A tattoo is an ink design inserted into the skin, commonly via a needle.A variety of pigments and inks are used in modern tattoo, ranging from traditional black to a wide range of colors. Some of the colors used for tattoo pigment may be toxic, raising concerns about extensive color work.
If you are concerned, ask the artist about what pigments he or she is using and whether any adverse reactions to the inks have been noticed. Many tattoos will also require touchup, as exposure to sunlight and water degrades the inks.