Ultraviolet (UV) Radiation & Your Eyes
Summertime is when most of us think about how the sun effects our health. Many of us take precautions to protect our skin from the harmful rays of the sun. You may avoid being outside during peak ultraviolet (UV) radiation hours, use sunscreen, cover up with clothing, or stay in the shade when possible. But do you think about how the sun effects your eyes? We hope the following information, on how UV exposure can damage your ocular health, will make you think about taking extra precautions to protect your eyes.
Ultraviolet (UV) Radiation UV is found in sunlight and is a form of electromagnetic radiation with high frequency waves. The biological effects of UV radiation depend on the particular wavelengths.
UVC - Although it is the most harmful solar radiation, UVC is absorbed by the earth’s atmosphere or ozone (light blue band) layer, and does not harm your eyes.
UVB - is only partially blocked by the earth’s atmosphere and can affect the epidermis, or outer layer, of the skin. This results in sunburn, blistering, or possibly skin cancer. UVB exposure can damage the outer layer of your eyes, causing severe irritation, light sensitivity, and excessive tearing. The cornea (#1) and the lens (#2) absorb the UVB radiation.
UVA - UVA rays are the most common kind of ultraviolet energy that reaches the earth and is the one that causes tanning and aging of the skin. Because it penetrates more deeply, it affects the inner layers of the skin and eyes, including the cornea (#1), lens (#2), and retina (#3)
Who's at risk
Children and teens are at a greater risk because they spend more time outdoors, receiving three times the annual sun exposure compared to the average adult. The crystalline lens in a child’s eyes does not effectively filter UV rays, leading to more radiation reaching the retina. Because young eyes are more susceptible to UV-related harm, and UV damage is cumulative, it may lead to serious eye health problems in the future.
UV radiation is present year-round, during every season, no matter the weather. UV levels are at their greatest between the hours of 10 a.m. and 2 p.m. In addition to direct exposure UV rays can reflect off a variety of surfaces. This reflected UV light is just as damaging as direct UV. Examples of different surfaces and the percentage of UV light they reflect include:
The Vision Council
Ocular Conditions resulting from UV exposure:
Photokeratitis: (foh-toh-ker-uh-tahy-tis) inflammation of the cornea caused by exposure to ultraviolet radiation (aka: Ultraviolet Keratitis, Snow Blindness)
Photokeratitis is like having a sunburned eye. It could be the result of spending a day at the beach, on the water, or the ski slopes without the proper eye protection. The overexposure to UV rays causes an inflammation to the thin surface layer of the cornea — the clear front window of the eye — and the conjunctiva, which is the clear tissue covering the white part of the eye and the inside of the eyelids. Also, like a sunburn on your skin, photokeratitis is not usually noticed until well after the damage has occurred.
Other sources of photokeratitis include Welder’s flash, tanning beds, and viewing a solar eclipse without proper eye protection. Symptoms include pain, redness, blurred vision, tearing, gritty feeling, light sensitivity, or general pain of the eyes. Photokeratitis is usually a temporary condition, but does require treatment with antibiotic and artificial tears to help it along. Cold compresses can also be used to help with the discomfort.
Pinguecula: { pĭng-gwĕk′yə-lə } a small yellowish elevation on the whites of your eye, situated near the inner or outer margins of the cornea.
Pinguecula is a raised growth on the conjunctiva, the clear membrane that covers the white of the eye just outside of the colored part. It’s usually on the side of the eye near your nose, but can happen on the other side too. This presents as a white or yellow raised area or bump. This growth does not go away, but can be treated with special eye drops, if it becomes red or swollen. When a
pinguecula continues to grow it may reach the cornea and become a pterygium.
Pterygium: ( tuh-rij-ee-uh m ) a fleshy mass of thickened conjunctiva that grows over part of the cornea usually from the inner side of the eyeball, causes a disturbance of vision (aka: Surfer’s Eye)
Abnormal growth of tissue on the conjunctiva (the clear membrane that covers the white of the eye) and the adjacent cornea (the clear front surface of the eye). A pterygium is a growth of fleshy tissue (with blood vessels) that may start as a pinguecula. It can remain small or grow large enough to affect your vision, and lead to scarring of the cornea, which could lead to permanent vision loss. If the pterygium is progressing, surgery may be required to remove it to save your vision.
Cataract: ( kat-uh-rakt ) a clouding of the lens of the eye or of its surrounding transparent membrane that obstructs the passage of light
A cataract is the result of changes to the clear lens inside the eye. As the lens becomes cloudy, discolored, or irregularities form in the center of the lens, the light entering the eye will become blurry or distorted. Research shows individuals who are exposed to more UV radiation develop more severe cataracts at an earlier age. Symptoms include cloudy or blurry distance vision, altered color perception, problems with glare, difficulty reading fine print, poor night vision and frequent changes in glasses prescriptions. Removal of cataracts is done by surgery
Macular Degeneration: damage to the central portion of the retina, resulting in a loss of sharp vision.
Macular degeneration is a leading cause of legal blindness in the U.S. The macula (central part of the retina), provides the clear, sharp vision needed for everyday tasks such as reading, writing, driving and other visually demanding activities. Individuals with macular degeneration lose their central vision and cannot see details (at distance and near) or experience a distortion of vision, such as seeing "wavy" lines.
Prevention is Key:
In the words of Benjamin Franklin “an ounce of prevention is worth a pound of cure”. That certainly holds true when it comes to protecting your eyes from Ultraviolet radiation. Consider the following facts before heading outside.
Most American adults look at comfort, price and style when buying new sunglasses, less than 30% prioritize UV protection.
Sunglasses should be worn when outside year-round, not just in the summer.
Your glasses lenses (whether clear prescription or sunglasses) should block 99 to 100 % of both UV-A and UV-B radiation.
Dark sunglasses without proper UV protection can be worse than wearing no sunglasses because they cause the pupils to dilate, which increases exposure to unfiltered UV.
UV radiation is present on cloudy days and sunny day
Wear wide-brimmed hats and caps can block up to 50% of UV rays from the eyes.
Avoid the sun during the hours between 10am-4pm
Disclaimer:
Thank you for taking the time to read Ultraviolet (UV) Radiation & Your Eyes. If you have any questions please send us a message,
It is designed to be educational for the general population and not taken as personalized medical advice,
Most importantly remember to schedule your annual eye examination.
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