Air pollution

Air pollution is a large number of gases, droplets and particles that reduce the quality of the air. Air can be polluted in both the city and the country. In the city, air pollution may be caused by cars, buses and airplanes, as well as industry and construction. Air pollution in the country may be caused by dust from tractors plowing fields, trucks and cars driving on dirt or gravel roads, rock quarries and smoke from wood and crop fires.

Ground-level ozone is the major part of air pollution in most cities. Ground-level ozone is created when engine and fuel gases already released into the air interact in the presence of sunlight. Ozone levels increase in cities when the air is still and the sun is bright and the temperature is warm. Ground-level ozone should not be confused with the "good" ozone that is miles up in the atmosphere and that protects us from radiation.

Fortunately for most healthy people, the symptoms of air pollution exposure go away as soon as the air quality improves. However, certain groups of people are more sensitive to the effects of air pollution than others. Children probably feel the effects of pollution at lower levels than adults. They also experience more illness, such as bronchitis and earaches, in areas of high pollution than in areas with cleaner air.People with heart or lung disease also react more severely to polluted air. During times of heavy pollution, their condition may worsen to the point that they must limit their activities or even seek additional medical care. In the past, a number of deaths have been associated with severely polluted conditions.

Some of these gases can seriously and adversely affect the health of the population and should be given due attention by the concerned authority. The gases mentioned below are mainly outdoor air pollutants but some of them can and do occur indoor depending on the source and the circumstances.Tobacco smoke generates a wide range of harmful chemicals and is a major cause of ill health, as it is known to cause cancer, not only to the smoker but affecting passive smokers too. It is well-known that smoking affects the passive smoker (the person who is in the vicinity of a smoker and is not himself/herself a smoker) ranging from burning sensation in the eyes or nose, and throat irritation, to cancer, bronchitis, severe asthma, and a decrease in lung function.