Plutonium is known to be the most carcinogenic or cancer producing substance on earth and it is man made. Plutonium also lodges in the testicle where it can both damage the genes of future generations and it can induce testicular cancer. It freely crosses the placenta where like the drug thalidomide, it can damage a genetically normal embryo, to produce a deformed baby. Lung cancer has been observed in animal tests. Plutonium travels from the lungs to the blood and lymph systems.
Soluble plutonium enters the blood quickly and deposits on bone surfaces and in the liver.
Bone and liver cancers can result, because plutonium is retained in these tissues for long periods. Workers at a DOE facility in Colorado were shown to have increased cases of brain cancer from Plutonium exposure. Once plutonium has been inhaled, there is nothing that medical science can do to reduce the risk of lung cancer. Tritium is a radioactive gas. It is an isotope of the gas hydrogen.