Study cannot demonstrate causality between hair dye and straightener use and breast cancer but in this case, no one needs them to survive. Let the science continue to evaluate these products.

Medical Mythbusting Commentary for December 6, 2019

Source:
Some Hair Dyes and Chemical Straighteners May Be Linked to Breast Cancer

Reference:
Hair dye and chemical straightener use and breast cancer risk in a large US population of black and white women