Air pollution is regarded as one of the most environmemtal issue facing us today.According to statistics,there are approximately 4,2 million death per year because of air pollution,and nearly 99% of the world population live in places where air is polluted.

There are a number of causes why air pollution takes place.

A primary source of the spreading of toxic pollutants into the air is burning fossil fuels.For example,when fossil fuels like coal or oil are burned,they emit greenhouse gases and chemical substances which lead to the formation of smog and acid rain decreasing the air quality we breather every day.Another major contributing factor is vehicle exhaust fumes.Automobile emission through engine pipes is a vivid example.Containing mononxide and a poisonous gas,they present a large amount of smokes that travel straight into the atmosphere.

Air pollutants produce many different types of effects on the human health and environment.It poses a wider scale problems for respiratory systems causing long-term diseases such as lung cancer and asthma.