When I originally heard about this a few years ago, the studies showed a danger of hormone leeching into foods that were heated in plastic containers (like in the microwave oven). That was based on studies done and published in Europe. They linked it to problems with male infertility. The report then was that this material was used in everything from soda bottles to tupperware to baby bottles, but that the main danger was in using the container to heat things in. The studies seem to have expanded since then.

I do know that with the progression of this news, Guyot stainless steel bottles have become difficult for us to get. It's hard to know what to believe with all the "experts" arguing.