A COUNCIL today warned about the safety of black henna tattoos after tests revealed a Weymouth street trader was found using potentially harmful powder.

A sample from the trader showed a high reading of the substance paraphenylenenediamine (PPD) which can cause scarring and allergic reactions, said Weymouth and Portland Borough Council.

Concern has been raised as more traders have started to use hair dye on the skin to create traditional henna designs, as it leaves a more distinct pattern.

The council said the use of hair dye has resulted in people being exposed to PPD.

The borough's environmental health department said it is now working with the Health and Safety Executive to prevent further use of the potentially harmful substance.

Janet Moore, borough environmental health officer, said: "Following concerns raised by members of the public, samples of dye used by a street trader have been analysed.

"These tests have confirmed that the produce material is actually 94 per cent PPD, not henna at all.

"Since some individuals are known to be sensitive to PPD, the produce tested would seem to be inappropriate for dermal use."

The council advised anyone interested in a hanna tattoo to always ask the trader what is in their product.

Henna is a greeny-brown paste with a heavy smell, but a jet black inky paint with no smell should be avoided, said the authority.

Janet Moore added: "We are aware of cases throughout the country where people have suffered severe adverse reactions and permanent scarring.

"Not everyone exposed to the dye will suffer in this way but people who are hypersensitive or allergic to the dye are susceptible, which can be traumatic for the person affected."

Traders applying henna body art are being advised to carry out safety tests and obtain data sheets from dye manufacturers or suppliers.

On dye considered suitable for skin, traders should carry out a patch test 24 to 48 hours before treatment to detect whether someone is likely to suffer a reaction, the council added.