The Songhua River in northeast China has avoided another chemical pollution problem after ten tons of chemicals were tipped into a tributary, said a state environment official on Friday.

Zhou Shengxian, director of the State Environmental Protection Administration (SEPA), ruled out the possibility of the river pollution at a government conference.

Environmental experts had managed to contain and treat a toxic chemical slick on the Mangniu River, a tributary of Songhua, avoiding pollution damage to the waterway, the official said.

"Monitoring of the waterway in the Jilin Province section showed the water quality met national standards," said Zhou.

"No people or animals were reported to be affected by the spill in the Mangniu River," he added.

Ten tons of a toxic chemical were dumped into the Mangniu on Monday by two truck drivers in Jilin City, northeast China's Jilin Province, leaving a five-kilometer bubbling red slick.

The trucks were supposed to discharge the waste somewhere out of town.

Experts and officials from the provincial and central governments and environmental protection departments set up an emergency pollution control base at the site as soon as the incident was detected.

More than 1,000 army personnel and firefighters had built a pollution interception dam and two dams with activated carbon to absorb the pollutants. The affected water was filtered before entering the Songhua.

Tests of the polluted water identified the chemical as xylidine, which can cause damage to the liver, lungs and kidneys.

A SEPA team headed by the director has required local governments to publish information and the incident had caused no social disruption, he said.

The government of Harbin, capital of Heilongjiang Province, has informed the public on the incident and strengthened the water quality monitoring. "The supply of drinking water in the city is sufficient," said Zhou.

The drivers and five managers of the Changbaishan Jingxi Chemical Co. Company were detained for further investigation and the company ordered to cease production by the government of Jilin City, the official said.

The SEPA had informed the Russian Embassy of the incident, Zhou said.

Around 100 tons of pollutants containing hazardous benzene spilled into the Songhua River after a chemical plant explosion on last November in Jilin. The incident forced cities along the river, including Harbin, to temporarily suspend water supplies to 3.8 million people.

The Songhua flows into a major border river between China and Russia, called the Heilong River in China and the Amur River in Russia.

Former SEPA director Xie Zhenhua was sacked by the central government in December for negligence during the incident and underestimating its possible risks.

(Xinhua News Agency August 26, 2006)