Hair dye contains more than 5,000 chemicals. The list includes some known carcinogens (substances that can cause cancer) like aromatic amines, 3-amino-4-methoxyaniline, 2-nitro-4-aminoaniline and 3-nitro-4-hydroxyaniline.  

These chemicals can disrupt the actions and levels of hormones in your body, affecting cancer risk. In this Q&A, cancer specialist Chirag Shah, MD, explains what we know about hair dye and breast cancer risk. 

Read the full article at health.clevelandclinic.org