Introduction
Things around us make our environment. Living things get food, oxygen, water and other necessities of life from their environment. Environmental pollution is a big challenge to life. We should make serious efforts to reduce pollution in the environment. In this unit, we shall discuss kinds and sources of pollution. Effects of pollution and measures to reduce pollution also be discussed
Pollution and Pollutants
Environment is not always as clean as it should be. The human activities are mixing harmful substances in it. These harmful substances can be animal wastes, industrial wastes, ash, dust and smoke, etc. The addition of unwanted materials to the environment that make it unfit for life is called environmental pollution. The materials which pollute the environment are called pollutants.
Kinds of Pollution
Air, water and land are the parts of environment. Hence, pollution can be divided into following kinds:
1. Air pollution
2. Water pollution
3. Land pollution
Air Pollution
Air environment is being polluted by toxic materials present in traffic smoke and industrial smoke. These toxic materials are the major air pollutants. Road dust and burning of fuels in homes and furnaces are also polluting the air.
Activity
Hang a clean white tissue paper in open space.
Observe it after a day or two using a magnifying glass.
Can you see any materials attached with the tissue paper?
Where did these materials come from?
Water Pollution
We are adding sewage and industrial waste into rivers, canals, streams and oceans. In this way, we are polluting the water. Highly toxic materials present in industrial waste are the major cause of water pollution. The germs present in the sewage from hospitals and gutters are also water pollutants.
Land Pollution
We throw our domestic trash at open places on the land. This trash includes tin cans, plastic bags, rubbish and other solid wastes which pollute the land. Agricultural wastes, fertilizers, chemicals sprayed on crops and solid waste from factories are the main causes of land pollution.
Effects of Pollution
1. Air pollution causes diseases of throat, skin and eyes. Toxic air pollutants enter the human body with inhaled air and cause breathing difficulties, bronchitis and serious diseases like lungs cancer.
2. In plants, air pollution slows down the process of photosynthesis. It also reduces growth in plants.
3. Air pollutants released from industries dissolve in rain water and make it acidic . Acid rain damages trees, buildings and life in ponds and lakes, etc.
4. Polluted water affects the animals, plants and people who use it. Germs present in polluted water cause diseases like cholera, diarrhoea, typhoid, dysentery, etc.
5. Toxic matters like mercury, lead, chromium, arsenic etc. are present in industrial wastes which pollute the water and land environments. They cause serious diseases like cancer and brain damage.
6. Toxic chemicals and bacteria from the rubbish and other solid wastes when washed into rivers and oceans pollute water and harm the life in water.
7. Bacteria growing on raw sewage use much of the oxygen from water. Due to this reason, the fish and other aquatic life do not get enough oxygen and thus die.
Measures to Reduce Pollution
Following steps can be taken to reduce pollution:
1. Factories and industries should be shifted away from the cities;
2. Industrial wastes should be treated and made ineffective before releasing into the atmosphere.
3. Industrial waste and sewage should not be added into the fresh water of rivers or other water bodies
Domestic rubbish and other solid wastes should not be thrown into the streets or open places. They must be disposed off properly.
4. Measures should be taken to:
(a) reduce the number of vehicles on roads;
b) recycle the plastic wastes (cans, bottles and shopping bags);
c) reduce cutting of trees and forests as they absorb carbon dioxide and other air pollutants and reduce air pollution
d) Chlorofluorocarbons (CFCs) used in air conditioners, refrigerators or freezers if accidently released in the air will damage the protective ozone layer beyond the atmosphere on the Earth. This can lead to very serious consequences on human health. It is therefore important that alternate to CFC should be used to avoid damage to our Earth’s natural system.
Biodegradable and Non-Biodegradable Materials
Waste material or pollutants can be classified as biodegradable and nonbiodegradable. The materials which are naturally decomposed into simpler substances by natural process and mix in the soil for reuse by plants and animals are called biodegradable materials.
Kitchen waste, tree leaves, grass, wood, paper, cotton, leather, feathers, fruits, vegetables and dead organisms, etc. are the examples of biodegradable materials.
Non-biodegradable materials cannot be decomposed into simpler forms by natural process. Glass, ceramics, heavy metals, detergents, toxic chemicals, styrofoam, plastic bags and other plastic things are the examples of non-biodegradable materials.
Impact of Non-Biodegradable Materials on the Environment
Non-biodegradable wastes never decompose and remain as pollutants. Non-biodegradable pesticides and other toxic chemicals may cause diseases in animals and plants. Non-biodegradable materials cannot be recycled in the environment by natural process.
Ways to Reduce the Impact of Non-Biodegradable Materials
The three “3R” strategy (Reduce, Reuse and Recycle) is an easy way to control pollution due to non-biodegradable wastes.
1. Reduce
We must reduce the use of natural resources to produce plastic items and other non-biodegradable materials. We should stop using plastic bags for grocery, snacks and sandwiches, etc.
2. Reuse
The things which are made of non-biodegradable materials should be used again and again for various purposes instead of throwing them to increase pollution.
3. Recycle
The used plastic goods, broken glass bottles, and tin cans can be recycled easily. We should recycle them instead of throwing them as waste. Environmental pollution is a serious threat to life and we must share our responsibility to make our environment pollution free. You have learnt many ways to reduce pollution. However, you can conduct the following activities under the guidance of your teacher.
Activity
Create awareness in your community about environmental pollution, effects of pollution and minimizing pollution through seminars, banners and mutual discussions.
Develop an approach in your community to reduce using plastic bags, and plastic bottled drinks.