Sealy, Simmons, Serta, Tempurpedic, Restonic etc... mattress manufactures come from the Urethane Industry. They specialize in urethane mattresses and mattresses made from synthetic materials. Organic mattress manufacturers come from the organic industry giving you a much higher quality mattress expressed in the high level of purity, comfort and longevity.
Formaldehyde is in all "non-organic" mattresses. According to the Cancer Institute, In 2011, the National Toxicology Program, an interagency program of the Department of Health and Human Services, named formaldehyde as a known human carcinogen in its 12th Report on Carcinogens (1).
(Smart Latex (tm) is a word they invented to describe "synthetic" latex)
Synthetic Latex Rubber isStyrene Butadiene Rubber. According to the National Institute of Health (NIH) Styrene is reasonably anticipated to be a human carcinogen. (2). 1,3 Butadiene is listed as a known carcinogen by the Agency for Toxic Substances Disease Registry and the US EPA.(3) Health effects to the exposure to Butadiene.(4)
Sterns and Foster uses poly-urethane foam edge encasement in most models. This means chemical flame retardants are used, poly-urethane foam breaks down as you sit on the edge over time and you loose significant sleeping surface.
1. National Toxicology Program (June 2011). Report on Carcinogens, Twelfth Edition. Department of Health and Human Services, Public Health Service, National Toxicology Program. Retrieved June 10, 2011, from: http://ntp.niehs.nih.gov/go/roc12.