There's at least one kind of plastic bottle that is NOT so good for you, or the environment, or the baby. It's the one with the little triangle and the number 7 inside it. The chemical that is under suspicion is popularly known as BPA, that's Bisphenol A, a found in hard, clear polycarbonate plastics. That's triangle-7. It leaches into the liquids it holds. It's suspected of causing cancer, changing hormone levels, and other fun stuff.
The Canadian government is considering whether to declare BPA a toxic chemical. Guess that'llpretty much a stop to some plastic baby bottle sales. So check that number of the bottom of the bottle. LOne more label it pays to read before you buy, or imbibe.
Here's a laugh for the more cynical among us: guess what plastic is used in many of those very expensive, glitzy, brand name, sports drink bottles you see being toted around conspicuously by joggers and bike riders in multi-color uniforms? You got it, good old triangle-7. So they pay extra cash for their upscale drinking utensil to exercise and stay healthy while ingesting some good old-fashioned cancer inducers. Next time you pass an expensive sporting goods store walk inside and look for the little trangle-7 on the bottom of the glitzier plastic stuff.
OK, you can read the New York Times article and they have a picture of the plastic bottle made by Nalgene with the BPA in it. Nalgene acknowledges some may not want the BPA as a food additive so they make bottles without it. Buyer's choice.