Lately we've become more aware of the hazards of excessive exposure to the sun, the leading cause of skin cancer. In addition to skin cancer, the sun can cause photoaging (premature aging of the skin), which causes wrinkles and a dry, coarse appearance. Unfortunately, increased awareness is not enough - it must also be accompanied with a modification in the way we play and work in the sun.

The effects of the sun are cumulative. Each new instance of damage is added to all the previous instances until the skin breaks down and can no longer cope with the bombardment of the sun's ultraviolet radiation (UVR). The skin's reduced capacity to regenerate damaged cells increases the risk of skin cancer and the certainty of photoaging.

The UVR that passes unfiltered through the ozone layer is responsible for the harmful effects of the sun. Two types of harmful ultraviolet rays reach the earth's surface. Ultraviolet B (UVB) is responsible for sunburning and skin cancer, and is substantially absorbed by the ozone layer. Ultraviolet A (UVA) passes through the ozone layer completely, causes some sun burning, and is primarily responsible for photoaging. A 5% depletion in the ozone layer can result in a 20% increase in the incidence of skin cancer. It is estimated that our area of the world has experienced a depletion of somewhere between 10 and 15%. The primary cause of ozone depletion is chlorofluorocarbons (CFCs), used in aerosols and refrigerants.

Eighty percent of the total skin damage from the sun usually occurs by the age of twenty. There is evidence that severe sunburns during childhood can result in a potentially lethal form of skin cancer, melanoma, in adulthood. Therefore it is imperative that young people are protected from - and educated about - the harmful ultraviolet rays from the sun.

An individual's susceptibility to skin damage from the sun is related to the complexion of the skin and the capacity of the skin to tan. Fair skin is more sensitive to ultraviolet rays, and skin that tans easily is better protected. Use the table at the bottom of this article to identify which of the following skin types best describes you.

Stay One Step Ahead of the Sun

Modern outdoor activities continually bring us face to face with the sun, and some occupations require unavoidable extended sun exposure. Following some simple rules and using a good sunscreen will allow you to enjoy the daylight hours knowing your skin is safe and well protected.

Most good sunscreens protect against both UVB and UVA rays; however, the Sun Protection Factor (SPF) refers only to UVB protection. SPF means that an individual who begins to burn in twenty minutes without a sunscreen will, when using a sunscreen with an SPF of 15, be able to extend this period by 15 times, to 300 minutes or 5 hours. To determine which SPF rating is most suitable, refer to your skin type below.

Skin Types and Recommended Sun Protection Factor (SPF)

* Based on the first 45 - 60 minutes of sun exposure after winter or no sun exposure.

Using Sunscreen

The following are important guidelines for the effective use of sunscreens:

• Apply sunscreen 30 minutes before sun exposure to facilitate binding with skin protein.
• Reapply sunscreens after swimming or profuse sweating (on dry skin).
• Apply sunscreen evenly using approximately 30 ml (one ounce) per application (average body size).
• Cover every exposed area including the scalp of balding men, tops of the ears, sides of the neck, feet and hands.
• Sunscreen lip balms will protect sensitive lips and may even prevent cold sores precipitated by the sun.
• Sunscreens should not be used on infants less than six months old! The best protection is protective clothing or a shady spot.
• All children over six months of age should be protected by a sunscreen with an SPF of 15.

Facts About the Sun and Sun Protection

• The sun's burning capacity is strongest between 11am and 4 pm. If a shady retreat is not available, be sure to use a sunscreen!
• The sun's intensity increases as you near the equator, so be careful when travelling.
• Since up to 90% of the sun's ultraviolet radiation can penetrate cloud cover, burning can occur on a cool, dull day.
• Ultraviolet rays are reflected by dry sand (the beach), fresh snow and any white surface. Even through you may be sheltered, reflected sunlight can burn.
• Forty percent of UVR penetrates water for almost two feet below the surface.
• Progressive exposure reduces the risk of sun damage.
• Wide-brimmed hats protect the ears, forehead and back of the neck.
• Some medication can increase sensitivity to the sun. Ask your pharmacist about the medications you're taking.

Compiled by Ray Gaucher
Westminster West End Pharmacy, Westminster, B.C.
Edited by Megan Stiles
Last Reviewed: September 2001