Alpha-recoil atoms of plutonium in the environment

The -recoil effect of²³⁹Pu has been observed in environmental samples and theN ₅ ^P /N₅ ratio in these samples has been calculated. This ratio in atmospheric samples is in the range between 10^–5 and 10^–4 (atom/atom). For other contemporary terrestrial samples it is in the range between 10^–7 and 10^–6 (atom/atom), while that of uranium mineral is about 10^–10 (atom/atom). The results further explain the radioactive fallout contamination of our environment by uranium and plutonium isotopes.