Air pollution is a pressing concern among the different environmental issues that are prevalent in the world. It is the reason behind hundreds of thousands premature deaths in several countries.
The air that we breathe is contaminated with dust particles, exhaust from automobiles, chemical fumes from factories and industries, smoke and other particulate matter. These unwanted materials make their way into our airway when we respire and cause various respiratory problems like difficulty in breathing, lung inflammation, lung function decrease, asthma etc. Researchers have also linked air pollution to adverse impacts on our central nervous system.
Air pollution effects wildlife and plant life. The particulate matter can change soil chemistry and consequently bring changes in the growth of vegetation. Introduction of more gases like nitrogen oxides, sulfur oxides, carbon dioxide etc. also play a role in formation of harmful ozone and acid rain which effects all living organisms.
Generally, air pollution has been divided into two types.
1. Indoor pollution
It is the pollution of air caused by the introduction of materials from smoking and burning fossil fuels such as kerosene, petroleum and coal indoors. Fuels are burned indoors for cooking and cooling or heating purposes. Chemicals from cleaning products, wall paints, pesticides and air fresheners also contribute to indoor air pollution.
One half of the population in the world or 80% of the population in South Asia and Africa is affected by indoor air pollution from burning of coal and biomass. It is assumed that indoor air pollution is much worse than pollution outdoors.
2. Outdoor pollution
The levels of outdoor air pollution reach their peak in developing countries, most of them from Asia. The air outside is polluted mainly from vehicle exhaust and emissions from industries. Several pollutants are mixed in the air and a large portion of the world population is regularly exposed to harmful air quality.
Air pollution can also be divided into other types. According to the American Lung Association, the two major types of air pollution which harm human health are
Smog is the mixture of two components; smoke and fog. The term was introduced first in mid-20th century in London.
Its primary component is harmful ozone found at ground level. Smog is formed as a result of complex photochemical reactions that involve nitrogen oxides and volatile organic compounds. Smog causing pollutants are found in sources like exhaust from vehicles, fumes from power plants and solvents.
Smog can cause several health problems like breathing problems, decrease in resistance to colds and infections, irritation of eyes and throat, asthma etc.
Particle pollution is also a serious issue in the world. It is widespread in cities and urban areas. This kind of pollution is caused due to the exhaust from burning diesel fuels in heavy transportation, burning of fuels in power plants and burning wood. It has been known to increase problems of heart diseases, cancer of the lungs, coughs and asthma.
Other types of air pollution are
Greenhouse gases are responsible for the trapping of heat in the earth atmosphere which results in the warming of the planet. These gases are increased significantly because of human activities such as exhaust from vehicles and industries, agriculture and generation of electricity. Rise in greenhouse gas emissions help in the increase of global temperature.
Natural air pollution
It is the air pollution caused by natural causes. Sometimes nature is also responsible for polluting the air. Volcanic eruptions, radioactive decay and forest fires are natural causes.