The sun has been taking a lot of heat lately. From skin cancer and wrinkles to suppression of the immune system, the sun's rays have been linked to a growing list of maladies.
Now, says Kevin Clowers, add to that list such serious eye problems as cataracts.Clowers, an optician and an expert on the effect of solar radiation on the eye, was in Salt Lake City recently running a seminar for Standard Optical.
These days, says Clowers, "if you go outside without sunglasses you're an idiot."
Clowers has a vested interest in sunglass use. He is manager of safety and technical projects for Denver-based Yarrow Distributing, the distributor for Bolle eyewear. But, vested interest aside, Clowers presents some convincing evidence.
"The eyes are radiation receptors," he says, and with the ozone layer deteriorating at a rate of 2 percent a year since 1978, that means higher levels of radiation.
Studies of people who spend a great deal of time in the sun - boatmen on the Chesapeake Bay, for example - have demonstrated a "strong correlation" between sun exposure and cataracts.
"Two-thirds of cataracts are caused by the sun," says Clowers. "We're finding that cataracts are not just a `normal' part of getting old."
Other studies have shown a link between sun exposure and degeneration of the macular portion of the retina - a condition that deprives millions of elderly persons of their central vision.
Compounding the sun's damage, says Clowers, is the radiation emitted by florescent lights. "They leak ultraviolet like you wouldn't believe." And the combination of florescent lights and computer screens is even worse, he says.
"And the wild card in this whole thing," he adds, "is photosensitive chemicals" that make a person more susceptible to the effects of radiation. Such chemicals include sulfa drugs, cyclamates, diuretics and birth control pills.
"We're making more of these compounds all the time; and nobody has any idea what this stuff does when it's exposed to radiation."
Sunglasses can help protect the eye - but not all sunglasses are created equal, he says.
In the sunglass industry, as in the sunscreen industry, there is no compulsory regulation, he explains. Thus a phrase such as "absorbs 100 percent of harmful radiation" may be meaningless.
"It's like when a used car salesman says `Trust me,' " warns Clowers.
Smart consumers will ask to see spectral transmission charts for each pair of sunglasses they try on, he says. The best sunglasses will block out ultraviolet light below 400 nanometers and infrared light above 750 nanometers. "Consumer Reports" is a good source of information about specific sunglasses, says Clowers.
Just because a pair of sunglasses is expensive, he adds, does not mean it does a good job of blocking harmful rays. "Price is not a key."
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Children need sunglasses, too
Children need good sunglasses as much as adults do, says optician Kevin Clowers. But most children's sunglasses "are trash."
In fact, he notes, some children's sunglasses are worse than wearing no sunglasses at all. Not only don't they block out ultraviolet and infrared light, but the darkness of the lenses causes the pupils to dilate, thus allowing even more absorption of harmful rays.
To help prevent future cataracts, parents should invest in children's sunglasses that block out ultraviolet rays below 400 nanometers.
Cataracts form in the crystalline lens of the eye. When a person is born, that lens is clear. But by age 12, if the eyes are not protected from ultraviolet exposure, that lens will already have begun to turn yellow, says Clowers.