Experimentally determined deposition of ambient urban ultrafine particles in the respiratory tract of children

Lingli Guo, Fahard Salimi, Hao Wang, Werner Hofmann, Graham R. Johnson, Brett G. Toelle, Guy B. Marks, Lidia Morawska*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

4 Citations (Scopus)
18 Downloads (Pure)


A critical element of the risk assessment of exposure to airborne ambient ultrafine particles (UFP) is the quantification of respiratory tract deposition (RTD) of the particles, which is intrinsically challenging, particularly at the population scale. In this study, we used a recently proposed method to experimentally determine the RTD of urban UFP in a large group of children exposed to these particles in a school setting in Brisbane, Australia. Children are one of the most susceptible population groups; However, little is known about the deposition of UFP from urban traffic in their airways. In order to advance the knowledge in this field, the objectives of this study were: to determine the deposition of ambient urbane UFP in large number children, to catergorize the source of inhaled UFPs and hence to assess the contribution of air pollution sources to the deposition.

RTD was measured in children aged 8-11 at primary schools using a flow-through chamber bag system. First, the inhaled and exhaled air was separated; then the particle number size distribution and particle number concentration were measured. The sources of inhaled UFP were categorized according to their particle number size distribution by a K means cluster technique.

A total of 128 children from five schools performed the RTD measurement. The mean total deposition fraction of urban UFP in all children was 0.59 ± 0.10. Inhaled UFP were categorized into two groups: traffic and urban background, with the GMD of corresponding particle number size distribution of 20 nm and 40 nm, respectively. The total deposition fraction (mean ± SD) of UFP from these two groups was 0.68 ± 0.09 for traffic and 0.55 ± 0.08 for urban background respectively.

This is the first study in which RTD was measured in a large group of children inhaling real urban UFP. First, we proved that this novel method can indeed be applied easily and quickly to a large group of people. Second, we quantified the RTD of children, thus providing an important input to the risk assessment for exposure to UFP.

Original languageEnglish
Article number106094
Pages (from-to)1-8
Number of pages8
JournalEnvironment International
Publication statusPublished - Dec 2020
Externally publishedYes

Bibliographical note

Copyright the Author(s) 2020. Version archived for private and non-commercial use with the permission of the author/s and according to publisher conditions. For further rights please contact the publisher.


  • Ultrafine particles
  • Respiratory tract deposition
  • Urban exposure
  • Dose
  • Children
  • Primary school


Dive into the research topics of 'Experimentally determined deposition of ambient urban ultrafine particles in the respiratory tract of children'. Together they form a unique fingerprint.

Cite this