The Tempur mattress is made up of two types of polyurethane foam. A standard, mid-density material and a visco-elastic poly (visco-elastic or "memory foam" is a polyurethane with a petrochemical slowing agent). Polyurethane foam consists of two main ingredients, Polyol and TDI. TDI stands for Toluene diisocyanate (spell check was no help on that). Both chemicals are known to cause respiratory distress (search "diisocyanate asthma"). The two foams are attached with an adhesive which is also potentially volatile (unknown glue). The cover of the Tempur used to be, and may still be, backed with a PVC coating (polyvinyl chloride) which is also linked to asthma as well as a myriad of other problems (I haven't looked at one of their covers for quite a while but last I knew it was still there). Buying a mattress is hard enough without having to worry about toxins. Sorry to hear about your trouble and apologies if you've already heard all this. I do agree that they should have to warn people with asthma and breathing problems about the potential risks involved with volatile components. They also are not the only ones, however---polyurethane and vinyl are ubiquitous (especially in hospitals!!) and are found in most every conventional mattress, couch or upholstered chair.