Module 101 Properties of Uranium
The Chernobyl disaster
resulted in a graphic
reactor core fire that
burned for days.
The principal entry of uranium into the human
system is due to either inhalation or ingestion.
Inhalation occurs either from release of volatile
uranium compound or from suspension of volatile
uranium-laden aerosols. Ingestion can occur when
the uranium is introduced into water for
consumption or the food chain by plant uptake.
When uranium is either ingested or inhaled, it is
removed from the body with a biological half-life
varying between 6 and 5000 days, depending on
which organ has become contaminated. Uranium
tends to concentrate in the kidneys and the bones.
Additionally, if inhaled, the lungs are exposed.
Internal exposure to uranium is controlled by
limiting the ingestion and inhalation of this element.
These methods, along with measurement techniques,
are discussed in Module 104.
Most heavy metals, such as uranium, are toxic to
humans depending on the amount introduced into
the body. For short-term (acute) exposures, the
toxicological effects are the primary concern, and
acute exposures to significant amounts of uranium
may result in kidney damage. However, as the
enrichment of the uranium in the 235U isotope
increases, so too do the effects of radiation exposure
in relation to toxicological effects.