THE British Skin Foundation is issuing a warning this summer over so-called black henna temporary tattoos (BHTTs) after research among dermatologists reveals they are seeing an increase in reactions at their clinics.

Parents hoping to treat their children to a temporary tattoo on holiday or at the funfair, along with party-goers at festivals may not realise the dangers of BHTT.

The majority of BHTT are not based on henna at all, but a substance called para-phenylenediamine (PPD) which is found in hair dyes, says the foundation.

PPD is allowed for use in hair dye, but its use for skin contact products such as temporary tattoos is illegal in the European Union.

When PPD is used on the skin in this way it can cause blistering, painful skin burns and may even lead to scarring. It can also leave the person with a lifelong sensitivity to PPD, which increases the risk of a severe allergic reaction when using hair dye in the future.

The foundation's survey found:

• 4 out of 10 dermatologists asked had seen patients with skin reactions to BHTTs.

• 1 in 20 dermatologists approached said that over 80% of the BHTT reactions they had seen were in children aged under 16.

• Dermatologists asked confirmed that around half of the patients got a BHTT outside of the EU, where the legal status of PPD is not always clear; however the other half got a BHTT within the EU, with 27% of these in the UK.

• About two-thirds of dermatologists approached have seen an increase in patients with reactions to hair dyes, many of whom have previously had a BHTT.

Dr Anjali Mahto, consultant dermatologist and British Skin Foundation spokesman, said: “Black henna is well known to cause skin reactions and should be treated with caution, particularly in children.”

And Dr Christopher Flower, director-general of the Cosmetic, Toiletry & Perfumery Association, said: “The message is clear: having a ‘black henna’ temporary tattoo presents a significant risk of a very nasty adverse reaction to the tattoo itself.

"It also increases the risk of either not being able to use most hair dyes in the future or having a bad reaction to them if the warnings are ignored.

"This summer, parents will want to keep their children safe, by steering clear of so-called ‘black henna’ temporary tattoos.”