Air quality and COVID-19 adverse outcomes: Divergent views and experimental findings

Abstract

Background The questioned link between air pollution and coronavirus disease 2019 (COVID-19) spreading or related mortality represents a hot topic that has immediately been regarded in the light of divergent views. A first “school of thought” advocates that what matters are only standard epidemiological variables (i.e. frequency of interactions in proportion of the viral charge). A second school of thought argues that co-factors such as quality of air play an important role too. Methods We analyzed available literature concerning the link between air quality, as measured by different pollutants and a number of COVID-19 outcomes, such as number of positive cases, deaths, and excess mortality rates. We reviewed several studies conducted worldwide and discussing many different methodological approaches aimed at investigating causality associations. Results Our paper reviewed the most recent empirical researches documenting the existence of a huge evidence produced worldwide concerning the role played by air pollution on health in general and on COVID-19 outcomes in particular. These results support both research hypotheses, i.e. long-term exposure effects and short-term consequences (including the hypothesis of particulate matter acting as viral “carrier”) according to the two schools of thought, respectively. Conclusions The link between air pollution and COVID-19 outcomes is strong and robust as resulting from many different research methodologies. Policy implications should be drawn from a “rational” assessment of these findings as “not taking any action” represents an action itself.

Impact of climatic, demographic and disease control factors on the transmission dynamics of COVID-19 in large cities worldwide

“…We find the strongest socioeconomic predictor to be historical exposure to air pollution, likely a proximal indicator for more industrialised and congested population contact patterns. Additionally, other studies have argued air quality to have a more direct role in COVID-19 transmission and disease [ 41 ].…”

Analysis of the New Kuznets Relationship: Considering Emissions of Carbon, Methanol, and Nitrous Oxide Greenhouse Gases—Evidence from EU Countries

“…Even if the nature of air pollution is changing, with household air pollution declining since 1990, mostly due to the substitution of energy fossil fuel sources by renewable sources [ 3 , 25 ], the offsetting of these gains in developed countries like the European countries, is driven by the rapid expansion of megacities, industrial production globalization, pesticide and toxic chemicals proliferation, and to the growing use of motor vehicles [ 2 , 7 ]. These all have harmful effects on the health of individuals due to the extensive pollution they still carry [ 21 , 22 , 24 ].…”

“…Therefore, a broader debate emerges besides the simple legally mandated air quality standards and imposed by EU legislation [21]. This link between the EKC hypothesis regarding economic growth and pollution effects is thus strengthened by the emergence of the consequent health impacts [21][22][23][24][25].…”

“…Recent studies provide in depth literature reviews in the research fields of air pollution and child health [ 21 ], on the impact of nanomaterials on the environment [ 22 ], and the environmental Kuznets curve research [ 23 ]. From these literature review examples, it is clear that countries’ environmental degradation runs in parallel with the economy and that health effects arise from here [ 24 , 25 ]. In [ 24 ] evidence for the relationship between particulate matter (PM) exposure and health effects (specifically, cardiopulmonary morbidity and mortality) is presented.…”

“…Additionally, [ 25 ] questioned the link between air pollution and the coronavirus disease 2019 spread (COVID-19), exploring the literature linking air quality (as measured by different pollutants) to health effects in general, and the new pandemic in particular. It is even argued in the literature that air quality provokes different impacts.…”