HARBIN, China -- The government defended its handling of a chemical plant explosion that sent a 50-mile-long toxic slick of river water coursing through a major city yesterday, and attributed the disaster to a subsidiary of a state-owned oil company.
The benzene slick on the Songhua River in northeastern China flowed into Harbin days after the city of 3.8 million people shut down its water system, setting off panicked buying that cleared supermarket shelves of bottled water, milk, and soft drinks. The government said the chemical would pass the city in about 40 hours.
A government official said local leaders had been warned of the chemical threat after the Nov. 13 blast that killed five people, and no one was sickened.
''It was handled properly," Zhang Lijun, deputy director of the State Environmental Protection Administration, said at a crowded news conference in Beijing.
''Authorities acted that day, and not one person has been sickened," Zhang said.
The government did not publicly confirm that the Songhua had been poisoned with benzene until Wednesday, 10 days after the explosion. But Zhang said local officials and companies stopped using river water immediately after they had been told.
The disaster has highlighted the environmental damage caused by China's sizzling economic growth and the complaints that the secretive communist government is failing to enforce public safety standards. The government said all major rivers are dangerously polluted and many cities lack adequate drinking water.
With its huge population, China ranks among countries with the smallest water supplies per person. Hundreds of cities regularly have shortages, and protests over water pollution have erupted in rural areas.
Downstream from Harbin, authorities in the Russian border city of Khabarovsk protested they had not received enough information on the threat. The Songhua flows into the Heilong River, which flows into Russia, where it is called the Amur River.
But Zhang said Beijing has shared information and might set up a hot line with Moscow.
He suggested that protests were premature, saying that the chemical would take two weeks to reach Russia.
Liu Jianchao, Chinese Foreign Ministry spokesman, said officials have briefed the Russian Embassy twice this week.
''The Chinese side attaches great importance to the potential impact and harm caused by the pollution on our neighbor Russia," he said.
The chemical plant, located in Jilin, a city about 120 miles southeast of Harbin, is operated by a subsidiary of China's biggest oil company, state-owned China National Petroleum Corp. Benzene is used in the manufacture of plastics, detergents, and pesticides.
''We will be very clear about who's responsible. It is the chemical plant of the CNPC," Zhang said. Asked if the company might face charges or fines, he said that had not been decided.
Environmentalists criticized the government for not informing the public sooner.
''Careful environmental evaluation should have been made to avoid building dangerous factories near residential areas and water sources in the first place," said Xue Ye, general secretary of the Chinese group Friends of Nature. ''The local government should have predicted the possible pollution, but they didn't."