Atmospheric Pollution Laboratory (LCA), Department of Applied Physics, Miguel Hernández University, Avenida de la Universidad S/N, 03202, Elche, Spain.
Atmospheric Pollution Laboratory (LCA), Department of Applied Physics, Miguel Hernández University, Avenida de la Universidad S/N, 03202, Elche, Spain.
Environ Res. 2022 Jan;203:111788. doi: 10.1016/j.envres.2021.111788. Epub 2021 Jul 31.
This work investigates the impact of COVID-19 restrictive measures on the mass concentrations of PM and PM, and their chemical components (water-soluble ions, organic and elemental carbon, and major and trace metals) at an urban site in the western Mediterranean. The evolution of gaseous pollutants (NO, O and some volatile organic compounds) was also analyzed. The concentrations measured during the lockdown in 2020 were compared to those obtained during the same period over the preceding five years. The average decrease in the levels of NO and traffic-related volatile organic compounds was higher than 50 %, while O concentrations did not exhibit significant variations during the study period. Our results show that temporal variations in PM and PM concentrations were strongly affected by the frequency of Saharan dust events. When these episodes were excluded from the analysis period, a 35 % decrease in PM and PM levels was observed. Traffic restrictions during the lockdown led to important reductions in the concentrations of elemental carbon and metals derived from road dust (e.g. Ca and Fe) and break wear (e.g. Cu). Regarding secondary inorganic aerosols, nitrate showed the largest reductions as a consequence of the drop in local emissions of NO.
本研究调查了 COVID-19 限制措施对 PM 和 PM 质量浓度及其化学组分（水溶性离子、有机碳和元素碳以及主要和痕量金属）在西地中海一个城市站点的影响。还分析了气态污染物（NO、O 和一些挥发性有机化合物）的演化。将 2020 年封锁期间测量的浓度与前五年同期获得的浓度进行了比较。NO 和与交通有关的挥发性有机化合物的浓度平均下降了 50%以上，而 O 浓度在研究期间没有显著变化。研究结果表明，PM 和 PM 浓度的时间变化受撒哈拉尘埃事件的频率强烈影响。当将这些事件从分析期排除时，PM 和 PM 水平下降了 35%。封锁期间的交通限制导致源自道路尘埃（如 Ca 和 Fe）和刹车片磨损（如 Cu）的元素碳和金属浓度显著降低。关于二次无机气溶胶，硝酸盐的降幅最大，这是由于当地 NO 排放减少所致。
