Welcome To The Toxic Shell Game

Like most parents, CEH Executive Director Michael Green doesn’t always see eye-to-eye with his kids. Michael bought his daughter Juliette a stainless-steel sippy cup to use in place of her favorite plastic cup. But Juliette wasn’t about to give up her sippy cup without a fight.

As this month’s Mother Jones magazine cover story, “Are Any Plastics Safe recounts, this disagreement formed the foundation of a two year effort by CEH to find out if plastic sippy cups, including cups labeled “BPA-free,” could pose health threats to children.

The result: our testing found 9 out of 35 sippy cups we tested were found with significant amounts of estrogenic activity, including seven cups found with more estrogenic activity than a cup made with BPA (see results below). All of the nine estrogenic cups were labeled “BPA-Free.”

The hormone-altering chemical bisphenol A (BPA) has been banned from baby bottles and cups for young children (including sippy cups) in California (and in some EU countries), and nationwide most companies have removed the chemical from these products. BPA is estrogenic, meaning it can mimic the action of estrogen, a powerful hormone that controls sexual development, is important in conception and during pregnancy, and plays a role in the growth of some breast cancers. Scientists have found in animal studies that even very low levels of BPA exposure can lead to health problems, including harm to the mammary gland, ovaries, pituitary gland, and impacts on brain development, reproduction, and other health concerns.

Many parents assume that a sippy cup labeled “BPA-free” must be safe, or at least must be free of estrogenic health threats. But because there are no rules in the U.S. that require companies to disclose the chemicals they use in products sold for our children and families, there is no way to know if the chemicals used to replace BPA might be just as –or even more—harmful. This toxic shell game puts us all at risk from unknown and untested chemicals in hundreds of everyday products.

In 2011, CEH decided to begin testing sippy cups for estrogenic activity. Since we can’t know what chemicals companies could be using, it’s not possible to test for any particular hormone-altering substances. But recently scientists have developed tests that can show if certain materials, including plastics, could produce estrogenic effects.

We purchased several brands of sippy cups between October 2011 and March 2013. We commissioned two independent labs, one a commercial company called CertiChem, the other a research lab at the University of California at Davis, to conduct testing for estrogenic activity. In all, we tested 35 sippy cups. We had the brands  that were found to be positive for estrogenic activity by the first lab re-tested at the second lab (except one, which we had not found for sale at the time of  the 1st testing) to be sure the results were consistent. We had the first lab test two parts of each sippy cup: the cup that contains the beverage the toddler drinks, and the spout that toddlers put their mouths on.

Our findings (link to results below) showed that nine sippy cups tested for moderate to high levels of estrogenic activity. Alarmingly, seven cups tested for higher levels of estrogenic activity than a cup made with BPA!

These findings are an important warning to parents, and also show that we urgently need to modernize our outdated, inadequate federal chemical safety laws. Congress is now considering the first new chemical safety rules in four decades, but unfortunately their latest proposal would actually leave American children and families at risk from harmful chemicals. CEH is calling for chemical regulations that end the toxic shell game and provide real safety protections for our children and families.

Our findings

Seven sippy cups (two brands) had more estrogenic activity than a BPA-containing cup (including one brand which came in 6 different characters):

Six First Years Disney Insulated Color Changing cups (estrogenic activity was in the color changing cup)


CarsCars CarsFairies CarsMinnie Mouse
CarsMickey Mouse Clubhouse CarsMonster’s Inc. (girl) CarsMonster’s Inc. (boy)
CarsGerber Graduate’s Color Changing Cup (estrogenic activity was only in the blue color changing cup)

Two cups (two brands) had over half as much estrogenic activity as the BPA cup:


CarsCamelBack Hearts Spill Proof Cup (estrogenic activity was in light purple cup) CarsBorn Free Disney Mickey Mouse Soft Spout Cup (estrogenic activity was in the dark blue spout)