Anyway, I've been following the Eastman Chemical versus CertiChem/PlastiPure kerfluffle with some interest, which is why I'm bringing this article from this week's Chemical and Engineering News by Alex Tullo:
An obscure conflict over a plastic is raising big issues in the field of material safety assessment. Two related Texas-based firms, PlastiPure and CertiChem, are accusing Eastman Chemical of trying to “squelch” science they say shows that Eastman’s Tritan polymer exhibits estrogenic activity. In turn, Eastman charges that the two firms are trying to malign its product for commercial gain.
The controversy hits at one of the selling points of Tritan—that it is free of bisphenol A, an estrogen-disrupting compound. Tritan is a copolymer of dimethyl terephthalate, 1,4-cyclohexanedimethanol, and 2,2,4,4-tetramethyl-1,3-cyclobutanediol. Eastman designed it as a clear, tough, dishwasher-safe polyester that could compete with polycarbonate, which is made with bisphenol A.
Eastman introduced Tritan in 2007, just when the controversy over bisphenol A came to a head and retailers led by Walmart were banning polycarbonate in baby products, such as bottles and sippy cups. Tritan got a lift as a ready replacement, but the claims by PlastiPure and CertiChem now pose a challenge to its success.
CertiChem, founded by George Bittner, a professor of neurobiology and pharmacology at the University of Texas, Austin, offers third-party testing of materials to detect estrogenic activity using an MCF-7 cancer-cell-line assay. Chemicals that bind to estrogen receptors in the cells cause them to proliferate. PlastiPure, also founded by Bittner, develops plastic compounds that are free of estrogenic activity, according to this test. PlastiPure’s work has received support from the National Science Foundation and the National Institutes of Health.I've always wondered what could be estrogenic about Tritan -- neither cyclohexanedimethanol or a cyclobutanediol moiety could be problematic. (I'm pretty sure I got my wife a Tritan water bottle in the last couple of years...) But the terephthalate might be an issue? Hard to say.
Also, I'm less than convinced by CertiChem's technique of calling just about all plastics estrogenic by using the MCF-7 assay. But I'm no endocrine scientist... Readers, what do you think?