With an estimated 30 percent of Americans now sporting at least one tattoo, going under the needle has never been so popular (1). But could the long-term effects of body art be more than skin deep? A study has shown that nanoparticles of tattoo pigments can travel from the skin to the lymph nodes, raising new questions about potential risks (2).

According to scientists from the German Federal Institute for Risk Assessment (BfR), safety concerns have been triggered by the increasing prevalence of tattoos. Earlier chemical analysis of tattooed skin has mostly been in vitro (3), but pigmented and enlarged lymph nodes have been noted previously in people with tattoos (4). The German researchers wanted to examine the phenomenon in more detail.