Xenoestrogens and Breast Health
Xenoestrogens consist of several environmental toxins that act similarly to estrogen in the body and can disrupt estrogen metabolism. Xenoestrogens impact breast cancer risk by mimicking endogenous estrogens and interacting with estrogen receptors, thereby influencing estrogen signaling pathways and potentially promoting carcinogenesis. Among xenoestrogens, phthalates and BPA are present everywhere, with research showing that almost everyone has them in their bodies. These estrogen-mimicking chemicals can bind to the estrogen receptors, similarly to the way that estrogen binds and disrupts estrogen pathways and metabolism. Phthalates are used in vinyl, plastics, adhesives, artificial fragrances (laundry detergent, air freshener), personal care products, and more. BPA is also found in plastics, and we are exposed through food and drinks being stored in plastic containers or cans with linings containing BPA. Even the paperboard used in food packaging (especially if it is recycled cardboard) can contain BPA, which is then transferred to the food we eat.
These estrogens have been linked to increased risk of several estrogen-related conditions, including almost 2-fold increase in breast cancer for higher phthalate exposure (estrogen receptor-positive). BPA exposure at low levels is linked to increased breast and prostate cancer. A study by Pastor-Barriuso et al. demonstrated a strong positive association between the total effective xenoestrogen burden in serum and breast cancer risk. The study found that higher levels of xenoestrogens were significantly associated with increased odds of breast cancer, highlighting the importance of evaluating xenoestrogen mixtures rather than single compounds.
Additionally, xenoestrogens can upregulate aromatase activity, leading to increased local estrogen production in breast tissue. Williams and Darbre showed that low-dose environmental endocrine disruptors, including xenoestrogens, increased aromatase activity and estradiol biosynthesis in human breast cells, thereby promoting estrogen-sensitive breast cancer proliferation.
Furthermore, xenoestrogens can disrupt normal estrogen signaling and homeostasis, leading to chronic inflammation and increased breast cancer risk. Maharjan et al. discussed how synthetic xenoestrogens are proinflammatory and carcinogenic, contributing to breast cancer development through their interaction with estrogen signaling pathways.
How to Avoid Xenoestrogens
Plastics
Plastics that contain phthalates and bisphenol A (BPA). Phthalates are plasticizers found in household products like vinyl flooring, lubricating oils, soaps, shampoos, and hair sprays and are frequently incorporated into plastic packaging and medical tubing. BPA is found in epoxy resin and polycarbonate plastics that make up plastics used in water bottles, food storage containers, the linings of metal cans, dental sealants, and thermal paper used for receipts. Minimize your use of plastic water bottles and food containers, especially when heated, and use more sustainable and healthier materials like stainless steel and glass.
Personal Care Items
Skincare products and makeup are other common sources of xenoestrogen exposure. Parabens (methylparaben, ethylparaben, propylparaben, and butylparaben) are commonly used as preservatives in skincare products. In addition to cosmetic and personal care items, parabens are extensively used in pharmaceuticals and food products due to their antimicrobial activity. Be mindful of personal care and beauty products you use, as these products can become absorbed through the skin or respiratory tract. Avoid products with phthalates and parabens, like synthetic fragrances. Instead, opt for all-natural, biodegradable laundry and household cleaning products.
Food
Other xenoestrogens include polychlorinated biphenyls (PCBs), which are industrial chemicals historically used as pesticides and coolants. Despite being banned many years ago, PCBs are still present in the food supply, with fish, dairy, hamburger meat, and poultry being amongst the most contaminated food sources. Since one of the primary sources of exposure to xenoestrogens is food, opt for organic food whenever possible, like hormone-free organic meats and dairy products.
Resources to Help Minimize Xenoestrogen Exposure
The EWG website https://www.ewg.org/ A resource to evaluate the safety of personal care products and foods.
Resources for testing
Cyrex Labs https://www.cyrexlabs.com/