About UV rays
No one is completely safe from the sun. In Canada, sunlight is strong enough to cause skin cancer and premature aging of the skin. The risk of skin cancer today is much greater than it was 20 years ago and continues to increase.
We are exposed to more ultraviolet (UV) rays as the protective layer of ozone around the earth becomes thinner due to the effects of pollution and chemicals.
There are 3 types of UV rays:
- Ultraviolet A rays (UVA) make up most of the sun’s natural light. They can penetrate deep into the skin causing wrinkles and aging.
- Ultraviolet B rays (UVB) are the most damaging to our skin. They are the main cause of sunburns as they are nearly 1000 times stronger than UVA rays.
- Ultraviolet C rays (short-wave radiation) never reach the earth’s surface because the atmosphere filters them out.
UV rays can get through clouds, fog and haze. Water, sand, concrete and especially snow can reflect, and even increase, the sun's burning rays. The risk of skin cancer is higher for people who:
- have light-coloured skin, eyes and hair
- work, play or exercise in the sun for long periods of time
- had several blistering sunburns as a child
- take drugs that make them more sensitive to UV light
Most skin cancers start in areas that are exposed most often to the sun – the head, face, neck, hands and arms.
Last modified on:
09 December 2009
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