When you get a tattoo, pigments are injected into the skin with a tattoo needle that has been soaked in tattoo ink. This process involves repeatedly puncturing the skin, which causes the skin to bleed where the needle has been inserted.
The colour pigments accumulate at the boundary of the uppermost layer of skin and cannot be transported away by the body’s own scavenger cells (macrophages). The pigments are deposited in the macrophages, where they remain. During and after tattooing, however, some of the ink is transported away from the skin and is eliminated via the liver or stored in the lymph nodes.
edding is really interested in learning more about this and is currently planning a long-term study on tattoo ink with dermatologists.