Sandstorm and its effect on particulate matter PM 2.5, carbon monoxide, nitrogen dioxide, ozone pollutants and SARS-CoV-2 cases and deaths.

Sandstorms are a natural metrological phenomenon, frequently occurring in many arid and semi-arid regions of the world. The sandstorm dust contains environmental pollutants, microorganisms including bacteria, fungi, and viruses. These events are the primary sources of air pollution and its long-distance transport. Thus, sandstorms are becoming a greater concern during the COVID-19 pandemic. Therefore, this novel study aimed to investigate the effect of a sandstorm on "environmental pollutants particulate matter (PM2.5), carbon monoxide (CO), ozone (O3), nitrogen dioxide (NO2), and day-to-day new cases and deaths due to Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection" in Riyadh, Saudi Arabia. On March 12, 2021, a sandstorm occurred in the Riyadh region, the capital city of Saudi Arabia. The data on PM 2.5, CO, NO2, and O3 were recorded three weeks before and three weeks after the onset of the sandstorm, from February 20, 2021, to March 12, 2021, and from March 13 to April 2, 2021. The daily PM2.5, CO, NO2, and O3 levels were documented from the metrological websites, and Air Quality Index-AQI, COVID-19 daily cases, and deaths were obtained from Saudi Arabia's official coronavirus website. After sandstorm, the air pollutants, CO level increased by 84.25%; PM2.5: 76.71%; O3: 40.41%; NO2: 12.03%; and SARS-CoV-2 cases increased by 33.87%. However, the number of deaths decreased by 22.39%. The sandstorm event significantly increased the air pollutants, PM2.5, CO, and O3, which were temporally associated with increased SARS-COV-2 cases. However, no significant difference was noticed in NO2 and the number of deaths after the sandstorm. The findings have an important message to health authorities to timely provide information to the public about the sandstorm and its associated health problems, including SARS-CoV-2 cases and deaths.