A new study by Harvard found that a higher level of long-term exposure to air pollution is associated with higher risks of COVID-19 deaths in the U.S. According to the authors, the results highlight the importance of enforcing air pollution regulations to protect human health during and after the  pandemic. This study offers empirical evidence on how air quality is linked to public health, and useful perspectives for how we should think about the benefits of climate action. 

The analysis looks at data from over 3,000 counties in the U.S. up to April 4, 2020 and investigates whether long-term exposure to fine particulate matter (PM2.5)– a harmful air pollutant that could cause health problems–increases the risk of COVID-19 deaths at a county level. These fine inhalable particles mostly come from power plants, industries, and automobiles. 

The study’s findings suggest that there is a statistical link between air pollution and risk of coronavirus deaths in the U.S. Based on the model results, an increase of 1 μg/m3 in PM2.5 is associated with a 15 percent increase in the COVID-19 death rate. The model controls for other factors such as population size, hospital beds, and variables including obesity and smoking. 

Dr. John R. Balmes, a spokesman for the American Lung Association, said the research findings are useful for hospitals in low-income communities and neighborhoods of color, which tend to be exposed to higher levels of air pollution, relative to “affluent, white communities.”

However, it is important to keep in mind that this is an early study performed in the midst of the ongoing pandemic. Future studies may in fact indicate that Harvard’s report either over or underestimates the link between air pollution and COVID deaths.

Another recent report indicates that 45.8 percent of the U.S. population lives in counties with unhealthy levels of ozone, or tiny particle pollution (like smog). The percentage numbers have increased over the last three years. Authors of the report believe that this rising trend is a result of climate change. Ground-level ozone, created by chemical reactions between pollutants that were emitted  from sources such as automobiles and power plants, is smog’s main ingredient

Climate action is a demonstrably effective way to reduce air pollution. Lowering the concentration of PM2.5 is one of the co-benefits of cutting carbon emissions. As analyzed by another recent study, reductions in carbon emissions would contribute to lower concentrations of PM2.5 in the air. 

Further studies on the link between air pollution and COVID-19 deaths need to be conducted after the pandemic when more data is available. Regardless, the Harvard study indicates that public health is an incredibly important aspect to consider in designing climate policies. There is little doubt that climate change will impact public health. Committing to decarbonization in the long run will help us reduce air pollution and improve public health outcomes.