Eight out of 10 couches contain flame retardant chemicals that are linked to heightened cancer risk, developmental delays in children or are lacking adequate health information, according to a study released today by researchers at UC Berkeley and Duke University.

(Chris Metcalf/Flickr)

The study also shows an increase in the number of couches bought throughout the U.S. that contain flame retardants. That number went up even though California is the only state that has a flame retardant regulation. While 75 percent of couches bought before 2005 contained a flame retardant chemical, the rate rose to 93 percent in couches bought since 2005, the study found.

“I didn’t expect to find such a high percentage of furniture bought outside of California to meet the standard,” said Arlene Blum, an author of the study and founder of the Berkeley-based Green Science Policy Institute. “It’s led to the use of more toxic chemicals.”

The study is coming out as California authorities, at the direction of Gov. Jerry Brown, are revising the state’s Technical Bulletin 117, which requires furniture foam to resist combustion when exposed to a flame for 12 seconds.

An updated bulletin is being drafted that will require couch upholstery to resist catching fire when it comes into contact with something, such as a cigarette, that is smoldering, according to Russ Heimerich, a spokesman for the Department of Consumer Affairs, which includes the state’s furniture safety bureau.

The change would mean that many couches would meet the fire-safety standard as they are currently made, without adding chemicals to foam, Heimerich said.

Heimerich said a draft regulation is expected to be released in December for public comment. The new rule may take effect next summer.

The study released today sheds light on which chemicals are used most frequently in furniture foam.

Researchers collected 102 samples of foam from couches bought from 1985 to 2010. They found that 85 percent of the samples contained a flame retardant. The chemicals tend to leech from foam and accumulate in household dust. People, particularly toddlers, can ingest them through hand-to-mouth contact.

The most common chemical in the couches was Tris phosphate, found in 42 couch samples. The chemical was added in 2011 to the state’s Proposition 65 list of chemicals known to cause cancer. The 1986 ballot initiative requires companies to warn consumers who would be exposed to the chemical a year after it’s added to the list.

The American Chemistry Council, which represents chemical makers, said the listing does not “automatically mean a consumer’s health is threatened.”

The second-most common chemical, discovered in 17 couch samples, was PentaBDE, which was banned in California in 2004 but remains in many couches, which most people keep for about 15 years. That chemical has been linked to problems with fertility in adults and lower IQ and impaired motor function in children.

The third-most prevalent chemical was Firemaster 550, a compound made by the firm Chemtura. While there are few studies of that chemical, one linked Firemaster 550 exposure to rapid weight gain and early onset of puberty in young rats.

Heather Stapleton, an associate professor of environmental chemistry at Duke University and an author of the Firemaster study and the couch study released today, said concerned consumers are unlikely to learn much about their own couch’s chemicals.

Many couches made outside California have no label saying they comply with Technical Bulletin 117. Yet 64 percent of couches with no label still contain flame retardants, the new study found. Also, few furniture makers can trace their supply chain back to a foam supplier to find out which fire-fighting product was used.

“There’s no way to find out if it does or doesn’t” contain flame retardants, Stapleton said. “You have no way of knowing what’s in there.”

Researchers say washing hands and dusting with a damp rag or mop are good ways to limit dust ingestion and reduce exposure.