Air quality is an important factor in a person's quality of life. When air quality is high, the outdoors are fresh and enjoyable. This corresponds to a greater well-being of individuals, including enhanced health and happiness.
Poor air quality however can be attributed to many negative effects, including poor visibility, difficulty breathing, disease and even death. Many Asian countries are suffering the most from poor air quality, and experience daily smogs, leading to a high number of deaths due to lung and heart disease. Many developing countries around the globe are also experiencing the same consequences.
Many countries have an air quality index (AQI), which shows how toxic the air may be to the population and specific groups of people. Follow the links below for the specific locations:
Air quality is worsened when various pollutants are introduced into the air, especially in high quantities over a small area. These pollutants can be emitted by many sources, but the most dominant contributor within cities are vehicles burning gasoline and other oil products. The burning of coal also produces many harmful pollutants, however in most places around the world coal is burned relatively far away from cities, so the air pollution from coal plants has a less visible effect on air quality.
The pollutants that deteriorate air quality include nitrogen oxides, sulfur oxides, particulate matter, volatile organic compounds, and more. These are considered primary pollutants, since they are emitted directly into the atmosphere. A majority of them also react in the air to form what are called secondary pollutants, and these include ozone and peroxyacyl nitrates (PANs). A combination of many of these leads to the formation of smog and photochemical smog, which may stay over a given location for an unsafe amount of time.
Visit the pages below for more information on pollutants and how they affect health and the environment.