UV Rays and Your Eyes
Ultraviolet (UV) rays are invisible rays that are part of the energy that comes from the sun.
There are three types of UV radiation:
UVAUVBUVC
While UVC rays do not pose any threat because they are absorbed by the ozone layer, exposure to UVA and UVB rays can have adverse effects on your eyes and vision. Long-term exposure to these dangerous rays can cause significant damage.
The UV index measures the intensity of UV radiation. This number estimates how long it may take before sun damage might occur. An index of 1-3 signifies a low possibility for UV damage, while an index of 8-10 means a high possibility. It is important to note that UV radiation can also be given off by artificial sources like welding machines, tanning beds, and lasers.
Short-Term Effects
If you are exposed and unprotected to excessive amounts of UV radiation over a short period of time, your eyes are likely to experience an effect called photokeratitis. Photokeratitis is an inflammation of the cornea caused by brief exposure to UV radiation, usually when combined with cold wind and snow.
Much like a “sunburn of the eye,” photokeratitis may be painful and may create symptoms including red eyes, a foreign body sensation or gritty feeling in the eyes, extreme sensitivity to light, and excessive tearing. This is usually temporary and rarely causes permanent damage to the eyes.
Long-Term Effects
Long-term exposure to UV radiation can be more serious. Scientific studies and research out of the U.S. space program have shown that exposure to small amounts of UV radiation over a period of many years may increase the chance of developing a cataract and may cause damage to the retina, the nerve-rich lining of the eye that is used for seeing. This damage to the retina is usually not reversible.
Cumulative damage from repeated exposure may contribute to chronic eye disease as well as increase the risk of developing skin cancer around the eyelids.
Long-term exposure to UV light is also a risk factor in the development of pterygium, a growth that invades the corner of the eyes, and pinguecula, a yellowish, slightly raised lesion that can form on the surface tissue of the white part of the eye.
How to Protect Your Vision
It is not yet known how much exposure to UV radiation it actually takes to cause damage to your eyes and vision. Eye doctors recommend wearing quality sunglasses that offer good protection and a wide-brimmed hat when working outdoors, participating in outdoor sports, taking a walk, running errands, tanning, or doing anything in the sun.
To provide sufficient protection to your eyes, your sunglasses should:
Block out 99 to 100% of both UV-A and UV-B radiationScreen out 75 to 90% of visible lightBe perfectly matched in color and free of distortion and imperfectionHave lenses that are gray for proper color recognition
If you spend a lot of time in bright sunlight, wrap-around frames can provide additional protection from harmful UV radiation. Even if you are wearing contact lenses that have UV protection, you still need to wear sunglasses. UV rays will likely affect the eye tissue that is not covered by the contacts. Your eyes will be more comfortable, too, with most of the bright light blocked.
A Word From Verywell
Remember to provide proper UV eye protection for your children and teenagers. Kids typically spend more time in the sun than adults. Without regular UV eye protection, kids are at risk of developing serious vision damage later in life. Young eyes are especially susceptible to UV-related harm. Unlike an adult eye, a child’s eye cannot effectively filter out UV rays, so more radiation reaches the retina.
While protecting your eyes, you are also protecting the thin skin of your eyelids, which can be susceptible to skin cancer.
