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Hungarian Red Sludge

What's in that stuff that pollutes the Danube ?


The red sludge in question is a waste product of the aluminium smelting industry. In 2010 it was said on the News that www.mal.hu had had the misfortune to leak a quantity of red sludge into the Danube. That gloriously famous river, the Danube, is reputed to be blue, and suddenly there was this gunky red industrial stuff spilled into it.

But let's not be too hasty about this. What was IN the red sludge? How toxic was it? At the time Greenpeace were saying there were "heavy metals" in it, but that doesn't make sense from an aluminium smelting perspective!

The fact is that the red sludge was found to contain:

* Iron oxide ... = rust

* Aluminium oxide ... = that grey stuff that comes off a non-stick pan when you give it a scrub with wire wool

* Silicon oxide ... = sand.

Now although these aren't the sorts of things you'd like to have on toast, they are hardly poisonous deadly skull-and-crossbones type chemicals. Yes, it's true, people have died because of the red sludge, and that's very sad. However, they weren't poisoned. They drowned.

There is a pollution risk, but it is not like mercuric chloride or hydrogen cyanide. The pollution risk of the red sludge is mainly because it is alkaline. It's like the sort of stuff found in a kitchen cupboard to clean the sink. You wouldn't put it in your drink, and you wouldn't put it in the fishtank, but it's not so deadly. After all, it's used on the pots and pans.

Worldwide, the aluminium industry produces a large amount of red sludge. Although the bulk is large, fortunately it is not deadly toxic. Still, aluminium is recyclable and once it's been produced it can be used time and time again. I heard that in the United States the amount of aluminium produced which is not recycled is "equivalent to throwing out the entire commercial aircraft fleet every three months". (The parallel is drawn because the aircraft are also made of aluminium). Obviously the answer is: MORE RECYCLING!

Meanwhile, heavy metals? Well, it might be possible to create a punk heavy metal version of The Blue Danube, but the metals in the stuff of this industrial spillage are not heavy. If you think titanium oxide counts, consider this: It's the inert powder in make-up. Titanium might be a heavy metal in that it would hurt if you dropped it on your foot, but it is not a heavy metal in the sense of heavy metals being toxic such as mercury, lead, and cadmium.

To sum up: Recycle more aluminium.Zyra Also, when you see a news story about a pollution incident, find out what the toxins really are. It's no good just assuming that because the stuff looks bad that it's therefore deadly.