lead (yellow, green, white)
cadmium (red, orange, yellow)
aluminium (green, violet)
iron (brown, red, black)
ferrocyanide and ferricyanide (yellow, red, green, blue)
Other pigments include antimony, arsenic, and beryllium.
These are all neurological disruptors, and are active at the microgram level. Implanted in large quantities, they may quickly lead to a host of disorders.
If you want to improve your health, you need to minimize your exposure to harmful properties – tattoo removal for this purpose is a smart decision. Learn how to improve your brain health by reading Bodygarage, the solution book for migraine and much more.
Read more about heavy metals and tattoos at Wikipedia.