IT was supposed to be a harmless holiday souvenir but a temporary tattoo could leave little Jess Errington with permanent health problems.

The five-year-old was enjoying a winter escape in Bali with his parents this month and begged to be allowed to have two henna dragon tattoos, the Gold Coast Bulletin reported.

His "ink" had almost faded by the time he returned to school this week but in its place are 2mm raised, dragon-shaped welts.

His horrified parents, Paul Errington and Kirsty Dutton, have since discovered local artists had added a toxic chemical, para-phenylenediamine (PPD), to the usual vegetable dye mix to darken the tattoo.

In Australia the chemical which is used in strong hair dye, is known for causing allergic reactions with lifelong effects.

These can include skin problems and a permanent allergy to anything containing PPD, including black clothing, dark hair dye and some cosmetics.

"We just feel terrible - it was supposed to be a totally innocent holiday souvenir," Mr Errington said.

"I've got tattoos and every boy wants to be like their daddy, so when he saw all the kids getting them done on the beach in Bali I gave in, thinking it was harmless."

To treat the chemical burn the family have to gently apply a steroid cream to bring down the welts.

"Luckily he's not in any pain but we're worried he could be permanently scarred," Mr Errington said.

Gold Coast dermatologist Dr Michael Freeman said he saw about one serious case a year and with two per cent of people had complications from an allergic reaction. Of those affected, at least five per cent were severe.

Read more at the Gold Coast Bulletin.

Originally published as Five-year-old boy's tattoo nightmare