Is it dangerous?

No. The laser hair removal flash only consists in a very intense emission of red or infrared light very similar to that emitted by the grill of a kitchen stove. There are no radiations which could induce risks for the skin. The wavelength used for hair removal is completely different from that used for ultraviolet radiations or X-rays, which means there are no risks of mutation or cancer.

Mechanical and light stimuli can induce a degeneration of moles. It is thus important to avoid removing hair around and on them. Even laser experts can induce lesions such as burns, but these lesions remain much less severe than those induced by an iron, and disappear after a few weeks.