Air pollution is a very real and potent threat that we face in our lives today, but many people are under the misconception that it is only caused by man-made sources. Admittedly, man-made sources are the primary source of pollution in our atmosphere in the form of smoke, smog and other harmful materials, but there are several natural factors that lead to it as well.
Air pollution can be defined as the presence of any harmful material in the air and the atmosphere that can cause damage to human beings and other living organisms. These materials can cause their damage either by entering the respiratory system of these organisms or by attacking their outer skin layers externally. Moreover, some forms also lead to damage of buildings, other man-made structures, rivers, and several other areas.
The Natural Causes of Air Pollution
A fire that occurs in a highly vegetation infested area through natural causes is known as a bush fire, and this is a very potent natural source of air pollution. There are several different causes that lead to forest fires, and the fact is that they are caused naturally without any human intervention. These fires spread very rapidly, and release pollutants like smoke and carbon monoxide into the atmosphere. Though carbon monoxide is present in living bodies in small amounts, it can be toxic in nature when sniffed in larger amounts. Forest fires also lead to unpredictable weather changes and cyclones, and all this leads to a severe loss of life in the long run.
A volcano is an open fissure on the surface of the earth from which lava and volcanic ash escapes on a regular basis. There are several active volcanoes that are found around the planet today, and along with the air pollution that they cause, they can also be a source of danger to life forms. Carbon dioxide and sulfur dioxide are the primary gases that are released during volcanic eruptions, and these lead to dire consequences to the earth's atmosphere and to all the life forms that reside here. Other gases like hydrogen sulfide, hydrogen chloride, hydrogen fluoride, carbon monoxide, halocarbons and some metal chlorides are also released into the atmosphere in smaller traces. The materials released also lead to acid rain in many parts, and the volcanic ash that follows disrupts air travel and many other activities. The recent eruptions of Eyjafjallajökull over Iceland in 2010 also led to several restrictions in air travel over Europe.
Though dust particles and dirt do not cause toxic effects in the human body, they are capable of inducing many respiratory diseases in human beings. These dust particles move around in the atmosphere due to strong winds, especially in geographical areas where wind erosion is a common occurrence. This factor is not a very major contributor towards air pollution, but it does play a small role and is one of the most underestimated forms of air pollution.
Farm animals like cattle release methane into the atmosphere during the end stages of their digestive cycles. Methane gas affects the ozone layer in the atmosphere since it is a very potent greenhouse gas, and it is also highly inflammable when it combines with other elements in the air. Moreover, it can lead to severe asphyxiation if someone is trapped in a closed room with the presence of methane gas in the air. This is a factor that building construction sites also take into account, since the presence of methane in the airways of the building can lead to dire consequences.
Nuclear elements like uranium are found inside the earths surface, and when these elements decompose they release a noble gas known as Radon into the atmosphere. This gas is highly radioactive in nature, and it can cause some serious health damage to people who breathe the air that contains it. Interestingly, after smoking, Radon intake is the second largest contributing factor to lung cancer in human beings, so all possible measures to prevent the spread of Radon must be taken.
Other factors like the dispersal of large amounts of pollen from flowers and the emission of VOCs (Volatile Organic Compounds) which get oxidized and transformed into aerosols from plants and trees also lead to air pollution which is not caused by man-made sources. As you can see, there are plenty of natural causes that are out of our control as well. Most of these sources can be countered in certain ways, but if you are under the impression that air pollution is caused solely by man, then you are mistaken.