Does Hair Dye Use Increase the Risk of Breast Cancer? A Population-Based Case-Control Study of Finnish Women

Abstract

Our results suggest that use of hair dyes is associated with breast cancer incidence. The impact on public health may be substantial due to vast popularity of hair coloring in modern societies. It should be noted that regardless of all efforts, a possibility of bias cannot definitively be ruled out and use of a prospective design is warranted. Based on the present results, it may be concluded however that safety of hair dyes in relation to breast cancer cannot yet be fully acknowledged and lack of external safety assessment within the cosmetics industry is of major concern.