Exposure to ambient air pollution presents great adverse health risks to respiratory health, and assessing the respiratory exposure doses, especially in the human deep lung regions, remains difficult due to the sheer complexity of the process. To bridge this gap, an extended large-to-small conducting lung airway model was adopted in this study, which includes a broad scope containing bronchial airways up to the 15th generation. Accumulation mode particles in the size range of 100 nm to 3.0 μm representing major size spectrum of coarse diesel exhaust were released at the inlet of respiratory airway model, and both airflow and particle deposition characteristics were numerically investigated. The simulation results showed that the particle deposition in the respiratory airway is sensitive to the variation of inhalation flow rates. For inhalation exposure at lower breathing rate of 18 L/min, both deposited diffusive and inertia particles were very unevenly distributed in the lower respiratory airway. For inhalation exposure at higher breathing rate of 50 L/min, deposited diffusive and inertia particles were both scattered over the lower respiratory airway. In addition, high inhalation flow rate enabled inertia particles to be deposited further d ownstream of the airway with deposition hot spots observed in distal airways.
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Corley, R. A., Kabilan, S., Kuprat, A. P., Carson, J. P., Minard, K. R., Jacob, R. E., Timchalk, C., Glenny, R., Pipavath, S., Cox, T., Wallis, C. D., Larson, R. F., Fanucchi, M. V., Postlethwait, E. M., Einstein, D. R. 2012. Comparative computational modeling of airflows and vapor dosimetry in the respiratory tracts of rat, monkey, and human. Toxicol Sci, 128: 500–516.
Dong, J., Inthavong, K., Tu, J. 2017. Multiphase flows in biomedical applications. In: Handbook of Multiphase Flow Science and Technology. Yeoh, G. H. Ed. Singapore: Springer Singapore.
Ema, M., Naya, M., Horimoto, M., Kato, H. 2013. Developmental toxicity of diesel exhaust: A review of studies in experimental animals. Reprod Toxicol, 42: 1–17.
Ge, Q. J., Inthavong, K., Tu, J. Y. 2012. Local deposition fractions of ultrafine particles in a human nasal-sinus cavity CFD model. Inhal Toxicol, 24: 492–505.
Holmér, I., Kuklane, K., Gao, C. 2007. Minute volumes and inspiratory flow rates during exhaustive treadmill walking using respirators. Ann Occup Hyg, 51: 327–335.
Horsfield, K., Dart, G., Olson, D. E., Filley, G. F., Cumming, G. 1971. Models of the human bronchial tree. J Appl Physiol, 31: 207–217.
Inthavong, K., Tian, L., Tu, J. 2016. Lagrangian particle modelling of spherical nanoparticle dispersion and deposition in confined flows. J Aerosol Sci, 96: 56–68.
Inthavong, K., Tu, J., Ahmadi, G. 2009. Computational modelling of gas-particle flows with different particle morphology in the human nasal cavity. J Comput Multiphase Flows, 1: 57–82.
Islam, M. S., Saha, S. C., Sauret, E., Gemci, T., Gu, Y. T. 2017. Pulmonary aerosol transport and deposition analysis in upper 17 generations of the human respiratory tract. J Aerosol Sci, 108: 29–43.
Kolanjiyil, A. V., Kleinstreuer, C. 2017. Computational analysis of aerosol-dynamics in a human whole-lung airway model. J Aerosol Sci, 114: 301–316.
Li, A., Ahmadi, G. 1992. Dispersion and deposition of spherical particles from point sources in a turbulent channel flow. Aerosol Sci Tech, 16: 209–226.
Longest, P. W., Oldham, M. J. 2008. Numerical and experimental deposition of fine respiratory aerosols: Development of a twophase drift flux model with near-wall velocity corrections. J Aerosol Sci, 39: 48–70.
Longest, P. W., Vinchurkar, S., Martonen, T. 2006. Transport and deposition of respiratory aerosols in models of childhood asthma. J Aerosol Sci, 37: 1234–1257.
Longest, P. W., Xi, J. 2007. Effectiveness of direct Lagrangian tracking models for simulating nanoparticle deposition in the upper airways. Aerosol Sci Tech, 41: 380–397.
Ounis, H., Ahmadi, G., Mclaughlin, J. B. 1991. Brownian diffusion of submicrometer particles in the viscous sublayer. J Colloid Interf Sci, 143: 266–277.
Peters, S., Carey, R. N., Driscoll, T. R., Glass, D. C., Benke, G., Reid, A., Fritschi, L. 2015. The Australian work exposures study: Prevalence of occupational exposure to diesel engine exhaust. Ann Occup Hyg, 59: 600–608.
Pichelstorfer, L., Winkler-Heil, R., Hofmann, W. 2013. Lagrangian/Eulerian model of coagulation and deposition of inhaled particles in the human lung. J Aerosol Sci, 64: 125–142.
Riedl, M. A., Diaz-Sanchez, D., Linn, W. S., Gong, H., Jr., Clark, K. W., Effros, R. M., Miller, J. W., Cocker, D. R., Berhane, K. T. 2012. Allergic inflammation in the human lower respiratory tract affected by exposure to diesel exhaust. Res Rep Health Eff Inst, 165: 5–43; discussion 45–64.
Rissler, J., Swietlicki, E., Bengtsson, A., Boman, C., Pagels, J., Sandström, T., Blomberg, A., Löndahl, J. 2012. Experimental determination of deposition of diesel exhaust particles in the human respiratory tract. J Aerosol Sci, 48: 18–33.
Shang, Y., Dong, J., Tian, L., Inthavong, K., Tu, J. 2019. Detailed computational analysis of flow dynamics in an extended respiratory airway model. Clin Biomech, 61: 105–111.
Spiegel, M., Redel, T., Zhang, Y. J., Struffert, T., Hornegger, J., Grossman, R. G., Doerfler, A., Karmonik, C. 2011. Tetrahedral vs. polyhedral mesh size evaluation on flow velocity and wall shear stress for cerebral hemodynamic simulation. Comput Methods Biomech Biomed Eng, 14: 9–22.
Sul, B., Oppito, Z., Jayasekera, S., Vanger, B., Zeller, A., Morris, M., Ruppert, K., Altes, T., Rakesh, V., Day, S., Robinson, R., Reifman, J., Wallqvist, A. 2018. Assessing airflow sensitivity to healthy and diseased lung conditions in a computational fluid dynamics model validated in vitro. J Biomech Eng 140: 051009.
Tu, J., Inthavong, K., Ahmadi, G. 2012. The human respiratory system. In: Computational Fluid and Particle Dynamics in the Human Respiratory System. Tu, J., Inthavong, K., Ahmadi, G. Eds. Dordrecht: Springer Netherlands.
Tu, J., Inthavong, K., Wong, K. K. L. 2015. Geometric model reconstruction. In: Computational Hemodynamics—Theory, Modelling And Applications. Dordrecht: Springer Netherlands.
Wade, J. F. 3rd., Newman, L. S. 1993. Diesel asthma. Reactive airways disease following overexposure to locomotive exhaust. J Occup Med, 35: 149–154.
Weibel, E. R. 1963. Principles and methods for morphometric study of lung and other organs. Lab Invest, 12: 131–155.
Yu, G., Zhang, Z., Lessmann, R. 1996. Computer simulation of the flow field and particle deposition by diffusion in a 3-D human airway bifurcation. Aerosol Sci Tech, 25: 338–352.
Zhang, Z., Kleinstreuer, C. 2011. Computational analysis of airflow and nanoparticle deposition in a combined nasal–oral–tracheobronchial airway model. J Aerosol Sci, 42: 174–194.
Zhang, Z., Kleinstreuer, C., Donohue, J. F., Kim, C. S. 2005. Comparison of micro- and nano-size particle depositions in a human upper airway model. J Aerosol Sci, 36: 211–233.
Zhang, Z., Kleinstreuer, C., Kim, C. S. 2009. Comparison of analytical and CFD models with regard to micron particle deposition in a human 16-generation tracheobronchial airway model. J Aerosol Sci, 40: 16–28.
This study was funded by the National Natural Science Foundation of China (Grant Nos. 91643102 and 81700094) and Australian Research Council (Project ID: DP160101953 and DE180101138).
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Dong, J., Tian, L. & Ahmadi, G. Numerical assessment of respiratory airway exposure risks to diesel exhaust particles. Exp. Comput. Multiph. Flow 1, 51–59 (2019). https://doi.org/10.1007/s42757-019-0005-2
- diesel exhaust
- respiratory airway
- occupational hygiene
- accumulation mode particles
- lobar deposition