In case you haven't seen it, Environment Canada officially labeled BPA (Bisphenol A) as a toxic substance. This is the stuff that used to be found in plastic baby bottles. Ugh.

Here's the official news release from Environment Canada :
Government of Canada Takes Further Action to Protect Canadians from Risks Posed by Bisphenol A
October 13, 2010
http://www.ec.gc.ca/default.asp?lang=En&n=714D9AAE-1&news=74916A27-7F09-411E-B3AB-D1E8A596A2AC

Personally, we changed to glass bottles, and they've worked fine. As long as you don't drop them