by Green Building Supply's Joel Hirshberg
February 4, 2021
Average reading time: 18 minutes

Healthy Building Network reveals 44 toxic chemicals

If you have carpeting in your home, you probably have no idea what you and your family are walking on or breathing every day. Don’t feel bad! Few people do—until now, thanks to a report by the Healthy Building Network (HBN).

Through their excellent research, you’ll learn what you’ve always wanted to know and what few carpet manufacturers have wanted to tell you. That is, in part, because they didn’t have to. Federal and state regulations, as well as third-party certification organizations, don’t restrict many of these chemicals. Due to the lack of transparency in the carpet industry, it’s next to impossible to pinpoint all the materials used in every type of carpet. Consequently, consumers are left in the dark and must trust salespeople and product reviews for guidance as to which carpets are the safest.

According to HBN:

“Neither manufacturers, nor third party organizations that certify carpet products, provide a full accounting of these substances. Many carpets, carpet pad, and carpet adhesives have obtained product certifications that assert certain attributes, like being free of “Red List” chemicals or VOCs; however, the standards upon which the certifications are based do not consider most of the 44 priority toxic substances we identified that are used in carpet.”

But now, HBN has uncovered the sources of the strong chemical odors that we’ve all encountered when we walked into a newly carpeted room. This list includes numerous known and suspected carcinogens such as formaldehyde and benzene as well as countless other volatile organic compounds (VOCs). Now that many of us are spending the majority of time indoors due to the COVID-19 pandemic, it’s imperative to understand the impact of carpet on our indoor air quality, health, and wellbeing.

In their original study, the Consumer Product Safety Commission identified at least 30 chemicals released by synthetic carpets. (“Carpets and Rugs Business Guidance.” United States Consumer Product Safety Commission. Accessed October 5, 2017) This new study by HBN has discovered some 44 hazardous chemicals present in most synthetic carpet. Not every carpet contains all 44, of course, but each carpet has some of them and many carry most of them. See the end of this document to see all 44.

Modern carpeting is made primarily from synthetic-based fibers such as nylon, polyester, polypropylene (olefin), recycled PET (polyethylene terephthalate), and the newest fiber Triexta (aka Smartstrand, Sorona, and PTT—all of which are modified versions of polyester). While all of these are derived from petroleum as their main ingredient, they are often treated with additional chemicals that provide stain proofing, moth protection, and fire resistance.

To prevent mold and mildew, carpets are further treated with additional chemical fungicides and pesticides. Fibers are then attached (tufted) into a backing crafted mainly of polypropylene with the help of synthetic rubber, polyurethane, polyvinyl chloride, or ethylene-vinyl acetate. Many of these synthetic chemicals have been found to outgas chemicals for many months or even years. They’ve been associated with symptoms such as eye, ear, nose, and throat irritations; heachaches; skin irritation; coughing or shortness of breath, and fatigue. The impact on children and domestic pets is even more acute because they spend much of their time in direct contact and within close proximity to carpet.

We believe consumers have a right to know what they are buying. You may find the attached report helpful in educating you about carpeting you have already purchased or may purchase in the future. We believe that informed consumers who vote with their dollars are the best drivers of market change.

Below is a summary of the general categories of chemicals. For those wanting to see all 44 presented technically, refer to the end of this article.

1. Stain repellent treatments contain short-chain per and poly-fluoroalkyl substances (PFAS). These are potent developmental and reproductive toxicants that can be inhaled or ingested throughout the lifecycle of production, use, and disposal.
2. Antimicrobial preservatives protect plastic ingredients from biological degradation, including highly toxic triclosan, an endocrine disruptor, and formaldehyde, a known carcinogen. (California Prop 65 )
3. Isocyanates, the main ingredient of polyurethane in the carpet backing, is a highly potent respiratory hazard that is not recyclable.
4. Polyvinyl chloride (PVC), widely used as a binder in carpet tile and carpet backing contains heavy metal stabilizers such as organotins and phthalate plasticizers. These are well-known toxicants to humans and aquatic life and can produce cancer, in addition to causing developmental and reproductive harm.
   Scientists are finding alarming correlations between phthalates and asthma and human neurological diseases. Even though many manufacturers are phasing out phthalates, they still use PVC, whose production inherently relies on toxic inputs and produces toxic byproducts. These include chlorine, chloroform, and highly carcinogenic dioxins, vinyl-chloride monomers, and ozone-depleting chemicals like carbon tetrachloride.
5. Flame retardants, used in polyurethane and latex backings as well as some specialty fibers. Some of these flame retardants are halogenated, which means they contain chlorine or bromine. These are linked to hyperactivity, learning disabilities, reproductive harm, and cancer. The common replacements are not much better as they contain organophosphates, which are linked to endocrine disruption and infertility.
   Flame retardants are emitted from carpet into dust that becomes airborne during use as well as from operations that recycle and dispose of carpet waste. Unfortunately, these chemicals persist and bioaccumulate up the food chain. They are also found in bonded carpet padding.
6. Fly ash, a byproduct of coal-fired power plants, is widely used as filler in carpet tile. While this is considered “recycled content” and contributes to LEED points, it is nonetheless unhealthy. Pollution control devices on power plants transfer mercury, a potential neurotoxicant, from air emissions into fly ash. Astonishingly, some carpet, by weight, is 40 percent fly ash.
7. Adhesives, such as bisphenol A and nonylphenol ethoxylates, have both been found to be neurotoxicants that cause endocrine disruption.

It’s not all gloom and doom. Industry-wide, DuPont, among others, has begun replacing petroleum with corn glucose by up to 37%, Shaw has stopped using fly ash as a filler, and many, but not all, manufacturers have phased out phthalates.

While we are all for recycling synthetic carpet and closing the environmental loop from cradle to grave, it does not solve the real problems related to toxic exposures during the process of manufacturing, installation, use and disposal. One of the major goals of recycling is to prevent these toxins from entering landfills and bioaccumulating for thousands of years and eventually ending up in our food chain. While this is a laudable goal, recycling in no way guarantees that hazardous air pollutants won’t emit all over again.

In the opinions of HBN and Green Building Supply, the potential environmental and human health impacts of these toxins should be fully disclosed and assessed long before ever entering the marketplace. When safer, biodegradable, and sustainable alternatives exist, there is no reason for carpet manufacturers to use toxic substances. Nor is there any reason for consumers to buy them, for third parties to certify them, or for government regulators to allow them on the market.

There are several sustainable, eco-friendly carpet options that can minimize indoor pollution and mitigate health problems caused by toxic carpets. Durable, stylish, and often less expensive than conventional floors and carpets, these sustainable options provide a responsible and healthier way to enhance your home.

These natural alternatives include 100% wool, sisal, jute, cotton, and silk. Most of these contain either reduced or no hazardous chemicals at all. Most wool carpeting, for example, will outlast synthetic carpets by a factor of 3 to 1. They also have a much lower carbon footprint, are fully biodegradable and perform as good or better than their toxic counterparts.

At Green Building Supply, your health and safety always have been and always will be our top priority. That’s why we offer several brands of wool carpeting made with the purest natural ingredients. Now you know why we don’t sell synthetic carpet. For more info on our wool carpet, click here.

Below is a chart of all 44 chemicals found in synthetic carpet. Again, not all are in every carpet.

Note: PBT = Persistent, Bioaccumulative Toxicant (PBT)

¹ “Work Plan Implementation: Perfluoroalkyl and Polyfluoroalkyl Substances (PFASs) in Carpets, Rugs, Indoor Upholstered Furniture, and Their Care and Treatment Products.” Safer Consumer Products Branch, CA Department of Toxic Substances Control, November 15, 2016. https:// www.dtsc.ca.gov/GetInvolved/ReviewPanel/upload/DTSC-Work-Plan-Implementation-Perfluoroalkyl-and-Polyfluoroalkyl-Substances-inCarpets-Rugs-Upholstered-Furniture-and-Their-Care-and-Treatment-Products-11-15-16.pdf.

² Perfluorinated Chemicals (PFCs).” National Institute of Environmental Health Sciences, July 2016. https://www.niehs.nih.gov/health/materials/ perflourinated_chemicals_508.pdf.

³ “Methylenediphenyl Diisocyanate.” Haz-Map. Accessed October 10, 2017. https://hazmap.nlm.nih.gov/category-details?id=13260&table=cop ytblagents.

(For the complete white paper, read the HBN article here which includes an in-depth explanation of all of 44 chemicals included in these seven categories.)

Questions, comments, or suggestions can be sent to [email protected]