CONTENTS

Introduction
Human Skin Cancer
Sunscreen and Fabric
The Mouse Model of Cancer
Studies Using Skin Tissue
Drugs and Sunlight
Plant and Algae Growth
Conclusion
Glossary
Bibliography

A Problem with the Ozone Layer

The ozone layer absorbs most of the ultraviolet radiaton coming from the sun and is very important for the survival of life on earth.

Ozone is a gas composed of molecules of three oxygen atoms (O3). There is a layer of ozone in the stratosphere which is most dense between 20 and 25 km above the earth's surface.

In 1984 scientists discovered there was a hole in the ozone layer above Antarctica. The hole appears each spring and is repaired when air containing normal levels of ozone is blown in. As it is being repaired at the end of spring the ozone hole drifts over Australia, allowing increased levels of ultraviolet radiation through.

It is estimated by scientists that a one per cent decrease in ozone levels produces between one and two per cent increase in ultraviolet radiation. The Melbourne Bureau of Meteorology has found that there has been an 8% increase in ultraviolet radiation during the summer since 1980.