Flame-retardant chemical could prove as troublesome a pollutant as PCBs or DDT

[Guest guest]

http://www.enn.com/news/wire-stories/2002/02/02082002/ap_46355.asp

Flame-retardant chemical could prove as troublesome a pollutant as PCBs or

DDT

Friday, February 08, 2002

By Matt Crenson, Associated Press

NEW YORK - A chemical flame retardant commonly used in foam furniture

padding is accumulating so rapidly in the breast milk of nursing mothers

that environmentalists and some scientists are calling for a ban on it.

Little is known about the toxic nature of polybrominated diphenyl ether

(PBDE). Early studies show it poses some of the same dangers as PCBs and

DDT. Those two chemicals were banned in the United States decades ago for

their myriad detrimental effects on animal and human health.

Environmentalists advocate a ban on PBDE as well. One form of the chemical

will be banned next year in Europe, where the law requires proof of safety

before a new agent can be used in the environment. U.S. law requires proof

of harm or risk before a chemical is banned.

But the chemical industry argues that more research is needed before banning

something that protects lives. Producers of PBDE say there is no evidence

that it will ever reach harmful levels, while its benefits as a flame

retardant are well known.

Adding PBDE to foam furniture padding, television casings, and other

plastics reduces by 45 percent the risk of death and injury due to fire, the

chemical manufacturers say. " We're not talking about aesthetics. People use

brominated flame retardants because they save lives, " said ,

a spokesman for Great Lakes Chemical Corp. in West Lafayette, Ind.

Like PCBs and DDT, PBDE is a persistent organic pollutant (POP). POPs can

remain in the environment for years without breaking down. Some of these

pollutants have such an affinity for fat that they build up in the bodies of

both animals and humans from before birth until death. " It seems that PBDEs

are an important - but generally unrecognized - persistent organic pollutant

in the United States, " C. Hale, a professor at the Virginia Institute

of Marine Sciences, and five colleagues wrote in the journal Nature a few

months ago.

Persistent organic pollutants are so difficult to purge from the environment

that 25 years after being banned, trace amounts of PCBs can still be

measured in human blood. In many waters, anglers are warned not to eat the

fish they catch or to limit their consumption to one or two servings a

month. " There is an enormous need to act quickly when there is a problem

with a chemical that is not only toxic but is persistent and accumulates,

because it will continue to get worse before it gets better, " said physician

, a senior scientist at the Natural Resources Defense Council.

Industry uses several forms of PBDE to decrease the flammability of various

plastics. Only one of those types, used mostly in polyurethane foam

furniture padding, has been found in the environment and in breast milk.

According to Environmental Protection Agency records, Great Lakes Chemical

is the only U.S. manufacturer of that form of PBDE.

" At this point, all bets are open in terms of how it's getting into the

environment, " said Hale, who stops short of calling for a ban on the

pollutant, which was developed in the 1960s. He has hypothesized that

discarded furniture is a major source of PBDE in the environment. Whenever

anybody tosses out an old sofa, he explained, nature goes to work. Water and

sunlight break the foam into crumbling pieces that eventually are ground to

dust. Insects have also been observed munching away at the material. From

those humble beginnings the chemical travels all the way up the food chain

to humans.

Hale has found PBDEs virtually everywhere he has looked: In a small river,

he found fish with the highest levels of PBDE ever recorded in an animal. He

has also collected sewage sludge samples from four states, all with high

concentrations of PBDE.

Swedish scientists first documented the increase of PBDE in humans. For 30

years, Sweden has sampled the breast milk of nursing mothers to track

exposure to dioxin, PCBs, and other pollutants that accumulate in body fat.

The United States has no similar program.

In 1998, Swedish scientists reported that levels of PBDE in breast milk had

increased 40-fold since 1972. Since the Swedish discovery, the chemical has

been found in Swedish pike, Virginia catfish, and North Sea cod. Seals,

moose, and reindeer all carry PBDE in their body fat and like humans,

transmit it to their nursing young. PBDE has even been found in the blubber

of sperm whales in the Arctic Ocean, far from any possible source of the

chemical.

Even more alarming to environmentalists was the revelation in December by

the journal Environmental Science & Technology that North American mothers

have breast-milk PBDE levels at least 40 times the highest concentrations

found in Sweden.

" What we have seen in our developmental neurotoxicity studies ... is that

PBDEs can be as toxic as the PCBs, " said Per sson, a toxicologist at

Uppsala University in Sweden. sson's experiments have shown that one

large dose of PBDE delivered early in a mouse's life can cause permanent

brain damage.

Similar experiments by Per Ola Darnerud of Sweden's National Food

Administration have determined that in mice, the smallest dose of PBDE that

can cause observable health effects is about 1 million times greater than

current human exposures.

But those experiments both involve relatively large amounts of PBDE given to

animals over a short time. Nobody really knows how lower doses delivered

over decades will affect humans. " I'm hoping that within two to three years

we'll have an answer, " said Crofton, a toxicologist with EPA's

National Health and Environmental Effects Research Laboratory.

Faced with similar uncertainty in May 2000, the 3M Co. chose to remove

another POP, known as PFOS, from Scotchgard and several other products. Like

PBDE, PFOS had been found to persist in the environment, but little is known

about its toxic effects.

Users of PBDE could do the same, substituting another flame-retardant

chemical in its place. But PBDE has properties other flame retardants don't,

said. It does not discolor foam or decrease its durability as much

as other flame retardants do. And though all flame retardants evaporate into

room air in trace amounts, PBDE does so at lower levels compared to many

alternatives. For that reason, Great Lakes Chemical has chosen to continue

producing its PBDE products for the time being.

" If things turn out that the levels that are going to get into the

environment are problematic, we'll do the right thing, " said.

In Europe environmental authorities have already decided that PBDE warrants

action. Beginning next year, the PBDE variety that has shown up in breast

milk will be banned. The European Parliament may end up banning the other

types as well, because some research suggests that they can break down into

the more pervasive variety after being released into the environment.

European environmental law relies heavily on the precautionary principle,

which dictates that any time a human activity may pose a threat to the

environment, it should be banned until it can be proven safe. In the United

States, regulators must show harm or an unreasonable risk before a ban.

It likely will take a few years for scientists to figure out how much of a

threat PBDE poses to human health. Then the chemical industry and government

can decide if PBDE should remain in our sofas and car seats.

No matter what they decide, we will continue living many years with a

stubbornly durable pollutant that has an inevitable attraction to the human

body.

Copyright 2002, Associated Press