See Nicholas Kristof here.
I asked these doctors what they do in their own homes to reduce risks. They said that they avoid microwaving food in plastic or putting plastics in the dishwasher, because heat may cause chemicals to leach out. And the symposium handed out a reminder card listing “safer plastics” as those marked (usually at the bottom of a container) 1, 2, 4 or 5.
It suggests that the “plastics to avoid” are those numbered 3, 6 and 7 (unless they are also marked “BPA-free”). Yes, the evidence is uncertain, but my weekend project is to go through containers in our house and toss out 3’s, 6’s and 7’s.
I microwave mostly in Ziploc and Glad plastic containers, which are marked 5.