Toxic benzene from northeast China's Songhua River is still passing the section 54 kilometers upstream of Jiamusi city, according to an environmental bulletin issued yesterday.
Russia has asked China to build a temporary dam, but the situation was not clear.
This section of the river is 298 kilometers away from the downstream city of Tongjiang, or the juncture of the Songhua River and the Heilongjiang River that will flow into Russia, where it is known as the Amur River.
The density of nitrobenzene at the section reached the highest level of 0.2610 milligrams per liter at noontime Thursday, exceeding the national standard 14.35 times. It began to drop after that and hit 0.2107 mg/l at midnight Thursday, still exceeding the national standard by 11.39, said the bulletin of the State Environmental Protection Administration.
At the downstream section of Jiamusi, which is 244 kilometers away from Tongjiang, the density of nitrobenzene is rising gradually. It hit 0.0780 mg/l at 4am yesterday.
At a further downstream section called Huachuan, 41.2 kilometers away from Jiamusi and 202.8 kilometers away from Tongjiang, no nitrobenzene or benzene were found yet as of 8pm Thursday.
Latest observation results show the pollutants have passed the Dalianhe section of Yilan County, 388 kilometers away from Tongjiang.
(Xinhua)