According to Britain’s Daily Mail newspaper, the scientists found that both home hair coloring kits and salon dyes can lead to many health problems. Nearly 400 out of the 456 hair colors ranked in the Skin Deep cosmetics database of the Environmental Working Group contain dangerous toxic ingredients that cause cancer, developmental and reproductive toxicity, immunotoxicity, organ toxicity, and allergies.
Probably the most famous natural hair dye is henna. It has been used since ancient times. Today henna comes with many shades and is absolutely safe.