What is in air pollution?

 

Clean air is essential for our bodies to live as it supplies the oxygen for cellular respiration. We breathe air into and out of our lungs all the time from our birth to our death. Unfortunately, some of our other activities release substances that pollute the air and are harmful to humans, plants and animals. Pollution is the contamination of the natural environment by harmful substances as a result of human activities. Pollution can happen on a very small, local scale – every time you drop litter, or a dog fouls the street, the local environment is polluted. On the other hand, pollution happens on a very large scale too, affecting whole countries – acid rain, global warming and the ozone hole are all examples of the effects of large-scale air pollution you will be learning about here. A pollutant can be defined as something that contaminates the air, soil and water. In this section we will be concentrating on substances which pollute the air

Air pollution comes in various forms, each of which has serious implications for our health and well-being as well as for the whole environment. One type of air pollution is smoke produced by burning fuel for energy. Much of the fuel we use is fossil fuel – coal, oil or gas, or electricity produced by burning them. Fossil fuels contain chemicals known as hydrocarbons. When these fuels are burnt, tiny particles of unburnt hydrocarbons are released into the air. Diesel smoke is a good example of this. The particles are very small pieces of matter. This type of pollution is sometimes referred to as ‘black carbon’ pollution. The exhaust from burning fuels in cars, homes and industries is a major source of pollution in the air. Even the burning of wood on our fires can release significant quantities of soot into the air causing local air pollution. Smoke pollution worldwide is thought to be causing global dimming, blocking out some of the light from the sun. Another major cause of air pollution is the production of carbon dioxide. Carbon dioxide is produced by living organisms as a waste product of respiration. It is used by plants in the process of photosynthesis. Carbon dioxide is also produced as a result of burning wood and fossil fuels.