Hungary scrambled Wednesday to contain a toxic mud spill that left four people dead and more than 100 injured in what is being described as an "ecological catastrophe" for the region around the Danube river.
"We've been working to neutralise the rivers since yesterday and we're already getting good results showing that alkaline levels in the water are falling," a spokewoman for the disaster relief services Timea Petroczi told AFP.
"We've got 500 people involved in the clean-up today. We're using high-pressure water jets to clean roads and houses."
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Four killed
Two adults and two young children were killed on Monday when the walls of a reservoir of residue at an aluminium plant in Ajka in western Hungary broke, sending a tidal wave of slightly radioactive, highly corrosive sludge through seven nearby villages.
While the death toll has not risen so far, out of 123 injured, eight people are in serious condition in hospital suffering from burns and another 53 also remain hospitalised.
Originally, six people had been feared missing, but that number has been revised downwards to three, Petroczi said.
The stinking red sludge left a path of devastation across 40 square kilometers (15.4 square miles), leading the interior ministry to declare a state of emergency in three counties.
Fears of spread
The two-metre (six-and-a-half-foot) tide of mud overturned cars, swept away possessions and has raised fears that pollution leeching from it could reach the Danube River, which courses through Croatia, Serbia, Bulgaria, Romania and Ukraine before flowing into the Black Sea.
The mud destroyed all vegetation other than trees and seeped into hundreds of houses in seven villages, leaving residents asking when they could return.
In Kolontar, one of the villages affected, the army had to build a temporary bridge to replace one that was swept away by the flood.
Petroczi confirmed the drinking water system had not been affected so far, but "as a precautionary measure, people are not allowed to use the water wells," she said.
Residents were also banned from eating any home-grown produce or from hunting or fishing in the region, she said.
A 'catastrophe'
Environment state secretary Zoltan Illes, who visited the area on Tuesday, described the accident as "an ecological catastrophe" and the worst chemical accident in the country's history.
The red mud is a toxic residue left over from aluminium production. It is slightly radioactive, highly corrosive and contains toxic heavy metals such as lead, cadmium, arsenic and chromium.
Interior Minister Sandor Pinter warned the sludge "can cause burns to the skin and blindness if it gets into your eyes."
Some of the sludge has already found its way into the Marcal river, potentially polluting the connecting Raba and Danube rivers.
But experts say that due to rain and the neutralizing agents, the Raba will suffer less damage than the Marcal.
Nevertheless, there are fears the sludge could reach the Danube, Europe's second longest river, in four or five days, said the deputy chief of the water management company for western Hungary, Sandor Toth.
"From the point of view of water management, it's a catastrophe," Toth said.
Romania's environment ministry said it was monitoring water quality round-the-clock and stressed that the level of pollutants had not crossed the acceptable limits thus far.
Officials have suggested the Hungarian Aluminium Production and Trade Company (MAL), which owns the reservoir, had stored more red sludge in the reservoir than was allowed, or that the containers had not been sufficiently fitted.
But MAL insisted it had done nothing wrong.
Nevertheless, the company has suspended all production at the plant for the time being.
Prime Minister Viktor Orban sent his condolences to the victims' families and promised a thorough investigation to find "who is responsible for this man-made catastrophe".
Environmental group Greenpeace called for MAL's managers to be punished, saying satellite imagery taken a day before the disaster showed "catastrophic cracks in the tank's walls."
Conservation group WWF said it was concerned about the long-term environmental impact.
