"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
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."
From what I understand, I think 7 is a "grab bag" category - any
plastics that don't meet the 1-6 numbering are placed in 7, so I'd
imagine some 7s are fine and some aren't.