Columbia: Researchers at the Columbia Center for Children’s Environmental Health (CCCEH) within the Mailman School of Public Health report evidence of potentially harmful flame-retardants on the hands and in the homes of 100 percent of a sample of New York City mothers and toddlers. The study also found that, on average, toddlers in New York City had higher levels of common flame-retardants on their hands compared to their mothers.
The Center’s previous research has linked early life exposure to a common class of flame-retardants called PBDEs with attention problems and lower scores on tests of mental and physical development in children. The latest results appear in the journal Emerging Contaminants.
in the 1970s, manufacturers added PBDEs—persistent brominated
flame-retardants—to couches, textiles, electronics and other consumer
products to comply with flammability standards. In 2004, they began
phasing out PBDEs and started using newer alternative flame-retardants,
including TBB and TBPH, which are brominated flame-retardants and
components of the commercial mixture Firemaster 550®. Little is known
about the health effects of TBB and TBPH in humans, though they have
been linked to reduced fertility and endocrine disruption in animal models.
visited the homes of 25 mother-child pairs enrolled in the CCCEH
Sibling-Hermanos birth cohort, which began in 2008. When children were 3
years old, dust was collected from their homes and hand wipes were
collected from mother and child; these samples were then analyzed for
Signaling the widespread persistence of
the phased-out PBDEs and the prevalence of their potentially toxic
substitutes, investigators found that both PBDEs and the newer
brominated flame-retardants, TBB and TBPH, were in 100 percent of house
dust samples. On average, levels of TBB and TBPH in house dust were
higher than PBDEs. Likewise, PBDEs and TBB were found in 100 percent of
hand-wipe samples, and TBB was found in 95 percent of the samples.
Paired mother and child hand-wipe concentrations were correlated;
however, children typically had higher levels of all flame-retardants on
their hands than their mothers.
The study is the first comparison
of PBDEs, TBB, and TBPH in house dust and handwipe samples from
maternal-child pairs. Results are consistent with other studies which
have demonstrated that toddlers tend to have higher exposure to
flame-retardants when compared with adults, likely because of the amount
of time they spend on the floor.
“The extent to which young
children are exposed to these chemicals is cause for concern given the
known neurodevelopmental risk of PBDEs and the potential toxicity of
their substitutes,” says Whitney Cowell, the study’s first author and a
PhD candidate in the Department of Environmental Health Sciences at Columbia’s Mailman School.
“Toddlers are being exposed to replacement flame-retardant chemicals that we know little about,” says senior author Julie Herbstman,
associate professor of Environmental Health Sciences. “Future research
needs not only to focus on understanding the toxicity of these
compounds, but also on how exposure occurs in the home and what
behaviors and policies can be used to reduce personal exposure.”
co-authors include Heather Stapleton of the Nicholas School of the
Environment at Duke University; Matthew Perzanowski of the Mailman
School; and Darrell Holmes, Lehyla Calero, and Catherine Tobon of the
Columbia Center for Children’s Environmental Health. The research was
supported by the National Institutes of Health (grants ES021806,
ES017051, and ES09089) and by the Passport, Forsythia, and Fine
Foundations. During preparation of this manuscript, Whitney Cowell was
supported by the National Institute of Environmental Health Sciences
(grants ES023772, ES007322) and the Environmental Protection Agency