Potentially Toxic Flame Retardants Found in Many US Couches.
More than half of all couches tested in a study by a research team that included BUSPH Environmental Health Professor Tom Webster contained potentially toxic or untested chemical flame retardants that may pose risks to human health.
Among the chemicals detected in the Duke University-led study, released Wednesday in the journal Environmental Science & Technology, was “Tris,” a chlorinated flame retardant that is considered a probable human carcinogen based on animal studies. Tris was phased out from use in baby pajamas back in 1977 because of its health risks, but it still showed up in 41 percent of the couch foam samples tested, said Heather Stapleton, associate professor of environmental chemistry at Duke’s Nicholas School of the Environment.
Tom Webster“It amazes me that the types of flame retardants used in Americans’ couches are not openly available to either consumers or environmental heath scientists,” said Webster. “That’s why we had to do this study: to figure out what’s actually there.
“We are seeing a treadmill of flame retardants in products — as one is shown to be toxic, it is replaced by another about which we know little, and the cycle repeats,” he added. “We need to change the way we regulate chemicals so they are thoroughly tested before being put in consumer products.”
More manufacturers in recent years are treating their couches’ foam padding with chemical flame retardants to adhere to California Technical Bulletin 117 (TB 177). The regulation requires all residential furniture sold in California to withstand a 12-second exposure to a small open flame without igniting, to help reduce deaths and injuries from accidental home fires. Over the years, the statewide standard essentially has become a de facto national standard, due to the economic importance of the California market.
In many cases, manufacturers may not know what chemicals have been used. Most manufacturers buy their foam padding from a vendor who, in turn, buys the chemicals used to treat it from another vendor. The identity of the chemical flame retardants often gets lost along the way, or is protected under law as proprietary, the study authors said.
The research team analyzed 102 polyurethane foam samples from couches purchased for home use in the U.S. between 1985 and 2010.
In addition to finding Tris, the tests revealed that 17 percent of the foam samples contained the flame-retardant pentaBDE, which is banned in 172 countries and 12 U.S. states and was voluntarily phased out by U.S manufacturers in 2005.
PentaBDEs are long-lasting chemicals that migrate over time into the environment and accumulate in living organisms. Studies show they can disrupt endocrine activity and affect thyroid regulation and brain development. Early exposure to them has been linked to low birth weight, lowered IQ and impaired motor and behavioral development in children.
PentaBDE and Tris were the only flame retardants found in couches purchased before 2005. After 2005, Tris was the most common flame retardant found. In addition, the research team identified two new flame-retardant chemical mixtures in more recently purchased couches for which there is little or no health data available.
“Overall, we detected flame-retardant chemicals in 85 percent of the couches we tested and in 94 percent of those purchased after 2005,” Stapleton said. “More than half of all samples, regardless of the age of the couch, contained flame retardants that are potentially toxic or have undergone little or no independent testing for human health risks.”
Chlorinated Tris, though removed from children’s pajamas due to links to genetic impacts, is being “promoted and used by the flame retardant industry to replace other banned toxic chemical flame retardants,” said co-author Arlene Blum, executive director with the Green Science Policy Institute.
Last summer, a Senate committee approved the Safe Chemicals Act, a bill that would restrict the use of hazardous chemicals, particularly those that are persistent, toxic and build up in the environment over time.
Funding for the study came from the National Institute of Environmental Health Sciences and a private donation to the Nicholas School from Fred and Alice Stanback.
Submitted by: Lisa Chedekel
chedekel@bu.edu