Mining Metals Using Plants and Trees?

elroySF writes "An MIT Technology Review article says "...Scientists reported Monday that they have bioengineered a plant capable of absorbing arsenic from soil and sequenced the complete set of genes for a microbe that can remove heavy metals from water." It goes on to say "...Some scientists even see the day when trees and grasses will be used to mine metals and minerals without disturbing the soil." " We had a story about this a while back.

Comments

Re:Gotta love those MIT brains...

[Anonymous Coward]

Make all the jokes you want, but it's all about a concentration process.

Yes, you pump arsenic from a disposal site, but the arsenic in that waste will probably be low concentration (just ppm in solids is considered bad).

Imagine that the plant sucks up *all* the arsenic from the soil, and *just* the arsenic. Thousands of tons of crap, which contain a few hundred pounds of arsenic, all of which goes into leaves. You then harvest the plants, put them into compost, shovel out a nice barrel full of arsenic into a secured container for burial, and have your nice thousands of tons of crap cleaned of arsenic. All the arsenic is still there, it's just become a smaller, more manageable problem.

Arsenic is an *element* (although what most people consider arsenic is Arsenolite, As2O3. Arsenic as As metal is pretty rare to find naturally), until you get that whole alchemy thing going and you transmute it into iron, there are no decent forms of arsenic that are completely safe. Everything is about concentration and containment.

Re:Already happens?

[GigsVT]

Cyanide facts:

There are 0.6 mg/g hydrogen cyanide (HCN) in dried apple seeds. Cite

Natural cyanide is called Amygdalin, chemically it is bonded to a glucose and readily converts to hydrogen cyanide in the body. Herbal places sell it as a miracle cure for cancer. "Amygdalin Tablets & Ampoules www.cytopharma.com" This was an ad that came up during a google search related to cyanide.

50 to 100 mg of cyanide is a lethal dose. Cite

This is about a half-cup to a full cup (80-160grams) of dried apple seeds.

An interesting site on cyanide.

Related:
Smoking of cigarettes commonly releases cyanide. Tobacco smokers have a mean blood cyanide level of 0.4 mcg/cc, which is 2.5 times greater than the level in nonsmokers. Cite