Physiological effects on humans when exposed to nanometer sized airborne
particles in well controlled chamber studies
Mats Bohgard1*, Jörn Nielsen2, Inger Hagerman3, Katrin Dierschke2, Christina Isaxon1, Ulla
B.K. Andersson2, Eva Assarsson2, Margareta Berglund3, Anders Gudmundsson1, Bo A.
Jönsson2, Joakim Pagels1, Aneta Wierzbicka1
1
Ergonomics and Aerosol Technology, Lund University, Sweden
Occupational and Environmental Medicine, Lund University, Sweden
3
Department of Cardiology, Karolinska University Hospital, Huddinge, Sweden
2
*
Corresponding email: Mats.Bohgard@design.lth.se
Keywords: nano particles, aerosols, physiological effects, heart rate variability
1 Introduction
There is an increasing concern about airborne
nano sized particles (ultra fine particles) in
indoor environments. Epidemiological studies
show relations between exposure to airborne
particles and morbidity/mortality in respiratory
and cardiovascular diseases (Brook et al., 2004;
Brown et al., 2000; Donaldson et al., 1998;
Ibfelt et al., 2010) There is a need for
experimental studies to get a better
understanding of which particle characteristics
are important for health effects and of the
mechanisms behind these effects.
The objective of this study was to develop a
method for human exposure studies and apply
the method to studies on how nanometer sized
particles affect physiological parameters. We
have performed studies on human exposure to
nanometer sized particles. Prior to the exposure
study, particles from burning candles, welding
and particles produced by terpene ozone
reactions were characterized (Pagels et al. 2008;
Isaxon et al., 2009; Wierzbicka et al. 2008).
2 Materials/Methods
Test subjects (3 at the time) were exposed in a
20 m3 chamber. In a series of experiments, 22
healthy females were exposed to candle smoke,
terpene-ozone generated particles and clean air
according to a double blind protocol.
In another series of experiments 32 males (21
welders and 11 reference persons) were exposed
to welding fume and clean air. Mean
concentrations were 907 000 particles/cm3 (200
μg/m3) for candle smoke, 30 000 particles/cm3
(70 μg/m3) for ozone-terpene generated
particles and 67 000 particles/cm3 (1000
μg/m3) for welding fume. Exposure times were 3
hours for candle and ozone-terpene particles and
6 hours for welding smoke.
Prior to the provocations, test subjects undergo a
physical examination including heart and lung
status and atopy prick-test. Medical and work
history is registered. Before and after exposure,
samples of venous blood, urine, breath
condensate and nasal lavage are taken for
analysis of biochemical markers (oxidative
stress and inflammation). The lung function and
nasal patency are measured by spirometry and
acoustic rhinometry. A venous blood sample
is obtained before, after, and 24 hours after
the provocation for analysis of biochemical
markers of inflammation and oxidative
stress. Symptoms from airways are
registered according to a symptom score
model.
Heart Rate Variability (HRV) was registered
in periods of ten minutes before and during
the provocation (HRV, 1996). Changes in
HRV have shown to be related to risk of
cardiovascular disease.
3 Results
Changes in perceived symptoms were reported
depending on the different exposures. However
significant relations between exposure and
symptoms and results from rhinometry and
spirometry could not be observed. The
biochemical markers analysed so far, do not
show any significant differences for healthy
subjects between exposure to clean air and the
high concentrations of nano–sized particles.
Heart rate was unchanged in all groups during
all exposures. There were no impacts on HRV
of repeated visits in the chamber.
However, exposure to nano sized particles of
burning candles and welding influenced HRV.
Significant changes for some, but not all,
spectral bands were observed. Exposure to
ozone-terpene particles had no significant effect
neither on HRV, nor on inflammatory markers
analysed so far.
4 Conclusions
The developed methodology enables
quantitative determination of physiological
responses in terms of effects on HRV which
can be related to exposures. The method may
be used to get early risk warnings on
physiological effects.
This study was financed by The Swedish Research
Council FORMAS and performed within the
framework of Metalund, the Centre for Medicine and
Technology for Working Life and Society, a
competence centre at Lund University, Sweden,
supported by FAS, the Swedish Council for Working
Life and Social Research.
5 References
Brook R.D., Franklin B., Cascio W., Hong Y.L.,
Howard G., Lipsett M., Luepker R.,
Mittleman M., Samet J., Smith S.C. &
Tager I. 2004. Air pollution and
cardiovascular disease - A statement for
healthcare professionals from the expert
panel on population and prevention science
of the American Heart Association.
Circulation 109, 2655-2671.
Brown D.M., Stone V., Findlay P., MacNee W.
& Donaldson K. 2000 Increased
inflammation and intracellular calcium
caused by ultrafine carbon black is
independent of transition metals or other
soluble components. Occupational and
Environmental Medicine 57, 685-691.
Donaldson K., Li X.Y. & MacNee W. 1998.
Ultrafine (nanometre) particle mediated
lung injury. Journal of Aerosol Science 29,
553-56.
Heart Rate Variability. Standards of
Measurement, Physiological Interpretation
and Clinical Use. Task Force of the
European Society of Cardiology and the
North American Society of Pacing and
Electrophysiology.
1996.
Circulation
93:1043-1065.
Ibfelt, E., Bonde, J.P., Hansen, J. 2010.
Exposure to metal welding fume particles
and risk for cardiovascular disease in
Denmark: a prospective cohort study.
Occup Environ Med 67,772-777
Isaxon, C. ; Pagels, J. Gudmundsson, A.
Asbach, C. and Bohgard, M. 2009.
Characteristics of Welding Fume Aerosol
Investigated in Three Swedish Workshops,
Proc. of 10th International Symposium on
Inhaled Particles, Sheffield, England.
Pagels J., Wierzbicka A., Nilsson E., Isaxon C.,
Dahl A., Gudmundsson A., Swietlicki E.,
Bohgard M., 2008. Chemical Composition
and Mass Emission Factors of different
Particle types present in Candle Smoke,
Journal of Aerosol Science, 40,193-208..
Wierzbicka A., 2008. What are the
characteristics of airborne particles that we
are exposed to? – Focus on Indoor
Environments and Emissions from Biomass
Fires District Heating, Doctoral thesis
Lund University, Sweden.