Mind & Body

Do You Know What Chemicals Are in Your Tattoo?

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Human beings have been tattooing themselves for thousands of years. Prehistoric cavemen and Egyptian royals brandished tattoos made from soot, charcoal, and other natural pigments. But modern tattoo artists often have little knowledge of what their inks are really made of. Do you know what's in your tattoo?

Unknown Inks

Although tattoo artists must be certified in order to work legally, tattoo inks and pigments are not regulated by any government authority. Unless you're a professional tattoo artist and you mix your own inks from dry pigments, there's a good chance you'll never find out exactly what goes into tattoo ink.

This may partly be a result of ink manufacturers protecting their proprietary formulas. Regardless, tattoo artists and enthusiasts usually have no idea exactly what chemicals are in their tattoos — and it turns out that the range is huge. Some pigments are sourced from natural ingredients, while others can be sourced from the textile, plastic, or automotive industry.

A 2016 report from the Joint Research Centre (JRC), which provides independent scientific advice to the European Union, chemically analyzed a wide variety of tattoo pigments and listed the ingredients of most concern. The most dangerous are known as polycyclic aromatic hydrocarbons (PAHs), a chemical group found in mostly black inks that contains carcinogens that can migrate from the skin to the lymph nodes. There are also azo pigments, which make up about 60 percent of the color ingredients in tattoo inks. Though azo pigments are safe when they first enter the skin, they can degrade over time into potentially cancer-causing compounds.

A Swiss survey of 229 tattoo inks also found problematic preservatives. A quarter of the inks that survey analyzed contained the skin irritant benzo-isothiazolinone and 7 percent contained formaldehyde, a carcinogen. Tattoo inks can also contain harmful metals such as nickel, chromium, and cobalt.

Related Video: Tattoo, the Permanent Art

How to Protect Yourself

That doesn't mean all tattoos are unsafe. Modern high-quality pigments are typically made from various metal salts. Different metals pose different risks, which means certain colors are inherently riskier than others. Red ink, in particular, is known to cause sensitivity reactions and other health problems more often than black ink, which can be easily manufactured from safe sources. Blues and greens made from high-quality copper salts tend to be safe as well but watch out for cobalt-based blues. White pigments made from titanium oxide are some of the least reactive pigments in the industry. While yellow pigments are often derived from natural sources like turmeric or curcumin, they commonly cause reactions because of how much pigment it takes to create a bright color.

If you want to be safe about getting a tattoo, stick to reputable artists and don't be afraid to save up and pay a premium price. Cheap inks are cheap for a reason, and unscrupulous tattoo artists won't be able to offer evidence supporting their ink choices. You should ask your tattoo artist to provide as much information as possible about where the inks came from and what they're made of, and be specific about the colors involved. A tattoo is forever, after all.

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Humans have been decorating their skin for as long as humans have been around. Dive into that artistic history in "The Tattoo History Source Book" by Steve Gilbert. We handpick reading recommendations we think you may like. If you choose to make a purchase, Curiosity will get a share of the sale.

Written by Austin Jesse Mitchell March 6, 2019

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