"reuters Pollution levels from a red sludge spill in Hungary have subsided in the Danube and there is no risk of a biological or environmental catastrophe in the river, Hungarian officials said on Friday. Interior Minister Sandor Pinter told a news conference the spill had not affected the drinking water supply so far and government spokeswoman Anna Nagy said the food chain was safe. Hungary declared a state of emergency in three counties on Tuesday after a torrent of toxic sludge from an alumina plant tore through three villages 160 km (100 miles) west of Budapest, killing seven people and leaving dozens with vicious burns. A photograph circulated by environmental group WWF on Friday suggested the reservoir may have been leaking as far back as June. Officials at the Ajkai Timfoldgyar plant had no comment. ""Let's not even consider the pollution that got into the Danube as real pollution now,"" Pinter said. ""It will not be of an extent which would cause biological or environmental damage."" Tibor Dobson, a spokesman for disaster crews, said pH levels were around 8, a ""normal"" level, in the Danube, down from around 9 when the sludge reached the river on Thursday. ""We have not experienced any damage on the main Danube so far,"" Dobson told Reuters. Crews have sought to dilute the alkaline content of the spill."