Air Pollution

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Air Pollution

• Mexico City, Mexico

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NOX What is it? Where does it come from?

• Nitrogen oxides, or NOx, is the generic term for
  a group of highly reactive gases, all of which
  contain nitrogen and oxygen in varying amounts.
• Many of the nitrogen oxides are colorless and
  odorless.
• However, one common pollutant, nitrogen dioxide
  (NO2) along with particles in the air can often
  be seen as a reddish-brown layer over many urban
  areas
• Nitrogen oxides form when fuel is burned at high
  temperatures, as in a combustion process.
• Primary Sources motor vehicles, electric
  utilities, and other industrial, commercial, and
  residential sources that burn fuels.

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Chief Causes for Concern

• One of the main ingredients involved in the
  formation of ground-level ozone, which can
  trigger serious respiratory problems.
• Reacts to form nitrate particles, acid aerosols,
  as well as NO2, which causes respiratory
  problems.
• Contributes to formation of acid rain.
• Contributes to nutrient overload that
  deteriorates water quality.
• Contributes to PM, which causes reduced
  visibility most noticeable in national parks.
• Reacts to form toxic chemicals.
• Contributes to global warming.

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Chief Causes for Concern

• NOx can be transported over long distances,
  following the pattern of prevailing winds in the
  U.S.
• This means that problems associated with NOx are
  not confined to areas where NOx are emitted.
• Therefore, controlling NOx is often most
  effective if done from a regional perspective,
  rather than focusing on sources in one local
  area.

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Chief Causes for Concern

• NOx emissions are increasing.
• Since 1970, EPA has tracked emissions of the six
  principal air pollutants - carbon monoxide, lead,
  nitrogen oxides, particulate matter, sulfur
  dioxide, and volatile organic compounds
• Emissions of all of these pollutants have
  decreased significantly except for NOx which has
  increased approximately 10 percent over this
  period

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Health and Environmental Impacts

• Ground-level Ozone (Smog) - is formed when NOx
  and volatile organic compounds (VOCs) react in
  the presence of heat and sunlight.
• Children, people with lung diseases such as
  asthma, and people who work or exercise outside
  are susceptible to adverse effects
• Damage to lung tissue and reduction in lung
  function.
• Ozone can be transported by wind currents and
  cause health impacts far from original sources.
• Millions of Americans live in areas that do not
  meet the health standards for ozone.
• Other impacts from ozone include damaged
  vegetation and reduced crop yields

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Health and Environmental Impacts

• Acid Rain - NOx and SO2 react with other
  substances in the air to form acids which fall to
  earth as rain, fog, snow or dry particles. More
  on Acid rain
• Some may be carried by wind for hundreds of
  miles.
• causes deterioration of objects and causes lakes
  and streams to become acidic and unsuitable for
  many fish.
• Particles - NOx reacts with ammonia, moisture,
  and other compounds to form nitric acid
• Human health concerns include effects on
  breathing and the respiratory system, damage to
  lung tissue, and premature death.
• Small particles penetrate deeply into the lungs
  and can cause or worsen respiratory disease

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Health and Environmental Impacts

• Water Quality Deterioration - Increased nitrogen
  loading in water bodies, particularly coastal
  estuaries, upsets the chemical balance of
  nutrients used by aquatic plants and animals.
• Additional nitrogen accelerates "eutrophication,"
  which leads to oxygen depletion and reduces fish
  and shellfish populations.
• NOx emissions in the air are one of the largest
  sources of nitrogen pollution in the Chesapeake
  Bay.
• Visibility Impairment - Nitrate particles and
  nitrogen dioxide can block the transmission of
  light, reducing visibility in urban areas and on
  a regional scale in our national parks.

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Health and Environmental Impacts

• Global Warming - One member of the NOx, nitrous
  oxide, is a greenhouse gas.
• It accumulates in the atmosphere with other
  greenhouse gasses causing a gradual rise in the
  earth's temperature.
• This will lead to increased risks to human
  health, a rise in the sea level, and other
  adverse changes to plant and animal habitat.
• Toxic Chemicals - In the air, NOx reacts readily
  with common organic chemicals and even ozone, to
  form a wide variety of toxic products, some of
  which may cause biological mutations.
• Examples of these chemicals include the nitrate
  radical, nitroarenes and nitrosamines

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The EPAs Efforts to Reduce NOx

• Emissions standards for motor vehicles
• Since the 1970's, EPA has required motor vehicle
  manufacturers to reduce NOx emissions from cars
  and trucks.
• In the last ten years, NOx emissions from highway
  vehicles decreased by more than 5 percent, while
  vehicle miles traveled increased significantly.
• In a related effort, the use of reformulated
  gasolines has resulted in cleaner-burning
  engines.
• EPA and states continue to examine vehicle
  emissions-testing programs to ensure that
  readings accurately reflect emissions levels.

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The EPAs Efforts to Reduce NOx

• Emission standards for electric utilities
• To help reduce acid rain, EPA devised a
  two-phased strategy to cut NOx emissions from
  coal-fired power plants.
• The first phase, aimed to reduce NOx emissions by
  over 400 K tons per year between 1996 and 1999.
• The goal of the second phase is to reduce
  emissions by over 2 million tons per year
  beginning in the year 2000.
• NOx Transport rule for 22 States
• The CAA requires states to reduce ground-level
  ozone.
• Since NOx and ozone can be transported long
  distances, the Act also requires "upwind" states
  to implement programs that will help "downwind"
  states meet the ozone standards.
• EPA issued a rule in 1998 that requires 22 states
  and the District of Columbia to revise their
  Implementation Plans to further reduce NOx
  emissions by taking advantage of newer, cleaner
  control strategies.

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Rule 22 States
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SO2 What is it?

• Sulfur dioxide, or SO2, belongs to the family of
  sulfur oxide gases (SOx). 
• These gases dissolve easily in water. 
• S is prevalent in all raw materials, including
  crude oil, coal, and ore that contains common
  metals like aluminum, copper, zinc, lead, and
  iron. 
• SOx gases are formed when fuel containing sulfur
  (coal and oil) is burned when gasoline is
  extracted from oil or metals are extracted from
  ore. 
• SO2 dissolves in water vapor to form acid, and
  interacts with other gases and particles in the
  air to form sulfates and other products that can
  be harmful to people and their environment.

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SO2 Where does it come from?

• Over 65 of SO2 released to the air, or more than
  13 million tons per year, comes from electric
  utilities, especially those that burn coal. 
• Other sources of SO2 are industrial facilities
  that derive their products from raw materials
  like metallic ore, coal, and crude oil, or that
  burn coal or oil to produce process heat. 
• Examples are petroleum refineries, cement
  manufacturing, and metal processing facilities.
• Also, locomotives, large ships, and some nonroad
  diesel equipment currently burn high sulfur fuel
  and release SO2 emissions to the air in large
  quantities.

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SO2 Sources
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Causes for Concern

• SO2
• contributes to respiratory illness (children and
  elderly) and aggravates existing heart and lung
  diseases
• contributes to the formation of acid rain
• damages trees, crops, historic buildings, and
  monuments and
• makes soils, lakes, and streams acidic.
• contributes to the formation of atmospheric
  particles that cause visibility impairment, most
  noticeably in national parks.
• SO2 can be transported over long distances.
• SO2 and the pollutants formed from SO2 (sulfate
  particles) can be transported over long distances
  
• This means that problems with SO2 are not
  confined to areas where it is emitted.

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Health and Environmental Effects

• Respiratory Effects from Gaseous SO2
• Peak levels of SO2 in the air can cause temporary
  breathing difficulty for people with asthma who
  are active outdoors. 
• Longer-term exposures to high levels of SO2 gas
  and particles cause respiratory illness and
  aggravate existing heart disease.
• Respiratory Effects from Sulfate Particles
• SO2 reacts with other chemicals in the air to
  form tiny sulfate particles. 
• When these are breathed, they gather in the lungs
  and are associated with increased respiratory
  symptoms and disease, difficulty in breathing,
  and premature death.

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Health and Environmental Effects

• Visibility Impairment
• Haze occurs when light is scattered or absorbed
  by particles and gases in the air. 
• Sulfate particles are the major cause of reduced
  visibility in many parts of the U.S., including
  our national parks.
• Acid Rain
• SO2 and nitrogen oxides react with other
  substances in the air to form acids, which fall
  to earth as rain, fog, snow, or dry particles. 
• Some may be carried by the wind for hundreds of
  miles.

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Health and Environmental Effects

• Plant and Water Damage
• Acid rain damages forests and crops, changes the
  makeup of soil, and makes lakes and streams
  acidic and unsuitable for fish. 
• Continued exposure over a long time changes the
  natural variety of plants and animals in an
  ecosystem.
• Aesthetic Damage
• SO2 accelerates the decay of building materials
  and paints, including irreplaceable monuments,
  statues, and sculptures that are part of our
  nation's cultural heritage.

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The EPAs efforts in Reducing SO2

• Reducing acid rain
• SO2 is a primary contributor to the formation of
  acid rain, which is associated with acidification
  of soils, lakes, and streams, and accelerated
  corrosion of buildings and monuments.
• EPA is implementing a program to reduce releases
  of SO2 and other pollutants from coal-fired power
  plants. 
• The first phase began in 1995 for SO2 and targets
  the largest and highest emitting power plants. 
• The second phase (started in 2000) sets tighter
  restrictions on smaller coal-, gas-, and
  oil-fired plants. 
• Annual SO2 emissions will be reduced 10 million
  tons (almost half the 1980 level) between 1980
  and 2010.

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The EPAs efforts in Reducing SO2

• Reducing the formation of particulate matter
• Particulate matter can be formed from direct
  sources (like diesel exhaust or smoke), but can
  also be formed through chemical reactions.
• Emissions of SO2 can be chemically transformed
  into ammonium sulfates
• Very tiny particles that can be carried by winds
  100s of miles.
• These small particles have been shown to cause a
  series of health problems for asthmatics, the
  elderly, and other people with pre-existing
  respiratory problems.
• These same small particles are also a main
  pollutant that impairs visibility across large
  areas of the country, particularly national parks
  that are known for their scenic views. 
• Want to buy some SO2 emission allowances? 

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Lead What is it? Where does it come from?

• Lead- a metal found naturally in the environment
  as well as in manufactured products. 
• The major sources of lead emissions have
  historically been motor vehicles (such as cars
  and trucks) and industrial sources. 
• Due to the phase out of leaded gasoline, metals
  processing is the major source of lead emissions
  to the air today.
• The highest levels of lead in air are generally
  found near lead smelters.
• Other stationary sources are waste incinerators,
  utilities, and lead-acid battery manufacturers.

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Lead Where does it come from?
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Lead Chief Causes for Concern

• Children are at greatest risk
• Although overall blood lead levels have decreased
  since 1976, infants and young children still have
  the highest blood lead levels. 
• Can be exposed to through the air, and also
  through accidentally or intentionally eating soil
  or paint chips, as well as food or water
  contaminated with lead.
• High levels still of concern in localized areas
• Urban areas with high levels of traffic, trash
  incinerators, or other industry, as well as areas
  near lead smelters, battery plants, or industrial
  facilities that burn fuel, may still have high
  lead levels in air. 
• In 1999, ten areas of the country did not meet
  the national health-based air quality standards
  for lead.

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Health and Environmental Impacts

• Damages organs
• Lead causes damage to the kidneys, liver, brain
  and nerves, and other organs
• Exposure to lead may also lead to osteoporosis
  (brittle bone disease) and reproductive disorders
• Affects the brain and nerves
• Excessive exposure to lead causes seizures,
  mental retardation, behavioral disorders, memory
  problems, and mood changes
• Low levels of lead damage the brain and nerves in
  fetuses and young children, resulting in learning
  deficits and lowered IQ

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Health and Environmental Impacts

• Affects the heart and blood
• Lead exposure causes high blood pressure and
  increases heart disease, especially in men. 
• Lead exposure may also lead to anemia, or weak
  blood. 

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Health and Environmental Impacts

• Affects animals and plants
• Wild and domestic animals can ingest lead while
  grazing
• They experience the same kind of effects as
  people who are exposed to lead
• Low concentrations of lead can slow down
  vegetation growth near industrial facilities
• Affects fish
• Lead can enter water systems through runoff and
  from sewage and industrial waste streams
• Elevated levels of lead in the water can cause
  reproductive damage in some aquatic life and
  cause blood and neurological changes in fish and
  other animals that live there

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The EPAs Efforts to Reduce Lead

• Motor Vehicles
• In the early 1970s, EPA set national regulations
  to gradually reduce the lead content in gasoline
• In 1975, unleaded gasoline was introduced for
  motor vehicles equipped with catalytic converters
• EPA banned the use of leaded gasoline in highway
  vehicles in December 1995

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The EPAs Efforts to Reduce Lead

• Emissions from the transportation sector have
  dramatically declined (95 from 1980-1999)
• Levels of lead in the air have decreased by 94
  percent between 1980 and 1999. 
• Transportation sources, primarily airplanes, now
  contribute only 13 percent of lead emissions. 
• A recent National Health and Nutrition
  Examination Survey reported a 78 percent decrease
  in the levels of lead in people's blood between
  1976 and 1991. 
• This dramatic decline can be attributed to the
  move from leaded to unleaded gasoline

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The EPAs Efforts to Reduce Lead

• Industrial Sources
• Industrial processes, particularly primary and
  secondary lead smelters and battery
  manufacturers, are now responsible for most of
  lead emissions and all violations of the lead air
  quality standards
• Emissions from industrial processes have
  decreased by only 6 percent since 1988.  EPA's
  lead air quality monitoring strategy now focuses
  on areas surrounding these industrial sources

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Doe Run
La Oroya, Peru
Herculaneum, MO
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Similarities between La Oroya and Herculaneum

• Large lead smelting plant near populated area
• US has EPA
• Dangerously high lead levels in children
• 45 (2001)?17 (2003) Herculaneum, MO
• 99 (1999)?99 (2004) La Oroya, Peru
• Doe Run agreed to spend 140 million on pollution
  control between 1997 and 2007
• 32.4 million as of 2/2004
• More info

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O3 What is it? Where does it come from?

• Ozone (O3) is a gas composed of three oxygen
  atoms. 
• It is not usually emitted directly into the air,
  but at ground level is created by a chemical
  reaction between oxides of nitrogen (NOx) and
  volatile organic compounds (VOC) in the presence
  of heat and sunlight. 
• "Good" ozone occurs naturally in the stratosphere
  approximately 10 to 30 miles above the earth's
  surface and forms a layer that protects life on
  earth from the sun's harmful rays. 
• In the earth's lower atmosphere, ground-level
  ozone is considered "bad."

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O3 What is it? Where does it come from?

• VOC NOx Heat Sunlight Ozone
• Motor vehicle exhaust and industrial emissions,
  gasoline vapors, and chemical solvents are some
  of the major sources of NOx and VOC
• Sunlight and hot temps cause ground-level ozone
  to form in harmful concentrations in the air. 
• It is known as a summertime air pollutant. 
• Urban areas tend to have high levels of "bad"
  ozone,
• Rural areas are also subject to increased ozone
  levels because wind carries ozone and pollutants
  that form it 100s of miles away from their
  original sources.

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Chief Concerns

• Ground-level Ozone
• Triggers a variety of health problems even at
  very low levels
• May cause permanent lung damage after long-term
  exposure
• Damages plants and ecosystems
• The summertime pollutant
• Peak ozone levels typically occur during hot,
  dry, stagnant summertime conditions. 
• The length of the ozone season varies from one
  area of the United States to another. 
• Southern and Southwestern states may have an
  ozone season that lasts nearly the entire year.

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Chief Concerns

• Can be transported over long distances
• Ozone and the chemicals that react to form it can
  be carried hundreds of miles from their origins,
  causing air pollution over wide regions.
• Millions of Americans live in areas where ozone
  levels exceed EPA's health-based air quality
  standards
• Primarily in parts of the Northeast, the Lake
  Michigan area, parts of the Southeast,
  southeastern Texas, and parts of California.

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Chief Concerns
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Health Impacts

• Ozone can irritate lung airways and cause
  inflammation much like a sunburn.  
• Other symptoms include wheezing, coughing, pain
  when taking a deep breath, and breathing
  difficulties during exercise or outdoor
  activities.
• People with respiratory problems are most
  vulnerable, but even healthy people that are
  active outdoors can be affected when ozone levels
  are high.

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Health Impacts

• Repeated exposure to ozone pollution for several
  months may cause permanent lung damage. 
• Anyone who spends time outdoors in the summer is
  at risk, particularly children and other people
  who are active outdoors.
• Even at very low levels, ground-level ozone
  triggers a variety of health problems including
  aggravated asthma, reduced lung capacity, and
  increased susceptibility to respiratory illnesses
  like pneumonia and bronchitis.

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Environmental Impacts

• Plant and Ecosystem Damage
• Ground-level ozone interferes with the ability of
  plants to produce and store food, which makes
  them more susceptible to disease, insects, other
  pollutants, and harsh weather. 
• Ozone damages the leaves of trees and other
  plants, ruining the appearance of cities,
  national parks, and recreation areas.
• Ozone reduces crop and forest yields and
  increases plant vulnerability to disease, pests,
  and harsh weather.

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EPAs Efforts to Reduce Ozone

• Regional transport
• Although many cities have made efforts to control
  ozone by reducing local emissions, incoming ozone
  transported from upwind areas also needs to be
  addressed. 
• In 1998, EPA issued a rule that will
  significantly reduce regional emissions of
  nitrogen oxides (NOx) in 22 states and the
  District of Columbia, and in turn, reduce the
  regional transport of ozone.  Some regional
  strategies for reducing ground-level ozone
  include
• reducing NOx emissions from power plants and
  industrial combustion sources
• introducing low-emission cars and trucks
• using "cleaner" gasoline
• improving vehicle inspection programs

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Ozone
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Ozone