Hormones and Endocrine-Disrupting Compounds Linked to Breast Cancer

There is broad agreement that exposure over time to natural and synthetic estrogens in the body increases the risk of breast cancer. Hormone replacement therapy (HRT) and hormones in oral contraceptives and some other pharmaceuticals also increase the risk. In fact, steroidal estrogens (the natural chemical forms of estrogen) are classified as known human carcinogens.

Synthetic chemicals that mimic the actions of estrogens are known as xenoestrogens, and are one category of EDCs that increase the risk of breast cancer by interfering with normal hormone function. Evidence indicates that EDCs also may contribute to early puberty, which is itself a risk factor for breast cancer. These compounds are present in many pesticides, fuels, plastics, air pollution, detergents, industrial solvents, tobacco smoke, prescription drugs, food additives, metals and personal care products, including sunscreens. Click on the links below to learn more.

Fact Sheets

Alkylphenols
Bisphenol A (BPA)
DDT/DDE
Diethylstilbestrol (DES)
Dioxins
Hormone replacement therapy (HRT)
Metals
Oral contraceptives
Parabens
Pesticides
Phthalates
Phytoestrogens
Polychlorinated biphenyls (PCBs)
Polycylic aromatic hydrocarbons (PAHs)
Recombinant bovine growth hormone (rBGH/rBST)
Tobacco smoke
Zeranol

For references, see State of the Evidence 2008.