Two dams in Guangdong have been closed to contain the cadmium slick in the Beijiang, or North River, discharged by a smelting plant upstream. The Baishiyao dam at Yingde and the Feilaixia dam, halfway between Yingde and Qingyuan , have been shut to prevent the slick from spreading downstream to Foshan and Guangzhou, the China Daily reported yesterday. More than 1,000 tonnes of materials highly contaminated with cadmium spilled into the river, due to mishandling during regular maintenance at the Shaoguan county smelting plant on December 16, according to Xinhua. Workers at the plant spent only one day on regular maintenance procedures that normally required three days. Factory head Zhang Weijian has been suspended while the matter is investigated, Xinhua said. The Shaoguan smelting plant is a subsidiary of the listed Shenzhen Nonfemet Technology Company. 'Shaoguan smelting plant is actively co-operating with the government's investigation and has suspended all production since December 21 as required by the provincial government,' the parent company said in a statement. It did not mention whether compensation would be provided. The plant would lose 50 million yuan directly and 100 million yuan indirectly because of the temporary shutdown. No one at Shenzhen Nonfemet Technology could be reached for comment. Several towns in the upper reaches of the Beijiang have been left without running water for about a week after environmental authorities found that the cadmium concentration in the river was 10 times the national safety limit. Warnings of possible water suspension have been issued to cities in the lower reaches, including Qingyuan, Foshan and Guangzhou. Residents in cities such as Yingde have been lining up with buckets to collect water from fire engines. The incident came on the heels of China's biggest pollution crisis last month when 100 tonnes of cancer-causing benzene was spilled into the Songhua River in Harbin after a chemical-plant explosion. In a bid to prevent a repeat of the Harbin water crisis, Guangdong officials moved quickly to disclose information to the public. They are now fighting to control the damage by diluting the slick with chemicals and monitoring the water quality at 21 stations. Fourteen metallurgy factories in Shaoguan county have been shut to prevent further pollution. The central government has also urged several neighbouring provinces to halt supplies of cadmium to Guangdong factories. Cadmium is an extremely toxic metal commonly used in factories that process or smelt ore and is used in electroplating. Long-term exposure can cause cancer.