Shampoo is a hair care product used for cleaning the hair and scalp. It is typically composed of cleansing agents, additives for stability and comfort, conditioning agents, and special care ingredients to treat specific problems such as dandruff and greasy hair
. Shampoos can contain 10–30 ingredients, and they are grouped into various categories based on their functions
. Some shampoos are sulfate-free, which means they do not contain anionic surfactants, and they may contain cationic, amphoteric, and nonionic surfactants to reduce static electricity and optimize the formation of foam and viscosity
. When it comes to the safety of shampoo ingredients, it's important to be aware of potential hazards. Some common cosmetic ingredients, including those found in shampoos, are designed to penetrate the skin and can be absorbed into the body
. For example, coal tar, a known human carcinogen, is found in some specialty shampoos for conditions like dandruff and psoriasis, although its long-term safety has not been demonstrated
. Additionally, formaldehyde, a potent preservative, has been found in some hair straightening products and can release potentially toxic fumes during use
. In conclusion, shampoos contain a variety of ingredients that serve different purposes, from cleansing to conditioning and treating specific hair and scalp issues. It's important for consumers to be aware of the ingredients in their shampoos and to consider potential safety concerns associated with certain ingredients.
