Staff Scientist, Silent Spring Institute
The history of flame retardants stretches back at least as far as 450 B.C. when, as noted by Herodotus, the Egyptians soaked wood in alum. But it wasn’t until World War II, and the subsequent flush of highly flammable petroleum-based products into the market, that the flame retardants so popular today came into widespread use. The addition of these chemicals to our couches, TVs, and computers has soared in recent decades in response to flammability standards developed in the 1970s. Of course, we all want to protect ourselves and our families from fires. But the very regulations intended to protect us have unintentionally exposed us to chemicals that may be doing more harm than good.
Mounting research suggests that flame retardants may cause neurological and reproductive harm, thyroid disruption, and cancer. What is the latest evidence from animal and human studies? Are some people disproportionately exposed? Do less toxic alternatives exist? How can the emerging research inform chemicals policy reform? We explored these questions on a teleconference hosted by the CHE-Fertility Working Group and the Women’s Health and Environment Initiative (WHEI) on April 15.
Widely used halogenated flame retardants (usually brominated or chlorinated) are persistent pollutants that can hitchhike the globe, catching a ride on air and ocean currents, and can accumulate in wildlife, pets, and people. Foam, fabric, and plastic are soaked or coated with these chemicals so they won’t burn as easily, but because the flame retardants aren’t bound to those materials, they can escape into the air and dust in our homes and offices where we can breathe or ingest them.
In 1975, California implemented Technical Bulletin 117 (TB117)—which requires furniture to be resistant to an open flame for 12 seconds. To meet this unique flammability standard, manufacturers largely relied on penta-BDE, a commercial mixture of brominated flame retardants known as PBDEs.
“Research conducted by the Silent Spring Institute has shown the repercussions of that standard,” said Dr. Ami Zota, Postdoctoral Fellow at the University of California, San Francisco. Zota and her colleagues at Silent Spring Institute found levels of penta-BDE in California house dust that were 4 to 10 times higher than other areas in the US and 200 times higher than in Europe. The researchers also found penta-BDE in the blood of California residents at levels twice as high as the national average; and levels were higher among people with lower incomes.
In case you were thinking this is just California’s problem, think again. Dr. Arlene Blum, Executive Director of the Green Science Policy Institute and Visiting Scholar at the University of California, Berkeley, explained that although TB117 applies to products sold in California, its influence has rippled across the globe because manufacturers don’t want to vary their product formulations and many of the products we buy in the US aren’t made locally (Asia, incidentally, uses the largest volume of brominated flame retardants in the world, and that usage has risen rapidly in recent years).
“Exposures aren’t uniform across the global or even the US population,” said Zota. “Children are highly exposed because of their frequent hand to mouth behavior and close proximity to the floor…and via breast milk.” Zota pointed to a new study by Melissa Rose and colleagues that found levels of PBDEs in children that approached levels found in occupationally exposed adults.
Socioeconomic status may also affect exposure. “At least three studies have shown elevated exposures among socially vulnerable groups,” said Zota, “although this environmental health disparity has received less attention.”
The first evidence from human studies of flame retardants is emerging and, unfortunately, it is pointing to some of the same health problems demonstrated in animal studies.
“There have been numerous animal studies that have found a range of health effects from exposure to PBDEs, but very little research has been done in humans,” said Dr. Kim Harley, Associate Director for Health Effects at the Center for Children’s Environmental Health Research, University of California, Berkeley.
Harley and her colleagues measured PBDEs in the blood of women who are part of the CHAMACOS study, a long-term study examining the effects of environmental exposures on the health of mothers and children in California’s Salinas Valley. Their results showed that women with higher levels of PBDEs in their blood took longer to become pregnant compared with women who had lower levels.
“This paper is the first to address the impact of PBDEs on human fertility, and the results are surprisingly strong,” said Harley.
A recent study by researchers from Columbia University measured PBDEs in the umbilical cord blood of newborns in Manhattan, and followed up with participants through age six to test their development.
“We found that children with the highest prenatal exposures to PBDEs scored lower on tests of mental and physical development,” said Dr. Julie Herbstman, Postdoctoral Research Scientist at the Columbia University Center for Children’s Environmental Health. “While additional studies are needed to confirm our results, we should identify opportunities to reduce exposure.”
But reducing exposure to flame retardants, particularly at the individual level, is proving to be a formidable challenge. It isn’t clear, said Blum, what we should do with all of our killer couches, or what we should replace them with.
The good news is that two formulations of PBDEs (penta and octa) have been banned in the US, and deca-BDE is being phased out.
The bad news, notes Zota, is that “the persistent nature of these compounds and the slow turnover of consumer products that contain them means there will be long term exposure reservoirs for these chemicals even after they are banned.” Take your sofa, for example, which has an estimated 30-year lifespan.
Furthermore, alternative flame retardants have been substituted that haven’t been adequately tested for safety, such as the widely used Firemaster 550 and chlorinated Tris—a close relative of a flame retardant (brominated Tris) banned from children’s pajamas in the 1970s because it is carcinogenic.
“The problem,” explained Blum, “is that chemicals in America are not effectively regulated.” The Toxic Substances Control Act (TSCA), our primary federal chemicals policy, is widely recognized as being limp and outdated. “In 30 years there has been no incentive for the companies that make these chemicals to develop any new green or less toxic flame retardants, and when one is banned they just move to the next one.”
This may be changing. Senator Frank Lautenberg (D-NJ) recently filed legislation that would require manufacturers to demonstrate the safety of chemicals before they are put on the market, and to submit health and safety data to the EPA for the over 80,000 chemicals that are already in use.
As for TB117 and other flammability standards, Blum questions their effectiveness. “There is no data that flame retardants have saved lives, but there is evidence they may be harming the planet and our health,” she said.
Fire retardants can delay fires for a few seconds, but they can also generate more carbon monoxide, smoke, and other pollutants, which can make fires even more dangerous. And while fire deaths have declined since the 1980s in California, there’s been a similar decline in other states, with the largest (nearly 50%) in New York. This could be due to a 50% decrease in smoking over the same time period, fire-safe cigarettes and candles, improved fire codes, and increased use of sprinklers and smoke detectors.
Blum suggested several alternative strategies for reducing fire hazards, including:
- Using flame retardant chemicals only when a fire safety benefit has been established
- Reducing ignition sources, which is more effective than adding flame retardants
- Using non-halogenated flame retardants when needed
- Using alternative technologies such as barriers
- Updating flammability standards
- Providing information to the public
There are two bills this year in California tackling different aspects of the flame retardant problem. SB772 would stop the de facto requirement for flame retardants in foam baby products where there is no demonstrated fire hazard; SB1291 would require health information before flame retardants are used and a costs and benefit analysis of standards like TB117.
The European Union, which has already restricted the use of PBDEs, is currently reforming its Directive on the Restrictions of Hazardous Substance (RoHS) in electrical and electronic equipment. Clean Production Action is advocating for a ban on all halogenated flame retardants in electronic products on the market in Europe, which, if passed, could have a worldwide impact.
Blum, who is also a mountain climber, closed the teleconference with an image of herself, ascending a precipitous snow-capped mountain peak. “I feel like I’m on an expedition with all of you who are part of this call,” she said. “It’s a small number of companies and chemicals with a huge adverse impact on the health and environment of everyone. Working together we can climb the mountain and reach a safer healthier place.”