Quantification of Size Segregated Particulate Matter Deposition in Human Airways
21 Dec 2018-Vol. 05, Iss: 04, pp 15-22
TL;DR: PM10 has a higher deposition in the head region whereas PM2.5 and PM1 deposition is higher in the TB and pulmonary regions, which indicates that PM deposition inside lungs is influenced by its size and several other deposition mechanisms viz. inertial impaction, sedimentation, diffusion and interception.
Abstract: Background: Air pollution has become a significant concern in both urban and rural sectors due to its catastrophic effect on human health and the environment. Particulate matter (PM) is crucial among criteria pollutants and is well correlated with human mortality and morbidity. Based on aerodynamic size, PM is classified into coarse (PM10) and fine (PM2.5 and PM1). A recent study by World Health Organization showed that PM has caused 7 million premature deaths globally. Also, the International Agency for Research on Cancer (IARC) identified PM as carcinogenic as it is directly related to lung cancer. Human airway is the primary pathway for PM to enter the human body. Hence the study on coarse and fine PM deposition in the human respiratory tract is essential for health risk assessments. Materials and Methods: Hourly measurements of PM10, PM2.5 and PM1 are measured during a winter using Grimm aerosol spectrometer near an arterial roadside in Chennai city of Tamil Nadu, India. PM deposition in the human airway is investigated using the Multiple-Path Particle Deposition Model (MPPD) version 3.04. In MPPD model, the stochastic structure which depicts the real human lung is considered. The deposition in MPPD model is assessed for three size fractions, i.e. PM10, PM2.5 and PM1 under different breathing scenarios viz. nasal, oral, and oronasal. Results: Highest total deposited mass rate obtained from the MPPD model for PM10, PM2.5, and PM1 are 942 ng min-1, 345 ng min-1, and 104 ng min-1, respectively. The maximum deposited mass rate is also assessed in the head (PM10 = 904 ng min-1; PM2.5 = 244 ng min-1; PM1 = 57 ng min-1), tracheobronchial (PM10 = 284 ng min-1; PM2.5 = 60 ng min-1; PM1 = 24 ng min-1) and pulmonary (PM10 = 32 ng min-1; PM2.5 = 89 ng min-1; PM1 = 27 ng min-1) regions. In the head region, maximum deposition is caused by nasal breathing; whereas, tracheobronchial (TB) and pulmonary regions, the oral breathing leads to higher deposition. Results also showed that for all PM sizes the lobe wise depositions are in the following order: right upper > left lower > left upper > right middle > right lower. Further, the airway clearance results indicated that PM removal is faster in the TB region than the alveolar region. Conclusion: PM10 has a higher deposition in the head region whereas PM2.5 and PM1 deposition is higher in the TB and pulmonary regions. This indicates that PM deposition inside lungs is influenced by its size and several other deposition mechanisms viz. inertial impaction, sedimentation, diffusion and interception. Further, this study results can be utilized for assessing health risks such as oxidative potential and toxicity of deposited PM.
Citations
More filters
TL;DR: Estimation of inhalation doses for different PM mass/number size fractions in indoor air of residential homes and the deposition (total, regional and lobar) in human respiratory tract for both newborn children and mothers showed that 3-month old infants exhibited 4-fold higher inhalations doses than their mothers.
62 citations
TL;DR: In this article, a comprehensive literature search was conducted from January until February 2021 using the PubMed, Scopus, Web of Science, Google Scholar and Cochrane Library databases, and 14 articles were included based on the inclusion and exclusion criteria.
Abstract: Air pollution is associated with inflammation and oxidative stress, which predispose to several chronic diseases in human. Emerging evidence suggests that the severity and progression of osteoporosis are directly associated with inflammation induced by air pollutants like particulate matter (PM). This systematic review examined the relationship between PM and bone health or fractures. A comprehensive literature search was conducted from January until February 2021 using the PubMed, Scopus, Web of Science, Google Scholar and Cochrane Library databases. Human cross-sectional, cohort and case-control studies were considered. Of the 1500 papers identified, 14 articles were included based on the inclusion and exclusion criteria. The air pollution index investigated by most studies were PM2.5 and PM10. Current studies demonstrated inconsistent associations between PM and osteoporosis risk or fractures, which may partly due to the heterogeneity in subjects' characteristics, study design and analysis. In conclusion, there is an inconclusive relationship between osteoporosis risk and fracture and PM exposures which require further validation.
10 citations
TL;DR: In this paper, a case-control study of subjects undergoing pleural effusion drainage of pulmonary tuberculosis (case) and chronic heart failure (control) was conducted, where air pollution exposure was measured and PM deposition in the head, tracheobronchial, alveolar region, and total lung region was estimated by Multiple-path Particle Dosimetry (MPPD) Model.
Abstract: Epidemiological studies identified the relationship between air pollution and pulmonary tuberculosis. Effects of lung-deposited dose of particulate matter (PM) on culture-positive pulmonary tuberculosis remain unclear. This study investigates the association between lung-deposited dose of PM and pulmonary tuberculosis pleurisy. A case-control study of subjects undergoing pleural effusion drainage of pulmonary tuberculosis (case) and chronic heart failure (control) was conducted. Metals and biomarkers were quantified in the pleural effusion. The air pollution exposure was measured and PM deposition in the head, tracheobronchial, alveolar region, and total lung region was estimated by Multiple-path Particle Dosimetry (MPPD) Model. We performed multiple logistic regression to examine the associations of these factors with the risk of tuberculosis. We observed that 1-μg/m3 increase in PM10 was associated with 1.226-fold increased crude odds ratio (OR) of tuberculosis (95% confidence interval (CI): 1.023-1.469, p<0.05), 1-μg/m3 increase in PM2.5-10 was associated with 1.482-fold increased crude OR of tuberculosis (95% CI: 1.048-2.097, p < 0.05), 1-ppb increase in NO2 was associated with 1.218-fold increased crude OR of tuberculosis (95% CI: 1.025-1.447, p < 0.05), and 1-ppb increase in O3 was associated with 0.735-fold decreased crude OR of tuberculosis (95% CI: 0.542 0.995). We observed 1-μg/m3 increase in PM deposition in head and nasal region was associated with 1.699-fold increased crude OR of tuberculosis (95% CI: 1.065-2.711, p < 0.05), 1-μg/m3 increase in PM deposition in tracheobronchial region was associated with 1.592-fold increased crude OR of tuberculosis (95% CI: 1.095-2.313, p < 0.05), 1-μg/m3 increase in PM deposition in alveolar region was associated with 3.981-fold increased crude OR of tuberculosis (95% CI: 1.280-12.386, p < 0.05), and 1-μg/m3 increase in PM deposition in total lung was associated with 1.511-fold increased crude OR of tuberculosis (95% CI: 1.050-2.173, p < 0.05). The results indicate that particle deposition in alveolar region could cause higher risk of pulmonary tuberculosis pleurisy than deposition in other lung regions.
1 citations
TL;DR: In this article, the number concentration of PM range from 10nm to 10µm in size, deposition of PM in the respiratory tract, and the inhalation dose for the residents (dormitory, library, canteen, dining-hall, activity center, mosque, gymnasium, hospital, and classroom) were investigated.
Abstract: Indoor environment is the place where people spend most of their time throughout their whole life. Accordingly, the assessment of exposure to particulate matter (PM) in indoor environment is crucial in order to determine the possible health effects. In this study, the number concentration of PM range from 10 nm to 10 µm in size, deposition of PM in the respiratory tract, and the inhalation dose for the residents (dormitory, library, canteen, dining-hall, activity center, mosque, gymnasium, hospital, and classroom) were investigated. An optical particle sizer and a NanoScan scanning mobility particle sizer were used to measure the particle number concentrations in the size range of 10 nm to 300 nm and 300 nm to 10 µm, respectively. The total number concentrations varied from 1.32 × 105 cm−3 to 1.11 × 103 cm−3. Deposition of particles in the respiratory system was predicted by the ICRP model. It was found that 48% of inhaled particles of 20 nm in size was the deposition in the alveolar region whereas 9.6% and 16% were in the head airway and tracheobronchial region, respectively. Maximum inhalation doses were obtained for ultrafine particles in all microenvironments. Finally, the mass deposition in the gymnasium was the highest although the particle concentration was at the last four among other microenvironments. That means physical exertion is a significant factor besides the particle concentration.
TL;DR: In this article , a cross-sectional study was conducted to investigate associations of particulate matter (PM) of less than 2.5 μm in aerodynamic diameter (PM2.5) and PM deposition with nocturnal changes in body composition in obstructive sleep apnea patients.
Abstract: We conducted a cross-sectional study to investigate associations of particulate matter (PM) of less than 2.5 μm in aerodynamic diameter (PM2.5) and PM deposition with nocturnal changes in body composition in obstructive sleep apnea (OSA) patients. A bioelectric impedance analysis was used to measure the pre- and postsleep body composition of 185 OSA patients. Annual exposure to PM2.5 was estimated by the hybrid kriging/land-use regression model. A multiple-path particle dosimetry model was employed to estimate PM deposition in lung regions. We observed that an increase in the interquartile range (IQR) (1 μg/m3) of PM2.5 was associated with a 20.1% increase in right arm fat percentage and a 0.012 kg increase in right arm fat mass in OSA (p < 0.05). We observed that a 1 μg/m3 increase in PM deposition in lung regions (i.e., total lung region, head and nasal region, tracheobronchial region, and alveolar region) was associated with increases in changes of fat percentage and fat mass of the right arm (β coefficient) (p < 0.05). The β coefficients decreased as follows: alveolar region > head and nasal region > tracheobronchial region > total lung region (p < 0.05). Our findings demonstrated that an increase in PM deposition in lung regions, especially in the alveolar region, could be associated with nocturnal changes in the fat percentage and fat mass of the right arm. PM deposition in the alveolar region could accelerate the body fat accumulation in OSA.