More than half of U.S. couches contain potentially toxic flame retardants that pose risks to humans as the chemicals migrate from furniture foam into house dust, says a Duke University-led study published Wednesday.
Of 102 couches tested, 41% had foam with chlorinated Tris, a probable human carcinogen removed from baby pajamas in 1977, and 17% contained the chemical pentaBDE, now globally banned, according to the peer-reviewed study in Environmental Science & Technology. Most, 85%, were treated with some kind of untested or potentially toxic flame retardant.
"The levels are enormous ... People have a pound of these toxic chemicals in their couches," says co-author Arlene Blum, a chemist at the University of California-Berkeley and founder of the Green Science Policy Institute, which studies chemicals in consumer products. She says flame retardants account for up to 11% of the foam's weight and were most common in sofas five years old or less; 94% contained them.
More manufacturers have been treating polyurethane foam with flame retardants to meet a California flammability standard, known as TB117, that requires furniture sold in the state to withstand a 12-second exposure to a small open flame without igniting. Because of the size of the California market, its standard has become a de facto national one.
The study says flame retardants are linked to hormone disruption, cancer and neurological toxicity in hundreds of animal studies and several human ones. A separate study published earlier this month in Environmental Health Perspectives found that the children of hundreds of mothers who had pentaBDE in their blood during pregnancy had lower birth weight, lower IQ scores, shorter attention spans and less fine motor coordination.
The American Chemistry Council, a group representing chemical manufacturers, said in a statement that "there is no data in this study that indicates that the levels of flame retardants found would cause any human health problems."
The group says flame retardants can be an effective way to meet fire safety standards. It cites a recent analysis by one of its technical advisers showing their use in upholstered furniture can provide valuable escape time.
Yet, tests by the Consumer Product Safety Commission and other labs suggest the chemicals won't reduce fire risks but will instead burn in a few seconds, emitting toxic gases, soot and smoke that account for most fire deaths and injuries.
"The fire just laughs at these chemicals," Vytenis Babrauskas, a fire safety engineer, said in the press release accompanying the Duke-led study. "Given their toxicity, it's really the worst of both worlds."
Why use flame retardants? An investigation earlier this year by The Chicago Tribune, citing tobacco industry documents, found that tobacco companies surreptitiously pushed for flame-retardant furniture -- rather than fire-safe cigarettes -- as the best way to reduce house fires.
Manufacturers are not required to prove chemicals are safe before using them in consumer products, but California is moving to revamp its standard to improve fire safety without the use of fire retardants. If adopted, it could take effect as early as next summer.
Blum says most bed mattresses, except crib mattresses, don't contain flame retardants but most upholstered furniture does. The only way to know for sure is to have a sofa's foam chemically tested, which is expensive.
If you're buying new furniture, Blum recommends items with polyester, down, wool or cotton fillings, which are unlikely to contain flame retardants. Otherwise, to prevent ingesting household dust, she suggests frequent hand washing as well as vacuuming with a HEPA filter or wet mopping.