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Consumer Safety

What chemicals are in your tattoo?

European regulators worry about the inks used to make body decorations, which can be repurposed from the car paint, plastics, and textile dye industries

by Sarah Everts
August 15, 2016 | APPEARED IN VOLUME 94, ISSUE 33

Credit: Shutterstock
According to current surveys in Italy, Denmark, and the U.S., more women than men have tattoos.

Humans have been tattooing themselves for millennia, motivated by reasons as diverse as the designs decorating their skin. Crusaders tattooed crosses on their bodies to ensure they’d go to heaven, while for centuries, sailors inked their bodies to boast about where they’d travelled. The 61 tattoos on Ötzi, a 5,300-year-old mummy discovered in the Alps, were all located near his joints, leaving researchers to speculate that the tattoos may have been part of an ancient arthritis treatment.

These days, however, most of the 120 million tattooed people worldwide have inked themselves for fashion. This trend is on the upswing among young adults, especially women, who now possess more inked body art than men in Italy, Denmark, and the U.S., according to Darren McGarry, who led a panel discussion about tattoo science and policy at the European Science Open Forum (ESOF) conference in Manchester, Eng­land, in late July.

But if tattoos are now commonplace, knowing the ingredients and provenance of the colorful cocktail injected beneath the skin is not. It’s not widely known by the general public that the pigments found in tattoo inks can be repurposed from the textile, plastics, or car paint industry, said McGarry, who works at Joint Research Centre (JRC), which provides independent scientific advice to the European Commission.

Members of the ESOF panel voiced concern about patchy regulatory oversight of tattoo inks in the European Union and about a tattooing culture in which consumers rarely question tattoo artists about the origin of the pigments that decorate their bodies. Given these issues, they called for research on the long-term health risks of tattooing and for harmonizing regulations controlling tattoo parlors and inks across the EU.

Credit: Joint Research Centre
Tattooed inhabitants in these countries and regions compose less than one-quarter of the population.
Source: Joint Research Centre
Credit: Joint Research Centre
Tattooed inhabitants in these countries and regions compose less than one-quarter of the population.
Source: Joint Research Centre

According to a report the JRC released this year, European regulators and others are concerned that “pigments used in the formulation of tattoo and permanent make-up inks are not produced for such purpose and do not undergo any risk assessment that takes into account their injection into the human body for long-term permanence.”

The report notes that in the U.S. and Canada, policies that govern tattooing are also spotty. In those countries, the procedure is regulated at state or provincial levels, generating “a wide variety of guidelines and hygiene standards.”

Tattoo artists also have concerns. “There are certainly really good producers of ink. But some of the inks on the market weren’t intended for tattooing. They just put them in a fancy bottle, put a dragon on the bottle, and write ‘tattoo’ on it,” said Jens Bergström, who has been a tattoo artist for 20 years and owns the Heavenly Ink Tattoo & Piercing studio in Åkersberga, Sweden. “That’s how easy it is, and that’s the danger,” said Bergström, who was a panelist at ESOF.

The 118-page JRC report—which compiled surveillance, ingredient analysis, and adverse reaction data—found that tattoo and permanent makeup products containing dangerous substances or contaminated by microbes “are available on the EU market. The main risks identified, in descending order, are the presence of polycyclic aromatic hydrocarbons, primary aromatic amines, microorganisms, heavy metals, and preservatives.”

“Most consumers are aware of the infection risks, but few are aware of the chemical risks,” said Anke Meisner, a policy officer at the German Federal Ministry of Food & Agriculture and a panel member at the ESOF conference. According to the JRC report, from 2005 to 2015, chemical ingredients were the primary concern in 95% of the 126 tattoo ink cases reported to the EU’s rapid alert system for dangerous products.

Inks imported from the U.S. were responsible for two-thirds of the tattoo-related alerts sent to European authorities, the JRC report says. A further one-quarter of these problematic inks came from China, Japan, and some European countries, while the provenance of 9% of products was unknown.

According to the JRC report, the bulk of tattoo health complications involve allergic reactions and hypersensitivity, mostly in red or black areas of tattoos.

Some azo pigments found in tattoos, such as Solvent Red 1, can degrade into problematic compounds such as o-anisidine, a potential carcinogen.

Dermatologist Jørgen Vedelskov Serup of Bispebjerg Hospital says he’s cared for 500-plus problem tattoo cases. Serup told ESOF attendees he’s seen lumpy, so-called papulonodular skin elevation from pigment overload, chronic inflammation, long-term light sensitivity and other side effects from tattooing. “As a doctor, if you do a cosmetic procedure, by law, you have to tell the patients the risks. It’s amazing that the same is not [universally] required in tattooing,” Serup said.

Tattoo inks can contain a cornucopia of compounds: Some 100 pigments and 100 additives have been found in these products, Maria Pilar Aguar Fernandez told ESOF attendees. She is responsible for the Chemicals Assessment & Testing Unit at the JRC and was involved in writing the organization’s tattoo report.

The top chemicals of concern found in tattoo inks, according to the report, are polycyclic aromatic hydrocarbons (PAHs), such as benzo[a]pyrene, which is listed as a human carcinogen by the International Agency for Research on Cancer (IARC). The report notes PAHs can migrate from the skin to lymph nodes. These problematic chemicals are found mostly in black inks and are most likely impurities from industrial production—in fact, some tattoo formulations are only between 70–90% pure, the report says. Tattoo inks may also contain potentially harmful metal impurities such as chromium, nickel, copper, and cobalt.

Tattoo pigments themselves can be health hazards. “If the ink is really bright in color, it usually contains dangerous stuff,” tattoo artist Bergström said. Fortunately, cinnabar, a mercury sulfide pigment, which was once a popular bright red in tattoo formulations, has been phased out of use.

Currently, stakeholders are more concerned about azo pigments, the organic pigments making up about 60% of the colorants in tattoo inks. Although many of these azo pigments are not of health concern while chemically intact, they can degrade with the help of bacteria or ultraviolet light into potentially cancer-causing primary aromatic amines, notes the report.

Furthermore, during tattoo removal—by some surveys up to 50% of tattoo owners come to regret their ink—lasers are often used to blast apart pigments, sending problematic degradation products into the body.

Researchers don’t know “how these degradation products are distributed in the body and how they get excreted,” Meisner said. “There’s a knowledge gap about metabolism of ingredients.”

Another problematic component of tattoo inks is the preservatives that can be added to keep microbes from growing in the often nutrient-rich solutions. In one survey of 229 tattoo inks by Swiss regulators, nearly a quarter of inks analyzed contained the antiseptic benzo­isothiazolinone, which is a skin irritant. Also, 7% of inks in the study contained the preservative formaldehyde, which is classified as a carcinogen by the IARC.

The JRC report highlights the need to fund research on the toxicity of tattoo ingredients and how they degrade in the body as well as to fund the development of analytical techniques to detect and monitor impurities. “Prospective epidemiological studies would be needed to ascertain the risk of carcinogenicity from tattoo inks constituents, including their degradation products,” says the report, which also lists this as a research priority.

“We are facing a tremendous knowledge gap. This is why it is so difficult to develop regulations,” dermatologist Serup said.

Across the EU, tattoo inks are regulated under a blanket consumer product law that dictates only safe products may be placed on the market. The European Chemicals Agency is currently investigating whether tattoo ink ingredients should be subject to region-wide regulatory restrictions.

In 2008, the Council of Europe, an organization focused on promoting human rights and the integration of regulatory functions in the continent, recommended policies to ensure the safety of tattoos and permanent makeup. This document lists 62 chemicals that should not be present in tattoos and permanent makeup products. It also recommends that tattoo ink bottles should list best-before dates, batch numbers, and “the name and address of the manufacturer or the person responsible for placing the product on the market,” among other things.

Motivated by the Council of Europe’s recommendations, about one-third of EU countries, including Germany, Spain, and France, implemented a mishmash of their suggestions through national laws. For example, among other regulations, Germany has made it illegal for tattoo inks in the country to contain any chemicals on the Council of Europe’s list of substances banned in cosmetics. “What is not safe on the skin is not safe in the skin,” Germany’s Meisner said. Other EU countries have instituted licensing requirements for tattoo artists or made it illegal to tattoo without informing clients of potential health risks.

Meanwhile the JRC report points out that no information about tattoo regulations was available for Hungary, Iceland, Lithuania, and the U.K. “We have not done any market surveillance in the U.K.,” said Robert Pinchen, a U.K. market surveillance representative at the ESOF conference. “I’m very concerned about the amount of potential counterfeit inks that are on the marketplace and all these do-it-yourself kits that are available,” Pinchen added.

It’s frustrating that different countries have different rules, said Bergström, the tattoo artist. “We want harmonized rules in the whole European Union.” Until that happens, Bergström suggests that individuals getting a tattoo make informed decisions.

“Nobody gets forced to have a tattoo. So it’s in your own interest as a consumer to ask questions. If the tattoo artist can answer your questions and produce some documents regarding the ink, that’s a good thing,” Bergström said. “As a practitioner, it is my responsibility that I produce as [low a] risk as possible.”

But, he added, “Don’t just take for granted that all tattoo artists are good or all inks are good. You are also responsible for your own health.” 

ACS's Reactions team explains what goes into tattoo inks and what makes tattoos permanent.
Credit: ACS Reactions


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Thomas (August 10, 2016 2:15 PM)
No mention of ABS (acrylonitrile butadiene styrene)plastic apparently common as a main ingredient in tattoo pigments.
Thomas (August 10, 2016 2:17 PM)
oops - my mistake (not ABS specifically but..)
Richard (August 10, 2016 2:22 PM)
Can the ink in the skin be removed and if so how?
Lisa (August 10, 2016 2:36 PM)
As a former tattooist, and now student of chemistry, what this article discusses is one of the reasons why I went back to school. The lack of regulation in tattoo ink is shocking. Many manufacturers decline to reveal all the ingredients of their inks claiming it a trade secret. There is also a knowledge gap amoung some tattooists regarding any of the ingredients of their ink. Here in NYC there is a story about how a group of tattooers in the 1970's ordered pigment directly from a chemical company, they received such a large quantity that it is still being used today. Needless to say they did not differentiate between automotive or cosmetic pigments due to ignorance. In modernity tattooing has largely existed as an outside art form, illegal in many places until recently. With its growth in popularity the rest of the world is paying attention to the practice of tattooing. Lets work to make it as safe as possible so that people will have the freedom to adorn themselves as they wish.
Joseph DiVerdi (August 10, 2016 4:24 PM)
Thank you for an interesting, topical and informative article.

I am, however, writing to pick at one particular point: the subtitle indicates concerns over repurposing inks from other industries. While the concerns certainly exist I would like to suggest that they (1) do not represent best chemistry thought, (2) should not be reproduced directly in best chemistry literature and (3) ought to be vigorously corrected whenever possible by chemists.

I submit that the industry of first or earlier use of a particular chemical is not central when introducing it into a subsequent or latter industry. It is the usability and topical safety in the new application that is important and even crucial. It makes big headlines to report that a substance has been used in some circumstance where it appears "dirty" or "unpleasant" in some way.

It is conceivable that some carbon atoms present in a most nutritive and wholesome food product for humans today may have cycled through some other highly toxic defensive molecule created and owned by an earlier squid, mold, jellyfish and so on after being synthesized in the violent explosion of a supernova (shudder).

We need to inform the public that chemicals do not, contrary to popular opinion, do not have, give or get the "cooties."

It is instructive to note that this very practice has been popular in the anti-fluoride in drinking water movement as an argument against this effective public health policy. Google, for example, "fluoride in water from other industries."

I encourage scientists and science writers to strive to guard against logical flaws and fallacies to the best of their ability and help all members of our society understand the best of our human knowledge.
R J Del Vecchio (August 14, 2016 1:42 PM)
Thank you, Mr. DiVerdi,for this nice reminder that we are all supposed to be scientists, working strictly with facts, data, and cogent, detailed statistics whenever possible. The insertion of emotional terms into articles about science has become somehow acceptable in recent years, also the subtle application of some biases, and none of this is proper or worthy of those who are supposed to be working consciously to present only objective articles. I have been increasingly concerned with the drift of some parts of ACS publications into less than rigorous science.
J. A. Beck (August 10, 2016 4:44 PM)
As someone who is extensively tattooed (1972 to present), I've tried to do at least some research on the safety of the inks and the hygiene of the tattoo parlor. It took me 10 years to feel comfortable with the new fluorescent inks. I've never had a problem and I wouldn't change any of my "decorating" decisions. Tattoos are like potato chips. You can't have just one.
grant mckenzie dewar (August 10, 2016 9:16 PM)
be ideal if components of inks would be actuALLY THERAPUETIC naturally sourced....allergy tested per individual before application

Jon Cleland Host (August 11, 2016 9:47 AM)
Several claims here do not appear to be supported. First of all, the article contains a statement about "dangerous stuff" (is that a scientific term?), by what expert? "A tattoo artist". Next, baseline context numbers were often left out. For instance, citing "500" tattoo problem cases would be more meaningful if compared to the number of tattoos applied in his area - thousands? Millions? hundreds of millions? How does this compare to, say, hair removal treatments, or other procedures? Another case of uncritical writing- "some surveys put tattoo regrets at 50%"? What surveys? How controlled were they? Even a poor quality internet survey at yougov put it only at 25%, and estimates based on reliable numbers puts it lower, at 0.1% of people with tattoos getting one removed in 2013 - even adding that across years isn't enough to get to "50%". For a magazine read by many people able to think critically, compare numbers, and rely on supported arguments, this article leaves a lot to be desired - regardless of whether one likes tattoos or not.
Michael (August 11, 2016 2:07 PM)
Generally, tattoos are removed by laser treatment. This removal is imperfect. Several types of lasers are used: Nd/YAG at 532nm and 1064nm, Ruby at 690 nm and Alexandrite at 790nm. Black tattoos composed of carbon black are the most common tattoos and can be removed at virtually all of these wavelengths since carbon black is a very broad absorber. These lasers pulse about 1 joule in nanoseconds or picoseconds. Spot size is varied from about 2mm to 7mm and fluences are anywhere from 2-10 joules/cm2. The tattoo pigment must absorb enough of the energy to jump hundreds of degrees C in temperature. This fractures the pigments into smaller particles which are removed by the bodies immune system. It often takes many of these treatments to remove a tattoo and the removal often leaves some kind of image behind. These treatments can be quite painful. It is also common, instead of removal, to cover up the undesired tattoo with a new tattoo which covers/incorporates the old tattoo.
Anna Fuskas (August 12, 2016 4:09 AM)
Do you know if Li tatoo inks contains formaldehyde or formaldehyde resins? They call themselves "pure and organic " so I am wondering what that means?
Maria Rose (August 13, 2016 5:20 PM)
I got my first set of tattoos after I turned 50. I had a bad scar on my left arm on the area from my elbow to shoulder. I checked into cost and pain of both laser removal and covering it with a tattoo design. In doing my research I talked with the 2 oldest tattoo places in my area (both had been doing this for over 30 years). Both had at least one person who specialized in covering scars. As my burn scar was raised at time I was told by both the tattoo places and the place that could do laser surgery, I had to wait anew years for scars to get flat against skin and I was told to use the special cream for reducing scars. So I waited 2 years and continued to research. I found out that laser surgery would not remove all appearance of scar so it would like I had an injury there permanently and would be a more painful procedure (at that time 10 years old).I decided to go with a tattoo to cover the scar area and worked with a tattoo artist who could take my drawing of design and fashion it nicer.I di use some colors but just enough to make it look like like a picture. I din't use any colors that would fade over the years.. All I do to freshen the tattoo is to apply the same cream I use for my face.
Doug Schoon (August 20, 2016 1:21 PM)
Lots of silly statements in this article. For instance, formaldehyde is a gas, and only a carcinogen when inhaled at high concentrations for long periods. The article was probably referring to formaldehyde releasing preservatives. They release trace amounts and this use is not a cancer risk, since only brief, trace exposures can occur. I expect more from a science-based magazine. I won't bother pointing out the other sloppy statements made. Both you writer and editor should focus on facts.
Leanne (August 22, 2016 4:54 PM)
Formaldehyde is soluble in water (as the hydrate), you can purchase it as a 37% aqueous solution. It's a very common tissue fixative agent, and could be added to inks for its microbial properties. Those solutions tend to be quite corrosive so I definitely would not want any injected into me!
So while I agree that this piece did not have the greatest rigour, the potential of having formaldehyde in unregulated beauty products is a concern. The body modification really needs regulation, even some more respectable practitioners are trying to push for that.
Nina (September 7, 2016 3:03 AM)
The report from the Joint Research Centre - JRC (not Joint Research Council which is a different entity) of the European Commission, from which the statistics are taken, is available on the JRC website:
Unwantedtattoos (November 27, 2018 4:17 AM)
Love your resources! I appreciate your details and depth writing style and all your eye cache points was so awesome.

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