Transcript AIR POLLUTION - TEACHERS WEBSITE

AIR POLLUTION
Presented by
MOHD.ZAKIR ALI
VISAKHAPATNAM
ENVIRONMENT
 sum of all social, economical ,biological,
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physical or chemical factors which constitute
the surroundings of man who is both creator
and moulder is called environment.
Environment consists of
Abiotic
Biotic and
Energy components
SEGMENTS OF ENVIRONMENT

Atmosphere
the protective thick gaseous layers surrounding the earth
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Hydrosphere
It deals with water which includes sea, rivers, oceans,
lakes etc.
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Lithosphere
The solid components of the earth which includes soil,
rocks, and other nonliving things.
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Biosphere
It deals with living things present in atmosphere and
hydrosphere.
Types of Pollution
1.
2.
3.
4.
Air Pollution
Water pollution
Soil pollution
Sound pollution
COMPOSITION OF ATMOSPHERE
• The natural air consists of
N2
=
78.84%
O2
=
20.94%
CO2
=
0.03%
Ar.& others= 1%
Air pollution
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Direct or indirect introduction of any
material in to the atmosphere in an
amount that effects the quantity and
composition of the outside atmosphere
resulting in detrimental effect on human
beings and non-living things is called air
pollution
Air pollution is most important from
public point of view, because every
individual person breathes
approximately 22000 times a day
inhaling about 15 to 22 kgs of air daily.
The polluted air causes ill effects.
CAUSES OF AIR POLLUTION
NATURAL CAUSES
 Volcanic eruptions
 Burning of forests
 Storms
 Virus & bacteria
 Earthquakes
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MAN-MADE CAUSES
Increase in human
population
Rapid industrialization
Deforestation
Transportation services
Agricultural activities
Radioactive substances
INDUSTRIAL POLLUTION
INDUSTRIAL POLLUTION
VOLCANIC ERUPTION
LAVA
POLLUTANT
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The excess concentration any
unwanted gaseous substance present
in atmosphere that causes harmful
effect to the living and nonliving
things is called pollutant.
Classification of pollutants
1. primary pollutants
The substances which are produced at the source it
self and enters into the atmosphere directly.
co2, co, NOx, sox
2. Secondary pollutants.
The primary pollutants undergo chemical reaction in
presence of sun light and produce a new toxic
substances are called secondary pollutants
PAN,PBN and any photochemical smog.
Types of pollutants

Gaseous pollutants
CO, CO2, NOx, SOx, CFC’s, HF,
Hydrocarbons and all other vapours.
 Particulates
dust, smoke,
 Aerosols
mist, fog ,fumes & gases and smog
Effects of air pollution
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Carbon monoxide:
It combines with haemoglobin and forms
carboxyhaemoglobin which leads to death.
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It causes
headache, nausea, hard breathing, cardiovascular
disorders and lung cancer.
SULPHUR OXIDES
• It causes respiratory problems like bronchitis
• It causes chlorosis, necrosis, plasmolysis, and
retards growth of plants.
• It causes acid rains
• It causes corrosion of metals
Carbon dioxide:
It leads to rise in global warming.
due to which the icebergs melt
,water levels increases in oceans
and submerge cities Islands may
disappear
Nitrogen oxides
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These oxides form PAN and PBN by
undergoing chemical reaction in the
presence of sun light.
They lead to acid rains which damage crops
and structures and causes skin cancer, eye
irritation and asthma.
Effects of air pollution on plants
• Acid rain destroys crops and forests.
• SO2: it causes bleaching of leaves.
• NO2 : it causes bleaching of leaves and
reduced fruit production.
• HF: it damages the crops.
Effects of air pollution on property
 SO2:
it causes corrosion and damages
marble structures, eg., Tajmahal.
 NO2 & H2S: cause corrosion of buildings
and darkening of painted surfaces.
General effects air pollution
Green house effect
 Ozone depletion
 Acid rain
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DEPLETION OF OZONE LAYER
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The ozone layer is present in stratosphere which is extended
from 11 to 15 km from the surface of earth
It protects the living things from UV radiation
OZONE LAYER is depleted by various pollutants NOX, CFC’s
present in the atmosphere.
Due to depletion of ozone layer the UV radiation passes on to
the surface of the earth and it effects
1.Gobal temperature
2.Rate of photosynthesis
3.Causes skin diseases
Ozone is mainly broken down by chemicals called
Chlorofluorocarbons and also by nitrogen oxides. CFC's
ironically were first used in large quantities because they were
thought to be safe and inert (unreactive) chemicals. They are a
group of chemically similar gases used in refrigeration systems,
air conditioners, aerosols, solvents and in the production of
some types of packaging. Nitrogen oxides are a by-product of
fuel burning, e.g. aircraft exhausts.
CFC's don't occur naturally, they are man-made chemicals.
They are very useful when they are where they are supposed
to be, and doing what they are supposed to be doing. But once
released into the atmosphere they are a serious pollutants.
The actual reactions that destroy ozone are very complicated.
They take place on the surface of the ice particles of the Polar
Stratospheric Clouds and it takes only a small amount of
CFC to destroy an awful lot of ozone.
ionosphere
mesosphere
stratosphere
troposphere
Depletion of ozone
layer
EARTH
Control of air pollution
Air pollution can be controlled by
 Periodical checking of industrial machinery
 Periodical checking of automobile engines.
 Industrial zoning i.e., separation of
industries from cities & towns by forests.
 Reduction of smoke at source itself, such
as installing electrostatic precipitators,
etc.,
 By growing more trees