 |
Published by
Australian Academy
of Science
|
|
Sun and skin – a dangerous combination
Box 5 | Australian research
|
Australian medical researchers have been in the forefront of investigations into the link between ultraviolet (UV) radiation and skin cancer. For example:
- CSIRO scientist Dr Mark Berman and his colleagues have developed a form of microscopy to diagnose melanomas without needing a biopsy of the material. The Image Analysis Group at CSIRO Mathematical and Information Sciences has developed an instrument for computer diagnosis based upon analysing pictures of the skin.
In collaboration with specialists from the Sydney Melanoma Unit and a medical instrumentation company, the scientists have put the knowledge of melanoma experts into a computer program. A special magnifying camera converts information from the skin into digital form, which the computer then analyses for possible melanoma, using its database compiled from the existing knowledge of experts. General practitioners without specialist knowledge will be able to use the system and come up with a faster and cheaper diagnosis.
Related sites
- Dr Bill McCarthy, of the Royal Prince Alfred Hospital in Sydney, is investigating children’s moles. He has found that children in Townsville have six times more moles than children in Melbourne. Using meters to determine levels of ultraviolet radiation in the cities and individual monitors on children, he is precisely correlating doses of ultraviolet radiation with skin changes. The number of moles are known to be a good indicator of the risk of developing melanoma later in life.
The work with children is especially important because it is when we are young that most of the sun damage is done. It pays to be careful at any time, but the ultraviolet radiation received in the first 20 years of life can be enough to ensure that a cancer develops 30 or 40 years later.
- The Bureau of Meteorology now presents daily forecasts of the intensity of UV-B radiation. This is useful in helping people make decisions about appropriate activities and clothing. The regular announcement on weather bulletins also helps remind people of the ever-present nature of ultraviolet radiation.
But forecasting ultraviolet radiation is not easy. The calculation must take into account the time, date, latitude, altitude, atmospheric ozone concentration and the possibility of cloud or haze, because all these factors can affect the amount of ultraviolet radiation reaching the ground. The Bureau has worked with the Cooperative Research Centre for Southern Hemisphere Meteorology to develop a special global computer model to help predict ozone concentration (ozone absorbs ultraviolet radiation) and calculate the amount of ultraviolet radiation that will pass through the atmosphere to the ground. Forecasters can then correct for the amount of cloud expected at any location around midday.
The effectiveness of clouds in screening ultraviolet radiation is complex. It depends partly on the thickness, composition and type of cloud. Most clouds block some ultraviolet radiation, but some types can actually increase the ground level intensity by reflecting the sun’s rays. When the sun is high in the sky, ultraviolet radiation can still penetrate thick cloud.
Related site
Other boxes
Box 1. The ultraviolet family
Box 2. Types of skin cancer
Box 3. The molecular mechanisms of skin cancer
Box 4. Diagnosing skin cancer
Box 6. Sunblocks and sunscreens
|
|
