I'm doing a little research to see what tattoo ink is made of, and if it is a good idea to get a new tattoo. (It will still be a long while before I do it, but it never hurts to learn a little).
Truth be told, there is not much research out there about tattoo ink safety. The FDA is supposed to monitor these things, but apparently has slacked on this task. That's probably for the best, since I'm not sure I would trust their decision anyway.
The consensus seems to be, "No one exactly knows if the ink is bad for the body, or what it does to your system." If this was a food item, I would definitely walk away. Adding something that we "created" and are unsure of to my system is usually a "no-go."
That being said, tattoos are so cool. Will I suffer for my vanity? Well, I already have one, and I'm no more screwed up than I was when I got it. I did find some information with a breakdown of the different color inks (which aren't actually "ink") and their typical ingredients. The tattoo I have on my left arm is made of black and green ink. Black is typically made from the charred remains of burnt animal bones or kerosene, or magnetite crystals, or powdered jet. Green is often made from copper, but can also come from many other sources including malachite, and some iron based chemicals. They are considered safe.
I have convinced myself that the tattoo I already have is made of charcoal, magnetite, copper, and malachite. Those substances sound pretty cool, magical. I can live with that.
Interestingly, the article mentions red as being the most likely pigment to be dangerous. Also, yellow is a problem simply due to how much pigment they must use just to get a decent value on the color.
So, the question remains, is the potential risk of having these materials inserted into your skin outweighed by the power that the symbol brings to the wearer?
I suppose I can always just get a clever tan.
(that's an insightful artist. look at this...)