Can women reduce their breast cancer risk by avoiding certain everyday chemicals?

According to the authors of a study published by the U.S. National Institutes of Health (NIH), the answer is “yes”. 

The authors found that animal (rodent) tests identify human breast carcinogens accurately enough to use that data to expand and rank the list of possible breast cancer triggers.

Only about one in 10 breast cancers (10 percent) stem from genetic causes, and scientists believe that environmental factors, including exposure to chemicals, plays a huge role.

Study expands and ranks list of chemicals risky for breast health
The new research comes from scientists at Boston's Harvard School of Public Health, and the nearby Silent Spring Institute in Newton, Massachusetts (Rudel RA et al. 2014).

Their study ranks the riskiest chemicals for women's bodies, and the U.S. NIH says it will use its recommendations when it tests about 50,000 tissue samples in a major breast cancer study.

“The study provides a road map for breast cancer prevention by identifying high-priority chemicals that women are most commonly exposed to and demonstrates how to measure exposure,” said study author Ruthann Rudel, MS, research director at the Silent Spring Institute.

Importantly, as Rudel said, “This information will guide efforts to reduce exposure to chemicals linked to breast cancer, and help researchers study how women are being affected.”

The study identified more than a dozen types of chemicals as “high priority” to avoid because they are common and consistently cause mammary tumors in animal studies. 

“Every woman in America has been exposed to chemicals that may increase her risk of getting breast cancer. Unfortunately, the link between toxic chemicals and breast cancer has largely been ignored,” said co-author Julia Brody, PhD, executive director at Silent Spring Institute.
“Reducing chemical exposures could save many, many women's lives.”

Study lists worst chemicals for women to avoid
Based on the available evidence, the report's authors advised women to start avoiding the riskiest chemicals:

Charred Food
Burning food or heating cooking oils to their smoking points can create carcinogens and put them into your air and food. Use a ventilation fan, cook on your back burners, and limit consumption of burned or charred food.

Avoid eating or drinking from Styrofoam cups and takeout containers, since styrene was identified as a “reasonably anticipated human carcinogen.” Instead, drink coffee out of reusable, food-grade stainless steel containers. Styrene also occurs in tobacco smoke.

Toxic Chairs and Couches
Carcinogenic flame-retardants are found in most polyurethane foam used in furniture. Call the manufacturer and see if the foam in a model you like is coated in flame retardants. (California's decision to repeal its requirement that foam in furniture be flame resistant should spread flame retardant-free furniture nationwide.

Stain-Resistant, Non-Stick Coatings
Stain-resistant rugs, furniture, and fabrics and nonstick pots and pans are linked to breast cancer and to thyroid disease and obesity. Use non-treated stainless steel or cast iron cookware, and avoid carpeting, furniture treatments, or clothing labeled “stain repellent” or “stain resistant”.

Toxic Dry-Cleaning Chemicals
The common dry cleaning chemical perchloroethylene or “perc” was deemed a probable human carcinogen, with ties to liver, kidney, and nervous system damage. Use other, safer options such as silicone-based dry cleaning services. 

Use these tips to get clothes clean without shrinking them:
  • Wool: Gently hand-wash with a mild soap in 100-degree F water. Add a little distilled white vinegar to the water when you rinse, and then lay it flat and stretch it to its original size to dry. Always keep wool out of the sun to dry. (Wash cashmere, alpaca, angora, or mohair using the same method.)
  • Rayon: Hand-wash in cool water with soap or detergent and rinse. Don't twist or wring out the water; press it out of the garment after rinsing.
  • Silk: Hand-swirl silk gently in 100- to 120-degree F water with some gentle castile soap with a neutral pH. Hang indoors to dry, as UV rays can damage silk. Hang in a steamy bathroom to get out any wrinkles.
Contaminants in Unfiltered Drinking Water
Water disinfection byproducts and chemical farming chemicals occur in some drinking water. Purchase an NSF-approved solid carbon block drinking water filter.
Bottled water is not necessarily better, as a recently study detected nearly 25,000 different chemicals in bottled water.

Gas/Exhaust Fumes and Scented Candles
Gasoline and chemicals formed by combustion (benzene and butadiene) rank as major sources of breast carcinogens. It comes from gas cans in your basement or attached garage and in exhaust from diesel or other fuel combustion, including vehicles and lawn equipment.
Don't idle your car, and support anti-idling and fuel efficiency regulations. Use electric lawn mowers, leaf blowers, and weed whackers. Don't burn scented candles, either, as they release benzene.

Toxic Dust Bunnies
Many of the chemicals on the report's high-priority list wind up in household dust, which acts like a magnet and sucks in tiny amounts of toxins.
Remove your shoes at the door, vacuum with a HEPA filter, and clean floors and surfaces often with a damp rag or mop.

Cigarette Smoke
Cigarette smoke contains cancer-causing materials like styrene, benzene, and 1,3-Butadiene … the same things found in Styrofoam cups and tailpipe exhaust. Quit smoking and do your best to stay out of homes, restaurants, and bars that allow smoking.

Ink-Jet Printers
Many printers spew aromatic amines, benzidine and aniline dyes, and combustion products linked to cancer. Avoid printing unless absolutely necessary, and share files online instead. If you must print, do it in a well-ventilated area. 

Driveway Sealant
Coal tar sealants are banned for use on roadways, but are sstill available use on blacktop in home driveways and parking lots. The toxic PAHs in them readily convert to dust.
If you're coating your own driveway, make sure you opt for asphalt sealant that is free of any coal tars. If you're installing a new driveway, choose gravel or some other permeable surface.

Grilled and Browned Meat
Heterocyclic amines and PAHs created when grilling or browning meat are linked to cancer. Fortunately, grilling fish does not create anywhere the same levels of these toxins:
  • A Swiss study (Gross GA et al. 1993) found no detectable levels of HCAs in grilled fish. It is reasonable to assume that fish grilled lightly (i.e., until just done), without the skin and its fatty under layer, will contain the lowest levels of HCAs.
  • According to the authors of a recent review article from Japan, where people eat far more fish than meat and where, accordingly, grilled fish constitute the single greatest source of HCAs, “…the content of HCAs in dishes consumed in ordinary life is low and not sufficient in itself to explain human cancer…” (Sugimura T 2004).
For tips on how to make grilling as safe as possible, see the “Keeping grilled seafood safe” section of “Cooking Fish Over Fire: Our Guide to Great Grilling

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