This is Engineers Rail– The number one portal for all your engineering queries.
This article will provide you with a complete guide on Air Pollution Including the Definition, Sources, Effects, Control, And Prevention as written in the title of this article.
So, without much delay, Let’s get started…
Air pollution definition-
Air pollution may be defined as- “The presence of one or more contaminants like dust, smoke, mist, and odor in the atmosphere which are injurious to human beings, plants, and animals.”
Also, ”The contamination of air with dust smoke and harmful gases is called air pollution.”
Air pollution is generally accomplished through the pollutants of gases and solid and liquid particles of both organic and inorganic chemicals.
It is true that air is never pure because some gases such as SO2 CO2 hydrogen sulphide emissions from volcanoes, swamps, dust, salt spray from plants, etc are continuously added to the air by these natural processes.
Thus the air becomes polluted when its natural composition is disturbed.
The atmosphere is a gaseous envelope that surrounds the earth from all sides and the air is a composition of several gases mainly nitrogen, oxygen, argon, and carbon dioxide.
Air is very important for all types of life in the biosphere.
Causes of Air Pollution-
There are two major causes of air pollution as follows:
- Natural sources
- Man-made sources:
1. Natural sources-
Natural sources such as volcanic eruptions, deflation of sand and dust, forest or wildfires of natural vegetation, etc.
2. Man-made sources-
Man-made sources with human activities Such as industries, and factories. urban centers, aircraft, nuclear experiments, automobiles, agriculture, and power plants.
Sources of Air Pollution-
The principal air pollutants emitted from these different sources are as follows:
- Carbon compounds
- Sulphur compounds
- Nitrogen Oxides
- Fluoride carbon
1. Carbon Compounds-
These are mainly CO2 and CO the former released by the complete combustion of fossil fuels and the latter by automobile exhausts.
2. Sulphur Compounds-
These include SO2, H2S and H2SO4. Mostly released by fossil fuel-based power generating plants and industrial units as refineries.
3. Nitrogen Oxides-
These include chiefly nitrogen monoxide, nitrogen oxide, and nitric acid mostly released by automobiles, power plants and industries.
4. Fluoride Carbon-
These come from industries, insecticides spray, etc.
These are chiefly benzene, benzpyrene, etc which are mostly discharged by automobiles and industries.
These include mainly lead, nickel, arsenic, beryllium, tin, vanadium, titanium, cadmium etc. Present in the air as solid particles or liquid droplets or gases.
Its level may rise in the atmosphere due to human activities.
Effects of Air Pollution-
There are several effects on various things due to air pollution, some of those are listed and described below-
- Effects of air pollution on human health
- Effects of air pollution on economy
- Effect of air pollution on plants
- Effect of air pollution on animals
- Environmental Shades
1. Effects of air pollution on Human Health-
Air pollution causes several kinds of damage to man, animals, and plants and also to weather, climate and atmospheric process.
Our physical and psychological well-being is affected differently by the kind of air pollution we are exposed to.
There are many organs and bodily functions that can be harmed the consequences include:
- Respiratory diseases
- Cardiovascular damage
- Fatigue, headaches, and anxiety
- Irritation of the eyes, nose, and throat.
- Harm to the liver, and blood
- Nervous system damage.
The effects of air pollution are hard to ignore. Watery eyes, coughing, and difficulty in breathing are acute and common reactions.
Other conditions associated with a high level of air pollution include emphysema and chronic bronchitis as well as lung cancer.
Pollutants of air pollution can affect cardiovascular health by hardening the arteries and increasing the risk of heart attack and strokes.
There is even emerging evidence that air pollution may be linked to mental health conditions and degenerative brain diseases. So in the end, we can say the health effects of air pollution are serious.
One-third of deaths from stroke, lung cancer, and heart disease are due to air pollution. This is having an equivalent effect to that of smoking, and tobacco uses and is much higher than say the effects of eating too much salt.
Air pollution has become a critical issue in many developing countries lately. The issue has received a lot of media attention especially since it is responsible for premature deaths and other health issues.
2. Effects of air pollution on Economy-
The market impacts of outdoor air pollution which include impacts on labor productivity, health expenditures, and agricultural crop yields are projected to lead to global economic costs.
India lost more than 8.5% of its GDP in 2013 due to the cost of increased welfare and lost labour due to air pollution.
The delay of goods and passenger trains, flights, and freight during winter due to haze is a straightforward example of how air pollution is affecting our economy.
Employees are the backbone of any business. Air pollution is harmful to health and responsible for various diseases, Like lower respiratory infections, strokes, cancers, asthma, coughs, etc.
It is evident from studies that higher ambient air pollution has a significant association with the number of times an employee, takes time off work owing to illness which directly affects the productivity of the business.
Air pollution also affects the recruitment process of businesses, many talented employees do not want to work in cities with air pollution.
In order to improve air quality there are different solutions for businesses. Some interventions appear small but have potentially large benefits and co-benefits.
3. Effects of air pollution on Plants-
The effects of air pollution on plants are widely seen and damage all plants including our food crops and trees.
Air pollution comes from many sources such as the smoke stack in a factory, car exhaust, or off-gassing from paint or producing plastic.
The chemicals responsible for the pollution include carbon, sulphur, and nitrogen oxides. Plants usually show damage in a variety of ways including visible signs of damage like necrotic lesions, stunted plant growth, or changes in colour.
Ozone holes in the atmosphere also harm plants. Holes in the upper atmosphere allow excess ultraviolet light to pass through the atmosphere leading to plant damage.
The burning of hydrocarbons in motor vehicle engines gives rise to various harmful gases such as nitrogen monoxide etc. It is a major harmful element for plants.
Polluted air is harmful to man and the biosphere on the whole as well.
The deposition of particulate matter containing toxic metals affects the growth of plants. The particulate matter after deposition on plant leaves blocks the stomata opening of plants and reduces plant growth.
The particulate matter with acid rain reduces the pH of the soil which makes the infertile.
Air pollutants affecting plants are sulfur oxide, fluoride components, ozone, chlorine, ammonia, etc.
Forms of damage to the leaves due to air pollution-
It reduces crop yields and makes fruit smaller and lighter and less nutritious tissue, needles and fruit.
4. Effects of air pollution on Animals-
All animals despite their size can be affected by pollution. Animals depend on oxygen that comes from the air and when the air is contaminated harmful gases and particulates are inhaled.
5. Environmental Shades-
The environmental shades include-
- Acid rain
- Global warming
- Tropospheric Ozone
A. Acid Rain-
When water droplets in clouds combine with acidic air pollutants, the water turns acidic. Once the droplets hit the ground, acid rain causes damage to the environment.
Not only does acid rain harm animals and fish but it also kills trees. Once acid rain soaks into the ground, the soil becomes unfit for habitat and living creatures.
Air pollutants like Chlorofluorocarbons(CFC) have been known to destroy parts of the ozone layer. The stratosphere shields the plant from the ultraviolet radiation from the sun.
Ultraviolet radiation harms wildlife damages plants and causes skin cancer in humans.
C. Global Warming-
The planet is warming due to greenhouse gases which include carbon dioxide, methane, nitrous oxide, and water vapor. These gases are released into the atmosphere from air pollution.
- Related Article: Global Warming – Definition, Causes, Effects, Control And Prevention
D. Tropospheric Ozone-
Ozone molecules show up near the surface of the earth leading to air pollution. When ozone molecules are near the ground it causes damage to the lung tissues of animals.
Air Pollution Control Method-
There are many kinds of equipment that can be used to reduce particulate emissions. Physical separation of the particulates from the air using:
- Settling Chambers
- Cyclone Collectors
- Wet scrubbers
- Electrostatic precipitators
1. Settling Chambers-
Settling chambers use gravity separation to reduce particulate emissions.
The air stream is directed through a settling chamber which is relatively long and has a large cross-section causing the velocity of the air stream to be greatly decreased and allowing sufficient time for the settling of solid particles.
2. Cyclone Collectors-
A cyclone collector is a cylindrical device with a conical bottom that is used to create a tomado-like air stream.
A centrifugal force is thus imparted to the particles, causing them to cling to the wall and roll downward while the cleaner air steam exists through the top of the device.
An impinger is a device that uses the inertia of the air stream to impinge mists and dry particles on a solid surface.
Mists are collected on the impinger plate as liquid forms and then drips off. While dry particles tend to build up or re-enter the air stream.
4. Wet scrubbers-
Wet scrubbers control particulate emissions by wetting the particulate in order to enhance their removal from the air stream.
Wet scrubbers typically operate against the current by a water spray contacting the gas flow.
5. Electrostatic precipitators-
Electrostatic precipitators are devices which uses an electrostatic field to induce a charge on dust particles and collect them on grounded electrodes.
Electrostatic precipitators are usually operated dry but wet systems are also used. Mainly by providing a water mist to aid in the process of cleaning the particles off the collection plate.
One of the oldest and most efficient methods of particulate control however is filtration.
The most commonly used filtration device is known as a bag house and consists of fabric bags through which the air stream is directed.
Prevention of Air Pollution-
There are several types of air pollution that can be controlled by employing modern technology and scientific research but the costs are to be borne by the public in the form of higher prices for manufactured goods.
The main sources of air pollution are:
- Industrial development
- Power plants
The following are some of the measures to be followed for controlling air pollution by automobiles-
- To check pollutants emissions from the vehicular exhaust.
- To control evaporation from fuel tanks and carburetors.
- To use the filters
- To control through Law
2. Industrial Development-
Air pollution by industry and lower plant wastes can be checked by devising measures for the removal of particulate matter and gaseous pollutants from the wastes.
The three types of equipment or devices used are:
- Cyclone collectors
- Electrostatic precipitators
- Control through law
3. Power Plants-
The following four methods can be used to control air pollution from gaseous pollutants or coal-based power plants-
- Wet system
- Dry system
- Wet dry system
- Control through Law
This was all about Air pollution. I hope, I have covered all the sections regarding this topic. If I left something, Comment down below and I will try to add those.
If possible, Share with needy ones and bookmark to Engineers Rail for more convenient readings.
These are some suggested articles, you should never miss-
Abhishek Tiwary is a blogger by passion and a Quality Engineer by profession. He completed his B.Tech degree in the year 2017. Now working in a reputed firm. He loves to share his knowledge with others.