Particle deposition in children's lungs: theory and experiment.
A mathematical model of inhaled aerosol particle deposition for children is presented and validated with data from two published experimental studies. The model accurately predicts deposition fraction (DF) in children as a function of particle size for particles in the size range 1-3 microns for both sedentary and exercise breathing conditions. When the experimental data are grouped according to age, the model is able to predict age-dependent trends in DF at the studied particle sizes under sedentary breathing conditions. The model predicts that when ventilatory conditions are held constant, age-dependent changes in morphology result in decreasing DF with age; however, under realistic conditions these changes may be masked by age-dependent changes in ventilation. Despite the fact that mean DF differs significantly from adult values only in children younger than 9, the model predicted that dose-per-surface area may still be greater in children due to smaller lung sizes.
Isaacs
Kristin K
KK
Experimental Toxicology Division, National Health and Environmental Effects Research Laboratory, United States Environmental Protection Agency, Research Triangle Park, North Carolina 27711, USA.
Martonen
Ted B
TB
D000293:Adolescent; D000328:Adult; D000336:Aerosols / Q000008:administration & dosage / Q000493:pharmacokinetics*; D000367:Age Factors; D000465:Algorithms; D001980:Bronchi / Q000033:anatomy & histology; D002648:Child; D003198:Computer Simulation; D005544:Forecasting; D006801:Humans; D001239:Inhalation / Q000502:physiology; D008168:Lung / Q000033:anatomy & histology / Q000378:metabolism*; D008954:Models, Biological; D010316:Particle Size; D005082:Physical Exertion / Q000502:physiology; D011650:Pulmonary Alveoli / Q000033:anatomy & histology; D015203:Reproducibility of Results; D012119:Respiration; D013990:Tidal Volume / Q000502:physiology; D014132:Trachea / Q000033:anatomy & histology
D000336:Aerosols