A review of the role of emerging environmental contaminants in the development of breast cancer in women

The incidence of breast cancer is on a rise worldwide; it is a disease having a complex etiology. Besides genetics, environmental and other lifestyle factors play a role in the development of the disease. There has been a keen interest in studying associations between breast cancer and exposures to emerging environmental chemicals, which mimic estrogens or influence estrogen levels and signaling in the human body. The common consequence of an endocrine disrupting chemical exposure is that it may have an impact on breast cancer etiology by stimulating formation as well as progression of breast cancer. Exposures to selected emerging environmental contaminants such as alkylphenols (APs), bisphenol A (BPA), parabens, perfluoroalkyl substances (PFASs), phthalates, polybrominated diphenyl ethers (PBDEs), synthetic musks and triclosan, and their probable role in breast cancer development are reviewed. Studies evaluated include the experimental in vitro and in vivo studies as well as human population based studies. In vitro and in vivo evidences indicate that a number of emerging environmental contaminants may play a role in the initiation and/or progression of breast cancer. Although exposures have been assessed in some human populations, breast and other cancer risks associated with these exposures are largely unknown. Efforts should be focussed on the evaluation of these environmental exposures in human populations and their interactions with each other and other genetic and lifestyle risk factors