Hi MidwestGirl,
I think you are wise to be cautious when thinking about foam when it comes to the effect on children (and on adults) but it’s also important to know that all foam is not the same.
There are really 3 main types of foam. These are memory foam, polyurethane foam, and latex foam. The first two are made from various chemicals (primarily a polyol and an isocyanate) and the last is made from natural rubber (NR), synthetic rubber (SBR), or a blend of the two.
Of these 3, I believe memory foam should be avoided completely for infants and young children and not just because of concerns about chemicals and offgassing. Post #2 here has more of my thoughts about this and this thread and post #2 here and post #21 here also has more information about infants/children and mattresses.
Polyfoam tends to be a little less risky because of how it is made but I would still tend to avoid it if your budget makes it possible and stick with safer or more natural materials. At the very least … I would make sure that any polyfoam in a mattress that may be used for children is either Certipur or Oeko-Tex certified (or certified by another reputable agency such as GreenGuard).
I believe that both blended and natural talalay latex OekoTex standard 100 class 1 (which are both
“safe for babies” certified) and 100% natural Dunlop latex would make good choices.
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Natural or organic fibers also make very good choices (with no harmful chemicals added or used in manufacturing).
Articles and sites like the one you mentioned are well worth reading and are an important part of good research IMO but there is sometimes also a danger that they can be so scary that people may overreact and lump almost everything into the “harmful” category and overlook some of the many safer and better choices that are available.
Phoenix