I have come to this topic in a most round about manner. While listening to a webinar on kidney health, it was mentioned that tattoos may contribute to heavy metal burden within the human body. I needed to know more and I think you do too!
There is more to think about when you consider a tattoo than what the tattoo will be and where it will be located. While it has long been known that the inks, when injected into the skin may cause allergic reactions, chronic skin rashes, infection and inflammation from sun exposure, scientists are unsure whether the chemicals used in tattoo ink can cause long term health effects.
Some pigments are industrial grade colours that are "suitable for printers' ink or automobile paint,” according to an FDA fact sheet. Among the ingredients used in tattoo inks are a varied list of heavy metals including: cadmium, chromium, copper, and lead (some of which are neurotoxic), as well as phalates (plasticizers and known endocrine disruptors). Black tattoo ink may also contain benzo(a)pyrene, which is a polycyclic aromatic hydrocarbon (PAHs), and known carcinogen.
Tattoo ink is not approved by the FDA so there is no regulation of ingredients and what happens to the ink as the tattoo breaks down is largely unknown. It is speculated that exposure to sunlight or laser removal may cause the inks to break down and migrate to other parts of the body. Some of these end products may migrate to lymph nodes but “whether the migration of tattoo ink has health consequences or not is still unknown,” according to a 2009 FDA consumer update. The state of California requires warnings whenever people are exposed to chemicals linked to cancer, birth defects or other reproductive harm. This warning is included in the release forms that people sign before getting tattooed in California.
So, in the end, not only do you need to decide on the design of your tattoo, its location, but you must also decide whether a tattoo is right for you based on the limited information we have regarding the inks used.