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					       Effects and Sources of Air
       Pollutants
                                                                        CE 524
                                                                        January 2011
Slides noted as AWMA are from: Understanding Air Quality from the Air
and Waste Management Association
Do not make copies of these slides for distribution
Major Provisions of 1970 CAAA
   Established NAAQS
        Primary – allows adequate margin of safety to protect public health
        Secondary – protects public from effects of air pollution
          • Plants, animals, visibility, public enjoyment of life & property
   Set new source performance standards for new stationary sources
   National Emission Standards for Hazardous Air Pollutants
    (NESHAPS) applied to existing and new plants
   Required states to submit state implementation plans (SIPs)
      Method to set AQ standards for air quality regions within state
       Definition of air pollution
   “Air pollution maybe defined as the
    presence in the outdoor and/or indoor
    atmosphere of one or more contaminants or
    combinations thereof in such quantities and
    of such duration as may be or may tend to
    be injurious to human, plant, or animal life,
    or property of which unreasonably interferes
    with the comfortable enjoyment of life or
    property or conduct of business.
Categories of air pollution

 Outdoor
 Indoor

 Occupational

 Personal exposure
    General classification of air
    pollutants
   Particulate matter
   SOx
   NOx
   Organic compounds
   CO
   Halogen compounds
   Radioactive compounds
   Photochemical oxidants
   Other inorganic compounds
        What about GHGs, ozone, biological agents?
Air Quality Criteria
   Based on levels to protect human health
       Sensitive members of the population

   Developed based on relationship between exposure and
    short and long-term health and welfare effects
   Effects are expected to occur when pollutant levels exceed
    criteria for specified time period
       Short-term -- immediate protection
       Chronic exposure

   Pollutant levels cannot legally be exceeded during specific
    time period in a specific geographical area
National Emission Standards
 Limit amount or concentration of pollutant
  emitted from a source
 Helps maintain or improve existing air
  quality in a region to meet state or local
  standards
 Based on what is achievable with current
  technology
Basis for Regional Standards
   Availability of technology
   Presence of monitoring stations
   Ability to enforce standards
   Understanding of synergistic effects of different
    pollutants
   Preparation of dispersion model (predicting
    ambient concentrations)
   Accurate estimates of growth or decline in
    industry or population
                                          • Carbon Monoxide (CO)

   Criteria                               • Hydrocarbons
   Air                                    • Oxides of Nitrogen (NOx)
   Pollutants                             • Sulfur Dioxide (SO2)

                                          • Particulate Matter (PM10)

                                          • Lead (Pb)


Fundamentals of Air Pollution and Motor Vehicle Emissions
John T. White, EPA
      Current NAAQS
 Pollutant   Averaging Time      Primary Standard   Secondary Standard
CO           8 hr                9 ppm              Same
             1 hr                35 ppm             Same
NO2          Annual average      0.05 ppm           None
SO2          Annual average      0.03 ppm           None
             24 hr               0.14 ppm           None
             3 hr                None               0.5 ppm
PM10         Annual arithmetic   50 g/m3           Same
             mean
             24 hr               150 g/m3          Same
PM2.5        Annual arithmetic   15 g/m3           Same
Added 1997   mean
             24 hr               150 g/m3          Same
Ozone        1 hr                0.12 ppm           Same

             8 hr                0.08 ppm           Same
Lead         3 months            1.5 g/m3          same
Hydrocarbons
   Result when fuel molecules in the engine do not
    burn or only partially burn
   React in the presence of nitrogen oxides and
    sunlight to form ground-level ozone, a major
    component of smog
   Ozone irritates the eyes, damages the lungs,
    and aggravates respiratory problems
       most widespread urban air pollution problem.
   A number of exhaust hydrocarbons are also
    toxic, with the potential to cause cancer.


                            Source: EPA 400-F-92-007 August 1994 Fact Sheet OMS-5
Particulate matter

 Dispersed airborne solid and liquid
  particles (specific size criteria in
  chapter)
 Settles out of air at rate which is
  function of size and weight (measured
  in micrometer µ = 10-4 cm)
 Dust, water vapor, etc
 Affect health and visibility
                                           • PM10 is a general term for tiny
                                                airborne particles (under ten
                                                microns), e.g., dust, soot, smoke
                                           • Primary sources are fuel-burning
Particulate                                   plants and other industrial/
                                              commercial processes
Matter                                     • Some are formed in the air
(PM10)                                     • They irritate the respiratory system
                                              and may also carry metals,
                                              sulfates, nitrates, etc.
                                           • Some overall decreases seen but
Also regulating                               trends may be masked by
                                              meteorological changes
PM2.5

 Fundamentals of Air Pollution and Motor Vehicle Emissions
 John T. White, EPA
Health Effects of PM

   Particles directly enter respiratory system
   Particles themselves may be toxic
   Particle may interfere with mechanisms
    which clear the respiratory tract
   Particle may act as carrier of absorbed toxic
    substance
       20 to 60% of particles between 1 and 2.5 µm
        breathed will penetrate into lungs
         • Enter deep tissue
                                • This term is used for a number of compounds
                                   containing sulfur
                                • Primarily caused by burning of coal, oil and various
    Sulfur                         industrial processes
                                • They can affect the respiratory system
    Dioxide                     • They react in the atmosphere to form acids, sulfates
                                   and sulfites
    (SO2)                       • Substantial reductions due to controls at the sources
                                   and through use of low sulfur fuels
                                    Make up 5 to 20% of total suspended particles

    Sulfur                          Major damage to materials
                                    Contributes to acid rain
    trioxide

Fundamentals of Air Pollution and Motor Vehicle Emissions
John T. White, EPA
                                          • Nitrogen dioxide is the prominent
                                             one (it's the yellow-brown color in
                                             smog)
   Oxides                                 • NOx results from high temperature
                                             combustion processes, e.g. cars
   of                                        and utilities
                                          • They affect the respiratory system
   Nitrogen                               • They play a major role in atmos-
   (NOx)                                     pheric reactions
                                          • Overall levels unchanged but
                                             transportation sources are cleaner




Fundamentals of Air Pollution and Motor Vehicle Emissions
John T. White, EPA
                                      • Odorless, colorless gas
                                      • Caused by incomplete combustion of fuel and
                                         air
   Carbon                             • Most of it comes from motor vehicles
   Monoxide                           • Reduces the transport of oxygen through the
                                         bloodstream
   (CO)                                  Poses immediate health risk in high
                                          concentrations (> 750 ppm)
                                         Hemoglobin has 240 times affinity for CO as
                                          for oxygen
                                      • Affects mental functions and visual acuity,
                                         even at low levels
                                      • Improvements are being made but there are
                                         still problems in some urban areas
Fundamentals of Air Pollution and Motor Vehicle Emissions
John T. White, EPA
                                          • Long known as one of the worst
                                             toxics in common use
                                          • Emitted from gasoline additives,
     Lead                                    battery factories and non-ferrous
                                             smelters
     (Pb)                                 • Affects various organs and can
                                             cause sterility and neurological
                                             impairment, e.g. retardation and
                                             behavioral disorders
                                          • Infants and children especially
                                              susceptible
                                          • Control of mobile sources has been
                                             exceptionally successful



Fundamentals of Air Pollution and Motor Vehicle Emissions
John T. White, EPA
                                          • Carbon dioxide
                                          • Chlorofluorocarbons
   Other                                  • Formaldehyde
   Air                                    • Benzene
   Pollutants                             • Asbestos
                                          • Manganese
                                          • Dioxins
                                          • Cadmium
                                          • Still others which are yet to be
                                             fully characterized
Fundamentals of Air Pollution and Motor Vehicle Emissions
John T. White, EPA
Categories of Air Pollution
   Ambient:
      air pollution in outdoors
        Focus of class
        Regulated by EPA
   Indoor
        Air pollution indoors, buildings
        EPA studies issues but no federal regulations
   Occupational
        Pollutants in the workplace (mining, chemical operations,
         etc)
        Regulated by OSHA
   Personal exposure
        Persons willful exposure
        Cigarette, gases, etc
Climate Change
                                           • Certain gases in the
                                              troposphere absorb some of
                                              the infrared radiation
                                              reflected from the earth
                                           • Carbon Dioxide is the major
                                              one (50%).
                                           • Others include methane
                                              (18%) and CFCs (14%).
                                              CFCs also are responsible
                                              for destroying the
                                              stratospheric ozone layer
                                           • The United States produces
                                              over 20% of the world's
                                              "greenhouse" gases
 Fundamentals of Air Pollution and Motor Vehicle Emissions
 John T. White, EPA
                                                                      Stationary
                                            Mobile Sources            Sources

       The
                  CO
       Extent
       of
                VOCs
       Air
                 NOx
       Pollution SO2
                   PM10
       Today
                                                    Lead
                                                            Overall, 54 million metric
                                                            tons from mobile sources
                                                            in 1990 (43% of total)
Fundamentals of Air Pollution and Motor Vehicle Emissions
John T. White, EPA
                                            63
                                                            Over 74 million people are
                                                            subjected to high levels of
  Who is                                                    at least one of these
                                                            pollutants
  Affected by
  Air                                               22               19

  Pollution?                                                 9
                                                                                   5
                                                                            1

                                       Ozone CO             NO2      PM10 SO2 Lead
                                             Millions of people living in counties with
                                             air quality that exceeds each NAAQS
                                             (1990 data)
Fundamentals of Air Pollution and Motor Vehicle Emissions
John T. White, EPA
World wide

 WHO indicates that 2.4 million people
  die from causes directly attributable to
  air pollution
 More than for car accidents
Visibility

 Although not a pollutant, visibility is a
  major pollution concern
 Haze

 Smog
Air Toxics

 Get information from EPA
 Example - http://epa.gov/otaq/toxics.htm
When is it a problem

 Classified as pollutant once their
  presence results in damage to
  humans, plants, animals or materials
 Concentration
     1 volume of gaseous pollutant = 1 ppm
     106 volumes (pollutant + air)


    0.0001 percent by volume = 1 ppm

				
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