Â by Sabrina McCormick, PhD
Are you using personal-care and household products that are linked to breast cancer? While cancer experts estimate that 5% to 10% of breast cancers are hereditary (associated with the BRCA1 and BRCA2 genes), the majority of women who get breast cancer have no family history and no known risk factors for the disease. In an effort to explain the breast cancer epidemic, health experts are looking for clues in the environment… and in the bathrooms, kitchens and pantries of our own homes.
Â According to medical sociologist Sabrina McCormick, PhD, American Association for the Advancement of Science Fellow in the National Center for Environmental Assessment at the Environmental Protection Agency and author of No Family History: The Environmental Links to Breast Cancer, dangerous chemicals found in many of the everyday products we use — cosmetics, lotions, shampoos, household cleaning products and food packaging — may be associated with as many as 90% of breast cancer cases.
Â Scientific Evidence
Â Dr. McCormickâs theory is based on the association between two parallel trends in the same time frame — the rise of breast cancer over the past 60 years (from a lifetime risk of one in 22 women in 1940 to one in eight women in 2008) and the mass production and widespread usage of toxic chemicals that occurred during that period. “As more people have been exposed to carcinogenic chemicals, and as they accumulate in their bodies over time, studies show that several different kinds of cancers have emerged — in particular breast cancer,” she said. Throughout her book, Dr. McCormick cites studies that support the link between toxic chemicals and breast cancer — for example, there is evidence of increased breast cancer risk in the vicinity of polluting facilities. In fact, regional breast cancer rates are highest in the Northeast, which also has the longest history of industrial development and toxic exposure.
Â Is Estrogen the Culprit?
Â How do exposures to toxic chemicals raise oneâs risk for breast cancer? Estrogen seems to be the common denominator, according to Dr. McCormick, who explained that the more estrogen a woman is exposed to over her lifetime, the higher her risk for breast cancer and other reproductive cancers (such as ovarian and uterine cancer). The “estrogen disruptor hypothesis,” which purports that xenoestrogens, chemicals that mimic or disrupt estrogen (found in an abundance of modern-day products), can cause breast cancer is widely accepted in the scientific community. The fact that several of the known risk factors for breast cancer (early onset of menstruation, late menopause, and excess weight) are themselves related to estrogen lends credence to the hypothesis. A number of animal studies provide further support by demonstrating that xenoestrogens cause mammary tissues to grow and also can disrupt sexual and neurological development. In addition to xenoestrogens, other chemicals known or suspected to be carcinogens are found in a variety of everyday products and also could raise oneâs risk for breast cancer and other cancers.
Â What Not To Use…
Â A wide range of personal-care products, household-cleaning products and food packaging contain chemicals that may cause breast cancer or cancer in general. These have been classified by the Breast Cancer Fund, an environmental health advocacy group, as Animal Mammary Gland Carcinogen (AMGC), Human Carcinogenic Risk Classification (HCRC), known Endocrine Disruptor (ED) and other categories described below. To access the Breast Cancer Fund charts by category, go to http://www.breastcancerfund.org. Following is a list of some of the more worrisome substances …
Â Cosmetics and Personal-Care Products
- Parabens, which are chemical preservatives used in cosmetics, deodorants, lotions, ointments and shampoos, are known endocrine disruptors, said Dr. McCormick. While the European Union regulates the use of many parabens in their products, the US does not. (ED)
- Dibutyl phthalate (DBP), which among other purposes is used to make plastics softer, is an ingredient in childrenâs teething toys, nail polish, perfumes, moisturizers and cleaning solvents. (ED)
- Ethelyne Oxide, a compound that adds fragrance to shampoos. (AMGC, HCRC)
- Dioxane, a compound found in shampoos, body washes and sudsing products. (AMGC, HCRC)
- Petrolatum (PAH), which is what petroleum jelly is made of… also used in lipsticks, lotions and oils. (AMGC, HCRC, ED)
- Formaldehyde, benzene and toluene, all found in nail polish and nail polish removers.
- Urethane, found in hair-care products, such as mousses, gels and sprays, and in sunscreens, mascara and foundation. (AMGC, HCRC)
Making matters worse, notes Dr. McCormick, many cosmetics also contain ingredients that act as skin penetrators, which makes it even more likely that these dangerous substances will be absorbed into the skin. Also, beware of products marketed as “youth enhancers” that contain estradiol, estrone or estriol… all forms of estrogen that can be absorbed into the skin that should be used only with medical oversight.
Â For an up-to-date listing of dangerous cosmetics and personal-care products, visit the Environmental Working Groupâs online cosmetic safety database (http://www.cosmeticsdatabase.com).
Â Household ProductsÂ
- Polyvinyl chloride (PVC), a plastic that leaches phthalates, found in cling wraps, plastic bottles, detergents, window cleaner bottles and vinyl shower curtains. Many houses also contain pipes made of PVC, which is a Carcinogen By-product of Manufacturing (CBM) and Hormone Disruptor (HD).
- Diethylene Glycol Monoethyl Ether, found in floor finish, tile and grout cleaner, and microwave oven cleaners. This substance affects the central nervous system and is a reproductive toxin.
- Nonylphenol Ethoxylate, found in cleaners, degreasers, foaming cleaners, air fresheners, spot and stain treatments and metal polish. (ED)
- Nitrilotriacetic Acid, found in carpet-care products, is classified as a Reasonably Anticipated Carcinogen (RAC).
- Tetrachloroethylene, found in spray polish and laundry spot removers.
Many food packages and containers are made with compounds that have been linked to breast cancer, most especially when the package is heated…Â Â
- Bisphenol A, used in the linings of cans and water bottles. (ED)
- Polystyrene, found in Styrofoam food containers, disposable containers, egg cartons and plastic cutlery. (CBM)
- Polycarbonate, found in plastic water bottles and metal food can liners. (ED)
While it may be impossible to avoid all of the products that contain known or suspected breast carcinogens, Dr. McCormick suggests that whenever possible we should use simple, natural personal-care products and buy organic food products to minimize exposure to pesticides and chemicals. She advises using nontoxic cleaning and household products whenever possible, and notes that any household cleaners should be used only in well-ventilated areas. Other precautions include installing a water filter to rid water of contaminants…Â and avoiding packaging that uses plastics and plastic derivatives.
Sabrina McCormick, PhD, author of No Family History: The Environmental Links to Breast Cancer (Rowman & Littlefield) is a Fellow at the American Association for the Advancement of Science in the National Center for Environmental Assessment at the Environmental Protection Agency and is an assistant research faculty at the School of Public Health, George Washington University. She was previously a Robert Wood Johnson Health & Society Scholar at the University of Pennsylvania.