Hi ttight1,
As far as I know they haven’t changed their materials but they would be the best source of information about any recent changes they have made to their mattresses. The “official” information that I was given when Reverie became a member of the site was that their latex was “at least” 60% natural rubber but they may have been understating it just to be on the safe side so if the natural rubber content in their latex is higher than that then I would consider it to be a “bonus”.
All the latex you are likely to encounter (Dunlop or Talalay made with either natural or synthetic rubber or a blend of both) will have been certified by either Oeko-Tex or Eco-Institut for harmful substances and VOC’s (see post #2 here) and in general I would consider any type or blend of latex to be a very “safe” material in terms of harmful substances and VOC’s.
Phoenix