A comprehensive study conducted by researchers from Wuhan University of Science and Technology has found a significant link between high ozone (O3) exposure and mortality rates. The study, published in Environmental Science and Ecotechnology, examined a nationwide cohort of 20,882 participants over a seven-year period from 2011 to 2018.
The findings reveal that even a modest increase of 10 μg m−3 in O3 concentration was associated with an 18% higher risk of all-cause mortality. Notably, the study focused on warm-season ozone exposure, which remains a pressing concern in China despite the implementation of the Air Pollution Prevention and Control Action Plan in 2013.
The relationship between long-term O3 exposure and mortality risk showed a J-shaped pattern, indicating a non-linear association with a potential O3 concentration threshold. Interestingly, individuals residing in colder climates faced increased mortality risks due to long-term ozone exposure, emphasizing the significance of geographical and climate factors in assessing the health impacts of air pollution.
The study also revealed regional disparities, with China exhibiting higher risk estimates compared to recent findings from Europe and North America. These variations may be attributed to differences in exposure metrics, population susceptibility, and lower ozone concentrations in developed nations.
However, it’s important to acknowledge the study’s limitations. Ozone exposure assessment was based on city-level data rather than individual-level exposure. Indoor ozone exposure and potential confounding factors like traffic noise or other climatic conditions were not considered. Furthermore, the study couldn’t explore associations between ozone exposure and cause-specific mortality due to the lack of clinical diagnoses regarding the cause of death.
These findings shed light on the detrimental health effects of high ozone exposure and underline the need for targeted efforts to mitigate air pollution, considering both local and global factors.