You may remember to slap on the sunscreen whenever you go outdoors to avoid skin cancer, but do you take as much care to slip on your sunglasses? Every time a UV ray from the sun penetrates your unprotected natural lens, the clear surface at the front of the eye, it may cause cellular damage in the retina and cornea behind it, which over time could cost your sight.
The College of Optometrists’ clinical adviser Susan Blakeney explains: “We need to protect our eyes against radiation, specifically the UVA and UVB rays which can cause damage to our eyes and to the structures surrounding them, including our eyelids and the back of the socket. Although our eyes can absorb some UV rays harmlessly, they are particularly vulnerable to radiation as the lens is transparent.”
She warns: “This is especially true for children as they tend to spend longer outdoors than adults and as their pupils are naturally larger – these shrink with age – thus letting in more sunlight. Yet many people don’t realise that just because glass has a tinted colour it may not offer any defence against UV light. Instead, the dark colour lessens the need to squint in sunshine, allowing our pupils to open wider and let even more rays in.”
So what does UV light do to the eye? Helen May, RNIB’s eye health adviser and optometrist explains: “Sun damage can either be accumulative or acute. For example, long-term exposure to UV can cause malignant tumours on eyelids. It can also cause gradual damage to the cells of the cornea and retina. This builds up over time, especially in those who work outdoors.
“We also know that this type of exposure may contribute to certain types of cataracts, the clouding or opacification of the natural lens in the eye which needs surgery to repair. And it may contribute, as one factor of several, to macular degeneration, the most common cause of age-related blindness.”
Direct sunburn on the cornea or retina could happen after a long day on a Mediterranean beach or even in the UK on a very hot day
All these conditions are most likely to be spotted by an optician, a good reason to have the NHS-recommended regular two-yearly checks. But if you suffer acute damage, you’ll know it immediately, says Ms May. “Direct sunburn on the cornea or retina could happen after a long day on a Mediterranean beach or even in the UK on a very hot day. They also happen to skiers and sailors, as reflections from snow or water intensify the sun’s effects.
“You’d certainly know it fast. Your vision would become blurred, the eye very painful, red, irritated – you should seek immediate attention from an eye specialist if it happens.”
Beware “sun-gazing” too, warns eye surgeon Professor Dan Reinstein of the London Vision Clinic. “Observing an eclipse of the sun without specific appropriate protection can lead to instantaneous and severe visual loss from macular damage, which is permanent and irreversible. Even looking at one of those beautiful huge red suns over the horizon at sundown for more than a few seconds can cause permanent damage to the macula.”
Yet, prevention is so easy, says Ms Blakeney. “Always use good-quality, dark sunglasses with the CE mark [a European standard of UV protection] that means they should allow no more than 5 per cent of UV rays below 380 nanometres [a measurement of light] to get through. You can also look for the British kite mark 1836:2005 and some may carry a UV400 label.
“Most prescription glasses and contact lenses now have a built-in UV filter, but your optometrist can arrange for the lens to be coated, whether they are single, bifocal or varifocal. Wraparound sunglasses are the best style as they protect the side of the eyes, and a hat with a floppy brim will protect your eyes and the area around them.”
COUNTERFEITING
CHEAP SUNGLASSES ARE SUCH A SHADY DEAL
Everyone loves a bargain, but if something seems too good to be true – it usually is.
There are plenty of cheap sunglasses around and some are genuine discounted fashion lines; so how do you spot the fakes?
Sometimes it should be easy. A beach seller touting “designer” brands, which normally retail at around £200 a pair, for just ten euros is unlikely to pass a lie detector test.
If you live in the UK and buy a pair of “luxury” sunglasses for a knockdown price in a Hong Kong market, the vendor will always offer you a money-back guarantee to seal the shady deal.
Sad to say, but it’s easier to pass off fakes online. The item pictured may be genuine, but the sunglasses dispatched are definitely not and the seller can disappear into cyberspace without trace.
And beware the counterfeiters target the most popular styles which carry over from season to season.
Not to worry – after all it’s just a bit of fashion fun? Not true. Cheap copies of designer sunglasses could cost you dear. Genuine brands have lenses which carry the European CE mark and absorb UV up to 400 nanometres to protect your eyes.
But shop at a market abroad or even online and you might find some with a “CC” logo and coloured glass for lenses.
Even if you find cheap glasses with a CE mark, check the fit. Flimsy arms or bridge will make them more likely to slide about, reducing their protection, regardless of lens coating.
And some dark glasses are too tinted for safe driving. The AA warns that “filter category 4” lenses transmit between 3 per cent and 8 per cent of light, and are not suitable for driving at any time.
Sunglasses with these lenses should, by law, be labelled “Not suitable for driving and road use”, but cheap imports may not carry any such warning.
