Last modified: Tuesday, March 11, 2003
Mothers and their babies have high levels of flame retardant in their blood, IU researchers find
The blood of 12 Central Indiana mothers and their infants has relatively high levels of a contaminant commonly used in plastics and electronics to prevent fires, say researchers at the Indiana University School of Public and Environmental Affairs in Bloomington and the IU School of Medicine in Indianapolis.
An abstract of their study, in the online edition of this week's Environmental Health Perspectives, stated that polybrominated diphenyl esters (PBDEs) are present in maternal and newborn blood at levels 20 or more times greater than those found in Scandinavian mothers and their babies. A separate study of California mothers and infants, also published this week in Environmental Health Perspectives, reported similar results.
While PBDEs have been shown to cause a variety of health problems in rats, no conclusive studies showing the chemicals' effects in humans have been conducted.
"We've suspected that bloodstream concentrations of PBDEs have been going up," said Professor Ronald Hites of the IU School of Public and Environmental Affairs, who led the research. "It's troubling. We're just not sure what it means yet for people's health."
Blood samples were taken from 12 Indiana mothers 18 years or older, and from the umbilical cords of their 12 babies just after birth. PBDEs were isolated from those blood samples and compared to total fat content in the blood. Brominated Diphenyl Ester-47 (BDE-47) was the most common PBDE, followed by BDE-99. The researchers found that the amount of PBDEs in the mothers ranged from 15 to 580 nanograms of PBDE per gram of blood fat, and in the infants ranged from 14 to 460 nanograms of PBDE per gram of blood fat.
Previously published studies of Swedish and Norwegian mothers and their babies -- as well as U.S. adult blood donors (females and males) from the 1980s -- showed much lower PBDE levels in these groups. The reason for the discrepancy is not known.
"Europe may not use PBDEs any more or less than the rest of the world," Hites said. "But one thing we know is that PBDEs are not manufactured in Europe, and there are at least two manufacturers of PBDEs in the United States. Europeans' exposure levels may simply be lower for reasons we don't yet understand."
Environmental Health Perspectives is a publication of the National Institute of Environmental Health Sciences. Robert Bigsby, Anita Mazdai and Mary Pell Abernathy, of the Indiana University School of Medicine, and Nathan Dodder of Indiana University's Department of Chemistry also contributed to the study. It was funded by a grant from the U.S. Environmental Protection Agency.
To speak with Hites, contact David Bricker at 812-856-9035 or brickerd@indiana.edu. To speak with Bigsby, who directed the study's clinical research at the IU School of Medicine, contact Joe Stuteville at 317-274-8881 or jstutevi@iupui.edu.
