Polybrominated diphenyl ethers (PBDEs) are widely used flame-retardant compounds that are applied to a broad array of textiles and consumer products, including mattresses, upholstery, carpeting, building materials, and electronic equipment. Because the compounds are additive rather than chemically bound to the products, they can be released into the environment. They are persistent organic chemicals and can bioaccumulate; therefore, they have become contaminants detectable in the environment, in animals, and in humans.
Human exposure may occur through ingestion of foods or dust containing PBDEs. Inadvertent dust ingestion may be a particularly important source of PBDE exposure among toddlers, who spend a lot of time on the ground and are far more likely to put their hands in their mouths than older children and adults. In the U.S., all PBDE commercial mixtures will be phased out of production by 2013. However, it is likely that long-term exposure will continue long after PBDE production has ended through emissions from PBDE-containing products that are still being used. Dietary exposure of PBDEs will occur as they accumulate in the food chain.
What We Know About PBDES
PBDEs are considered endocrine disrupting chemicals, which are synthetic chemicals that when absorbed into the body either mimic or block hormones and interfere with the body’s normal functions. This disruption can happen through altering normal hormone levels, halting or stimulating the production of hormones, or changing the way hormones travel through the body. In animal and some human models, PBDEs have been found to disrupt thyroid hormones, which are critical for normal brain development. Brain development, mediated by thyroid hormones, begins in utero and continues throughout early childhood. Thus, PBDE exposure during this period could be especially detrimental. In addition, studies have found that children have much higher concentrations of PBDEs than do adults.
In a recent analysis and publication from our World Trade Center longitudinal cohort study, we reported that children with higher concentrations of PBDEs in their umbilical cord blood scored lower on tests of mental and physical development between the ages of one and six. Developmental effects were particularly evident at four years of age, when verbal and full IQ scores were reduced by 5.5 to 8.0 points for those with the highest prenatal exposures. One of the limitations of this study was that in this cohort, we had no way of estimating postnatal exposure to PBDEs, which may influence neurodevelopmental endpoints. We are currently in the process of attempting to replicate these findings in our flagship cohort study in Northern Manhattan, where we have the added benefit of being able to measure both pre- and postnatal PBDE exposure.
See the video below to view the Center’s Julie Herbstman speak about the hazards found in flame-retardant materials:
What You Can Do
Reduce exposure in your home
- Though many new foam products are PBDE-free, mattresses, mattress pads, recliners/easy chairs, couches, carpet padding, and foam pillows manufactured before 2005 are likely to contain them.
- In order to reduce exposure from foam sources, replace anything with a ripped cover or foam that has begun to break down.
- Beware of older products where the foam is not completely encased in a protective fabric.
- Do not reupholster foam furniture.
- Avoid foam carpet padding, which is likely to contain flame retardants. Try to avoid carpeting and draperies in your home as these can be treated with stain repellents, flame retardants and other potentially toxic chemicals.
Dust your home and wash your hands frequently
- PBDEs can attach to dust particles, which we then inhale or ingest.
- Use a wet mop and a vacuum fitted with a HEPA filter, which trap small particles more efficiently and will likely remove more contaminants and other allergens from your home.
- Wash your hands with soap and water. Hand-to-mouth contact is a major path for human exposure to flame retardants, lead, and pesticides which are found in house dust.
Read Labels Carefully
- Avoid upholstered furniture that contains polyurethane foam and has a label stating it meets the California furniture flammability standard. Technical Bulletin 117 (TB117). Such furniture is likely to contain flame retardants that are toxic or untested. They also do not increase fire safety.
- Nursing pillows, strollers, baby carriers and other baby products that contain polyurethane foam and have a TB117 label are also likely to contain flame retardants even though baby products don’t pose a fire hazard.
Reduce exposure from electronics
- PBDEs are also used in computer monitors, televisions, and other electronic products.
- Purchase electronics from companies such as Acer, Apple, Eizo Nanao, LG Electronics, Lenovo, Matsushita, Microsoft, Nokia, Phillips, Samsung, Sharp, Sony-Ericsson, and Toshiba, which, in light of current PBDE research, have pledged to produce PBDE-free electronic products.
- Do not let infants and children put hand held electronics such as cell phones and remotes in their mouths.
Buy clothes and bedding made from natural fibers
- Buying fabrics made from natural fibers such as organic cotton reduces this risk of exposure. Also opt for less flammable materials such as wool and leather.
- Ask manufacturers if their products are treated with flame retardants. Some materials such as latex and natural cotton are naturally flammable and could be treated with a fire retardant method that uses toxic chemicals.
Eat a diet low in animal fats and high in fruits, vegetables, and whole grains
- Some research has shown that PBDEs accumulate in fatty tissue.
- To possibly reduce dietary consumption of PBDEs choose lean meat and poultry cuts and low-fat dairy products
- Avoid farmed fish, such as salmon, which has been shown to have particularly high PBDE levels, and choose wild fish when possible.