Seasonal variation of AhR-mediated effects of organic
air pollutants from a year-long sampling campaign
Anita Érseková1, Jiří Novák1, John Paul Giesy2 and Jana Klánová1
1Research Centre for Toxic Compounds in the Environment, Masaryk University,
Kamenice 3, 625 00 Brno, Czech Republic
2Dept. Biomed. Veterin. Sciences and Toxicol. Centre, University of
Saskatchewan
Corresponding author: ersekova@recetox.muni.cz
Objectives
Introduction
Our work describes specific biological effects of air
samples from a year long sampling campaign
obtained by active air sampler at two localities to
address the influence of city agglomeration as an
air pollution source on the surrounding area.
Our work also examines whether AhR-mediated
activity has a seasonal variation during year.
•
•
environmental air samples contain complex mixtures of pollutants that could produce toxic effects
clinical studies indicate that primarily affected systems are the cardiovascular and the respiratory
system (1)
• toxic effects of the pollutant mixtures can be assessed only by bioassays, chemical analyses are not
sufficient
• AhR-mediated effect is a frequently used marker of biological contamination (2); this type of effect is
associated with immunity, carcinogenicity and endocrine disruption (2, 3)
Conclusion
Results and discussion
• our results demonstrate utility of in vitro biotests
in assessment of specific biological effects of
environmental air samples
• we have demonstrated seasonal variability of
AhR-mediated activity in gaseous and in
particulate phase
• based on AhR-mediated toxicity data Brno city
air pollution have not significant influence on
village ambient air; the high air pollution levels
in the village were caused probably by local
sources such as heating at least during cold
seasons
 the greatest effects were observed with winter samples from both localities
 summer samples produced the mostly the lowest effects probably due fotodegradation and lower
activity of local heating
 interestingly, data from village site show three times greater bioTEQ levels in winter (particulate
phase) and autumn samples (gaseous phase) than in the samples from City site; this is probably
caused by coal and waste burning at the village during cold seasons that does not occur in the city
so much
 data from gaseous phase generally show lower dioxin-like activity than particulate matter samples
(Fig. 1, 2).
 seasonal variation was distinctive in both phases (Fig. 1, 2), interestingly autumn gaseous phase
samples show higher level of AhR-activity that winter samples, it could be caused by low air
temperatures that decrease gas/particle partitioning ratio in favor of particulates
bioTEQ [fg/m3]
H4IIE-luc, rat hepato-carcinoma cells stably transfected
with the luciferase gene under control of AhR were used
for analysis of dioxin-like activity of the air samples.
Results of the bioassays were reported as bioTEQ
expressed as [fg] of TCDD per m3 based on EC50 values
from calibration curve of the respective model compound.
1000
100
Air samples were collected for one year at a trafficburdened City site in Brno (Czech Republic) and a village
site about 8 km from Brno city to address the influence of
city agglomeration as an air pollution source on the
surrounding area.
Village (Telnice)
10
1
Studied air samples
City (Brno)
n.a.
Spring Summer Autumn Winter
Fig. 1: AhR-mediated effects of the gaseous phase air
samples; bioTEQ50 - biotest assessed toxic
equivalent of TCDD calculated from EC50 of TCDD;
n.a.- effect did not reach EC50
10000
bioTEQ [fg/m3]
Material and methods
Gaseous phase
1000
Particulate phase
City (Brno)
Village (Telnice)
100
10
Spring Summer Autumn Winter
Fig. 2: AhR-mediated effects of the particulate phase
air samples; bioTEQ50 - biotest assessed toxic
equivalent of TCDD calculated from EC50 of TCDD
References
Acknowledgements
This research was supported by GACR P503/10/P249
and CETOCOEN (CZ.1.05/2.1.00/01.0001).
1 Kampa, M., Castanas, E. 2007. Human health effects of air pollution. Environ. Pollut. 151(2): pp. 362–367.
2 Novák, J., Jálová, V., Giesy, J. P. and Hilscherová, K. 2009. Pollutants in particulate and gaseous fractions of ambient air
interfere with multiple signaling pathways in vitro. Environ. Int. 35(1): pp. 43-49.
3 Safe, S., Wormke, M. 2003. Inhibitory aryl hydrocarbon receptor-estrogen receptor alpha cross-talk and mechanisms of
action. Chem. Res. Toxicol. 16 : pp. 807–816.