Plutonium

Plutonium is a chemical element (atomic number 94). It's not found in nature but is created when uranium undergoes fission in a nuclear reactor.
Plutonium is highly radioactive and inhaling even a small amount will almost certainly result in the development of a cancer. Exposure to even small amounts of plutonium can result in radiation sickness and it's toxic in doses as low as the milligram of plutonium to kilogram of body tissue level from heavy metal poisoning alone.
Plutonium at Wikipedia
Category:Chemistry
Category:Toxins