A study led by University of California, Davis, toxicologist Michael Denison and CertiChem, Inc. founder George Bittner has allegedly found that some hard, clear thermoplastic resins made without bisphenol A (BPA) still release chemicals with estrogenic activity (EA). George Bittner, et al., “Chemicals having estrogenic activity can be released from some bisphenol a-free, hard and clear, thermoplastic resins,” Environmental Health, December 2014. According to the study, which used in vitro assays “to quantify the EA of chemicals leached into ethanol or water/saline extracts of fourteen unstressed or stressed (autoclaving, microwaving, UV radiation) thermoplastic resins,” four types of resin “leached chemicals having significant levels of EA.”

In particular, the authors noted that UV radiation increased the probability that certain thermoplastic resins would leach chemicals with detectable EA levels. However, the study stopped short of assigning any human health effects to the consumption of these chemicals, as no scientists or other entities “have identified and characterized the EA and anti-EA of all chemicals and their metabolites in these extracts.” Additional details about Bittner’s previous work appear in Issue 519 of this Update. See Mother Jones, December 1, 2014.