Health risks of tattoo colors

The number of tattooed individuals has increased significantly, especially among youth. In the United States ∼24% of the population is tattooed [1], whereas in Europe it is ∼10% [2]. Cosmetic tattoos (permanent make up) to mimic eye, lip or eyebrow-liner, have also become increasingly popular [3]. Tattoos or permanent make-up are simply performed by injection of colorants into the skin using solid needles. Injury of the skin and the application of unregulated colorants cause health problems in humans [4]. A survey is being performed by the Department of Dermatology of the University of Regensburg in order to elucidate the frequency of medical problems with tattoos [5], in particular after laser treatment [6].