We continue to live under the misguided belief that a
tanned body is a healthy body. As a result, incidents of malignant and
non-malignant skin cancers are growing world-wide at epidemic proportions.
The rate is expected to increase dramatically in the future as ozone depletion
permits more UV-B rays to reach the ground. There is compelling evidence that
solar ultraviolet radiation is a complete carcinogen, acting on all major
stages of cancer: its initiation, its promotion and its progression. Children
are particularly at risk. A severe sun burn in childhood dramatically
increases an individual's chances of developing some form of skin cancer later
in life.
Even at current UV-B exposures, certain forms of skin cancer affect 1 in 5
people in the United States and as many as 2 in 3 people in Australia. Such
cancers are becoming increasingly common in younger people.
Between 1979 and 1993, the incidence of non-melanoma, the most common form of
skin cancer, is estimated to have risen an average of 10 per cent in the
Northern Hemisphere, between the latitudes 55 degrees N and 35 degrees N.
Even bigger increases are believed to have occurred in the Southern
Hemisphere. UNEP forecasts that a sustained 1 per cent decrease in
stratospheric ozone will result in a 2 per cent increase of this type of
skin cancer. On the basis of an estimated 10 per cent reduction in ozone, a 25
per cent increase in non-melanoma skin cancer rates has been predicted
for temperate latitudes by 2050.
Less common, but much more dangerous, are malignant melanomas which effect the
pigment cells in the skin and which can spread rapidly to the blood and
lymphatic system. These have become increasingly frequent throughout the
world over the last 40 years and, although detection and recovery rates have
improved, they already represent the most common cause of
cancer-related deaths in Australian adults under 45 years of age. Between the
periods 1978-82 and 1983-87, for example, melanoma incidence increased in
most European and Scandinavian countries, with increases from around 9
per cent in the Netherlands too as much as 56 per cent in Scotland.
Mortality rates have also increased rapidly, by up to 4 times in both Canada
and in the Netherlands between 1950 and 1990. In 1991 the US Environmental
Protection Agency projected that over the next fifty years 12 million
Americans will contract skin cancer and 200,000 will die from malignant
melanoma. In 1994, UNEP once again confirmed that increases in UV-B
radiation are likely to increase "the incidence and morbidity from skin
cancer" and that "epidemiological data indicate that the risk of melanoma
increases with sunlight exposure, especially during childhood."
