Everyone knows that non-sterile tattoo needles can lead to AIDS and hepatitis. However, according to research by Ronald Petruso, lecturer of chemistry at Delaware Valley College in Doylestown, PA, there are other, overlooked, risks of getting a tattoo.

For the past year and a half, Petruso has been collaborating with Jani Ingram of Northern Arizona University in studying the toxicology of tattoo pigments. As television shows such as "Miami Ink" and "Inked" gain in popularity, Petruso and Ingram wanted to delve into a topic that doesn't get that much press in an industry that that the government doesn't control.

"It's not federally regulated and you don't need a license in order to practice. But it should be because since these pigments are going under the skin, they're being used as drugs," Petruso said.

"The number of people with tattoos is growing and still we don't see much aired in newspapers, broadcast news, or the rest of the media about possible dangers outside of AIDS and hepatitis. We just wanted to look into the situation and see where the research takes us and see if we can make people more vigilant about the risks."

At Northern Arizona, Ingram has found traces of lead in tattoo pigments. Meanwhile, at Delaware Valley, Petruso with the help of two students found carcinogenic substances in a common tattoo pigment.

The shocking detail about this finding was that the carcinogenic pigment was manufactured at Sun Chemical in Cincinnati, with no intended use for tattoos.

"When we told Sun Chemical about our findings they were very concerned about this because this is not what they design their products for. The pigments they make are used by auto manufacturers for making paint," he said.

"The real implication of this finding is that some tattoo pigments are being exchanged under the table. Sun Chemical said that if they found out the source of who's misusing their products, they would go after them and sue them."

"There are so many tattoo parlors out there that you don't have any idea where they're buying their supplies. People come in knowing about hepatitis and AIDS and these days tattoo artists are careful about ensuring that the needles are sterile. But they don't expect to see other problems. They have no idea of the chemicals present in those pigments, and that's the situation that needs to be addressed," Petruso said.