Not for Breathing Not for Drinking
What is Environmental Pollution ?
The environment is made up of living
and non-living components which are inter
dependent. When everything is working the
way it should be, all the components of the
environment will be functional, healthy and
balanced in the nature.
• What will happen if harmful organisms
or substances enter your body? How
do you feel?
In the same way if something harmful
is introduced into the environment and it
gets disrupted it can cause a chain of
problems affecting all the resources, plant
and animals life. These changes really hurt
the health and well being of living
organisms. Pollution therefore can be
described as the disturbance of
environmental balance caused by human
activities. It can also be caused by chemical
substances, biological species or by
dangerous radiations including sound and
heat.
Pollution is the addition to the
environment (air, water, land) of harmful
substances or energy in quantities that are
harmful to life.
What is Air pollution?
The composition of air in the
atmosphere comprises four major gases
namely nitrogen, oxygen, argon and carbon
dioxide. Other substances are present in a
very little amount and hence, they are
collectively known as trace components.
Air Pollutants:
As we discussed above, air pollutants
arise from both man made and natural
processes. These pollutants are of two
types : Primary and Secondary pollutants.
Pollutants are also defined as primary
pollutants resulting from combustion of
fuels and industrial operations and
secondary pollutants, those which are
produced due to reaction of primary
pollutants in the atmosphere.
Natural Activities:
• Forest fires release carbon particles
(ash) into the air and pollute the air.
• Volcanic eruption releases various
gases and ash into the atmosphere.
• Decay of organic matter releases
Ammonia gas into the air.
• Decay of organic matter lying under
water releases Methane gas.
• The pollen grains released by plants
remain suspended in the air and pollute
it.
Human activities
Burning fuels
Burning fuels pollute the air producing
pollutants like carbon monoxide, sulphur
dioxide, smoke, soot and ash.
• Name the fuels burnt in day to day
activities in both rural and urban areas.
Vehicles: Exhaust gases emitted by
motor vehicles pollute air by producing the
harmful pollutants like sulphur dioxide,
nitrogen dioxide, carbon monoxide,
unburnt hydrocarbons, lead compounds and
soot.
Industries: Various industries like
granite, lime, cement etc., pollute air by
releasing pollutants such as sulphur
dioxide, nitrous oxide, chlorine, fly ash ,
dust, asbestos dust etc.
• Name the factories located nearby. How
do they affect the air and water there?
Nuclear power plants: The two
problems of nuclear power are radioactive
waste and the possibility of disasters like
Chernobyl. Nuclear waste is dangerous
because it can cause cancer and other
health problems. The radioactive wastes
possess radio activity for at least one
million years. The other problems are melt
downs. Melt downs are provoked by too
much heat in the power plant. During a melt
down the power plant makes more
Radioactive pollution.
Chernobyl Disaster
The biggest meltdown of Nuclear
power reactor in the world was in
Chernobyl, Soviet Union in 1986. After the
melt down of chernobyl, there was an
explosion and formation of radioactive
cloud. The radiation released during this
disaster directly killed hundreds of people
and affected around 5 million more. About
125,000km2
of fields were unusable
because of the radioactive clouds. The
forest area was damaged by the radioactive
clouds.
Granite industries are in the most
polluted areas because granite powder,
cement dust, limestone dust is released
into the air causing pollution
are releasing the pollutants like
fly ash, Sulphur dioxide, and radioactive
substances causing the air, water and land
pollution. People are suffering from lung
cancer and skin allergies due to the
pollutionThe people living near the
granite factory have faced several health
problems like respiratory bronchitis and
asthma. Thermal power plants pollute air
by emitting sulphur dioxide, radio-active
substances and fly ash.
Power Generation Plants
There are a number of power generation
plants in our country. Some produce power
by using water (Hydroelectric power plants),
by using coal and gas (Thermal power plants),
by using Radioactive elements like Uranium
(Nuclear power plants). Electricity is also
produced from the air and tides of the
oceans. Ash dust and SO2 from the thermal
power plants are polluting the environment.
Deforestation: It is the destruction
of forests and woods. It has resulted in the
reduction of indigenous forests. Forests
now cover only 19% of the earth’s land
surface. Plants use carbon dioxide for the
process of photosynthesis. Due to lack of
forests the consentration of carbon dioxide
is increasing day by day resulting in global
warming. Discuss about the adverse effects
of Global warming?
Fertilizers and Pesticides: Use of
fertilizers and pesticides in agriculture
pollute not only air but also land and water.
You already learnt these issues in the
chapter ‘Production of food from plants’.
Chloro Flouro Carbons (CFC):
CFCs are used in refrigerators, Air
conditioners and aerosol sprays. Use of
CFCs pollutes air by depleting the ozone
layer as a result of which, harmful
ultraviolet rays reach the earth. What ill
effects do we suffer from exposure to UV
rays?
Mining: Mining of coal and stone
releases coal dust and stone dust that cause
air pollution.
What are the effects of air
pollution?
Air pollution continues to evoke a great
deal of interest worldwide due to its
negative impacts on human health and
welfare. It causes certain diseases including
shortness of breath, sore throat, chest pain,
nausea, asthma, bronchitis and lung cancer.
Extreme effects of air pollution include
high blood pressure and cardiovascular
problems.
The World Health Organization states
that 2.4 million people die each year from
causes directly attributable to air pollution
(WHO, 2007).
In addition to its negative health
impacts, air pollution is known to cause
injuries to animals, forests and vegetation,
and aquatic ecosystems.
Various harmful effects of
pollutants
Particulate Matter: Dust and smoke
spoil our cloths, reduce visibility and
affect the buildings; dust and smoke
get deposited on the leaves of the
plants. Thus affects the rate of
photosynthesis and transpiration. They
also cause Bronchitis, Asthma in
human beings. Particles of lead oxide
present in automobile exhaust can
cause Anaemia, Brain damage and even
death. Particles of mercury cause
Minimata disease which affect the
nervous system and can cause death.
Hydrogen Sulphide: Tarnishes silver
objects and blackens lead paints and
painting. It has a smell like Rotten
Eggs. It causes head ache in humans
when inhaled in a large quantity.
Carbon monoxide: It is a poisonous
gas. If it combines with haemoglobin
in our blood, it forms a stable
compound called carboxy
haemoglobin. Due to the formation of
this compound haemoglobin is unable
to carry oxygen to various parts of our
body. This leads to respiratory
problems. It causes suffocation and
may cause even death.
What can we do to reduce air
pollution?
Air pollution cannot be totally
eliminated, it can however be controlled.
Some of the methods for controlling air
pollutions are:
• Tall chimneys should be installed in
all factories to reduce air pollution
at the ground level.
• The 'Fuel burning equipment' which
burns the fuel completely should be
used in homes and industries.
• Install electrostatic precipitators in
the chimneys of industries.
• Reduce vehicular emissions by using
non polluting fuels like CNG.
• Use LPG for domestic use.
• Improve the quality of fuel in
automobiles and use catalytic
converters in them.
• Make use of Renewable alternative
source of energy like Solar Energy,
Wind Energy and Hydro Energy.
All motor vehicles should be
maintained properly so that they
comply with pollution norms.
Use unleaded petrol
Plant and grow more and more trees in
your surroundings.
Where is all of this pollution
coming from?
There are two main sources of water
pollution; definite and non-definite
sources.
Definite source pollution is due to
discharges from a single source, such as
an industrial site. It includes factories,
wastewater treatment facilities, septic
systems, and other sources that are clearly
discharging pollutants into water sources.
Non definite-source pollution involves
many small sources that combine to cause
significant pollution. For instance, the
movement of rain or irrigation water over
land picks up pollutants such as fertilizers,
herbicides and insecticides carries them
into rivers, lakes, reservoirs, coastal
waters, or groundwater. Non-definite
sources are more difficult to identify, as
they cannot be traced back to a particular
location. Landfills can also be a nondefinite source of pollution, if substances
leach from the landfill into water supplies.
Biodegradable waste: This consists
mainly of human and animal waste. The
biodegradable waste enters the water supply
and thus pollute the water. The waste
provides an energy source (organic carbon)
for bacteria. Organic carbon is converted
to carbon dioxide and water, which can
cause atmospheric pollution and acid rain;
this form of pollution is far more
widespread and problematic than other
forms of pollutants as a large supply of
organic matter in the water provides an
opportunity for oxygen-consuming
(aerobic) bacteria to multiply quickly,
consume all available oxygen, and kill all
aquatic life.
Sediment: It is one of the most
common sources of water pollution.
Sediment consists of mineral or organic
solid matter that is washed from land into
water sources. Sediment pollution is
difficult to identify, because it comes from
non-definite sources such as
constructional, agricultural, logging,
flooding, and city runoff. Sediment can
cause large problems, as it can clog
municipal water systems, smoother aquatic
life, and cause water to become
increasingly turbid. Turbid water can cause
thermal pollution, because it absorbs more
solar radiation.
Prevention And Controlling of
Water Pollution
Water pollution can be prevented or
minimized by adopting following
measures.
• Toxic industrial wastes should be treated
chemically to neutralize the harmful
substances present in it before
discharging into rivers and lakes.
• The sewage should not be dumped in to
the rivers directly. It should first be
treated at the sewage treatment plant to
remove the organic matter from it in the
form of manure.
• The use of excessive fertilizers and
pesticides should be avoided.
• The use of synthetic detergent should be
minimized or biodegradable detergents
should be used.
• Dead bodies of human beings and
animals should not be thrown in to rivers.
• The excreta and other garbage should be
treated in a biogas plant to get fuel as
well as manure.
• The water of rivers, streams, ponds and
lakes should be purified or cleaned. This
can be done both by the industries and
the govt. For example Ganga action plan
launched by the Indian Government.
• Trees and shrubs should be planted along
the banks of the rivers.
• There should be general awareness
among the masses regarding the harmful
effects of water pollution and the ways
of prevention. Waste paper, plastics,
waste food materials and rotten food and
vegetables should not be thrown in to
open drains.
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