I’m going to keep this short. “Black henna”, also sometimes referred to as “kali mehndi” is not henna at all, but a toxic chemical, p-paraphenylenediamine (PPD for short) mainly used as a hair dye. When used as a hair dye, colorists are instructed to wear gloves to avoid getting it on their skin, avoid touching it to the client’s scalp, and totally off limits for pregnant women. This alone should tell you something.
Do you think you are safe because you are getting a henna design from an “ethnic” or “traditional” artist? Think again. Many places in India (as well as the rest of South Asia), the Persian Gulf, and the African continent are using “black henna” and claiming it is traditional and natural. It’s not natural, it’s not traditional, and it’s not safe. When I was traveling in India, I met a cute 13 year old girl who was doing black henna at the beach. She only spoke a few words of English, but she knew the word “allergy”. In fact she had no knowledge whatsoever of how natural henna worked. When I did a design for her in natural henna, she washed the paste off after 20 minutes and wondered why the stain was orange. Don’t assume that “traditional” artists are educated just because henna is “part of their culture”. Just because someone is French doesn’t mean they know how to make a great baguette or how to prepare a bouillabaisse. Indians are not born knowing how to do henna – the knowledge must be acquired. In many parts of Africa, “black henna” is now the norm, but this doesn’t make it safe!
Additionally, “black henna” is also being offered in tourist destinations such as Mexico, Costa Rica, Brazil, and other beach or “Spring Break” locations, and shockingly, even in the USA!
Always ask your artist what the ingredients in their henna paste consist of. Ingredients should all be recognizable – henna/mehndi leaf powder, water or lemon juice, essential oils (usually tea tree or lavender), and sugar. Terms to watch out for are “mehndi oil”, “black clove oil”, sodium picramate, metallic salts, PPD, or “henna stone”. Vague terms like “mehndi oil” often signify the addition of toxic solvents like benzene. If the mixture smells like ammonia or chemicals, this is another sign the artist could be using unsafe ingredients. Real henna needs to be left on the skin for several hours or more in order to give a great color, and the stain starts out orange and oxidizes to a reddish brown tone over 48 hours. Occasionally, on the palms and soles of the feet, henna can reach a nearly black color, but shining a light on it, you will see it is actually a very rich brown or red. Sometimes, repeated applications of the henna can also achieve a similar effect, but once again, the the stain is not instant and requires many hours to achieve.
Ok, so you think just this once isn’t going to hurt you? What if your bridal mehndi turned out looking like the image below? What if you then had a lifelong allergy to black dyes, including hair dye, printer ink, or even black socks or underwear?