Do you know what is in your mattress? Between a secretive manufacturing industry and increasing interest in chemical free products, more and more consumers are curious about what goes in to mattresses. We researched the major mattress types and materials commonly found in beds and compiled the information in this guide for easy reference. The truth about what is in your mattress may surprise or startle you, depending on the mattress type. Some types of beds contain more chemicals than others, and some brands may also use cheaper fillers to reduce production costs. Knowing what is in a mattress can critical for comparing beds when shopping, getting a good value and for peace of mind.
What’s In Your Mattress?
Mattresses have been made from a large number of materials over time, ranging from goat skin waterbeds to hay and cotton.Today’s mattresses tend be more complex, with all types of foams and fabrics. Many brands also come up with a variety of fancy trade names for materials making it even more difficult to figure out exactly what is in the bed. Our overview of common mattress types looks at what you are most likely to find within, then explains what the various materials are composed of.
Materials Common in All Mattress Types
Some materials are used broadly across different mattress types, and can be found in a majority of beds. We begin by explaining these common ingredients and then describe mattress types.
Polyurethane foam is found in wide a variety of products within the home, from mattresses to chair cushions. It is manufactured using a petroleum base, and can be a major source of pollution (though some manufacturers are improving with zero-emissions production processes). As with other petroleum or chemical based products, there are concerns regarding VOCs or volatile organic compounds, that can produce a strong chemical odor (see memory foam section below for more details).
Rebonded foam is the multi-colored pressed type of foam often found in carpet padding. It is made of shredded leftovers of various types of foam which are then bound together using a binder (glue or adhesive), cured and used in a variety of products, including mattresses. The adhesives used in bonded foams can be of concern for some, rebonded foam may be less durable than new foam.
- Polyester batting (fiber fill, quilt filling etc) is often used as a filling in mattress pillowtops, and polyester fabrics are often used in mattress covers (blended with other fibers or polymers). Polyester is a type of plastic made from petroleum-derived polymers. Though the end product is fairly inert, it can contain residues of the reactive/toxic chemicals used in production, is not breathable, is highly-flammable, and is not environmentally-friendly to produce.
Wool is derived naturally from sheep and is used in some higher-end mattresses for padding, temperature regulation or flame protection. Wool absorbs moisture and proves breathable. Non-organic wool may be treated with chemicals and pesticides. Wool may be considered sustainable and eco-friendly since it can be harvested without harm to the animal.
Cotton is used both inside mattresses and in mattress cover fabrics. Cotton is a very breathable and durable material that feels pleasant and is naturally dust-mite resistant. However, non-organic cotton is one of the dirtiest crops grown, and is often heavily saturated with pesticides and chemically treated with bleach and other additives. Organic cotton fabrics will not have chemical pesticides or dyes and provide a healthier option.
Adhesives are used by many manufacturers to bond mattress layers, bond mattress components, and finish seams. They are commonly found in all types of mattresses. However, nearly all adhesives contain potentially hazardous chemicals that can contribute to chemical off-gassing, and some of which have been linked to cancer and hormone disruption. A solvent based adhesive can have nearly 50 different toxic chemicals that may include acetone, benzene, formaldehyde, ethylene chloride, CFCs, halogens and other VOCs. Water-based adhesives have reduce potency compared to solvent-based adhesives and are considered more environmentally-friendly, but still contain chemicals.
Flame retardants are going to be present in pretty much every mattress sold in the US due to flammability laws. Manufacturers can achieve fire resistance with chemical additives or fabric barriers, and they are not required to disclose what they use in order to protect “trade secrets”. The most toxic of these, PBDEs, have been voluntarily discontinued by US and EU manufacturers though other similar brominated retardants are still in use. Another chemical of concern is chlorinated tris, which has been linked with cancer and fertility side effects (and was recently found in children’s mattresses imported from China, though it is banned in children’s pajamas and has been eliminated by some US manufacturers). Other common chemical flame retardants include antimony and halogens. Less hazardous materials like wool, rayon and other specially designed fibers, and boron can also be used to achieve flame resistance.
Coil and Innerspring Mattresses
- Metal coils
- Rebonded foam
- Polyester fiber and fabric
- Cotton fiber and fabric
- Polyurethane foam
- May also contain latex or memory foam layers
Coil and spring mattresses utilize metal coils as the primary support component of the mattress. These coils, usually steel, can come in a variety of formats, such as independent bonnell or offset coils, continuous coils, and pocketed coils. Because sleeping on metal springs would not feel so great, spring mattresses have layers of padding on top. Many companies use rebonded foam layers to reduce costs, often combined with various polyurethane foam layers. Pillowtop mattresses may incorporate softer polyurethane foams as well as polyester or cotton fiber filling. Many modern innerspring beds also incorporate memory foam and latex layers in their luxury lines for added pressure relief and comfort.
Consumer Mattress Reports Top Picks for Healthy Innerspring Mattresses
- OMI OrganiPedic (queens $2595-$3195) – Natural and organic cotton fabric and batting with latex foam options over metal springs.
- RoyalPedic Organic Collection (queens $2875-$4107) – Organic cotton padding and fabric with wool wrap and latex options over metal springs.
Memory Foam Mattresses
- Memory foam
- Polyurethane foam
- Cotton/polyester blends or rayon
Memory foam mattresses contain a specialized type of polyurethane foam designed to have visco-elastic properties, meaning it is viscous and can contour to the sleeper, but also returns to its original shape afterwards. Like polyurethane, it is composed of petroleum-derived polymers. In addition to the chemicals in adhesives, memory foams can contain a few other toxic chemicals (ranked in order of greatest concern, based on information from the EPA website):
- 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 and from nearby plants.
- Vinilideine chloride – eye and respiratory irritation, possible carcinogen, organ damage. Primary hazard is during manufacturing.
- Methyl benzene / Toluene – inhalation can affect nervous system.
- Dimethylformamide – organ damage possible, and possible carcinogen, though primary risk is during manufacturing.
- 1,1,1,2 Tetrachoroethane – a possible carcinogen and cause of organ damage with long-term exposure, but rarely used in the US.
- Acetone – toxic when inhaled in large amounts, but limited effects with low exposure.
For those concerned about chemicals, consider looking for CertiPUR certified foams and inquire about the adhesives and fire-barriers used. CertiPUR certified memory foam has undergone independent testing to ensure low VOC levels and absence of PBDEs, CFCs, heavy metals, formaldehyde, and banned pthalates. Many US manufacturers have also began using barrier fabrics on memory foam mattresses for fire resistance as opposed to the chemical retardants.
Newer Memory Foams: Gel memory foams have the same basic formulation of polyurethane foams, but either have gel liquid or gel beads mixed in during production, or gel added after production. As for what the gel or “phase change material” is actually made of, we had little luck finding out other than allusions to ‘prepolymers’. There are also newer generations of memory foam and poly foams designed to be more sleeper- and eco-friendly, accomplished by reducing potentially harmful VOCs and/or using a portion of plant-based oils in lieu of petro-oils, often called soy or plant-based memory foam. We discuss the differences between the main memory foam types in greater detail in our Memory Foam Mattress Checklist post.
Consumer Mattress Reports Top Picks for Healthy Memory Foam Mattresses
- Amerisleep (queens $849-$1899) – Plant-based memory foam with bamboo and cotton blend covers and natural Green Guard fire barrier. CertiPUR certified foams.
- Keetsa (queens $1049-$1679) – Plant-based memory foam with cotton or hemp covers and non-toxic fire barrier. CertiPUR certified foams.
- Natural latex
- Synthetic latex
- Cotton, Cotton blends
Latex mattresses can contain either natural latex material, synthetic latex material, or a blend of the two. 100% natural latex is harvested from rubber trees via a method similar to syrup tapping. The liquid is combined with ammonia and antioxidants for preservation. It is then whipped into a froth with a few additives including a foaming agent (soap/plasticizer), a gelling agent (SSF in Dunlop/CO2 in Talalay), and curing agent (sulfur). It is then molded, heated and cured (the Talalay process also adds a few other steps). The additives typically evaporate during the foaming process, and the finished foam is washed as well.
Synthetic latex was initially developed during WWII as natural latex supplies dwindled. It is manufactured in the laboratory as styrene-butadiene rubber, via petroleum-based ingredients. Individually, styrene is regarded as toxic, mutagenic, and possibly carcinogenic, while butadiene is a known carcinogen, suspected teratogen, and irritates mucus membranes. SBR can also be blended with polyurethane (see above). Finished synthetic latex foam is less hazardous, but is more likely to have a strong odor than natural latex. Blended latex beds contain a ratio of both natural and synthetic latex liquid. Blended beds can be referred to as ‘natural latex’ if they contain at least 30% natural latex material.
The makeup of a true latex mattress consists of a latex foam core and possibly additional latex foam layers. There are “hybrid” latex mattresses available the have latex over springs or polyurethane foam as well. In all-latex beds, some manufacturers do not glue internal layers together, which eliminates adhesives in the mattress. Because natural latex is not highly flammable, latex manufacturers usually use fabric fire socks or incorporate wool into the surrounding covers to meet codes. Some latex brands have Oeko-Tex 100 certification, which test mattresses for harmful chemicals and is one of the most stringent product safety certifications available.
Consumer Mattress Reports Top Picks for Healthy Latex Mattresses
- Astrabeds (queens $1799-$2999) – 100% natural, organic Dunlop latex mattresses with unglued layers, organic cotton covers and organic wool fire barriers. GOLS-certified latex foam, OCS/GOTS-certified organic cotton and Eco-Institute certified for VOCs.
- Savvy Rest (queens $2119-$3949) – 100% Natural Talalay and Dunlop mattresses with wool fire barrier and organic cotton cover. Oeko-Tex 100 certified, OTCO/GOTS-certified organic cotton and wool.
Waterbeds are primarily composed of a bladder, almost always made of PVC or a PVC relative. PVC, aka vinyl or polyvinyl chloride, is a common plastic made of vinyl chloride mixed polymerization initiators and pthalate plasticizers. The phthalates and chemicals used in PVC are subject to leaching and outgassing, and have been associated with environmental pollution and possible adverse health effects, as well as occupational cancers. Some also have polyester or other synthetic fiber layers within the bladder to reduce motion.
Consumer Mattress Reports Top Picks for Healthy Waterbeds
- All waterbeds use fairly similar materials, with primary differences being vinyl thickness and seam construction. Two longstanding and well-known brands are Innomax and Boyd, whose hardside mattresses range from $99-$400.
Mattresses, like many modern products, can contain an array of complex materials that can easily be overwhelming. Nearly every bed produced today will have chemical origins in some form or another. If you are concerned about “chemicals” in your mattress or maintaining a healthy home, you don’t need to become an expert chemist, just use common sense. Certain independent certifying bodies like Oeko-Tex and CertiPUR can help make shopping easier by identifying options that meet safety standards, and others like GOTS identify organic fabrics that are free of pesticides. Manufacturers should also be open about what is their beds so you can easily compare value and avoid materials of concern to you. As consumers become more and more curious about product ingredients and health, this information is gradually becoming easier to find, though several of the “big names” remain reluctant to divulge ingredients. Getting a good deal on a mattress requires informed shopping, and knowing the basics of mattress materials is a good place to start to ensure your next bed meets your expectations.