With the rapid development of society, pollution is becoming more and more serious all over the world. Air pollution is the most harmful enemy to human's health and can take many forms. I will describe four main reasons of air pollution and their effects in this essay. First of all, the first cause of air pollution is burning of fossil fuels in industry. Two types of gases are released. Firstly, sulphur dioxide is released in …showed first 75 words of 343 total…

…showed last 75 words of 343 total…are poisonous chemicals, and although they can be carried to anywhere by wind to kill pests, they harm to plants and animals at the same time. These poisonous chemicals concentrate in food by plants; therefore they usually have bad effects on health of human beings. To sum up, there are various causes of air pollution, with serious effects on human beings' health. Though it is difficult to avoid, it may be decreased by people's effort.