标题: Mercury Casts Long Shadow over Wanshan [打印本页] 作者: 飞雪寒冰 时间: 2009-7-28 09:11 标题: Mercury Casts Long Shadow over Wanshan Seventy-six-year-old Wu Yangchun sits in front of a window in a small room in the village of Tuping. On the wall opposite hangs a yellowed photograph of her husband.
"He's better off than I am," Wu mumbles, seemingly to herself, while her eyelids, a hand and a leg tremble uncontrollably. "He died after only three months."
Like everyone else in this village compound in eastern Guizhou Province's Wanshan Special Administrative Region, Wu and her husband worked for many years at the nearby Guizhou Mercury mine and smelting plant. The husband worked at a smelter until 1997, when he contracted acute nasopharyngeal carcinoma from mercury vapor released during the smelting process. He died three months later.
Now, seven years later, Wu is following her husband. Because she worked in a mineral extraction process called ore dressing, her respiratory system was not directly exposed to mercury vapor.
This may seem fortunate, but it simply means her cruel struggle with mercury poisoning will drag out for a longer period than her husband's.作者: 飞雪寒冰 时间: 2009-7-28 09:11
Wu showed Caijing two medical certificates from Guizhou's Center for Disease Control and Prevention. Printed at the top of each, in large letters, is the expression "Occupational Chronic Mercury Poisoning."
Wu's condition has steadily worsened since 2008. Mercury toxins are corroding her lungs, and she experiences bouts of coughing, phlegm, chest pressure and pain and shortness of breath. Her quivering limbs have made it exceedingly difficult to move about; it takes several minutes to climb the 10 stairs to her door. Her gums bleed, so Wu adds water to her rice until it becomes a pulpy stew so she can force it into her stomach.
"Sometimes after eating only half a bowl of rice, my mouth is full of blood," Wu says.
Wu's family is not the only one ravaged by the local mercury industry, the oldest and once the largest in China. In her apartment building alone, she says, 15 people have died from mercury poisoning over the past three years.
The local health department estimates at least 200 of the Wanshan region's 60,000 people have varying degrees of mercury poisoning. This number does not include those who have died or may be afflicted but have yet to display outward symptoms.
Guizhou Mercury closed a few years ago. But the legacy of mercury mining persists in a variety of ways. Rice paddies are contaminated, river water is tainted, and people die of cancer. Yet despite a slew of serious health and environmental consequences, illegal mercury mining and smelting continues in the Wanshan area.作者: 飞雪寒冰 时间: 2009-7-28 09:12
Mercury Capital
Wanshan is China's traditional "Mercury Capital." As early as the Tang Dynasty, which began in the 7th century, the area was known for rich deposits of mercury and cinnabar, a mercury-containing compound. The reserves were likely the largest in Asia and second largest in the world. At the local industry's peak, Wanshan mines accounted for 70 percent of the world's mercury output.
In the early 1950s, the central government opened a major mine in Wanshan called Guizhou Mercury. Over the next 30 years, the mine produced about 30,000 tons of metallic mercury and paid some 1.5 billion yuan in taxes. At today's price levels, the company's total output would be worth about 12.4 billion yuan.
The mine started running dry in the 1980s, and Guizhou Mercury lost money. By the end of 2000, the company's losses had climbed to nearly 100 million yuan, and it was saddled with 157 million yuan in debt.
The area's long history of mercury mining finally ended in May 2002, when Guizhou Mercury entered government-enforced bankruptcy. The mine shut down, and soon the region's nearly 60,000 miners realized that behind the bright glow of the business boom was a dark shadow of high environmental and health costs.
By the time the mine closed, "Wanshan's mercury pollution and environmental damage had reached an extremely serious stage," Liu Shuiping, former director of the Wanshan Environmental Protection Bureau (EPB) told Caijing.作者: 飞雪寒冰 时间: 2009-7-28 09:12
Years of mineral exploitation had disastrous effects on the area's forests, groundwater and even its geology.
EPB's current director, Tian Hongchang, said a huge area between 100 and 150 meters deep underground was hollowed out in the mining process. Miners built five levels of tunnels, stacked one on top of the other and fanning out like a spider's web, beneath Wanshan's streets.
"The most serious area had seven layers of tunnels, and the narrowest area was only seven or eight meters thick, relying on only a few ore pillars for support," said Tian. "One could say that the city of Wanshan is built on an excavation hole on the verge of collapse."
But even more worrisome than the dangerous labyrinth of tunnels, Tian said, is the serious contamination of the area's environment. During its 45-year life-span, Guizhou Mercury discharged some 20.2 billion cubic meters of mercury gas, 42.6 billion cubic meters of industrial waste and 51.9 million tons of wastewater. Some of these emissions exceeded safety standards by thousands of times.
Few of these discharges were processed, leaving high levels of metallic mercury in the environment. Liu estimates at least 350 tons – equal to nearly 10 percent of the world's annual mercury emissions -- were released into the Wanshan environment.
A study by Guizhou Zunyi Medical College and other organizations the year Guizhou Mercury went bankrupt found airborne mercury levels of 0.0053 milligrams per cubic meter, 1.67 times the limit set by the government. Mercury levels in drinking water exceeded standards by more than 36 times.
Cheng Jinping, an associate professor at Shanghai Jiaotong University's School of Environment and Engineering, told Caijing that most of the mine's mercury emissions were in the form of inorganic mercury, for which the human body's absorption rate is relatively low. However, when mixed with water, relatively harmless inorganic mercury acidifies and becomes deadly methyl mercury.
In this way, methyl mercury accumulated in the area's rice paddies and vegetable plots, poisoning food.作者: 飞雪寒冰 时间: 2009-7-28 09:12
Human Price
In 2004, research conducted by a Guizhou agency for occupational disease prevention showed a link between alarming health problems in the area and mercury exposure. Until then, though, the government had not imposed any restrictions on the use of the area's contaminated drinking water, vegetables and rice.
As a result, mercury poisoning contributed to the deaths of 4.18 percent of area residents not directly involved in mercury production, officials said. Wanshan was found to be home to the nation's highest incidence rates for various types of lithiasis, or calcium stones that form inside organs. Local residents have also battled a variety of cancers.
Today, only a small amount of locally grown vegetables and other farm products can be found at markets in Wanshan. Residents rely on imports from other provinces for 90 percent of their agricultural needs. "Don't drink the water, don't eat the vegetables," has become a way of life.作者: 飞雪寒冰 时间: 2009-7-28 09:12
In addition, mercury-laden wastewater discharged from mining operations contaminated vast water resources. Caijing learned that 180 square kilometers of the river basin's 300 square kilometers have various levels of hazardous mercury contamination. Poison seeps into the basin from slag heaps left over from mercury smelting operations.
Even more worrisome is that rivers and streams in the contaminated area flow into the Yuan River, which is part of the Yangtze River drainage basin. Metallic mercury also travels downstream to the Yangtze trunk system and Hunan Province's Dongting Lake.
The huge Yangtze can dilute mercury to some extent. But many experts fear that, over time, mercury will accumulate in silt on the river bottom, creating new problems.作者: 飞雪寒冰 时间: 2009-7-28 09:12
Illegal Mining
It's been more than seven years since Guizhou Mercury closed. But recently, Tian said, unlicensed mercury smelting operations eager to profit from surging international prices for mercury have sprung up in the area.
Authorities are taking action. Jiang Ping, deputy director of the Guizhou Environmental Protection Office says that, through random patrols and mine inspections, local enforcement of laws governing mercury smelters has improved.
But Tian thinks more legal attention is needed. Small, hidden mercury "workshops" are now using guerilla tactics to evade law enforcers. "We can shut them down as we find them, reporting individual cases to higher authorities for prosecution," he said. "But it's difficult to cut it off at the source."
And the pollution problem extends far beyond smelters. The hard-hit Guizhou economy supports a variety of industrial activities that can cause mercury contamination, from battery making to gold processing, and from electric light and medical equipment manufacturing to the chemical industry. Chemical plants are the worst polluters.作者: 飞雪寒冰 时间: 2009-7-28 09:13
Legal Hurdles
Mercury is regulated in China through laws and standards designed to limit its poisonous impact on air, water and soil. But China is also the world's largest mercury consumer, using hundreds of tons annually.
The polyvinyl chloride (PVC) industry is the largest buyer of mercury in China, according to Zang Wenchao, pollution control division director at the central government's Ministry of Environmental Protection (MEP). Coal-based PVC production is preferred over oil-based PVC because China has vast coal reserves and little oil. But the use of coal requires mercury as a catalyst.
Moreover, mercury plays an important role in the production of thermometers, batteries and lights in China. It's also needed to make the energy-saving lamps currently on the market, Zang said.
China's largest mercury pollution source is coal-fired power generation, which is being expanded in the Guizhou region. But Guizhou coal contains higher levels of mercury than the fossil fuel deposits in Inner Mongolia and other parts of the country.作者: 飞雪寒冰 时间: 2009-7-28 09:13
Many of the coal-fired power plants now being built as part of a government strategy to develop economies in western regions of the country, including the West-East Power Transmission project, are in Guizhou Province.
Sheila Logan, an official working on projects involving mercury and other metals for the United Nations Environmental Program's chemicals department, told Caijing that mercury pollution control and management requires long-term commitment.
Even the United States, which has had only minor problems with mercury poisoning and has sophisticated environmental laws and supervision, is grappling with a pollution problem. Says Logan, "We must not take the problem lightly." says Logan.