It may not be the fault of the tattoo ink, when some people are allergic to their tattoos, but to metallic particles from needles that bring color under the skin. This surprising assumption is made by a team led by Ines Schreiver of the Federal Bureau of Risk Assessment (BfR) and Bernhard Hesse of the European Synchronization Institute in Grenoble based on new data on what is happening in a body with small metal fragments. Surprisingly large quantities of these particles, the size of just a few micrometers or even nanometers, are released from the needle during the tattooing process, the group reported in a publication in Toxicology of Particles and Fibers. The problem is that the needles are made of stainless steel and contain chromium and nickel – two elements that cause sensitivity and allergic reactions in many people. Metallic particles migrate to the lymph nodes after surgery, probably causing an immune reaction. The study makes no statements about the direct association between metal particles and allergies.
The team examined skin and lymph nodes samples from a total of six tattooed individuals, one of whom had a known contact allergy. Using X-ray fluorescence analysis, which excites X-ray elements in the sample and identifies them by the light they emit, the group found nickel and chromium-rich iron particles in all the samples. To determine their origin, Schreiver and Hesse then tested on pig skin how much such stainless steel abrasion actually remains when tattooed on the skin – and in these experiments showed a surprising accomplice. If the paint contained actually harmless white pigment titanium dioxide, many more such particles were produced than in the experiments with titanium black ink. The task force suspects that very hard oxide particles act like sandpaper and significantly increase abrasion. Despite this finding, toxic components in ink remain a bigger problem at the current stage, Schreiver told Time Online.