 THURSDAY, May 12, 2016 -- The front windshield of your car probably shields you from the sun's UV-A rays as you drive, but the same may not be true for side windows, a new study finds. Experts have long known that prolonged exposure to ultraviolet A (UV-A) rays can raise the odds for skin cancer and cataracts. To find out, Dr. Brian Boxer Wachler, of the Boxer Wachler Vision Institute in Beverly Hills, analyzed the ultraviolet protection provided by the glass in 29 cars from 15 different automobile manufacturers. While windshields blocked the vast majority of ultraviolet (UV) radiation from the sun, car door windows offered varying levels of protection from the rays that are tied to cataracts and skin aging. While windshield windows tended to offer good protection against UV-A, protection was lower and inconsistent for the side windows of cars, the study findings showed. The study found front windshields blocked an average of 96 percent of UV-A rays, compared to 71 percent for side windows. Overall, only 14 percent of the cars offered a high level of side-window UV-A protection, the research revealed. Because drivers in the U.S. have their left side exposed to sunlight, UV rays have been blamed for the increased number of cataracts and skin cancers that occur on the left side, Boxer Wachler writes in JAMA Ophthalmology. He believes that, based on the new data, "automakers may wish to consider increasing the degree of UV-A protection in the side windows of automobiles." "This is a great option for those who have older cars or cars that don't have the protection already built in," she said. SOURCE: bit.ly/1s2rp6t and bit.ly/1XnFyHu JAMA Ophthalmology, online May 12, 2016.
– Ever gotten a sunburn while driving with the windows up? A new study explains why. Most vehicle windshields block harmful UV-A rays—the kind that raise the risk of everything from cataracts to skin cancer—but your side windows might not, says Brian Boxer Wachler of California's Boxer Wachler Vision Institute. He tested 29 cars made from 1990 to 2014 and found that front windshields blocked 96% of UV-A rays, reports HealthDay News. Side windows, however, blocked just 71% of rays on average. Some blocked as little as 44%. The gap in protection may be to blame for a greater occurrence of cataracts and skin cancers on US patients' left sides, Boxer Wachler says. "It had no correlation at all with the cost of the car," he adds. An expert at Louisiana State University says the difference might be that windshields are made of laminated glass to prevent shattering, while side windows are made of tempered glass, reports Reuters. "Don't assume because you are in an automobile and the window is closed that you're protected from UV light," she says. A dermatologist suggests wearing sunscreen and sunglasses while driving, and window tinting products are "a great option for those who have older cars or cars that don't have the protection already built in." (Time to count your moles.)