January 19, 2010 -- Prenatal exposure to ambient levels of flame retardant compounds called polybrominated diphenyl ethers (PBDEs) is associated with adverse neurodevelopmental effects in young children, according to researchers at the Columbia Center for Children’s Environmental Health (CCCEH) at Columbia University’s Mailman School of Public Health.
The study is online in Environmental Health Perspectives and will be released in the April 2010 print issue.
PBDEs are endocrine-disrupting chemicals and widely used flame-retardant compounds that are applied to a broad array of textiles and consumer products, including mattresses, upholstery, building materials, and electronic equipment. Because the compounds are additives rather than chemically bound to consumer products, they can be released into the environment. Human exposure may occur through dietary ingestion or through inhalation of dust containing PBDEs.
The researchers found that children with higher concentrations of PBDEs in their umbilical cord blood at birth 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 5.5 to 8.0 points for those with the highest prenatal exposures.
“The neurodevelopmental effects of prenatal exposure to PBDEs have not previously been studied among children in North America, where levels are typically higher than in Europe or Asia,” said Julie Herbstman, PhD, first author on the paper and a research scientist in Environmental Health Sciences at the Mailman School of Public Health. “The findings are consistent with effects observed in animal studies and, if replicated in other North American populations, they could have important public health implications.”
Frederica Perera, DrPh, professor of Environmental Health Sciences at the Mailman School, CCCEH Director, and coauthor added, “These findings are of potential concern, because IQ is a predictor of future educational performance; and the observed reductions in IQ scores are in the range seen with low level lead exposure.” This research underscores the need for preventive policies to reduce toxic exposures occurring in utero.”
The investigators controlled for factors that have previously been linked to neurodevelopment in other studies, including ethnicity, mother’s IQ, child’s sex, gestational age at birth, maternal age, prenatal exposure to environmental tobacco smoke, maternal education, material hardship, and breast feeding.
The study is part of a broader project examining the effects of chemicals released by the World Trade Center’s destruction on pregnant women and their children. However, residential proximity to the World Trade Center site did not affect levels of PBDE exposure.
Other investigators from the Mailman School of Public Health or the Centers for Disease Control and Prevention are Andreas Sjödin, PhD, Matthew Kurzon, MS, Sally A. Lederman, PhD, Richard S. Jones, Virginia Rauh, PhD, Larry L. Needham, PhD, Deliang Tang, MD, DrPH, Megan Niedzwiecki, and Richard Y. Wang, DO.
The study was funded by the National Institutes of Environmental Health Sciences, the New York Community Trust, the New York Times Company Foundation, and the September 11 Children's Fund.
The Columbia Center for Children’s Environmental Health --part of Columbia University’s Mailman School of Public Health -- is a leading research organization dedicated to understanding and preventing environmentally related disease in children. Founded in 1998, the Center conducts research in New York City, including the study of mothers and children in Northern Manhattan and South Bronx, a World Trade Center Study, as well as cohort studies in Krakow, Poland, and Chongqing, China. Its mission is to improve the respiratory health and cognitive development of children and to reduce their cancer risk by identifying environmental toxicants and conditions related to poverty that increase their risk of disease. In NYC, the Center collaborates with residents and partner organizations in Washington Heights, Harlem and the South Bronx to share research findings with the local communities in ways that are meaningful and usable in daily life. The CCCEH is one of several National Centers funded by the NIEHS and EPA and one of three Disease Investigation through Specialized Clinically-Oriented Ventures In Environmental Research (DISCOVER) Centers funded by the NIEHS. www.ccceh.org.
The only accredited school of public health in New York City and among the first in the nation, Columbia University’s Mailman School of Public Health pursues an agenda of research, education, and service to address the critical and complex public health issues affecting millions of people locally and globally. The Mailman School is the recipient of some of the largest government and private grants in Columbia University’s history. Its more than 1000 graduate students pursue master’s and doctoral degrees, and the School’s 300 multi-disciplinary faculty members work in more than 100 countries around the world, addressing such issues as infectious and chronic diseases, health promotion and disease prevention, environmental health, maternal and child health, health over the life course, health policy, and public health preparedness. www.mailman.columbia.edu