Foam Guide

Polyurethane Foam

Is polyurethane foam toxic?

Yes, most likely. While I’m tempted to say with certainty that all PU foam is toxic, I can’t quite say 100% yes because of the lack of transparency in the ever-changing ingredients lists. The lists are considered a proprietary secret, so that different companies can create different textures and types of foam without being copied. The little that we do know about the ingredients is unflattering when they are revealed, and they keep changing in reaction to updated health and environmental policy rules. For example, the blowing agents used in foam manufacturing changed in 2020 from hydrofluorocarbons (HFCs) to hydrofluoroolefins (HFOs) because HFCs were causing environmental harm (now, the new HFOs may be banned because they qualify as a forever chemical in some states). The main catalyst used in foam, stannous octoate, was declared a reprotoxic 1B chemical that may damage unborn children (fetuses) and some (not all) foam started being made without it in 2023. Flame retardants are no longer allowed in some foam in some states as we’ve learned how harmful they are to the human body and the environment. The level of VOCs foam emits is also lower now than it used to be, because consumers were bothered by the fact that foam off-gasses toluene, xylene, and acetone, among many other compounds, and the industry adjusted to make their foams less smelly. While all of the above certainly qualifies foam, in my opinion, as 100% yes, toxic — if you choose foam made without any of these things, is it still toxic? My hunch is: probably! There are very likely more unsavory chemicals being used in it now that we may discover and ban in the future. But, without knowing what they are, and how they interact with the body, I can’t say for sure. For this reason, I practice the Precautionary Principle with foam, and avoid it as often as I can.

What is polyurethane foam made of?

Polyurethane (PU) foam, the type of foam in mattresses, couch cushions, and insulation spray, is made of 2 main ingredients, polyols and isocyanates. Many more ingredients are added to make foam processing easier in the factory, and to make the foam feel, look, and perform in a certain way when it’s finished. Surfactants, blowing agents, curatives, and catalysts are four main categories that are added to the basic foam mixture, to puff it up into a perfectly bouncy, rectangular shape that slips off the mold in the factory easily. Other chemicals are added to make the foam either softer, “cooling,” squishier (like memory foam), anti-bacterial, a different color, etcetera.

What are polyols and isocyanates?

Polyols are pretty boring; they are little molecules that usually come from petroleum, but can come from plant-based sources now, too. Other than the fact that they require petroleum refineries, they won’t directly impact your health from being in a piece of foam.

Isocyanates are more interesting from a health perspective— these are well known to cause asthma, lung damage, and in severe cases, fatal reactions (you can read more here) if you’re exposed to these without protection, like if you’re working in a foam factory, or spraying foam insulation. When polyols and isocyanates are mixed together (see a 60 second video here), they react, and create a somewhat hard, straightforward piece of foam.

Should I worry about isocyanate exposure?

Probably not, if it’s just the isocyanates in mattress or couch cushion foam. Even though isocyanates are known to be quite a toxic chemical on their own, if they are fully mixed together with polyols in just the right ratio, the mixture becomes cured, or chemically inert. If that’s a weird concept, you can think of it like water, which is 2 hydrogen molecules connected to an oxygen molecule. Hydrogen and oxygen, on their own, are very reactive. But, once they are combined (“cured”) together, they are inert— they can’t cause harm to you, and are simply water.

One possibility for toxicity is that polyols and isocyanates are not mixed in exactly the right ratio, and the unreacted isocyanates are able escape from foam and harm you. One 2012 research study assessed whether people sleeping on mattresses were exposed to unreacted isocyanates— but it was conducted by members of the Dow Chemical Company, the International Isocyanate Institute, and BASF Polyurethane (just click “Show More” under the list of authors.) The results were, surprisingly— no health effects! A 2015 study of 20 crib mattresses done through the University of Texas showed that many contained unreacted isocyanates (among other things). That’s it. I would love to see more, unbiased research on this.

Another possibility for isocyanate toxicity is if you’re using spray foam insulation. I don’t cover building materials on this website, but as you can see, spray foam is listed as the most toxic possibility for insulation here, partly because as you spray, you are exposed to isocyanates.

Does foam cause cancer?

Some of the ingredients in foams may contribute to cancer risk. Certain flame retardants, common in foam to make it less flammable, are linked to cancer. The Phillips Respironics brand announced a voluntary recall on their CPAP machines made with polyurethane foam in 2021, because the foam contained diethylene glycol, toluene di-isocyanate isomers, and toluene diamine isomers that are associated with possible carcinogenic effects.

I’ve read studies that say that the levels of VOCs and other chemicals in foam are so low, they won’t harm you.

I think this is partially true, but this statement is more valid for 1 foam item over a short period of time, rather than real-life accumulated exposures to many foam items. When this is used to defend a foam mattress, you are likely spending more time on foam than just sleeping— if you drive to work in your car, the seats are padded with foam. Your office chair and even keyboard rest may have foam in them. If you go to the gym or sit in the dentist’s chair during your lunch break, you’ll be exposed to more foam. The couch you sit on before bed has foam in it. And so on. Foam is everywhere in the US! Over the course of your life, your foam exposure adds up, and because many of the chemicals in it (like flame retardants) are bioaccumulative or affect you at even low levels (like BPA, an endocrine disruptor), I think it is worth avoiding this logic when possible.

How do foam chemicals get into my body?

There are two ways chemicals leave the foam, and three ways they get into your body:

The two ways chemicals leave the foam are into the air and into dust. Polyurethane foam (including memory foam) is made with 2 chemicals as the main building blocks, polyols and isocyanates (see more above). They bond together very tightly, so other additives in foam (like flame retardants and other propriety chemical ingredients) are integrated, but only temporarily— they’re not bonded together tightly, and over time, as foam degrades via friction, they fall out. If they’re lightweight, they can be suspended in dust in the air, and if they’re heavier (like flame retardants are) they settle into dust on the ground. The other way chemicals get out of mattresses is by being volatile— so, a VOC or odor— these are lighter than air. The “new mattress” smell comes from foam and the adhesives used to keep the layers together, and they can off-gas VOCs for quite some time.

The three ways these chemicals get into your body are through inhalation, ingestion, and absorption. You inhale and ingest VOCs and lightweight chemicals suspended in the air — they come in through your breathing passages and are swallowed, as well. You ingest about 50mg of dust daily (children ingest 100mg daily!) by touching dusty surfaces and hand-to-mouth contact. Finally, flame retardants and other chemicals are very small and as they make their way out of mattresses, can pass through skin and be dermally absorbed.

How long does foam off-gas for?

At least a year, though the amount decreases over time, overall. Off-gassing will speed up with heat and humidity.

What is CertiPUR foam?

CertiPUR foam is polyurethane foam, but it’s hard to know what is actually in it. CertiPUR prohibits the use of formaldehyde, heavy metals, some (but not all) phthalates, and some (but not all) flame retardants.

Is CertiPUR foam actually non-toxic?

No, probably not. While it’s certainly a good thing that stannous octoate (which can harm unborn children) is now banned in foams carrying the CertiPUR logo, it was still permitted in CertiPUR foams until 2023. In other words, people buying CertiPUR foam until recently were misled into thinking it was “pure” and safe. I understand that not everything can be completely pure, and that it is practical to allow small amounts of harmful substances in things for a period of time, because of the major changes to industry that a rapid ban would cause — OEKO TEX does a great job of this, for example — you can see that over the years, they are continually lowering the acceptable amount of BPA allowed in products, and in 2025, the level is almost down to zero. If they had demanded that instantly, it wouldn’t have encouraged more companies to slowly change over time. However! CertiPUR doesn’t disclose what is on their list, or what levels are acceptable, like OEKO TEX does. It is almost completely opaque. All we know is that some things are banned, but not all of them, nor in what amounts. The surprise of stannous octoate also shows that their stance on health is conservative and reactionary, rather than health-centered and forward-thinking. From what I understand, the lack of disclosure is potentially partly because CertiPUR is not a third-party certification. It is a second-party certification, meaning the synthetic foam industry itself created the standards and chose a lab to test its products for them.

Is memory foam toxic?

Yes, most likely. Memory foam is made of the same things as polyurethane foam, described above, but with various chemical additives to create its signature texture.

Is GreenGuard GOLD foam non-toxic?

No, but it does mean it will off-gas under a certain level. To meet the standard GreenGuard level, VOCs must be less than 500 ug/m3. To meet the elevated GreenGuard GOLD level, VOCs must be less than 220 ug/m3. A GreenGuard certification does not mean it is healthy, and it does not mean there are no VOCs off-gassing from the product. Sometimes I see companies say “It’s GreenGuard so it’s healthy!” which is simply not true. There are many harmful chemicals in foam that don’t off-gas as VOCs. That said, it is still a useful certification when choosing between a standard foam mattress that might off-gas a lot, and one with GreenGuard certification. It’s still a step in the right direction.

What is MADE SAFE foam?

MADE SAFE certification has 6,500 chemicals on their banned/restricted list, which is based on a combination of European Union standards, the Red List, and other international agencies setting standards for products better for human health. While this certainly sounds impressive, I have become a bit more wary of it as I’ve learned more. It applies to many consumer goods, including foam, but also cleaning products and others. It’s easier to get to “6,500 banned substances” if you’re including the many chemicals potentially present in cleaning liquids and other things, too.

More importantly, the list isn’t a full ban, and we don’t know what’s on the list. They state that “Some substances may have category specific allowances or technically unavoidable content, in which case either additional testing or threshold requirements may apply” here, but these limits aren’t published, nor is the list itself.

While I’m sure that a MADE SAFE product is safer than one without testing, I now rate it as “OK” until the limits and list are more transparent.

What is OEKO TEX foam?

OEKO TEX usually applies to fabric, but it can also include foam if it’s part of a finished textile-containing product. An OEKO TEX certified foam means that the final product has been tested and verified to have very low levels of certain harmful chemicals. It applies to the finished product only, so they don’t require disclosure of every single ingredient along the way. OEKO TEX can be applied to organic, natural and synthetic products, so a pure latex foam mattress, or even a polyurethane foam mattress. You can see the OEKO TEX limits, which are updated annually, here.

Does OEKO TEX foam have flame retardants in it?

No, OEKO TEX foam doesn’t have chemical flame retardants in it. It may have safe, non-chemical flame retardants, like wool or graphite. That’s because OEKO TEX requires a company to apply for a special exception if they are going to use flame retardants in something— for example, firefighters’ uniforms are required to have flame retardants, but can still be OEKO TEX certified if they are otherwise healthy and meet their standards.

Why do you have OEKO TEX ranked lower than C2C and ecoINSTITUT?

C2C and ecoINSTITUT require full disclosure of every ingredient used throughout the whole process. OEKO TEX focuses on just the finished product.

Natural Rubber Latex Foam

What is latex?

Latex is the same thing as natural rubber. It comes from the Hevea brasiliensis tree. It is a milky white liquid that can be baked to form a springy, foam-like substance. It is often confused with synthetic (lab-made) latex, which is the chemical mixture styrene-butadiene. Confusing!

What is Dunlop vs Talalay latex?

Natural rubber latex is the starting material for both Dunlop and Talalay latex. Dunlop and Talalay are the names for two different methods of processing the latex.

What is Dunlop latex? How is Dunlop latex foam made?

First, the latex must be from an organic latex tree farm, grown without pesticides. The latex rubber “milk” from the tree is poured into a mold, mixed with Zinc, Sulfur, and soaps to make it a “gel,” then is baked into shape. It’s washed to remove impurities, and then is baked again to dry it out. This process has been used for about 100 years, and the result is a dense foam. To meet the the GOLS standard, it must be composed of at least 95% organic latex.

What is Talalay latex? How is Talalay latex foam made?

To make a less dense, softer, latex foam, the Talalay method was created in the 1940s. The natural rubber “milk” is poured into a mold, but only filled partway. At this point, processing agents are added to the mixture, and a vacuum seal is applied so that the foam puffs up and the air pockets are dispersed evenly. Then, it is flash-frozen with carbon dioxide to hold its shape, and baked. This process makes an airier foam than Dunlop, which is how it gets its softness.

Talalay latex isn’t organic, so cannot be GOLS certified. This can be OK, and truly natural Talalay is a fantastic choice compared to regular polyurethane foam. The only issue is that some manufacturers do not disclose what agents and additives are used. Unfortunately, and confusing to many, this can still be sold as “100% natural latex,” even with additives.

Unless they have third party certification! Look for ecoINSTITUT, or C2C Gold or Platinum, certification, which ensures that 100% of the ingredients have been disclosed and confirmed that they are safe for human health. If you are choosing a mattress made with Talalay, make sure the company states exactly where it is from, and if it has legitimate certifications like C2C or ecoINSTITUT.

Finally, because Talalay is less dense than Dunlop, a large single sheet (the size of a mattress, for example) is harder to achieve. Instead, several smaller pieces may be glued together. This can be avoided by mattresses that come in slabs that you stack yourself. Or, some brands will use non-toxic adhesives, even sometimes using liquid latex.

To sum it up, Talalay can sometimes be almost as healthy as Dunlop, but you have to make sure it was processed correctly, and that the company isn’t using it as a healthwashing technique.

What is GOLS certified latex?

GOLS, the Global Organic Latex Standard, is the gold standard 3rd party certification for organic rubber latex. Latex with the GOLS-certified organic label means 95% of the final product is organic latex, and also ensures that the processing stages (mixing, baking, etcetera) of the product are safe for human and ecological health. Only latex processed by the Dunlop method can be GOLS certified. To be sold as GOLS latex, the distributor must also be GOLS certified, ensuring that they didn’t add anything to the product after the latex was received and sent to customers. This can be an expensive certification, so you will see it more with large companies.

What is GOTS approved latex?

GOTS certifies textiles — so, fabrics and upholstery— not latex. But, GOTS will accept latex in “GOTS certified products” if it is either organic, organic-in-transition, or sustainable (see the fine print about this here.) This is sort of like having OEKO TEX certified polyurethane foam. So, while it’s legal for a company to advertise their “GOTS certified organic latex mattress” without also having organic certification for the latex itself— which makes up the bulk of the mattress— I think it’s a little deceptive considering “GOTS” looks so much like “GOLS.” GOTS is so well respected, and this may be a healthwashing tactic for customers not looking closely. Or (!), depending on how you look at it, it can also just be another nuanced shade of grey in the evolving natural foam landscape. While it’s not organic latex, it does help meet the rising demand for latex overall, and natural latex is still far better than polyurethane foam.

What is FSC-certified latex?

FSC, or the Forest Stewardship Council certification, is focused on responsible management of forests. For latex, it means that the trees the latex comes from meet forest management standards, indigenous people’s rights are respected when harvesting, and old growth forests are not disturbed. It’s a fantastic certification in terms of our environment and community, but FSC-certified latex can still be mixed with many other chemicals that harm your health, like styrene-butadiene rubber (synthetic rubber). I don’t consider it any healthier than standard for this reason.

What is C2C certified foam?

C2C is short for Cradle2Cradle. They certify products for material health (as well as for sustainability and equity.) A product can quality for bronze, silver, gold, or platinum status, depending on how many of the ingredients are disclosed, whether the product has low or very low VOC emissions, and several other chemical safety benchmarks. Even at the lowest level, bronze, no PFAS are allowed. See the details of each level here (expand the “Material Health” section).

For example, a mattress or pillow made with Talalay latex that has C2C Gold certification means that 100% of the ingredients its made with have been declared by the manufacturer, and then assessed by C2C to be verified safe for humans and the environment (no synthetic rubber has been added).

What is ecoINSTITUT foam?

ecoINSTITUT certifies polyurethane and latex mattresses, couch cushions, and other foam products. It requires that the foam makers disclose 100% of ingredients (this is probably why I’ve never seen a polyurethane foam mattress with this certification) and that any harmful substances are under very low percentages, including low VOC emissions. You can see their limits here.

Other Types of Foam

Is soy foam non toxic?

Yes, most likely. Soy-based foams contain, on average, 5% soy by weight. The remaining 95% is polyurethane foam. This is a classic example of healthwashing, and for now is true of all “bio-based foams”. If a mattress company can prove their foam is made with 100% soy or other plant oil, it would be healthier than PU foam.

Is EVA foam toxic? Is EVA foam non-toxic?

It falls somewhere in the middle. EVA (ethylene vinyl acetate) is used to make shower curtain fabric, and in that context, it’s surprisingly pretty non toxic, as found by various agencies including the International Agency for Research on Cancer (IARC), OSHA, or National Toxicology Program (NTP).

But of course, EVA foam is different; it’s a much thicker version of EVA fabric, and the main chemical people are concerned about is formamide, which is added to make it foam-like and soft. It’s not safe at high doses, and can be absorbed through the skin, inhaled, and ingested, potentially causing various problems. That said, an EVA foam with very low amounts of formamide, as confirmed by a third party, that has had a chance to off-gas, is still better than polyurethane foam or PVC because it doesn’t require phthalates to make it a soft and flexible, and it doesn’t require chlorine in its production. It’s still hard to know exactly what else may be in it, so choosing cork or natural rubber latex would be healthier options.