Original URL: http://www.theregister.co.uk/2011/02/14/sheep_eat_tnt/

Latest boffinry: Feeding TNT to sheep

There's a good reason, honest

By Lewis Page

Posted in Science, 14th February 2011 10:22 GMT

Stateside boffins are diligently getting a small number of laboratory sheep to eat as much TNT as possible.

One should point out straight away that this will not - or ought not to, anyway - involve any sheep then exploding in a sequence of fearful fleecy detonations and spattering the landscape with woolly fluff and raw mutton. This is not some kind of crazed attempt to create instant-self-barbecuing lamb or similar. In fact it seems that the guts of a sheep, capable of digesting various things which would prove fatal to lesser species such as cows or humans, can break down trinitrotoluenes - TNT - into harmless residues without any ill effects on the animal.

Probably the world's top expert on feeding sheep explosives is toxicology prof A Morrie Craig. He originally discovered the amazing powers of the ovine gut while struggling with the scourge of tansy ragwort, a poisonous plant which is fatal to cattle or horses. Sheep, however, can chow down on the deadly weed without trouble, protected by a certain anaerobic bacterium living in their digestive tract.

Meanwhile the US military has on its books vast tracts of land, which in many cases it has carelessly polluted with TNT - as for instance by firing artillery shells into the ground, or manufacturing them nearby or what have you. The explosive residue won't catch fire or blow up in the concentrations found, and isn't a health risk simply by being present, but it is seriously toxic to humans if it gets into food or water supplies. Thus the land can't be sold off and re-used for farming etc until the TNT can be got rid of somehow.

Craig's plan is a simple one: plant the ground with grasses chosen to draw out the explosives, and unleash the ovine chemical cleanup crew to guzzle the TNT-laden greenery as it sprouts. After three years or so, he estimates, the concentration in the soil should be down to such levels that the ground would then be safe for normal use.

In the meantime you could still eat the TNT-fed sheep, as the toxic explosive can't enter their system: it is broken down on entry.

We learn from Popular Science the other day that Craig "is testing the grazers on soil from a military base", with a view to putting his ideas into action. Interested readers may also care to cast an eye over the prof's seminal 2004 paper Anaerobic transformation of 2,4,6-TNT by bovine ruminal microbes.

Obviously the idea of TNT-fed sheep has a certain quiet beauty of its own, even without the benefit of land salvaged and toxins cleansed. We might all wish Professor Craig well with his plans and hope they come to immediate fruition.

We can't help noting though that Craig has been studying the practical application of the bomb-busting ovine belly microbes since the 1980s, and trying to apply them to TNT cleanup since at least 2002. It may be a while yet before sheep are routinely making land where cattle or horses may safely graze. ®