Oakland Tribune
December 12, 2005


Evidence suggests chemical may break down in the body

By Douglas Fischer

The molecule is supposed to be stable, unreactive, hard to digest.

It may, in fact, be none of those.

It is a brominated flame retardant -- astonishingly effective at
delaying fire in plastic. In today's world, the value of such power
cannot be underestimated.

Blazes sparked by televisions, stereo equipment, VCRs and other home
electronics account for the largest number of fire deaths in the
United States.

But the flame retardant, known to the industry as "Deca," also shows
up in our bodies. And there is much debate about what happens once it
gets there.

Deca is one of three brominated flame retardants known collectively as
PBDEs and commonly found in the home.

The other two, dubbed "Penta" and "Octa" for the number of bromine
atoms, are found in foam and textiles and have been banned in Europe,
California and Maine. The only U.S. manufacturer ceased production
earlier this year.

So that leaves Deca, which traditionally accounted for almost 80
percent of global PBDE demand -- nearly 54,000 tons in 2001, according
to industry.

Manufacturers insist a vast wealth of studies make the case that Deca
is a very large, very inert molecule, with large quantities needed to
produce ill health effects in laboratory animals. Unlike other,
smaller PBDEs, where levels found in humans are approaching those
thought to cause harm in animal studies, Deca exposure falls well
below any health threshold.

But new research on workers handling Deca in Sweden suggests the
chemical might break down in the body, morphing into smaller
brominated compounds.

And an Oakland Tribune investigation of one family's chemical "body
burden" -- the amount of synthetic chemicals we pick up from our
environment -- found some of the first hints that Deca levels might
change dramatically.

"Deca is a strange molecule. It's complicated. And that complication
should be a warning sign," said Kim Hooper, research supervisor for
the California Environmental Protection's Hazardous Materials
Laboratory. "No one's tested the breakdown products of Deca. Nor have
they really identified them."

That is because industry says the science shows it does not have much
effect, even if it does break down.

"It's poorly absorbed and very high in the no-effect level (found in
animal studies)," said Ron Zumstein, vice president for health, safety
and environment at Louisiana-based Albemarle, a chief Deca
manufacturer. "So you take a study... and now go and look for
metabolites, that doesn't change the original toxicology work.

"You're still looking for effects," Zumstein said. And so far, no lab
is seeing any.

A comprehensive data summary compiled by the American Chemistry
Council for the U.S. Environmental Protection Agency concluded even
large doses over time would have no effect, largely because the
molecule is too large to stick around in fat or blood.

A typical 4-year-old, for instance, could eat two-thirds of an ounce
of Deca a day for many years and still not see any ill effects, the
summary concluded. Typical ingestion models for children suggest they
consume perhaps 200 nanograms of Deca a day -- the difference, roughly,
between eating 500 pounds of beef in one sitting and swallowing a
grain of salt.

But that may not be the full picture. In September, Stockholm
University researchers published results of a study of vacationing
Swedish workers handling Deca for a living. As these workers
vacationed, they found, the Deca in their blood dropped precipitously
-- so fast that half their body burden disappeared during a two-week

What's more, workers with the highest Deca levels also had high levels
of PBDEs rarely seen in the general public. These compounds, the
researchers said, are breakdown products created as the body attacks
and digests Deca molecules.

These products also show up in the Hammond Hollands, a Berkeley family
of four that had their blood, urine and hair analyzed for such
chemicals as part of the Tribune's investigation.

The family was picked because it tried to avoid synthetic chemicals,
yet lab tests found PCBs, plastics, mercury and lead in each family

The surprise was PBDEs. Michele Hammond and Jeremiah Holland were
within the normal range for adults in California. But their two young
children were as high -- particularly in Deca -- as the Swedish workers.

Ake Bergman, the Stockholm University professor who first alerted the
world to rapidly rising PBDE levels and helped spearhead the recent
research on Deca, examined the Tribune's results and analyzed blood
taken from the family three months after the first sample.

Bergman found Deca levels nearly one-tenth of the initial test but
still, for the two kids, near what he found in Swedish electronics
dismantlers. Levels of the smaller PBDEs, known to linger in the body
longer, did not change.

The results are controversial, but they suggest, Bergman said, the
Hammond Hollands somehow experienced a "pulse" of Deca in September
2004, when they were first tested. That pulse had largely disappeared
by December 2004, when the second sample was taken.

What that means for our health is uncertain. But it suggests levels
could fluctuate wildly and rapidly in the general population. And that
maybe, as Deca leaves the body, it also leaves other PBDEs that break
down into smaller molecules that stick around for a while.

And that has government scientists like Hooper concerned there is more
to Deca than we might know.

"Our position -- that's really the most conservative -- would be that
we'd ask the manufacturers to show that it's not breaking down or that
it is leaving the body," he said.

"Until they can do that, we just don't use it."