Henna, lawsonia inermis, has ONE translucent dye color, rusty red-orange, based on the lawsone molecule precursors naturally produced in the henna leaf. The commercially available henna hair dyes that come in “colors,” such as black, brunette, chestnut, blonde, and so on, are compound hennas. These products have additives to change the color of henna. The additives may be other plants, toxic metallic salts, chemical dyes, ingredients that have quasi-spiritual claims, and para-phenylenediamine to create a range of colors. These hair dyes often contain little henna, or possibly even no henna whatsoever. Sometimes these compound henna dye additives are harmless, others are dangerous. If the additives and adulterants are not declared, they can cause all sorts of health problems as well as destructive cross-reactions if they come in contact with the chemicals used in oxidative dyes.
The added ingredients in compound hennas are often not listed or the declarations may be fallacious if the countries of origin do not require declarations for cosmetics, or if the manufacturer chooses to obfuscate for profit. If exported to the west; there is no requirement that the additives be discovered and declared. The pre-packaged henna compounds are often termed “natural herbal henna.” This is misleading as these are not “natural” products; they are full of synthetic chemicals. Metallic salts alter and fix color in lieu of higher quality henna. The compounds of henna and metallic salts can react disastrously with synthetic hair dye, seriously damaging hair. The most frequently used material is lead acetate, though silver nitrate, copper, nickel, cobalt, bismuth and iron salts have also been used. Dyes with lead acetate gradually deposit a mixture of lead sulfide and lead oxide on the hair shaft. When you hear that henna has “metal,” “lead,” or “coats the hair,” and “leaves it brittle,” a compound henna dye is being referred to, not pure body art quality henna such as Ancient Sunrise.
Read more: https://www.mehandi.com/v/vspfiles/downloadables/chapt3_compound-henna.pdf
Links to specific topics in this chapter:
Compound henna, rasticks, henna-reng, henna-rasticks, and metallic salts
Henna mislabeling, misinformation and disinformation
Para-phenylenediamine and henna
Walnut, Silver Nitrate, and Para-phenylenediamine as Brunette Hair Dye
