Many people are today aware of the dangers to one’s health that exposure to the sun rays for extended periods of time can have. Skin cancer is probably the most prominent of such conditions. Fewer people though are aware of the risks that the sun has on their eyesight. What makes it even more dangerous is the fact that you do not have to be looking directly at the sun for this damage to start to take shape. This is because the damage to the eyes is less to do with light itself and more to do with the radiation from ultra violet rays
The sun generates not only heat but also radiation. The most harmful radiation rays known as UVC are filtered before they reach the earth. UVA and UVB are the ones that penetrate the earth’s atmosphere with UVB being the more dangerous of the two as it can alter the DNA of living organisms. UVA is the one responsible for both skin ailments and vision problems. Matters are not helped by the gradual depletion of the earth’s ozone layer which serves as the planet’s protective sheath from solar radiation.
Unfortunately the damage caused to the eyes by ultraviolet radiation is permanent. Thus, avoiding exposure is the best approach. Cornea injury, retina-iris damage, cancers of the eyelid and eyeball, development of cataracts are all potential effects to UV exposure. The unfortunate thing about eye damage is that the effects might take years to actually show and by the time one realises it, there might be very little one can do to reverse the effects.
One of the most effective ways to counter the effects of this radiation is by the use of sunglasses. But in wearing sunglasses, it is important for one to understand the particular circumstances during which they should be wearing sunglasses. For instance, and contrary to many people’s expectations, the warmest climate is not necessarily the most dangerous environment as far as ultraviolet radiation is concerned
The warm and green areas in the tropics even though experiencing much higher temperatures than the areas closer to the poles, do not pose as much a danger to eyesight. The reason for this is one: surface radiation. And this is pegged to the frequency and extent of snow fall since snow reflects more UVA radiation than almost any other surface.
It is highly unlikely that anyone will want to or be able to gaze directly into the sun for extended time periods. However, it is difficult to completely avoid looking at a snow covered surface, more so if the snowfall covers a large area and is regular. Sunglasses that have the ability to block UV radiation during such times would be invaluable.
High altitudes are also a high risk environment for UV radiation due to the thinner atmospheric protection. But sunglasses are not just important in protecting against UV radiation. The impact of minuscule dust particles in environments that characterized with strong wind can lead to corneal abrasion in the long run.
Sunglasses should not only be a fashion statement but are also a vital tool for ensuring eye health.
Jason Thompson is an expert in polarised sunglasses. Find out more at https://www.eyewearcanada.com/sports-glasses/activity/safety-ansi