March 12, 2003
levels of chemicals discovered in moms, babies
IU researchers say there is little data on health risks from flame-retardant
Steve Hinnefeld, Herald-Times Staff Writer
University researchers have found relatively high levels of potentially
harmful flame-retardant chemicals in the blood of Indiana mothers
and their infants.
chemicals, called polybrominated diphenyl ethers or PBDEs, were
found at levels 20 times higher than those reported in Sweden and
is the U.S. high? We don't really know," said Ron Hites, a
professor at IU's School of Public and Environmental Affairs in
worked with faculty at the IU School of Medicine and chemistry department
on the study. Their findings were published this week in the online
edition of Environmental Health Perspectives.
companion study from California, also published this week, found
similar levels of the chemicals, which are used to prevent fires
in computers, TVs and other electronic products and in polyurethane
findings bring to mind the discovery 30 to 40 years ago of the pesticide
DDT and the industrial chemicals PCBs in the tissues of birds, fish
and humans. Environmental levels of those chemicals have dropped
significantly since their uses were restricted, Hites said. But
levels of PBDEs, which are still in use, are increasing exponentially,
said the findings are troubling, but it's not clear how troubled
people should be. Lab studies have shown PBDEs to cause health problems
in rats, but relatively little is known about their effects on humans.
don't know," he said. "Reasoning by analogy with PCBs,
there are probably some (health risks). But it took us 25 years
to figure out what the health effects of PCBs were, and there's
still controversy about it."
study involved analyzing blood samples taken from 12 Indiana mothers
and their babies' umbilical cords immediately after birth. The analysis
used sophisticated techniques called gas chromatography and mass
found PBDEs at levels ranging from 15 to 580 parts per billion in
the blood fat of the mothers and from 14 to 460 parts per billion
in the umbilical cords.
said there was nothing in the experience or lifestyles of the women
to explain the different levels, or the reasons their levels were
higher than those found in northern Europe.
said it's not obvious whether human exposure is chiefly from consumer
products or industrial wastes. He knows of three factories that
manufacture PBDEs, two in Louisiana and one in Israel.
chemicals, sometimes called brominated flame retardants, are soluble
in fat and accumulate in the fatty tissues of humans and other animals.
of the early work in detecting and measuring them has been done
in Europe, particularly Sweden and Denmark. The European Union has
considered trying to regulate their use and disposal, including
a requirement that used computers be returned to manufacturers and
the chemicals recycled. U.S. authorities have been slower to talk
of this work, I've got to tell you, is in Europe," Hites said.
first heard about the chemicals at a conference in Stockholm in
1997. A Swedish researcher had studied archived samples of human
breast milk and found increasing levels of PBDEs over a 25-year
got interested and started wondering what was going on around the
Great Lakes region," said Hites, who has done important studies
of environmental levels of PCBs, dioxins and furans for 20 years.
worked with Robert Bigsby, an IU Medical School researcher, to set
up and conduct the study.
said they plan additional studies of PBDE levels in mothers and
babies. He has U.S. Environmental Protection Agency funding to look
for the chemicals in archived fish samples from the Great Lakes.
And he plans to work with the IU Medical School on studies of the
toxicology of the chemicals.