Invisible
Export – A Hidden Cost of China's Growth: Mercury Migration
Turning to Coal, Nation Sends Toxic Metal Around Globe; Buildup
in the Great Lakes Conveyor Belt of Bad Air
The
airborne output of Chinese power plants like Wuhu Shaoda was
once considered the price of China's economic growth, and a
mostly local problem. But just as China's industrial might is
integrating the country into the global economy, its pollution
is also becoming a global concern. Among the biggest worries:
the impact of China's vast and growing power industry, mostly
fueled by coal, on the buildup of mercury in the world's water
and food supply.
Matt Pottinger, Steve Stecklow, and John J. Fialka, The Wall
Street Journal, 20 December 2004
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On a recent hazy
morning in eastern China, the Wuhu Shaoda power company revved
up its production of electricity, burning a ton and a half of
coal per minute to satisfy more than half the demand of Wuhu, an
industrial city of two million people. AES Corp., an American
energy company, owns 25% of the 250-megawatt facility, which
local officials call an "economically advanced enterprise."
The Chinese plant is outfitted with devices that prevent soot
from billowing into the sky. But other pollutants, such as
nitrogen oxides, sulfur dioxide and a gaseous form of mercury,
swirl freely from the smokestacks. Rather than install more
sophisticated and costly antipollution equipment, the plant,
which is majority owned by state-controlled entities, has chosen
to pay an annual fee, which it estimates will be about $500,000
this year. That option meets Chinese standards but wouldn't be
allowed in the U.S.
The airborne output of Chinese power plants like Wuhu Shaoda was
once considered the price of China's economic growth, and a
mostly local problem. But just as China's industrial might is
integrating the country into the global economy, its pollution
is also becoming a global concern. Among the biggest worries:
the impact of China's vast and growing power industry, mostly
fueled by coal, on the buildup of mercury in the world's water
and food supply.
Scientists long assumed mercury settled into the ground or water
soon after it spewed forth as a gas from smokestacks. But using
satellites, airplanes and supercomputers, scientists are now
tracking air pollution with unprecedented precision, discovering
plumes of soot, ozone, sulfates and mercury that drift eastward
across oceans and continents.
Mercury and other pollutants from China's more than 2,000
coal-fired power plants soar high into the atmosphere and around
the globe on what has become a transcontinental conveyor belt of
bad air. North America and Europe add their own dirty loads to
the belt. But Asia, pulsating with the economic rebirth of China
and India, is the largest contributor.
"We're all breathing each other's air," says Daniel J. Jacob, a
Harvard professor of atmospheric chemistry and one of the chief
researchers in a recent multinational study of transcontinental
air pollution. He traced a plume of dirty air from Asia to a
point over New England, where samples revealed that chemicals in
it had come from China.
One reason China's power industry spews out so much pollution is
that under the nation's rules, many plants have the option of
paying the government annual fees rather than installing
antipollution equipment. Moreover, Beijing officials concede
they lack the authority to shut down heavily polluting plants.
And local inspectors, who don't report to Beijing, are reluctant
to crack down on power companies that generate jobs.
In the U.S., the consequences are being detected not just in the
air people breathe but in the food they eat. The U.S.
Environmental Protection Agency recently reported that a third
of the country's lakes and nearly a quarter of its rivers are
now so polluted with mercury that children and pregnant women
are advised to limit or avoid eating fish caught there. Warnings
about mercury, a highly toxic metal used in things ranging from
dental fillings to watch batteries, have been issued by 45
states and cover four of the five Great Lakes. Some scientists
now say 30% or more of the mercury settling into U.S. ground
soil and waterways comes from other countries – in particular,
China.
The increasingly global nature of the problem is rendering local
solutions inadequate. Officials in some countries are using the
presence of pollution from abroad "as an argument to do nothing
[at] home," says Klaus Toepfer, executive director of the United
Nations Environment Program in Nairobi, Kenya.
Yet global remedies – primarily treaties – are even harder to
achieve. The last such initiative, the Kyoto Protocol, aimed at
limiting emissions related to global warming, was rejected by
the U.S., the largest contributor of such emissions – and
doesn't apply to China, the second-largest emitter. The best
shot at a treaty for transcontinental pollution, Mr. Toepfer
believes, would be to regulate a single pollutant that everyone
agrees is hazardous. He recommends starting with mercury.
China is already believed to be the world's largest source of
nonnatural emissions of mercury. Jozef Pacyna, director of the
Center for Ecological Economics at the Norwegian Institute for
Air Research, calculates that China, largely because of its coal
combustion, spews 600 tons of mercury into the air each year,
accounting for nearly a quarter of the world's nonnatural
emissions. And the volume is rising at a time when North
American and European mercury pollution is dropping. The U.S.
emitted about 120 tons of mercury into the air in 1999 from
manmade sources. Chinese power plants currently under
construction – the majority fueled by coal – will alone have
more than twice the entire electricity-generating capacity of
the U.K.
The overwhelming majority of China's power plants are built,
owned and operated by Chinese companies. Speaking about the Wuhu
Shaoda power plant, Robin Pence, a spokeswoman for AES, says the
Arlington, Va., company "is a minority partner in Wuhu. As such,
we neither operate nor control the plant." She adds that AES
didn't build the plant and that its world-wide policy for plants
that it does design and build is to meet emission standards set
either by the local country or the World Bank, whichever are
more stringent. The Wuhu plant's manager declined to comment.
Natural Sources
EPA scientists estimate that a third of the mercury in the
atmosphere gets there naturally. Traces of the silvery liquid in
the earth's crust make their way into the sky through volcanic
eruptions and evaporation from the earth's surface. It took the
industrial age to turn mercury into a public-health concern.
Mining, waste incineration and coal combustion emit the metal in
the form of an invisible gas. After it rains down and seeps into
wetlands, rivers and lakes, microbes convert it into
methylmercury, a compound that works its way up the food chain
into fish and eventually people.
The dangers of significant methylmercury exposure to the nervous
system are well documented, particularly in fetuses and
children. Permanent harm to children can range from subtle
deficits in memory and attention span to mental retardation. In
January, EPA scientists released research indicating that
630,000 U.S. babies born during a 12-month period in 1999-2000
had potentially unsafe levels of mercury in their blood – about
twice as many babies as previously estimated.
Adults aren't immune, either. Joel Bouchard, a National Hockey
League defenseman who spent the past two seasons with the New
York Rangers, says that last December he began suffering
dizziness, headaches, insomnia and blurred vision – forcing him
to miss around 25 games. "It was, honestly, like I was in the
Twilight Zone," he says. A team doctor discovered Mr. Bouchard
had abnormally high levels of mercury in his bloodstream. The
suspected cause: the tuna and other fish he'd been eating almost
daily as part of what he thought was a healthy diet. He says his
blood levels have since returned to normal and the symptoms have
disappeared.
Few places more starkly illustrate the threat from mercury, and
the obstacles to containing it, than China.
In Qingzhen, a town in the poor mountainous province of Guizhou
about 800 miles southwest of Wuhu, a 53-year-old female rice
grower who goes by the single name of Zhang and thousands of
other farmers are surrounded by mercury pollution. Dark smoke
surges from the local power plant, staining crops a drab gray.
The plant flushes eight million cubic meters, or about 10
million cubic yards, of ash and water each year into an area
adjacent to a major drinking-water reservoir. Some fish near the
plant have levels of mercury 18 times what the EPA and the
Chinese government consider safe, according to the Guizhou
Provincial Environmental Science and Research Institute, which
recently did a seven-year study of the province's mercury
pollution.
The plots of land that Ms. Zhang and her neighbors tend are
especially poorly situated. Nearby is the Guizhou Crystal
Organic Chemical factory, which over the years released up to
100 tons of mercury into a stream that runs through her village,
according to the study. An official in the factory's environment
and safety department calls the report's estimate "too high,"
and says the factory stopped dumping mercury by 1998. But the
stream still runs black and reeks so strongly of chemicals that
people unaccustomed to the smell struggle not to gag when
standing downwind.
Ms. Zhang and her neighbors are used to the smell. With no other
choice, they pump water from the poisoned stream onto dozens of
acres of rice paddies each planting season. Rice from the fields
tastes sour, she says. "When you wash it, the water in the pot
turns the same color as the river." Grain from these fields
contains nearly 40 times as much mercury as rice from Shanghai,
according to the study. Laboratory mice fed the rice became
hyperactive and their nervous systems began deteriorating within
a month, the study says.
Farmers in the village complain of periodic fits of shaking. Ms.
Zhang suspects the pollution is the reason she and some
neighbors have stomach cancer.
Once airborne, by drifting as an invisible gas or clinging to
particles of dust, mercury begins to wander. Last April, an
instrument-laden U.S. surveillance aircraft near the
California-Oregon border hit a plume of dirty air inbound from
China. Among the pollutants: black carbon, sulfur dioxide and
mercury. "Storms didn't wash it away," marvels Veerabhadran
Ramanathan of the Scripps Institution of Oceanography in La
Jolla, Calif.
Dr. Ramanathan, who helped pioneer the field of tracking
international air pollution, says such plumes shed some of the
noxious load over the ocean. But their bulk continues to drift
across the U.S. at the leisurely speed of a blimp, polluting
lakes and rivers as it goes.
The density of Chinese pollution has amazed researchers. Hans
Friedli, a chemist at the National Center for Atmospheric
Research in Boulder, Colo., recalls flying through plumes off
the Chinese coast near Shanghai two years ago that contained
pollutants in the "highest concentration that I have ever seen
from an aircraft, except when I've flown into forest fires."
And it is going to get worse. By 2020, China will have nearly
1,000 gigawatts of total electricity-generating capacity, more
than twice the current amount, according to the State Power
Economic Research Center. The majority of new plants will burn
coal. Coal-fired plants today produce three-quarters of the
country's electricity, compared with around 50% in the U.S.
China will this year burn about 1.9 billion tons of coal, a 12%
increase from last year, and consumption is expected to keep
rising.
China is phasing in several measures to tackle air pollution.
But soot plus sulfur dioxide and nitrogen oxides – often
referred to as "SOx and NOx" – are understandably taking
priority over mercury. Even with the existence of poisoned
villages like Ms. Zhang's, other pollutants affect even more
Chinese people. Airborne particulates are a suspected leading
cause of respiratory disease around the country. Acid rain from
sulfur dioxide now pelts a third of China's territory, a ratio
that is "expanding, not shrinking," says Pan Yue, the deputy
director of China's State Environmental Protection
Administration, or SEPA.
Mr. Pan, an outspoken champion of stricter environmental
standards, says there currently aren't any rules being drafted
to address mercury. Asked if he is aware of recent studies
linking Chinese emissions to mercury in American lakes and
rivers, he nods.
"As for China's impact on surrounding countries, I'm first to
admit the problem. But let's talk about this in the context of
international fairness," he says, before firing rhetorical
questions aimed at Washington: "Whose development model are we
emulating? Who has been shifting all of its pollution-heavy
factories to China? ... And who bears an even greater
international responsibility than China – but has yet to
shoulder it – on matters like greenhouse-gas emissions?"
Environmentalists say U.S. action to control its own mercury
emissions from power plants has been sluggish. James Connaughton,
head of the White House Council on Environmental Quality,
counters that the Bush administration has promised by next March
to announce regulations aimed specifically at restricting
mercury emissions from coal plants, which he calls a "world
first." The plan, which follows years of delays and lawsuits, is
expected to include market-based trading of pollution credits
among utilities and won't be implemented fully until 2018. Other
technologies, such as flue gas desulfurisation, that remove some
mercury while scrubbing other pollutants from coal have helped
cut mercury emissions in Europe and North America.
Weak Incentive
On the face of it, China's new rules on sulfur dioxide should
help combat emissions of mercury, too. Beijing is requiring many
power plants approved after 1995 to install equipment that
reduces sulfur dioxide, and such equipment often has a bonus
effect of filtering out some mercury. China this summer also
increased the fees that power plants must pay for each ton of
sulfur dioxide they emit, hoping the change will give all
coal-fired power plants an incentive to buy such equipment.
But the reality is that sheer increases in Chinese coal
consumption, together with difficulty policing polluters, will
more than offset whatever reductions in sulfur dioxide and
mercury are achieved by the rules, experts say. For China, the
economics of coal remain irresistible.
It's cheaper, and "with current global reserves, it probably
wouldn't be a stretch to keep using coal another 200 years,"
says Fan Weitang, president of the China National Coal
Association. Sitting in his Beijing headquarters at Coal Tower,
a sleek new 22-story building, Mr. Fan is caught off guard by
questions about mercury pollution. "It is hard for me to discuss
that in depth," he says. Other pollutants like airborne
particulates, and SOx and NOx, receive more attention, and
"won't be much of a problem" in the near future, he promises.
That view isn't shared by Chinese scientists. " 'No problem'?
Big problem," says Tang Dagang, head of atmospheric research at
the Academy of Environmental Sciences, which is funded in part
by SEPA. By the end of last year, only 5% of the installed
capacity of coal-fired plants in China had technology to reduce
sulfur dioxide, according to official statistics. While new
rules will require the retrofitting of many plants with such
technology, Mr. Tang says older plants that account for half of
existing power-making capacity are exempt.
What's more, there is little economic incentive for power plants
like Wuhu Shaoda, the company partly owned by AES, to further
clean up its act.
Next year, Wuhu Shaoda will pay an estimated fee of $400,000 for
the several thousand tons it is expected to emit of sulfur
dioxide alone, according to an official with knowledge of the
plant's emissions. That's much less than the $14.5 million
engineers at the plant say it would cost to buy
sulfur-dioxide-removal equipment.
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