Air Pollutants: Summary of Their Sources and Effects
By Irina Bright.
This article is part of our Environment section
See the complete list of all our Pollution Articles here.
Below is an overview of air pollutants based on our Air Pollutants article here.
Though effects of pollutants present in the air on humans are well known, they are less known in respect of other higher forms of animals. But we assumed that in some cases these effects may be similar between humans and other animals, and that is why we have provisionally put these two groups together.
Name |
Form & Properties |
Sources |
Health & Other Effects |
Other Notes |
Colorless gas with a sharp, suffocating odor. |
Anthropogenic:
Natural:
|
Human & Animal Health:
Environment: As part of acid rain:
|
Formed as a result of fossil fuel combustion. |
|
Nitric oxide (NO) and Nitrogen dioxide (NO2). |
NO is a colorless gas. NO2 is a gas of reddish-brown color with a distinct sharp, biting odor. |
Anthropogenic:
Natural:
|
For NO2: Human & Animal Health:
Environment: As part of acid rain:
Also:
|
Formed as a result of fossil fuel combustion. |
Colorless, pungent, hazardous caustic gas. |
Agriculture is the biggest source of ammonia emissions, with the following breakdown:
|
Human & Animal Health:
|
||
Colorless, odorless, highly toxic gas. |
Anthropogenic:
|
Human & Animal Health:
|
This air pollutant is formed as a result of incomplete fossil fuel combustion. |
|
Organic compounds which easily evaporate. They include:
|
Anthropogenic:
Natural:
|
Human & Animal Health:
Also as part of ozone:
Environment: As part of ozone:
|
These air pollutants take part in the formation of ozone and, therefore, photochemical smog. |
|
Colorless, poisonous gas with a sharp, cold, irritating odor. |
Ozone is not emitted directly into the atmosphere by sources. It is a secondary pollutant, i.e. it is formed during the reaction between nitrogen dioxide and hydrocarbons (primary pollutants) in the presence of sunlight. |
Human & Animal Health:
Environment:
Also:
|
Considered an air pollutant in the lower layer of the atmosphere (troposphere), but beneficial in blocking ultraviolet sun rays in the upper atmosphere. |
|
Compounds which are resistant to degradation and persistent in the environment. |
Anthropogenic:
|
Human & Animal Health:
|
Exposure to persistent organic pollutants takes place through diet (specifically, consumption of animal fats), environmental exposure or accidents. |
|
Tiny fragments of solid or liquid nature suspended in the air. |
Anthropogenic:
Natural:
|
Human & Animal Health:
|
Most dangerous particulates are the ones less than 10 µm (micrometres) in diameter as they can be easily inhaled and trapped in the system. |
Written by: Irina Bright
Original publication date: 2008
Republication date: 2020