The chemical plants blamed for polluting Xinqiang River in central China's Hunan Province with arsenide have been closed down...Haoyuan Chemical Company and Taolin Lead-Zinc Ore Chemical Plant were the major polluters, said an official with the State Environmental Protection Administration (SEPA). The two companies had not passed any environmental assessments and had no pollution treatment facilities. They have been discharging waste water with arsenide content more than 1,000 times higher than the national standard directly into Xinqiang River for a long time, said the official...SEPA's deputy director promised harsh penalties for the enterprises and the top managers may face criminal punishment...A chronic intake of arsenide can cause liver and kidney damage or lung and skin cancer.