Higher rates of air pollution linked to more COVID-19 deaths, study shows

A Harvard study finds even slightly higher levels were “associated with a 15% increase in the COVID-19 death rate”

By Igor Derysh

Managing Editor

Published April 12, 2020 8:00AM (EDT)

A pall of smog lies over the Los Angeles skyline. (AP Photo/Nick Ut)
A pall of smog lies over the Los Angeles skyline. (AP Photo/Nick Ut)

Areas of the United States with higher levels of air pollution experience higher COVID-19 death rates than areas with cleaner air, according to a study by researchers at Harvard University.

Researchers at Harvard's T.H. Chan School of Public Health analyzed 3,080 counties and found that even slightly elevated levels of tiny particles known as PM 2.5 — meaning 2.5 micron-wide pollutants — were linked to higher death rates. PM 2.5 particles are emitted from vehicle exhaust and coal power plants. PM 2.5 exposure has long been linked to higher rates of heart disease, diabetes, and respiratory illnesses, which have all been linked to a higher risk of severe illness and death from COVID-19. Nearly 80% of patients requiring intensive care treatment have at least one of the three types of conditions.

The researchers found that an increase of just one unit of PM 2.5 was "associated with a 15% increase in the COVID-19 death rate."

The study included multiple secondary analyses and controlled for factors like household income, population, hospital capacity, and smoking rates. Researchers noted that it was difficult to "accurately quantify the number of COVID-19 cases due to limited testing capacity."

"The results of this paper suggest that long-term exposure to air pollution increases vulnerability to experiencing the most severe Covid-19 outcomes," the researchers wrote.

"This study provides evidence that counties that have more polluted air will experience higher risks of death for Covid-19," lead researcher Francesca Dominici, a biostatistics professor, told The New York Times, adding that counties with higher pollution levels "will be the ones that will have higher numbers of hospitalizations, higher numbers of deaths and where many of the resources should be concentrated."

The study demonstrates the importance of clean air regulations, which the Trump administration has relentlessly worked to roll back in the years preceding the pandemic.

Indeed, the administration last week rolled back vehicle tailpipe emissions regulations even after the Department of Transportation and the Environmental Protection Agency (EPA) found that doing so would result in higher death rates. The EPA similarly found that its decision to gut coal power plant regulations would lead to as many as 1,400 annual premature deaths.

"The study results underscore the importance of continuing to enforce existing air pollution regulations to protect human health both during and after the Covid-19 crisis," the Harvard researchers warned in the new study.

The new findings echo the conclusions of past research on air pollution, which the World Health Organization blames for about 7 million deaths each year.

An analysis published in the journal Environmental Pollution similarly found a correlation between pollution rates and death rates in northern Italy, where up to 12% of patients have died from COVID-19.

Moreover, researchers at Cambridge University found that the 1918 flu pandemic, the deadliest in history, killed more people in cities that burned more coal compared to cities that did not.

A 2003 study led by Dr. Zuo-Fend Zhang, the associate dean of research at UCLA's Fielding School of Public Health, found that SARS patients in parts of China with the highest pollution rates were twice as likely to die from the virus than those who lived in areas with lower rates.

Zhang told The Times that the new Harvard research was "very much consistent" with his findings.

Dr. John Balmes, a professor of medicine at the University of California, San Francisco who serves as a spokesman for the American Lung Association, told the outlet he was concerned about what the findings mean for poor neighborhoods and communities of color, which tend to have higher levels of air pollution.

"We need to make sure that hospitals taking care of folks who are more vulnerable and with even greater air pollution exposure have the resources they need," he said.

A study by scientists at the Environmental Protection Agency found in 2018 that poor neighborhoods had about 135% as much air pollution as the overall population and black communities had 154% as much air pollution as the overall population.

"Communities of color, they've always been the sacrifice zones," Mustafa Ali, who led the environmental justice program at the EPA under President Obama, said in a video this week. "They've been the places where we've pushed things that nobody else wants."

Ali, who now works on environmental justice issues at the National Wildlife Federation pointed to data showing that black people are far more likely to die from the coronavirus. In areas like Chicago and Louisiana, black people make up roughly 70% of COVID-19 deaths despite making up just a third of the population.

Dr. Anthony Fauci, the director of the National Institute of Allergy and Infectious Diseases, said this week that, much like the longstanding issue of air pollution, black Americans are more affected by the virus because of long-running health disparities.

"When you're in the middle of a crisis, like we are now with the coronavirus, it really does… shine a very bright light on some of the real weaknesses and foibles in our society," Fauci said. "Health disparities have always existed for the African American community. But… it's shining a bright light on how unacceptable that is."

Though racial data on virus deaths is still limited, Fauci pointed to the prevalence of "underlying medical conditions — the diabetes, the hypertension, the obesity, the asthma" as the cause for the higher death rate. "The underlying reason why that is happening does not change from state to state," he added.

Dr. Uche' Blackstock, an emergency physician at New York University's Langone Health and the founder of Advancing Health Equity, agreed that the startling number of deaths among black Americans was not caused by the coronavirus alone but by decades of systemic inequality.

"This pandemic will likely magnify and further reinforce racialized health inequities, which have been both persistent and profound over the last five decades, and Black Americans have experienced the worst health outcomes of any racial group," she wrote in an op-ed at the Scientific American. "Black Americans will be more vulnerable to the consequences of the COVID-19 pandemic because of several manifestations of structural racism, including lack of access to testing, a higher chronic disease burden and racial bias within health care institutions."

But what is to be done in the middle of a pandemic? Fauci argued that "there's nothing we can do right now other than try to give them the best possible care to avoid complications."

New York City has taken a more proactive approach, launching a multimillion-dollar campaign to reach minority communities with information about the virus. New York state has also launched a similar awareness campaign.

Dr. Patrice Harris, the president of the American Medical Association, urged local officials to go further. Harris called for cities to implement housing policies to protect frontline workers, many of whom are black and Hispanic, and to ramp up efforts to ensure they have the necessary protective equipment.

Dr. Oliver Brooks, the president of the National Medical Association, called to expand access to health technology, including remote monitoring tools for chronic diseases. "We must create a data repository overseen by a credible organization to ensure data are consistently accessible to everyone," he said.

Ultimately, the first step in any effort will be to make the data available. Spencer Overton, the president of the Joint Center for Political and Economic Studies, said in a Washington Post op-ed that collecting and publishing race data throughout the entire country is necessary to educate the public and inform lawmakers.

"The disproportionate impact appears to be attributable to preexisting conditions — high blood pressure, heart disease, diabetes and inadequate access to health care — that make African Americans more vulnerable to the disease," he wrote. "But the handful of examples above raises an urgent question: Does the effect hold true for African Americans throughout the country? Unfortunately, there's no way for the public to know."


By Igor Derysh

Igor Derysh is Salon's managing editor. His work has also appeared in the Los Angeles Times, Chicago Tribune, Boston Herald and Baltimore Sun.

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Aggregate Air Pollution Anthony Fauci Coronavirus