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Air Pollution. Primary Pollutants: Come from: Natural sources (volcanoes) Mobile sources (cars) Stationary sources (smoke stacks) Examples: Particle matter or soot (PM 10 ) Nitric oxide (NO) Nitrogen dioxide (NO 2 ) Sulfur dioxide (SO 2 ) Carbon dioxide (CO 2 ) Carbon monoxide (CO).
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Primary Pollutants: Come from: Natural sources (volcanoes) Mobile sources (cars) Stationary sources (smoke stacks) Examples: Particle matter or soot (PM10) Nitric oxide (NO) Nitrogen dioxide (NO2) Sulfur dioxide (SO2) Carbon dioxide (CO2) Carbon monoxide (CO) Secondary Pollutants: Result from chemical reactions of primary pollutants in the atmosphere Examples: Sulfur trioxide (SO3) Sulfuric acid (H2SO4) Ozone (O3) Air Pollution
Major Air Pollutants • Criteria air pollutants • Set of pollutants that cause smog, acid rain, and other health hazards • Emitted from industry, mining, transportation, power generation, and agriculture • Include: ozone, particulate matter, carbon monoxide, sulfur dioxide, nitrogen oxides, and lead
Nitrogen Dioxide (NO2) Forms when fuels burn at high temperatures, from forest fires, volcanoes, and bacteria in soil Forms nitric acid in the air acid deposition When inhaled irritates the lungs Supresses plant growth May be a carcinogen Ozone (O3) Formed by the reaction of sunlight and NOx and VOCs Causes: Lung irritation and damage Bronchial constriction Coughing Wheezing Eye irritation In high atmosphere forms ozone layer = good Major Air Pollutants
Peroxyacyl Nitrates (PANs) Hydrocarbons + O2 +NO2 + light CH3COOONO2 (PAN) Stable in the atmosphere transport unstable compounds far away from urban centers Cause eye irritation In high concentrations damage vegetation Sulfur Dioxide (SO2) Produced by burning high-sulfur oil or coal, smelting of metals, and paper manufacturing Combines with water vapor to produce acid rain Acid rain causes: Reduction in plant productivity Breathing difficulties Destroys buildings Acidifies water supply Major Air Pollutants
Suspended Particulate Matter (PM10) Particles with a diameter of 1/7 of a human hair or less Include smoke, dust, diesel soot, lead, and asbestos Cause lung irriation and damage Are mutagens, teratogens (interfers with development), and carcinogens Reducing PM10 would produce health benefits 10 times grater than reducing all other air pollutants combined Volatile Organic Compounds (VOCs) Include organic compounds that have a high vapor pressure Found in paints, aerosol sprays, dry-cleaning fluids, and industrial solvents Cause respiratory irritation and damage Most are carcinogens Cause liver, kidney, and central nervous system damage May be greater concentrations indoors than outdoors Major Air Pollutants
Measurement Units • ppm (Parts per million) • 1ppm means every 999,999 particles of air there is 1 particle of pollutant • Others: • ppb or nano: parts per billion • ppt or pico: parts per trillion
Smog • Industrial: tends to be sulfur based • Called “grey-air” smog • Photochemical: nitrogen based • Catalyzed by UV radiation • Called “brown-air” smog
Formation of photochemical smog • Occurs during specific times of the day • Net Result: NO + VOCs + O2 + uv O3 + PANs
Case Study – Great Smog of ‘52 • A period of cold weather combined with windless conditions to collect airborne pollutants (most form coal) to produce a thick layer of grey smog over London December 5 – 9 1952 • Dispersed quickly after a change in weather • 100,000 people became ill • 12,000 died
Catalytic Converters • Converts toxic chemicals in engine exhaust to less noxious substances • Inside a catalyst stimulates a chemical reaction in which noxious by-products of combustion are converted to less toxic substances
Catalytic Converters • 3 way converter: • Reduction of nitrogen dioxides to nitrogen and oxygen • Oxidation of carbon monoxide to carbon dioxide • Oxidation of unburned hydrocarbons to carbon dioxide and water.
Pros Remove hydrocarbons and other harmful emissions Cons Do not reduce carbon dioxide emissions Release nitrous oxide which contributes to climate change Catalytic converters
Wet: Acid rain Acid fog Acid snow Water flows over the ground and affects plants and animals Dry Acid gases Acid particles Particles fall out of atmosphere and onto buildings, cars, trees, etc. Rain can wash particles off features in the environment contributing to acid rain Types of Acid Deposition
Acid depositions • Due to: • Sulfur dioxide • Nitrogen oxides • Environmental effects: • Acidify streams • Damage forests soils through nitrogen saturation • Acid shock (rapid melting of snow pack with acid particles) • Leaches essential plant nutrients from the soil
Heat Islands • Occur in metropolitan areas • Urban air is 10°F (6°C) warmer than surrounding environment
Causes: Buildings reduce radiation of heat to the atmosphere Thermal properties of surface material (asphalt, bricks, concrete) store heat longer Lack of vegetation and standing water increase temperatures Human activities (automobiles, industry, etc.) Effects: Combined with high levels of pollution leads to a localized green house effect Excessive temperatures can lead to deaths Meteorological effects: Alter local wind patterns Alter the development of clouds and fog Alter number of lighting strikes Change precipitation patterns Heat Islands
Combating urban heat islands • Increasing amount of landscaping in parks and on top of buildings • Increasing the amount of light or reflective material
Temperature Inversions • Occur when air temperature increases with height above the ground • Usually occur at night when the surface cools, cooling the air above it • Can lead to smog being trapped near the ground human health problems (asthma, emphysema, and increase in lung cancer)
Case Study- Donora, PA 1948 • Smog from the local zinc and steel smelting plants settled in the valley where Donora was located • 20 people asphyxiated and 7,000 went to the hospital (total population of the town was 14,000) • Four days later, wind cleared the toxins from the town • Led to first meaningful federal and state laws to control air pollution
Indoor air pollution is 25% to 60% greater than outdoor pollution Sick Building Syndrome (SBS) describes a combination of ailments associated with a place of work or residence Common Pollutants: Mold Bacteria Carbon monoxide Radon Allergens Asbestos Tobacco smoke Formaldehyde VOCs Indoor Air Pollution
SBS symptoms • Headaches • Breathing difficulties • Allergies • Asthma • Cancer • Emphysema • Nerve disorders
Air Pollution Remediation and Reduction Strategies • Emphasizing tax incentives for pollution control rather than fines and penalties • Setting legislative standards for energy efficiency • Increasing funding for research into renewable energy resources • Incorporating incentives for reducing air pollution into trade policies • Distributing solar cook stoves to developing countries to replace coal and firewood
Air Pollution Remediation and Reduction Strategies • Phasing out two-cycle gasoline engines • For issues involving SBS • Modify building codes to control materials used in construction • Replace and repair areas that have received water damage to control for mold • Use paints, adhesives, solvents, cleaning products, and pesticides in well-ventilated areas and during non-occupancy • Increase the number of complete air exchanges in buildings • Ensure proper maintenance of HVAC systems • Providing incentives to use mass transit
Combating Acid Rain • Design more efficient engines to reduce emissions • Reduce emissions in coal-burning power plants • Increase penalties on stationary sources • Provide incentives to consumers to purchase Energy Star products • Increase CAFE standards
Designed to achieve significant environmental reduction and public health benefits through reductions in emission of sulfur and nitrogen compounds at a low cost to society Encourages energy efficiency and pollution prevention Strategies: Allowance trading system Opt-in program, allows non-affected industrial and small utility units to participate in trading Setting new NOx emission standards Permit process that affords flexibility in selecting most cost-effective approach Continuous Emissions Monitoring (CEM) provide accounting of excess emissions EPA’s Acid Rain Program
Designed to control pollution on a national level Act has been amended in 1967, 1977, 1990 Requires EPA to design and enforce regulations to protect the public from airborne contaminants Required comprehensive federal and state regulations for both stationary and mobile sources of pollution Expanded federal enforcement authority Addressed acid rain, ozone depletion, and toxic air pollution Established new gasoline reformulation requirements 1st major environmental law to include provisions for citizen law suits Clean Air Act (1963)
Clean Air Act (1963) is responsible for: • Estimates responsible for: • Saving 15,000 lives per year • Reducing bronchitis by 60,000 cases each year • Reducing respiratory related illnesses by 9,000 cases each year
Relevant laws • Air Pollution Control Act (1955) • 1st legislation regarding air pollution • Identified air pollution as a national problem • Announced research and additional steps were necessary • Basically meant to make public aware of problem • National Environmental Policy Act (1970) • Created EPA • Mandated the creation of Environmental Impact Statements
Relevant laws • Montreal Protocol (1989) • Agreement among nations to phase out chemicals that damage the ozone layer • Pollution Prevention Act (1990) • Requires industry to reduce pollution at its source • Reduction can be in terms of volume and/or toxicity
Kyoto Protocol (1997 and 2001) • An agreement among 150 nations requiring greenhouse gas reductions • Would have required a 7% decrease in greenhouse gas emissions compare to 1990 levels over a 5 year period • US felt protocol held developed and developing countries to different standards • Concerned the costs were too high and time frame too short; climate change deniers • 2012: Canada, Japan, and Russia joined the US saying they would not sign an agreement unless unbalanced requirements for developed and developing countries were changed
Noise Pollution • Unwanted human-created sound that disrupts the environment • Transportation noise (dominant) • Office equipment • Factory machinery • Appliances • Power tools • Audio entertainment systems
Short Term Damage to inner ear results in hearing loss Cardiovascular problems Gastric-intestinal problems Decrease alertness and ability to memorize Nervousness, pupil dilation Decrease in the visual field Long term Insomnia Nervousness Bulimia chronically high blood pressure Anxiety Depression Sexual dysfunction Noise Pollution Effects
Road noise: Use of noise barriers, limitations on vehicle speed newer roadway surface technologies traffic control limiting times for heavy duty vehicles Air line Noise: Developing quieter jet engines controlling take off and landing times Industrial Noise: New technologies Instillations of noise barriers in the work place Residential Noise: Regulate noise from power tools, garden equipement, loud radios Noise Pollution Control Measures
Relevant Law • Noise Pollution Control Act (1972): • Establishes a national policy to promote an environment free from noise that jeopardizes health • Establishes a means for the coordination of federal research activities in noise control • Authorizes establishment of federal noise standards and products • Provides information to the public respecting noise emission and noise reduction characteristics of such protocol