There has been a lot of media attention focused on the UV light used to cure gel nails. Many studies have been done and there will be more to follow on it's potential to cause skin cancer. They are not completely safe from harm, just as fluorescent lights in offices or the sun. We are exposed to more UV rays by walking to our car than sitting under a nail UV lamp for a total of 10 minutes every few months. I think just as we should wear sunscreen all year round, and take care of our skin, we should be aware of any amount of damage and act accordingly. I don't think there is a need to panic, but I think it's important to be aware. Here is an article with more information...
Nail Pro Magazine