Abstract
Objectives
The aim of this study was to provide particle number and mass deposition rates of submicron particles in the human airways as inputs for toxicology and other areas of aerosol science.
Methods
Scanning Mobility Particle Spectrometer was used to measure the number concentrations and size distributions of the ultrafine urban particles during summer and winter in Budapest. The Stochastic Lung Model (SLM) was applied to calculate number and mass deposition rates of the inhaled particles in different anatomical regions of the airways.
Results
Our calculations revealed that for the selected days in summer and winter with PM10 values below the health limit 4.7 and 18.4 billion particles deposited in the bronchial region of the lungs. The deposition in the acinar region of the lung was even higher, 8.3 billion particles for the summer day, and 33.8 billion particles for winter day.
Conclusions
Our results clearly demonstrate that large daily numbers of urban UFPs are deposited in the respiratory tract, which may play a key role in the health effects of particulate matter (PM) inhalation. Present results, connecting the ambient exposure parameters with the local burden of the airway epithelium, can be useful inputs of in vitro cell culture experiments. By the combination of urban UFP monitoring and numerical modeling of particle deposition with toxicological studies, the health risks of urban aerosols could be better assessed. The use of UFP data in addition to PM10 and PM2.5 in the epidemiological studies would also be indicated.
Disclosure statement
The authors report no conflicts of interest.