Air Pollution Linked to High Coronavirus Death Rates
Coronavirus patients in areas with high air pollution are more likely to die from the infection. Here’s what you need to know—and some tips on reducing exposure to pollution.
One recent New York Times article explores a new study that suggests that coronavirus patients in areas with high air pollution are more likely to die than patients in cleaner parts of the country. This is the first clear link between long-term exposure to pollution and COVID-19 death rates.
Researchers at Harvard University T.H. Chan School of Public Health The study analyzed 3,080 counties in the U.S. and found that higher levels of particulate matter (PM) 2.5—the tiny, dangerous particles in the air—were associated with higher death rates from the disease.
The suspected link between dirty air and death or serious illness from COVID-19 is not new. For weeks, public health officials suspected a connection, but the Harvard analysis is the first nationwide study to show a statistical link. The study revealed a “large overlap” between coronavirus-related deaths and other diseases associated with long-term exposure to fine particulate matter.
“The results of this paper suggest that long-term exposure to air pollution increases vulnerability to experiencing the most severe Covid-19 outcomes,” the authors wrote.
The paper found that if Manhattan had lowered it average particulate matter level by one single unit, or one microgram per cubic meter, over the past 20 years, the study suspects it could have seen 248 fewer COVID-19 deaths by this point in the pandemic.
There are a number of factors that can increase a person’s susceptibility to severe coronavirus-related illness. Those at high risk are those with compromised immune systems, older individuals with preexisting health conditions, and those with respiratory difficulties—which could be related to asthma, smoking or other lung complications.
However, the study did account for factors like smoking rates and population density. Still, the study found that just a slight increase in long-term pollution exposure could have serious coronavirus-related consequences.
The New York Times piece provided the study’s example that a person living for decades in a country with high levels of fine particulate matter is 15 percent more likely to die from the virus than someone in a region with one unit less of the fine particulate pollution.
The District of Columbia is likely to have a higher death rate than adjacent counties in Maryland, Chicago, places of Georgia and more.
Where Does PM Come From? How Does it Relate to Respiratory Issues?
Most fine particulate matter comes from fuel combustion—automobiles, refineries, power plants and some indoor sources like tobacco smoke.
Breathing in the microscopic pollutants inflames and damages the lining of the lungs over time, which weakens the body’s ability to fend off respiratory infections.
A number of studies have found that exposure to fine particulate matter puts people at heightened risk for lung cancer, heart attacks, strokes and even premature death. In 2003, Dr. Zuo-Fang Zhang found that SARS patients in the most polluted parts of China were nearly twice as likely to die from the disease than those in places with low air pollution.
Dr. Zhang called the Harvard study “very much consistent” with his findings.
How Will this Study Help?
The study will at least serve to warn cities with high populations and high particulate matter levels that they will likely see higher numbers of hospitalizations and deaths. Researchers also hope the study will help public health officials choose how to allocate resources (like ventilators and respirators) as coronavirus spreads.
“This study provides evidence that counties that have more polluted air will experience higher risks of death for Covid-19,” said Francesca Dominici, a professor of biostatistics at Harvard who led the study.
There are a number of efforts—mainly out of Europe—that offers a view into how a lifetime of breathing in dirtier air can make people more susceptible to the coronavirus, which has already killed more than 10,000 people in the U.S. and 74,000 worldwide—as of April 4, 2020.
There are other aspirations for what this study will do for communities and public health officials. Dr. John R. Balmes is a spokesman for the American Lung Association and professor of medicine. He said the findings were especially important for hospitals in poor neighborhoods and communities of color—which tend to be exposed to higher levels of air pollution than affluent, white communities.
“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,” Dr. Balmes said.
Some are hoping that the study will have implications for clean-air regulations. The study itself calls for more aggressive attention on increasing air pollution regulations: “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 Study
Researchers collected particulate matter data for the past 17 years from over 3,000 counties and COVID-19 death counts for each county through April 4 from the Center for Systems Science and Engineering Coronavirus Resources Center at the John Hopkins University.
The model examines aggregated rather than individual data, suggested what Dr. Dominici called a statistically significant link between pollution and coronavirus deaths.
Researchers conducted six secondary analyses to adjust for factors they felt might impact results. For example, they conducted certain analyses to account for New York (with already high death rates, coronavirus cases and pollution) as well as counties with fewer than 10 cases. They also adjusted for various other factors that are known to affect health outcomes like smoking rates, population density and poverty levels.
The study still needs to be submitted for peer review and publication in the New England Journal of Medicine. However, Dr. Dominici noted, the findings are valuable.
Preventing Air Pollution in Your Home
Lastly, while avoiding pollution and particulate matter is not always an easy fix—especially if you live in highly polluted areas or near factories—here are a few tips to reducing your exposure to pollution and particulate matter.
- You can make changes to your morning commute in your car, like adjusting air vents.
- You can reduce cigarette smoke in your home or workspace—especially if there are children in your home.
- You can use air filters in your office, workplace or home to better filter your air and measure particulate matter levels.
- Avoid excessive idling in your automobile—and walk, ride a bike or use public transit when possible.
- Use electric or hand-powered lawn care equipment.