A 10-year-old boy has got awful scars after a henna tattoo he had done on his holiday in Turkey went wrong.
Safe henna tattoos
Find out more about henna tattoos here:
What are the different types of henna?
I've got a black henna tattoo
How can I know if the tattoo guy is using safe henna?
Things to look out for when getting a henna tattoo
Actually, there is only one type of henna - pure brown henna. This is pretty harmless to skin and hair. It's unusual to have an allergic reaction to brown henna.
However, there is also something called black henna, which people can have a bad allergic reaction to. Black henna is made by mixing natural brown henna with a chemical dye called PPD (which stands for paraphenylenediamine).
Under European rules, it is illegal to use PPD in black henna.
Black henna is much more likely to cause an allergic reaction, and can leave some people with permanent scarring. Some people have even been killed after having a black henna tattoo. You SHOULD NOT have a black henna tattoo.
Is it itching? If it isn't, then don't worry.
Itchiness only happens when you have an allergic reaction to PPD.
If it is itching or you get a blister on your tattoo then you must go and see a doctor immediately.
When you see the doctor, it's important to tell them that someone painted black hair dye on your skin.
Unfortunately, anyone using the dodgy black henna is probably going to be a bit dodgy themselves and not tell you the truth if you ask them.
If the dye used is jet black and stains the skin really quickly, then it's probably PPD black henna.
Ask how long you should leave it on. If the answer's less than an hour, then they're using PPD. Real henna takes much longer. Most respectable artists will ask you try to keep the paste on overnight.
Ask what colour the tattoo will be when the paste comes off. If the answer is black and the paste is black, then it's PPD henna. Pure henna will leave an orange stain that will go brown, but it will NOT be black when the paste flakes off.
Ask how long the tattoo will last. PPD black henna lasts a week, henna lasts 1-3 weeks and safe black body dyes last less than three days.
Ask what's in the mix. A decent artist will tell you: henna, lemon juice and essential oils. A dodgy one will lie. You should be able to smell the oils or lemon juice in the paste.
If you're still unsure, walk away. There'll always be another chance to get a henna tattoo, so is it worth the risk?