The chemical composition of the atmosphere today is so different as compared to the atmosphere that existed before the Industrial Revolution, 1760 – 1830. To define air pollution, we should first consider all those sources that release harmful chemicals into the atmosphere and alter its chemical composition. First of all, all anthropogenic (man-made) emissions are air pollutants. Next, is the natural emission which can be divided into boogieing and genetic. Boogieing emissions result from the living world such as volatile organic compound emissions from forests and CHI emissions from swamp.
On the other hand, genetic emissions are from the non-living world, such as volcanic emissions, sea-salt emissions, and natural fires. So, keeping all these sources in mind, ‘air pollutant’ can be defined as any substance that is released into the air from anthropogenic, boogieing and genetic sources, which is maybe not a component of the natural atmosphere or which is present in higher concentrations than it is present naturally in the atmosphere, and may impose harmful effects either in short or long terms.
Therefore, air pollution can be defined as the presence of harmful substances n the atmosphere which is maybe not a component of the natural atmosphere or which is present in higher concentrations than it is naturally present in the atmosphere, that can impose short or long term effects, which is emitted by either anthropogenic, boogieing or genetic sources. AIR POLLUTANTS Air pollutants can be divided into primary’ and secondary pollutants.
Both primary and secondary pollutants are known to cause harm if present in high concentrations.
Primary pollutants are those that emitted directly into the atmosphere, such as the Carbon compounds(CO,CA,CHI,and Vic’s), Nitrogen compounds(NO,NON,and NH), Sulfur compounds(HAS and SIS), Halogen compounds(chlorides, fluorides, and bromides), and Particulate Matter or ‘aerosols’. (refer to the table below for Particulate Matter categories).
PARTICLE SIZE DESCRIPTION < 100 microns ‘inhalable’ since can easily enter the nose and mouth 10 microns thoracic’ since can penetrate deep in the respiratory system, PMIO < 4 microns ‘ href=”/cdn-cgi/l/email-protection” class=”__cf_email__” data-cfemail=”493b2c3a39203b282b09″>[email protected] because small enough to pass completely through the respiratory system and enter into bloodstream < 2. 5 microns PM2. 5, labeled ‘fine’ in the US < 0. 1 microns PMO. I, labeled ‘ultrafine’ table constructed by using information from : http://mvw. aiha. org/abs05/ pol 05. htm and http://wvvw. greenfacts. org/glossary/pqrs/PM1 0-PM2. 5- PMo. 1. htm ) Whereas, secondary pollutants are formed in the atmosphere from the primary pollutants (precursors).
The examples of those are NON and HON. (from NO), Ozone,03 (from photochemical reactions of nitrogen oxides and Voss), sulfuric acid droplets (from SIS) and nitric acid droplets (from NON), sulfates aerosols (from sulfuric acid droplets + NH ) , nitrates aerosols (from nitric acid droplets + NH) and organic aerosols formed from Voss in gas-to- article reaction. Acid rain is a result of the wet and dry deposition of these pollutants. In the following page, the health effects imposed by these pollutants are discussed. However, this primary and secondary pollutants are now divided into a smaller scope, namely outdoor and indoor pollutants.