An ecological disaster happened recently in Hungary(near Kolontár), after a dam that was holding big amounts of toxic sludge ruptured.
I’m concerned about what could happen with the surrounding areas, because the localities that were hit the hardest are anyway compromised and authorities are already evacuating the population. 5 have died. There’s also the danger of the sludge getting in the Danube.
The sludge is very dangerous because of its composition:
How does the sludge get produced and how could it escape?
When aluminium is extracted from bauxite via the so-called Bayer process, red sludge forms as a by-product. The sludge is normally kept in large reservoirs where its fluid and solid components separate into water and mud.
What caused the accident is yet unclear, but it is likely that heavy rain has caused the dam containing the reservoir to break.
It is also possible that the reservoir was just not large or strong enough to hold the sludge it was filled with.
What is the chemical composition of the sludge?
It contains mainly fluoride, sulphate and aluminate, but also chrome, nickel, manganese and heavy metals such as lead. Its arsenic concentration is at least a hundred times above the allowed threshold for drinking water.
How might contact with the toxic sludge affect human health?
The most dangerous thing about the stuff is that it is – to put it simply – a dilute solution of sodium hydroxide with an extremely alkaline pH value, between 11 and 12. This means it cauterizes eyes and skin, and attacks the lung when moist aerosols are inhaled.
Have similar chemical accidents happened in the past?
Ten years ago, large amounts of cyanide and heavy metals escaped from the waste reservoir of a Rumanian gold mine, contaminating rivers, including the Danube, and killing large quantities of fish. A similar disaster, also connected to ore processing, happened in 1998 in Spain when the waste reservoir at the Los Frailes mine ruptured and 5 million cubic meters of contaminated water rushed into the Guadiamar River near Seville.
I also heard about an accident in Romania with a man that fell into a lake of this kind of caustic sludge. He was melted.
I can’t really find my words, but I imagine the situation of the people from those affected areas. I also feel bad for the nature…