“Poison Ice” and Global Warming

——– Original Message ——–
Subject: Salon: “Poison ice” and global warming
Date: Wed, 30 Apr 2008 13:17:57 -0700
From: Fred Heutte <phred@SUNLIGHTDATA.COM>
Reply-To: Fred Heutte <phred@SUNLIGHTDATA.COM>

My friend Elizabeth Grossman, a very talented and wide-ranging
writer (her books include “High Tech Trash,” about e-waste;
“The Undamming of America” and a Sierra Club Travel Guide,
“Adventuring Along the Lewis & Clark Trail”) has now turned her
attention to the Arctic and has a good piece below published
by Salon today . . .

This is the result of research she’s doing for a book on
bioaccumulative chemicals generally but the Arctic plays a big
role in it.



Poison ice

By Elizabeth Grossman

April 30, 2008 | ARCTIC OCEAN — Over 300 miles north of the Arctic
Circle, in the polar dark of a December morning, University of
Manitoba Ph.D. student Jesse Carrie is out on the frozen Beaufort
Sea, collecting ice samples to measure for mercury and pesticides.
Lowered by crane from the deck of the icebreaking research vessel
the CCGS Amundsen, and accompanied by a rifle bearer who keeps
watch for polar bears, Carrie extracts ice cores and vials of
frigid water. Carrie is part of a $40 million International Polar
Year scientific expedition, the first ever to spend the winter
moving through sea ice north of the Arctic Circle. The expedition’s
labor-intensive work is essential to understanding the impacts of
global warming.

As the Amundsen cuts through ice across the top of the globe,
Carrie and his fellow researchers are uncovering evidence of a
disturbing fallout of climate change. They are finding toxic
contaminants, some at remarkably high levels, accumulating in this
remote and visually pristine environment. Although there are no
industrial sources in the Arctic, residents of the Far North have
some of the world’s highest levels of mercury exposure, some well
above what the World Health Organization considers safe. High
levels of mercury — a powerful neurotoxin — are being found in
Arctic marine wildlife, including ringed seals and beluga whales,
both staples of the traditional Northern diet. Levels in Arctic
beluga have increased markedly in recent years.

When coal is burned in power plants in the U.S., China and
elsewhere, mercury is released into the atmosphere. Airborne,
mercury can travel great distances before settling to the ground,
or into lakes, rivers and oceans. Air and ocean currents, propelled
by weather patterns and storm systems, sweep the mercury north. But
the recent increases in Arctic mercury outpace and cannot be
explained by smokestack emissions alone, says Gary A. Stern, a
senior scientist with Canada’s Department of Fisheries and Oceans,
professor at the University of Manitoba and co-leader of the
Amundsen expedition. Rather, signs point to global warming and
other disruptive impacts of climate change.

As temperatures rise, causing sea ice, permafrost and snow to melt,
the mercury that had been frozen in place is now being released,
causing exposure up and down the food web. “Climate change alters
exposure in the north and increases the system’s vulnerability,”
says Robie Macdonald, a research scientist with Canada’s Department
of Fisheries and Oceans.

Yet the Arctic researchers are routinely recording a lot more than
mercury. They are seeing synthetic chemicals such as the brominated
flame retardants known as PBDE’s (used in upholstery, textiles and
plastics), as well as perfluorinated and chlorine compounds. And
while long banned in many countries, lingering amounts of DDT and
PCBs continue to turn up in people and animals in the Far North. Of
concern due to their persistence and ability to accumulate in plant
and animal tissue — particularly the fat prevalent in Arctic
animals — these chemicals are also known to disrupt the endocrine
hormones that regulate reproduction and metabolism. Some are
considered carcinogens.

Alaskan polar bears, for instance, have some of the highest levels
yet found in Arctic mammals of hexachlorohexane (HCH), a pesticide
used to kill fungi on food crops. Carrie’s ice samples, collected
hundreds of miles from any agricultural sites, contain HCH. Polar
bears also have some of the highest recorded levels of
perfluorinated compounds, chemicals used in waterproofing and in
fire and stain retardants. Indigenous people in both the Canadian
and Greenland Arctic have some of the world’s highest exposures to
these persistent pollutants.

In the summer of 2007, Arctic sea ice reached a record low.
Scientists monitoring the 2008 winter ice pack suspect this year’s
summer ice may also be remarkably low. As David Barber, Canada
Research Chair in Arctic system science at the University of
Manitoba, puts it, “Well over a million years of all ecosystems
evolved to take advantage of this ice cover.” With markedly less
substantial sea ice cover, the hemispheric system is being thrown
off balance, prompting changes that are increasing the load of
contaminants in the Arctic.

As Stern explains, increased snowmelt, runoff and erosion in the
Mackenzie River Basin are also now washing naturally occurring
mercury into the Beaufort Sea. At the same time, disappearing sea
ice leaves more water exposed to sunlight, increasing the growth of
marine microorganisms and tiny plants like algae. This accelerates
the process that turns mercury into its highly toxic form called
methylmercury, which accumulates in marine mammals and fish
traditionally eaten by residents of the Arctic. “These changes are
happening much faster than anticipated,” Stern says one morning on
the Amundsen.

Decreasing sea ice is changing other dynamics of the Arctic
ecosystem. Seasonal climate changes are pushing some animals
farther to find food and prompting some to alter what and when they
eat. “With climate shift changing availability of ocean nutrients,
some birds that used to fly 50 miles to eat now have to fly 100,”
says Macdonald. “This means storing more fat, magnifying — or
concentrating — the contents of the fat, resulting in stress to
both birds and their chicks.” Because fat cells serve as a
reservoir for many contaminants, when broken down to release
energy, the toxics are also released, exposing animals from within.

In addition, says Macdonald, “Migrating fish bring with them the
contaminants they’ve hoovered up in the ocean. When the fish spawn,
they release the contaminants.” Similarly, fish-eating birds can
take up these pollutants that they then excrete. It’s possible, he
says, that animals themselves might be adding to the transport of

“The food web is quite important in terms of where contaminants are
found,” says Derek Muir, a senior scientist in aquatic ecosystems
research with Environment Canada. Warmer temperatures and shorter
ice seasons — in lakes as well as the Arctic Ocean — could alter
what happens at the bottom of the food web in ways that affect how
contaminants move up the food ladder, he explains. “Warming,” says
Muir, “could deliver more contaminants up the food chain to top
predators, and result in high levels of contaminants in very remote

Because top predators are important traditional food for Arctic
people, humans are at the top of the food web. “There is absolutely
no doubt of exposure of pollutants with harmful effects to some
groups,” says Eric Dewailly, professor of social and preventive
medicine at Laval University, who works with the International
Network for Circumpolar Health Research. There are local sources
for some metals and pollutants, but most of the persistent organic
pollutants in the Arctic come “100 percent from the outside,” he
says. Dewailly notes that because people are exposed to mixtures of
contaminants, it’s hard to isolate the precise impact of a single
one. However, studies are now being conducted in Canadian Arctic
communities to investigate links between contaminants and
cardiovascular, neurological, reproductive and immune system

Climate change is having another hazardous effect on indigenous
people. Warming temperatures have caused changes in ice conditions
and migration patterns that determine where people hunt and fish.
In some northern communities, these changes have begun to push
people toward greater dependence on supermarket food, which in
remote Arctic villages can be extremely limited.

Research by Grace Egeland, Canada Research Chair in nutrition and
health at McGill University, shows that traditional Arctic foods
tend to provide more protein, vitamins and minerals than typically
available local market food, which is usually higher in
carbohydrates, fat and sugar. “These people are feeling so many
pressures of transition that they’re now at risk,” says Egeland of
the Arctic’s indigenous communities. “There’s a human right to food
without elevated contaminants,” says Egeland. “Based on what we
know now, why wait to count the adverse events. Why wait until it’s
too late?”

But what kind of action should be taken? Can the brakes be put on
the cascading impacts of climate change? “If we could slow it down
we would,” says Barber of the shrinking sea ice. “But we can’t do
that now; there’s too much inertia in the system.”

Can we reduce the impact of the pollutants? “We can control
persistent organic pollutants,” says Muir. It’s well documented
that when hazardous chemicals — including mercury — are taken out
of use, environmental levels decrease. And if affected populations
are sufficiently healthy, they will recover.

Yet the key to controlling these pollutants, says Muir, is knowing
which are persistent, toxic, likely to climb the food web and
travel long distances. Muir explains that of the 30,000 or so
chemicals now in wide commercial use, only about 4 percent are
routinely monitored. Environmental and health impacts of about 75
percent of them have not been studied at all. Meanwhile, these
invisible substances are moving to and through the Arctic. And what
happens in the Far North, says Stern, may well presage what’s to
come farther south. “It’s the canary in the coal mine,” he says.


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