It takes a brave soul (in some cases, emboldened by a strong drink or two) to get a tattoo. And while people may spend time considering what design to have pierced onto their bodies, few may consider exactly what happens to the ink once it is injected under their skin.
In fact, scientists are still investigating that question.
To make a tattoo permanent, a tattoo artist punctures the skin with hundreds of needle pricks. Each prick delivers a deposit of ink into the dermis, the layer of skin that lies below the epidermis, which is populated with blood vessels and nerves.
Once the ink is inserted into the dermis, it doesn't all stay put, research is finding. Some ink particles migrate through the lymphatic system and the bloodstream and are delivered to the lymph nodes. Research on mice suggests some particles of ink may also end up in the liver.
"When you inject particles into the skin, some travel to the lymph nodes within minutes," Ines Schreiver, a chemist with the German Federal Institute for Risk Assessment in Berlin,told Live Science. [5 Weird Ways Tattoos Affect Your Health]
Where the ink goes
To be clear, most of the tattoo pigment stays put after a person gets a tattoo. The ink that's not cleared away by special repair cells, called macrophages, stays in the dermis within trapped macrophages or skin cells called fibroblasts. It then shows through the skin, perhaps spelling out "Mom" or featuring that eagle design you spent weeks choosing.
"Normally, the ink doesn't migrate too far from where it's injected," Dr. Arisa Ortiz, a dermatologist and director of laser and cosmetic dermatology at the U.C. San Diego Health, told Live Science. "For the most part, it is engulfed [by skin or immune cells] and then kind of sticks around in the dermis."
But researchers are now taking a closer look at the tattoo ink that does travel to other parts of the body, particularly the lymph nodes.
Schreiver was part of a team of German and French scientists that performed the first chemical analyses on tattoo ink collected at human lymph nodes. The researchers analyzed the lymph nodes of four cadavers that had tattoos, as well as two cadavers that had no tattoos, which served as controls.
The researchers pointed out in their study, published in the journal Scientific Reports (opens in new tab), that "pigmented and enlarged lymph nodes have been noticed in tattooed individuals for decades." Those reports came mostly from pathologists who began noticing unusual coloring in lymph node biopsies taken from tattooed patients.
For example, a 2015 reportin the journal Obstetrics and Gynecology described how doctors at first thought a woman's cervical cancer had spread to her lymph nodes. After surgically removing the nodes, the doctors realized that what had appeared to be malignant cells were actually tattoo ink particles.
"I was very curious about the chemical side effect of tattoos," Schreiver said. "I think people are aware that you can get skin infections from a tattoo, but I don't think most are aware that there may also be risks from the ink."
To investigate these side effects, Schreiver and her colleagues used several different tests, to analyze what forms of tattoo ink were collecting in the lymph nodes and any damage that might have resulted. Among their findings was that nanoparticles — particles measuring less than 100 nanometers across — were most likely to have migrated to the lymph nodes.
Carbon black, which is one of the most common ingredients in tattoo inks, appears to break down readily into nanoparticles and end up in the lymph nodes, the study found. The team also looked at titanium dioxide (TiO2), which is a common ingredient in a white pigment usually combined with other colors to create certain shades. This type of ink does not appear to break down into particles as small as those found with carbon black, but some larger particles of TiO2 were still detected in the cadavers' lymph nodes, the study said.
Disturbingly, Schreiver and her colleagues found that some potentially toxic heavy metals originating in tattoo ink also made their way to the lymph nodes. The scientists detected particles of cobalt, nickel and chromium, which are sometimes added to organic tattoo pigment as preservatives, at the lymph nodes.
"These are not things you want to have permanently deposited in your body," Schreiver said.
Is it harmful?
Other research has shown that tattoo pigment may land elsewhere in the body. For a May 2017 study published in the journal Dermatology, researchers tattooed the backs of mice with black and red ink.
About a year later, the team found ink pigment in the mice's lymph nodes, as was found in human studies, but also within liver cells.
"It was a quite interesting and very surprising finding," said Mitra Sepehri, lead author of the research in mice and an M.D./Ph.D. candidate at the Wound Healing Centre of Bispebjerg University Hospital in Copenhagen, Denmark. "To reach the liver cells, the pigment has to go through the blood to reach the liver. So, we have shown that tattoo pigment can spread through the mouse's blood system as well as through the lymphatic system."
The ink pigment was detected inside special cells in the liver that remove toxic substances, called Kupffer cells. These cells appeared to be in the process of "eating" the pigment particles, Sepehri said. Of course, mice aren't humans, and, as Sepehri pointed out, the study did not confirm that tattooed humans can end up with pigment in their livers. Plus, she added, since mouse skin is thinner than human skin, tattoo ink may be more likely to be deposited more deeply in mice and more likely to enter the bloodstream.
"Even if we find out maybe in five or 10 years that tattoo ink can be deposited in the liver in human beings, we still don't know if it's harmful," Sepehri said. "It may pose no risk"
It's also not known if it's harmful for tattoo pigment particles to accumulate in the lymph nodes. So far, evidence suggests such deposits may cause enlargement of the lymph nodes and some blood clotting. But long-term studies in humans are needed to definitively link tattoo ink in lymph nodes to any harmful effect.
The ingredients within tattoo ink itself also remain largely unknown and under-regulated. A study from Denmark in 2011 found that 10 percent of unopened tattoo ink bottles tested were contaminated with bacteria. And a2012 Danish Environmental Protection Agencystudyrevealed that 1 in 5 tattoo inkscontained carcinogenic chemicals.
Schreiver said she and her team hope to start raising the curtain on tattoo ink ingredients. They next plan to investigate inks associated with tattoo-related skin reactions and infections by analyzing skin biopsies of human patients. For example, it's commonly known that red tattoo ink is often associated with nasty skin reactions. But not all red inks are the same.
"As a chemist, describing a pigment as 'red' means nothing to me," Schreiver said. "We need to analyze the chemistry."
Tattoo ink manufacturing in the United States is overseen by the U.S. Food and Drug Administration (FDA), but as a cosmetic. As the FDA states, "because of other competing public health priorities and a previous lack of evidence of safety problems specifically associated with these pigments, FDA traditionally has not exercisedregulatory authority for color additives on the pigments used in tattoo inks."
Ortiz said this needs to change. She works with the U.C. San Diego Clean Slate Tattoo Removal Program, which provides free care to former gang members who wish to erase their gang-associated tattoos to make it easier to enter the job market or the military. She said she sees many tattoo-related problems that can flare up again during tattoo removal.
"People have tattooed their bodies for thousands of years. Clearly, they're not going to stop," Ortiz said. "So, we need more testing on both the tattooing process and the ink to know potential reactions in the skin so we can optimize the safety of tattoos."
Originally published on Live Science.
Amanda Onion writes about health science advances and other topics at Live Science. Onion has covered science news for ABCNews.com, Time.com and Discovery News, among other publications. A graduate of Dartmouth College and the Columbia School of Journalism, she's a mother, a runner, a skier and proud tree-hugger based in Brooklyn, New York.
The body clears some of the ink away by way of special repair cells called macrophages. The macrophages carry the ink to the closest lymph nodes. Your body can't break these particles down, so they become stuck. A side effect of this is that the lymph nodes can change color to match the color of your tattoo.Why are tattoos permanent if the dyes are injected into the dermis? ›
The reason tattoo ink stays in skin forever has to do with the immune system. When you get a tattoo, the ink flows down the tattooing needle into the middle layer of your skin, called the dermis. That creates a wound, which your body tries to heal by sending macrophages (a type of white blood cell) to the area.What happens in the skin that allows ink to remain and become permanent? ›
The dermal cells remain in place until they die, and when they have completed their life span, they are absorbed by younger cells. This means that the ink travels from one generation of cells to the next, and so the tattoo remains in place.What happens if a tattoo needle hits a vein? ›
“Tattoos involve applying pressure on your skin with a needle, which can rupture the vein, making it bleed into the surrounding tissue and cause an infection,” she says. If you have varicose veins, Chimento goes on to explain, this could make things worse and result in veins that protrude even further.Can tattoo ink affect your brain? ›
Research published in The British Journal of Dermatology found that the nanoparticles in tattoo ink are so small they can penetrate through the skin layers and into the bloodstream. These particles have potential toxic effects in the brain, cause nerve damage and may even be carcinogenic.Why does a tattoo stay permanently in the skin? ›
French researchers say they have found the answer, and it's a little bit surprising. They found that immune system cells called macrophages eat the ink, and then pass it to their replacements when they die. So the tattoo ink doesn't stain skin cells, as many people had believed.What makes a tattoo permanent? ›
And because the ink is a foreign invader, the macrophage cells gobble it up to try to get rid of it. But instead, those macrophage cells with bellies full of ink get stuck in the gel-like matrix of the dermis. And they stay there pretty much forever, which is why the tattoo stays visible and permanent.Why can't you donate blood after getting a tattoo? ›
The American Red Cross require a 12-month waiting period after receiving a tattoo in an unregulated facility before a person can donate blood. This is due to the risk of hepatitis. Hepatitis is a type of liver inflammation.What happens when ink goes in your skin? ›
In fact, mainstream permanent markers contain ingredients that are considered poisonous, such as resin, xylene, and toluene. When these markers come into contact with your skin, mild irritation can occur. Symptoms include redness, swelling, and itchiness.What happens to your skin after a tattoo? ›
Peeling usually occurs a few days after getting the tattoo, as the skin begins to heal and regenerate itself . The regeneration process involves the skin removing dead and damaged cells. As the skin exfoliates itself, a layer of dead skin cells and ink pigment peels off, allowing new cells to grow.
If ink only reaches the epidermis (the first layer of skin), the tattoo will not be permanent, as this layer of skin is continually shedding and replacing itself. Once pigment is placed in the skin, the body reacts by causing the area appear red, swell, and release blood plasma.Can a person with permanent tattoos donate blood? ›
If you have recently had a tattoo or body piercing you cannot donate for 6 months from the date of the procedure. If the body piercing was performed by a registered health professional and any inflammation has settled completely, you can donate blood after 12 hours.Can you donate blood with tattoos? ›
Yes, you can donate blood if you have tattoos
If you got a tattoo in the last three months, it is completely healed, and was applied by a state-regulated facility, which uses sterile needles and fresh ink—and you meet all donor eligibility requirements—you can donate blood!
Because the ink is so deep in the skin, as a result, people can develop serious tattoo infections and skin irritations. There is also a chance one would experience a tattoo blowout since the ink moves freely in the fat layer.What does the Bible say about tattoos? ›
But in the ancient Middle East, the writers of the Hebrew Bible forbade tattooing. Per Leviticus 19:28, “You shall not make gashes in your flesh for the dead, or incise any marks on yourselves.” Historically, scholars have often understood this as a warning against pagan practices of mourning.Do tattoos affect your kidneys? ›
Toxins in some tattoo inks may enter the kidneys, lungs or lymph nodes through the circulatory system, according to Michele Van Vranken, a physician at Teenage Medical Service in Minneapolis, Minn.Do tattoos affect your organs? ›
Tattoo ink may get accumulated in the liver and kidneys over a prolonged period of time but as such does not directly affect the liver. Indirectly, tattoos may cause severe liver damage due to hepatitis infection.Can tattoo ink infect your blood? ›
Because the cells cannot break down the particles, they become lodged there. The side effect is that the lymph nodes take on the same color as your tattoo. There is also some evidence to suggest that tattoo ink particles can travel through the blood and become lodged in the liver.Can you get blood poisoning from a tattoo? ›
Tattoos and body piercings provide an opening in the skin that may allow germs to enter your body and cause infections. These infections could cause sepsis. It is for this reason that anyone who receives a tattoo or piercing must take special care to reduce the risk of contracting an infection.Can you get poisoning from tattoo ink? ›
Thus, the likelihood that you'll get ink poisoning by ingesting ink from a pen or getting some on your skin or in your eye is slight. The likelihood of getting poisoned by tattoo ink has more to do with the safety practices and cleanliness of the tattoo artist and shop than the ink itself.
If the equipment used to create your tattoo is contaminated with infected blood, you can contract various bloodborne diseases — including methicillin-resistant Staphylococcus aureus (MRSA), hepatitis B and hepatitis C.Does tattoo ink affect your immune system? ›
Innate immune responses involve general reactions to foreign material. So getting a new tattoo triggers your immune system to send white blood cells called macrophages to eat invaders and sacrifice themselves to protect against infection.Is tattoo ink cancerous? ›
We are not aware of a reported cancer case directly attributable to tattooing. However, evidence does show that some tattoo inks contain carcinogens (cancer-causing substances) – chemicals that have been classified as known or possible carcinogens by the WHO's International Agency for Research on Cancer.Why do I feel sick after tattoo? ›
Don't panic. This “tattoo flu” is pretty common and should fade into memory in a few days (unlike your new tattoo). Your body's immune system is making you feel wiped out while it attacks potential threats to your bod. Be on the lookout for a mild fever, chills, fatigue, and some tummy discomfort.Can tattoos damage organs? ›
Tattoo ink may get accumulated in the liver and kidneys over a prolonged period of time but as such does not directly affect the liver. Indirectly, tattoos may cause severe liver damage due to hepatitis infection.How long is your blood contaminated after a tattoo? ›
You may not be able to donate if your ink is less than 3 months old. Giving blood after recently getting a tattoo can be dangerous. Though uncommon, an unclean tattoo needle can carry a number of bloodborne viruses, such as: hepatitis B.What are the early warning signs of sepsis? ›
- confusion or disorientation,
- shortness of breath,
- high heart rate,
- fever, or shivering, or feeling very cold,
- extreme pain or discomfort, and.
- clammy or sweaty skin.
When it comes to cancer, black ink can be especially dangerous because it contains a very high level of benzo(a)pyrene. Benzo(a)pyrene is currently listed as a carcinogen by the International Agency for Research on Cancer (IARC).What Stds can you get from a tattoo? ›
Results: There is strong evidence for the transmission of hepatitis B virus (HBV) infection, hepatitis C virus (HCV) infection, and syphilis by tattooing. Tattooing may also transmit the human immunodeficiency virus (HIV), although convincing evidence is still lacking.What does the Bible say about tattoos? ›
But in the ancient Middle East, the writers of the Hebrew Bible forbade tattooing. Per Leviticus 19:28, “You shall not make gashes in your flesh for the dead, or incise any marks on yourselves.” Historically, scholars have often understood this as a warning against pagan practices of mourning.
Tattoos reduce stress
Multiple tattoos were found to reduce cortisol levels, improving the immune system benefits of tattoos, but also helping with stress reduction. High levels of cortisol are associated with many of the physical and mental detriments of stress: Migraines/headaches. Increased weight gain.