After World War II, the United States experienced a chemical revolution. Stockpiles of chemicals developed to fight the war made their way into everyday commerce. Pesticides radically altered age-old agricultural and pest-control practices. Plastics brought modern conveniences into every kitchen. Synthetic chemicals made their way into our everyday products—from BPA in our food can linings to phthalates in our shampoo to flame retardants in our mattresses. It was better living through chemistry.

We now know that our bold rush into the age of synthetic chemistry has come with a hidden cost. Biomonitoring research (measuring chemicals in people) shows that our bodies are home to pesticides, plastics chemicals, heavy metals, flame retardants, and scores of other chemicals. Growing scientific evidence is finding links between chemical exposure and health concerns that are on the rise, including many cancers, metabolic disorders, asthma, learning disabilities, obesity, and neurological disorders such as Alzheimer’s and Parkinson’s.

We embraced the chemical revolution without adequate caution. The federal government didn’t (and still doesn’t) require comprehensive testing to ensure a chemical is safe before it enters the marketplace. The handful of chemicals that have been tested have relied on the outdated rules of toxicology that assume the dose makes the poison—that what matters most is how much of a chemical we’re exposed to. We now know that low-dose exposure, the timing of exposure, the mix of chemicals we are exposed to and interactions between chemicals and our bodily systems and genetics all impact toxicity.

One of the most disconcerting set of chemicals linked to diseases, including breast cancer, are those termed endocrine-disrupting compounds (EDCs), including BPA, phthalates and other chemicals found in our everyday products. EDCs disrupt the body’s hormone systems, which regulate nearly every aspect of the intricate and exquisite process of life—from the awe-inspiring process of fetal development to the dramatic changes in puberty to the everyday processes of turning food into energy. Since one of the known risk factors for breast cancer is increased exposure to estrogen, it stands to reason, and the research bears out, that exposure to endocrine-disrupting chemicals that look like estrogen to our cells would increase the risk of developing the disease.

EDCs are a perfect example of why the “dose makes the poison” logic is flawed. EDCs can sometimes exert their most significant effects at exquisitely small doses. This is no surprise, since the hormones normally affect physical processes at very low doses. Additionally, EDCs can exert more influence during periods of development when hormones orchestrate very profound transformations, like in utero brain or reproductive development or during puberty. In addition, combinations of tiny amounts of different EDCs can actually have a synergistic effect, multiplying one another’s effects beyond the mere sum of the individual exposures.

So how do we right the wrongs of past chemical policy? And how do we ensure that our chemicals-management system is responsive to new and emerging science? We need Congress and the Administration to act swiftly to fix our broken chemicals-management system. A good start would be to act on current and pending legislation to:

1. Effectively regulate cosmetics and phase out the use of carcinogens and reproductive and developmental toxins from the products we put on our bodies every day
2. Require transparency of cleaning product ingredients
3. Phase out the use of EDCs, such as BPA, in food packaging
4. Amend the Toxic Substances Control Act (TSCA), the law which has failed in its task of regulating industrial chemicals, to give EPA the authority to truly protect public health; and
5. Support innovative solutions, such as green chemistry, to replace toxic chemicals with safer alternatives.

The burden of proof must shift to chemical manufactures to prove safety before chemicals enter commerce. Safety testing should incorporate the latest science, taking into account impacts like endocrine disruption. With government and industry action—driven by consumer demand—we need to usher in a new paradigm where chemicals are guilty until proven innocent. Our health depends on it.