Off Gassing and Memory Foam
Even though memory foam mattresses offer many benefits and rank among the highest for owner satisfaction, some people still have a few complaints or concerns. Off-gassing, or chemical odors, is one issue that is often listed by those considering memory foam. In this article, we will explain the what is behind memory foam off-gassing and odors, potential risks, and how to minimize the problem when shopping. We also compare leading brands and their performance.
Guide to Memory Foam Mattresses & Odor
About 15% of people who buy a memory foam mattress report a noticeable odor. For most people, this is a just a minor annoyance that dissipates within a few days to a few weeks and accounts for less than 2% of returns according to Sleep Like The Dead. However, a small percentage of people may report respiratory irritation and other symptoms like nausea and headaches. We will begin by explaining what causes odors associated with memory foam, and then look at potential risks and differences on odor between different types.
What is Memory Foam Off-Gassing?
All manufactured products have odors based on their components, but the term off-gassing is focused more on the release of Volatile Organic Compounds. Called VOCs, these substances refer to both natural and man-made compounds that have low boiling points and give of aromatic properties as the naturally degrade. Even humans and animals give off methane while plants give off isoprene and terpenes, all natural VOCs. Other sources you may be familiar with include paints and solvents, gasoline and exhaust, new cars and nearly anything else with an odor.
Memory foam is a hi-tech polyurethane foam, a material traditionally made from a range of chemicals. The use of petroleum-based substances is a main cause of off-gassing in foams. Finished foams are largely innocuous, but some manufacturers may also include other VOCs of concern like formaldehyde (a preservative), chlorofluorocarbons/CFCs (blowing agents), and Polybrominated diphenyl ethers/PBDEs (fire retardants). While many of these have been banned or voluntarily phased out, brands are not required to disclose full chemical contents of their products and imported brands may not follow the same standards as US and EU companies.
Is Memory Foam Off-Gassing Dangerous?
In people with sensitive respiratory systems or chemical sensitivities, eye, nose and throat irritation, nausea, and headaches may develop with strong or sustained exposure, but generally disappear shortly after. More dangerous VOCs have been linked longer-term effects like central nervous system damage, organ damage, and cancer. However, for memory foams produced under current regulations, there are no credible studies showing health risks caused by VOCs or chemicals.
The chemicals deemed most dangerous to people and the environment that are relevant to memory foam include PBDEs, formaldehyde, and CFCs, which may be found in the foams, adhesives or in flame-resistant treatments. PBDEs can be used to meet fire-safety guidelines, but the types found to be carcinogenic have been banned in the EU and voluntarily discontinued in the US since about 2005. Many manufacturers have switched instead to fire-sock barriers instead. Formaldehyde is one of the most harmful substances, and also one of the most heavily regulated. It can be present in variety of different applications (especially lower-cost ones) from foams to adhesives to flame retardants either directly as a by-product, though some manufacturers take care to avoid use. Methylene chloride is a volatile solvent that can be used in the memory foam manufacturing process. It is a potential carcinogen, and its use has significantly declined with EU limits and tighter pollution restrictions in recent years. CFCs were used by some manufacturers as blowing agents, in order to create the gas reaction that makes foam. These have also largely been banned since the 1990s due to environmental pollution concerns.
According the to the Polyurethane Foam Association and the EPA, finished flexible polyurethane foams do not represent a health hazard. While VOCs found in memory foam will vary by formulation, most manufacturers, especially those in the US and EU, have eliminated the most harmful VOCs. Other chemicals of concern like pthalates are also not widely used. However, there may be cases of non-compliance, and different standards in other countries and regions..
CertiPUR-US is an independence organization developed by US and European industries which tests polyurethane foams for emissions, harmful chemicals (including formaldehyde, CFCs, methylene chloride, heavy metals, banned pthalates and PBDEs), and durability. Only those foams found to have low VOC emissions (under 0.50 mg/m3) and meeting the other requirements are certified. This designation can be useful for shoppers who are concerned about odors and chemicals.
How to Minimize Odor and Off-Gassing
If you find yourself at odds with the off gassing of your memory foam mattress, remember that you have options.Not all types of foams have similar levels of off-gassing. Checking for the CertiPUR certification can be a good start at avoiding foams with odors that may be hazardous. In addition to the chemicals used in manufacturing, the density of memory foam also plays a role. Lower density foams have less polymers and are thus less likely to have strong odors.
There are also alternative memory foam mattresses available such as plant-based and gel that may have lower levels of odor than traditional options. Plant-based memory foams utilize less VOC-producing petroleum products and may be manufactured in a method more conscious of chemicals and odors. Gel foams may also reduce odor by reducing the amount of memory foam present. Other lines may also add scents like green tea to mask odors.
After purchase, there are also steps that can minimize exposure or inconvenience. Unpacking the mattress and allowing it air out in a well-ventilated space for a few days is usually the most recommended method. This is why beds in stores and showrooms typically have no noticeable odor. Note that packaging plastics can also contribute to odors, so removing packing materials is important to reducing potential odors.
Memory Foam Brands and Off-Gassing Complaints
Below is a comparison table of leading brands. We looked at reviews from consumer websites, third-party product review sites and other sources to see how often people complained of bad odors or side effects. We also provided information on foam type, density, and certifications for comparison purposes.
|Amerisleep||Plant-Based||3%||4.6 / 5||4.5-5.3 lb||CertiPUR|
|BedInABox||Gel/Traditional||15%||4.4 / 5||3.0 lb||CertiPUR|
|BodiPedic||Traditional||8%||4.0 / 5||2.5-3.0 lb|
|Novaform||Gel/Traditional||15%||4.0 / 5||3.0-3.5 lb|
|Sealy Optimum||Gel/Traditional||9%||4.1 / 5||3.7-4.0|
|Serta iComfort||Gel||6%||4.2 / 5||3.0-5.0 lb|
|Simmons Curv||Traditional||na||na||2.0-3.0 lb||CertiPUR|
|Simmons Comforpedic||Gel/Traditional||6%||4.1 / 5||3.5-4.5 lb|
|Sleep Science||Traditional||12%||3.5 / 5||5.0 lb|
|Tempurpedic||Traditional||18%||3.8 / 5||2.5-7.0 lb|
Of the brands covered above, only Amerisleep, BedInABox and Simmons Curv have met CertiPUR standards. Neither Serta, nor Sealy, nor Simmons Comforpedic mention anything on their website about health, chemicals or certifications. Tempurpedic does not have any information on their website that we could find about chemicals, VOCs or product safety, other than to say odors are harmless. The other discount store brands, BodiPedic, Novaform and Sleep Science also do not mention chemicals or VOCs in product materials
The brand with the lowest rate of odor complaints (less than 3%) was Amerisleep, which uses plant-based, medium-density memory foam priced in the mid-level range. Simmons Comforpedic and Serta iComfort were a little higher at 6%, both using a mix of gel and traditional foams with medium range densities and mid- to high range prices. BodyPedic and Sealy Optimum both came in under 10% as well, Bodipedic being a traditional low-density, low-cost option and the Optimum using gel and traditional foams with medium density. Sleep Science, Novaform, and BedInABox all had higher rates of odor complaints within the average to high range of 10-15%, and use mostly traditional medium-to-high density foams in the mid- to low price range. The brand with the highest rate of odor complaints (18%) was Tempurpedic, who uses medium to high density memory foams in the higher price range, with nearly 1/5 reviews mentioning strong odor.
Over the past two decades since memory foam mattresses first were introduced, they have continued gaining popularity due to comfort, pain relief, and longevity that typically rates well above standard spring mattresses. The downsides such as odor and heat, while legitimate concerns, can vary from manufacturer to manufacturer and are not necessarily universal. The industry as a whole continues to grow, and many brands have been receptive to consumer concerns by making efforts to reduce chemicals and further improve comfort. If you are considering a memory foam mattress for the benefits they offer but have reservations due to off-gassing, consider the risks and range of options that may still meet your needs. While brands will rarely disclose trade secret information, checking for independent certifications like CertiPUR and reading memory foam mattress reviews can help you locate a mattress that doesn’t smell up your bedroom or pose a health risk.