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Science Vs podcast Tattoos: Are They Toxic?
Chapter One: Tattoos Under Attack
Hi, I’m Rose Rimler, filling in for Wendy Zukerman, and this is Science Vs. Today we’re talking about tattoos. Tattoos are more popular than ever[1], but lately, they’ve been getting some flak. Online we’re hearing that tattoos are toxic.
What’s a toxic guy tattoo? Upper chest roman numerals, that is always a toxic guy everyone knows one of those guys
No, not that kind of toxic! Like, poisonous
It turns out tattoos are actually pretty unhealthy for us
You’re constantly being poisoned by the toxins
If I went back in time, with the knowledge I have now, I would not have the tattoos I have
People are pointing to tattoo ink, saying, it’s full of stuff you don’t want in your body
Every single person who has a tattoo has metals leeching into their bloodstream
Mercury, lead, nickel, and other harmful heavy metals slowly releasing into your body, adding to your toxic burden, daily
Ultimately, they say, the consequences can be serious.
A new study has found it could increase your risk of developing cancer
21% chance of getting a malignant lymphoma with even small tattoos
And if this risk is real — it would affect a LOT of people. According to surveys, in the US[2] and Australia[3], a third of adults are tattooed ... and globally, that number is one in five[4] … So - are these people making a terrible mistake?? If you get a tattoo, are you poisoning yourself and upping your risk of cancer? And finally…has science found any benefits to getting inked? Because when it comes to tattoos, there’s a lot of…
Upper chest roman numerals
But then there’s science. Science Vs Tattoos is coming up after the break.
Chapter Two: Getting Under Our Skin
RR Welcome back. We are here to talk about tattoos. I'm Rose Rimler and I'm here with Science Vs editor and tattoo haver Blythe Terrell. Hi, Blythe
BT Hey Rose. Famed tattoo Haver.
RR Uh huh. So how many tattoos do you have? Where are they? Spill it.
BT So the first one I got, I got with my good friend, like when I was 18. We got, we both got flowers. It's just like, I'm 18, I have a flower. My husband and I have one that's kinda like, I love you in sign language, stylized. Uh, I have um, I have a stylized double helix on my ankle.
RR Very nerdy, very on theme.
BT And then my other one is, uh, the Batman logo. Um, but it is. The, it is the 1960s Batman.
RR I've always kinda been curious about it. Why? Why Batman?
BT So my initials are BAT. Oh. And so it's been like a running joke.
RR Oh, okay. So you're the Batman
BT revealed on this podcast.
RR Have you ever worried about your tattoos?
BT I mean, my mom worried that I wouldn't get jobs. Um, but like health-wise, I mean, I guess only to the extent that I was like, okay, is that, is this guy getting like a clean needle out of the package? But beyond that, beyond that, no. Has never come up for me.
RR Yeah, and I was pretty surprised when I saw stuff pop online about how tattoos being toxic. I don’t have any tattoos myself, but I know so many people who do so I really wanna know is this true or is just BS?
BT Yeah. I'm very curious to know what you found.
RR Yeah. So, you know, obviously tattoos have been around thousands of years[5] but interestingly. Scientists have only recently begun to study how the tattoo ink like interacts with our biology. This is kind of on the newer side of things. Um, scientists like Santiago Gonzalez, he is a toxicologist and immunologist at the University of Lugano in Switzerland.[6]
SG We actually started by chance, we were not primarily oriented on the, on the tattoo.
RR Here's what happened. Santiago needed to label mice for an experiment they were doing about the immune system. Um, the way they had been doing that was putting a tag on the mouse's ear, like tagging in their ears.
BT Mm-hmm.
RR Which is very common.
BT Yeah.
RR but
SG I, I, I, I never like it because it's a bit heavy and the animals, is a bit annoying for the animal.
RR So instead of tagging their ears, the scientists in his lab decided they were gonna try tattooing the animals in order to like mark them.
SG We basically have a tattoo machine, which is exactly the same as the, as the tattoo machine that is used by, by, by all the tattoo artists. And, we just, uh, do it normally like
RR Is it like teeny, teeny tiny?
SG It's, uh, yeah. It's, it's very small, so obviously you have to be very, very careful.
RR So they're chugging along, tattooing their mice, um, to do their next experiment. Which all seemed to work fine, but then something unexpected happened:
SG My students told me, you know, the lymph nodes of the animals are completely full with the ink of the tattoo.
BT Oh, gross
RR And just as a reminder, lymph nodes are structures in the body that are part of the immune system, they filter out lymph, which is fluid that comes from the blood. So Santiago’s team was looking at one of the lymph nodes in the mouse's leg near the foot, which is what had been tattooed. And they found that it got stained with the tattoo ink.
BT Oooh kay. That's not, that doesn't sound good.
RR It’s not what they expected. And it kind of messed up that experiment.
BT Oh, right. That's not what they were studying.
RR Right - they were just using the tattoos to label the mice for another experiment. But after seeing this, they decided to do an experiment[7] where they tattooed the mice … and then watched where the ink went[8] … in a more controlled way…
BT OK
RR So they did this all again, and then took photos of the lymph nodes two months later. Let me show you.[9] …
BT Ohhh, oh yeah, you can really see the ink in there!
RR It’s bright, it’s a few different colors of ink, you can see one mouse has a pretty bright blue lymph node, bulbous little goopy thing
BT So how did that happen?
RR Well, your body has these white blood cells, they’re called macrophages that go around gobbling up stuff that they think shouldn’t be there – so this is typically bacteria, broken bits of cells. And when you get a tattoo, macrophages in your skin, they go around and slurp up some of that ink[10]. And it turns out they’re also bringing that ink to the lymph nodes. Scientists have also seen this in people. We've had case studies documenting it ... Like if someone with tattoos goes in to get their lymph node biopsied for whatever reason, pathologists will sometimes find ink in the lymph node[11][12][13]. And Santiago's team also found this when they looked at lymph nodes from people[14] … which led him to conclude
SG When you are tattooing your skin, you are also tattooing your lymph nodes.
BT: OK, so we have tattooed lymph nodes … does that automatically equal some kind of a problem??
RR Well, it’s possible. If the lymph node is involved, that means the immune system is involved in some way. So Santiago’s team also checked levels of immune markers in the mice’s bodies, to see if they were elevated– that would suggest they were stressed out basically. These are molecules that are part of the body’s stress response to injuries or illness. And he did find that these molecules increased in both the lymph taken from that lymph node and in the mice’s blood[15]... But most of that activation went back to normal after a week or so from getting the tattoo. Which makes sense, of course you’d have a temporary inflammatory response to a bunch of needles in your skin. But there was one exception– a molecule associated with chronic inflammation. It’s actually called alarmin …
BT great. Yeah. What was the alarmin doing, Rose?
RR It was alarmed, it was raised even two months post-tattooing, which Santiago argues should have been past the initial healing phase of the tattoo[16].
BT Ah ha, OK, so how worried should we be about that?
RR Well, Santiago’s study was kind of exploratory — it showed some hints of some immune system weirdness, in mice … it wasn’t looking at long term issues in real people. So if we zoom out to other studies — we start to see that this activation of the immune system might be a problem for some people[17][18][19][20]. I read this case study a guy in Poland who had a full blown immune reaction to his tattoo four months after he got it. He lost his hair. He developed vitiligo.
BT What's that?
RR That's like a skin, a change in the color of your skin. And he had to get the tattoo essentially cut out of his arm[21]
BT Whoa.
RR There's another series of cases in Australia published recently about people who got this allergic reaction to their tattoo ink and it attacked their eyes, and some of them had vision loss[22].
BT OMG
RR Those examples are extreme, and not that common– but in general, we do see a lot of allergic reactions to tattoos, although typically it’s just confined to the skin.
BT Actually Rose the other day I was sitting with my husband, he looked at me and was like do your tattoos ever itch? I was like noooo do yours? And you know what else? He has some immune system stuff going on
RR Mmm another autoimmune thing going on
BT I’m wondering ohhh suddenly this change, Jacks’ tattoos are getting itchy, I wonder if it’s related!
RR Ok interesting, The best numbers I could find on how common this is, this sort of skin reaction to tattoos, comes from a survey of people with tattoos in Germany, and it found that about 9% of people reported persistent skin problems at least a month after they got their tattoo[23]. He might be in that unlucky sliver of people
BT Lucky in love, unlucky in tattoos
RR Obviously
BT Obviously laugh
RR Happens to a fraction of unlucky people, 9% in that German study. But there are other reasons to be concerned about tattoo ink that’s universal for everyone who gets tattooed. One is the the fact that a lot of tattoo ink contains chemicals that we think are possibly carcinogenic[24]. Hmm. And that includes black ink[25][26]. I noticed your tattoos are black
BT Most are black. Oh great, what are you gonna tell me about black ink? That it’s carcinogenic?
RR Um, black ink is basically soot.
BT So, so sorry. Great. So it's like, yeah, like if I'm, if I were a chimney sweep instead of a podcaster, that's the, is that what's going on here?
RR Yes right. But this IS what makes some people worried that tattoos might cause cancer
And we're gonna need some more science to figure that out. So we're gonna have to go to Sweden.
BT I'm ready. All right. And always ready.
RR And that is coming up after the break.
Chapter Three: Do tattoos cause cancer?
RR Welcome back. Uh, we're talking about tattoos today, and I'm here with Blythe Terrell. Hi Blythe.
BT Hey Rose.
RR So it turns out there are some reasons to be concerned about tattoos. Um, we know that the ink doesn't just stay put static in our skin. It's actually interacting with our immune system, getting into our lymph nodes. We know that some of the ink might be bad for us, might be even carcinogenic, but we wanna know like what are the consequences, right?
BT Besides just you feeling superior to me for not, 'cause you don't have tattoos and I do.
RR We know that people without tattoos are better. Um, but are they healthier? Um, I spoke about this with Christel Nielsen, she works at Lund University, Sweden[27]. She is an epidemiologist who focuses on environmental toxins, typically stuff like forever chemicals[28]. But a few years ago she got curious about potential toxins in tattoos.
CN And I might have one or two tattoos myself, so that triggered the interest.
RR What do you have?
CN I have a dragon on my arm and I
RR awesome.
CN And I was young in the nineties, so I might have a Chinese sign on my lower back.
RR Chinese character on your lower back? I'm not, I'm just laughing because
CN yeah. You laugh. It's the stereotype, but I don't have a tribal, I have to say that.
RR what does the Chinese character mean?
CN It's supposed to mean horse because I'm born in the year of the horse. Uh, but I showed it to my daughter's friend who knows Chinese, and she said. I've never seen that sign before,
RR Oh, no.
KN So I don’t know what it means.
BT This is the classic tattoo horror story of, of the nineties.
RR Yeah.
BT So she's relatable, is what I'm saying?
RR Yes, she's very relatable. Um, so she decided to learn Chinese. No, no, she didn't. She, um, decided to look into tattoos and health.
BT I was ready to go with you on the journey.
RR Um, she zoomed in on cancer for the reasons we talked about before, the potential carcinogenic ink. And also we know that chronic inflammation can lead to cancer[29][30]. So she dove into that beautiful Scandinavian public health data that we love so much here at Science Vs
CN In Sweden, we have this. Very, very, in terms of research useful national registries where we all end up, whether we like it or not. So it's, it has full population coverage. Um, and especially for cancer. We have the National Cancer Registry[31], so if you get diagnosed with cancer in Sweden, any cancer, you will end up there.
So she and her team decided to focus on two types of cancer that they could see plausibly being connected to tattoos.
Mm-hmm. Um, skin cancers, including melanoma[32], it's kind of obvious, but also lymphoma.
That's cancer of the lymph system. BT Right. 'cause we know that the ink is in the lymph system[33].
RR Right.
BT So that makes sense. Okay. Right. Got it.
RR And so they pulled the records of everyone in Sweden who had been diagnosed with those cancers between the ages of 20 and 60[34][35][36], and then they set out to find who among them had tattoos.
CN So we contacted all of them and. I mean, lymphoma is a severe disease, so not everyone who were diagnosed 10 years ago were still alive. Uh, and in that case, we contacted their next of kin[37] with the main point then of, of understanding whether the, the relative had had tattoos or not.
RR And they also gathered a group of, um, like matched. People who did not have cancer. Um, sort of like matched controls[38][39].. Mm-hmm. And they sent out questionnaires to them as well. A lot of lifestyle stuff, but also like lots of questions about tattoos[40]. Not just like, do you have a tattoo, but how many do you have? How big is it? When did you get it? Where'd you get it? All that kind of stuff. Um mm-hmm. People really got excited about this. They sent Christel, like all these emails and stuff, like they wanted to tell her all about their tattoos.
CN It's nice to get to know your participants in a way. Some still send me postcards. It really, it's really, really sweet.
RR So the data started coming back, um, and Christel was working closely with one of her co-authors. Um, but this is during the pandemic. They weren't together that much. Um, so one day Christel found herself just crunching the data alone
CN I was, you know, in my house, it was just me. And I had the data there and I just, I just needed to have a look. And then there were the preliminary results and I just threw myself at the phone and told her that, well, we might actually have something here.
BT. Whoa. Oh, no.
RR Yeah. So she found something when it came to cancer risk. So first lymphoma.
CN we saw an increased risk of, of lymphoma among those with tattoos compared to those who did not have tattoos. Their risk was 20% increased,[41]
RR They also found about a 30% increased risk of melanoma[42].
BT Wow. That seems big. Is that big?
RR Well…here’s Christel on that
CN We're talking about relative risk increases. So the risk on an individual level is small
CN People shouldn’t be freaking out
BT Mm. Because it's like, it's that sort of situation where a 20% increase risk is serious, but the original risk might be very small. So the new risk, even 20% higher is still not like. Astronomical, right? Is that the idea?
RR Right exactly. So like in the US according to the National Cancer Institute, the absolute risk of getting lymphoma is about 2.2%[43][44]. So if we apply Christel's finding to that, um, it suggests that a tattoo might make that risk go from 2.2 to 2.64%. And then for melanoma it would be like starting at 2.2%[45], going to 2.9%. Like sort of the average person.
BT Mm-hmm. Right. Right. Which is not, I mean. Which is not nothing. Yeah. So if you're a person who, is already at an increased risk, you might have to factor that in.
RR Exactly. And there are a couple other studies that have looked into this, and not all of them find this link to cancer[46][47]– but the strongest and biggest studies do find this link, like a similar one in Denmark[48][49][50].
BT Okay. Well, but what about like, is there any reason to think there might be some confounders, like to people who have tattoos tend to have a different kind of lifestyle or like be slightly be more likely to party or engage in other behaviors, Rose, that like might contribute to cancer risk or that kind of stuff.
RR So the, these studies do try to adjust for that as best they can. Um, but yeah, it's probably not perfect, and there is some evidence that, uh, people who have tattoos might do some on the whole are more likely to do some risky behavior compared to people who don't have tattoos[51][52]. So smoking[53] is something that has come up in the literature. Um, the thing is like these cancers are not particularly associated with smoking.
BT Okay. So it sounds like you think there's something here.
RR Yes, I do. And I do. Um, partly 'cause I think the studies. Christel's and the, the other study from Denmark are good studies. And also it seems like we have a mechanism that's plausible. It just, it does make some sense,
Chapter Four: Should You Get Them Lasered Off?
BT Rose, should I get all my tattoos removed? Should I get, because you can, right? There are ways to get tattoos removed?
RR Yeah, you can get them removed with lasers. Um, and you might want to do that if you're freaked out about what I just said. Or you know, you got a Chinese character on your lower back and you actually dunno what it means. And in fact, outside of this, studies do find that something like 20 to 25% of people regret at least one tattoo[54][55][56]. Christel says, the thing about that is for as little as we know about the effect of tattoo ink on the body, we know even less about what happens when we shoot lasers at tattoos.
CN So what people need to know is, I mean, don't laser tattoos and they evaporate into thin air. I mean, that's not what happens. They need to get through the body to get out in the other end, basically.
RR The laser blasts the ink into smaller fragments that the immune system then can go and clean up. But you're still like getting your immune system to, you know, you're triggering an immune response[57]. Mm. And you're also changing the molecules. Um, and some of those are worse than the original molecules in the ink. So, for example, we know that a lot of the colors in tattoo inks are made with, um, nitrogen groups called azos. When Azos are broken apart, they can form compounds that we know are carcinogenic[58].
CN So we might set off a cascade of exposure to something that we don't know what it is, but it might be worse than the original exposure.
RR might be. I mean, there's a lot we don't know[59]. We should be getting more information about tattoos. Generally over the next five or 10 years. Christel is gonna keep studying people[60]. She's got this cohort, you know, she's gonna keep studying them. There's another project that's backed by the World Health Organization that's getting off the ground following people with tattoos over a number of years[61]. So we’re gonna find out more about tattoos and health.
CN I think that we as a society, we will continue to get inked and then we need to make sure that it's safe to do it.
Chapter Five: The Benefits of Tattoos
BT Absolutely. And I think the, what we do in the show right, is like, try to give you the information to like make that decision for yourself, you know, we're not cops. Um, but even when I think about it, I'm like, I knowing all this, like, I don't know, you know, like maybe I still would've gotten my tattoos.
RR Yeah?
BT Because I like them uhhuh. You know what I mean? Like, I'm not sure if knowing this would've been quite enough. For me to be like, never.
RR . Right. Well, yeah. I mean, and the thing is like with, with anything that we talk about, it's always like risk versus benefit.
BT benefit – looks cool.
RR No there are real benefits Blythe! It’s more than just looking cool. And I have one final guest to introduce you to, to tell us a little bit about this. His name is. Viren Swami. He’s a professor of social psychology at Anglia Ruskin University in the UK[62].
VS Being tattooed or being able to get a tattoo is a small marker of agency says, I am allowed to own my own body and do what I want with my body. Historically, essentially tattoos were the preserve of what psychologists have called out groups. And out groups we simply mean marginalized communities[63][64].
RR So, like in the west and in communities colonized by the west, tattooing has been associated with being in an out group, think of sailors in the 1700s[65]. But it's mainstream, uh, in other parts of the world, like in Polynesia[66][67]. Um, and even though today in the west, tattoos are not as stigmatized, researchers still finds an echo of that motivation. So this is interesting, the demographic in the US that is most likely to get tattooed, um, this is according to a Pew research survey from a few years ago. Queer women. 68% of people who identify as queer women have at least one tattoo[68].
BT Interesting
RR and that makes a lot of sense to Viren – it goes back to the idea of being part of an outgroup.
VS I think any community that has a history of marginalization will try and reclaim the body in some way. It's also the same reason why some researchers have talked about how women who have been, who have had a history of sexual or physical abuse tend to get tattooed[69][70][71]. Again, it's a way of reclaiming the body and saying, this body is mine.
RR And we do have some evidence that getting tattooed can help people feel better about themselves. A few years ago, Viren went to a tattoo shop in London and he surveyed people before they got their first tattoo and after, and then followed them up a little bit later too. He did stuff like he was assessing their self-esteem[72]. Mm-hmm. He asked them, how do you feel about your body? How do you feel about how you look? Um, and it turns out that after they got their tattoo …
VS people reported being happier with their bodies, appreciating their bodies, more[73], feeling like they were more unique as a result of getting tattoos and feeling lower anxiety about their appearance
Another study found this too. This study actually had college students design a temporary tattoo that an artist painted on them. It lasted a couple weeks[74] And they measured their like self-esteem and, and how they felt, um, before and after that temporary tattoo. And it did also gave 'em a boost[75].
BT Oh, that's fun.
RR And I think it’s telling that most people don’t regret their tattoos even years later– remember that stat I told you earlier? Maybe 20% regret? That means 80% don’t!
BT I’m among the 80%
RR Yeah I was gonna ask you after all that info, your husband’s itchy arm.
BT Yeah I should tell him to keep an eye out for anything else that might be going on that’s unnerving here. I think for the, on generally speaking, I, I go into things thinking like, uh, it's an internet meme. It's toxic. Don’t do it. And so I expect it to maybe not be true. So I think it's really useful to know that like in some, that maybe there is something there. Mm-hmm. I don't know. Overall, I guess it doesn't freak me out about the tattoos that I have now.
RR Yeah. But let me ask you this, would you get another one?
BT I don't know.
RR Do you want to, do you have any planned ?
BT I had been thinking about it. I've had like a, a particular stegosaurus in mind for a while.
RR Of course! Well I will say, um, one thing we didn't talk about was like are you more at risk if you have more tattoos?
BT Yeah. Well that's a, yeah.
RR And Christel’s study found, no, but the Denmark study found Yes. Or like bigger tattoos. And Christel actually thinks that her finding was sort of an artifact of the way she asked the questions. So she thinks it's very possible the more tattoos or the more ink, if you get like a really ink-filled tattoo. Very likely could have a higher risk associated with it. We don't have all the receipts for that.
BT Mm-hmm.
RR Something to consider.
BT Ok I can do that Rose I can consider it.
RR Consider it.
BT Thank you.
RR Thank you. And that’s Science Vs.
RR Blythe, there are 77 citations in this episode.
BT Wow. Okay.
RR And you can tell folks where to find them Blythe.
BT Yes. Uh, you can find them in our transcript, which we link to in our show notes.
RR All right.
CREDITS
This episode was produced by Rose Rimler, with help from Blythe Terrell, Ekedi Fausther-Keeys, Meryl Horn, and Michelle Dang. Wendy Zukerman is our executive producer. We’re edited by Blythe Terrell. Fact checking by Diane Kelly. Mix and sound design by Bumi Hidaka and Bobby Lord. Music written by Bobby Lord, Bumi Hidaka, So Wylie, Emma Munger and Peter Leonard. Special thanks to all the experts we spoke with for this episode, including Dr. Signe Clemmensen, Prof. David Kriebel, Dr. John Swierk, Natacha Cingotti, Dr. Sandrine Henri, Prof. Chris Lynn, and Tricia Allen.
Science Vs is a Spotify Studios Original. Listen for free on Spotify or wherever you get your podcasts. Follow us and tap the bell for episode notifications.
[1] Tattoos have become increasingly popular particularly among younger people. In Europe, the prevalence of tattoos and permanent make-up (PMU) is estimated to be 10–20% among the general population, steadily increasing over the past decades
[2] Pew survey USA 2023: Overall, 32% of adults have a tattoo themselves, including 22% who have more than one.
[3] In the last five years, tattoos have become increasingly prevalent among Australians. Today, three in ten Aussies (30%) have a tattoo, compared to 20% in 2018.
[4] The overall prevalence of tattooed people was 18.5%: 10.6% reported one tattoo and 7.9% >1 tattoo, Table 1)
[5] by far the best-known example of a tattooed mummy is the naturally preserved remains of the Tyrolean Iceman known as Ötzi. Following his death around 3250 BC (Kutschera and Müller, 2003) Ötzi was entombed beneath an alpine glacier, where a combination of glacial meltwater and extreme cold resulted in the natural mummification of his body and preservation of his clothes and tools. Following his accidental discovery in 1991 Ötzi became an international archeological sensation, and more than two decades of scientific analysis have generated a fantastic body of data on his life, health, environment, and the circumstances surrounding his death…Ötzi bore 61 tattoo marks across his body (Samadelli et al., 2015), including on his left wrist, lower legs, lower back, and torso (Fig. 1). These include 19 groups of lines, ranging from 1 to 3 mm in thickness and 7 to 40 mm in length.
[7] Santiago’s study: This study aimed to characterize immune responses to tattoo ink accumulating in draining LNs and to determine how its presence modulates vaccine response. We used C57BL/6 J, CX3CR1-GFP, and CD11c-YFP mice, bred under SPF conditions, to examine the distribution and immune effects of tattoo inks following footpad tattooing. Mice (6 to 12 wk) were tattooed with commercial inks or PBS control.
[8] To evaluate the transport of unretained ink from the skin area to the draining LN,... we performed intravital imaging following footpad tattooing (Fig. 1B). We observed that the ink disseminates exclusively via popliteal lymphatic vessels, reaching an initial peak at 10 min following tattooing (Fig. 1 Cand D). Furthermore, the transport of ink via the lymphatic system was associated with a prominent accumulation in the popliteal LN (pLN) observed at 24 h posttattooing (p.t.) for all the tested inks
[9] Fig1I)Snapshots showing the tattooed area on the mouse footpad and the ink accumulation in the draining LNs at 2 mo after tattooing with commercial True Black, Bright Red, or Pure Green inks.
[10] we conducted the first systematic analysis of the identity, origin, and dynamics of the skin myeloid cells that are capable of capturing and retaining tattoo pigment particles. The tattooing process consists of inserting water-insoluble pigment of the desired color into the dermis layer of the skin. Tattoo pigments are primarily metal salts in the submicrometer range. Immediately after tattooing, a fraction of pigments is shed with the epidermis or transported away from the dermis via lymphatic vessels. We demonstrated that the pigment particles that remain at the site of injection and cause the long-term tattoo color were exclusively found within dermal macrophages…in physiological conditions, when tattoo-pigment-laden macrophages die during the course of adult life, neighboring macrophages recapture the released pigments and ensure in a dynamic manner the macroscopic stability and long-term persistence of tattoos
[11] Case report : Histological examination of the lymph node demonstrated normal lymphoid tissue and the presence of pigmented macrophages due to tattoo ink.
[12] Case report Intraoperatively, a heavily pigmented sentinel lymph node is identified. The clinical impression is highly suspicious for metastatic disease and the tissue was sent to pathology for examination….Frozen-section examination shows lymph node tissue with normal architecture. There are benign histiocytes within the lymph node, with black, nonpolarizable, coarse granules in the subcapsular and sinusoidal areas.
[13] Patients were retrospectively reviewed from medical records and clinicopathologic data was collected. A total of 52 LNs were retrieved from 15 patients for sentinel mapping and 29 of them had tattoo pigmentation on pathologic evaluation.
[14] Remarkably, we observed a similar distribution in all the human samples from LN biopsies evaluated collected from deidentified patients who had a tattoo in the LN-drained area at least several months before the biopsy (SI Appendix, Fig. S1D).
[15] To further characterize the inflammatory response, we collected the lymph from the pLN during the first 240 h following tattooing with black ink, and we measured the levels of inflammatory cytokines and chemokines at different instances….To determine whether the observed inflammation also occurs systemically, we measured the expression of inflammatory mediators in blood at early (first 5 d) and late (2 mo) times posttattooing. Interestingly, we found that the early peak of inflammation previously described was also detected systemically, with elevated levels of the inflammatory cytokines IL-6, TNF-α and IL-1β, and the chemokines CCL2, CXCL9, and CXCL13, measured in the blood during the first 24 h following tattooing with all three tested inks
[16] However, the levels of the alarmin IL-1α remain elevated in the blood from all tattooed groups 2 mo after tattooing
[17] In the same survey, the allergenic metals Cr, Ni, and Co presented concentrations well above the safe limit in 62.5, 16.1, and 1.8% of the cases, respectively.
[18]Sensitivity to a particular pigment can manifest in several ways including allergic contact dermatitis and photoallergic dermatitis. Furthermore, tattoo ink reactions can be classified as acute inflammatory reactions, allergic hypersensitivities, and granulomatous, lichenoid,and pseudolymphomatous types of reactions. Histology shows acanthosis, spongiosis, and a lymphocytic perivascular infiltrate
[19] In clinical studies, allergic reactions in tattoos may start after a few weeks or even after months or years. An early debut points to an allergen already present in the tattoo ink. Conversely, late debut rather indicates the formation of an allergen over time due to local metabolic breakdown or photodegradation.
[20] “Rush phenomenon” with concomitant reaction in many other black tattoos, triggered by a recent tattoo with a papulo-nodular reaction, was observed in 70% in the sarcoidosis group and 28% in the non-sarcoidosis group, indicating a predisposing factor which may be autoimmune and linked with sarcoidosis.
[21] This case report describes a 36-year-old Caucasian male who developed erythroderma, alopecia, anhidrosis, and vitiligo as complications of a red ink tattoo, marking a rare and previously unreported case of such extensive reactions. Four months after getting the tattoo, the patient began to develop itchy eczematous changes, which progressed to erythroderma over several months, along with alopecia universalis and anhidrosis. After months of ineffective treatment with glucocorticosteroids, cyclosporine, methotrexate, and acitretin, patch tests confirmed hypersensitivity to possible components of the red tattoo ink, prompting surgical removal of the inflamed tattoo fragments. Unfortunately, aside from resolving the erythroderma, this did not improve the patient’s clinical condition, and he developed vitiligo….
[22] Tattoo-associated uveitis (TAU) is attributed to an immune response triggered by tattoo pigments, particularly black ink. Inflamed tattoos are most commonly associated with bilateral anterior uveitis, but posterior involvement including optic disc swelling, cystoid macular oedema, and retinal detachment have also been reported amongst the approximately 39 TAY cases described…The uveitis can manifest months to years after tattooing and has been labeled a delayed hypersensitivity reaction….Forty cases were submitted from three Australian states.
[23] After tattooing, the people described skin problems (67.5%) or systemic reactions (6.6%). Four weeks after tattooing, 9% still had health problems. Six percent reported persistent health problems due to the tattoo, of which females (7.3%) were more frequently concerned than males (4.2%). Colored tattoos provoked more short-term skin (p = 0.003) or systemic (p = 0.0001) reactions than black tattoos. [Sci-hub]
[24] Depending on the tattoo colour, polycyclic aromatic hydrocarbons (PAHs), primary aromatic amines (PAAs) and metals can be found in tattoo inks. Exposure to these substances is associated with a higher risk of various types of cancer including lung, kidney, liver, skin and bladder - depending on the specific substance (Table 1) [2]. However, their classification mostly relates to the oral, dermal or respiratory uptake of the substance as occurring in industrial work places (e.g. welding or dying), by inhaling tobacco or wood smoke or applying other consumables like cosmetics. The exposure route of tattooing, where the ink is injected directly into the dermis, differs considerably from uptake routes normally used for evaluating the risks of substances.
[25] Polycyclic aromatic hydrocarbons (PAHs) are a class of chemicals that occur naturally in coal, crude oil, and gasoline. They also are produced when coal, oil, gas, wood, garbage, and tobacco are burned.
[26] There are likewise concerns around the use of TiO2 (PW6) and carbon black in tattoo inks, both of which are used by all nine ink manufacturers in this study, with TiO2 found in 21 of the 54 inks. Both pigments are classified as possible carcinogens in humans, possibly via the formation of reactive oxygen species that may lead to lung cancer. Particle sizes less than 100 nm are a concern with both TiO2 and carbon black, due to the potential to cross blood-tissue barriers. Finally, polycyclic aromatic hydrocarbons (PAH) are a known contaminant in carbon black, with concentrations as high as 201 mg/kg. PAH are generally considered to be carcinogens.
[29] Overall, chronic inflammation may provide a microenvironment that facilitates the emergence and spread of cancer.
[30] Chronic inflammatory mediators exert pleiotropic effects in the development of cancer. On the one hand, inflammation favors carcinogenesis, malignant transformation, tumor growth, invasion, and metastatic spread; on the other hand inflammation can stimulate immune effector mechanisms that might limit tumor growth.
[31] Around 80,000 malignant cancer cases in Sweden are reported to the Register each year. This number refers to reported tumours, and not the number of individuals. It includes information such as personal ID number, gender, residence at the time of the diagnosis, reporting hospital or clinic, date of diagnosis and clinical and morphological diagnosis, as well as tumour extent at the time of diagnosis.
[32] Melanoma is a disease in which malignant (cancer) cells form in melanocytes (cells that color the skin)
[34] We performed three case–control studies, leveraging national Swedish registers and a questionnaire developed specifically for exposure assessment of tattoos, to investigate potential associations between tattoos and malignant melanoma, cutaneous squamous-cell carcinoma and lymphoma. The survey was performed in 2021.
[35] We performed a case–control study where we identified all incident cases of malignant lymphoma diagnosed between 2007 and 2017 in individuals aged 20–60 years in the Swedish National Cancer Register.
[36] In this population-based case-control study nested within the Swedish total population, all individuals with a diagnosis of nevus with severe atypia, cutaneous melanoma in situ or invasive cutaneous melanoma aged 20–60 years at diagnosis in 2017 (i.e. the index year) were identified in the National Cancer Register.
[37] To capture the age group that is most likely to be tattooed, we restricted inclusion to individuals aged 20–60 years at the time of diagnosis. Deceased cases were identified in the National Cause of Death Register and, if cases were deceased, next-of-kin was included to mitigate the impact of potential survivorship bias.
[38] Three age- and sex-matched controls per case were randomly sampled from the population at risk on the date when the case was diagnosed (hereafter referred to as the index date).
[39] Three matched controls per case of the same age and sex were randomly sampled in the Total Population Register on the index date using incidence density sampling with person-time as the underlying timescale.
[40] Briefly, tattoos were defined as permanent designs received for decorative, cosmetic (defined as permanent make-up, semi-permanent makeup, and microblading), or medical (defined as skin restoration after mastectomy or burn lesions) purposes. Exposure was assessed as presence or absence of any tattoo, and respondents were explicitly asked to consider also removed tattoos. Respondents provided their age at first tattoo and tattoo characteristics including colours, total area of tattooed body surface (<1; 1–5; or >5 hand palms), skill level of tattooer (professional; amateur), and geographical region of tattooing. To mitigate the risk of selective participation, we informed participants that the purpose was to study new lifestyle factors in relation to cancer and other diseases, and included questions about several types of body modifications.
[41] In the matched analysis, tattooed participants had a higher adjusted risk of malignant lymphoma than nontattooed participants (IRR = 1.21; 95% CI 0.99–1.48)
[42] https://pubmed.ncbi.nlm.nih.gov/41284183/ We observed an adjusted relative risk of CM in tattooed compared to nontattooed individuals of 1.29 (95% confidence interval [CI]: 1.07–1.56).
[43] Approximately 2.0 percent of men and women will be diagnosed with non-Hodgkin lymphoma at some point during their lifetime, based on 2018–2021 data, excluding 2020 due to COVID.
[44] Approximately 0.2 percent of men and women will be diagnosed with Hodgkin lymphoma at some point during their lifetime, based on 2021–2023 data.
[45] Approximately 2.2 percent of men and women will be diagnosed with melanoma of the skin at some point during their lifetime, based on 2018–2021 data, excluding 2020 due to COVID.
[46]The participants included in this study were taken from two population-based case–control studies in British Columbia, Canada, with cases ascertained from the BC Cancer Registry, and controls ascertained from the Provincial Health Insurance Plan. A total of 1,518 participants from the NHL study (737 cases) and 742 participants from the multiple myeloma study (373 cases) were included in the analyses. No statistically significant associations were found between tattoos and risk of NHL or multiple myeloma after adjusting for age, sex, ethnicity, education, body mass index, and family history.
[47] All incident cases of in situ and invasive melanoma diagnosed in Utah between January 1, 2020, and June 30, 2021, ages 19-79 years old were identified by the Utah Cancer Registry using rapid case ascertainment In a population-based case-control study with 1167 melanoma cases (566 in situ; 601 invasive) and 5835 frequency-matched controls, we examined tattooing and melanoma risk using multivariable logistic regression to calculate odds ratios (ORs) and 95% confidence intervals (CIs)...Although ever receiving a tattoo was not strongly associated with melanoma risk, heavier tattooing exposure was associated with decreased risk. Overall melanoma risk was decreased among individuals who had received 4 or more tattoo sessions (OR = 0.44, 95% CI = 0.27 to 0.67) and individuals who had 3 or more large tattoos (OR = 0.26, 95% CI = 0.10 to 0.54) compared with those who were never tattooed. Invasive melanoma risk was also decreased among individuals who received their first tattoo before age 20 (OR = 0.48, 95% CI = 0.29 to 0.82) compared with never tattooed individuals.
[48] Importantly, we found that common risk factors for cutaneous melanoma, such as high UV exposure and light skin, were more common among cases than controls, which suggests that our results are valid.
[49] We aim to study the potential association between tattoo ink exposure and development of certain types of cancers in the recently established Danish Twin Tattoo Cohort….In the case-control study, individual-level analysis resulted in a hazard of skin cancer (of any type except basal cell carcinoma) that was 1.62 times higher among tattooed individuals (95% CI: 1.08-2.41). Twin-matched analysis of 14 twin pairs discordant for tattoo ink exposure and skin cancer showed HR = 1.33 (95% CI: 0.46-3.84). For skin cancer and lymphoma, increased hazards were found for tattoos larger than the palm of a hand: HR = 2.37 (95% CI: 1.11-5.06) and HR = 2.73 (95% CI: 1.33-5.60), respectively. In the cohort study design, individual-level analysis resulted in a hazard ratio of 3.91 (95% CI: 1.42-10.8) for skin cancer and 2.83 (95% CI: 1.30-6.16) for basal cell carcinoma.
[50] We conducted a population-based case–control study with incident cancer cases identified by the Utah Cancer Registry and controls selected from the Behavioral Risk Factor Surveillance System (BRFSS) survey. …We examined tattooing and risk of hematologic cancers in a population-based case–control study with 820 cases diagnosed 2019–2021 and 8200 frequency-matched controls, ages 18–79 years….Though there were no clear patterns of associations between ever receiving a tattoo and risk of HL, NHL, or myeloid neoplasms overall, in analyses restricted to ages 20–60 years, ever receiving a tattoo (OR 2.06 [95% CI 1.01, 4.20]) and receiving a tattoo 10+ years prior (OR 2.64 [95% CI 1.23, 5.68]) were associated with an aggregated group of rarer mature B-cell NHLs. We also observed elevated risks for a 10+ year latency for myelodysplastic syndromes and chronic myeloid leukemia (OR 1.48 [95% CI 0.40, 5.41], and OR 1.24 [95% CI 0.45, 3.43], respectively).
[51] A recent study revealed that while any form of body modification is associated with risktaking behavior and greater use of marijuana or alcohol, other previously perceived stereotypes of social or personal attributes or pathology, such as dysfunctional family units, rare church attendance, or previous encounters with jail or prison, were not substantiated. Indeed, when compared with their peers without body modifications, those with tattoos or piercings are just as likely to have similar childhood experiences and come from similar family and social backgrounds [14]. [Sci-hub]
[52] As compared to individuals who did not subsequently obtain a tattoo, individuals that did were significantly less conscientious, more extraverted, more willing to engage in sexual relations in the absence of commitment, and had higher scores on sensation seeking, Need for Uniqueness, and distinctive appearance investment. The effect sizes of uncovered differences were small-to-moderate (ηp2 = .07–.14).
[53] See bottom pg 13 https://www.google.com/books/edition/Tattooed_Skin_and_Health/OB8UCAAAQBAJ?hl=en&gbpv=1&dq=smoking&pg=PA6&printsec=frontcover
[54] 16.2% of participants regret a current tattoo and 21.2% are interested in having 1 or more tattoos removed
[55] Survey of 501 subjects over 18 years of age with at least one tattoo from 38 American states revealed the following rates of complication or characteristics: pain, 3.8 %; infection, 3.2 %; pruritus, 21.2 %; regret, 16.2 %; wish to have the tattoo removed, 21.2 %; and received the tattoo while intoxicated, 21.2 %, [Sci-hub]
[56]PEW Research 2023: Most tattooed Americans do not regret getting a tattoo. But about a quarter (24%) say they ever regret getting one or more of their tattoos.
[57] The laser facilitates the fragmentation of ink particles into dimensions suitable for translocation within bodily tissues and vascular structures. The ink particles are engulfed by the immune system, particularly macrophages, which subsequently transport them across various tissues and eliminate them via the excretory system.
[58] Five of the pigments identified in this study contain azo functional group (PR170, PR210, PR112, PY74, and PY14), leading to potential concerns over the release of primary aromatic amines (PAA). Many PAA, such as o-toluidine, are known or probable carcinogens in humans.
[59] "Based on the current extensive experience with laser tattoo removal, there is no justification to claim that this procedure can potentially induce cancer."
[60] https://bmjopen.bmj.com/content/13/5/e069664 The Swedish Tattoo and Body Modifications Cohort (TABOO) was established by pooling the controls from these studies. It constitutes the largest population-based cohort with detailed exposure assessment of tattoos and other body modifications.
[61]To investigate the potential carcinogenicity of tattooing that entails the intradermal injection of hazardous chemicals, the Cancer Risk Attributable to the Body Art of Tattooing (CRABAT) cohort was established within the French national cohort Constances
[63] Historically, tattoos were associated with out-groups, such as bikers or prisoners, who were
stereotyped as aggressive. Indeed, some scholars likened tattoos to an “exoskeletal defence” (Hawkins & Popplestone, 1964, p. 500), a symbol of physical strength and aggression. Similarly, the visibility of tattoos in the punk movement of the 1980s is often interpreted as a means of protesting conservative bourgeois values (Swami & Harris, 2012).
[64] Historically and contemporarily, tattoos have been used to signify philosophical positions, identity formation, life transitions and group membership. For example, Atkinson (2003: 197) reports “Straightedgers in Canada indicate that tattooing is not constructed as a flamboyant form of social protest by them, but rather a highly controlled method of cultural dissent.” [Sci-hub]
[65] https://www.history.navy.mil/browse-by-topic/heritage/customs-and-traditions0/sailor-s-tattoos.html#:~:text=Although%20there%20are%20indications%20that,seamen%20in%20Europe%20and%20America.
[66] Ultimately, Mallon and Galliot favor Samoan oral tradition as the root of tatau and its mapping of the two houses held responsible for carrying on the tradition. These two genealogical lines have become the gatekeepers of tatau. As tatau becomes more popular among non-Samoans, and with the invention of new social media, both of these lines are crucial in preserving traditional practices and ceremony.
[67]“Traditionally, tatau served as a form of ID or social rank, keeping track of the genealogy of the family, and representing important milestones,” says Samuela
[68] 2023 Pew survey USA: 38% of women have at least one tattoo, compared with 27% of men. This includes 56% of women ages 18 to 29 and 53% of women ages 30 to 49. Around half of lesbian, gay or bisexual Americans (51%) have at least one tattoo. The share is especially high among women in this group: 68% are tattooed, including 55% who have more than one tattoo. By comparison, 31% of straight Americans have at least one tattoo.
[69] findings of the current study indicate three alternative explanations for choosing tattoos. Survivors of sexual assault often indicate that they are purposefully turning away from traditional medical institutions or personnel and instead seeking alternative means of processing their trauma. The current findings indicate that women may in fact be deviating from more traditional psychotherapies. Current research acknowledges that traditional, patriarchal forms of therapy are not adequately meeting the needs of some survivors of sexual trauma for healing. Perceiving that they are not getting the care they need and facing social stigma from medical institutions, sexual assault survivors are instead turning to alternative forms of healing. These alternative forms of healing include tattoo and other forms of body modification. [Sci-hub]
[70] this study sought to better understand how the tattoo environment operated as a therapeutic healing space by conducting a secondary data analysis on qualitative interviews conducted with ten survivors of sexual trauma and seven tattoo artists.
[71] In general, there were more significant associations between body modifications and reported abuse among females (48.2%) than males (29.2%). However, differences in significant associations by type of body modification (39.3% for physical abuse, 38.1% for sexual abuse, 42.9% for mental abuse, and 34.5% for general emotional abandonment) were not large.
[72] The present study employed a prospective design in which respondents completed a questionnaire-based survey immediately before (Time 1) and after (Time 2) obtaining a tattoo, as well as three weeks after obtaining their tattoo (Time 3). At Time 1, participants completed state and trait measures of body image, appearance anxiety, motivations for obtaining a tattoo, perceptions of uniqueness, and self-esteem. At Time 2, participants completed state measures of body image and appearance anxiety, as well as a measure of their satisfaction with the new tattoo. Finally, at Time 3, participants completed trait measures of body image and appearance anxiety, perceptions of uniqueness, and self-esteem
[73] Results for body appreciation showed that there was a significant increase in body appreciation at Time 3, F(1, 80) = 20.48, p < .001,
[74] Participants chose their own monochromatic tattoo design, though they were to be no larger than the size of a cell phone; no other limits were placed on the content of the tattoos. An artist applied the ink freehand after technical and ethical training. By allowing participants to choose a design they would be comfortable wearing for two weeks, this experiment mirrored what it is like to receive an actual tattoo, since tattooed individuals typically determine the content of their own body art.
[75] These results also support the initial proposition that a tattoo can create higher levels of self-esteem, thus explaining the results found by Hill, Ogletree, and McCrary (2016), while also offering a stronger method for assessing self-esteem of tattooed individuals.