It's been in the news this past week. Studies are finding that many baby bottles contain bisphenol A (BPA). This chemical leeches out into the liquid. It seems to leech worse when heated or as the bottle gets older. It's concerning to say the least.

http://www.ctv.ca/servlet/ArticleNews/story/CTVNews/20080207/baby_bottles_080207/20080207/

http://www.checnet.org/healthehouse/pdf/plasticchart.pdf

http://www.ctv.ca/servlet/ArticleNews/story/CTVNews/20080130/heat_bottles_080130/20080130/

Here's a list of safe and unsafe bottles.

http://zrecs.blogspot.com/2007/07/z-report-bisphenol-in-polycarbonate.html