THE DETERMINATION OF TECHNETIUM-99 IN SOIL, SILT, SAND AND SEDIMENT BY ICP-MS USING ISOTOPICALLY ENRICHED RHENIUM AS A YIELD MONITOR

摘要

Technetium, atomic number 43, has no stable isotopes. The majority of technetium in the environment originates from anthropogenic sources including nuclear weapons testing, medical applications and nuclear power generation. Technetium-99 is a pure β emitter (E_(max) = 294keV) with a high fission yield from U-235 (6%) and long half-life (2.115 x 10~5years). Today, the greatest potential for the release of technetium-99 is in the reprocessing of spent nuclear fuel. Under aerobic conditions technetium exists as the pertechnatate ion (TCO4). This anionic species is highly mobile in the environment and therefore may be a significant contributor to the committed radiation dose of the human population.