Widely used products by many cultures and civilizations. Some of their components can be absorbed and reach the mother's plasma and the breast milk. Natural components (lower risk) are: Henna, Saffron, Chamomile and nut among others. Synthetic components are: aniline and other benzene derivatives, heavy metals like lead). In last decade, a bulky amount of products in use have been withdrawn from the market since they were considered to be toxic for the organism. Controversy still exist on the safety of existing products, while some authorities consider them to be safe, a study dated on 2013 has linked them to the appearance of childhood leukemia when used during pregnancy or breastfeeding. It is recommended a limited use, to follow advice appearing with the product, a shower after dye to keep clean the breast area and wearing short hair to minimize absorption of potentially toxic products. Mothers working at hair dressing facilities should observed all preventive measures (wearing gloves, working-time restriction, etc)