I live by the precautionary principle: If something has been found to cause disease or health problems in animals, and there is some liklihood it could do so in humans as well, I nix it from my life (or try to). Will some of those chemicals be found to be harmless some time in the future? Sure. But in the meantime, I'm taking the conservative route, until we know more. And the truth is that many, many everyday chemicals were developed, put into use and have been building up in our environments and bodies for years (not to mention mixing with other chemicals inside and outside our bodies)—and the vast majority have never been tested for safety. 

Many people think that all chemicals in use today have been tested to make sure they are safe—I have had the discussion with countless people (some who are highly educated) who believe this to be true. It is not. Human beings have developed 10's of thousands (about 50,000 since World War 2) of substances and compounds for all sorts of uses, and the how it works is that if that chemical hasn't been directly linked to a specific problem, it's OK to use.

And it takes significant proof, years of studies, lawsuits (usually) and laws passed (we know how long that can take) to get chemicals eliminated once we do know they are problematic. If this sounds like a broken system to you, let your Congressperson know that you support a bill going through Congress right now: Senate Bill 696: The Safe Chemicals Act of 2013. It includes the sensible requirement that: "chemicals in commerce meet a risk-based safety standard that protects vulnerable and affected populations and the environment." 

Until we have better health and safety protections from potentially harmful chemicals, it is up to us as individuals and communities to avoid possibly harmful substances. Breast cancer is the most common cancer in women and a recent, peer-reviewed study published in Environmental Health Perspectives by a team at the Silent Spring Institute at Harvard looked at reams of animals data from multiple studies, as well as much available human data as they could, and found 17 substances that based on available information, are linked to breast cancers: 

-Automobile and exhaust fumes (avoid exposure to gas and especially diesel fumes from cars but also from weed whacker and lawnmowers—use electric (or a pushmower) instead; fumes from pumping gas are harmful as well)

-Dry cleaning solvents (if you hang dry-cleaning in your car or other closed environment, you are breathing them in; try wet-cleaning or find an 'eco-friendly' or 'green' cleaner as these are usually wet cleaners)

-Flame retardants (if you are buying new furniture, look for those made without these chemical coatings; many natural fibers are naturally flame retardant)

-Tobacco smoke

-Stain-protectors (avoid rugs, upholstry and clothes made with stain-resistant coatings)

-meat cooked at high temperatures (barbequeing, charring, or cooking over a fire; be sure, especially, to vent harmful smoke from cooking this way)

-drinking water disinfectants (use a solid carbon block filter for all drinking water)

-polystyrene (avoid keeping food in clamshell containers, and if you use styrene for hobbies or crafts it can pollute indoor air; it's also used in carpeting)

-non-stick coatings on cookware/PFOA (there are some nontoxic nonstick coatings out there, but you have to look for them; a low-cost solution is iron pots and pans—that's what I use)

As far as already-known causes of breast cancer, the scientists write: "Preventable risk factors for breast cancer include medical radiation, aspects of reproductive history, increased body weight after menopause, lack of physical exercise, alcohol consumption, combination hormone replacement therapy, combination hormonal contraceptives, prenatal diethylstilbestrol (DES) exposure, and probably tobacco smoke."

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