Скачать или смотреть FOX28 Special Report: Henna Tattoo Dangers

COLUMBUS (Dawn Faugl) -- Some people who've gotten temporary henna tattoos have found the ink is leaving frightening scars behind.

The problem seems to come from what's known as "black henna." It's not a natural ink.

Dermatologist Matthew Zirwas told FOX28 over the last 10 years, there's been an increase of allergic reactions to the black henna.

"It can be anywhere from a little bit of a rash, no big deal, to this really severe, almost like a second or third-degree burn that will leave this permanent scar," he said.

Zirwas says the chemical in black henna that can cause damage, known as PPD, is the same active ingredient in hair dyes.

The FDA says vendors add the extra ingredients to make the henna tattoo art darker and longer lasting, but it can also be harmful. Last year, the FDA put out a warning to consumers about the product.

Natural henna artists say black henna has stained their industry, and there are several tell tale signs to know if you're getting chemical-based henna. "If they tell you to wash it off in 20 minutes, you know it's chemical based," henna artist Deborah Brommer said.