Comparing effects of inhaled particles across rodent test systems and between rodent test systems and @entity1 is a key obstacle to the interpretation of common toxicological test systems for @entity1 risk assessment. These comparisons, correlation with effects and prediction of effects, are best conducted using measures of tissue dose in the respiratory tract. Differences in lung geometry, physiology and the characteristics of ventilation can give rise to differences in the regional deposition of particles in the lung in these species. Differences in regional lung tissue doses cannot currently be measured experimentally. Regional lung tissue dosimetry can however be predicted using models developed for @entity35 , monkeys, and @entity1 . A computational model of particle respiratory tract deposition and clearance was developed for BALB/c and B6C3F1 @entity19 , creating a cross-species suite of available models for particle dosimetry in the lung. Airflow and particle transport equations were solved throughout the respiratory tract of these @entity19 strains to obtain temporal and spatial concentration of inhaled particles from which deposition fractions were determined. Particle inhalability (Inhalable fraction, IF) and upper respiratory tract (URT) deposition were directly related to particle diffusive and inertial properties. Measurements of the retained mass at several post-exposure times following exposure to @entity1933 nanoparticles, micro- and nanoscale @entity12200 , and nanoscale @entity575 particles were used to calibrate and verify model predictions of total lung dose. Interstrain ( @entity19 ) and interspecies ( @entity19 , @entity35 and @entity1 ) differences in particle inhalability, fractional deposition and tissue dosimetry are described for ultrafine, fine and coarse particles.

Computational modeling of nanoscale and microscale particle deposition, retention and dosimetry in the XXXX respiratory tract.

@entity1 :: ('9606', 'Species') :: ['humans', 'human'] @entity575 :: ('MESH:D012834', 'Chemical') :: ['silver'] @entity19 :: ('10090', 'Species') :: ['mice', 'mouse'] @entity12200 :: ('MESH:C069837', 'Chemical') :: ['C60 fullerene'] @entity1933 :: ('MESH:C000499', 'Chemical') :: ['iron oxide'] @entity35 :: ('10116', 'Species') :: ['rat', 'rats']
@entity19 :: (10090,Species) :: ['mouse']
