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UC Toxics News: Spring/Summer 2009 The Fire Retardant Dilemmaby Mika Pringle Tolson
Arlene Blum's life has alternated between mountains and molecules. As a graduate student in biophysical chemistry at UC Berkeley, she wanted to climb Denali. She was told women could only be allowed at base camp to help with the cooking, so she organized the first American all women's Himalayan expedition and climbed the summit of Annapurna in 1978. Blum asked the audience if they would believe that the challenges posed by chemistry are greater than her challenges climbing mountains. "What I'm doing right now in toxics I think is way more important and perhaps dangerous than climbing Annapurna." She said the problem in the United States is that most chemicals aren't effectively regulated. "We need chemical regulations in this country badly. Flame retardant chemicals are a good example." Blum began working with flame retardants in 1975 under the direction of her major professor Bruce Ames. She first looked at tris, a fire retardant in children's sleepwear. Her group conducted a study with a child who hadn't previously worn this sleepwear. After one night, they found metabolites of the tris in the child's urine. Blum and Ames wrote a paper that resulted in the banning of tris in 1977. But brominted tris was replaced with chlorinated tris, so they published another paper in 1978 and chlorinated tris was also banned.
California has a fire safety standard that foam in furniture cannot burn within the first 12 seconds, but there is no standard for the fabric. "Chemical fire retardants don't stop fires, they delay them for a few seconds," said Blum. She argued that this standard needs to be changed to protect our health. She said we are exposed to fire retardants such as polybrominated biphenyl ethers (PBDEs) through dust. Toddlers have been shown to have three times the level of their mothers because they crawl in the dust and put their hands in their mouths. "We don't have human health data yet on these fire retardants," said Blum, "but many children's conditions we see higher levels of now than 20 years ago are the same as the effects we're seeing in animals from these chemicals. " Blum said PDBEs persist in homes. They migrate from furniture to make thin films on walls and windows, and the problem lingers even after the furniture is removed. Where do they go? The National Oceanic and Atmospheric Administration has found PBDEs in sediments and in bivalves, and this ends up in marine mammals. "We have fireproof Harbor Seals," said Blum. Harbor Seals are highly contaminated with PBDEs and they have recurring disease and huge die-offs. More than seals, PBDEs have been found in all of the higher-level mammals. Scientists estimate that currently 80% of our exposure is from indoor air and dust and only 20% from our diet. As time goes on, dietary exposure will become the dominant route. "We need to get rid of the PBDE in our homes and figure out what to do with it," said Blum. Blum believes the problem can be solved. "We should only use fire retardant chemicals when there's a need. There are better ways of stopping fires. A good example is fire-safe cigarettes and fire-safe candles." Besides climbing Annapurna, Blum said the hardest thing she ever did was defeating legislation in 2007 on a new international standard that would have required all plastic enclosures for consumer electronics to resist external candle ignition. This would have resulted in the additional use of 1.7 billion pounds per year of fire retardants. She's currently working on supporting a bill in California, SB 772, to remove the fire retardant requirement from children's furniture and products. What Blum says really needs to be done is more human epidemiology studies and identifying the furniture that is toxic. The second step is to remove the furniture, but how do we dispose of it? "We really need research for end of life solutions." She ended on a hopeful note: "Using science and policy together, we can walk across the clouds." More information |
