<p>Aerosol particles, as the significant irritants to the respiratory tracts and lungs, have been explored, especially for drug aerosol delivery and deposition. However, inhalation risk evaluation based on the real-life measurements to bioaerosols is lacking. This study developed a pediatric airway model from oral cavity to G0-G7 bronchi and constricted the left G1-G3 bronchi for asthmatic children. Based on the measured concentration and size distributions of fungal aerosols from 30 homes, the Rosin–Rammler distribution function was adopted to simulate the mass fractions of aerosols under different size ranges. In addition, the airflow and deposition characteristics were explored. Results showed the total deposition fraction in the airways of asthmatic children was higher, about 44%, at an inspiratory flow rate of 10L/min. Constriction of the left G1-G3 bronchi led to lower deposition fraction of 2.1% in the right G4-G7 bronchi but higher value in the left side (5.8%). Increasing from 5 L/min to 10 L/min and 15 L/min increased significantly the deposition fractions in the oropharyngeal regions, about 13.3%, 20.7%, and 28.7%, respectively. The seasonal differences showed the highest deposition fraction of 52.1% in transient season, due to the size distribution differences. This study demonstrates a better understanding of the effects of airway constriction on dynamic flow field and aerosol deposition in asthmatic children, and the inhalation and deposition characteristic to fungal aerosols in daily exposure, which differs from typical environmental exposure. The work provides practical implications of improving airway modeling simulation, and developing the respective risk control for indoor microorganism exposure.</p>

错误:搜索内容不能为空,请输入英文关键词
错误:关键词超出字数限制,请精简
高级检索

Modeling fungal aerosol deposition in the upper bronchi of asthmatic children based on measured concentration and size distribution in homes

  • Chenqiu Du,
  • Mengyu Xu,
  • Jiqiao Chen,
  • Emmanuel Essah,
  • Min Chen,
  • Juan Wang

摘要

Aerosol particles, as the significant irritants to the respiratory tracts and lungs, have been explored, especially for drug aerosol delivery and deposition. However, inhalation risk evaluation based on the real-life measurements to bioaerosols is lacking. This study developed a pediatric airway model from oral cavity to G0-G7 bronchi and constricted the left G1-G3 bronchi for asthmatic children. Based on the measured concentration and size distributions of fungal aerosols from 30 homes, the Rosin–Rammler distribution function was adopted to simulate the mass fractions of aerosols under different size ranges. In addition, the airflow and deposition characteristics were explored. Results showed the total deposition fraction in the airways of asthmatic children was higher, about 44%, at an inspiratory flow rate of 10L/min. Constriction of the left G1-G3 bronchi led to lower deposition fraction of 2.1% in the right G4-G7 bronchi but higher value in the left side (5.8%). Increasing from 5 L/min to 10 L/min and 15 L/min increased significantly the deposition fractions in the oropharyngeal regions, about 13.3%, 20.7%, and 28.7%, respectively. The seasonal differences showed the highest deposition fraction of 52.1% in transient season, due to the size distribution differences. This study demonstrates a better understanding of the effects of airway constriction on dynamic flow field and aerosol deposition in asthmatic children, and the inhalation and deposition characteristic to fungal aerosols in daily exposure, which differs from typical environmental exposure. The work provides practical implications of improving airway modeling simulation, and developing the respective risk control for indoor microorganism exposure.