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© Springer Nature Switzerland AG 2020
D. K. Gupta, C. Walther (eds.), Uranium in Plants and the Environment,
Radionuclides and Heavy Metals in the Environment,
https://doi.org/10.1007/978-3-030-14961-1_11
Biokinetic Modelling and Risk Assessment
of Uranium in Humans
Rohit Mehra and Sarabjot Kaur
Abstract The past few decades have seen substantial experimental and modelling
studies addressing the biokinetics of uranium in mammals. Various systemic models
have been developed. The degree of absorption of uranium from the gastrointestinal
tract is of particular importance and is controlled by the solubility of the uranium
compound ingested, previous food consumption and the concomitant administration
of oxidizing agents. After entering the plasma, the uranyl ion becomes complexed
with bicarbonate, citrate anions and proteins and is dispersed in body tissues. Uranium
may then be reabsorbed from various soft tissues, liver, skeleton and kidneys and
redeposited or excreted via urine, faeces and hair. The multiple established health
effects of uranium ingestion relate to both its chemical and radiological toxicity.
Organ-specific and age-adjusted annual effective doses provide insights into possible
biomarkers of uranium toxicity in humans. A systematic case study has been carried
out in the high-risk-prone area of the Malwa belt of Punjab, India, both estimating the
concentrations of uranium in groundwater and evaluating the associated toxicity.
Keywords Uranium biokinetic models · Hazard quotient · Lifetime average daily
dose · Age-adjusted dose · Organ-specific dose · Transfer coefficients
1 Background
Uranium is present in almost all rocks, soils, surface waters and groundwater as a
mix of three isotopes,
238
U (99.2742%),
235
U (0.7204%) and
234
U (0.0054%), with
half-lives of 4.47 × 10
9
, 7.04 × 10
8
and 2.46 × 10
5
years, respectively. In addition,
other uranium isotopes (
236
U and
233
U) are released into the environment as a result
of various anthropogenic activities, including mining and the production and use of
phosphate fertilizers.
R. Mehra (*) · S. Kaur
Environment Monitoring and Assessment Laboratory, Department of Physics,
Dr. B. R. Ambedkar National Institute of Technology, Jalandhar, Punjab, India
e-mail: mehrar@nitj.ac.in
© Springer Nature Switzerland AG 2020
D. K. Gupta, C. Walther (eds.), Uranium in Plants and the Environment,
Radionuclides and Heavy Metals in the Environment,
https://doi.org/10.1007/978-3-030-14961-1_11
Biokinetic Modelling and Risk Assessment
of Uranium in Humans
Rohit Mehra and Sarabjot Kaur
Abstract The past few decades have seen substantial experimental and modelling
studies addressing the biokinetics of uranium in mammals. Various systemic models
have been developed. The degree of absorption of uranium from the gastrointestinal
tract is of particular importance and is controlled by the solubility of the uranium
compound ingested, previous food consumption and the concomitant administration
of oxidizing agents. After entering the plasma, the uranyl ion becomes complexed
with bicarbonate, citrate anions and proteins and is dispersed in body tissues. Uranium
may then be reabsorbed from various soft tissues, liver, skeleton and kidneys and
redeposited or excreted via urine, faeces and hair. The multiple established health
effects of uranium ingestion relate to both its chemical and radiological toxicity.
Organ-specific and age-adjusted annual effective doses provide insights into possible
biomarkers of uranium toxicity in humans. A systematic case study has been carried
out in the high-risk-prone area of the Malwa belt of Punjab, India, both estimating the
concentrations of uranium in groundwater and evaluating the associated toxicity.
Keywords Uranium biokinetic models · Hazard quotient · Lifetime average daily
dose · Age-adjusted dose · Organ-specific dose · Transfer coefficients
1 Background
Uranium is present in almost all rocks, soils, surface waters and groundwater as a
mix of three isotopes,
238
U (99.2742%),
235
U (0.7204%) and
234
U (0.0054%), with
half-lives of 4.47 × 10
9
, 7.04 × 10
8
and 2.46 × 10
5
years, respectively. In addition,
other uranium isotopes (
236
U and
233
U) are released into the environment as a result
of various anthropogenic activities, including mining and the production and use of
phosphate fertilizers.
R. Mehra (*) · S. Kaur
Environment Monitoring and Assessment Laboratory, Department of Physics,
Dr. B. R. Ambedkar National Institute of Technology, Jalandhar, Punjab, India
e-mail: mehrar@nitj.ac.in