sun exposure

By JANE E. BRODY



This is a plea to all children and teenagers, their parents and teachers, and the doctors who treat them: Please take sun exposure more seriously.

Many parents, if not most, are very conscientious about protecting babies from the sun — as long as the infants are still being carried or are confined to a stroller. But once children become ambulatory, sun protection too often takes a back seat to the myriad challenges of getting out of the house with toddlers or bundling children off to school on time.

Unless sun protection practices are established early in life as inviolable habits, akin to using seat belts in a vehicle, children become increasingly lax as they get older about preventing sunburns that can lead to life-threatening cancers decades later. In a study of 360 fifth graders over three years, Alan C. Geller, director of melanoma epidemiology at Massachusetts General Hospital, and his colleagues found that as the children moved into adolescence, the proportion who “often or always” used sunscreen declined to 25 percent from 50 percent.

And once children reach their teens, sun protection succumbs to burgeoning feelings of independence and invulnerability, as well as the popular belief among teenagers that they look more attractive when sporting a tan. Few seem worried about the chances of developing wrinkled, leathery, blotchy skin decades later as a result. Fewer still seem to know that they are risking cancer.

Yet childhood is the most critical time for avoiding sun-induced harm later in life. As much as 80 percent of a person’s lifetime exposure to skin-damaging ultraviolet rays occurs by age 18. Multiple studies have shown that the more youngsters are exposed to the sun early in life, especially if they suffer serious sunburns, the greater the risk of later developing both superficial skin cancers and deadly melanomas.

The issue of sun protection is all the more important these days because the thinning of the ozone layer has rendered everyone more susceptible to skin-damaging solar radiation.

An Avoidable Risk

For all its marvelous life-giving properties, sunlight can also be damaging and sometimes lethal, even for those who “never” burn, tan easily or have naturally dark skin.

Most babies are born with blemish-free skin. But once exposed to ultraviolet radiation, those destined to become blonds or redheads often develop freckles, a sign of increased vulnerability to sun damage. Even more serious, in white populations, childhood sun exposure increases the risk of developing acquired nevi, or moles, those melanin-rich lesions that can become melanomas.

Unlike superficial forms of skin cancer, called basal cell and squamous cell carcinomas, melanomas are much more serious cancers that arise deeper in the skin and can spread and threaten life before they are detected. And it is not just the light-skinned who are at risk. Melanomas can also develop in people with very dark skin; while it may not burn as easily, darker skin is rich in the pigmented cells in which these cancers arise.

Canadian researchers showed more than a decade ago that routine use of sunscreen by school-age children diminishes their risk of developing moles. The study, directed by Richard Gallagher of the British Columbia Cancer Agency in Vancouver, followed 458 elementary school children over three years. All were initially examined to count and measure how many moles they had.

The children were then divided into two groups. The parents of both groups were asked to keep detailed diaries of their children’s sun exposure during the summer months. One group of parents was given educational materials and a supply of broad-spectrum sunscreen, SPF 30, and instructions to apply it whenever their children were likely to be in the sun for 30 minutes or longer. Each month, the amount of lotion remaining in the bottles was measured as a test of compliance.

The second group of parents received neither the educational materials nor the free sunscreen, though many parents in this group did apply sunscreen to their children on their own. At the end of the study, the number and size of moles on both groups of children was reassessed.

There was no difference in the amount of time the children spent in the sun or in how much clothing they wore. But the children whose parents got the educational information and sunscreen developed fewer moles than the children whose parents did not. And fewer moles, the researchers said, no doubt mean that these children will be less likely to develop melanomas when they grow up.

“This is a true prevention study,” Dr. Gallagher said. “Parents need to know that if they intervene early, they can probably significantly reduce their child’s risk of skin cancer in the future.”

In a 10-year study of 1,621 Australians ages 25 to 75, Adele C. Green of the Queensland Institute of Medical Research and colleagues found that those who used sunscreen daily on their head and arms developed half the number of melanomas as those who used it less often.

Helpful Programs

In an interview, Mr. Geller, a lecturer on health at the Harvard School of Public Health, cited several programs that could help change the sun protection practices of children. One is called SunWise, created for schools by the Environmental Protection Agency, which includes a “toolbox” of instructional materials that can help teachers incorporate sun protection messages into various subject areas, like math, social studies and physical education.

Another is Pool Cool, developed by Karen Glanz, professor of epidemiology and nursing at the University of Pennsylvania, and designed for children ages 5 to 10. Lifeguards and parents at swimming pools are taught about the use of sunscreen, shirts and hats to reduce sun exposure.

“A T-shirt has an SPF of 7 or 8,” Mr. Geller said. “A shot-glass amount of sunscreen should be applied to all exposed skin, including the ears, back of the neck and top of the feet, which are often forgotten.”

In Australia, where skin cancer has long been epidemic, a “no hat, no play” policy as part of a broad-based emphasis on sun protection has made the country one of the first in the world in which skin cancer incidence is declining, Mr. Geller said.

He also urged pediatricians “to take sun exposure more seriously” and to emphasize the importance of sunburn prevention at every visit with children. And, he said, sunscreen should be made readily available at pools and beaches.

“We should be applying the lessons learned from tobacco, using clever public service ads and more emphasis in schools of the downsides of sunburn,” he said. “Kids need to hear messages about the impact of sun protection multiple times from multiple sources.”