Sofas and other cushy furniture often contain chemicals intended to reduce the risk of fire. But those chemicals may pose health risks of their own, and some researchers are trying to build the case for getting them out of the house altogether.
Eighty-five percent of couches tested in a new study contained at least one flame-retardant chemical in the foam cushioning.
Sofas bought before 2005 were most likely to contain chemicals called penta-BDEs, which were phased out in 2004 because of concerns that they were toxic. Manufacturers have since switched to new fire retardants, including one called called tris, or TDCPP, for short, which was found in half the 102 sofas tested.
A second study found fire retardants in household dust. In 75 percent of the homes tested, the dust contained tris, which was banned in children's sleepwear in the 1970s because it caused cancer in lab animals. Many homes also had related chemicals TCEP and TDCIPP which the state of California lists as carcinogens.
Both studies were published in the journal Environmental Science and Technology.
Why is this stuff in furniture? California has a decades-old standard requiring upholstered furniture to resist exposure to a small open flame. Most manufacturers meet that standard by using foam treated with flame retardants. And most manufacturers find it easier to use the same foam in all their furniture, rather than use retardants just in sofas that are bound for California.
But California has started having second thoughts. In 2011, it added tris to its list of carcinogens. And faced with evidence that putting fire retardants in foam does little to reduce the risk of fire, the state has started revising its furniture flammability standard.
But that doesn't do much to address the concerns of people who already have a sofa a sofa that is probably stuffed with retardants. Is this stuff really dangerous?
Federal regulators say they've been stymied in their efforts to figure out if flame retardants in sofas pose a health risk. In a Senate hearing last July, an administrator at the Environmental Protection Agency said the EPA had been unable to determine whether the chemicals could cause cancer, developmental delays in children or other problems because manufacturers aren't required to prove chemicals are safe before they're brought to market.
And the chemicals do not appear to help fight fires, Consumer Product Safety Commission chairwoman Inez Tenenbaum said at the hearing. But the agency has yet to approve a rule, proposed in 2008, that would require manufacturers to use fire-resistant cover fabrics or a barrier layer between the cover and stuffing, rather than treated foam. This is the system used for mattresses.
"There are literally thousands of peer-reviewed scientific studies on the harm of the chemicals," says Arlene Blum, a chemist and visiting scholar at the University of California, Berkeley, and a co-author on the sofa foam study. She worked on efforts to ban tris in children's sleepwear in the 1970s and now sees herself fighting the same battle over retardants in furniture.
Blum says that people can reduce their exposure without having to throw out the couch by reducing contact with house dust that's where the chemicals accumulate. Regular vacuuming with a HEPA-filter vacuum or wet-mopping should help. Hand-washing is also important, she says, particularly for small children who spend a lot of time on the floor. (Her organization, Green Science Policy Institute, gives more detailed advice.)