China detained seven people in connection with a toxic metal spill in Guangxi province that contaminated a tributary of the Pearl River and threatened water for 1.5 million people, according to a local official.
All seven were executives at chemical plants, the official Xinhua News Agency reported late yesterday, citing Feng Zhennian, an official with the regional environmental protection department. Feng didn’t identify the executives, Xinhua said.
Chinese workers have dumped chemicals to contain the cadmium spill, detected Jan. 15 upstream of the city of Hechi, which killed fish and prompted panic buying of bottled water. Lead poisoning from battery makers, fluoride leaks from solar panel plants and acid spills from mines have sparked outrage in China, as three decades of growth transformed the nation into the world’s second-biggest economy and its largest polluter.
Pollutants were still flowing downstream, and were close to a major drinking water source for Liujiang, a city with 1.5 million people, Xinhua cited Feng as saying. The city’s water company has stepped up surveillance, he said.
Cadmium, used in batteries and paint pigments, may cause kidney dysfunction and cancer, according to the U.S. Department of Labor. The metal will have a lasting environmental impact on local fish and soil when it sinks to the riverbed, China National Radio reported, citing Li Li, a researcher at Chinese Research Academy of Environmental Sciences.
Pollutants were first detected in Longjiang river, a tributary upstream of the Liujiang river, on Jan. 15, with the cadmium concentration near the Lalang reservoir 80 times higher than the official limit, Xinhua said, citing Feng.
The pollutants were now near the Luodong hydropower station, and the concentration levels have dropped to 25 times higher than the official limit, Feng said, according to Xinhua.
The cadmium spill hasn’t affected the quality of the water at the Dongjiang river system where Hong Kong gets its supply, Gabriel Pang, a spokesman at the city’s Water Supplies Department, said by phone today. The contamination is at the Xijiang river system, he said.
Several instances of chemical spills have threatened Chinese cities’ drinking water in the past decade. A 2005 explosion at a unit of PetroChina Co. in northern China caused 100 tons of toxins to be spilled into the Songhua river, forcing authorities to shut off tap water for more than 3 million people in the city of Harbin. That incident led to the resignation of Xie Zhenhua as China’s top environmental protection official.