“What if our perception of normal exposure is skewed?”: Analyzing the Science of BPA

SarahBlennerBy Sarah Blenner, JD, MPH

Bisphenol A (BPA) is an estrogen mimicking chemical commonly used to create both polycarbonate plastics and the resin lining of cans.  This chemical can be found in plastic food and beverage containers, cans, dental sealants, household products, cell phones, computers, and medical devices.  Hundreds of studies link the synthetic hormone, BPA, to a variety of adverse health conditions, including, breast cancer, prostate cancer, ADHD, autism, obesity, insulin resistance, type 2 diabetes, liver enzyme abnormalities, early onset of puberty, and cardiovascular disease.

In a study conducted by the CDC, scientists found that BPA was present in 93% of Americans tested, signifying the high prevalence of BPA exposure in the American population.  One participant of the “Is It In Us?” study, which measured the presence of toxic chemicals, such as BPA, in the blood and urine of participants, was relieved to know that her results were no different than the results of most of the other participants.  But then she thought: “what if our perception of normal exposure […] is skewed?

Last May, Chicago became the third jurisdiction in the United States to successfully pass legislation regarding Bisphenol A when it banned the sale of baby bottles and other empty food and liquid receptacles intended for the use by children under the age of three.  Prior to Chicago City Council’s passage of the BPA Free Kids Ordinance, the State of Minnesota and Suffolk County New York passed legislation regulating BPA.  In June, Connecticut became the fourth jurisdiction in the United States to address the health risks of BPA through legislation, when it passed an “Act Concerning Banning Bisphenol-A in Children’s Products and Food Products.”  According to the Public Act, beginning October 1, 2011, the sale of infant formula, baby food, and reusable food or beverage containers that contain the chemical Bisphenol A will be banned.

These state, county, and municipal jurisdictions are passing legislation that contradicts the Food and Drug Administration’s (FDA) firm stance that BPA is safe even at levels higher than those found to cause harm in lab animals.  Why does the FDA believe that BPA is safe and why are jurisdictions in the United States acting to protect their citizens from the potential harm of Bisphenol A?  Perhaps it is because of the close ties between the chemical industry and the FDA or perhaps it is because of the chemical industry’s efforts to create “manufactured doubt” regarding the actual health impact of low dose exposure to BPA.

According to a recent article appearing in the Milwaukee Journal Sentinel, journalists uncovered a significant number of communications from the past nine years between the FDA and the chemical industry regarding the health risks (or “lack thereof”) of BPA.   One email, produced as a result of a Freedom of Information Act request and written by Mitchell Cheeseman, Deputy Director of the FDA’s Center for Food Safety and Applied Nutrition, to Steven Hentges, Executive Director of the Chemical Association’s BPA Group stated: “I’d like to get information together that our chemists could look at to determine if there are problems with that data in advance of possibly reviewing the study.”  Cheeseman sent this email to Hentges in an effort to refute a Japanese study finding harm to pregnant women who are exposed to BPA before government scientists had reviewed the merits or findings of the Japanese study.

The close relationship between the chemical industry, a private interest group, and the federal government agency charged with protecting the health and safety of its constituents is disconcerting.  Equally as worrisome is the science that policymakers who claim BPA is safe may be relying on.  According to Frederick S. vom Saal, Curators’ Professor, Division of Biological Sciences at the University of Missouri, the three major factors contributing to whether or not a scientific study finds that BPA causes harm are the source of funding, lack of a positive control, and the type of rat used for research.  According to Dr. vom Saal, of 231 studies investigating the harm of low dose exposure to Bisphenol A, 202 studies demonstrated harm, while 29 studies showed no evidence of harm.  Of these 29 studies, 14 studies were funded by the chemical industry.  Chemical industry funded studies have never determined that BPA shows evidence of harm.  In the United States, the public, activists and scientists alike fear that results of studies are swayed based on the source of funding.  According to Dr. vom Saal, “This is a highly biased distribution of outcomes based on source of funding.”

While Canada has taken precautionary action by banning the sale of baby bottles containing BPA and regulating the amount of BPA that can be introduced to the environment each year, the U.S., the European Union, and Israel (which adopted the European Union’s existing standard) currently have policies permitting the use of BPA in many products, including baby bottles.  It is time that the U.S., the European Union, and Israel protect its constituents from the potential risks of Bisphenol A.  As one concerned citizen puts it: “Sometimes it’s easier not to know” but “once we are made aware, we have a choice either to look the other way or to act on it.  The reality is, all of us have toxic chemicals in our bodies.  It’s the world we live in today.  But we can act together: Now that we are aware, we can act to reduce our exposure, and can help urge changes in the system that allows toxic chemicals into our communities.

2 thoughts on ““What if our perception of normal exposure is skewed?”: Analyzing the Science of BPA

  1. Based on a health survey, the study found that those who had higher amounts of BPA in their urine were more likely to report having heart disease and diabetes. Of course the research presents no information that says the BPA caused these conditions, and the study authors agree that you can’t rule out the possibility that people who already have heart disease or diabetes are more vulnerable to having BPA show up in their samples.

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