2. Definition – Air pollution
Air pollution may be defined as the presence
one or more contaminants or combinations
thereof in air in such quantities and of such
durations as may be or tend to be injurious to
human, animal or plant life, or property, or
which unreasonably interferes with the
comfortable enjoyment of life or property or
conduct of business.
3. Air pollutant
It is a substance or effect dwelling temporarily or
permanently in the air , which adversely alters the
environment by interfering with the health, the
comfort, or the food chain, or by interfering with
the property values of people.
A pollutant can be solid (large or sub-molecular),
liquid or gas .
4. Air pollutant classification
• Gases -
compounds of
Sulphur,
nitrogen, carbon,
oxygen etc.
• Natural
contaminants-
• Pollen particles,
bacteria's
• Aerosols-
• Dust, smoke,
mist, fumes,
fogs
5. Sources of Air pollution
Air Pollution may originate from a natural or
anthropogenic source or from both sources.
E.g. of natural source – an erupting volcano,
accidental fire etc.
6. Man made sources
Man made
sources
Stationary
sources
Point
sources
Industry,
Power plants
Fuel
combustio
n
Area
sources
Incineration,
residential,
industrial
estates
Rail yard,
ports,
Mobile
sources
Line
sources
Highways,
railroads
7. Percentage of Manmade
Pollution
Source CO (%) SO₂ (%) HC(%) NO – Nox
(%)
TRANSPORTATIO
N
92 4 65 42
INDUSTRIES 4 32 26 21
POWER PLANTS - 48 - 32
SPACE HEATING 3 12 3 5
COMBUSTION 1 4 6 0
8. Industrial Sources
Liquid soap factory
Sulphuric Acid factory
Plastic industry
Acid manufacturing units
Phosphate fertilized industry
Inorganic chemical plants
Metal industry
Aluminum plants
9. Effects of air pollution
Air pollutant affecting plants are – sulphur
oxide, Fluoride component, Ozone, Chlorine,
Ammonia, herbicides, smog etc.
Forms of damage to the leaves –
1. Necrosis
2. Chlorosis
3. Abscission
4. Epinasty
10. Dosage of air pollutant on Plants
Pollutant Dose Effect
1. Sulphur oxide Mild Interveinal chloriotic
bleaching of leaves
Sulphur oxide Severe Necrosis in interveinal areas
.
2. Ozone Mild Flakes on upper surfaces,
premature aging and
suppressed growth.
Ozone Severe Collapse of leaf, necrosis,
bleaching
3. Fluorides Cumulative
effect
Necrosis at leaf tip.
4. Nitrogen oxide Mild Suppressed growth , leaf
bleaching
5. Ethylene Mild Epinasty, Leaf abscission
11. Economic losses -methods
Building Materials- corroded and
disfigured by air pollutant by number of
way.
Abrasion
Chemical reaction
Adsorption
Corrosion
Deposition and removal
12. Effects on materials
Material effects Pollutant for exposure
Metals Loss of luster SO₂ , NO - NOx
Paints Discoloration SO₂ ,H₂S, SPM
Leather Bad gloss with no shine SO₂, CO₂
Paper Increase brittleness SO₂, CO₂, H₂S
Textile Decreases durability SO₂, CO₂
Dyes Bleaching action NO₂, CL₂,H₂S
Rubber Cracks, fatigue O₃, CO₂, CO
13. Effects on Human body
Major Air Pollutant Effect
CO ( carbon Mono-oxide) Interferes the bloods ability to carry oxygen
(by combining with hemoglobin) to heart,
brain, tissues
Fatal for heart patient and new born babies
High dose – leads to Coma
Mild dose – headache & tiredness
O₃ (Ozone) Reacts with lung tissues, cause harmful
changes in breathing passage, decreases
lung working ability and cause cough & chest
pain.
Cause eye & throat irritation
SO₂ ( Sulfur Di Oxide) It constricts air passage, creates asthma and
breathing problem in children.
SPM ( Suspended
particulate Matter)
Smaller particles are inhaled and settled in
lungs leading to breathing problem and lung
cancer
14. Continued…….
Major Air Pollutant Effect
Pb ( Lead) Damage blood, brain , nerves, kidney,
reproductive organs, and immunity system
No₂, NO ( oxides of
Nitrogen)
Respiratory Pathogens increase,
Eye, throat, lung irritation
PAN (Peroxy acetyl Nitrate) Eye irritation, burning, sneezing, cough and
cold.
15. Health Effects of Nitrogen
Oxides
Short-term exposure at concentrations greater
than 3 parts per million (ppm) can measurably
decrease lung function.
Concentrations less than 3 ppm can irritate
lungs.
Concentrations as low as 0.1 ppm cause lung
irritation and measurable decreases in lung
function in asthmatics.
Long-term lower level exposures can destroy
lung tissue, leading to emphysema.
Children may also be especially sensitive to
the effects of nitrogen oxides
16. Sulfur Dioxide
Ninety-five percent of pollution related sulfur
oxide emissions are in the form of sulfur dioxide
(SO2), a heavy, colorless gas with an odor like a
struck match.
Sulfur dioxide not only has a bad odor, it can
irritate the respiratory system.
Exposure to high concentrations for short periods
of time can constrict the bronchi and increase
mucous flow, making breathing difficult.
Children, the elderly, those with chronic lung
disease, and asthmatics are especially
susceptible to these effects.
