By now, most Americans know that the sun’s ultraviolet (UV) radiation is the major cause of skin cancer — the most common of all cancers. What many people don’t realize, however, is that UV and other types of radiation can severely damage the eyes.
What is UV radiation?
These powerful, invisible rays are the most dangerous parts of sunlight:
Are the highest-energy UV rays with the potential to cause the most severe damage to eyes and skin. Although the atmosphere’s ozone layer blocks almost all of these rays, continued depletion of this protective layer may allow more UVC rays to reach the earth’s surface and cause serious health problems.
Have slightly longer wavelengths and lower energy than UVC rays. Although they are also filtered by the ozone layer, some rays reach the earth’s surface. UVB radiation is responsible for the production of the skin-darkening pigment called melanin that causes your skin to tan.
Are closer to visible light rays. Although they have lower energy than UVB and UVC rays, they can pass through the cornea and reach the lens and retina inside the eye.HEV light, or Blue Light (High-Energy Visible Light)
From the sun is thought to contribute to cataracts and macular degeneration. These visible radiation rays have longer wavelengths and lower energy than UV rays, but they penetrate into the eye and cause retinal damage.
While most of our HEV exposure comes from sunlight, man-made, indoor sources of blue light include:
- Display screens of computers, electronic notebooks, and smartphones
- LED and fluorescent lighting
- Flat-screen televisions
Although the amount of blue light emitted from these devices is low compared to the sun, Americans spend a lot of time looking at these screens at close proximity.
How do these rays damage eyes?
The Skin Cancer Foundation reports: “Eyelid skin cancers, including basal cell carcinoma, squamous cell carcinoma, and melanoma, account for 5 to 10 percent of all skin cancers. Most occur on the lower lid, which receives the most sun exposure.”
Overexposure to UVA radiation has been linked to the development of certain types of cataracts, the most common cause of treatable blindness.
Research suggests cumulative damage to the retina from UVA and HEV rays may play a role in the development of age-related macular degeneration.
UVB rays also contribute to pingueculae and pterygia, unsightly growths on the eye’s surface that damage the cornea and distort vision.
UVB rays can cause photokeratitis, or “snow blindness,” a painful inflammation of the cornea, which causes temporary vision loss for up to 48 hours.
UVB rays cause skin discolorations, wrinkles, and premature aging of the skin around the eyes.
Who is more susceptible to UV damage?
People with light eyes and fair skin have the highest risk for skin cancer and certain eye diseases because they have less melanin to protect them, but everyone requires adequate sun protection.
Individuals taking certain medications that increase the body’s sensitivity to UV and HEV radiation are more vulnerable. These drugs include:
- Sulfa drugs
- Birth control pills
People who spend a lot of time around snow, sand, and water –such as skiers, surfers, lifeguards, and fishermen — are more at risk for damage. UV is more intense at high altitudes, and snow reflects back about 80 percent of the sun’s rays, which means it hits your eyes a second time. Water and sand also reflect UV rays, with the greatest concentrations found from 10 a.m. to 2 p.m.
Remember that you can still be exposed to UV radiation on overcast days. UV is invisible radiation, not visible light, and can penetrate clouds.
How can I protect my eyes while enjoying outdoor activities?
Sunglass are your primary defense against harmful solar radiation. But as Mayo Clinic explains, “The color and degree of darkness sunglasses provide have nothing to do with the sunglasses’ ability to block UV rays.”
- Choose wraparound sunglasses or close-fitting sunglasses with wide lenses to protect your eyes from sunlight coming from above and beyond the periphery of your lenses.
- Select sunglass that block out 99 to100 percent of both UVA and UVB radiation and screen out 75 to 90 percent of visible light. They should also protect you from HEV light.
- Choose polarized lenses to eliminate glare while driving or in the snow or by water.
- Never look directly at the sun. This can cause solar retinopathy, which is damage to the retina.
- If you wear contact lenses that offer UV protection, add sunglasses to maximize protection.
- Remember to apply liberal amounts of sunscreen, seek shade between 10 a.m. and 4 p.m., and wear a hat with at least a 3-inch brim to help block UVB rays from your eyes and eyelids.
- Everyone needs UV protection all year round, so equip children and seniors with UV-blocking sunglasses and broad-brimmed hats.
- The American Optometric Association advises that you see your eye doctor every year for a comprehensive examination to monitor your solar radiation protection needs.
At Sealy Eye Center, our eye care specialists use the latest technology to diagnose and manage the eye conditions associated UV radiation damage. Please call Sealy Eye Center at (888) 701-7487 and schedule your exam today.