Environmental Pollution – JSS3 Intermediate Science Lesson Note (First Term)

Pollution is the addition of harmful substances to the air, water or land that make the environment dirty, unhealthy or dangerous for living things.

Behavioural objectives

1. Define pollution and pollutant.
2. Name the four types of pollution.
3. State the causes and effects of each type of pollution.
4. Distinguish between biodegradable and non-biodegradable materials.
5. Explain ways of controlling pollution.

What is a pollutant?

A pollutant is any harmful substance or energy that is added to the environment and causes pollution.

• Smoke and fumes: from vehicles, generators and factories.
• Refuse: household waste dumped in gutters and streams.
• Chemicals and oil: from factories, farms and oil spills.
• Loud sound: a pollutant too, as in the buzzing of a generator outside your window.

What are the types of pollution?

There are four types of pollution: air pollution, water pollution, land (soil) pollution and noise pollution.

What is air pollution?

Air pollution is the entry of harmful gases, smoke or dust into the atmosphere.

Causes of air pollution

1. Smoke from car exhausts and factory chimneys.
2. Burning of bushes or refuse (trash).
3. Fumes from generators and kitchen stoves.
4. Dust from unpaved roads and construction sites.

Effects of air pollution

• Health problems: coughing, asthma and skin irritation.
• Global warming: on a big scale, polluted air makes the earth too hot.

What is water pollution?

Water pollution is the dumping of harmful substances into rivers, lakes, streams or oceans.

Causes of water pollution

1. Dumping household waste (trash) into gutters and streams.
2. Oil spills from big ships or broken pipes.
3. Chemicals from factories washed into rivers.
4. Using chemicals to fish, which is very dangerous.

Effects of water pollution

• Harm to water life: it kills fish and water plants.
• Diseases in humans: drinking polluted water can cause cholera, typhoid and dysentery.

What is land (soil) pollution?

Land pollution is the damage of the earth’s surface by waste and harmful substances, so that the soil loses its ability to grow food.

Causes of land pollution

1. Littering with non-biodegradable materials such as nylon bags and plastic bottles.
2. Using too many strong chemicals (fertilisers and pesticides) on farms.
3. Open defecation (passing faeces in the bush or on open land).

Effects of land pollution

• Ugly and smelly surroundings: the land looks dirty and smells bad.
• Loss of soil organisms: it kills helpful organisms such as earthworms.
• Poor crop growth: the soil cannot grow food well.

What is the difference between biodegradable and non-biodegradable waste?

Biodegradable waste is waste that rots and breaks down naturally. Non-biodegradable waste is waste that does not rot.

• Why “pure water” nylon is a problem: it does not rot, so it stays on the ground and in gutters.

What is noise pollution?

Noise pollution is any loud, disturbing sound that interferes with our peace or health.

Causes of noise pollution

1. Loud music from parties or religious houses at night.
2. Constant honking of car horns in traffic.
3. Heavy machinery and grinding machines.

Effects of noise pollution

• Headaches and stress: loud sound disturbs rest and sleep.
• Hearing loss: over time it can lead to partial deafness.

How can we control pollution?

Pollution is controlled by reducing waste, disposing of waste properly, planting trees and obeying laws that protect the environment.

The Three R’s

1. Reduce: buy only what you need so you have less trash.
2. Reuse: use an empty butter plastic to store pencils instead of throwing it away.
3. Recycle: turn old plastic and paper into new things.

Other control measures

• Proper waste disposal: use dustbins, and keep a central place in the community for waste collection instead of dumping in gutters.
• Afforestation: planting more trees. Trees are like the “lungs” of the earth because they take in carbon dioxide and give out oxygen, which helps clean the air.
• Laws: the government should punish factories that dump chemicals.
• Education: teach our neighbours why keeping the environment clean matters.
• Noise control: keep music at a low volume at night and switch off generators when not needed.

Evaluation

1. Define pollution and pollutant.
2. Name the four types of pollution and give one cause of each.
3. Why is it bad to throw “pure water” nylon on the ground?
4. Name three diseases caused by drinking polluted water.
5. Explain the Three R’s with one example each.

Assignment

Identify the four types of pollution in your neighbourhood. For each one, write one cause, one effect and one way to control it.