Sources of Air Pollution

Air pollution consists of chemicals or particles in the air that can harm the health of humans, animals, and plants. It also damages buildings. Pollutants in the air take many forms. They can be gases, solid particles, or liquid droplets.

Sources of Air Pollution :

Air pollution can be caused by two sources: Natural and Man-made

Natural Sources :

Natural sources of pollution include dust carried by the wind from locations with very little or no green cover, gases released from the body processes of living beings (Carbon dioxide from humans during respiration, Methane from cattle during digestion, Oxygen from plants during Photosynthesis).

Natural Causes of Air Pollution are :

1. Winds and storms: Whenever there are strong winds and storms, huge amounts of dust and sand pollute the air. Pollutants can mobilize from the ground and transport them over large areas.

2. Explosions and Eruption of volcanoes: A volcano is an opening in the earth's crust through which lava, volcanic ash, gases disappear. Beneath a volcano, liquid magma containing dissolves gases rises through cracks in the Earth's crust. Volcanic eruptions emit a series of toxic gases as well as particulate matter but are usually restricted to localized areas. The release of harmful gases results in air pollution.

3. Forest fires: A forest fire is an unplanned, unwanted, uncontrolled fire in an area of combustible vegetation. Naturally occurring wildfires are most frequently caused by lighting. There are also volcanic, meteor, and coal seam fires, depending on the circumstance.Humans careless actions like cigarette or bidi, electric spark or any source of ignition when comes in contact with the dry vegetation results in forest fire. A huge amounts of smoke and ash are released into the air that causes air pollution.

4. Marshlands: A marsh is a type of wetland or an area of land where water covers the ground for a long period of time. A large amount of methane gas produced in these areas due to the activity of anaerobic microbes is also one of the main causes of pollution.

5. Pollen grains and fog: Pollen grains are microscopic structures that carry the male reproductive cell of plants. The release of a large number of pollen grains in the atmosphere causes conditions like pollen allergy in different organisms.

Fog is a visible aerosol consisting of tiny droplets or ice crystals suspended in the air at or near Earth's surface. Fog is one of the main causes of air pollution. Gases like sulfur dioxide, soot, and benzene, which form smoke react with the fog to form chemical compounds that form smog. Smog can cause eye irritation, coughing, difficulty breathing, congestion, and other respiratory problems.

Sample Questions

(More Questions for each concept available in Login)

Question : 1

Alina was asked to list the causes of air pollution. She made the follwing list A: Burning of coal B: Burning of Liquefied petroleum Gas C: Burning of compressed Natural Gas D: Occurance of ozone at low altitude Which are the correct causes in this list ?
A. Only A	B. A and B	C. A, B and C	D. All the four options
Right Option : D
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Question : 2

It said, the Tajmahal may be destroyed due to :
A. Flood in Yamuna river
B. Decomposition of marble as a result of high temperature
C. Air pollutants released from oil refinery of Mathura
D. All the above
Right Option : C
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Question : 3

Which of the following are correct : (a) Explosions and Eruption of volcanoes can cause air pollution. (b) A large amount of methane gas produced in Marshlands due to the activity of anaerobic microbes . (c) The release of a large number of pollen grains in the atmosphere causes conditions like pollen allergy in different organisms.
A. Only (a) and (b) are correct.		B. Only (b) and (c) are correct.
C. Only (a) and (c) are correct.		D. All of these.
Right Option : D
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