Aamir Mohd Khan/Pixabay

Certain colors are more dangerous than others.

Tattoos are more mainstream than ever: three out of ten people in the US have one. But the longterm effects of getting inked are still unknown.

A recent report from the European Chemicals Agency on the safety of tattoos and permanent make-up found that tattoo ink can increase the risk of cancer. The agency has called for more research, and is seeking to implement restrictions on tattooing in Europe.

Tattoo ink isn’t currently regulated in Europe. In the US, the Food and Drug Administration (FDA) regulates the chemicals in tattoo ink and cosmetic products, and recently began work on identifying exactly what’s in the color pigments used in tattoo ink. But due to a lack of research and other public health priorities, the FDA has not issued any strong regulations — or restrictions on ingredients — in tattoo ink or pigments.

Felix Brönnimann/Pixabay

According to the European Chemicals Agency, “Many reports show significant concerns for public health stemming from the composition of inks used for tattooing.” As their report explains, the “most severe concerns are allergies caused by the substances in the inks and possible carcinogenic, mutagenic or reproductively toxic effects.”

Yes, you read that correctly — the agency warns that tattoo ink could lead to cancer and affect reproductivity.

The European Chemicals Agency, which is Europe’s premier agency in charge of regulations that protect people from dangerous chemicals, suggests that red ink may be the most toxic, and found links between red inks containing containing mercury sulphide and dermatitis, which causes swelling and soreness in your skin. However, a 2006 study from the World Health Organization found that black ink was most often linked to potential adverse health effects like cancer or DNA damage.

The main concern is that tattoo ink pigment can travel from your skin into your body’s blood stream and potentially into your brain or lymph nodes. Dr. Samuel Epstein, who specializes in cancer prevention, claims that “the evidence which we’ve accumulated so far, is largely restricted to the fact that they [nanoparticles] get into your bloodstream and reach organs throughout your body. And as far as the brain is concerned, we have actual evidence of entry into the brain and producing toxic effects — lesions, small lesions, toxic effects in the brain.”

The inconsistency in studies on tattoo ink strongly suggests that more research needs to be done on the long term affects of tattoo ink. As the European Chemicals Agency says, even if it’s expensive to conduct, comprehensive research on ingredients in tattoo ink is urgently needed.