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elements and the calculation of tissue and organ doses following intake. They provide a mathematical platform to visualize the translocation, retention and elimination of substances within the body, considering such factors as the fractional
absorption of the material via the route of entry, uptake and residence time in various tissues and organs, chemical and physical factors such as solubility and particle
size distribution and clearance kinetics from the body. Thus, they assume paramount
importance in predicting biological consequences of intakes and understanding the
corresponding toxicity. The biokinetics of uranium is influenced by various factors
such as:
(a) Physiological characteristics of individual
(b) Age, diet, exercise and medication
(c) Environmental factors, such as temperature, moisture, sweating, etc.
Over the last century, much progress has been made in understanding uranium
behaviour in the human body with the help of data collected from:
(a) Laboratory animals such as rats, dogs and baboons exposed to uranium compounds for various experimental purposes
(b) Measurements of uranium in blood and excreta samples of human subjects who
were intravenously injected with uranium
(c) Measurements of uranium in the respiratory tract and in urine from occupationally exposed individuals
(d) Post-mortem measurements of tissues of occupationally exposed persons subject to inhalation or ingestion of uranium
(e) A general understanding of physiological processes that influence uranium
transport and storage in the body, e.g. through an appreciation of similarities
and differences in the metabolism of calcium and uranium
The major milestones of biokinetic modelling of uranium in human adults are
discussed below:
4.1 Bernard and Struxness Model (1957)
A cooperative study on distribution and excretion of uranium was conducted by the
Department of Neurosurgery, Massachusetts General Hospital and Health Physics
Division, Oak Ridge National Laboratory. Eight terminally ill brain tumour patients
were administered with uranium compounds, six were injected with UO 2 (NO 3 ) 2 ·6H 2 O
and two with UCl 4 . The removal of uranium from the blood, uranium excretion in
urine and faeces and distribution of uranium in the bone and in many samples of
tissue were measured. A model was proposed consisting of four compartments as
shown in Fig. 2 and was the first of its kind. The kidney was considered as the most
susceptible organ to radiation damage rather than the bone.
R. Mehra and S. Kaur
elements and the calculation of tissue and organ doses following intake. They provide a mathematical platform to visualize the translocation, retention and elimination of substances within the body, considering such factors as the fractional
absorption of the material via the route of entry, uptake and residence time in various tissues and organs, chemical and physical factors such as solubility and particle
size distribution and clearance kinetics from the body. Thus, they assume paramount
importance in predicting biological consequences of intakes and understanding the
corresponding toxicity. The biokinetics of uranium is influenced by various factors
such as:
(a) Physiological characteristics of individual
(b) Age, diet, exercise and medication
(c) Environmental factors, such as temperature, moisture, sweating, etc.
Over the last century, much progress has been made in understanding uranium
behaviour in the human body with the help of data collected from:
(a) Laboratory animals such as rats, dogs and baboons exposed to uranium compounds for various experimental purposes
(b) Measurements of uranium in blood and excreta samples of human subjects who
were intravenously injected with uranium
(c) Measurements of uranium in the respiratory tract and in urine from occupationally exposed individuals
(d) Post-mortem measurements of tissues of occupationally exposed persons subject to inhalation or ingestion of uranium
(e) A general understanding of physiological processes that influence uranium
transport and storage in the body, e.g. through an appreciation of similarities
and differences in the metabolism of calcium and uranium
The major milestones of biokinetic modelling of uranium in human adults are
discussed below:
4.1 Bernard and Struxness Model (1957)
A cooperative study on distribution and excretion of uranium was conducted by the
Department of Neurosurgery, Massachusetts General Hospital and Health Physics
Division, Oak Ridge National Laboratory. Eight terminally ill brain tumour patients
were administered with uranium compounds, six were injected with UO 2 (NO 3 ) 2 ·6H 2 O
and two with UCl 4 . The removal of uranium from the blood, uranium excretion in
urine and faeces and distribution of uranium in the bone and in many samples of
tissue were measured. A model was proposed consisting of four compartments as
shown in Fig. 2 and was the first of its kind. The kidney was considered as the most
susceptible organ to radiation damage rather than the bone.
R. Mehra and S. Kaur