text: Applications A single gram of 210Po generates 140 watts of power. Because it emits many alpha particles, which are stopped within a very short distance in dense media and release their energy, 210Po has been used as a lightweight heat source to power thermoelectric cells in artificial satellites; for instance, a 210Po heat source was also in each of the Lunokhod rovers deployed on the surface of the Moon, to keep their internal components warm during the lunar nights. Some anti-static brushes, used for neutralizing static electricity on materials like photographic film, contain a few microcuries of 210Po as a source of charged particles. 210Po was also used in initiators for atomic bombs through the (α,n) reaction with beryllium. Small neutron sources reliant on the (α,n) reaction also usually use polonium as a convenient source of alpha particles due to its comparatively low gamma emissions (allowing easy shielding) and high specific activity.
  Hazards
  210Po is extremely toxic; it and other polonium isotopes are some of the most radiotoxic substances to humans. With one microgram of 210Po being more than enough to kill the average adult, it is 250,000 times more toxic than hydrogen cyanide by weight. One gram of 210Po would hypothetically be enough to kill 50 million people and sicken another 50 million. This is a consequence of its ionizing alpha radiation, as alpha particles are especially damaging to organic tissues inside the body. However, 210Po does not pose a radiation hazard when contained outside the body. The alpha particles it produces cannot penetrate the outer layer of dead skin cells.