Hair dye contacts the skin, and needs to be heated during the hair dyeing process, so that benzene series organic substances enter capillaries through the scalp, and then reach the bone marrow with blood circulation, and repeatedly act on hematopoietic stem cells for a long time, leading to malignant transformation of hematopoietic stem cells and leukemia. One of the reasons why hair dyes can cause skin allergies, leukemia and other diseases is that hair dyes contain a chemical called p-phenylenediamine.

Hair dyeing has become people's fashion choice. According to a survey conducted by CCTV International, among more than 2,600 respondents, more than 90% have dyed their hair, and about half of them started dyeing their hair before the age of 30. 2 1 century, China will enter an aging society. With the increase of silver-haired people, the market demand for hair dyes will increase day by day.

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Harm of hair dye

Experts suggest that you should not dye your hair more than twice a year. Patients with hypertension, heart disease and asthma should not dye their hair. In addition, couples who are ready to give birth, pregnant women and lactating women are not suitable for dyeing their hair.

Long-term use of hair dye is harmful to health. American experts examined 160 popular hair dyes, and found that 150 of them had carcinogenic effects. For example, in oxidized hair dyes, there is a substance called 2-4 amino anisole, which is most likely to accumulate in the human body and promote cell proliferation. In general, if the hair dye is used for 10 years, human skin can cause cancer as long as it absorbs 1% of this substance.

In addition, the use of hair dye will make the immune function of human body disorder, which will lead to lupus erythematosus. Other hair dyes can cause allergic dermatitis and allergic conjunctivitis. Therefore, scientists warn people that hair dyes should be used with caution.

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