Given the attention now being paid specifically to its role in hair colouring, you’d be forgiven for thinking that this was PPD’s only application in the cosmetics world. In fact, PPD can exist in places you may not expect.
Black Henna Tattoos
Perhaps the most insidious is in so-called ‘black henna’ tattoos. ‘Black henna’ (sometimes called ‘piko’ or ‘kahli mendi’) is usually a paste that has had PPD added to it, often in quantities much higher than is permitted by law in hair dye. In many cases, there’s no actual henna in the mixture at all. ‘Black henna’ tattoos are often offered at festivals, on beaches or in other holiday destinations but should absolutely be avoided wherever encountered, as they’re unregulated and potentially extremely dangerous. Because of the high concentration of PPD being applied directly to the skin in so-called ‘black henna’ (there’s actually no such thing - real henna is orange-brown), they can readily cause chemical burns to the skin or trigger a severe reaction in anyone with a PPD allergy. In fact the application of a black henna tattoo is often the incident that ‘activates’ the immune system against PPD creating a new allergy in a sufferer for the first time.
It’s important to note that conventional tattoos done with modern inks do not contain PPD but, as with any cosmetic procedure, it’s best to check first to be confident that nothing is being introduced onto or into your body that it’s unable to tolerate. It is common for tattoo artists to refuse to work on any client with a history of severe allergy or anaphylaxis.
Brow and Lash Tinting
Perhaps a more obvious use of PPD and PTD in the salon is in eyelash and eyebrow tinting. As these treatments use products which generally equate to a semi-permanent hair dye, in most cases you’ll find a comparable concentration of PPD and PTD in these products, and so the same precautions should be taken beforehand.
Despite persistent rumours to the contrary, the use of PPD in makeup is illegal. It is not used in black eyeliner, mascara, brow pencil or any other cosmetic item.
Just a suggestion because I very much like the way you described the role of the immune system in the other file