The information ‘UV’e been waiting for…
Summer is well and truly underway and we’re all enjoying the longer days, warmer temperatures, and sitting in the garden with the barbeque burning away. Nowadays, people are quite clued up on the risks of sun damage when it comes to severe sunburn and skin cancer, and sun cream is a staple item for British summertime. Not everyone, however, is quite as aware of the sun’s impact on your eyes – not just in the present, but how the damage can manifest itself over time. Exposure to the sun’s ultraviolet (UV) rays can result in cataracts, macular degeneration, pterygium, pingueculae, and photokeratitis. There are actually three different types of UV rays which can all cause different types of damage to your eyes and skin. Aside from applying sun cream, one way to prevent damage is to wear UV protection sunglasses. We’re going to discuss all the potential impacts of the sun on your eyes, and how you can prevent any optical damage whilst out in the sun this summer.
A-Z of UV
UV rays (or radiation) can penetrate cloud cover, so you’ll need protection from the sun even on cloudy days. The three types of UV radiation are UVC, UVB and UVA. UVC rays are the highest energy rays, and are therefore the most damaging to your eyes. The ozone layer typically blocks most of these rays but, with climate change an ever-growing problem in today’s world, the ozone layer is diminishing. This means that more UVC rays are getting through to us, potentially causing severe health problems. As time goes on, the effects of the lack of ozone combined with more UVC rays will become apparent. For now, we can just invest in a good pair of wraparound sunglasses and keep liberally applying sun cream.
UVB rays are partially filtered out by the ozone layer but some still reach us. It’s these rays which can give our skin a nice bronze glow but, if we’re exposed to too many UVB rays, they can also cause sunburn and increase our risk of skin cancer. In terms of damage to our eyes, UVB rays encourage the development of several eye conditions; pinguecula, pterygium, and photokeratitis.
Photokeratitis is essentially sunburn of the cornea, symptoms of which include a burning sensation, red eyes, watery eyes and blurry vision. The effects are only temporary and should clear up within a couple of days, but the impaired vision that comes with it can make it unsafe to drive for those two days. Overexposure to UVB rays can also result in pingueculae, non-cancerous lumps on the sclera – the white part of your eye. A symptom of this condition is dry eyes as the tear film is disrupted by the lump on the sclera, which can be treated with lubricating eye drops. Pinguecula is a similar condition to pterygium, which is also a lump that grows on the sclera. Being exposed to bright sunlight is the main cause for its development and symptoms are itching, burning, and a foreign body sensation. It can also change the eyeball’s natural curve, causing astigmatism and impairing vision. The cornea absorbs 100% of UVB rays, making them particularly damaging when it comes to these three eye conditions.
UVA rays have much lower energy than UVB and UVC rays, but they can pass through the cornea to reach the lens and retina, bringing a whole host of new problems with them. Too much UVA radiation has been proven to encourage cataract development (20% of cataract cases are caused by UV overexposure) and new research links it to macular degeneration too. It is the blue light from the solar spectrum which contributes to the development of macular degeneration, so blocking this light from your eyes is crucial. While cataracts are easily treatable, macular degeneration is a condition which affects your central vision and, if left too long before being treated, can permanently impair your vision.
UV protection sunglasses
Thankfully, in the UK and Europe, standards on sunglasses sold are really strict. To meet guidelines, all manufacturers must ensure that their lenses block between 99 and 100% of UV radiation. This prevents almost all UV rays from reaching your eyes and causing the aforementioned eye conditions. You should also consider investing in sunglasses with polarised lenses. These have a chemical film coating on the lens to reduce glare, where light is reflected off water or a solid surface. The polarised lenses reduce this effect and improve depth and colour perception. While the polarisation doesn’t affect the UV light absorption through the lens, it will help your overall vision while wearing sunglasses.
Similarly, the best lens colours for sunglasses are grey or brown, as these allow you to perceive colours correctly, which other lenses – for example, yellow-tinted – may not. However, the colour or darkness of the lens is no indication of its UV protection levels, so don’t rely on this alone! Studies conducted at Aston University determined that even with a pair of sunglasses which block 100% of UV rays, light came still come into contact with your eyes around the side of the glasses. For this reason, you should consider glasses with a wraparound style, allowing as few UV rays as possible to creep round the edges.
UV risk factors
There are certain settings and situations which increase the risk of UV exposure, and therefore increase the risk of damage to your eyes. First and foremost – as most people are aware – the time of day has a crucial role in how much UV radiation you are exposed to. Between 10am and 2pm, the sun is at its highest position in the sky with the strongest rays. Try and stay in the shade or inside during these hours, for both your skin and your eyes. Similarly, the closer you are to the equator, and the higher your altitude, can increase your UV exposure too. The setting around you is also particularly important as the rays can reflect off surfaces like snow and sand – sometimes doubling your exposure to UV radiation.
As well as sunglasses, you can also wear a wide-brimmed hat to cast a shadow over your eyes and protect them from the sun. Some people think that if they have darker skin and eyes, they are exempt from sun damage. When it comes to eyes, this is simply not true – everyone’s risk of eye damage from UV rays is the same, which is all the more reason to invest in a good pair of sunglasses.
Be extra vigilant with your eyes this summer to protect yourself from a number of eye conditions and preserve your sight for years to come. You’ve only got one set of eyes, so remember that they’re just as vulnerable as your skin in the sun.