Memory Foam Mattress Ingredients: are the dangers real or exaggerated?
Are the chemicals in your life freaking you out or have you found yourself wondering if products like memory foam mattresses are safe? If you’ve been looking into this type of mattress or any other, you may be wondering whether chemicals and odors could represent a real danger.
The concern is definitely a valid one, as we spend nearly one-third of our lives in bed on a mattress. Not to mention, all too often some new material or product is seemingly trying to kill us.
From flame retardants to foaming agents, the ingredients used on some memory foam beds can certainly raise some eyebrows. Many websites discuss toxins and other potential problems created by synthetic chemicals which has brought the issue to the forefront.
Knowledge is power, right? In this article, we will look at memory foam ingredients, research, consumer information and product comparisons to assess memory foam safety. Some mattresses are safer than others and after reading this you’ll know how to tell the difference.
A Look Inside Memory Foam Mattresses
So, what are these things made of? Memory foam beds all have two core components: a polyurethane memory foam layer and a polyurethane foam core layer. These layers are wrapped in some type of fabric, and all mattresses must also have flameproofing of some sort to meet federal safety laws.
Some brands may include other materials as well such as gel or gel-infused foam, latex foam, or padding from polyester, wool or cotton. Most people are fairly familiar with these types of materials. The components people are usually concerned about are the memory foam itself and fire-proofing chemicals, which we will take a closer look at below.
Memory Foam & Polyurethane Foam Components
- Polyols – the binder/bulk ingredient. Usually composed of petroleum oil-derived ingredients, but may also include botanical sources like soy or castor beans.
- Diisocyanates – the reactive ingredient. Reacts with the polyols and blowing agent to produce a flexible polyurethane foam. The most commonly used sources are MDI and TDI, which alone in raw forms can cause respiratory and dermal sensitization and may be carcinogenic. MDI is regarded as the safer and less toxic option, and is known to be the least hazardous organic isocyanate. The primary hazard with these compounds is during manufacturing; after reacting they are inert but can offgas.
- Blowing Agents – introduces carbon to create the foam. Used to use CFCs, though today manufacturers may use water, HFC or other agents.
Possible Ingredients/Byproducts of Concern
Which ingredients are causing all the trouble? There are some other chemicals that can be in memory foam, however the ingredients used in a specific brand’s memory foam are considered trade secret and are not required to be released. Often, pinpointing the components is impossible.
The good thing is that US laws and voluntary restrictions have phased out most of the more concerning chemicals that could be present in memory foam, though these would not necessarily apply to imports.
Here are chemicals that can be or have been found in memory foam and potential issues. Note that each manufacturer uses their own “recipe”, so these do not apply to all lines.
- Methylene dianiline / MDA – suspected carcinogen, eye and skin irritant, liver and thyroid damage with ingestion. Household products produce very low levels, greatest risk is during manufacturing.
- Vinilideine chloride – eye and respiratory irritation, possible carcinogen, organ damage. Primary hazard is during manufacturing.
- Methyl benzene – inhalation can affect nervous system.
- Dimethylformamide – organ damage possible, and possible carcinogen, though primary risk is during manufacturing.
- Acetone – toxic when inhaled in large amounts, but limited effects with low exposure.
- Methylene chloride – a solvent, mucous membrane irritant and potential carcinogen. Use has declined in recent years due to EU restrictions and pollution regulations.
- Formaldehyde – typically not added to foams, but may result as a byproduct of chemical reactions or adhesives.
Rarely Used or Banned:
- 1,1,1,2 Tetrachoroethane – a possible carcinogen and cause of organ damage with long-term exposure, but rarely used in the US.
- Chlorofluorocarbons (CFCs) – used as a blowing agent to make the material foam. Pollution regulations (the Montreal Protocol) have largely restricted this and other toxic halogens in the US since the 1990s. Manufacturers can use other gases or pressurized foaming systems instead.
Sometimes products designed to protect us from one type of harm can have other ill effects. Fire barriers in some mattresses are such products. Though fire retardant, some contain toxic chemicals.
All mattresses sold in the United States must be able to withstand an open flame for a set period of time, per federal guidelines. This measure is designed to reduce mattress fires and improve consumer safety. But not all fire retardant materials are safe for humans to be around.
Because polyurethane foams are typically flammable, all must be treated with a chemical or a fire-resistant fabric. However, manufacturers are not required to disclose how they achieve fire resistance, so it may be not be easy to get this information from less transparent companies. Some of the chemicals used can be toxic.
- Brominated fire retardants/Polybrominated diphenyl ethers/PBDEs – refers to a group of substances that can be used to resist flames. The variations confirmed to be carcinogenic have been phased out in the US since 2005.
- Cotton treated with boric acid – possible organ toxicity.
- Chlorinated tris (TDCPP) – Possible neurotoxin, endocrine disruptor and carcinogen. Common flame retardant, but was recently the reason for a large crib mattress lawsuit in California.
- Wool – natural wool is a possible fire retardant, though usually not on memory foam beds.
- Modacrylic fiber – contains antimony oxide, a carcinogen.
- Melamine resin – contains formaldehyde.
- Decabromodiphenyl Oxide – hair loss, neurological effects, possible carcinogen.
- Kevlar – strong fibers, not natural but non-toxic.
- Alessandra fabric – wrapped fiberglass fibers, can be safe but may contain modacrylic fiber.
- Rayon treated with silica – non toxic, rayon is derived from bamboo pulp and silica from glass/sand.
The alarming toxicity of these chemicals in the fire barriers and other materials has prompted some new thinking on flame retardants.
“Instead of adding new fire retardant chemicals that ultimately may be shown to cause health problems, we should be asking whether we need to use these chemicals or if there are other ways to achieve equivalent fire safety, so many of the chemicals we have banned in the past were flame retardants—think about asbestos, polychlorinated biphenyls, polybrominated biphenyls, tris(2,3-dibromopropyl) phosphate, PBDEs—[and] they all ended up in the environment and in people. We need to think carefully about adding these sorts of chemicals to consumer products before there is adequate health information,” says Arlene Blum, a biophysical chemist and visiting scholar at the University of California, Berkeley.
What are the risks of VOCs and Off-Gassing?
The most hyped danger surrounding mattresses made of memory foam remains “VOCs” and “off-gassing”. The two terms refer to the same phenomenon of chemicals breaking down and dispersing into the air, which some have attributed to allergic reactions, breathing issues and toxin buildup. Memory foam and all polyurethane-containing and otherwise manufactured products can have a “new” odor, usually most noticeable the first few weeks
The term VOCs is short for volatile organic compounds. VOCs are called such because they are unstable and break down or degrade at room temperature, releasing odors as they do. You are already familiar with VOCs and their odors if you have ever smelled fresh paint, new cars, new furniture, some new clothes, and hundreds of other household and industrial products.
Low-level VOCs are difficult for researchers to study and assess due to their ubiquity and the time frame that would be required to assess effects (it is also impossible to isolate VOCs and their potential effects from every other item we encounter). Alone, their impact ranges from safe to toxic according to MSDS. Several are no more significant than an odor, and even humans and plants release types of VOCs as a part of biological processes.
However, some sources (some of which can be in memory foam like toluene, benzene and formaldehyde) have been associated with respiratory irritation, throat irritation, forgetfulness, feeling dizzy or developing a headache, and repeated exposure can lead to sensitization or allergic reactions (this is typically associated with workplace exposure however, according to the EPA).
Almost always, VOC hazards are higher in the raw materials used to create stable products like foams than in the finished product itself. As with memory foam, once the chemical components are combined into a stabilized product, the VOC release is minimized. Unreacted polymers and other components like glues and fire retardants can pose lingering odors and strong scents as well, though.
Not all foams are the same, however. Plant-based memory foams, like those from Amerisleep, give off fewer VOCs than mattresses made from synthetic foams.
How Do You Know if You’ll Be Affected?
Out of the many consumers who have bought memory foam beds, a very small portion seem to experience allergic-type reactions. There are some reports online of people experiencing nose, throat or eye irritation, asthma irritation, or nausea which they attribute to mattress odors. These reviews are in the minority compared to the thousands who have owned memory foam without incident over the past 25 years. According to Sleep Like The Dead’s research, odors cause less than 2% of people overall to return these mattresses.
Although different brands can vary on odor, beware if a company is pitching you “no VOC or VOC free” memory foam, as that is not a plausible product given how memory foam is made. A memory foam can be “low VOC” or “free of toxic VOCs”, but as we’ve mentioned before, almost every organic product has odorous properties that are “VOCs”.
In fact, the Federal Trade Commission recently sued and fined a few companies making the VOC-free claim that could not back it up including Essentia, Relief-Mart/Temp-Flow, and Ecobaby Organics.
The polyurethane used in memory foam beds is the same foam used in most household furniture (like sofas, recliners, and other items with foam). Almost all innerspring mattresses also have layers of polyurethane, and similar fire-barrier materials as well. If you experience an issue with other polyurethane containing items (like spring mattresses) or have reactions to odors from paint or new furniture, you may experience an issue with high-VOC memory foam as well.
If this is a concern for you, we recommend looking into natural latex mattresses which have no polyurethane foam. However, if you have no prior issues with sensitivity, than memory foam should not pose any major discomfort or health threat to you.
How Do Memory Foam Mattress Brands Compare?
Here is an example of how leading brands compare on complaints of odor, from our past article on choosing a memory foam mattress and from SleepLikeTheDead.com (listed alphabetically):
|Brand||Memory Foam Type||Density||Reviewers Complaining of Odor||Overall Satisfaction|
|Sealy Optimum||Traditional||3.7-4.0 lbs||7%||82%|
|Serta iComfort||Traditional||3.0-5.0 lbs||6%||83%|
|Simmons Comforpedic||Traditional||2.5-5.5 lbs||6%||82%|
Choosing a Safe Memory Foam Mattress
As we previously explained, studying the effects or risks of potential VOC exposure from memory foam is a difficult task, so there is little specific research, and none showing that memory foam is toxic or unsafe. The Polyurethane Foam Association, an industry group, as well as the Environmental Protection Agency both say that finished memory foam is inert and does not represent a health hazard.According to the EPA’s review of MDI and TDI, “Completely cured products are fully reacted and therefore are considered to be inert and non-toxic.”
A 2011 study from the Agency for Toxic Substances and Disease Registry (ATSDR) concluded, “We did not find a scientific connection between respiratory problems and exposure to TDI.” The American Chemistry Council also says that “Many polyurethane products are completely cured and therefore considered “inert” before they are sold, such as mattresses, pillows, furniture cushions, […].”
Once the polyols and isocyanates have reacted, they are chemically inert (no longer volatile) and no longer pose the dangers that individual components may. Polyurethane manufacturers in the United States are carefully regulated regarding ingredients and pollution, and the US and EU have banned the most hazardous chemicals and additives in the past 10 years. Residual concerns for choosing a safe bed of memory foam would include off-gassing odors and chemicals in adhesives and fire-proofing methods.
In order to choose the healthiest possible memory foam bed, here are few things you could check for when shopping around:
- Find out if a the foam is plant-based or made from petroleum. Plant-based foams have fewer synthetic materials in them and emit fewer VOCs.
- Ask if the foam was made with MDI or TDI, as MDI is known to be safer.
- Ask what kind of blowing agents are used; halogen gases CFCs/HFCs contribute to air pollution. Variable pressure foaming is a newer technique that negates the need for chemical blowing agents.
- See what the memory foam is made of. Blends that have a portion made with plant-based materials (20%+) have less petroleum content and thus less propensity to off-gas.
- Ask how the mattress achieves anti-flammability standards. Rayon treated silica and kevlar fabrics (not just seams) appear to be the safest options for reducing chemicals.
- See if there are any testing standards applicable to the mattress. Oeko-tex and Certipur require a minimum level of VOCs and product safety.
- Know that high-density foams have a greater amount of polymers, and thus are more likely to have stronger odors.
- Ask where the actual memory foam and poly foam layers are manufactured. If it is in the US or EU, they are made under stricter regulations than some imported foams and could be a safer option.
While ideally manufacturers would be open about product ingredients, due to tough competition and trade standards many brands may not disclose the information, and many salespeople may be uniformed. You can research online or contact companies directly if salespeople are unsure or don’t offer satisfactory answers.
The other way you can check on the safety of a mattress is to read reviews online and check the consumer product safety commission records. If a high percentage of reviewers mention strong odors or side effects, then the mattress may have a higher proportion of VOC content. If they just mention a light non-bothersome smell, or no smell, than the VOC content is likely lower. Keep in mind that smell is highly subjective, however, if a very large number of people report physical effects like sinus irritation than you may want to steer clear if this is a concern for you.
Minimizing Memory Foam Mattress Odors
To minimize any potential odors or discomfort, you can also follow a few guidelines after buying a memory foam bed. The best way to reduce odors is to unpack the mattress and remove all plastics as soon as you receive it. If you cannot air out your bedroom very well and the mattress has a strong smell, you may wish to set it in a garage or arable room for a few days with plenty of circulating air and ventilation. If the mattress cover is removable, take it off or unzip it to allow the foam to breathe. Don’t move the mattress into your bedroom until the odor has dissipated enough to no longer bother you.
Memory foam remains the highest rated mattress category overall in terms of owner satisfaction due to advantages like the ability to contour to sleepers, pressure point relief and support for natural alignment. Although concerns about household chemicals and toxic ingredients are valid, when it comes to today’s mattresses, they are largely unsubstantiated. There is no research available that says memory foam is unsafe, and authorities like the EPA and ACC concur that finished polyurethane foam is non-toxic.
As a consumer, you can protect yourself and select a safe, healthier memory foam mattress by understanding the basic science behind memory foam, knowing what questions to ask retailers, and by knowing what ingredients (and claims) to avoid. Your bedroom needs to be a safe place, so keep an eye on what you put in it.