Well, the Tervis Tumbler company is nothing if not responsive.
I already received a reply to my e-mail yesterday inquiring about whether their insulated plastic products contain bisphenol-A, or BPA. That's because I've decided to eliminate my exposure to this toxic chemical as much as possible, by stopping my use of food (or beverage) containers made of plastic that has BPA in it.
I suspected that these wonderful tumblers, which I've been using at home for years, might contain bisphenol-A, for they are super-sturdy and very clear (two big characteristics of BPA). Plus, there is no recycling number on the glasses, another indicator that it's probably a polycarbonite/BPA product.
The answer from the company was a form letter written in January 2010 -- so, obviously, other customers have expressed concern over the BPA issue. Here is the pertinent text:
Thank you for your inquiry concerning recent developments on the safety and use of bisphenol A (BPA) in polycarbonate plastic. Recent media coverage and reports of legislatures considering bills to ban BPA have created questions about this topic.
Our polycarbonate tumblers are made of 100% virgin polycarbonate. BPA is a compound used to make polycarbonate plastic. Tervis Tumbler hired AXYS Analytical Services Ltd. to test water that we stored in a selection of our tumblers for up to 48 hours. Our conclusion from the AXYS results is that our tumblers may have the potential for miniscule levels of BPA estimated to be 0.5 parts per billion or less, to migrate into water. On that basis, one would need to drink 17,000 16 oz glasses or 2,100 gallons of water from our tumblers daily to exceed the recognized safety threshold.
Hmmm ... so, they're admitting there is BPA in the tumblers, but saying it's not enough to be harmful. That leave me in a quandary: Should I resume using them, or leave them on the shelf and keep on drinking out of glass glasses.
For now, I'll stick to the glass, and leave the BPAs on the shelf.