Mona Lisa's Smile Fading

All is not well in the city of light, Mona Lisa's smile is fading. Could it be it has to do with the literally thousands of people taking a picture of it with a flash every single day ? Could it be that with the technology of digital cameras being sold en masse in the past four-five years, people do not care anymore about wasting films and therefore increase the number of photos of the paintings, thereby increasing the amount of light the painting sees every day ? Could it be that flashes used for digital cameras are more powerful (mostly because they can - the camera recharger takes care of the flash nowadays and are often used by camera users to recharge the whole camera making it an essential item - ? In other words, does flash used nowadays with digital camera exceed 12 watts or is the Musee du Louvre gift shop at fault for selling to thousands of customers paper-cameras that have essentially no UV-filters built-in ?