Abstract:
Introduction In 2018, the World Health Organization recognized air pollution as a risk factor for noncommunicable diseases (NCD). Air pollutants, such as ultrafine particles (UFP), can penetrate deep into the lungs and enter the bloodstream, causing cardiovascular (coronary heart disease), cerebrovascular (stroke) and respiratory diseases. The determination of lung deposited surface area (LDSA) of UFP is of high interest for exposure assessment, as it reflects the concept that particle surface area available in the lung is a relevant exposure metric. LDSA has been proposed as a critical predictor for health outcomes from aerosol exposure, as it appears to be one of the most relevant physical metrics for evaluating exposure to particles. Aim of the study To analyze the long-term (2013-2020) spatial-temporal characteristics of concentration of total LDSA in Chernivtsi city, Ukraine. Material and methods UFP measurements were carried out using a Scanning Mobility Particle Sizer (SMPS). The sampling site was an urban background station located in the center of Chernivtsi (Ukraine). The measurement period included a full eight years (2013-2020). Particle number concentration (PNC) distributions obtained from SMPS measurements were used to calculate total LDSA values according to the International Commission on Radiological Protection (ICRP) deposition model. In this model applied to divide the respiratory tract into three main regions, including the head/throat (HA), tracheobronchial (TB), and alveolar (ALV) regions. Descriptive statistical analysis was applied to evaluate annual mean concentrations, temporal variability, and relationships between particle size fractions and LDSA levels. Results The annual range of concentration of total LDSA was between 100 and 200 μm2/cm3. There are higher concentrations in Eastern Europe. The diel, weekly, and seasonal variability in total LDSA shows significant differences at different types. The PNC in the Aitken and accumulation modes are mainly associated with the total LDSA concentration. The main proportion of LDSA is attributed to the ALV fractions. Conclusion Measurements of total LDSA concentrations at different types of locations highlight the importance of considering LDSA as an additional indicator of air quality due to its possible association with health risks and the development of chronic noncommunicable diseases. The evaluation of total LDSA in different regions of the respiratory tract, including HA, TB, and ALV as an exposure metric in time series of epidemiological studies should be further investigated.
