Page 134 - Viva ICSE Science 5 : E-book

Biodegradable wastes: Waste materials
that can be easily broken down
(decomposed) by microorganisms

into simpler substances are called
biodegradable wastes. Such substances

become useful as they again get
utilised in nature (by mixing in the
Biodegradable wastes
soil). Examples of some biodegradable

wastes are peels of fruits and vegetables, parts of dead plants and animals, egg shells,
cloth and leather goods, excreta of humans and animals, wood and paper.

Non-biodegradable wastes: Waste materials that cannot be decomposed by
microorganisms are non-biodegradable

wastes. They remain on earth for many
years and harm the environment

Some examples of non-biodegradable

wastes are things made from plastics,
glasses, metals, electronic and medical
wastes, certain detergents, fertilisers
Non-biodegradable wastes
and pesticides.

Need for Proper Disposal of Biodegradable and
Non-biodegradable Wastes

Both types of wastes, if not disposed off properly, create problems.

When the biodegradable wastes decompose, they create bad smell. They attract fl ies,

cockroaches, mosquitoes and rats, which become carriers of germs and spread diseases.

Non-biodegradable wastes do not decompose and remain on earth for a long time.
They deplete the nutrients from soil and harm the growth of plants. Animals eat the

plastic bags and fall ill. They release poisonous chemicals which are harmful for air, soil
and water.

These chemicals pollute soil, air and water. Pollution of the environment is harmful for
all living beings.

Both types of wastes should not be burned at all as they release smoke and harmful

gases in the air.

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