Ultrafine particle deposition in a realistic human airway at multiple inhalation scenarios. (29th May 2019)

• Record Type: Journal Article
• Authors: Dong, Jingliang; Shang, Yidan; Tian, Lin; Inthavong, Kiao; Qiu, Dasheng; Tu, Jiyuan
• Is Part Of: International journal for numerical methods in biomedical engineering. Volume 35:Number 7(2019)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2019-05-29
• Subjects: deposition concentration -- deposition efficiency -- respiratory airway -- ultrafine particles; Biomedical engineering -- Periodicals; Imaging systems in medicine -- Periodicals; Numerical analysis -- Periodicals; Engineering mathematics -- Periodicals; 610.28
• DOI: 10.1002/cnm.3215
• Languages: English
• ISSNs: 2040-7939

Abstract

Abstract: The scarcity of regional deposition data in distal respiratory airways represents an important challenge for current toxicology and pharmacology research. To bridge this gap, a realistic airway model extending from nasal and oral openings to distal bronchial airways with varying pathway length was built in this study. Transport and deposition characteristics of naturally inhaled ultrafine particles (UFPs) ranging from 1 to 100 nm were numerically investigated, and effects of different inhalation scenarios were considered. To enable intercase particle deposition comparison, an adjusted parameter, unified deposition enhancement factor (UDEF), was proposed for quantifying the localised deposition concentration. Results show that compartment particle deposition peaked around the ultrafine end of the considered size range, and it dropped rapidly with the increase of particle size. Different inhalation modes caused notable deposition changes in the extrathoracic region, while its effects in the TB airway are much less. For UFPs larger than 10 nm, predicted deposition efficiencies in all compartments are all at lowest levels among considered particle size range, implying UFPs ranging from 10 to 100 nm can travel through the whole respiratory airway model and escape to the alveolar region. Furthermore, high enhancement factors were observed at the vicinity of most bifurcation apexes, and more even UDEF distribution was observed from 1‐nm particle cases. While for 100‐nm cases, the deposited particles tend to concentrate at few "hot spots" (areas of high deposition concentration in relation to surrounding surfaces) with greater UDEF in the tracheobronchial airway. Abstract : A large‐scale respiratory airway model extending from nasal and oral openings to distal bronchial airways was built. In‐silico modelling of ultrafine particle exposure in the human body was conducted. Overall, regional and local deposition patterns were analysed in detail, and regional depositions in distal lobar airways are found less sensitive to the changes of inhalation mode. This study offers a promising solution for assessing population respiratory health risks with affordable and controllable costs, especially for heavily exposed occupational subgroups.