Size Distribution of Exhaled Particles in the Range from 0.01 to 2.0 µm
Artikel i vetenskaplig tidskrift, 2010

This study investigates the number size distribution of endogenously produced exhaled particles during tidal breathing and breathing with airway closure. This is the first time that the region below 0.4 µm has been investigated. The particle concentration was generally lower for tidal breathing than for airway closure, although the inter-individual variation was large. During tidal breathing, the size distribution peaks at around 0.07 µm. This peak is still present during the airway closure manoeuvre, but an additional broad and strong peak is found between 0.2 and 0.5 µm. This suggests that different mechanisms govern the generation of particles in the two cases. The particles produced from airway closure may be attributed to formation of film droplets in the distal bronchioles during inhalation. It is speculated that the very small particles are film droplets originating from the alveolar region.

exhaled particles

size distribution

tidal breathing

airway closure


Helene Holmgren

Chalmers, Kemi- och bioteknik, Oorganisk miljökemi

Evert Ljungström

Göteborgs universitet

Ann-Charlotte Almstrand

Göteborgs universitet

Björn Bake

Göteborgs universitet

Anna-Carin Olin

Göteborgs universitet

Journal of Aerosol Science

0021-8502 (ISSN)

Vol. 41 5 439-446


Medicinsk laboratorie- och mätteknik

Annan fysik

Folkhälsovetenskap, global hälsa, socialmedicin och epidemiologi



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