A study has found that common chemicals can interfere with normal breast development https://medicalxpress.com/news/2026-10-common-chemicals-breast.html Environmental chemical mixtures reprogram mammary epithelial development to epigenetic states associated with breast cancer https://www.pnas.org/doi/10.1073/pnas.2613054123 Bisphenol mixtures disrupt normal development: While different chemicals affected tissue development in different ways, the most striking finding involved three common bisphenols: BPA, BPS and BPF. Individually, the chemicals produced relatively few changes in the organoids. But when combined at very low concentrations—comparable to levels detected in human blood and urine—the mixture disrupted normal breast development in organoids from most of the donors