Hydrogen Peroxide and Monoethanolamine Are the Key Causative Ingredients for Hair Dye-Induced Dermatitis and Hair Loss

The study from April 2012 focused on identifying the ingredients in hair dye that cause dermatitis and hair loss. Using female C57BL/6 mice, the researchers applied commercially available hair dyes and ingredient combinations to the mice's skin. They discovered that the combination of hydrogen peroxide (H₂O₂) and monoethanolamine (MEA) was responsible for inducing hair loss and dermatitis. Histological examinations indicated that oxidative stress was the mechanism behind these effects. Additionally, H₂O₂ and MEA were found to cause oxidative stress and cytotoxicity in human keratinocytes. The study concluded that H₂O₂ and MEA are the primary ingredients in hair dye that lead to dermatitis and hair loss.