Biokinetic models Leggett model

Leggett (1992) Americium Biokinetics Model Description of the model. 

Leggett RW, Eckerman KF, Williams LR. 1993. An elementary method for implementing complex biokinetic models. Health Phys 64(3) 260-271. 

Kinetic Constants and Model Parameters in the O Flaherty Model 2-7 Residence Times in the Biokinetic Module of the IEUBK Model 2-8 Kinetic Constants and Model Parameters in the Leggett Model 2-9 Summary of Blood Slope Factors from Various Environmental Media 2-10 Genotoxicity of Lead In Vivo 2-11 Genotoxicity of Lead In Vitro... 

The Leggett Model simulates lead biokinetics in liver with two compartments the first simulates rapid uptake of lead from plasma and a relatively short removal half-life (days) for transfers to plasma and to the small intestine by biliary secretion a second compartment simulates a more gradual transfer to plasma of approximately 10% of lead uptake in liver. Different transfer rates associated with each compartment are calibrated to reproduce patterns of uptake and retention of lead observed in humans, baboons, and beagles following intravenous injection, as well as blood-to-liver concentration ratios from data on chronically exposed humans. Similarly, the Leggett Model simulates lead biokinetics in three compartments of soft tissues, representing rapid, intermediate, and slow turnover rates (without specific physiologic correlates). 

Species extrapolation. Data on both animals and humans (children and adults) describing the absorption, distribution, metabolism, and excretion of lead provide the biological basis of the biokinetic model and parameter values used in the Leggett Model. The model is calibrated to predict compartmental lead masses only for humans, both children and adults. 

Pharmacokinetic models have been developed that attempt to relate environmental levels to PbB levels (Leggett 1993 O Flaherty 1995). The Integrated Exposure Uptake Biokinetic Model (IEUBK) developed by EPA is one of the most extensive efforts to date to make population-based predictions of PbB levels based upon environmental data. The model incorporates both exposure/uptake parameters and a biokinetic component to estimate the PbB distribution in the exposed population (EPA 1994). 

Leggett RW. 1992. A generic age-specific biokinetic model for calcium-like elements. Radiat Protect Dosim 41 183-198. 

FIGURE 4.2 Biokinetic model for embedded fragments of depleted uranium. (From Leggett, R.W. and Pellmar, T.C., J. Environ. Radioact., 64, 205, 2003b. With permission.)... 

Leggett, R.W. (1994). Basis for the ICRP s age-specific biokinetic model for uranium. Health Phys. 67, 589-610. 

Leggett, R.W., Eckerman, K.F., and McGinn, C.W. (2012). Controlling intake of uranium in the workplace Applications of biokinetic modeling and occupational monitoring data, ORNL/TM-2012/14. Oak Ridge, TN Oak Ridge National Laboratory. 

Pounds, J.G., Leggett, R.W., 1998. The ICRP age-specific biokinetic model for lead validations, empirical comparisons, and explorations. Environ. Health Perspect. 106 (SuppL 6), 1505-1511. 

The Human Respiratory Tract Model Absorption into Blood 3-6. ICRP (1989) Model of Americium Biokinetics 3-7. Leggett (1992) Model of Americium Biokinetics... 

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