COVID-19 and air quality: A call to address health effects, racial disparities
There is growing evidence on connections between COVID-19, air pollution and racial disparities.
Because COVID-19 targets an individual’s respiratory system, it is crucial to eliminate racial and health disparities and reduce air pollution in the U.S. to mitigate the pandemic.
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The American Lung Association recently held a virtual Town Hall to discuss the connections, health impacts and racial disparities in air quality and COVID-19. Researchers and experts discussed the implications of preliminary findings that suggest higher COVID-19 mortality in individuals with long-term exposure to poor air quality and findings that Black individuals and other racial groups are at especially high risk for the health effects of COVID-19 and air pollution.
Effects of increased pollution
There are an estimated 21,800 toxic release inventory sites in the United States. Toxic release inventory sites are industrial and federal facilities that release pollution and developmental neurotoxins. Most of these sites are located in large population centers; two-thirds of Americans, or 200 million people, live within 3 miles of a toxic release inventory site and more than 60 million people live within 1 mile of a site, according to Claudia L. Persico, PhD, assistant professor in the department of public administration and policy at American University.
On March 26, the U.S. Environmental Protection Agency suspended civil enforcement of environmental regulations on monitoring pollution during the COVID-19 pandemic. Persico and colleagues conducted a study to evaluate whether the EPA’s rollback of environmental enforcement led to increases in pollution, whether exposure to local industrial pollution affected COVID-19 cases and deaths, and whether pollution exposure affected outcomes differentially by race and socioeconomic status.
“While we ... might believe that this pandemic lowered pollution everywhere, that in fact has not been true, and in some places, actually, pollution increased substantially because of this rollback,” Persico said. “Particularly, it increased in the places where there are more factories and power plants.”
Persico and colleagues used county-level data from the Center for Systems Science and Engineering at Johns Hopkins University on COVID-19 outcomes matched to data from the EPA on air pollution and toxic release inventory sites, data from the National Oceanic and Atmospheric Administration on weather, and data from Unacast on social distancing. Researchers compared counties with more toxic release inventory sites vs. counties with fewer toxic release inventory sites before and after the EPA rollback. Using a within-county difference in differences design, researchers estimated whether counties with six or more sites experienced increased pollution due to the rollback and whether it affected increases in COVID-19 cases and deaths compared with counties with fewer toxic release inventory sites.
Results showed a 13% increase in fine particulate matter pollution, or about 0.8 µg/m3, in counties with six or more toxic release sites, a 15% increase in particulate matter with a diameter less than 10 µm (PM10) pollution and a 5% increase in ozone. In areas with more toxic release inventory sites, the amount of particulate matter produced in the air and the number of COVID-19 deaths increased. During the study period, there was a 38.8% increase in daily COVID-19 cases and a 19.1% increase in daily COVID-19 deaths.
In addition, Persico described worse effects of pollution and COVID-19 infection and mortality rates in counties with higher populations of Black individuals compared with counties with a higher population of white individuals. The researchers found a 21.6% increase in daily COVID-19 deaths in the counties with a higher population of Black residents vs. a 5% increase in counties with a higher population of white residents.
“Not only was there an increase in pollution, but this increase in pollution actually contributed to a worsening of the pandemic,” Persico said. “There are a variety of different types of counties scattered throughout the United States that have more heavy industry and experienced more pollution after the rollback and then the pandemic worsened greatly in those locations.”
Pollution and racial inequity
There is a “very long list” of adverse health outcomes associated with exposure to fine particulate matter from all around the world, Francesca Dominici, PhD, director of the Harvard Data Science Initiative and professor of biostatistics, population health and data science at Harvard University, said during a presentation.
Dominici and colleagues previously published data that demonstrated long-term exposure to fine particulate matter, even at a level below the national ambient air quality standard of 12 µg/m3, increased the risk for mortality.
“Even though levels of air pollution in [the United States] have been decreasing over time, the level of inaction, racial inequity and socioeconomic inequity are actually increasing over time. We are not cleaning the air consistently for everyone,” Dominici said.
In the past 20 years, the U.S. has made progress in lowering levels of pollution, with a 43% decrease in fine particulate matter from 2000 to 2016. However, inequities in exposure to fine particulate matter among different racial groups appear to be increasing.
Moreover, researchers hypothesize that people with long-term exposure to fine particulate matter have a greater susceptibility for COVID-19-related mortality. Dominici highlighted a previous study from her group that showed a significant association between fine particulate matter exposure and acute respiratory distress syndrome, which is one of the main causes of death related to COVID-19.
Dominici and colleagues gathered data from more than 20 national databases and developed statistical approaches to assess the link between long-term exposure to fine particulate matter and COVID-19 mortality rate at a county level.
When comparing similar counties, researchers found that those living in counties with a higher level of long-term exposure to fine particulate matter had an 11% greater risk of COVID-19 mortality.
Further, U.S. counties in the U.S. with higher fine particulate matter exposure also have a higher population of Black individuals. In many areas of the U.S., the Black population is still living with high PM2.5 levels, according to Dominici. From 2010 to 2016, inequalities in the exposure to PM2.5 levels above 8 ug/m3 across racial/ethnic and income groups increased by factors of 1.58, she said.
The researchers also found a 49% increase in the COVID-19 mortality rate in areas with increased fine particulate matter that had a higher Black population.
“When we look at the relationship between areas that are predominantly African American and the COVID-19 mortality rate, we found that African Americans are much more susceptible to die from COVID-19,” Dominici said. “This link might be plausible and, therefore, we need further research.”
Racial disparities in COVID-19 infection rates
There is increasing evidence that certain racial and ethnic groups are disproportionately affected by COVID-19, according to Tesfaye Mersha, PhD, associate professor in human genetics at the Cincinnati Children’s Hospital Medical Center in the department of pediatrics at the University of Cincinnati College of Medicine.
Mersha highlighted recent data from APM Research that show the U.S. age-adjusted death rate for COVID-19 is 70 per 100,000 for Black individuals compared with 34 per 100,000 for Hispanic individuals, 30.2 per 100,000 for white individuals and 29 per 100,000 for Asian individuals.
“Risks of COVID-19 exposure are not evenly distributed,” Mersha said. “We need to address socioeconomical disparities.”
Mersha and colleagues evaluated ZIP code level data for more than 91,000 confirmed cases of COVID-19 in Illinois. Counties with higher confirmed COVID-19 cases had a higher percentage of Black residents and a higher percentage of food stamp recipients, whereas counties with lower confirmed COVID-19 cases had more white residents and fewer food stamp recipients.
Exposure to fine particulate matter pollution and COVID-19 infection rates overlap in many minority populations within the U.S., Mersha said. In a study by Tessum and colleagues published in PNAS, Black individuals were exposed to greater than 56% of pollution than what they contribute and Hispanic individuals were exposed to greater than 60% pollution exposure, whereas white individuals were exposed to less than 17% pollution than what they contribute.
“There is a lot of interest in looking at the [angiotensin-converting enzyme]-2 gene, which is linked to COVID, but [another] interesting thing is the link between air pollution and COVID-19. It actually has to do with where we live, the ZIP code, income, the housing environment — which, combined, compromise the respiratory system and, of course, [may] worsen COVID-19 outcome,” Mersha said.
Multilevel interventions are needed to address these racial disparities, Mersha said.
We need to tackle this problem, not just what we see from one side, but rather on the individual level, at the neighborhood level, community level and at the state or government level. It really is a multilevel effort that can contribute to the slowdown [of COVID-19] and eliminate these disparities,” Mersha said.
References:
- American Lung Association. Stand Up for Clean Air. www.lung.org/air.
- APM Research Lab. The Color of Coronavirus. July 22, 2020.
- Brandt EB, et al. J Allergy Clin Immunol. 2020;doi:10.1016/j.jaci.2020.04.035.
- Persico C, et al. SSRN. 2020;3633446.
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- Wu X, et al. medRxiv. 2020;doi:10.1101/2020.04.05.20054502.