Handling
Polonium-210 is very dangerous to handle in even milligram or microgram amounts, and special equipment and strict control is necessary. Damage arises from the complete absorption of the energy of the alpha particle into tissue. The maximum permissible body burden for ingested polonium is only 0.03 microcuries, which represents a particle weighing only 6.8 x 10-12 g. Weight for weight it is about 2.5 x 1011 times as toxic as hydrocyanic acid. The maximum allowable concentration for soluble polonium compounds in air is about 2 x 10-11 microcuries/cm3.