Question: Polonium-210 was used as a homicidal agent in the well-publicized case of Alexander Litvinenko. Which decay related particle is emitted by Polonium-210 and is responsible for the adverse effects of this isotope?
Answer: The cited reference notes “Polonium-210 is a naturally occurring radioactive element that was discovered in 1898 by Marie Curie. It decays to stable lead-206 by emitting one alpha particle, with occasional excitation in the nucleus and emission of 803 keV gamma rays.” (Nathwani AC et al. Polonium-210 poisoning: a first-hand account. 2016 The Lancet 388:1075-1080)