Chapter 2: POLLUTION AND CONTROL
average human needs 12-15 times more air than food.
matter of size 2.5 microns or less causes greatest harm to
humans. These can’t be removed even by electrostatic
precipitators which remove 99% of all particulate
matter from exhaust of thermal power plants.
for cars that emit toxic fumes, the presence of catalytic
converters is essential. In these converters metals like
platinum – palladium, rhodium are present. These convert
the un-burnt hydrocarbons, carbon monoxide, and nitric
oxide into water, carbon dioxide and nitrogen gas.
unleaded petrol must be used otherwise the catalyst in
the converters are inactivated by lead.
lead is used as an anti knock agent for smooth
running of vehicles. The lead if inhaled then causes
damage to kidney, liver and development of red blood
clouded high rise buildings trap the warm air and thus
raise the temperature of the cities. These creates Urban
Fig 1: Urban heating effect
and steel industries produce blast furnace slag, steel
melting slag and fly ash. This is non biodegradable and
now it’s used by cement industry to make blended cement.
warming is the rise of temperature of the earth due to
absorption of long wave terrestrial radiation by
the green house gases. 3°c increase can lead to decrease
in precipitation by 10%. It will cause polar icecaps to
melt and flood the coastal areas. Coastal ecosystems like
swamps and marshes will be damaged. Rainfall may fluctuate
and grains may mature early leading to smaller grain size
and lower yield. Hurricanes, tornadoes may increase in
intensity. Temperate areas might lose soil moisture
lowering agricultural productivity.
to rise in water temperatures the smaller fishes are
migrating to other areas and the bigger fishes are
affected. Big fishes may become extinct affecting marine
ecosystem and livelihoods of fishermen.
UV radiations from the sun are of three categories – A, B,
C. UV- C radiations are the most damaging to humans.
Air Pollution - China and India
Although the deaths recorded due to outdoor air pollution is higher in China than India. The rate of growth of air pollution deaths and the deaths per lakh population is higher in India. So more people die here due to outdoor air pollution.
The indoor air pollution deaths mostly due to cooking from fossil fuels is also higher in India than China. The measures taken by India to reduce indoor air pollution related deaths like promotion of LPG and CNG for cooking has reduced the number of deaths.
However the deaths due to outdoor air pollution have only increased due to increase in cars, and power plants. India had set emission standard norms for power plants in 2015 but not 1 has implemented them fully.
Water pollution and control:
sewage water is released in the rivers the microbes use up
more oxygen for degradation as it’s oxygen requiring
process. This increases the biochemical oxygen demand. The
oxygen isn’t available for aquatic animals and plants and
hence they die.
excess nutrients are present in soil the planktonic
organisms bloom and hence the competition for fishes and
other plants increase. This leads to algal bloom and fish
mortality. The water quality also deteriorates. This is
algal weed named water hyacinth is known as the terror of
Bengal for its fast growing rate.
of photosynthesis i.e. Penetration of sunlight below
the ocean surface is 125m.
Fig 2: Light and ocean
pollution is caused when the heated water released by
thermal, nuclear, chemical industries is released into
river, seas and oceans. The aquatic animals are suited to
a constant temperature and when the temperature increases
above a range it affects them. The hot water increases
their metabolism and affects their growth.
Mosquito borne diseases related
– female anopheles mosquito
– Culex mosquito
– Aedes Aeqypti
International drinking standards
the concentration of fluorine in water should be 1 ppm.
This converts the hydroxyapatite on the surface of the
teeth into flourapatite thus hardening them.
the concentration should e 50 ppm otherwise it will
<500 ppm otherwise it has laxative effect.
<50 ppm otherwise causes blue baby syndrome or Methemoglobinemia.
disease caused due to mercury poisoning as high
quantity of mercury was released in water.
– Itai disease is caused by cadmium poisoning. Lead
lung disease or pneumoconiosis is due to deposits of
coal in lungs of miners.
85% of Indian population depends
on ground water for its domestic consumption.
is a form of energy travelling through space.
electro-magnetic waves with long wavelengths that
have energy to excite the electrons to vibrate faster but
not to ionize them.
of short wavelengths and cause ionizing of water
molecules. These break the chemical bonds and damage
damage can be somatic or genetic. Somatic doesn’t affect
genes or mutation. Genetic affects genes resulting in
birth defects. These are passed on to the next
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