Following a traffic accident on Sunday, two barrels of toxic chemicals went into a river in northwest China's Gansu?Province and they have?affected the water supply of 60,000 people, official sources said on Thursday.

A truck carrying ten barrels of chemicals overturned in the county of Jiuzhaigou on the southern border with?Sichuan Province early on Sunday morning. As a result the containers went into the Tangzhu River which joins the Baishui River and flows northward into Wenxian County of Gansu, the environmental protection bureau of Wenxian said.

The Sichuan government informed Gansu of the accident in good time and Wenxian immediately suspended water supplies from the river.

Eight barrels had been retrieved by Thursday afternoon after a joint operation by the two neighboring provinces, Wenxian government said. Searches continue for the two missing barrels.

The barrels contained TDI, a toluene-like chemical often used in the manufacture of industrial paint, can be harmful to the respiratory system, eyes and skin.

There have been no reports of casualties as a result of the accident.

The county, which has a population of 243,000, had partially resumed its water supply by Thursday noon as monitoring results on five sections of the Baishui River did not show any sign of pollution, but the lower reaches of the river are under strict observation.

Around 60,000 residents living along the river have turned to mountain springs for the past four days for water. The water supply to the rest of the area was not affected.

The State Environmental Protection Administration has sent a team of officials to the county to deal with the accident.

(Xinhua News Agency May 19, 2006)