Air Pollution FAQ

Air pollution is the contamination of the atmosphere by biological materials, chemicals or particulate matter that is harmful to humans or other living organisms. The substances that cause air pollution are called as pollutants.

What causes Air Pollution?

There are many different substances that causes air pollution and these pollutants come from variety of sources. The sources of air pollution can be natural or man-made. At present, humans are the main source for air pollution. Carbon dioxide is one of the main pollutants and it is used in various industries for manufacturing process.  Human activities like deforestation, combustion of fossil fuels, and gases released from automobiles have also increased the percentage of carbon dioxide in the atmosphere. Other harmful pollutants that contribute much to the air pollution are carbon monoxide, sulfur dioxide, and nitrogen dioxide.

Natural causes of air pollution are volcanic eruptions, forest fires, pollen dispersal, natural radioactivity, wind erosion, and evaporation of organic compounds.

What are the Effects of Air Pollution?

Air pollution is a global problem and effects of air pollution are numerous. Air pollution can negatively affect human beings and can cause breathing problems, cough, burning eyes, and sometimes even death. Smog reduces visibility and acid rain caused by chemicals can damage property. Air pollution can harm wildlife, forests, agriculture, and water resources. Air pollution causes short term (bronchitis, pneumonia, or headache) and long term (lung cancer, damage to kidney and brain, or heart disease) effects on human health. Continuous exposure to air pollution causes lungs problem in growing children.

Evolution of Air Pollution

Air pollution, especially in cities, is not a new problem. Natural events, such as dust storm and forest fire caused the first air pollution. The use of coal during the industrial revolution contributed much to air pollution. Coal became the primary fuel and during foggy conditions, pollution level increased leading to urban smog. The Great London Smog of 1952 led to more than 4000 deaths. In 1956, Great Britain passed Clean Air Act and in 1963, the United States congress passed the Clean Air Act. The last several decades, pollution has increased tremendously due to the use of automobiles. The exhaust from automobile contains large number of harmful substances, including carbon monoxide that increases the level of air pollution.

What is the ozone layer, what does it do?

The ozone molecule in the stratosphere (one of the region of Earth’s atmosphere) is called ozone layer and it blocks the sun’s harmful ultraviolet radiation. This layer is the Earth’s natural sun block. Ozone is a form of oxygen molecule. Each ozone molecule consists of three oxygen atoms and its chemical formula is O3.

The diminished ozone layer allows more ultraviolet radiation to reach the Earth’s surface and overexposure to UV rays can cause skin cancer, weakened immune system and cataracts.