AHR and breast cancer: Xenobiotics such as activators of the aryl hydrocarbon receptor (AHR), dioxin, phthalates, polychlorinated biphenyls (PCB), PAHs, bisphenol A (BPA), arsenic etc. prevalent in the environment, dietary items, soil, water, and other consumable products, are likely to contribute to the epigenetic dysregulation of oncogenes and tumor suppressor genes in breast cancer.