Henna is a green powder and smells very earthy (like wet tree bark). Henna powder is created by crushing the dried leaves of a henna plant. Natural henna stains the skin a light orange to a dark mahogany brown and will last anything from one to four weeks. Natural henna will not stain your skin black.
Black henna has to be chemically altered to leave a black stain on your skin. Unethical artists and manufacturers may add chemicals such as PPD (para-phenylenediamine) to get that deep black colour people are demanding. PPD is a potentially harmful chemical and is usually found in hair dyes. Hair dye packages insist that the dye only be left on the scalp for 20-30 minutes, anything longer can be harmful to your hair and or scalp.
Possible side effects, especially in children and those with allergies and sensitive skin,may include itchy skin, rashes, blisters, and nausea. In some cases, more extreme side effects may include permanent scarring, asthma attacks, and skin cancer (if the chemicals enter the bloodstream).
The photograph on the right shows the damage caused by black henna, courtesy of The National Newspaper and the one below courtesy of Dr H Mahdi from Derm Atlas.
Just recently, we were shown a bottle of henna purchased from a store shelf in Ottawa. The ingredients listed an item we hadn't seen before called "Terpinol", but everything else seemed to be fine. We googled the ingredient, and found that terpinol is a derivative of Turpentine. As you may or may not know, Turpentine is an industrial-strength paint thinner. And it is definitely not safe for your body, in fact, it is highly poisonous.
We suggest that you always ask your henna artist about the ingredients in their paste, and if you are in any doubt or have any concerns, don’t get the tattoo.