California unwittingly prescribed a harmful chemical cocktail for the country in the 1970s, when it adopted rules meant to suppress fires from lit cigarettes. The regulations required foam used in upholstery to withstand a 12-second exposure to a small, open flame, triggering the widespread use of flame retardants. The effects reached well beyond the state, as manufacturers opted to adhere to a single safety standard rather than producing one set of products for California and another for the rest of the U.S.

The California rules, it turned out, were based on distorted science. Research has found that flame retardants are less effective than previously thought and pose potentially serious health risks. One class of chemicals, polybrominated diphenyl ethers, has been linked to cancer, reproductive problems and lower IQ in children. In January new rules took effect in California that free furniture manufacturers to cut back on the amount of flame retardants in their chairs and sofas. The new standards require that upholstered furniture resist exposure to a lit cigarette rather than an open flame. The change does not bar manufacturers from using flame retardants, but it makes it feasible to avoid their use.

How the industry responds remains to be seen. Even if manufacturers phased them out entirely, the chemicals would linger in the environment. Studies have shown that flame retardants in furniture leach into homes and then accumulate in the body. The chemicals also wind up in waterways and aquatic organisms.

And then there is the fact that furniture can last for generations, says Linda Birnbaum, director of the National Institute of Environmental Health Sciences. “I'm thinking of my 25-year-old couch,” she says, “and I still love it.”