- Tattoo ink contains known carcinogens, and can be transported around the body and end up in the lymph nodes.
- However, there is little research into whether or not having a tattoo raises a person’s risk of cancer.
- Researchers from Lund University Sweden used national registries to identify cases of lymphoma and analyze whether they could be linked to tattoos.
- They found a 21% increased risk of lymphoma in people who had tattoos, compared to those who did not.
- Researchers are now looking at whether tattoos can raise the risk of different kinds of cancer.
Tattoos were associated with a 21% increased risk of lymphoma, a type of blood cancer, in an observational study of a Swedish cohort.
Researchers from Lund University, Sweden analyzed the Swedish National Cancer Register, and found that the size of the tattoo had little effect on the risk of cancer. The results are published in eClinical Medicine.
While researchers were already aware of the potentially carcinogenic properties of some tattoo inks, the authors of this study said the impact they had on cancer risk was not, prompting them to undertake the current research.
First author Christel Nielsen, PhD, an associate professor at the University of Lund, in Sweden, explained to Medical News Today:
“There has been quite a lot of focus on the chemical content of tattoo ink during the last 10 years, particularly in Europe. Tattoo ink often contains chemicals that are known to cause cancer in other contexts, for example in occupationally exposed workers. We also know that the ink is transported away from the skin by the immune system, as the body tries to remove the ink particles that it perceives as something foreign that should not be there. It has been shown that this process moves the pigment to the lymph nodes, and that it is permanently stored there.”
“We wanted to connect the dots and understand how our health is affected by permanent storage of potentially toxic chemicals within the immune system,” she told us.
Researchers identified cases of lymphoma in the Swedish National Cancer Register, a centralized database of cancer cases in the country. In order to include people most likely to have a tattoo they restricted the ages of patients they were interested in identifying to 20–60 years old, when they were diagnosed with lymphoma, between 2007 and 2017.
They then contacted affected individuals and controls — three per affected individual — to ask them to opt in to the study, and ended up with a study group of 1,398 people with lymphoma and 4,193 people without lymphoma.
They discovered that 21% of the people with lymphoma had a tattoo, and 18% of those without lymphoma had a tattoo.
The risk was 81% higher for people with tattoos than people without tattoos, in the 2 years after receiving a tattoo, researchers found. This risk dropped between years 3–10 post-tattooing and then increased to a 19% higher risk after 11 years.
Overall, participants with tattoos had a 21% higher risk of lymphoma compared to controls. The size of the tattoo did not impact the risk of lymphoma.
The two lymphomas which individuals with tattoos were at most increased risk of developing compared to those without tattoos were diffuse large B-cell lymphoma and follicular lymphoma.
The authors of the current study did not investigate why the increased risk occurred with tattooing, though they did adjust their analysis for potentially confounding factors, such as educational attainment, income, smoking, or marital status, to minimize the potential effect of socioeconomic status and lifestyle on the results.
MNT asked Wael Harb, MD, board-certified hematologist and medical oncologist at MemorialCare Cancer Institute at Orange Coast and Saddleback Medical Centers in Orange County, CA, not involved in this research, whether the differences observed between people with and without tattoos could, in fact, be due to lifestyle factors.
According to him:
“The study adjusted for several lifestyle factors, including smoking and socioeconomic status, in its analysis. While tattoos themselves were found to be a risk factor for lymphoma, the lifestyle factors associated with individuals who get tattoos (e.g., smoking, substance use) could also contribute to the increased risk.“
Harb cautioned that “[t]he study’s findings indicate the need for further research to disentangle the effects of tattoos from related lifestyle factors and to understand better the role of lifestyle in the observed associations.”
Rachel Orritt, PhD, health information manager at Cancer Research UK, also not involved in the study, said “[t]here isn’t enough evidence to say that tattoos increase people’s cancer risk, and more research is needed.“
She agreed with Harb that “[i]n this study in particular, other reasons could explain why people with tattoos had a higher risk of malignant lymphoma.“
“This is a difficult area to study, because there are lots of different possible ingredients in tattoo ink, making it tricky to understand the effects,“ noted Orritt.
“If people are concerned about their cancer risk, there are proven steps they can take to reduce it. These include not smoking, eating a healthy, balanced diet, and cutting down on alcohol,” she advised.
Tattooing exposes people not only to the ink in the tattoo but also the risks associated with needle use.
There is a risk that hepatitis C can be passed on via tattooing needles that are not properly sterilized, and links have been made between hepatitis C and increased risk of non-Hodgkin lymphoma.
Insofar as blood cancer risk is concerned, Nielsen told MNT that a few viruses were a possible cause of lymphoma but, she opined, ”Swedish tattooists are very well educated in terms of safety and hygiene, so I don’t think that can explain our results.”
The study authors were keen to point out that tattoo popularity had increased in the early 2000s. In fact, Nielsen has even publicly stated that most of her research team has tattoos.
This increased popularity meant that about 20% of Europeans had tattoos and up to 30% of Americans had tattoos. The fact that many people got tattoos at a young age meant that people were exposed to the ink in them over a lifetime. However, the impact they could have on health had not been adequately scrutinized.
Nielsen said:
“It is important to keep in mind that lymphoma is a very rare disease, and that the 21% increase relates to a baseline risk that is very low. However, I would like to highlight that tattooed individuals should be aware that tattoos might have adverse health effects, and that you should seek medical care if you experience any symptoms that you think may be tattoo-related.“
“We have done parallel studies on two types of skin cancers (malignant melanoma and squamous cell carcinoma) that will be published shortly. We are also about to start new studies to investigate if tattoos also increase the risk of other diseases of the immune system, such as thyroid disease and rheumatoid arthritis,” Nielsen also told us.
