: Harmful aspects of hair color: Decrease the brightness of hair: Hair color reduces the brightness of hair. There may also be hair loss , split ends, dandruff and rash. Physical Illness: Hair color can cause skin diseases , lung or eye damage. The use of hair color can increase the difficulty of breathing. Hair color chemicals can also cause human cancers , such as leukemia , non-Hodgkin 's lymphoma , bladder cancer , blood cancer, and multiple myeloma. Skin Irritation and Allergies: Hair color causes irritation and allergies on the scalp. Hair color can cause itching , redness , burning and discomfort within a few hours to a day . Hair color should not be used in such discomfort. So you need to do an allergy test before using the color. Hair breakage: When hair is colored, the hair becomes rough and breaks. In addition to split ends, there are problems such as hair falling out through the middle. Gradually the hair becomes thinner. If there is such a problem, there is no other way but to cut the torn hair. Dyed Hair Care: If you have dyed your hair, you need to take care of your hair regularly. Otherwise the hair will become rough and fall out.