Concepts of Air Pollution

1
AIR POLLUTION I
Characterization of Air Pollutants and Basic
Concept of Air Pollution

• Concepts of Air Pollution
• Components in air pollutants
• Global Warming
• Indoor Air Pollutants
• How to solve the problem?
• Conclusions

2
1. Basic Concept of Air Pollution

• Dilution is the only way to deal with air
  pollution. Some even develop into secondary
  pollutants by sun-light (ultraviolet). Methods
  must be employed to reduce the production of
  pollution rather than controlling the emissions.
• Air Emissions enter the sky and later become part
  of the precipitations (e.g. rain, snow, etc). For
  instance, acid rain was devastating in the 70s
  world-wide, and now in mainland China and Eastern
  Europe.
• Air pollutants eventually precipitate (snow or
  rain) to contaminate ground water, leaching into
  the waters (rivers, ponds, and coastal area).
  Ocean and rivers become the final sink. The
  pollutants are absorbed and accumulated via food
  chains to fish and birds.

3
1. Basic Concept of Air Pollution

• Air pollution includes air and particulate
  pollutants.
• Contaminated soil would affect the health of a
  forest, some trees might have become easier to be
  attacked by bacterial infections.
• Carbon dioxide and other green house airs from
  emissions from burning of fossil fuels cause
  global warming.
• CFCs are known to damage the earths ozone layer.
• Outdoor and indoor air pollution are both
  important.

4
1. Basic Concept of Air Pollution

• Outdoor pollutions are affected by climatic
  factors
• Seasons (e.g. precipitations),
• wind speed (dilution),
• sun-light (UV produces smog),
• Pressure (low pressure avoid pollutants to
  escape),
• Temperature (temperature inversions), etc.

5
Affected by landscape, city design (zoning), and
town planning.
???? Tunnel Effects
???? Wall Effects
6
Diseases related to air pollution

• Asthma (SO2 , particulates or any chemicals can
  induce complications of asthma patients)
• Bronchitis (all chemicals, RSP and NOx lower
  lungs immune response to microorganisms)
• Cardiovascular (CO, NOx affect pulmonary and
  circulatory systems)
• Discomfort (headache, stomach upset)
• Eye irritation (ozone or acidic response)
• Lung cancer (inhalation of diesel suspended
  particulates)

7
2. Components of air pollutants

• 50 carbon monoxide
• 16 sulfur oxides
• 15 volatile organic compounds
• 14 nitrogen oxides
• 5 suspended particulate matter
• (US data on a per weight basis, sources from
  USEPA cited in Miller, 1998)

8
2. Components of air pollutants
Where do they come from?

• Sources of Air PollutionNatural (volcanoes),
  Mobile (vehicles), andStationary (factory and
  power plants)

Mainly from burning of fossil fuels 49 from
transportation, 28 from combustion in stationary
sources, 13 from industrial processes, 3 from
solid waste disposal (incineration), 7
miscellaneous.
9
2. Components of air pollutants

• PRIMARY POLLUTANTS
• Emitted directly from sources such as burning of
  fossil fuels and factory emissions.
• CO, CO2
• SO2, NO
• HCs (hydrocarbons) or VOCs, such as volatile
  organic compounds, methane CH4, benzene C6H6,
  formaldehyde CH2O, CFCs (chlorofluorocarbons)
• SPM (suspended particulate matters or RSP)
• Radioactive substances, radon-222, plutonium-239
• Heat
• Heavy metal ions lead, cadmium, chromium, etc

10
2. Components of air pollutants

• Secondary Pollutants
• NO2
• SO3
• HNO2
• H2SO4
• H2O2
• O3
• PAHs (polyaromatic hydrocarbons)

Acid Rain
Photochemical Smog
Cancer causing culprits
11
2. Components of air pollutants
?????(????)
12
?????(????)
2. Components of air pollutants
13
Suspended Particulate Matters
2. Components of air pollutants

• TSP total suspended particulates
• Fine Particulates 0.001 to 1 micrometer
• Medium Particles 1 to 10 micrometer
• Large particles 10 to 100 micrometer

RSP

• Large particles (cannot get into respiratory
  tract)
• pollen, from flowering plants cause allergic
  responses.
• cement, from construction dust
• Coal dust, from burning of coal
• fly ash, from incinerators

14
Medium Particles 1 to 10 micrometer
2. Components of air pollutants
RSP, respirable suspended particulates

• Particulate matters PM 10, PM2.5, PM1
• Fly ash from incinerators
• Insecticide dusts
• Paint pigment
• Cement dust
• Coal dust from burning of coal
• Diesel engine exhausts

15
Fine particles
2. Components of air pollutants
RSP, respirable suspended particulates also
include

• 0.001 to 1 micrometer
• Carbon black
• Combustion nuclei
• Oil smoke
• Photochemical smog
• Tobacco smoke

16
3. Global Warming
17
Arctic perennial sea ice has been decreasing at a
rate of 9 per decade. Also the ice of frozen
freshwater on Greenland melts to dilute and lower
the salinity of the arctic ocean. This would have
significant effects (slower or stop) on the ocean
conveyor.
http//www.whoi.edu/institutes/occi/hottopics_clim
atechange.htm
Arctic 1979
Gulf Stream (Warm)
Arctic 2003
http//www.nasa.gov/centers/goddard/mpg/97515main_
SeaIceYrly.mpg
18
Carbon Cycle and Greenhouse Effect
19
Global Carbon Dioxide Surge leading to global
warming. ?????????????
Exceeding world records
20
Out of Control?
Kyoto Protocol
21
4. Indoor Air Pollution

• We spend more time indoor than in outdoor. For
  instance, 5 days week of work from 9 to 5 added
  up to be 40 hours. Over ten years work, we
  could be chronically affected by chemicals.
• Second hand smoke causes lung cancer.
• Kitchen and restaurant workers might have high
  risk.
• Occupational exposure should not be over-looked.

22
Indoor pollutants could cause acute diseases

• Legionnaires disease caused by bacterial
  infections from air-conditioners. It was first
  found in a conference for veterans.
• Other microorganisms including flu, molds and
  other infectious viruses could be dangerous.
• Sick building syndromes. You feel sick with
  headache and allergic symptoms like running nose
  and irritating eyes, but feel well after youve
  left the building.

23
TEN Major Indoor Air Pollutants

• Asbestos from tiles and pipe insulation.
• Benzene from solvent.
• Carbon monoxide from furnace.
• Formaldehyde (HCHO) from furniture, carpet and
  combustion appliances.
• Ozone (O3) from electrostatic devices,
  photocopiers, printers.

24
major indoor air pollutants (continued)

• 6. Radon-222 from granite.
• 7. Styrene from plastic or synthetic fiber.
• 8. Tetrachloroethylene from dry cleaning fluid.
• 9. Trichloroethane from aerosal sprays.
• 10. Tobacco smoke from cigarettes.

25
Radon is a known human lung carcinogen

• 13 of lung cancer deaths in Hong Kong might be
  related to radon. In US, about 15,000 lung cancer
  deaths each year might be related to radon.
• Smokers are at high risk (3 times over control)
  of having Radon induced lung cancer.

26
Solutions to Radon problem

• In Hong Kong, a survey done by EPD (1993) found
  that 5 of residential (829 premises), 10 of
  non-residential buildings had levels above the
  WHO guideline level of 200 Bq/m3.
• Ventilation may help to remove radon gas.
• Keep residence level a distance away from
  sources, e.g. granite. AT least two stories above
  ground for residence or offices.

27
5. How do we solve the problem??

• What did they do in other countries?
• Monitoring
• Set Objectives
• Legal actions
• Legislation/Ordinance/Law control Ban sources of
  exhaust producing chemical pollutants in air,
  e.g. reduce allowable sulfur content, lead
  content, ozone content, carbon monoxide content,
  etc.

28
(Adapted from EPD, 2001.)
29

• Lowered the limit of benzene content in petrol
  from 5 to 1 in April, 2000.
• ULSD (ultra low sulphur diesel introduced in
  July, 2000.
• LPG taxis to replace diesel taxis.
• Particulate trap retrofitting program to reduce
  emissions.
• Include emission test as part of the
  roadworthiness test for petrol vehicles.

(Adapted from EPD, 2001.)
30
CONCLUSIONS

• Chemical pollutions from air are harmful to our
  health.
• We must cut down the production of these
  chemicals in the air (indoor and outdoor).
• Urgent cases like CFCs, the chemical must be
  suspended, but substitute is needed.
• Other chemicals are targeted with clear
  objectives (guidelines).
• Monitoring, new targets, and legislative control
  must be taken.
• Many danger chemicals (e.g. dioxins) have been
  identified and we deal with them one by one.
• Cleaner fuel is needed, zero waste concept
  (renewable energy) is needed as well.
• Economic considerations, such as fuel taxes are
  useful.