Air Pollution Causes
Table of Contents
Air pollution causes-
General Meaning and Definition of Air Pollution
Our Earth is covered by atmosphere from all sides.
The atmosphere is made up of a mixture of different gases.
These gases have a fixed proportion in the atmosphere.
Like- Nitrogen (78.08%), Oxygen (20.94%), Argon (0.934%), Carbon dioxide (0.032%) and Others (0.002%).
Due to various geographical reasons, these gases keep circulating on the surface in the form of air.
These atmospheric gases have a natural system to keep their quantity (fixed ratio) balanced,
but if due to some reasons the balance changes in their fixed ratio at any level, then this situation is called air pollution.
Environmentalists and various organizations have defined air pollution as per their own.
Some of these definitions are as follows:-
According to Hesketh,
“If the presence of such external elements in the air is harmful to human health or welfare, then this situation is called air pollution.”
Pro. According to Jagdish Singh,
“Air pollution refers to such unwanted changes in the physical, chemical and biological properties of air which have adverse effects on the living conditions of humans and other living beings.”
According to the World Health Organization (WHO),
Air pollution is a situation in which elements that harm humans and their environment get concentrated in a dense form in the external environment.
Common Forms Of Air Pollutants
Generally air pollutants are present in the atmosphere in the form of gaseous or vaporous particles.
The chemical vapors found in the atmosphere are produced from substances whose boiling point is 200°C.
The major air pollutants are as follows-
A. gases and chemical vapors
1. Oxide of carbon;
Like- carbon monoxide (CO), carbon dioxide (CO₂).
2. Oxides of nitrogen; Like- Nitric Oxide (NO), Nitrogen Dioxide (NO₂),
3. Oxides of Sulphur; Like- sulfur dioxide (SO₂). sulfur trioxide (SO)
1. Simple hydrocarbons.
2. Aliphatic-alkane; Like ethane, methane.
Alkene; Like ethene, propene. Alkyline; Like- acetylene.
3. Aromatic; Like- benzene, toluene,
B. Isolated particles
1. Solid particles such as; fragrant smoke,
2. Liquid particles like; Dust, smoke, fog, mist etc.
CAUSES OF AIR POLLUTION AND ITIS SOURCES
Generally we divide the causes or sources of air pollution into two categories:-
(a). Natural causes/sources,
(b), Human causes/sources.
Due to both these reasons/sources, two types of elements (gases and particulate matter) are released into the atmosphere.
These gases and particulate matter mix with the gases present in the atmosphere and spread pollution.
(A) Natural Causes-
The unbalanced behavior occurring in nature is the main cause of pollution.
To a great extent, man is responsible for this unbalanced behaviour.
Under these, pollutants arising from natural imbalance are included.
The main types of these are the following-
1. Forest fire:
Forest fire i.e. forest fire is also a reason for polluting the atmosphere of that particular area.
Due to this increase in temperature, excessive amount of smoke and ash particles pollute the atmosphere.
2. Biological decay of organic and inorganic substances:-
As a result of biological decomposition of dead organisms (animals and plants) various gases (H₂S, SO2, CH) are produced which promote air pollution.
3. Volcanic eruptions:-
There are more than 400 living volcanoes in the world.
These volcanoes continuously produce dust, ash particles, carbon monoxide (CO), sulfur dioxide (SO₂), other poisonous gases, particles of solid metals, lava etc.
which reach the atmosphere and contaminate it.
(B) Human Causes:-
In the present era, compared to natural causes, human causes/sources are more prominent in air pollution.
As human activities and activities are increasing, accordingly there is a huge increase in pollutants, air pollution is also a side effect of this.
For example –
(1) Combustion process: –
Burning of a substance in the presence of air is called combustion.
By combustion of various substances, various types of gases, smoke, ash etc.
are produced which pollute the atmosphere.
Combustion process is done in the following areas-
(i) Combustion in automobiles –
Moving vehicles like trucks, buses, scooters, cars, airplanes, etc.
run on petrol or diesel.
Carbon monoxide (77.2%), nitrogen oxide (7.7%), and other hydrocarbons (13.7%) produced as a result of combustion of fuel (petrol, diesel)
at various stages in the engines of these vehicles, spread into the atmosphere and pollute it.
Along with these gases, metal particles like lead are also released.
(ii) Combustion in domestic work:-
Since ancient times, traditional fuels like wood, coal, kerosene, coal have been burnt every day in domestic works like cooking food, heating water, etc.
Their combustion produces large amounts of carbon dioxide, carbon monoxide, sulfur dioxide, nitrogen oxides and organic particles
which get discharged into the atmosphere and contaminate it.
Combustion of LPG (Liquid Petroleum Gas) used in the kitchen also produces toxic gases like nitrogen monoxide and nitrogen dioxide.
(iii) Combustion in thermal power stations: –
In India, electricity generation is mainly done by burning coal.
It is a source of air pollution.
Burning of coal in thermal power plants produces carbon dioxide, oxides of sulfur and other gases, which causes air pollution and its side effects.
(2) Production units of various industrial establishments :-
In the present industrial era, all nations are trying to surpass each other.
For this reason, big industrial cities have been established in all the countries.
Every day, a large amount of toxic gases like CO, SO2, NO, H₂S and particles of other waste materials get released into the atmosphere from the production units of these industries.
Due to which the atmosphere is becoming polluted.
(3) Agricultural Activities: –
In view of the increasing population in the modern era, high technology is being used in agricultural work.
To protect the crops from insects and to prevent weeds from growing,
various pesticides and herbicides are being sprayed on the agricultural land in a modern way,
due to which organic phosphates, chlorinated hydrocarbons, lead and mercury particles etc.
spread toxicity in the environment.
(4) Solvent Usage: –
Various types of solvents like dyes, varnishes, turpentine oil etc.
are used for the maintenance of vehicles, furniture, windows, doors, appliances, walls.
These solvents contain various volatile hydrocarbons and other volatile organic substances whose vapors reach the atmosphere and pollute it.
Similarly, volatile solvents (petrol, benzene, alcohol, spirit etc.) are used in bleaching and dry washing of silk, woolen clothes etc.
Their vapors also pollute the atmosphere.
(5) Mining and purification of ores: –
The atmosphere gets polluted due to various stages of mining and concentration of ores of different metals.
During the excavation of metal ores, along with the dust of metal particles, particles of various harmful radioactive substances also get dispersed in the atmosphere in sufficient quantities,
which reach the bodies of living beings and show their harmful effects for years.
(6) Atomic Projects: –
Today, in various nuclear projects around the world, electrical energy is produced from heat in which radioactive substances (U215. U238) are disintegrated.
In this process, particles of radioactive waste materials are emitted which remain in the atmosphere for several hundred years.
(7) Social Activities:-
Various customs and rituals of our society like burning of dead bodies after death,
fireworks used during various festivals and marriages produce various types of toxic gases and harmful radiation
(CO2, CO, organic particles, Ash, sulphur, potash, lead)
are emitted into the atmosphere due to which the atmosphere gets polluted.
(8) Individual habits: –
Smoking cigarettes, beedi, smack, heroin etc.
emit harmful substances like carbon monoxide into the atmosphere,
which not only affects the person but also the people around him.
Effects of Air Pollution
The effects of air pollution can be classified into the following two categories
(a) Immediate effects
(b) Long term effects
(a) Immediate effects:-
This means such effects which show their symptoms as soon as they are used for any reason:
such as irritation in the throat and eyes on breathing in the environment containing smoke emanating from vehicles and factories. Etcetera.
(B) Long-term effects:-
This includes such effects which are not visible immediately.
But they show their symptoms after some time.
For example- change in the composition of gases in the lower layer of the atmosphere,
accumulation of various pollutant elements and particles in the lower layer of the atmosphere and change in air weight.
The effects of air pollution can be explained under the following points: –
(1) Effects on human health:-
Air pollution has a very bad effect on human health.
This causes many respiratory diseases such as lung cancer, asthma and other lung related diseases.
Particles of many metals distributed in the air cause many diseases.
Lead particles especially cause diseases in the nervous system.
Nitrogen oxide causes many disorders in lungs, heart and eyes.
Ozone also causes eye diseases, cough and chest pain.
Due to the presence of carbon monoxide in the atmosphere, hemoglobin molecules in human blood start connecting with carbon dioxide molecules 200 times faster than oxygen,
due to which a feeling of suffocation occurs in respiration.
Staying in this condition for a long time can lead to death due to suffocation.
Various toxic chemical and radioactive substances released into the atmosphere from chemical gas plants and nuclear projects leave their long-term effects on human health.
For example, in the Bhopal gas tragedy that took place in India in 1984, many people were killed due to the leakage of methyl isocyanate,
while due to the effect of this gas, the babies of many pregnant women were born dead.
Even today, many babies are born crippled and mentally disturbed due to the effects of radiation from the atomic bombs dropped on Hiroshima and Nagasaki during the Second World War.
(2) Effects on other animal species: –
Like humans, air pollution causes respiratory disorders in other animals also.
Wild animal species are most affected due to excessive pesticides and other toxic chemicals present in the air.
As a result of precipitation of chloride compounds present in the atmosphere on the fodder (grass, wild plants) of animals,
they enter the body of animals and cause disorders in the bones.
Similarly, the presence of sulfur dioxide greatly affects the activity of bacteria present in the soil,
which has a direct impact on vegetation.
(3) Effects on vegetation:-
Air pollution also has adverse effects on vegetation.
The presence of air pollutants like chlorofluorocarbons, sulfur dioxide, nitrogen oxides etc.
leads to depletion of ozone and increase in the greenhouse effect of the atmosphere due to which vegetation gets destroyed due to increase in the temperature of the atmosphere.
Due to excessive particulate matter and photochemical fog in the atmosphere, there is a reduction in sunlight reaching the earth.
Due to which the food production process (photosynthesis) of plants gets hampered.
Which has direct and adverse effect on their growth.
Dust, smoke and other particles settle on the surface of the leaves of plants,
due to which the leaf stomata get blocked and the process of transpiration gets disrupted.
(4) Effects on materials:-
Air pollutants which cause air pollution not only affect animals and plants but also have adverse effects on various substances.
In the atmosphere, sulfur dioxide, sulfur trioxide and water react chemically to form sulfuric acid (H₂SO₂) which falls on the earth in the form of acid rain.
Metallic surfaces (iron, copper, aluminium, zinc) corrode when exposed to acid rain and form their own sulphate compounds.
Various buildings and structures made of limestone and marble lose their shine as well as strength due to exposure to acid rain.
For example, the world famous Taj Mahal of Agra is losing its shine due to acidic years.
Similarly, lead present in paints reacts with hydrogen sulphide (H₂S) to form lead sulphide (Pbs),
due to which the brown color of the painted surface turns black.
(5) Effects on Weather and Climate: –
Due to continuous process of air pollution, interference of air pollutants in the weather of that particular area is not a surprising phenomenon.
Such an incident becomes certain to occur only when the concentration of pollutants in the atmosphere increases unexpectedly.
Untimely rainfall in industrial cities, increase in temperature, decrease in the amount of light and presence of haze and fog etc.
are the results of air pollution.
MEASURES TO CONTROL AIR POLLUTION
Air pollution has taken a monstrous form today and if it is not controlled soon,
it will bring the entire biosphere back to its original form.
Therefore, various measures need to be taken to control air pollution.
(a) Measures to Control Domestic Pollution:-
1. Use of smokeless fuels in homes should be promoted. wood, coal, cow dung etc.
Use of electric heaters, cooking gas, solar energy powered appliances etc.
in place of traditional fuels controls air pollution.
2. Household waste (fruits, vegetable peels etc.) should be thrown in open places and deep pits should be dug and buried there.
Due to this, bio-fertilizer can be produced from their decomposition by microorganisms and the foul smell arising during their decomposition can also be avoided.
3. Burning of raw coal and raw wood should be banned because it emits more carbon dioxide, carbon monoxide and carbon particles.
4.There should be proper arrangement of windows, doors and skylights in the house and chimney should be arranged in the kitchens.
B) Measures to Control Vehicular Pollution:-
1.Vehicle manufacturing companies should manufacture such internal combustion engines
which allow complete combustion of the fuel used in vehicles and less amount of pollutants are emitted.
2. Air pollution can be reduced by adding additives to lead-free petrol and diesel and using them in vehicles.
3. Electric powered railway engines should be used in place of diesel railway engines.
4. There should be a ban on highly air polluting vehicles and provision for legal action
if the level of smoke generated by other vehicles exceeds the standard.
5. Battery operated vehicles should be used more and more.
(c) Measures to control industrial pollution
1. Proper arrangement of sufficiently high chimneys should be made in the manufacturing units of the industries where combustion process is used.
2.Bag filters should be attached to chimneys for disposal of particulate pollutants emitted from industrial establishments.
The ill effects of smoke can be avoided by using fabric filters or high energy scrubber devices.
3. There should be complete arrangements to prevent and control accidents in manufacturing units.
4. Only high quality and less polluting raw materials should be used in industries.
(d) Other Measures :-
1. Radioactive materials released from nuclear projects should be immediately converted into disintegrative materials.
2. Atomic bombs and other harmful nuclear tests should be limited.
3. There should be balanced use of pesticides and chemical fertilizers.
(Air pollution causes)