For Surgeons

GenB

Sun Damage

The sun has traditionally been the friend of mankind from the time that man emerged from the rift valley. Sunrise has always heralded the dawn of a new day with the prospect of a new start and new life.

The sun and earth are inseparably linked in our solar system and our planet may be the only one to have a surface atmosphere capable of sustaining human life as we know it.

The earth’s atmosphere protects us from the sun’s rays in a way that makes life possible but still allows enough energy to pass through to warm the surface. It is this atmospheric layer that plays a crucial role in determining how the sun affects us. Global overpopulation has more recently begun to have a major effect on the atmosphere of the earth and thus the way in which the sun’s energy impacts on our bodies. South Africa has among the highest monitored ultra violet levels anywhere in the world. The South African winter sun is now more damaging than the Mediterranean summer sun.

While we need a certain amount of sun exposure, for example to maintain our vitamin D levels, too much exposure can be harmful.

Unfortunately the visible evidence of sun damage, in the form of photoaging, may take many years to appear while devastating damage to the cells of the skin occurs very early when we are not even aware of it.

Photoaging is the result of changes to the skin following sun exposure. The skin becomes dry, scaly, leathery and deeply wrinkled.

The more medically important result of sun exposure however is the damage that occurs to the cells in the skin. Ultraviolet radiation has the capacity to cause DNA damage to the cells and also to alter their immune response. These cells can then break free of the factors that normally control their behaviour and result in malignant tumours.

The most significant damage happens at a young age. One episode of sunburn under the age of 10 increases the Melanoma risk 10 times.

At the moment in the USA one person is dying every hour from skin cancer. In South Africa Malignant Melanoma, the most dangerous form of skin cancer has become the second most common cancer in young Caucasian women. One in seven Caucasians will develop some form of skin cancer in their lifetime.

Although people with very fair skin are more susceptible to sun damage even dark skinned people need to use sunscreens.

How can we combat this problem?

At international government and political level world leaders need to urgently give attention to overpopulation and global warming. Politically this is a very unpopular subject and does not win votes.

At a personal level we can do the following:

  1. Avoid sun exposure, particularly in the middle of the day. Some years ago the teaching was to avoid the sun from 10 am until 3 pm. Our radiation levels are so high that we receive significant exposure virtually from sunrise to sunset.
  2. Use appropriate clothing, including a hat. Common sense tells us that a hat is an essential part of sun protection. Clothing needs to be thick enough to screen the radiation from our skin. Some thin materials like shirts and blouses may allow significant penetration of the sun’s rays.
  3. Apply a sunscreen. A sunscreen needs to be of a high factor, at least factor 30 or over. It also needs to be of a reputable make and to be effective must be reapplied from time to time during the day especially if swimming.
  4. Have a regular skin check. See a plastic surgeon or dermatologist for advice about any skin lesions. Babies need to be checked for brown lesions present at birth. It is advisable to have a full skin check at the end of adolescence. Any change in a skin lesion should be checked immediately. Any lesion that enlarges, or starts to look irregular, or a sore that does not heal needs to checked. If there is a family history of melanoma or if an individual has a large number of moles or more than one dysplastic mole regular skin follow-up is recommended.

ELECTROMAGNETIC RADIAT

30 October 2002