Just when you thought you had decoded the label on your sunscreen SPF, PABA-free, water-resistant or waterproof this season, almost all of them display another puzzling abbreviation.
It’s the designation UVA/UVB, indicating protection not only against ultraviolet B rays, which are long known to be harmful, but also ultraviolet A, which is only recently coming under scrutiny.
When health officials first took a serious look at the hazards of sun exposure, back in the 1970s, they focused on UVB rays, which cause sunburn, premature wrinkling, and skin cancer.
The Food and Drug Administration and dermatologists say the hazards of UVB rays are so well documented that a sunscreen’s SPF, or sun protection factor, is based solely on its ability to absorb or block UVB rays.
But in the last few years, scientists have begun to take a closer look at UVA rays, long in the shadow of their sizzling sibling, UVB.
UVA rays don’t pack as much burnpower - it takes 1,000 units of UVA rays to achieve the same suntan as 1 unit of UVB rays - but recent studies show UVA contributes to early wrinkling and possibly cancer, said Dr. Jeffrey Dover, a dermatologist at Beth Israel Deaconess Medical Center.
Dover said UVA’s link to cancer is less well established, though many scientists believe prolonged exposure to UVA may do serious damage. What’s disturbing is that UVA rays reach deeper into the skin than UVB, and health officials need to know more about what this does to the body.
An FDA report four years ago said that in Caucasians, 40 to 50 percent of UVA radiation penetrates the epidermis, or top layer of skin, compared to 10 to 30 percent of UVB radiation. “Protection against UVA radiation is much more important than previously realized,” the report said.
Some scientists are kicking themselves for having ignored UVA rays. Consumers who were soaking in the sun, confident they were protected by high-SPF sunscreens, may have been exposed to a lot of UVA rays.
This is why many health officials are scrambling to talk about UVA protection, even though nobody knows just how much protection is needed and what the dangers may be, beyond extra wrinkling.
“We don’t have a total understanding of UVA,” said Dr. Arthur Sober, associate chief of dermatology at Massachusetts General Hospital. “This is an area that is evolving.”
Future sunscreens may contain a SPF number for UVA protection, though that is at least a couple years away, said John Bailey, director of the office of cosmetics and colors at the FDA in Washington.
“I’m certain we’ll develop a system that measures UVA,” said Bailey. “It will provide a meaningful way to consumers to know how much UVA protection they are getting.”
Meanwhile, more manufacturers are hyping their UVA/UVB protection, though consumers will not know how much UVA block they are actually getting, since standards have not been agreed upon.
“The marketers knew that to go after the savvy consumers, they had to say it had UVA screen, even if it’s small,” said Dover.
He urged consumers to use common sense and not to get frantic if, on occasion, they forgot to use sunscreen. While one major sunburn or chronic scorching does add to cancer risk, he said, “one little sunburn does not make skin cancer.”
In choosing products, dermatologists urge consumers to pick something that has at least a SPF 15. Higher numbers such as SPF 30 will add a bit of insurance, but in many cases people would be paying a lot more for only marginally more sun protection. And sunscreens for adults are fine for children.
Dark-skinned people need little or no sunscreen for daily use because of their skin’s increased melanin, a natural protector.
Dermatologists warn consumers to stay away from a surge of new suntan lotions or tanning enhancers on the market that have no or low SPF numbers. They insist there is no such thing as a safe tan.
The Skin Cancer Foundation said that the chance of developing a melanoma over a lifetime is a staggering 1 in 87, and it is now the most frequently occurring malignancy in women 25 to 29 years of age.
Unless you’re particularly attracted to the smell or texture of certain products, health officials say, you may as well go for the cheapest brand. Just make sure it contains the right SPF level and, if you want it, UVA protection.
Dermatologists say that with a cheaper brand, you may be more likely to apply the product more liberally, which is better protection in the long run.
Prices of sunscreens vary widely, but there’s not much skin-protection difference between a 6-ounce bottle of CVS sunblock lotion or Nantucket Gold, each $4.99, and the more expensive 6-ounce bottle of Banana Boat lotion for $7.15. All offer SPF 15 protection and some UVA protection as well.
Price even range wildly on the 4-ounce bottles marketed to children: With SPF 30 and similar UVA protection, the CVS sunblock for children was $5.99, while Neutrogena or Bain de Soleil costs $9.99.
And for a real bargain, No-Ad brand offers 16 ounces of sunblock, SPF 15 and UVA protectors, for $6.49.
There’s no need to worry about overdoing sunscreen, on yourself or on children. Dermatologists say there is no evidence anyone can be harmed by it.
And Dr. Perry Robins, a dermatologist and president of the Skin Cancer Foundation in New York, said using a sunscreen is more important than whether the product contains UVA blockers.
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