In 2010, after weeks of heavy rain, the containment unit at Ajka in Western Hungary had collapsed causing nearly a million cubic metres of toxic sludge to come pouring into the Torna-Marcal river system, flowing by the plains and ending up in the Danube.

The immediate reaction to the event was of panic as this red mud is highly alkaline, containing toxic metals like chromium and vanadium. Moreover, since such massive amounts of the stuff had never been released into the environment before, no one knew what the consequences would be on the people and wildlife.

Thankfully, a study conducted by the Environmental Science: Processes & Impacts revealed that there is hardly any trace of the toxic material left in the Tornar and Marcal rivers.

The Hungarian government played an important role in this as they took prompt steps to contain the situation spending around €127 million in the process. The mud was trudged out of the river and the plains and steps were taken to douse the alkaline mud with acid near the source of the spill.

Moreover, by the time the red mud river ultimately landed in the might Danube River, it got too diluted to cause any harm to anyone.

A team of geologists had travelled to these areas to mark the pollution hotspots at the time of the spill and there were many with alarming toxic levels. However, re-testing those same spots revealed that there hardly any trace of red mud.