I am awaiting a pick-up of a Sleep Number M7. Not only did it hurt my back, the off gassing made myself & my husband sick. I am looking for a good quality mattress which is not toxic. I don’t know of any Sleep Specialty shops in the Philadelphia area, does anyone? Thanks for any information! 
Hi SleepyGrouchyDopy,
The first place I would start your research is the tutorial post here which has all the basic information, steps, and guidelines that can help you make the best possible choices … and know how and why to avoid the worst ones.
I’m not sure which types of materials you are most comfortable with in a mattress and each person can have a different answer to the question of “how safe is safe enough for me?” but post #2 here and the many posts and sources of information that it links to would be a good place to start to help you sort your way through the conflicting and often misleading information that you will be exposed to on both sides of the discussion about mattress “safety”. For most people who are concerned about safety, making sure that the materials in your mattress (synthetic or natural) are certified (through testing protocols such as CertiPur, Oeko-Tex, or Eco-Institut) would be “safe enough” but there are also others that for personal reasons or who have health issues such as MCS (multiple chemical sensitivities) that may feel more comfortable or are more stringent about the materials in their mattress and prefer to choose more natural materials such as 100% natural latex, natural fibers, or innersprings and avoid synthetic materials completely regardless of how “safe” they may be.
The better options and possibilities I’m aware of in the Philadelphia area are listed in post #4 here.
Phoenix