Hi always_trying,
There is more about the pros and cons of different types of mattress protectors and some examples of each of them in post #89 here. There is also more about the membranes they use in post #2 here. I wouldn’t consider any of the membrane type of protectors to be unsafe in terms of VOC’s or leaching harmful chemicals but at least two of them are “organic” (although the membrane itself couldn’t be organic) and one of them is Oeko-Tex certified if you have any concerns.
Phoenix