UV radiation bouncing off eyes may cause skin cancer

Updated: Dec 05, 2010, 00:00 AM IST

Sydney: Ultraviolet radiation bouncing off eyes may be causing higher than average rates of skin cancer on the nose.

Benjamin Birt, who recently did his PhD at the Queensland University of Technology, Australia, found that high rates of skin cancer on the sides of the nose could be due to ultraviolet (UV) radiation rays reflected off the eye.

"All surfaces reflect a certain amount of radiation, our eyes are no different," he said.

Birt said the incidence of basal cell carcinoma (BCC), the most commonly occurring skin cancer in sub-tropical climates, was significantly higher on the side of the nose than other parts of the face and neck which were more directly exposed to sunlight.

In order to study the reflection of UV rays off the eye, Birt made a cast of the front surface of his own eyeball, according to a Queensland University release.

He said this shape was then scanned into a model for a ray tracing computer program which simulated rays reflecting off the eye from a range of sun angles.

"I discovered that the curved shape of the eye created a focussing effect, producing UV hot spots on the side of the nose," he said.

"It is a possible explanation as to the high rates of skin cancers found on the nose."

Birt said the reflected rays hit predominately between the tear duct and the bridge of the nose.

"The next step is to study a much greater range of facial shapes and radiation angles than possible with the existing model," he said.

"Good wraparound sunglasses reduce the amount of UV radiation reaching the eye from all angles.