Nitrobenzene concentration in Amur in the area of Nizhne-Leninskoye is reducing. The day before, exceeding of maximum permissible concentration was detected near the settlement. However, in the evening the concentration began to reduce steadily. "Maximum nitrobenzene concentration near the settlement Nizhne-Leninskoye on the right bank of the river (Chinese People`s Republic) constituted 0,209 mg/l, which corresponds to 1,05 of maximum permissible concentration according to Russian standards", told the Russian Emergency Ministry Far-east regional centre officials. According to the sample analysis conducted both at the Chinese and Russian river banks and corresponding calculations, the front edge of contamination zone is about 100 km from Khabarovsk. The spread of toxic slick constitutes 190 km. water sample analysis is being conducted every three hour. During the last 24 hours 46 samples in three different areas have been taken. According to the Russian Emergency Ministry, forecast, the front edge of the contamination zone is expected in Khabarovsk by December 21. The forecast is being continuously corrected in correspondence with appearing data of water sample analysis. Contamination of the Amur river by chemicals took place as a result of explosion at chemical plant in Chinese town Tsilin in mid-November. Pollution zone has reached the Amur river on December 15.