume of this waste?
  • Visit the EPA’s Superfund site map, ww https://www.epa.gov/superfund, and identify a hazardous waste site near you.
    • What is being done to clean it up?
  • Visit the website of the Agency for Toxic Substances and Disease Registry, www.atsdr.cdc.gov.
    • What information does it have on health effects of hazardous substances?
    • Look for information on a few specific substances that you may be concerned with. If you do not have any specific concern, look for information on benzene, nitrogen sulfide, and ozone.

Conclusion

  • As concern about environmental pollution has grown, the problem of disposing of solid wastes has become more difficult to resolve.
  • Solid-waste disposal is now confined to sanitary landfills, which must meet federal standards.
  • Hazardous wastes present an especially difficult disposal problem.
  • Recent spills from coal ash dumps into rivers and other bodies of water have called attention to the toxic contaminants contained in the ash, poisoning wildlife and threatening human health.