Air pollution is a form of environmental degradation whereby the quality of air is significantly reduced due to introduction of any of various contaminants. This article discusses air pollution definition, types and examples; as outlined below;
Air Pollution Definition: 5 Ways to Define Air Pollution
Air pollution is the process by which air becomes impure or unhealthy as a result of natural disasters and human activities like dust storms, volcanic eruption, heat waves and electricity generation; that lead to the release of foreign materials into the air .
The above highlights some causes of air pollution, in an attempt to define it. Below is an alternative air pollution definition, that mentions some effects of air pollution;
Air pollution is an unsustainable condition involving the presence of harmful concentrations of foreign materials in air, that could lead to human health problems, economic losses, climate change, biodiversity loss, and other negative changes in the ecosystem .
Some potential solutions to air pollution are highlighted in the air pollution definition below;
Air pollution is the environmental impact of natural processes and human activities that involve release of contaminants into air; and whose solutions include energy transition, recycling, energy conservation, and policy enforcement.
The following air pollution definition attempts to outline the identifiable types of air pollution;
Air pollution is a phenomenon involving degradation of air due to the release of foreign materials in significant quantity, and which is of various types that include; indoor, outdoor, physical, chemical, and biological air pollution.
Lastly, the air pollution definition is outlined to include some examples of air pollutants;
Air pollution is simply the release of materials like particulate matter, sulfur dioxide, ozone, carbon monoxide and nitrogen dioxide, into the air or atmosphere in such quantities that cause degradation and may pose risks to the economy, environment and society .
Types of Air Pollution
Types of air pollution are; indoor, outdoor, physical, chemical and biological air pollution. They can be categorized based on location, causes, and nature of pollutants.
It is important however to note that the two main types of air pollution are indoor and outdoor pollution.
Types of air pollution are discussed individually below;
1). Indoor Air Pollution (as one of the Types of Air Pollution)
Indoor air pollution describes the presence of significant amounts of air pollutants within an enclosed space such as the interior of buildings.
This type of pollution is usually very hazardous to the health of individuals who occupy such enclosures, due to the high degree of proximity to pollutants. As a result, air pollution is generally worse indoors than outdoors.
Indoor air pollution is linked to many cardiovascular and respiratory ailments including lung cancer and asthma .
Examples of substances that can cause indoor air pollution are asbestos, carbon monoxide, radon, particulate matter, and volatile organic compounds (VOCs) like trichloroethylene and xylene.
2). Outdoor Air Pollution
Outdoor air pollution is the more common type than indoor pollution..
It involves the presence of air pollutants in open space or outdoor environment, so that these pollutants may accumulate in the atmosphere.
Like indoor pollution, outdoor air pollution can also be very hazardous, and accounts for a significant fraction of premature deaths in humans .
Other health problems linked to outdoor air pollution are; asthma, lung cancer, and dermal allergies.
Generally, the effects of outdoor air pollution include fog formation and low visibility, health challenges, acid rain, and climate change.
3). Physical Air Pollution (as one of the Types of Air Pollution)
Physical air pollution is air pollution that results mainly from physical processes. Examples of such processes include natural disasters like dust storms, and human activities like building demolition.
Generally, the pollutants involved in physical air pollution do not undergo any significant chemical alteration during or after their release into the air. Particulate matter is a common pollutant in physical air pollution.
4). Chemical Air Pollution
Chemical air pollution is a type of air pollution that is caused by, and involves, chemical transformations.
These chemical transformations are mostly reactions like combustion, or other processes whereby chemical compounds are created or altered.
An example of a common cause of chemical air pollution is electricity generation.
Pollutants linked to chemical air pollution include sulfuric oxides, nitrogen dioxide, ground-level ozone, and carbon monoxide.
5). Biological Air Pollution (as one of the Types of Air Pollution)
Biological air pollution is less common than the physical and chemical categories.
This type of air pollution can be directly linked to biological processes and/or organisms.
Examples of pollutants involved in biological air pollution include pollen, and bioaerosols which could contain pathogenic viruses and bacteria.
Examples of Air Pollution
Examples of air pollution are;
1). Indoor air pollution by carbon monoxide from portable electric generator
2). Outdoor air pollution by toxins from vehicular emissions
3). Physical pollution by particulate matter carried in dust storms
4). Biological pollution by bioaerosol in anaerobic digestion plant
5). Chemical air pollution by volatile organic compounds from contaminated marine ecosystems
Air pollution is significant decline in air quality due to the presence of any of various contaminants in the air.
Types of air pollution are;
1. Indoor Air Pollution
2. Outdoor Air Pollution
3. Physical Air Pollution
4. Chemical Air Pollution
5. Biological Air Pollution
Examples of air pollution are; carbon monoxide from electric generator, toxins from vehicular engines, particulate matter from dust storms, bioaerosol from waste-to-energy plant, and volatile organic compounds from water bodies.
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