what is the waterproof membrane made of?
Open Here's what Naturalmat had to say about the waterproof membrane in the Natural Mat Organic Crib Mattress Protector, "... the waterproof membrane is made from polyurethane. Although this is a type of plastic it is not harmful and the composition is nothing like PVC. Polyurethane can be found in a number of textiles including bathing suits. The membrane only makes up 5% of the total product. (So the overall product is 95% organic.) Due to fact that the membrane only makes up a very small percentage of the product it has been approved by the Soil asociation as an organic textile."