Crater Lake, Mount Rainier and Olympic
national parks are among wilderness areas in the Western
U.S. in which scientists have found evidence of airborne
contamination, including mercury, agricultural pesticides
and banned substances such as DDT.
A
sweeping, six-year federal study by the Environmental
Protection Agency and Oregon State University was released
Tuesday. The study found evidence of 70 contaminants in 20
national parks and monuments.
The
findings revealed that some of the earth's most pristine
wilderness is still within reach of the toxic byproducts of
the industrial age.
"Contaminants
are everywhere. You can't get more remote than these
northern parts of Alaska and the high Rockies," said Michael
Kent, an OSU fish researcher who co-authored the study
results.
The substances ranged from
mercury produced by power plants and industrial chemicals
such as PCBs to the banned insecticides dieldrin and DDT.
Those can cause health problems in humans including nervous
system damage, dampened immune system responses and lowered
reproductive success.
Other than
Crater Lake, Mount Rainier and Olympic parks, scientist
focused on primarily on these six: Sequoia and Kings Canyon
in California, Glacier in Montana, Rocky Mountain in
Colorado, plus Gates of the Arctic, Denali national parks
and Noatak National Preserve in Alaska.
The parks were most affected by contaminants
from nearby or regional sources, scientists said. For
example, concentrations of pesticides were highest in parks
closest to agricultural areas.
The
study released this week was not the first scientific report
to emerge from the Western Airborne Contamination Project,
which was completed last year.
In
May 2006, chemists announced that winter snow falling on
Mount Rainier and other high-elevation parks in the Western
states is contaminated with minute amounts of agricultural
pesticides.
Researchers uncovered a
correlation between regional farm practices and contaminated
snow at Mount Rainier and three national parks in California
and Montana.
When scientists
initiated the study, they believed airborne contaminants
tainting Western national parks came from Europe and Asia
and traveled across the Pacific Ocean before settling in the
parks. But by tracking the pollutants to their sources, they
found that results contradicted their hypotheses and that
regional sources contribute more to park pollution than
so-called trans-Pacific pollution does.
At Mount Rainier, scientists found higher
concentrations of pollutants and mercury in vegetation than
in other parks. Scientists also discovered high levels of
flame retardants in one of two lakes sampled there. The
concentrations of mercury found in both lakes were higher
than scientists believe is healthy for birds, such as
kingfishers. Also, mercury levels found in some fish were
too high for people to safely eat them.
EPA senior researcher Dixon Landers says
Yosemite National Park and Crater Lake National Park both
tested very high.
Landers says
researchers found chemicals in the plants and air around
Crater Lake.
"We are seeing
concentrations here that are elevated above the average, you
might say, of the parks we've looked at. I certainly do hope
this information will influence decision-makers," Landers
said.
Landers says current research
shows a correlation between pesticides used on a nearby
farms and pesticides found in National Park air and water.
The study also found contaminated fish in
national park lakes, though they didn't test the water in
Crater Lake.
University of
Washington atmospheric researcher Daniel Jaffe said
scientists previously thought banning substances like DDT
and dieldrin would lessen the persistence of chemicals in
the environment.
"We replaced them
with pesticides with much shorter lifetimes in the
environment," Jaffe said. "But in places like the Central
Valley of California, we are applying many, many tons of
these every year... We now know they can move substantial
distances."
A parks advocacy group
called the federal report "a wake-up call" that should
mobilize Congress to take a tougher stance on air pollution.
"We can take steps to reduce mercury
emissions from power plants, steps to reduce carbon dioxide
emissions that cause global warming," said Will Hammerquist
with the National Parks Conservation Association.
The $6 million study is the most
comprehensive to date on the distribution and concentration
of contaminants outside developed areas, according to
Landers.
Release of the study, which
was coordinated by the National Park Service, came after a
delay of several months. Park Service spokeswoman Colleen
Flanagan said the delay was caused by the time needed to
analyze the vast volumes of data collected between 2002 and
2007.
The study also included
researchers from the U.S. Geological Survey and the U.S.
Forest Service.
