Disappearing Ink

Tattoo technology for modern impermanence

Watch a couple of episodes of the reality television show Miami Ink and you realize that tattooing has shed its outlaw image. People from all walks of life come into the show’s featured tattoo studio wanting to get designs etched into their skin.

Wearers of traditional tattoos can’t easily erase the marks of passions gone cold. New inks, consisting of pigments encapsulated in polymer microspheres, can be cleanly dispersed with a single laser treatment, so that tattoos are only as permanent as a person wants them to be. © Holger Scheibe/zefa/Corbis

IMPERMANENT INKS. Removable tattoo inks from the company Freedom-2 consist of nanosize pigment particles enclosed in plastic beads 1 micron in diameter. During removal, laser light breaks open the beads, allowing the body’s immune system to clear away the particles. Freedom-2

DISAPPEARING ACT. Martin Schmeig of the upstart tattoo-ink company Freedom-2 sports a tattoo made with microencapsulated inks (left). The design was subsequently removed by a single laser treatment that left only a hint of the original just weeks later (right). Freedom-2

Many women are taking the plunge, and tattooing has almost become a rite of passage for young people. According to a Pew Research Center survey released in January 2007, 36 percent of 18- to 25-year-olds and 40 percent of 26- to 40-year-olds have at least one tattoo. By contrast, only 10 percent of people age 41 to 60 do. And women are nearly even with the men: 16 percent of men and 15 percent of women report having one or more.

Not everyone ends up happy with his or her tattoo, however. A 2003 Harris Poll found that 17 percent came to regret the decision. The most frequently given reasons were that the tattoo included the name of a once-but-no-longer-cherished person, just didn’t look attractive to its owner anymore, had faded over time, or “was stupid.”

Enough people want to correct their mistakes that tattoo removal is a growing business. Around Los Angeles, for example, centers with names like Dr. Tattoff, Tat2BeGone, and Tattoo MD have sprung up. Tattoo removal is an expensive, painful, and less-than-perfect process that involves using laser light to break up the pigments so that the body’s immune system can clear them away. Multiple treatments are necessary, and they can leave scars and change the color of the skin. Still, thousands of people each year are willing to go through it.

Now, a company called Freedom-2 in Camden, N.J., is hoping to make removing a tattoo almost as easy as getting one. The company has developed an ink that can be removed with just one laser treatment that leaves no scarring. It plans to introduce its first inks commercially this fall.

But success may depend on whether artists accept the new ink. Does a removable ink contradict the idea of what a tattoo is? Or will it change the notion of what is permanent?

Ancient art

The art of tattooing has existed for centuries and in many cultures. The earliest pigments were often natural compounds such as charcoal and plant extracts. Nowadays, inks are made industrially, and established artists usually purchase them from reputable suppliers that ensure that the products are safe. “I’ve been using the same supplier for the last 30 years,” says Sailor Bill Johnson, a tattoo artist in Orlando, Fla., and vice president of the National Tattoo Association. “It’s just what we’ve had success with and what we know is good.”

Tattoo inks are classed as cosmetics and in principle need approval by the Food and Drug Administration before they can be sold. But because there haven’t been any widespread concerns about tattoo safety, the FDA historically hasn’t made an effort to regulate inks and pigments. The actual practice of tattooing falls under state and local regulations.

On its Web site, the FDA’s Center for Food Safety and Applied Nutrition warns that some color additives in tattoo inks are approved for use in cosmetics, but “none is approved for injection under the skin…. Many pigments used in tattoo inks are not approved for skin contact at all.” The FDA does track adverse effects from inks and says it will take action if necessary, but so far, other public health issues have taken priority.

The suppliers themselves are close-lipped about their formulas. A spokesman for National Tattoo Supply in Allentown, Pa., one of the most trusted suppliers of inks, said the company “wouldn’t dream of revealing what’s in our ink.”

Chemists Jani Ingram of Northern Arizona University in Flagstaff and Ronald Petruso of Delaware Valley College in Doylestown, Pa., and their students have done studies to characterize some of the ingredients of 17 inks from five manufacturers. They found that some contained heavy metals, such as lead, while others had carcinogenic compounds. The group traced one such compound to Sun Chemical in Cincinnati. The company created the pigment for use in automobile paint and didn’t know it had been added to tattoo ink, Petruso says.

Still, the primary health risk associated with getting a tattoo comes not from the composition of the ink but from infection. Improperly sterilized equipment can transmit hepatitis, HIV, or bacteria such as Staphylococcus aureus. Allergic reactions to the ink can occur but are rare, according to the FDA.

“In a holistic sense, tattooing is very safe,” says Martin Schmeig, president of Freedom-2, the maker of the new removable ink. “The art of tattooing has been around for 12,000 years.”

Modern tattoo artists use an electrically powered machine—sometimes referred to as a “gun”—to place designs into the skin. The machine punctures the skin hundreds of times per minute with a solid needle, creating a series of holes in the skin at a depth of about a millimeter. Ink from a reservoir flows down the needle and fills up the holes. “Tattoo inks are not injected into the skin; they’re forced into the skin,” Schmeig explains. “The needle is literally creating a hole and ramming the pigments into the dermis.”

The depth of the delivery of those pigments is critical, Schmeig adds. When the ink is deposited, immune cells called macrophages ingest the pigment particles and hold them permanently in the dermis. “They’re like pit bulls; they grab on and won’t let go,” Schmeig says. Each pigment particle is encased by a single macrophage, which protects it from degradation by enzymes and from ultraviolet radiation that can cause the tattoo to fade.

For the tattoo to form properly and endure, the pigment particles have to be the right size. They must be small enough for macrophages to envelop but not so small that they get digested and cleared away by the cells. The scientists involved in Freedom-2 have found that the optimal size is around 1 micrometer, Schmeig says. The macrophages wall off the pigment particles in an attempt to neutralize any threat they might pose. The cells sit there, permanently holding the pigment in the skin.

Second thoughts

To remove a traditional tattoo, a dermatologist shines a laser on the design, and the laser’s energy breaks the pigment particles into nanosize bits. The immune system then clears away and disposes of the particles as it would bacteria or viruses. “But a laser does two things,” Schmeig explains. “Not only does it cut up the particle, but it actually damages the dermis, and you get an inflammatory response.”

Removing a tattoo usually requires multiple treatments, since each pass with the laser might destroy only a portion of the pigments, and the skin needs time to heal before the next round. Also, lasers of several different wavelengths might be needed—one for each color in the tattoo.

The removal process isn’t perfect either. It can result in scarring or changes in the natural pigmentation of the skin, leaving a silhouette of the original tattoo, says Bruce Klitzman, senior director of Duke University’s Kenan Plastic Surgery Research Center. The idea for a removable ink originated from one of Klitzman’s surgical residents, Kim Koger, who noted that mastectomy patients often get a tattoo to simulate the areolar area around a nipple reconstructed from tissue. But as the breast heals, the nipple can shift position, and the patient ends up unhappy about the result. “It would be best to start with an ink that’s more susceptible to erasing—to use a pencil instead of a pen,” Klitzman realized. That way, the tattoo could be removed and redone, if necessary.

Tattoos have other medical applications, too. People who have difficulty applying makeup—a woman with Parkinson’s disease, for example—might get eyeliner or lip liner tattooed on. Cancer patients receiving radiation therapy often have targets tattooed on and would like to get that reminder of their illness removed after their treatments end.

Klitzman and Koger filed a patent on their concept—the first ever for a tattoo ink. It was a broad patent describing an ink that would consist of a pigment encapsulated in a polymer. Exposing the microcapsule to energy of some sort—the patent listed a range of possibilities—would release the ink.

Around that time, another group, headed by dermatologist R. Rox Anderson of Harvard Medical School in Boston, had the same idea. Anderson, who also directs the Wellman Center for Photomedicine at Massachusetts General Hospital, had treated many patients who wanted their tattoos removed and had been working on making nontoxic pigments. But these pigments faded quickly, so he came up with the idea of enclosing them in a polymer to make them last longer. “Literally within days of one another, both of these independent groups patented almost exactly similar ideas,” Schmeig says.

Anderson’s group filed a patent-interference action, and the two parties spent a year in front of a patent judge, Klitzman says. The judge encouraged the two parties to negotiate, and a venture capitalist named Craig Drill put up the funds for the groups to form a single company, Freedom-2.

Freedom-2 inks consist of nanosize pigment particles encased in polymer beads 1 micrometer in diameter—the ideal size for macrophages to ingest and hold in the dermis. The researchers chose pigments and polymers that the FDA generally recognizes as safe, such as food colorings and materials used in medical implants.

The polymer beads also contain a dopant that absorbs light of a particular wavelength. When it comes time to remove the tattoo, the dopant “enables you to burst the bead with a single wavelength, independent of what color is in the bead,” Schmeig explains. “That dopant could be a piece of iron oxide, a fleck of gold—anything that can absorb a wavelength and create enough energy to explode this polymer bead.”

The released pigment particles are of a size that the body can clear away. Instead of using a laser to break apart the large pigment particles, the researchers use the high-intensity light just to crack open the polymer shells.

To demonstrate the technology, Schmeig got a Freedom-2 ink tattoo on his left arm in August 2006 and then had it removed in December. A couple of weeks after the treatment, his arm had just a few faint traces of the ink. “If I wasn’t the [chief executive officer] of this company, I probably wouldn’t have ever imagined getting a tattoo,” Schmeig says. Now, he sports another one on his right arm in the company’s new black ink, which this fall should become the first of the company’s inks to go on the market. The three primary colors—red, yellow, and blue—will come next.

Klitzman believes that this work is an opportunity not just to make tattoos removable but to push the science of tattooing forward. The medical applications of tattooing have brought the practice into the scientific community, he says, so researchers can apply scientific methods to make better inks with better properties.

Artistic differences

Clients will know that a tattoo artist offers Freedom-2 ink by the neon sign in the studio window—much like the glowing beer signs that decorate many bars. Though some artists have embraced the idea of a removable ink, others are skeptical. Sailor Bill Johnson says he would be reluctant to try out a new type of ink, since the ones he has been using for decades work well. “If it’s not broken, you don’t fix it,” he says. What’s more, if a client came into his studio asking for a tattoo that might be removed later, he would counsel the person not to get it in the first place.

That philosophical difference is something “we honor and respect,” Schmeig says. “On the other side of that, the tattoo artist isn’t the wearer of the tattoo. The fact is that life circumstances change. What you do when you’re 25 may not be what you want as a remembrance when you’re 45, 55, or 65.” Schmeig sees the ink as something permanent but that preserves the option of later removal.

“We are not in the business of creating temporary tattoos,” he says. “We urge everyone who is thinking about tattoos to think of them as a permanent decision.”

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