The latest version of the World Health Organization’s list of Class I carcinogens is “on the list” of harmful substances that hair dyes can contain, such as formaldehyde, benzene, phenols, etc.
In addition, hairdressers, an occupation that involves long-term exposure to hair dyes, are listed as a Class II carcinogenic risk factor. The hairdresser’s job is to make sure that the hair is in good condition.
How do hair dyes cause leukemia?
It turns out that hair dyes commonly contain p-phenylenediamine, a carcinogenic substance, which enters the capillaries through the scalp after contact with the skin, and then reaches the bone marrow with the blood circulation, where it repeatedly acts on hematopoietic stem cells (the seed cells of hematopoiesis) for a long time, leading to abnormal hematopoiesis and even the development of leukemia.
Nearly 90% of hair dyes contain toxic chemicals such as nitrobenzene and aniline, which are harmful to humans. Therefore, try not to dye your hair if you can.