1. Copyright © 2006-2011 Marshall Cavendish International (Singapore) Pte. Ltd. Depletion of the Ozone Layer Problem with ozone: At low altitudes, it can cause pollution problems, and breathing difficulties. It also causes photochemical smog. However, in the stratosphere, the ozone layer shields us from ultraviolet radiation from the sun. This radiation can cause skin cancer, genetic mutations and cataracts. In recent years, this ozone layer is depleting.

2. Copyright © 2006-2011 Marshall Cavendish International (Singapore) Pte. Ltd. CFCs were widely used as propellants for aerosols and as coolants in refrigerators and air conditioners. What is causing the depletion of ozone in the stratosphere? The depletion of the ozone layer is caused by chlorofluorocarbons (CFCs). CFCs are compounds containing the elements carbon, fluorine and chlorine.

3. Copyright © 2006-2011 Marshall Cavendish International (Singapore) Pte. Ltd.

4. Many countries have now agreed to ban the use of CFCs. Even if the use of CFCs is totally stopped at once, the depletion of the ozone layer will continue for many years due to the CFCs already present in the atmosphere.