THE SURPRISINGLY FAST-ACTING BENEFITS OF CLEANER AIR

e’re accustomed to thinking of environmental change, and its attendant effects on our health, as being measured in years. But researchers are now discovering how quickly and dramatically air quality can improve—and how big an impact those improvements can make.

For instance, when Atlanta hosted the 1996 Olympic Games, parts of the city were closed to cars for 17 days. In the following four weeks, kids’ medical visits for asthma decreased by more than 40 percent. In 1990, when Hong Kong passed stricter regulations for the content of fuel oil used by power plants and cars, sulfur dioxide levels immediately fell by 45 percent on average and as much as 80 percent in the most polluted areas. Within six months, there was a significant decrease in the number of deaths from respiratory and cardiovascular diseases.

In March 2020, when businesses shut down because of the coronavirus pandemic, nitrogen dioxide levels were about 30 percent lower on average in the northeastern United States than they were in the same month for the years 2015 to 2019. Also, during the month that China was under quarantine because of the pandemic, one study estimated that improved air quality helped to prevent more than 12,000 pollution-related deaths. With a recent study showing that an increase of just one microgram per cubic meter of fine particulate matter is associated with an 8 percent increase in the COVID-19 death rate, measures to improve air quality may be more important than ever before.

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