Whether it is a butterfly on your ankle or your football team鈥檚 logo across your back, tattoos have long been seen as a way of expressing individuality, as well as sometimes having cultural significance. Yet research is just starting to scratch the surface of their potential health effects.
Tattoo pigments are made up of numerous chemicals. In the European Union, the Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH) legislation has set concentration limits for around 4000 compounds in such pigments, mostly due to cancer concerns. But some of these are legal at higher levels in other parts of Europe and the US.
鈥淭his is a difficult area to study because there are lots of different possible ingredients in tattoo ink,鈥� says at Cancer Research UK.
Advertisement
However, scientists have tried to do so recently. In October last year, an of green and blue inks sold across Europe found that nine out of 10 weren鈥檛 compliant with REACH and four contained banned compounds. 鈥溾�楢re tattoos safe?鈥� is something I get asked a lot, but the problem we have is if we don鈥檛 know what鈥檚 going into the tattoo, we can鈥檛 begin to answer that question,鈥� says team member at Binghamton University in New York.
These pigments also don鈥檛 just stay near the skin鈥檚 surface. 鈥淲hat happens is that the immune system gets triggered, as it recognises something foreign,鈥� says at Lund University in Sweden. Immune cells called macrophages then pick up the pigments and carry them , perhaps to try to clear them from the body. Doctors even with advanced cancer when they thought his black lymph nodes were a sign of the condition.
鈥淲e know that ink makes its way to the lymph nodes and we know that there are potentially toxic chemicals in the ink,鈥� says Nielsen. To understand the possible effects of this, she and her team just under 1400 people, aged between 20 and 60, in Sweden who had been diagnosed with lymphoma 鈥� cancer of the lymphatic system, including the lymph nodes 鈥� within the past decade. They compared this group with nearly 4200 cancer-free individuals who were matched by age, sex and socioeconomic backgrounds.
The results, also published in 2024, show that the people with a tattoo were 20 per cent more likely to develop any type of lymphoma than those without one.
Perhaps surprisingly, individuals who opted for laser removal of a tattoo were almost three times more at risk of the condition than their untattooed counterparts. 鈥淭he laser fragments the [tattoo] molecules, making them smaller so that they can be removed via the lymphatic system, but that process also makes the chemicals more reactive and potentially more toxic,鈥� says Nielsen.
The researchers didn鈥檛 find evidence that coloured or uncoloured ink is more linked to lymphoma, or that the risk accumulates with having multiple tattoos. But Nielsen says the study may not have been large enough to capture such potential associations.
Nevertheless, she stresses that the individual risk is probably low. 鈥淟ymphoma is still a rare disease, with about 300 people diagnosed in Sweden every year out of a population of 10 million,鈥� she says. 鈥淥ur estimates apply on [a] group level, and can[not] and should not be interpreted as individual risks, because we are all different and the risk estimate is somewhat of an average.鈥�
Nielsen鈥檚 results have been supported by a more recent study, in which at the University of Southern Denmark and her colleagues looked at 158 pairs of twins, at least one of whom had been diagnosed with certain cancers, namely lymphoma or skin cancer.
They too found a link between lymphoma and tattoos, but their work suggests that . Having a tattoo that is larger than a typical palm was linked to triple the rate of developing lymphoma and an approximate doubling in the rate of skin cancer, compared with having no tattoos.
But regardless of tattoo size, the rate of skin cancer was still 60 per cent higher among tattooed individuals. 鈥淲e think one of these mechanisms is that [tattooing] causes a chronic immune response, because the immune system is constantly trying to do something to this foreign body, and when the immune system is constantly on alert, it will lead to an increased risk of abnormal cell proliferation,鈥� says Clemmensen. 鈥淲hen you experience that, we know it can give an increased risk of cancer.鈥�
While the scientists are concerned, they also stressed that the link between tattoos and cancer is far from cut and dried. 鈥淢ore studies are needed before we can establish a causal link,鈥� says Nielsen, who has several tattoos herself. These may include cell or animal research and larger observational studies in multiple countries.
鈥淭here isn鈥檛 enough evidence to say that tattoos increase people鈥檚 cancer risk; more research is needed,鈥� says Orritt.
In the meantime, Clemmenson doesn鈥檛 think people should be unduly put off getting inked. 鈥淲hat I would say to someone with a tattoo or perhaps considering getting a tattoo, is that it鈥檚 not something they should be overly concerned about yet,鈥� she says.
