EUKN - European Urban Knowledge Network - Decline of ambient air pollution levels and improved respiratory health in Swiss children

Decline of ambient air pollution levels and improved respiratory health in Swiss children

Introduction

The causality of observed associations between air pollution and respiratory health in children is still subject to debate. If reduced air pollution exposure resulted in improved respiratory health of children, this would argue in favour of a causal relation.

Description

This research shows whether a rather moderate decline of air pollution levels in the 1990s in Switzerland was associated with a reduction in respiratory symptoms and diseases in school children. In nine Swiss communities, 9,591 children participated in cross-sectional health assessments between 1992 and 2001. Findings show that the reduction of air pollution exposures contributes to improved respiratory health in children. Current air pollution levels in Switzerland still exceed limit values of the Swiss Clean Air Act; thus, children’s health can be improved further.

Methodology

In nine Swiss communities, 9,591 children participated in cross-sectional health assessments between 1992 and 2001. Their parents completed identical questionnaires on health status and covariates. Each child was assigned an estimate of regional particles with an aerodynamic diameter < 10 μg/m3 (PM10) and determined change in PM10 since the first survey. To analyze the association between change of air pollution levels and change of respiratory health, multi-variate logistic regression models were used.

All this was meant to see whether a causality could be observed between air pollution and respiratory health in children.

Conclusions

The air pollution abatement measures implemented in Switzerland in the 1990s that resulted in moderately reduced air pollution exposures, have successfully contributed to improved respiratory health in Swiss schoolchildren;
thus, not only dramatic changes, but also modest improvements of ambient air pollution seem to be beneficial for children’s respiratory health;
the larger reduction in symptom rates in areas with a stronger decrease in PM10 levels supports the causality of observed associations between air pollution and respiratory health in children (PM10: an estimate of regional particles with an aerodynamic diameter < 10 μg/m3);
the findings do not suggest a threshold for adverse effects of PM10, because beneficial effects of rather small PM10 reductions in a moderately polluted environment were observed;
in urban regions and in the proximity of streets with high traffic volume, current PM10 levels still exceed limit values of the Swiss Clean Air Act. Therefore, it can be assumed that there is still a potential for further improvement of both ambient air pollution and children’s health in Switzerland.

Contact info

Institute of Social and Preventive Medicine, University of Basel, Switzerland
Lucy Bayer-Oglesby, tel. +41 61 2676066

Publication date

01/11/2005

Cities

The Swiss areas of:

Lugano, Zürich, Bern and Geneva (urban);
Anières and Biel (suburban);
Langnau and Payerne (rural);
Montana (alpine).

Links

University of Basel

Decline of ambient air pollution levels and improved respiratory health in Swiss children (PDF, Eng, 135 KB)

Document type

research

Themes

Urban Policy > Social inclusion & integration > Quality of life

Keywords

Health