Paulin LM, Gassett AJ, Alexis NE, et al. - This multicenter cross-sectional study was done from November 1, 2010, to July 31, 2018, on 1,874 current and previous smokers with or without COPD to examine the correlation of historical ozone exposure with the hazard of COPD, CT scan measures of respiratory disease, patient-reported results, severity of the disease and aggravations in smokers with or at risk for COPD. The investigators found that for individuals with a history of heavy smoking long-term historical ozone exposure was correlated with decreased lung function, greater emphysema and air trapping on CT scan, worse individual-reported results, and raised respiratory aggravations. Moreover, with an intention to preserve the most vulnerable people of the US population, the relationship between ozone exposure and adverse respiratory results proposes the necessity for a further reassessment of ambient pollution standards.