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Published in: BMC Public Health 1/2013

Open Access 01-12-2013 | Research article

Meta-analysis of adverse health effects due to air pollution in Chinese populations

Authors: Hak-Kan Lai, Hilda Tsang, Chit-Ming Wong

Published in: BMC Public Health | Issue 1/2013

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Abstract

Background

Pooled estimates of air pollution health effects are important drivers of environmental risk communications and political willingness. In China, there is a lack of review studies to provide such estimates for health impact assessments.

Methods

We systematically searched the MEDLINE database using keywords of 80 major Chinese cities in Mainland China, Hong Kong and Taiwan on 30 June 2012, yielding 350 abstracts with 48 non-duplicated reports either in English or Chinese after screening. We pooled the relative risks (RR) per 10 μg/m3 of particulate matter (PM10), nitrogen dioxide (NO2), sulphur dioxide (SO2) and ozone (O3).

Results

For short-term effects, the pooled RR (p < 0.05) ranges were: 1.0031 (PM10) to 1.0140 (NO2) for all-cause mortality, 1.0034 (cardiopulmonary, PM10) to 1.0235 (influenza and pneumonia, SO2) for 9 specific-causes mortality, 1.0021 (cardiovascular, PM10) to 1.0162 (asthma, O3) for 5 specific-causes hospital admissions. For birth outcomes, the RR (p < 0.05) ranged from 1.0051 (stillbirth, O3) to 1.1189 (preterm-birth, SO2) and for long-term effect on mortality from 1.0150 (respiratory, SO2) to 1.0297 (respiratory, NO2). Publication bias was absent (Egger test: p = 0.326 to 0.624). Annual PM10 and NO2 concentrations were inversely associated with RR of mortality (p = 0.017-0.028).

Conclusions

Evidence on short-term effects of air pollution is consistent and sufficient for health impact assessment but that on long-term effects is still insufficient.
Appendix
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Metadata
Title
Meta-analysis of adverse health effects due to air pollution in Chinese populations
Authors
Hak-Kan Lai
Hilda Tsang
Chit-Ming Wong
Publication date
01-12-2013
Publisher
BioMed Central
Published in
BMC Public Health / Issue 1/2013
Electronic ISSN: 1471-2458
DOI
https://doi.org/10.1186/1471-2458-13-360

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