According to Bomb Plot Involved Deadly Chemical, “British authorities believe terror suspects arrested last week were planning to make a bomb that would include a highly toxic, easily obtained chemical called osmium tetroxide”:
‘It’s a nasty piece of work,’ said Dave Siegrist, a bioterrorism expert at the Potomac Institute for Policy Studies in Arlington, Va. ‘It irritates the eyes, lungs, nose and throat. It leads to an asthma-like death, what we call a dry-land drowning.’Scientists say if, for example, the bomb used in the 1993 World Trade Center attack had produced such fumes, they would have wiped out the first police and rescue workers on the scene.
What is Osmium?
Osmium is a chemical element in the periodic table that has the symbol Os and atomic number 76. A hard brittle blue-gray or blue-black transition metal in the platinum family, osmium is the densest natural element and is used in some alloys with platinum and iridium. Osmium is found native as an alloy in platinum ore and its tetroxide has been used to stain tissues and in fingerprinting. Alloys of osmium are employed in ballpoint pen tips, electrical contacts and in other applications where extreme durability and hardness are needed.
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Osmium (Greek osme meaning “a smell”) was discovered in 1803 by Smithson Tennant in London, England along with iridium in the residue of dissolving platinum in aqua regia.
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Osmium tetraoxide is highly toxic. Airborne concentrations of osmium as low as 10-7 g/m? can cause lung congestion, skin or eye damage.