Emily Pratt wasn’t impressed when she heard about the U.S. Food and Drug Administration probe into the potentially deleterious effects of tattoo ink. She would have shrugged to show how little she cared, but she was a bit sore from the tattoo machine that had just been smacking away at her left forearm.

This was her seventh inking, after all: a wrap-around bouquet of six roses in shades of yellow and red rendered at Embassy Tattoos in Washington. “The fact that I’m here,” the 22-year-old said, recovering in the waiting room near a stuffed mongoose, “says I’m not worried about the side effects.”

But the FDA is, as are some experts in the field. The concern has grown with the explosion in the body art’s popularity and the availability of tools and inks online. The industry is growing about 9 percent a year, a rate research company IBISWorld projects will make it a $1.1 billion business by 2020.

“Even the most reputable places can’t guarantee the safety of ink,” said Arisa Ortiz, a dermatologist and assistant professor at the University of California, San Diego, and co-author of a 2011 article that cited reports by researchers in Spain, Germany and the U.S. who discovered substances including mercury and charcoal in tattoo dyes.

Industrial-Grade Colors

In the U.S., the inks are regulated as cosmetic products. The FDA can screen them before they hit the market but has rarely done so, according to its website, because of “competing public-health priorities and a previous lack of evidence of safety problems specifically associated with these pigments.”

The agency does investigate when it receives complaints, and these have been on the rise: Hundreds have been filed since 2004 compared with just five between 1988 to 2003, reporting reactions including itching or scarring or inflamed skin even years after tattooing occurred.

One issue could be the proliferation of do-it-yourself equipment and inexpensive dyes, said “Sailor” Bill Johnson, vice president of the National Tattoo Association. “I’ve been using the same product for nearly 40 years and have never had a problem with it.”

Scientists at the FDA’s National Center for Toxicological Research in Jefferson, Arkansas, are exploring several aspects of ink’s impact once it’s been under the skin for a while, including how the chemicals metabolize in the body.

One-In-Four

“Many pigments used in tattoo inks are industrial-grade colors suitable for printers’ ink or automobile paint,” the agency says on its website. Chemists have discovered some yellows break down when exposed to sunlight or certain enzymes, though it hasn’t been determined whether this is toxic. The FDA hasn’t said when its ink study will be done.

By some estimates, about 30 percent of the U.S. population and one in four millennials sports at least one tattoo, though, according to the Pew Research Center, the majority have theirs in places that can be hidden from view.

“Tattooing has become mainstream,” said Diane Pacom, a University of Ottawa sociologist. “The millennials, they’re doing it as a statement of belonging to the system – because everybody has tattoos now.”

Including many filled with regret. Tattoo removal is also a growing business, with IBISWorld predicting it will be an $80-million-a-year industry in 2018, up from $40 million in 2008.

Gen Z

Would negative findings by the FDA greatly dim tattooing’s allure? Lars Krutak, a tattoo-history expert at the Smithsonian Institution’s National Museum of Natural History, doesn’t believe so. After all, millions still smoke despite the risks. But what the FDA discovers, he said, may lead to “better regulation, quality standards, labeling and even the reclassification of tattooing ink itself.”

The tastes of Generation Z may determine whether the U.S. has reached peak tattoo. Coming along behind the millennials, this cohort includes kids born from the mid-90s to the mid-2000s. According to researchers, Gen Z is more cautious and more driven to be successful after seeing older siblings struggle to find work and live with their parents in record numbers.

Anna Felicity Friedman, a tattoo historian who estimates 50 percent of her body is covered in ink, said no matter what the FDA concludes, the U.S. “may be at a tipping point in tattoo popularity.” Young people she knows “are consciously deciding to remain untattooed, either to be rebellious, since tattoos are no longer a mark of rebellion, or to avoid being deemed a fashion victim.”

Jason Recker, a 15-year-old from Peoria, Illinois, has already done some research. “You don’t see a lot of tattoos on lawyers and engineers and teachers,” he said, considering future careers. “I don’t think I’ll want to get a tattoo when I’m old enough.”