Skin cancer prevention is successful only if the causative agent--sunlight--is restricted throughout a person's life. Sun damage to the skin accumulates over time, so that even a brief exposure adds to the lifetime total. UV rays bounce off sand, snow, and other reflective surfaces; about 80 percent can pass through clouds, and the rays can reach down into three feet of water. The people most motivated to adequately protect themselves from sun are those already experiencing the aging and cancer-producing effects of solar radiation. Unfortunately, this is long after the time preventive efforts are likely to be very effective.
Ultraviolet rays reach the earth in two wavelengths: UVA and UVB. UVB more readily causes redness and sunburn. UVA rays penetrate more deeply and, therefore, damage elastic tissue, augment the carcinogenic and burning properties of UVB, and affect the skin's immune response. Everyone has heard that tanning parlors can be dangerous, so some tanning parlors have switched to sun lamps producing primarily UVA rays, with the erroneous idea that these rays are less likely to cause burns and skin cancer. The consumer should also know that the intensity of the UVA received in a tanning parlor is twice that received while sunbathing at noon on the beach in the summer; thus, the potential for harm is great.
Many individuals who patronize tanning parlors think the tan they receive by artificial means is protective; this is a misconception, as it has been shown that on the average, this tan provides a sun protection factor (SPF) of only 4. People who are fair-skinned and normally burn without tanning when exposed to the sun will have the same response when frequenting tanning parlors.
Some studies show that the sunburn reactions of redness and itching appear to be more common in women taking oral contraceptives. Other commonly taken medications such as Sulfa products (Septra, Bactrim, Gantrisin) and Tetracycline can also produce photosensitivity reactions, as can perfumes and other skin products. Eye damage in the form of corneal burns, retinal damage, and possibly cataracts is possible. These ocular side effects are not prevented by closing the eyes; protective eye wear is mandatory. The nausea some sun worshippers experience has been associated with failure to use such eye wear. Increased risk for developing malignant melanoma is the most critical consequence of excess UVL, as melanoma is the most virulent of all skin cancers.
Half of the average person's lifetime sun exposure occurs before the age of 20. Actinic keratosis, a pre-cancerous condition, appears even in people in their early 20s who have spent too much time in the sun with inadequate protection, so it's important to learn and perform skin self-exam. Look for the pamphlets in the Health Center that show the ABCDs to help you identify an abnormal growth.
- The single most effective preventive method is avoidance of the sun.
- Limit the amount of time you spend in the sun, avoiding the peak hours from 10 a.m. to 3 p.m.
- Seek the shade.
- Cover up with protective clothing, including a broad-brimmed hat (recent evidence shows this to be much more effective than using sunscreen.)
- Wear sunscreen with SPF of 15 or greater. This will help prevent basal and squamous cell cancers but apparently is not effective in preventing melanoma.
- Avoid tanning parlors and artificial tanning devices.
- Perform regular skin self-examination; consult a physician if you see or feel a suspicious area.
Helen Balgooyen, R.N.C.
