Department of Electrical, Computer and Biomedical Engineering, University of Pavia, Pavia, Italy.
Department of Civil Engineering and Architecture, University of Pavia, Pavia, Italy.
PLoS One. 2022 Mar 28;17(3):e0263265. doi: 10.1371/journal.pone.0263265. eCollection 2022.
In the last century, the increase in traffic, human activities and industrial production have led to a diffuse presence of air pollution, which causes an increase of risk of several health conditions such as respiratory diseases. In Europe, air pollution is a serious concern that affects several areas, one of the worst ones being northern Italy, and in particular the Po Valley, an area characterized by low air quality due to a combination of high population density, industrial activity, geographical factors and weather conditions. Public health authorities and local administrations are aware of this problem, and periodically intervene with temporary traffic limitations and other regulations, often insufficient to solve the problem. In February 2020, this area was the first in Europe to be severely hit by the SARS-CoV-2 virus causing the COVID-19 disease, to which the Italian government reacted with the establishment of a drastic lockdown. This situation created the condition to study how significant is the impact of car traffic and industrial activity on the pollution in the area, as these factors were strongly reduced during the lockdown. Differently from some areas in the world, a drastic decrease in pollution measured in terms of particulate matter (PM) was not observed in the Po Valley during the lockdown, suggesting that several external factors can play a role in determining the severity of pollution. In this study, we report the case study of the city of Pavia, where data coming from 23 air quality sensors were analyzed to compare the levels measured during the lockdown with the ones coming from the same period in 2019. Our results show that, on a global scale, there was a statistically significant reduction in terms of PM levels taking into account meteorological variables that can influence pollution such as wind, temperature, humidity, rain and solar radiation. Differences can be noticed analyzing daily pollution trends too, as-compared to the study period in 2019-during the study period in 2020 pollution was higher in the morning and lower in the remaining hours.
在上个世纪，交通、人类活动和工业生产的增加导致了空气污染的扩散，这增加了许多健康问题的风险，如呼吸道疾病。在欧洲，空气污染是一个严重的问题，影响了几个地区，其中最严重的地区之一是意大利北部，特别是波河谷地区，由于人口密度高、工业活动、地理因素和天气条件的综合作用，该地区空气质量较差。公共卫生当局和地方政府意识到了这个问题，并定期采取临时交通限制和其他法规措施，但这些措施往往不足以解决问题。2020 年 2 月，该地区是欧洲第一个受到导致 COVID-19 疾病的 SARS-CoV-2 病毒严重影响的地区，意大利政府对此作出反应，实施了严厉的封锁措施。这种情况创造了研究汽车交通和工业活动对该地区污染影响的条件，因为这些因素在封锁期间大大减少了。与世界上一些地区不同，波河谷地区在封锁期间没有观察到颗粒物（PM）污染的显著下降，这表明几个外部因素可能在确定污染的严重程度方面发挥作用。在这项研究中，我们报告了帕维亚市的案例研究，分析了来自 23 个空气质量传感器的数据，以比较封锁期间测量的水平与 2019 年同期的水平。我们的结果表明，就 PM 水平而言，在考虑到可能影响污染的气象变量（如风和温度、湿度、降雨和太阳辐射）时，全球范围内存在统计学上的显著减少。通过分析每日污染趋势也可以注意到差异，与 2019 年的研究期间相比，在 2020 年的研究期间，早晨的污染较高，其余时间的污染较低。
