New pictures from Hungary show the broken wall of a reservoir after it burst, spilling a torrent of toxic sludge from an alumina plant.
The environmental group WWF has suggested it may have been leaking as far back as June. It claims to have evidence showing damage outside the facility.
Since Monday’s leak, seven people died and dozens have been left with vicious burns. There are still no estimates of the financial damage or likely insurance payouts.
But fears that downstream, the once blue Danube may turn red with sludge have not been borne out. Officials say alkaline levels in Europe’s second largest river are “normal” and there’s no risk of a biological or environmental disaster.
The Hungarian government said the spill had not affected drinking water supplies or the food chain.
It has requested aid from the EU, asking for up to five environmental experts to help with the aftermath.
All life has been killed in the smaller Marcal river, and there’ve been reports of fish dying in two other Danube tributaries.
Greenpeace has accused the authorities of underestimating the ecological dangers, and says its own tests found high levels of heavy metals.
For those in the worst-hit area, the biggest challenge is the clean-up.
Even the rescue of a cat provided little light relief. It was not expected to survive.