A mathematical model of bronchial absorption of vapors in the human lung and its significance in pharmacokinetic modeling.
This work formulates a model description of moderately soluble gas and vapor uptake in the bronchial region of the lung during initial inhalation exposure. The mass transport problem is solved using an iterative-analytical approach in which inhaled chemical is partitioned to alveolar blood-gas exchange, bronchial wall absorption, and exhalation. Results of 109 simulations allowed regression analysis to provide simple algebraic equations to describe the fraction of total inhaled mass taken up by the two alternative absorption pathways. These fractions are dependent on the chemical's solubility and liquid diffusivity. The derived relationships are then used in a modified physiologically based pharmacokinetic (PBPK) model which accounts for bronchial uptake. The results are compared to identical results from a traditional (unmodified) PBPK model to draw conclusions concerning the effect of bronchial uptake on systemic chemical distribution in addition to elevated bronchial tissue concentrations.
Shelley
M L
ML
Department of Engineering and Environmental Management, Air Force Institute of Technology, Wright-Patterson Air Force Base, OH 45433, USA.
Harris
R L
RL
Boehlecke
B A
BA
D000042:Absorption; D000280:Administration, Inhalation; D001692:Biological Transport; D001980:Bronchi / Q000378:metabolism*; D005740:Gases / Q000493:pharmacokinetics*; D006801:Humans; D008168:Lung / Q000378:metabolism*; D008432:Mathematical Computing; D008954:Models, Biological; D010599:Pharmacokinetics
D005740:Gases