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Updated: Sep 24, 2025
08:17
Generation of a Chronic Obstructive Pulmonary Disease Model in Mice by Repeated Ozone Exposure
Published on: August 25, 2017
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Cohort-based long-term ozone exposure-associated mortality risks with adjusted metrics: A systematic review and
Haitong Zhe Sun1,2, Pei Yu3, Changxin Lan4,5
1Centre for Atmospheric Science, Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, UK.
Innovation (Cambridge (Mass.))
|May 6, 2022
Summary
Long-term ozone (O3) exposure increases mortality risk, particularly from respiratory and cardiovascular causes. This study unified exposure metrics to provide more accurate meta-estimations of O3
Area of Science:
- Environmental Health Sciences
- Epidemiology
- Toxicology
Background:
- Long-term exposure to ambient ozone (O3) is linked to non-communicable diseases and increased mortality.
- Existing cohort studies on O3 exposure and mortality are limited, with inconsistent exposure metrics hindering meta-analysis.
- Standardizing O3 exposure metrics is crucial for credible epidemiological evidence synthesis.
Purpose of the Study:
- To update systematic reviews on O3 exposure and cause-specific mortality risks.
- To provide more accurate meta-estimations by unifying inconsistent exposure metrics.
- To quantify the association between O3 exposure and mortality using standardized metrics.
Main Methods:
- Systematic review and meta-analysis of 25 studies (14 unique cohorts, >226 million participants).
- Estimation of cross-metric conversion factors for O3 exposure metrics (1990-2019).
- Application of the Hunter-Schmidt random-effects model to pool relative risks.
Main Results:
- A 10 nmol mol⁻¹ (ppbV) increase in O3 exposure was associated with increased all-cause mortality (RR: 1.014, 95% CI: 1.009-1.019).
- Significant associations were found for respiratory (RR: 1.025), COPD (RR: 1.056), cardiovascular (RR: 1.019), and congestive heart failure mortality (RR: 1.074).
- Insignificant associations were observed for ischemic heart disease, cerebrovascular diseases, and lung cancer mortality.
Conclusions:
- Unified exposure metrics strengthen the foundation for multi-study meta-analyses of O3's health effects.
- Long-term O3 exposure poses considerable cardiopulmonary hazards and increases all-cause mortality risk.
- Further research with diverse populations and improved O3 monitoring is needed to fully understand O3-associated health effects.
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