[Greenhomeguide.com] "Memory foam is, simply put, foam made from polyurethane. Also called visco-elastic polyurethane foam, memory foam poses various health and environmental concerns:
- Petroleum. Polyurethane is synthetic and is made from petroleum products. Therefore, its production furthers our dependency on fossil fuel resources. The production of synthetics from petroleum products is energy-intensive and often generates toxic waste byproducts.
- Not biodegradable. Polyurethane foam is not biodegradable, and it ends up in the landfill for a very long time.
- VOCs. The chemicals in new polyurethane foam outgas into the air. These toxic chemicals are called VOCs, or volatile organic compounds, and you can often smell them until they dissipate. Most of the VOCs from polyurethane foam dissipate in several weeks to several months, depending on many variables, such as the types and amounts of synthetic materials; amount of fresh-air exchange in the room; temperature and humidity; and breathability of bedding materials like comforters and bedspreads.
- PBDE flame retardants. All mattresses made with synthetic foams, batting, or fabrics must be treated with flame-retarding chemicals so that they meet the federal open-flame flammability test. Whether a mattress is made with standard polyurethane foam, memory foam, recycled polyurethane foam, Dacron, or even a combination of soy-based and polyurethane foams, there's no getting around the problem of flame retardants. Although bioaccumulative PBDEs, the most toxic flame-retardant chemicals, have been voluntarily discontinued by U.S. mattress manufacturers, the alternatives are only somewhat less toxic, and not considered acceptable by the German field of Bau-Biologie. (The measurable Bau-Biologie standards for health are perhaps the most stringent in the world.)
- Organophosphate flame retardants. Flame-retardant chemicals in mattresses that contain any amount of polyurethane foam are called organophosphate chemicals. Unlike VOCs, these chemicals do not become gases, are not easily detectable by smell, and levels may increase over time as the materials age. Even though the levels are chronically low, since your body and face are on the mattress for a third of your life (during your most sensitive regenerative time), it might be best to consider a chemical-free alternative."