The Gorilla in the Closet 

Deca-BDE, a ubiquitous chemical that eluded the state's 2003 ban on toxic flame retardants, could be our next environmental nightmare.

Katrina Friedman of Oakland was alarmed to discover the milk she was feeding her infant was contaminated with a chemical that had been implicated in neurodevelopmental disorders in newborn animals. The revelation came two years ago, following her participation in a study that tested the breast milk of twenty Bay Area mothers for the presence of consumer-product flame-retardants. "The really scary part was that as a group we tested extremely high," Friedman recalls. "My levels were about twenty to forty times higher than [in similar studies done on mothers] in Sweden. That was disturbing."

The study, conducted by the Oakland-based Environmental Working Group, found levels of PBDEs -- polybrominated diphenyl ethers -- in several of the local women that were among the highest ever reported. In other local studies, the flame retardants have popped up in blood and household dust, and in fish, meat, and fowl from California supermarkets. Last summer, scientists found the compounds in tern eggs at Bay Area nesting sites. These chemicals are world travelers -- migrating as far as the Arctic -- and just like the dreaded DDT, they accumulate in people's bodies over a lifetime.

As concerns mounted, Oakland Assemblywoman Wilma Chan introduced a bill, which passed in 2003, calling for the ban of two members of the PBDE family -- "penta" and "octa" -- by 2008. Equipped with alternatives, their manufacturers agreed to beat that deadline and halt production by January 1 of this year. Some consumer product manufacturers already had stopped using PBDEs years earlier, once their toxic potential became apparent.

Crisis averted, right? Not so fast, scientists say. The research community is now sounding the alarm over a third type of PBDE known as deca-BDE -- or simply "deca" -- which escaped state legislation and the industry's voluntary phase-out due to the low levels detected in humans and a dearth of evidence regarding its harm. For many researchers and advocates, however, newer data about deca's behavior in the environment suggest that excluding it from regulation may have been a grave error.

As a class, the chemicals were intended to save lives, and they no doubt have. California's strict fire safety laws mandate that a wide variety of household products be fire resistant to ensure against a dropped cigarette sparking a catastrophe, or families being poisoned in their sleep by fumes from melting plastic. When a PBDE-containing item hits a critical temperature, it releases bromine molecules, which suppress the chemical reactions needed to propel oxygen-dependent fires.

This precaution, it now appears, comes with a dangerous catch. In lab rats, PBDEs behave like PCBs, a chemical relative banned in 1976 after being linked to human birth defects, neurological damage, and thyroid imbalances. The prevalence of the newer fire retardants in breast milk is a worrisome indicator that a mother can pass the chemicals to a nursing infant, and, far more critically, to an unborn fetus during crucial periods of prenatal brain development. Studies on animals also have shown that exposure early in life can alter reproductive structures, lower sperm count, delay puberty, and damage the ovaries.

Researchers believe the chemicals leach into the environment during their manufacture, use, and disposal. As the foam in sofa cushions breaks down in landfills over time, for example, the released PBDEs get carried by the wind and are deposited far and wide -- the "grasshopper effect," as environmentalists call it. The toxins ultimately work their way up the food chain to accumulate in humans and predatory animals. "If you look at PBDE levels in people, they vary quite substantially," explains Dr. Thomas McDonald, a national expert on PBDEs and toxicologist with the California EPA's Office of Environmental Health Hazard Assessment. "For some reason 5 percent of the population has quite high levels, and if you compare those people to [toxic levels] in animals, the margin of safety is pretty low."

Deca, the new pariah, accounts for 75 percent of the world PBDE market -- 125 million pounds of the stuff is produced every year as an additive to high-impact polystyrene plastics used in a wide variety of products: hair dryers, toasters, curling irons, coffeemakers, TVs, computer casings, printers, fax machines, smoke detectors, and light fixtures. It is used in very large amounts -- up to 15 percent of the plastic by weight. It also is added to backing in textiles for drapes, furniture, and rugs, and to some polyurethane foams.

An industry group representing the compound's two manufacturers -- Great Lakes Chemical Corp. and Albemarle Corp. -- asserts that deca remains a safe product. This claim was seemingly vindicated by a European Union risk assessment, which concluded last May following a ten-year study that "there were no identified risks to the environment or to health from the use of Deca-BDE."

The experts now believe otherwise. "Deca is the gorilla in the closet," says Dr. Kim Hooper, a leading PBDE researcher with the state Department of Toxic Substances Control. "The myth was that it is stable, doesn't degrade, doesn't disperse, stays in sediment or products, is not metabolized, and is not taken up by biota. 'Like a rock,' the manufacturers said."

The reality emerging from the past two years of research is that deca is nearly everything it was assumed not to be, scientists say. Because of its widespread use, an enormous reservoir of the chemical accumulates indoors, where people spend more than 80 percent of their time. It has been found at significant levels in household dust, in the film on the inside of windows, and in office air. Like penta, octa, and PCBs, it now also appears to cause neurodevelopmental damage in animals.

Unlike its banned siblings, deca seems to pass through the body rapidly, which would account for the relatively low levels detected in human tissues. But scientists believe, and recent data suggest, that the larger compound -- named for the ten bromine atoms it contains -- may be broken down by sunlight into smaller molecules, including its toxic, banned family members. Call it a Trojan horse: Scientists now believe that some of the penta and octa detected in humans and the environment is likely deca in disguise. This doesn't sit well with McDonald, who dismisses the EU's risk assessment. "The new data that deca loses its bromine in the environment and forms the lower-brominated BDEs was not dealt with appropriately by the European Union evaluation," he says.

Peter O'Toole, US director of the Bromine Science and Environment Forum, which represents the PBDE manufacturers, maintains that the breakdown of deca into penta and octa has not been concretely demonstrated, "but is certainly something that we are investigating."

Those who have reviewed the existing data need little convincing. "The final reality," Hooper says, speaking conservatively, "is that we have more than a half-billion pounds of the stuff above ground in consumer products in close human contact, and another half-billion below ground in sediment. This billion pounds eventually breaks down; into what, we don't know. Is this a good idea? Scientists don't think so. It's become less of a scientific question -- now it's more like a question of politics."

Politicians, unfortunately, have a poor track record in protecting people from inadequately studied chemical additives. In the case of fire retardants, opponents invariably dust off the classic cost-benefit question: When does the harm a product might cause supersede the lives it definitely saves?

It is perhaps too much to hope for that new chemicals be studied for human and environmental toxicity before they are rushed pell-mell into products for the kitchen or nursery. Absent any federal precautionary philosophy, chemicals in this country are innocent until proven guilty. By the time a convincing scientific case can be built against them -- and the more profitable the chemical, the more evidence needed to indict -- they are already in the midst of an often-lengthy life cycle.

"Under our old pollution mentality, we used to think of smokestacks as responsible for our exposure to hazardous chemicals," says Sonya Lunder, coauthor of Environmental Working Group studies on PBDEs in dust and breast milk. "But we're finding chemicals in everyday household products -- furniture, Teflon pans, cosmetics -- to be very dangerous."

In the meantime, new mothers must face a harrowing personal cost-benefit analysis. The expert consensus: Don't stop breastfeeding. "There is something about breastfeeding and nutrients and the different factors it provides that rescues toxic insults that may have happened during gestation," researcher McDonald says. "We're after optimal health, where mothers should breast-feed and where there are low to insignificant levels of persistent pollutants in their bodies."

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