Page 90 - ICSE Chemistry 6

• The use of RO purifi er should be minimised. The unused water from the RO purifi er should be
collected and used for household ac vi es.
• Sprinklers should not be used in the garden as they cause wastage of water. Schools and housing
socie es should be encouraged for rainwater harves ng.

Nature Care
Observe the consump on of water in your house. Now make a list of instances where you think water is being
wasted. Think of ways to conserve water in such instances.

WATER POLLUTION

The contamina on of water with unwanted substances that cause harmful eff ects in living and non-living
things is called water pollu on. Unwanted substances alter the proper es of water and make it unfi t for
drinking, bathing and agricultural use.
Causes of Water Pollution

Following are some main causes of water pollu on.
• Discharge of domes c sewage and dumping of a garbage
into water bodies pollutes them.
• Discharge of agricultural waste, which include fer lisers,
insec cides and pes cides containing poisonous pollutants
such as cyanide and mercury pollute water.

• Discharge of industrial waste like plas c, paints, drugs, paper,
tex le dyes, rubber and leather from various industries into
the nearby water bodies pollute water. Fig. 4.12: Water pollution
• Defeca on by human beings and animals in or near water bodies also pollutes water.
• Oil spill from oil tankers and leakage of oil during drilling and shipping opera ons pollute water. A
layer of oil is formed on the surface of the water which cuts off the supply of oxygen for organisms
living in the water body thereby causing their death.
• Waste from nuclear plants discharged directly into water bodies kill aqua c plants and animals,
and disturb the balance of nature.
Prevention of Water Pollution

Following measures should be taken to prevent water pollu on.
• Water treatment plants should be installed in all industrial areas.
• Sewage, agricultural and industrial wastes should be treated properly before being released into
water bodies.

• Proper toilet facili es should be provided to people.
• Use of environment-friendly household products such as washing powder, toiletries and household
cleaning agents should be encouraged.
• Limited use of fer lisers and pes cides, and use of eco-friendly fer lisers and biodegradable
pes cides should be promoted.
• Sources of underground water like well should be kept clean and covered.

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