Ultraviolet Rays and Your Eyes
With the alarming numbers of skin cancers being diagnosed around the world, it is increasingly evident that people of all colors need protection from ultraviolet radiation.
Protection should begin as soon as a baby is born and continue throughout life. This is particularly important for people who have fair skin and light eyes. Babies should be kept out of direct sun light and should wear sun protective clothing, including hats and sunglasses. While most sunscreen can be used on infants, it is better to only use a sunblock with zinc and/or titanium dioxide. Apply the sunblock only on exposed skin such as hands and face and only when exposure is unavoidable.
Fashion aside, sunglasses serve an important purpose: protecting eyes from the harmful rays produced by the sun. You're probably well aware of the need to protect your skin from the sun, but it's equally important to protect your eyes.
Ultraviolet Light's Dangers
Ultraviolet (UV) radiation consists of invisible rays from the sun. The three bands of UV light are: UVA, UVB and UVC. UVC rays are of little concern as they are absorbed by the upper atmosphere and do not reach the earth's surface.
UVB rays are the ones that burn the skin and can damage the eyes. Combined with cold wind and snow, UVB has the potential to cause snow blindness (photokeratitis), a temporary (lasting 12 to 48 hours) but painful problem in the cornea of the eye.
Although not all scientists agree, there is some research that suggests that daily exposure to UVB in very bright sunlight over a period of many years may cause cataracts, a gradual clouding of the lens of the eye.
Experts also suspect that the primary cause of eye growths such as pingueculae or pterygia is exposure to UVB rays.
UVA rays are primarily absorbed within the lens of the human eye, though there are no documented disorders of the human eye from UVA. This, however, remains a much debated and researched topic, says the Sunglass Association of America (SAA).
What to Look for When You're Buying Sunglasses
Sunglass standards for lenses place limits solely on UVB and UVA rays, but bear in mind that both the standards and labeling are voluntary, not mandatory. According to these standards, sunglasses must block at least 70 percent of UVB and at least 60 percent of UVA.
To best protect your eyes, look for sunglasses that provide at least 98 percent protection from both UVA and UVB rays. UVC rays are blocked automatically since they are absorbed in the atmosphere and do not reach the earth. Some of the higher-priced products with polycarbonate, glass or plastic (CR-39) lenses can claim to block 100 percent of the UV rays.
Special features of Sun Wear
Determine which special features you need or want. Like cars, sunglasses often have a variety of “extras” from which to choose:
Polarized. Polarized lenses cut reflected glare—when sunlight bounces off smooth surfaces like pavement or water. These can be especially helpful when driving, boating or out in the snow. We have chosen to be an authorized distributor of Costa del Mar sunglasses due to their polarization, UV protection and precise optics. Polarization is unrelated to UV protection, so you still need to ensure UV absorption of the lenses.
Mirror coatings. These thin layers of various 
metallic coatings can reduce the amount of visible light entering the eyes. They are popular in high-glare environments and when combined with the wraparound feature, they can even provide added protection to the skin surrounding the eye area. UV protection, however, is not guaranteed.
Gradient. These lenses are permanently shaded from top to bottom or from top and bottom toward 
the middle. Single gradient lenses (dark on top and lighter on the bottom) can cut glare from the sky but allow you to see clearly below—good for driving, for example, but not as helpful in the snow or at the beach. Double-gradient lenses (dark on top and bottom and lighter in the middle) may be better for sports where light reflects up off the water or snow, such as sailing or skiing.
Photochromic. This is a type of lens that automatically darkens in bright light and becomes lighter
in low light. Although photochromic lenses may be good UV-absorbent sunglasses (again, the label must specify this), it can take a few minutes for them to adjust to different light conditions.
Impact resistant. While all sunglasses must meet minimum FDA standards regarding impact resistance, no lens is truly shatterproof. Plastic lenses are less likely to shatter upon impact than glass lenses. And, 
polycarbonate plastic, used in many sports sunglasses, is even more impact resistant than regular plastic, but scratches easily. If you buy polycarbonate lenses, look for ones with scratch-resistant coatings.
Both Manchester/North York and East York have a large selection of designer sunglasses. Most sunglasses frames are available for prescription lenses.
Shop our convenient online store for eyeglasses and sunglasses in the hottest styles from the top designers. You can even use the FrameFinder Virtual Try-on to find the frame that looks just right. Prescription sunglasses are also available. The online store also offers a large selection of contact lenses. Shop now.
Contact us with any questions you may have or to schedule an appointment.
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