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 industrial production, and it combines with rain to become acid rain. Since acid rain contains a lot of sulphuric acid, it damages forests and buildings. Secondly, unburned hydrocarbons are also released in industrial production, and they become soot and fog in the air. Serious respiratory diseases will be increased because of the smog.
Next, the second cause of air pollution is transport. Two types of gases are released. Firstly, lead is released from petrol, and then people breathe leaded air, so lead enters their bloodstream.
Growing children are possible damaged because lead is a poisonous element. Secondly, carbon monoxide is released from vehicles' exhaust pipes and causes fog. The fog is harmful to people's respiratory organs, so serious respiratory diseases can be increased.
Another main cause of air pollution is the testing of nuclear weapons. Because radio-active particles are released and absorbed by vegetation in testing of nuclear weapons, and that people touch them by various approaches, they will be rapidly passed on to human beings. Radio-active matter can destroy human cells to result in diseases, such as cancer.
Finally, excessive crop spraying with pesticides is also a cause of air pollution. Pesticides 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...