Wednesday, March 28, 2007

Waterproofing the Ocean: the consequence of keeping dry

“Must keep water out” was my mantra. The old red backpack, my faithful traveling companion for over twenty years, cross country, up mountains, at sea, and across the ocean had sprung a leak. Wet through completely when a drenching rain followed my husband and I down the Madison Gulf trail. Socks, underwear, warm clothes – sopping. But rather than purchase a new frame pack, I reached for the Scotchgard™, and methodically sprayed each crack, crevice and seam, confident in that by “renewing” my old pack, I was doing the right thing.

What I didn’t know then, shames me now. What I didn’t know then, apparently the 3M Company and the Dupont Corpration had known for years. That the use of, and manufacturing process for products like Scotchgard™, my Gore-Tex Coat, and the surface on my favorite fry-pan, leave behind more than just consumer goods. What we know now, according to a review recently published by Magali Houde and others from the Unversity of Guelph in the journal Environmental Science and Technology (ES&T), is that the perfluorinated polymers, the most notorious being PFOA and PFOS, used to resist, protect, and repel, have infiltrated almost every living system on earth, from Great Lakes algae to polar bears in Svalbard, from the green-lipped mussel to Kemp’s ridley sea turtle, the bald eagle and the common loon. And, unless you consider yourself separate from life on earth, these chemicals have infiltrated you, me and your next-door neighbor.

By now, this is old news. Many of us are familiar with the stories. Parrots dropping dead, 3M voluntarily “outing” PFOS, reports of PFOA and PFOS in our blood. It is old news that these chemicals persist in the environment and are found from the North Pole to the South Pole and everywhere in-between.

But how did this happen? These chemicals have been around for over fifty years. Where was the US EPA? Where were our environmental protections? Turns out, that these chemicals slipped through, legally, at least one process that would have identified their current role as the environmental contaminants de jour. That is, the Premanufacture Notification process.

Ever since Congress passed the Toxic Substances Control Act back in 1976, the EPA has had the authority to review and regulate each new chemical based on its potential threat to us, and the environment prior its use in commerce. But there’s a catch. According to the EPA, “chemicals in commerce prior to the effective date of the Toxic Substances Control Act were placed on the inventory without going through the premanufacture notice.” And, some classes of chemicals were specifically granted exemptions. These included some of the perfluorinated chemicals involved in the production of PFOA and PFOS. The idea being, according to the agency, that “certain chemical health and safety information [would] be submitted to the Agency…when companies learn of it.”

But in 2004, the US EPA charged that Dupont had violated that bit about providing “certain health and safety” information. Apparently they forgot to report that not only was PFOA persistent, but that it might be toxic to humans and the environment. Oops.

Dupont settled for over $10 million, EPA initiated a voluntary phase-out of the chemical by 2015 (a program in which Dupont along with several other manufacturers, is a participant) and back in 2000, the 3M Company voluntarily phased their use of PFOA, PFOS and related chemicals.

Phew. Glad that’s over.

Or is it?

What about those polar bears, eagles, and loons? What about the starfish, green-lipped mussels, tuna, sea-turtles and otters? Konstantinos Prevedouros and others from Stockholm UniversityE. I. duPont de Nemours, in a study published in ES&T, estimated that over the years, thousands of tons of PFOA or PFOA precursors were released to the environment, with much of it discharged into our waters. and In one case, 61% of the chemical used was released to the environment, most going right into the water, without violating a single law. Well, excepting those companies that knew, but didn’t tell. And this is only part of the legacy bequeathed upon us not just by industry but by our own desire for eggs to slide, fabric to repel, and carpets to gleam. There is no accounting of the tons of PFOS used or released over the years.

“Water is the main vector for exposure in wildlife,” says Frank Gobas, a researcher at Simon Fraser University who studies chemicals that accumulate in wildlife. In the environment, according to Gobas, perfluorinated chemicals exist in a relatively water soluble form. “Marine mammals are likely the most exposed, due to water to fish to mammal transport, which the perfluorinated chemicals tend to favor.”

The big “so what” comes from my son. Each time I begin to write, he knows it’s bad news.

“So what do those kill?” he asks peering over my shoulder.

I explain that aside from killing the occasional parrot - though Dupont and others suggest that birds are sensitive not only to fumes from overheated Teflon but from overheated butter and oils - the effects on wildlife are unknown

And although there may be ample evidence of a chemical’s toxicity in the laboratory (one form of PFOA causes neurotoxicity, liver toxicity, immuno toxicity and developmental toxicity), and ample evidence of the chemicals presence in the tissues of wild animals, one of the more challenging problems in environmental toxicology is linking the presence of that chemical in the environment with harmful effects on wildlife.

For example, Kurunthachalam Kannan, of the New York State Department of Heath, and SUNY Albany, and others, recently reported on the relationship between PFOA and PFOS concentrations in sea otters found dead or dying along the California coast and disease status. The group found more PFOA and PFOS in sea otters determined to be diseased at the time of their death, compared with those classified as non-diseased, However, according to their study, reported in ES&T, they were unable to determine if the higher levels of perfluorinated chemicals were “a cause of the disease, a consequence,or coincidental.”

Kannan’s group also reported a decline in PFOS in the otters over time, following 3M’s phase-out. Was that a surprise? “I expect that it would take much longer for the environment to respond,” says Kannan. “Maybe what we found was circumstantial, but a few other researchers have found a similar decline in seals from the Arctic.”

James Armitage, a PhD candidate at Stockholm University, studies the fate of PFOA in the environment. He agrees that once the release of these chemicals and their precursors is halted, depending on the location, environmental concentrations may decline quite swiftly.

“Given the lifespan of most creatures in the environment,” says Armitage, “I would expect to see a response to declining environmental concentrations fairly rapidly.”

“But,” he adds referring to a modeling study soon to be published, “we observed that concentrations in the North Temperate Zone, the source area, decline almost immediately, while concentrations in the North Polar Zone continue to increase.” The declines he notes are due mainly to redistribution to other ocean areas. In other words, even if phased out, the perfluorinated chemicals aren’t likely to go away soon, they’ll just go somewhere else.

According to those in the industry, there really is no replacement for perfluorinated chemicals. It is the combination of fluoride and carbon that provides the repellent properties that make these chemicals so useful and durable. The 3M Company has already developed a new polyfluorinated chemical to replace PFOA, PFOS and PFOS-related products. Their website, asserts that the reformulated products have been tested for toxicity and bioaccumulation, and have apparently passed with flying colors. But, what the site doesn’t say is that they are persistent in the environment. And though no one expects them to accumulate in the sediments, they are expected to hang around in water.

When asked about the replacement products Enesta Jones of the EPA, says “The new chemical replacements have been subject to considerable scrutiny. The Agency is requiring robust fate and toxicity testing, and will retain regulatory authority over these chemicals until we can be assured they do not present unreasonable risk.”

I hover over my daughter’s leather boots, and ponder my desire to keep her feet dry, a can of Sno-Seal silicon (non-polyfluorinated) water-guard in my hand, and begin to spray.

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