Respiratory Tract Deposition of Inhaled Wood Smoke Particles in Healthy Volunteers.
BACKGROUND
Respiratory tract deposition of air pollution particles is a key to their adverse health effects. This study was aimed to determine the size-resolved deposition fraction (DF) of sooty wood smoke particles in the lungs of healthy subjects. The type of wood smoke investigated is typical for household air pollution from solid fuels, which is among the largest environmental health problems globally.


METHODS
Twelve healthy volunteers inhaled diluted wood smoke from incomplete soot-rich combustion in a common wood stove. The DF of smoke particles (10-500 nm) was measured during three 15-min exposures in each subject during spontaneous breathing. Lung function was measured using standard spirometry.


RESULTS
The total DFs by particle number concentration were 0.34±0.08. This can be compared with DFs of 0.21-0.23 in healthy subjects during previous experiments with wood pellet combustion. For particle mass, the total DFs found in this study were 0.22±0.06. DF and breathing frequency were negatively correlated as expected from model calculations (p<0.01).


CONCLUSIONS
The DF of the investigated sooty wood smoke particles was higher than for previously investigated particles generated during more efficient combustion of biomass. Together with toxicological studies, which have indicated that incomplete biomass combustion particles rich in soot and polycyclic aromatic hydrocarbons (PAHs) are especially harmful, these data highlight the health risks of inadequate wood combustion.
1 Department of Public Health and Clinical Medicine, Division of Medicine/Respiratory Medicine, Umeå University , Umeå, Sweden .
Ala
A
Muala
2 Department of Design Sciences, Division of Ergonomics and Aerosol Technology (EAT), Lund University , Lund, Sweden .
Hanna
H
Nicklasson
3 Department of Applied Physics and Electronics, Thermochemical Energy Conversion Laboratory, Umeå University , Umeå, Sweden .
Christoffer
C
Boman
4 Department of Physics, Division of Nuclear Physics, Lund University , Lund, Sweden .
Erik
E
Swietlicki
3 Department of Applied Physics and Electronics, Thermochemical Energy Conversion Laboratory, Umeå University , Umeå, Sweden .
Robin
R
Nyström
3 Department of Applied Physics and Electronics, Thermochemical Energy Conversion Laboratory, Umeå University , Umeå, Sweden .
Esbjörn
E
Pettersson
1 Department of Public Health and Clinical Medicine, Division of Medicine/Respiratory Medicine, Umeå University , Umeå, Sweden .
Jenny A
JA
Bosson
2 Department of Design Sciences, Division of Ergonomics and Aerosol Technology (EAT), Lund University , Lund, Sweden .
Jenny
J
Rissler
1 Department of Public Health and Clinical Medicine, Division of Medicine/Respiratory Medicine, Umeå University , Umeå, Sweden .
Anders
A
Blomberg
1 Department of Public Health and Clinical Medicine, Division of Medicine/Respiratory Medicine, Umeå University , Umeå, Sweden .
Thomas
T
Sandström
2 Department of Design Sciences, Division of Ergonomics and Aerosol Technology (EAT), Lund University , Lund, Sweden .
Jakob
J
Löndahl
D000328:Adult; D000336:Aerosols; D003296:Cooking / Q000295:instrumentation*; D004867:Equipment Design; D005260:Female; D005390:Fires; D064368:Healthy Volunteers; D006361:Heating / Q000295:instrumentation*; D006801:Humans; D019570:Inhalation Exposure / Q000009:adverse effects*; D008168:Lung / Q000378:metabolism*; D008297:Male; D008954:Models, Biological; D010316:Particle Size; D012119:Respiration; D018570:Risk Assessment; D012906:Smoke / Q000009:adverse effects*; D053260:Soot / Q000009:adverse effects; D014934:Wood; D055815:Young Adult
D000336:Aerosols; D012906:Smoke; D053260:Soot
aerosol; biomass combustion; effective density; lung deposition; nanoparticles; toxicity