People pose on yoga mats

Yoga Mats Testing Reveals Greenwashing

Environmentally Friendly Labeling of Some Yoga Mats Disguises Actual Composition

Ann Arbor, MI, August 6, 2019 — Laboratory testing by the nonprofit organization Ecology Center found some yoga mats marketed as eco-friendly were made of materials that present environmental and human health hazards. For the study, the Ecology Center’s Healthy Stuff Lab tested eleven brands of yoga mats purchased by Consumers Advocate, an editorial and consumer review website.

View the complete Healthy Stuff report.

Findings include:

  • Yoga mats labeled PER, Polymer Environmental Resin, were made of vinyl (PVC), a material that causes the release of toxic and persistent chemicals during manufacture and disposal.

  • A yoga mat advertised as “organic jute and PER” was made mostly of PVC with a single layer of jute.

  • The yoga mats made of PVC contained the plasticizer DOTP, a substitute for phthalates that is likely safer but needs more research.

  • A yoga mat made of recycled wetsuits contained phthalates, a hazardous class of plasticizers.

"I had not heard of PER before. I was surprised when I learned it stands for 'polymer environmental resin,' a name that tells us nothing about its composition. It sounded like greenwashing, and our test results appear to confirm that," stated Gillian Miller, senior staff scientist at the Ecology Center.

Due to the eco-friendly marketing of these yoga mats, consumers may be misled to believe they are purchasing a product that does not negatively impact humans or our environment.

Charlie Cray, senior research specialist at Greenpeace, told Consumers Advocate, “There isn’t a yogi in the world that could twist themselves into a position that’s as crazy as a company does when it claims that any PVC product is eco-friendly. It is toxic from production to disposal; there’s dioxin, for example, associated with every stage of the process.”

According to marketing materials, PER is “eco-friendly” and “biodegradable.” But its PVC composition brings those claims into question. 

The test methods used to identify the major components of yoga mats were high-definition X-ray Fluorescence (XRF) and Fourier Transform Infrared Spectroscopy (FTIR).

Of the eleven yoga mats tested, three were largely PVC: Ajna Natural Jute, Aurorae Synergy 2-in-1, and GAIAM Premium Yoga Mat 6mm. Only the GAIAM mat, however, was labeled as PVC. The Ajna mat was labeled “organic jute and PER” and the Aurorae mat was labeled “PER.”

The term PER appears to indicate PVC that does not contain phthalate plasticizers. This claim was corroborated by the Ecology Center’s tests. However, the absence of phthalates does not mean the material poses no hazard to our environment and health. PVC--regardless of which additives are used--is responsible for significant toxic emissions and pollution of nearby neighborhoods during manufacture and disposal, as well as exposing workers to toxic chemicals.

The major plasticizer identified in each of the three PVC mats was dioctyl terephthalate, or DOTP. This is an alternative to phthalates that is considered safer for human health, although data gaps remain regarding its potential for interfering with hormones.

The Suga Recycled Wetsuit yoga mat consisted of crumb-like pieces of different materials adhered together. These pieces included polyurethanes and rubbers. Some of the pieces were found to contain phthalates. The specific phthalate compound(s) were not identified.

XRF analysis also found the Suga mat contained antimony at several thousand parts per million. This level of antimony is associated with the use of antimony trioxide, a flame retardant synergist, but the reason for antimony in this yoga mat is unknown.

One yoga mat, from ISHA, was labeled TPE, a generic term meaning thermoplastic elastomer that can refer to any of several different polymers. The researchers found this mat consisted of EVA copolymer, also known as PEVA. This polymer is commonly used in hot glue and in craft foam stickers and is a better choice in terms of environmental and potential health impacts.

The remaining six mats were found to be made of polyisoprene (likely indicating natural rubber), polyurethane, or a combination thereof. Some mats included a top layer made of cork or nylon.

Ecology Center researchers urge yoga mat companies to better investigate the suppliers of their mats and label their products with accurate information rather than vague terms. At the current level of disclosure, shoppers do not have insight into how these products are impacting their world and may be misled into believing they are being eco-conscious consumers.


Ecology Center is a non-profit environmental advocacy organization established in 1970 in Ann Arbor, Michigan. The Ecology Center develops innovative solutions for healthy people and a healthy planet in primary areas: Environmental Health, Energy & Climate Change, Environmental Education, and Zero Waste. This work is accomplished through educating consumers, pushing corporations to use clean energy, make safe products, and provide healthy food, providing people with innovative services that promote healthy people and a healthy planet and working with policymakers to establish laws that protect communities and the environment. For more information visit and follow @Ecology_Center