UV and You

On a recent trip to SoHo, I witnessed sunglasses adorned with "100% UV protection" stickers sold for as low as $1.00. And would you believe it, they were also Coco Chanels, Guccis, and Dolce and Gabanas! OK, so the manufacturer labels may have been fictitious, but what about the Ultraviolet (UV) protection? Chances are these glasses really do filter UV rays, though the only way to be certain is to have them measured by an optician. Multiple studies have demonstrated that the price of sunglasses has little bearing on their ability to filter UV light, so don't rush to dismiss the bargain glasses.

UV filtration standards are assigned by continental jurisdiction: Australian, European, or American. The US standard is the lowest (land of the free!) We allow 1% UV transmittance of wavelengths up to 400 nm (Hence the UV 400 stickers), while the Europeans are a little more selective in awarding wavelengths VISAs (up to 380 nm). Our mates down-under fall somewhere in between. There is no enforcement of these standards in the US, so the presence of UV stickers may be misleading.

But what’s so bad about a little sunny delight for the eyes anyway?

UV rays may inflict damage in several layers of the eye cake. Too much UV exposure can cause squamous or basal cell carcinomas to crop up on the eyelids. Likewise, squamous cell carcinoma may develop on the skin of the eyeball (the conjunctiva) and spread onto the cornea. More commonly, chronic UV exposure may result in a growth called “pterygium” to spread over the cornea. Pterygium is Greek for “little wing,” which describes perfectly the shape of this flightless lesion. If these growths are detained on conjunctival territory, they look like little stumps and are fondly named “pinguecula.” Folks who spend their life outdoors are more prone to these conditions: farmers, sailors, the crew of Jersey Shore.

Intense UV exposure may also lead to corneal inflammation (keratitis) and cause a sterile conjunctivitis when the surface cells (epithilium) die off. Welders and DNA lab-workers or those who seek “perma-tans” in their friendly neighborhood spas also fall victim to this ultraviolet infliction.

Sun gazers (usually these folks are high on something, and it's not vitamin D) can damage their retinas with solar rays. The retinas of sober individuals who stare at solar eclipses may also be burned by the sun. The diagnosis “solar retinopathy” is not an eco-friendly energy solution, but rather a transient loss of central vision for one to twelve months!

Finally, some believe excess sun may play a role in the development of cataracts and macular degeneration, though far stronger genetic factors contribute to these entities.

In conclusion, the benefits of sun protection cannot be overstated. Thanks to role models such as Bon Jovi, Paris Hilton, and David Hasselhoff, these accessories are also considered really cool.  Right?