Environmental radioactivity

AGM2015: A worldwide v̄e flux map combining geoneutrinos from natural Uranium-238 and Thorium-232 decay in the Earth's crust and mantle as well as manmade reactor-v̄e emitted by power reactors worldwide.

Environmental radioactivity is part of the overall background radiation and is produced by radioactive materials in the human environment. While some radioisotopes, such as strontium-90 (90Sr) and technetium-99 (99Tc), are only found on Earth as a result of human activity, and some, like potassium-40 (40K), are only present due to natural processes, a few isotopes, such as tritium (3H), result from both natural processes and human activities. The concentration and location of some natural isotopes, particularly uranium-238 (238U), can be affected by human activity, such as nuclear weapons testing, which caused a global fallout, with up to 2.4 million deaths by 2020.