COVID-19, Ambient Air Pollution, and Environmental Health Inequities in Latin American Cities

Abstract

SARS-CoV-2 infections continue to grow in Latin America, where 80% of the population lives in urban areas that are also home to some of the largest societal inequities in the world. Some national governments across the region have enacted stay-at-home orders, closing schools, and shutting down much of the economy.High levels of air pollution in many Latin American cities in the past may have primed many residents for more severe infection and mortality from COVID-19 by contributing to the development of chronic diseases. Many of the chronic diseases associated with long-term, cumulative exposure to air pollution appear to be correlated with a higher vulnerability to severe COVID-19 outcomes, including hospitalization, need for critical care, and death [1,2]. A recent study in the USA reported that a long-term increase of only 1 μg/m 3 PM 2.5 was associated with an 8% increase in COVID-19 death rate [3]. In addition to cumulative exposures, it is plausible that short-term air pollution exposures interact with SARS-CoV-2 infection itself [4], possibly via their effects on inflammation-related processes. However, the effect of immediate changes in air pollution on COVID-19-related mortality is yet to be tested.Even as air pollution may impact COVID-19 outcomes, stay-at-home orders related to COVID-19 have impacted ambient air pollution levels in some Latin American cities [5][6][7]. We aimed to characterize COVID-19-related reductions in ambient PM 2.5 in four major cities in Latin America and to estimate the magnitude of reductions in adult mortality if long-term exposure to PM 2.5 was lower proportional to levels observed during the COVID-19 shutdowns. We compared ambient fine particulate matter (PM 2.5 ) concentrations during the first week of COVID-19-related school closures in each city with average concentrations for the same period in 2017-2019, using direct measurements from publicly available government air monitor networks in four major Latin American cities. We averaged hourly data from each monitor into a monitor-specific daily mean and considered monitor-days with < 16 valid hourly means to be missing. Daily means from all monitors within the urban core area were averaged into a citywide daily mean. For each of these four cities, we projected the reduction in all-cause mortality among adults aged ≥ 30 years if annual ambient PM 2.5 concentrations were lower proportional to current COVID-19-

NO2 pollution decrease in big cities of Latin America during COVID-19 pandemic

“…During COVID-19 lockdown, many studies [20,21,22,23,24,25,26,27] described the improvement of air quality in big cities around the world associated with decreasement of air pollutant emissions during COVID-19 measures implementations. Particularly, nitrogen dioxide (NO 2 ) is a common air pollutant and it has natural (as soil emissions or forest fires, for example) and anthropogenic sources.…”

Effects of the COVID-19 Pandemic on the Air Quality of the Metropolitan Region of São Paulo: Analysis Based on Satellite Data, Monitoring Stations and Records of Annual Average Daily Traffic Volumes on the Main Access Roads to the City

“…The first group of works mainly perform empirical analyses on the effects of social distancing due to COVID-19 from different perspectives [12,23,33,41,42,44,51,56,57]. The second group of reviewed studies considers the analysis of variables determining air quality improvement during COVID-19 confinement, which is particularly relevant for a better understanding of how those variables can be crucial for air quality improvement within the context of urban regions [8,11,17,26,52,58,59]. A third group of studies focuses on analyzing air quality improvement stimulated by different transport policies at urban regions learning from the COVID-19 scenarios developed to restrict mobility, with particular interest in reducing car traffic [13,14,27,[60][61][62].…”

“…From the beginning of the quarantine in the State of São Paulo, there was a decrease in the movement of people and vehicles on the streets, caused by the closing of several public establishments such as parks, shopping malls, bars, restaurants and by the implementation of remote work in several companies [11]. Improvements on air quality were observed in several urban centers around the world caused by the closing of non-essential activities [12][13][14].…”

COVID-19 as a game-changer? The impact of the pandemic on urban trajectories

“… Morfeld et al (2021) were amongst the first to detect larger EM for Italian cities vis-à-vis the rest of the country. Potential reasons for higher EM in urban areas identified in the literature include higher air pollution ( Kephart et al, 2021 ), limited access to open green space ( Borna et al, 2022 ), high population density (Khavarian-Garmsir et al, 2021), and higher inequalities in terms educational attainment, income, and age ( Alfaro et al, 2022 ; Surendra et al, 2022 ), particularly in the context of fragile public health systems.…”