When we use the atmosphere to dispose of waste products we cause air pollution. In the middle of the twentieth century this was mostly due to emissions from the chimneys of factories and houses. These caused the infamous “pea-soup” smogs that led to thousands dying as a consequence.
The Clean Air Acts of the 1950’s and 1960’s and subsequent environmental protection laws, led to taller factory and power station chimneys to disperse pollution more widely, and improved technology led to more efficient combustion and fewer pollutants being emitted. The Acts also introduced smokeless zones in major cities, bringing an end to inefficient, smoky, open fires. From the late 1960s natural gas gradually replaced gas from coal, further reducing the use of solid fuel in homes.
Today, it is motor vehicles that are the source of most air pollution problems in our towns. The huge growth in motor vehicle numbers during the last 50 years has seen our towns and cities become congested with cars and vans. The exhaust fumes emitted include tiny particles that enter our lungs, and from there enter the bloodstream, causing harm to health, especially in the very young and those with respiratory problems.
There are also other potential sources of air pollution of local importance, such as the increasingly popular wood burning stoves. These should be used to burn well-seasoned wood, but are sometimes used to dispose of waste wood or ‘green’ wood, which can then emit high levels of pollution. It’s also a really bad idea to keep stoves in overnight with a trickle of air, as emissions of toxic smoke around the house will be high, and your chimney will suffer.
These infographics illustrate where pollution comes from and the effects it has. It is worth noting that for small particulates and oxides of nitrogen, the pollution can be very localised to busy roads and junctions, with much lower levels on nearby streets with low traffic.
You can learn more about air pollution through these links:
http://www.cas.manchester.ac.uk/resactivities/pollution/background/
Somerset Air Quality 