A new review published in The Lancet stated that short-term risks are talked about with regard to tattoo, but not much is known about long-term risks of living with ink under skin. Experts said there is no evidence stating that inks used for tattoo are safe.

Study author Dr. Andreas Luch of the German Federal Institute for Risk Assessment in Berlin was of the view that between 1and 5% of people who have get tattoo done suffer from a bacterial infection. Some people can also suffer from allergic reactions to the ink.

Luch said that these are short-term effects. It gets difficult to judge long-term effects as in many nations, tattoo inks are classified as cosmetics. As the inks are classified as cosmetics, its long-term effect cannot be testing on animals. Luch thinks that tattoo ink should be considered as different product category.

Luch said that they agree that the skin barrier keeps surface cosmetics out of the body. But he also stated that tattoo ink is injected into live tissues that comprise of blood vessels, nerves and immune cells.

“We need to assume that all of these ink ingredients, including preservatives, processing aids or whatever, will become systemically available in the body over time. Regulation based on cosmetics is insufficient”, said Luch.

Upon assessing the bodies of dead people who had tattoos for decades has shown that around 90% of the ink has disappeared from the skin. The acute risks are still unknown.