We bought a Select Comfort bed about 5 years ago, right before I was diagnosed with MCS. I would not have bought it had I known, but we still have it, and am planning on replacing it with an all wool mattress. The materials in the Select Comfort bed consist of the box spring, which is made of a hard plastic base in a zippered polyester cover. The mattress is a vinyl air mattress (with an air pump attached and plugged into the wall, hence you can choose your "sleep number" by adding or decreasing the air in the vinyl air mattress).It looks exactly like the ones used by people to float on in the water. This is then surrounded by 2 different kinds of foam as filler (which many have had problems with mold due the moisture being trapped), all of this zippered into a polyester case. I am dealing with it at this point by using a wool mattress topper so I am not sleeping directly on the mattress, and using an air purifier in the room. Also, I do not leave the bed plugged in at all, due to being very sensitive to EMF's. This is working ok for me now, but I can't wait to get my whole bedroom "organic".