Pollution — A Rising Environmental Problem

A is True and R is False.

Explanation
DDT was banned for agricultural use in India in 1972.
Currently, the sole consumer of DDT in India is the Ministry of Health and Family Welfare, which utilizes it to control vector-borne diseases by spraying it on walls in houses and buildings affected by malaria in both rural and urban areas.

A is True and R is False.

Explanation
Ozone is an allotropic form of oxygen. Chloroflurocarbons damage the ozone layer.

Both A and R are False.

Explanation
While nitrogen oxides and sulphur oxides contribute to air pollution and have various environmental impacts such as acid rain, they are not significant greenhouse gases. The primary greenhouse gases responsible for the greenhouse effect and global warming are carbon dioxide (CO₂), methane (CH₄) and nitrous oxide (N₂O).

(a) Pollution — Pollution is the addition of any such constituent to air, water or land which deteriorates the natural quality of the environment.

(b) Waste — Waste is any unwanted or undesired material or substance resulting from industrial, commercial mining, and agricultural operations, and from community activities.

(c) Air pollution — Air pollution means degradation of the air quality which harmfully affects the living organisms as well as certain objects.

(d) Oil spills — Oil spills are accidental discharges of petroleum in oceans or estuaries.

(e) Pesticides — Pesticides are substances used to kill, repel, or control certain forms of plant or animal life that are considered to be pests.

(f) Sanitary landfills — Sanitary landfills are the places where the wastes are dumped in a ground depression and covered with dirt every day.

(g) Noise — Noise is defined as any unpleasant/loud undesired sound interfering with one's hearing and concentration.

(a) Difference between sewage and effluents —

(b) Difference between biodegradable and non-biodegradable waste —

(c) Difference between smoke and smog —

Methane

Reason — Methane leads to retention of solar radiation in the atmosphere increasing the temperature.

Refrigeration equipment

Reason — Refrigeration equipment contain chlorofluorocarbons as cooling agent.

Sulphur dioxide

Reason — Sulphur dioxide reacts with water to form sulphuric acid causing acid rain.

Aerosols

Reason — Aerosols are responsible for causing the ozone hole.

Nylon

Reason — Nylon is non-biodegradable.

Recycling

Reason — One of the best solutions to get rid of non-biodegradable wastes is Recycling.

Pollution

Reason — An undesirable change in the environment is called as pollution.

Global warming

Reason — Global warming is caused due to greenhouse gases like carbon dioxide and methane.

Photon

Reason — The energy content of X-rays is usually measured in photon.

Iodine-131

Reason — Iodine-131 is radioactive pollutant which can cause thyroid cancer.

(i) False
Corrected statement — Pollutant are the agents that cause pollution.

(ii) True

(iii) True

(iv) True

(v) True

Four ways to control vehicular air pollution are:

1. Efficient engine
2. Good quality automobile fuels
3. Lead free petrol
4. Greater use of compressed natural gas

Two small scale industries that can be the source of particulate air pollution are:

1. Stone drilling
2. Brick kiln

1. Carbon dioxide (CO₂)
2. Sulphur dioxide (SO₂)

(i) False
Corrected statement — Liquid waste from kitchen, toilet and household constitutes sewage.

(ii) False
Corrected statement — Household detergents are not safe and are contributors to water pollution.

(iii) True

(iv) True

(v) False
Corrected statement — Hot water discharged into water bodies affects the fish and other aquatic life.

(i) True

(ii) False
Corrected statement — Fly-ash and metallic ash are examples of urban industrial waste.

(iii) False
Corrected statement — Chemical fertilisers may reach the rivers and harm the fish due to eutrophication.

(iv) True

(v) True

(vi) True

(vii) False
Corrected statement — Even though people working in noisy places may appear to adapt, long-term exposure to noise can still negatively impact their health, well-being, and productivity.

(i) False
Corrected statement — Diseases like cholera and jaundice are the results of water pollution.

(ii) True

(iii) True

(iv) True

(v) True

(i) Two major harmful effects of rivers contaminated with sewage are:

1. Sewage disposed of into rivers cause diseases such as diarrhoea, dysentery, cholera, typhoid, and jaundice.
2. The flora and fauna of rivers, sea and oceans is adversely affected.

(ii) Two major harmful effects of too much gaseous exhausts containing CO₂ and SO₂ are:

1. Excess emissions of CO₂ and SO₂ will increase the temperature of earth i.e global warming would increase.
2. SO₂ emissions would lead to severe lung and respiratory diseases.

(iii) Two major harmful effects of pesticides such as DDT used in agriculture are:

1. Pesticides kill soil microbes which are responsible to recycle the nutrients in the soil.
2. Pesticides can cause short-term adverse health effects, and can enter the food chain and affect the health of humans as well as animals.

(iv) Two major harmful effects of prolonged noise such as the one produced by crackers are:

1. Prolonged exposure to the high decibel noise damages eardrums and can bring permanent hearing impairment.
2. Interrupts concentration of thought and disturbs peace of mind.

Three major constituents of sewage are:

1. Kitchen wastes
2. Sanitary waste
3. Waste from agricultural lands

The common sources of oil spills are the overturned oil tankers, offshore oil mining and oil refineries.
Oil pollution kills a lot of marine life (fish, birds, etc.) The sea birds and sea animals sometimes get thick, greasy coating on their bodies due to oil spills.

Measures to minimise noise pollution are:

1. Prohibiting blowing of horns.
2. Restriction on loud speakers, specially during night.

'Swachh Bharat Abhiyan' is a significant cleanliness campaign started by the Government of India. It was officially launched on 2nd October 2014 with a dream of a clean and hygienic India. It emphasized upon people to neither litter nor let others litter. Millions of people from different sections of the society came forward and joined this mass movement of cleanliness. Following are some objectives of the campaign:

1. To clean the streets, roads and infrastructure of the country's cities and towns.
2. To eliminate open defecation through the construction of individual, cluster and community toilets.
3. To establish accountable mechanisms of monitoring latrine use
4. To achieve efficient solid and liquid waste management systems.

Two possible causes of the death of many fishes near a sea shore can be:

1. Industrial Waste — Large number of industries produces waste water which contains various types of chemical pollutants. Such wastes are commonly discharged into the rivers. These chemicals cause irritation to the body systems of fish.
2. Thermal Pollution — Many industries such as thermal power plants, oil refineries, nuclear plants use water for cooling their machinery. This hot waste water may be 8-10°C warmer than the intake water. This hot water is released into the nearby streams, rivers or the sea and causes warming. The sudden fluctuation in the temperature of water kills the fishes and harms the plant life growing in it.

(i) Noise Pollution

(ii) Industrial machines, workshops, trains, automobiles on the streets, jet aircrafts landing and taking off in the air, loud conversation and the radio or television inside houses, the loudspeakers and musical bands in public places, etc.

(iii) Two harmful effects of noise pollution are:

1. It lowers efficiency of work.
2. It disturbs sleep and leads to nervous irritability.

(i) The phenomenon depicted in the picture is Ozone layer depletion. It is a phenomenon in which certain gaseous compounds such as chlorofluorocarbons (CFCs) break down into chlorine atoms which in turn break down ozone (O₃) into oxygen (O₂) and O.

(ii) The sources responsible for ozone layer depletion are gaseous compounds such as chlorofluorocarbons (CFCs) released from refrigerators, aerosol spray cans and packaging material styrofoam.

(iii) Effects of ozone layer depletion on humans are:

1. Sun burn
2. Genetic disorders
3. Skin cancer

(i) This campaign was launched on 2nd October 2014.

(ii) Chief objectives of Swachh Bharat Abhiyan are:

1. To clean the streets, roads and infrastructure of the country's cities and towns.
2. To eliminate open defecation through the construction of individual, cluster and community toilets.
3. To establish accountable mechanisms of monitoring latrine use.
4. To achieve efficient solid and liquid waste management systems.

(a) Air pollution is shown in the figure. Air pollution means degradation of the air quality which harmfully affects the living organisms as well as certain objects.

(b) Two types of Air pollution are:

1. Gaseous pollution
2. Particulate pollution

(c) Gaseous pollution — The exhaust given out by vehicles is the source of gaseous pollution, e.g., cars or vehicles running on petrol or diesel.

Particulate pollution — The smoke released by the factory chimneys into the air are the main sources of particulate pollution, e.g., factory chimneys, brick kilns.

(d) Two ways to control air pollution are:

1. Use of unleaded petrol and CNG in automobiles.
2. Installation of tall chimneys in factories and fitting them with filters and electrostatic precipitators.

(a) Acid rain. Gases such as CO₂, SO₂ and oxides of nitrogen get dissolved in rain drops falling on the earth as rain. This constitutes acid rain.

(b) Four main sources of acid rain are:

1. Exhaust from vehicles contains CO₂, SO₂ and CO.
2. Smoke released by factory chimneys contain CO₂, SO₂ and oxides of nitrogen.
3. Burning of garbage releases CO₂ and other harmful gases.
4. Brick kilns produce ash which mixes with air to contribute to acid rain.

(c) Two harmful effects of acid rain on the living organisms are:

1. Damage to vegetation by pollution of the soil.
2. Fish and other aquatic organisms are harmed due to increased acidity of water in lakes and rivers.

(i) A - Biodegradable waste and B - Non-biodegradable waste

(ii) A

(iii) Recycling the materials into new products.

(i) CO₂ and SO₂

(ii) H₂SO₄ and HNO₃

(iii) Two harmful effects of acid rain

1. Damage to vegetation by pollution in soil.
2. Corrosion of buildings and monuments.

(i) SO₂

(ii) Bromochlorodifluoromethane and chlorofluoromethane.

(i) Rubber particles and dust raised by running motor vehicles are examples of particulate pollutants.

(ii) Too frequent exposure to X-ray in a medical diagnostic technique may damage chromosomes.

(iii) Thermal power plants give out a lot of hot waste water.

(iv) Sewage is a liquid waste from domestic activities.

(a) DDT — Dichloro-diphenyl-trichloroethane

(b) ODF — Open Defecation Free

(c) CFCs — Chlorofluorocarbons

(d) CNG — Compressed Natural gas

(e) LPG — Liquefied Petroleum Gas

(a) Dung, Leaves

(b) Plastics, Electronic waste

(c) Rubber particles, dust particles

(d) Carbon dioxide, Sulphur dioxide

(e) Iodine-131, Cobalt 60