Mokoena KK, et al. - A time-series analysis was undertaken to examine a potential link between short-term exposure to ambient air pollutants and respiratory mortality in Xi’an, China. Researchers gathered information regarding daily averages of particulate matter (aerodynamic diameter less than 2.5 μm) PM_2.5, sulfur dioxide (SO₂), ozone, temperature, relative humidity and daily counts of respiratory mortality (2014–2016). They evaluated 7,965 cases of respiratory mortality. Chronic lower respiratory diseases, influenza and pneumonia, as well as other forms of respiratory diseases were reported as the cause of 62.9, 28.5, and 8.6% of mortality, respectively. A significant association of respiratory mortality in Xi’an with exposure to ambient air pollutants from 2014 to 2016 was evident. In the single pollutant model, a significant association of 10 μg/m³ increase in a two-day moving average of PM_2.5, and SO₂ levels, with relative risk 1.313 and 1.4020 of respiratory mortality, respectively, was revealed.