A major state-owned industrial conglomerate in China said Friday it had been ordered to stop production at one of its smelters after it was found to be leaking highly toxic thallium into a river.
Shenzhen Zhongjin Lingnan Nonfemet Co Ltd (NONFEMET) said in a statement that environmental authorities had found excess thallium in the middle and upper reaches of the Bei River in the southern province of Guangdong.
"It was determined through expert consultations, investigations and monitoring by environmental authorities that the excessive thallium was caused by sewage from the firm's smelter in Shaoguan city," it said.
"The Shaoguan smelter completely stopped production on October 21 at the request of the provincial government, and is now actively coordinating with the government's investigations," it added.
Thallium is a highly toxic metal that enters the environment mostly through coal-burning and smelting. It can affect the nervous system, lungs, heart, liver, and kidneys, and even cause death.
China suffers from widespread water pollution after years of unbridled economic growth. According to government data, more than 200 million Chinese currently do not have access to safe drinking water.
But the Asian nation, which has pledged to slash its energy consumption per unit of gross domestic product by 20 percent between 2006 and 2010, is seeking to reduce pollution and clean up the environment.
It has implemented measures such as ordering the closure of thousands of highly polluting plants and threatening to rescind promotions for officials if they fail to meet environmental targets, but accidents still occur.
A toxic waste spill at a copper plant in July in southeastern China devastated marine life and earned its parent company Zijin Mining a 1.4-million-dollar fine.
NONFEMET, one of China's 500 largest companies, is listed on the Shenzhen Stock Exchange.
It said in its statement to the exchange that the impact on the river had now been "effectively controlled" but gave no more details on the amount of thallium that was discovered.
Calls to the Shaoguan environmental protection department went unanswered.
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