The primary hazard when working with technetium is inhalation of dust; such radioactive contamination in the lungs can pose a significant cancer risk.

[citation needed] Due to its high fission yield, relatively long half-life, and mobility in the environment, technetium-99 is one of the more significant components of nuclear waste.

Measured in becquerels per amount of spent fuel, it is the dominant producer of radiation in the period from about 104 to 106 years after the creation of the nuclear waste.

[2] The next shortest-lived fission product is samarium-151 with a half-life of 90 years, though a number of actinides produced by neutron capture have half-lives in the intermediate range.

[3] The long half-life of technetium-99 and its ability to form an anionic species make it (along with 129I) a major concern when considering long-term disposal of high-level radioactive waste.

Given the relatively high market value of ruthenium[12] and the particularly undesirable properties of technetium, this type of nuclear transmutation appears particularly promising.