Poisoning has gone high tech since Ukrainian President Viktor Yushchenko was nearly done in by Dioxin.
Former KGB agent and Putin critic, Alexander Litvinenko, survived the sushi at Itsu in Piccadilly, but succumbed to polonium 210. Guardian Unlimited reports that Russia has a thriving black market trade in radioactive material.
Poison is popular for Putin critics. Even journalist, Anna Politkovskaya, was poisoned before being shot while leaving her apartment.

This is a very intelligent one! Yushchenko, Politkovskaya, Litvinenko… who will be the next one to be poisoned!?… Why not… Great job, Bok!