Hi edgerlys,
Yes she does believe that (or at least she did when she posted) but she isn’t correct and you can my thoughts about this in my reply to her here.
The most reliable way to assess the “safety” of a foam material would be based on the testing that is done for harmful substances and VOC’s and all the latex you are likely to encounter (Dunlop or Talalay made from synthetic or natural rubber or a blend of the two) would either be Oeko-Tex or Eco-Institut certified which would generally be considered to be very safe. For those who are in more challenging circumstances and believe they may be more sensitive than the large majority of the population or have medical conditions such as MCS (multiple chemical sensitivities) then post #2 here and the many posts and sources of information it links to can help answer the question of “how safe is safe enough for me” but this can be a very frustrating and difficult area of research when you are trying to research the specific composition of every material in a mattress that in many cases you may not be able to find out (such as the specific chemistry or compounding formula of a foam).
Post #2 here includes many links to most of the better forum posts about mattresses and children.
You can see my thoughts about making your own mattress in post #15 here and the posts it links to in option 3 but it’s certainly not necessary in terms of safety.
While I would tend to avoid memory foam with mattresses that young children sleep on … whether a material is “safe enough for you” based on a particular certification would be an individual judgement. Just like there are some people who believe in organic food and others aren’t quite so stringent about their diet … each person may have a different set of priorities that are important to them. There are many parents that are fine with polyfoam that is either made in the US or is CertiPur certified and others that wish to avoid primarily petrochemical foams such as polyfoam completely even if the testing appears to indicate that it is safe and they may be more comfortable with materials like innersprings, natural latex, and natural fibers along with “safe” fire barriers such as wool or viscose/silica inherent fire barriers (or possibly even boric acid) just as an additional measure of “safety” or for the sake of their own peace of mind. You will often see scare tactics on one side of the “safety” argument and you will also see arguments on the other side that tend to minimize the risks of some of the more questionable materials or the chemicals that may be in some mattresses but if you stick with materials that have been certified and avoid the materials that are known to create issues with some people that may be more sensitive then you will likely be fine in terms of safety.
Phoenix