Researchers from Germany and France have determined that particles from tattoo ink can travel inside the body and reach the lymph nodes. The study, published in Scientific Reports, provides the first evidence that various pigments and toxic element impurities are transported through tattooed tissues.
Scientists at the European Synchrotron Radiation Facility (ESRF) also discovered in-depth characterization of the pigments in the tissues. Hiram Castillo is a scientist at the ESRF and one of the authors of the study.
“When someone wants to get a tattoo, they are often very careful in choosing a parlor where they use sterile needles that haven’t been used previously,” explained Castillo. “No one checks the chemical composition of the colors, but our study shows that maybe they should.”
Little is known about the potential impurities in the color mixture applied to the skin. Most tattoo inks contain organic pigments, but also contain contaminants like nickel, chromium, manganese, or cobalt.
Other than carbon black, the most common ingredient used in tattoo inks is titanium dioxide (TiO2). This white pigment, also commonly used in food additives and paints, is used to create specific shades when mixed with colors. TiO2 tattoos often cause delayed healing, skin elevation, and itching.
Until now, potential health hazards from tattoos had only been investigated by chemical analysis of the inks. Two particular beamlines used in the current study allowed a team of scientists to clearly view titanium dioxide located inside of the tissue.
Overall, the scientists found strong evidence for both migration and long-term deposition of toxic elements and tattoo pigments in the skin and the lymphatic environment. A broad range of particles – up to several micrometers in size – were located in human skin, but only nanoparticles had traveled to the lymph nodes. The scientists warn that these particles could lead to chronic enlargement of the lymph node and lifelong exposure.
Study co-author Bernhard Hesse is a visiting scientist at the ESRF. He explained, “We already knew that pigments from tattoos would travel to the lymph nodes because of visual evidence: the lymph nodes become tinted with the color of the tattoo. It is the response of the body to clean the site of entrance of the tattoo. What we didn’t know is that they do it in a nano form, which implies that they may not have the same behavior as the particles at a micro level. And that is the problem: we don’t know how nanoparticles react.”