The Litvinenko story has taken a strange twist with reports of a Mercury Trail that covers Moscow and London and, apparently, overlaps the Polonium-210 trail associated with Litvinenko’s bizzare death last month.

The prosecutor general’s office said traces of evaporated mercury had been found in cars, flats, cottages and offices in both Moscow and London.

It did not say who owned or used the properties.

Significant amounts of polonium 210 were found in Litvinenko’s body after his death, but it was unclear what role mercury could have played.

Under the theory that the Polonium-210 in the Litvinenko incident, which has a trail spanning three countries and is much larger than would be required to kill a single man, is associated with a smuggling ring the addition of a Mercury trail could be very disturbing. We don’t know what form the Mercury is in or its relationship with Polonium. But one of the uses of Mercury is in small explosives, like detonator caps:

Mercury fulminate (Hg(ONC)2) is a primary explosive. It is highly sensitive to friction and shock. It is mainly used in blasting caps. It is also known as mercury(II) cyanate.

Today mercury fulminate tends to be replaced by other primary explosives which are less toxic and more stable in time: lead azide, lead styphnate and tetrazene derivatives.

One only needs to recall how small a dose Litvinenko ingested – equivalent to a grain of salt – to ponder how an explosive like Mercury Fulminate could be used to create small dirty bombs of Polonium 210. The question of how to disperese the Polonium 210 in order to expose a lot of people is answered in a frightenly easy way – fireworks

(b) The State Fire Marshal shall adopt reasonable regulations, in accordance with chapter 54, for the granting of permits for supervised displays of fireworks or for the indoor use of pyrotechnics, sparklers and fountains for special effects by municipalities, fair associations, amusement parks, other organizations or groups of individuals or artisans in pursuit of their trade.

…

In an aerial bomb, no salute, report or maroon may be used that is composed of a formula of chlorate of potash, sulphur, black needle antimony and dark aluminum. Formulas that may be used in a salute, report or maroon are as follows: (A) Perchlorate of potash, black needle antimony and dark aluminum, and (B) perchlorate of potash, dark aluminum and sulphur. No high explosive such as dynamite, fulminate of mercury or other stimulator for detonating shall be used in any aerial bomb or other pyrotechnics.

Clealry, the need to make Mercury Fulminate illegal in firework construction means it is possible to use it in firework construction. Why would one use such an unstable detonator? Why would someone use Polonium-210 to kill Litvinenko. But it might be as simple as what materials draw attention or which ones could be accessed on the black market.

The reality is the lethality of Polonium-210 means one only requires small explosions to disperse the material if it is in a fine granular form. A sugar packet’s worth of Polonium-210 is not very much to disperse but it could kill tens of thousands. I am not sure if one could make a small firecracker sized version of a Polonium dirty bomb, but if it is possible it would be hard to detect amongst all the other activities one sees around New Years Eve. I am speculating on all of this of course, but the pattern of evidence and timing seems too coincidental. One thing that does draw crowds around this time of year are New Years Eve celebrations – and their fireworks.