Chapter 5
Environmental pollution
1. What is environmental pollution? Write about different types of pollution.
Answer: Environmental pollution is the undesirable change that occurs in our environment due to human activities. Pollution is an undesirable change in the physical, chemical and biological properties of air, water and soil – which causes damage to people, animals, other living things and property.
The different types of pollution are:
(a) Air pollution
(b) Waterpollution
(c) Soil pollution
Depending on the pollutant, pollution can be of the following types:
(a) Thermal pollution
(b) Noise pollution
(c) Radioactive pollution
(d) Soil waste pollution
(e) Oil pollution
(f) Industrial pollution
(g) Marine pollution
2. What is air pollution? Identify sources of air pollution .
Answer: Air pollution is the amount and duration of the presence of one or more harmful substances in the air that can be harmful to health and public welfare and also harm other animals or plants.
Sources of air pollution are:
1. Natural Sources-
(a) Volcanic eruptions
(b) Forest fires
(c) Natural and decomposition functions of organic and inorganic matter
(d) Dust
(e) Flower pollen
(f) Fungal spores
(g) Radioactive substances
2. Man-made sources
(a) Deforestation
(b) Smoke emissions from vehicles
3. State the effects of air pollution on the human body.
Answer:
4. The What is water pollution? What are the effects of air pollution on the human body?
Answer: Water pollution is the addition of unwanted substances to water that is harmful to humans, animals and aquatic animals.
The effects of water pollution on the human body are:
(a) Typhoid- Salmonella typhi
(b) Cholera- Vibrio cholerae
(c) Dysentery- sigella
(d) Diarrhea- Cryptosporidium
(E) Giardiasis- Giardia lamblia
(f) Diarrhea- e-coli
(g) Gastroenteritis- various viruses
(h) Polio- poliovirus.
5. What is land pollution? How can it be controlled?
Answer: Soil is polluted by various types of waste including domestic and industrial waste, pesticides used in agricultural land etc. The addition of various toxic substances reduces soil fertility and pollutes the soil. This is called land pollution.
Some of the land pollution control measures are:
(a) Industrial wastes should be thoroughly treated before discharge to land.
(b) Solid wastes should be divided into biodegradable and non biodegradable at source and decomposed by effective scientific methods.
(c) The use of organic fertilizers instead of chemical fertilizers should be encouraged.
(d) The use of chemical pesticides should be controlled.
(e) Bioremediation can be used to remove toxic chemicals from the soil
(f) Necessary laws should be introduced to take punitive action against those involved in land pollution.
(g) Awareness should be created among the people.
6. What is bulk trash? How are they classified? Give examples.
Answer: Solid waste is generated by domestic, commercial, institutional, agricultural, mining and industrial activities. Solid waste is waste that is discarded as unfit for use and unnecessary. This means that materials thrown in the wrong place are called solid waste.
7. Discuss the environmental impact of solid waste.
Answer: Solid waste causes various problems in the environment. They are:
- The garbage dump becomes contaminated, where rats and flies that carry diseases breed.
- Methane gas is released into the surrounding area due to the decomposition of solid waste by microorganisms.
- Wastewater from or flowing through solid waste eventually mixes with soil, open source water and groundwater.
- Aggregate waste contains a mixture of different materials and these are not separated at any stage. This waste includes various types of waste products generated from industry, hospitals, nursing, homes, household chores etc.
- Wastewater from landfills contains various chemicals and these pollute groundwater.
- The problem is exacerbated by the lack of concrete or other cover on the surface of the landfill.
- The health of the people living near the landfill is inevitable, it cannot be avoided.
- Currently, everyone goes from house to house to collect garbage, which is a waste of time and increases the cost of garbage collection.
- Open transportation of waste in tractors or trucks is unhealthy and also spoils the aesthetic beauty of the city.
8. Mention two methods for handling aggregate waste.
Answer:
9. What is noise pollution? Name two effects it can have on the human body.
Answer: Noise pollution, which has various harmful effects on the activities of human or animal life, is a vibration or wave caused by the collision of molecules, which comes through any medium and is felt by the ear.
Two effects of noise pollution on the human body are:
(a) Noise pollution gradually reduces hearing and eventually people become black or deaf.
(b) Difficulty in communication, boredom, anxiety, feeling stressed, irritability and aggressive behavior are caused by the hearing loss effects of noise pollution in the human body.
10. What measures can be taken to keep drinking water sources clean and safe ?
Answer: The measures to be taken to keep drinking water sources clean and safe are:
(a) Location: Water sources from toilets, sewers, garbage etc. should be located at an elevated place at a distance of at least 10 m to 15 m.
(b) Platform: A concrete platform or base about 1 m high should be erected around the tubewell and concrete well and drains should be constructed to prevent water from accumulating in this area. The concrete platform shall not be deformed or broken.
(c) Sewerage: Sewerage system near water source should be scientific to prevent accumulation of dirty water. Do not allow wastewater to accumulate in this area.
(d) Cover: The mouth of the concrete well should be closed with a lid to prevent the entry of any foreign materials or objects.
(e) Lining: To prevent outside dirty water and surrounding storage water from entering the concrete well, the bottom should be concreted with cement and stone for about six meters around the well.
