Effects of Pollution

Choose the correct option

Question 1

What is the effect of 150 dB of noise?

1. Pain in ear
2. Significant change in pulse rate
3. Permanent damage to hearing
4. Nausea, vomiting, dizziness

Answer

Significant change in pulse rate

Question 2

Birds avoid migrating to places where noise level is above ................. .

1. 100 dB
2. 90 dB
3. 150 dB
4. 140 dB

Answer

100 dB

Question 3

The process of depletion of oxygen from water bodies occurring either naturally or due to human activities.

1. Biomagnification
2. Eutrophication
3. Bioaccumulation
4. Pollution

Answer

Eutrophication

Question 4

The increase in the concentration of various toxic substances along the food chain:

1. Biomagnification
2. Eutrophication
3. Bioaccumulation
4. Pollution

Answer

Biomagnification

Question 5

The phenomenon of concentrated toxic deposition at the higher trophic level is known as:

1. Biomagnification
2. Eutrophication
3. Bioaccumulation
4. Pollution

Answer

Bioaccumulation

Question 6

Name the disease which resulted in numbness of body parts, vision and hearing problems and abnormal mental behaviour in Japan.

1. Corona Virus
2. Minamata
3. Encephalitis
4. Fluorosis

Answer

Minamata

Question 7

In Japan, pollution by heavy metal, cadmium, caused the disease called ................. .

1. Itai-itai
2. Minamata
3. Encephalitis
4. Fluorosis

Answer

Itai-itai

Question 8

Which disease causes discolouring of dental enamel and black and brown stains on the teeth?

1. Itai-itai
2. Minamata
3. Encephalitis
4. Fluorosis

Answer

Fluorosis

Short Answer Questions

Question 1

How does noise pollution affect animals?

Answer

Noise from industries, railways, crackers, explosions and commotion in the cities and aircraft, affect animals, birds, mice, fishes and domestic animals in the following ways-

1. Birds avoid migrating to places where noise level is above 100 dB.
2. The noise emissions caused by supersonic aircraft and railways may cause miscarriage in mammals and fishes as well.
3. Some of the birds have been found to have stopped laying eggs due to noise pollution.

Question 2

What major harm is done to human beings by air pollution?

Answer

Major harm done to human beings by air pollution are-

1. Chronic respiratory diseases
2. Lung cancer
3. Cardiovascular diseases and coma
4. Damage to the nerves, brain, liver, kidney etc.

Question 3

How are animals affected by air pollution?

Answer

Animals that feed on grass and plants, coated with polluted particulate matter, are affected with arsenic poisoning. Lead poisoning results in bronchitis and lack of appetite in pet animals.

Question 4

What is the effect of oil spills on marine life?

Answer

Sea water polluted with crude oil leakage causes oil spills which contaminate sea water and lead to the death of marine organisms.

Oil spills kill marine mammals such as whales, dolphins, seals, and sea otters. Oil can clog blow holes of whales and dolphins, making it impossible for them to breathe properly and disrupting their ability to communicate. Oil coats the fur of otters and seals, leaving them vulnerable to hypothermia.

Question 5

What causes waterborne diseases? Name two waterborne diseases.

Answer

Most of the waste waters especially sewage contain pathogens like bacteria, viruses and protozoa. These pathogens enter the human body from contaminated drinking water and are responsible for several waterborne diseases like cholera, typhoid etc.

Question 6

In what way does soil pollution affect human beings?

Answer

Soil pollution affects human beings in the following ways-

1. Soil contains many pathogenic bacteria, viruses and intestinal worms which are transmitted to man by the consumption of fruits and vegetables. These pathogens cause various types of diseases.
2. Radioactive fallout on vegetation is the source of radioisotopes which enter the food chain through the grazing animals. Some of these radioisotopes cause abnormalities.
3. Use of animals and human excreta as manure pollutes the soil. Excreta contains pathogens that contaminate the soil and vegetable crops and affect the health of human beings.

Question 7

Give the impact of radiations on human body.

Answer

Radiations affect living organisms. They cause harmful changes in the body cells and at genetic level. Some impacts of radiations on human body are-

1. Genetic variations — The damage caused by radiations is often seen in the offsprings and may be transmitted to many generations.
2. Somatic variations — Short term exposures to radiation can cause damage to organs of the body. The harm done by them includes breast cancer, thyroid cancer, lung cancer and brain cancer, sterility and defective eyesight.

Question 8

Why are nuclear radiations more dangerous than other forms of pollution?

Answer

Nuclear radiations are more dangerous than other forms of pollution because the high level products of nuclear wastes remain in the environment for several hundred years.

Structured Questions

Question 1(a)

State briefly how is noise pollution detrimental to human health.

Answer

Noise pollution is detrimental to human health because of the following effects-

1. Effect on hearing or deafness — Continuous exposure to noise levels above 100 dB has an adverse effect on hearing ability within a fairly short time.
2. Effect on Communication — External sounds can interfere with communication at important places like schools and offices. It also effects the use of radio and television.
3. Interference with sleep — Noisy conditions near residential areas at night cause difficulties in sleeping.
4. Mental or Physiological effects — Even short exposure to noise in excess of about 100 dB can lead to mental illness, cardiovascular diseases, stomach ulcers, respiratory disorders, headache and dizziness. It effects the foetus as well.
5. Effects on physical health and psychological problems — Exposure to noise in excess of about 100 dB can cause damage to inner ear. It also leads to problems like speech interference, annoyance, fatigue,sleep interference and emotional distress.

Question 1(b)

How does air pollution affect human beings?

Answer

The short term effects are-

1. irritation in the eyes, nose and throat
2. respiratory infections like bronchitis, pneumonia
3. headaches, nausea, vomiting, dizziness, convulsions and allergic reactions

The long term effects are-

1. Chronic respiratory diseases
2. Lung cancer
3. Cardiovascular diseases and coma
4. Damage to the nerves, brain, liver, kidney etc.

Question 1(c)

Explain how the accumulation of nutrients and chemicals in the water prove fatal for the marine organisms.

Answer

The accumulation of nutrients and chemicals in the water proves fatal for the marine organisms as the nutrient accumulation results in phenomenal growth of phytoplankton and algae, thereby reducing the penetration of oxygen, light and heat into the water body. As a result, most of the organisms die, draining water of all its oxygen.

Question 1(d)

With the help of a well labelled diagram explain how the accumulation of toxic substances increases as we move up the food chain.

Answer

Below diagram shows the increase in accumulation of toxic substances as we move up the food chain:

Biomagnification means increasing the concentration of various toxic substances along the food chain. Toxic substances at the level of primary producers get concentrated at each trophic level as they move up the food chain. The phenomenon of concentrated toxic deposition at the higher trophic level is known as bioaccumulation.

For example, if there are traces of toxic chemicals in water, then their concentration in algae will be much higher. When fish eat the algae, the concentration of toxins will increase further. Therefore, accumulation of a small amount of toxic chemicals in water can have a serious impact on the fish that live in it.

Question 2(a)

State any two effects each of soil pollution on human beings and environment.

Answer

Effects of soil pollution on human beings are -

1. Soil contains many pathogenic bacteria, viruses and intestinal worms which are transmitted to man by the consumption of fruits and vegetables. These pathogens cause various types of diseases.
2. Radioactive fallout on vegetation is the source of radioisotopes which enter the food chain through the grazing animals. Some of these radioisotopes cause abnormalities.

Effects of soil pollution on environment are-

1. Nitrogenous fertilisers produce toxic concentration of nitrate and nitrite in the leaves.
2. Land and soil pollution is responsible for loss of fertility and productivity of soil.

Question 2(b)

Name three common air pollutants and their effects on human health.

Answer

Question 2(c)

What are pathogens? How do they enter human body? Name any three diseases caused by these pathogens.

Answer

Pathogens are disease causing organisms like bacteria, viruses and protozoa.

Most of the waste waters especially sewage contain pathogens like bacteria, viruses and protozoa. These pathogens enter the human body from contaminated drinking water and are responsible for several waterborne diseases like cholera, typhoid, diarrhoea, dysentery etc.

Question 2(d)

State with examples the effects of radiations on the human beings and environment.

Answer

Example of radioactive accident

There was a radioactive accident in 1986 in Chernobyl in the Ukraine. On 26th April, 1986, a reactor at the nuclear power complex at Chernobyl exploded.

There was a massive steam explosion. The core of the reactor combined with water to produce hydrogen which exploded blowing toxic radioactive gases into the air. There were numerous fires. The Chernobyl accident is considered as the most disastrous nuclear power plant accident, both in terms of cost and casualties.

Due to the accident, 237 people suffered from acute radiation sickness, of whom 31 died within the first three months. After the disaster, four square kilometers of pine forest near the reactor turned reddish brown and died, earning the name of the 'Red Forest'. Some animals in the worst hit areas died or stopped reproducing.

Effects of radiations on human health

Radiations affect living organisms. They cause harmful changes in the body cells and at genetic level. Some impacts of radiations on human body are-

1. Genetic variations — The damage caused by radiations is often seen in the offsprings and may be transmitted to many generations.
2. Somatic variations — Short term exposures to radiation can cause damage to organs of the body. The harm done by them includes breast cancer, thyroid cancer, lung cancer and brain cancer, sterility and defective eyesight.

Effects of radiations on the environment

Radiations emitting from radioactive materials and the disposal of radioactive wastes cause pollution and damage the environment.

The high level products of nuclear wastes remain in the environment for several hundred years. Other radioactive threats to the environment are the accidents connected with the activities of nuclear reactors, nuclear powered vessels and satellites etc.

Thinking Skills

Question 1

The apparent lack of concern for the effects of pollution seems to be the reason for not implementing plans to prevent pollution. Justify this statement with examples.

Answer

Some examples to support the statement that the apparent lack of concern for the effects of pollution seems to be the reason for not implementing plans to prevent pollution are:

1. Economic interests — Industries prioritize profits over environmental concerns, leading to resistance in implementing pollution prevention plans. For example, some factories may avoid investing in cleaner technologies to cut costs.
2. Limited awareness — Insufficient knowledge about pollution's harmful effects results in a lack of concern and demand for prevention measures. For instance, individuals may not fully understand the impact of air pollution on respiratory health.
3. Political priorities — Governments prioritize other issues, delaying or neglecting pollution prevention. This can result in delays or inadequate implementation of necessary plans.
4. Weak enforcement — Inadequate penalties and enforcement create a perception of impunity for polluters. This reduces the motivation for industries to comply with pollution prevention measures.
5. Public indifference — Lack of public concern and support hampers pressure on policymakers to take action.

Question 2

Which is the most visible affect of pollution on human beings in your city? What are the causes and possible remedies?

Answer

One of the most visible effects of pollution on human beings in my city is the deterioration of air quality. The main causes for the deterioration of air quality are:

1. Industrial emissions — This includes the burning of fossil fuels and release of pollutants into the air.
2. Vehicle emissions — Emissions from cars, trucks and motorcycles contribute significantly to air pollution.
3. Agricultural practices — Burning crop residues and the use of chemical fertilizers and pesticides add to the pollution.
4. Household pollution — This is due to the use of solid fuels like coal, wood and biomass for cooking and heating purposes.

The possible remedies to improve the quality of air are:

1. Transition to clean energy sources like solar and wind power to reduce dependence on fossil fuels.
2. Improve industrial practices by implementing stricter emission control measures and promoting cleaner production techniques.
3. Promote public transportation systems and encourage the adoption of electric vehicles to reduce vehicular emissions.
4. Encourage sustainable alternatives to crop residue burning, such as recycling for energy production or composting.
5. Raise awareness and promote behavioral changes in waste management and reduction of polluting substances.
6. Strengthen environmental regulations, ensure compliance, and impose penalties for violators.

Question 3

Northern India is enveloped in smog in the month of November. List the causes for the same.

Answer

Northern India is enveloped in smog in the month of November because of the following causes:

1. Crop Residue Burning — In Punjab and Haryana, farmers often burn crop residues after harvesting to prepare the fields for the next crop. This releases a significant amount of smoke and particulate matter into the air.
2. Stubble Burning — The burning of leftover crop residue in the fields is a common practice after rice harvesting and contributes to the smog problem in northern India.
3. Diwali Celebrations — Diwali is celebrated with fireworks and firecrackers, which releases a large amount of pollutants, including particulate matter and toxic chemicals into the atmosphere.
4. Industrial Emissions — The industrial activities and factories in the region release pollutants like sulphur dioxide, nitrogen dioxide and particulate matter into the air, contributing to the smog formation.
5. Vehicular Emissions — The high number of vehicles in the region contribute to air pollution through exhaust emissions.