Sometimes you simply can't avoid using plastic. The Environmental Working Group says you should avoid toys marked with a No. 3 because they're made from polyvinyl chloride (PVC). Even though the chemical phthalate (an endocrine disrupter) was banned recently from new children's toys, there were millions made before the February 2009 ban. EWG also recommends avoiding food containers marked with a No. 7, which can have trace amounts of the chemical bisphenol A in it. If you can't use glass or ceramic, use plastics marked with Nos. 1, 2, 4 or 5, which do not have BPA in them.