On October 12, 2017, the German Federal Institute for Risk Assessment (BfR) published questions and answers (Q&A) regarding a study on whether nanometric pigments from tattoo inks can permanently accumulate in lymph nodes.  BfR states that by using X-rays from a particle accelerator in Grenoble, it discovered where the pigments accumulate in the tissue.  According to BfR, until now, the accumulation of pigments from tattooed persons has been known by optical coloring of the lymph nodes only, as they often had been of the same color as the tattoo.  Both skin and lymph nodes have now been characterized in terms of their chemical composition, pigment identity, and size.  The study, “Synchrotron-based ν-XRF mapping and μ-FTIR microscopy enable to look into the fate and effects of tattoo pigments in human skin,” was published in September 2017.