When we think of Summer, images of beaches, theme parks, and outdoor sports and activities come to mind. While getting out of the house and doing things outside is generally considered to be healthy, there are risks involved, one of which is exposure to the dreaded UV light.
Ultraviolet (UV) light refers to the region of the electromagnetic spectrum between visible light and X-Rays with a wavelength between 10 and 400 nanometers. It is not visible to the human eye because it has a shorter wavelength and higher frequency than the light our brain perceives as images.
There are three main types of UV radiation. UV-A (320-400nm) has the longest wavelength and is the least harmful. UV-B (290-320nm) causes sunburn with prolonged exposure along with an increased risk of skin cancer and other cellular damage. UV-C (100-290nm) is extremely harmful, but is absorbed by the Earth’s atmosphere and does not pose a threat.
The eyes are particularly susceptible to the effects of UV light. Excessive exposure over a short period of time can cause photokeratitis, like a sunburn of the eye. Photokeratitis can be painful and causes red eyes, watering and foreign body sensation or a gritty feeling. Fortunately, these symptoms are usually temporary and rarely cause permanent damage to the eyes.
Longer exposure to UV radiation increases the risks of eyelid skin cancers, cataracts, and macular degeneration. Therefore, when you spend time outdoors wear quality sunglasses that offer UV protection and a hat or cap with a wide brim. Also, certain contact lenses can provide UV protection.
The American Optometric Association recommends sunglasses that:
- Block out 99-100% of both UV-A and UV-B radiation
- Screen out 75-90% of visible light
- Have lenses that are perfectly matched in color and free of distortions and imperfection
- Have lenses that are gray for proper color recognition
- Are impact resistant if used with potentially hazardous outdoor activities
- Are mounted in a wraparound frame if you spend a lot of time outdoors
One of the joys of living in Florida is being able to participate in outdoor activities year round. Let’s all get outside and have fun, but don’t forget to take the proper precautions.
By: Edward Attaway, O.D.