What is UV Radiation?

Most people are aware of the danger of sun exposure to the skin but many do not realize that exposure to the sun is dangerous to our eyes and our children’s eyes. This type of sun exposure that causes damage is called ultraviolet or UV radiation.

There are three types of UV radiation. There are UVC rays, which are the highest energy UV rays. This type of UV radiation could potentially be the most dangerous but fortunately, the ozone layer blocks virtually all UVC rays. Though unfortunately, the ozone layer is thinning, which can cause more UVC rays to reach the earth.

UVB rays have lower energy than UVC rays and are filtered partially by the ozone layer, but some still reach the earth’s surface. UVB rays are the rays that cause a suntan and/or sunburns.

UVA rays are closer to visible light rays and have lower energy than UVC and UVB rays. But UVA rays can pass through the cornea and reach the lens and retina inside the eye. Overexposure to UVA radiation has been linked to the development of certain types of cataracts and may play a role in development of macular degeneration.

UV levels are greater when the sun is high in the sky, typically from 10 a.m. to 2 p.m. When the sun is overhead at noon, the level of UV exposure is 10 times greater than that at either 3 hours before or 3 hours after noon. UV levels are also greater in wide-open spaces, especially when highly reflective surfaces are present, like snow, sand and water. UV exposure can nearly double when UV rays are reflected from the snow. There is less risk of UV exposure in urban settings, where tall buildings shade the streets.

UV levels are highest in the spring and summer and the least intense in the winter. However, fresh snow reflects 85% of the UV rays compared to only 1 or 2 % from grass.

Surprisingly, cloud cover does not affect UV levels significantly. Your risk of UV exposure can be quite high even on hazy or overcast days.

How can UV Radiation damage our eyes?

Everyone, even children, is at risk for vision loss caused by UV radiation. Any element that increases your exposure to sunlight, including certain prescription drugs that increase sensitivity to UV light, can increase your risk of eye disorders

Without proper eye protection, UV radiation can cause a temporary, but painful burn to the surface of the eye
(cornea), similar to a sunburn of the skin.

UV radiation can also cause pterygia and pingueculae, (you don’t need to know how to pronounce them..but you should know how to avoid them) which is an abnormal yellowish growth on the corner of the eye near the nose. Cataracts, a clouding of the lens can also occur as well as macular degeneration, which is an eye disorder that causes damage to the central part of the retina.

According to the National Cancer Institute’s SEER database, an estimated 2,390 men and women were diagnosed, and 240 died from, cancers of the eye and orbit in 2008. The thin and delicate structures and greater lifetime exposure to the sun than any other part of the body, the eye and surrounding areas are particularly prone to cancers.

How can we protect our eyes and our children’s eyes from these harmful rays?

To best protect your eyes from the sun’s harmful UV rays, always wear good quality sunglasses when you are outside. Look for sunglasses that block 100% of the UV rays and provide a clear statement about how much UV radiation is blocked. If you are unsure about the level of UV protection your sunglasses provide, take them to your eye doctor or optician for an evaluation.

Also look to see if the glasses meet ANSI and/or ISO standards for traffic signal recognition, which means that the lenses permit good color recognition, especially for tasks such as discriminating red from green traffic signals.

To protect as much of the delicate skin around your eyes as possible, try at least one pair of sunglasses with large lenses or a close-fitting wraparound style.

Sunglasses should be worn in the shade because UV rays can be reflected from buildings, roadways, and other surfaces. Sunglasses should also be worn in winter because fresh snow can reflect 80% of UV rays. Sunglasses should also be worn even if your contact lenses block UV rays because the UV blocking contacts shield only the part of the eye under the lense.

Because experts say that as much as 80 % of our lifetime exposure to UV rays occurs by age 18, it is important to protect your child’s eyes from UV rays.

Make sure that your child wears sunglasses when going outside. Your child’s sunglasses should also absorb 99 to 100% of the UV rays, fit well, have lenses that are large enough to shield the eyes from most angles and fit your child’s lifestyle.

Wearing a hat can cut the amount of UV rays that reach the eyes by half.

Have fun outside but remember, PROTECT YOUR EYES!!!