The problem of air pollution

Read the text and do the tasks that follow.

Reading

Garbage, refuse, trash d natural pollutants

Naturally occurring gases

Dust, pollen, soil particles, c industrial pollutants

Pre-reading

Match the words in column A with the generalizing words in column B.

A B

1. ammonia, hydrocarbons, a respiratory diseases

organic acids, sulphur oxides

2. asthma, bronchitis, ‘killer smog’ b waste

What do you know about air pollution? Why is it dangerous to the environment?

Air pollution occurs when wastes dirty the air. People produce most of the wastes that cause air pollution. Such wastes can be in the form of gases or particulates. These substances result chiefly from burning fuel to power motor vehicles and to heat buildings. Industrial processes and the burning of garbage also contribute to air pollution. Natural pollutants include dust, pollen, soil particles, and naturally occurring gases.

The rapid growth of population and industry, and the increased use of automobiles and airplanes, have made air pollution a serious problem. The air we breathe has become so filled with pollutants that it can cause health problems. Polluted air also harms plants, animals, building materials, and fabrics. Air pollution also causes damage to the environment that cannot be reversed.

Industrial processes produce a wide range of pollutants. Oil refineries discharge ammonia, hydrocarbons, organic acids, and sulphur oxides. Metal smelting plants give off large amounts of sulfur oxides and particulates containing lead and other metals. Plants that make aluminum expel fluoride dust. Burning of solid wastes often creates a very visible form of air pollution--thick, black smoke. The burning of garbage, leaves, and other refuse is banned in most countries. Forest fires and structural fires also contribute to air pollution. In rural areas and in developing countries, the burning of forests and grasslands to clear areas for farming is a major source of air pollution.

When people breathe polluted air, the impurities can irritate their air passages and their lungs. Particulates often remain in the lungs and can worsen such respiratory ailments as asthma and bronchitis. Ozone reduces resistance to colds and pneumonia.

In London in 1952, about 4,000 people died of respiratory diseases during a "killer smog." Today, such extreme events are rare because of government emission standards, which limit pollutants released by factories and other sources. However, air pollution still contributes to a large number of deaths each year.

Air pollutants can stunt the growth of crops, harm livestock, and destroy crops as well. Forests also have been damaged by air pollution.

Some pollutants are not poisonous but can cause damage by altering the earth's atmosphere.

Air pollution is closely related to other forms of pollution. Acid rain pollutes lakes and streams and, in high concentrations, can harm soil fertility.

Дата добавления: 2014-11-16