Environ Epidemiol. 2026 Jun 1;10(3):e491. doi: 10.1097/EE9.0000000000000491. eCollection 2026 Jun.
ABSTRACT
BACKGROUND: Rigorous studies are needed to defend the current National Ambient Air Quality Standards and prompt policymakers to acknowledge a dose-response relationship between air pollution and respiratory outcomes. In the most recent Environmental Protection Agency comprehensive review, scientists determined there was insufficient evidence to claim a causal relationship between chronic particulate matter air pollution (PM2.5) and respiratory outcomes, despite acknowledging one for cardiovascular outcomes (Integrated Science Assessment, Table 5-27).
METHODS: This study examined the associations between chronic PM2.5 levels and respiratory outcomes in 169,713 patients within Kaiser Permanente Northern California who had chronic obstructive pulmonary disease (COPD) between 2007 and 2016.
RESULTS: For every 10 μg/m3 rise in average yearly PM2.5, there was a statistically significant increase in relative risk of death (hazard ratio [HR] = 1.15; 95% confidence interval [CI] = 1.10, 1.20), respiratory-related death (HR = 1.22; 95% CI = 1.15, 1.30), COPD exacerbation (HR = 1.35; 95% CI = 1.29, 1.41), and the combined endpoint of COPD exacerbation or respiratory-related hospitalization with any-cause death as competing risk (HR = 1.30; 95% CI = 1.25, 1.35). We demonstrate a dose-response relationship between 1-year average PM2.5 exposure and respiratory outcomes for key regulatory categories of PM2.5.
CONCLUSIONS: These findings add rigorous evidence to support the continuation of the current annual PM2.5 standard, which was lowered to 9 μg/m3 in 2024. Our novel contribution is documenting the dose-response relationship between chronic PM2.5 and multiple respiratory outcomes in a longitudinal cohort with patients followed for up to 10 years.
PMID:42245542 | PMC:PMC13232900 | DOI:10.1097/EE9.0000000000000491