Over the years, scientists have linked all sorts of health issues to changes in the environment caused by everyday air pollutants, like the exhaust from your car.
About 17% of U.S. emissions come from day-to-day commuting and light trucks.
But now in some parts of the country, pollution from driving has been cut in half, due in large part to the coronavirus lockdowns that ban unnecessary travel.
In California, driving has dropped by 80%.
That’s according to professor of environmental health sciences Yifang Zhu at UCLA.
"We know from the literature, there's tons of evidence that pollutants from traffic sources have been linked to all sorts of health effects," said Zhu.
Scientists are still in the early stages of measuring the decline and its effect on our health. But what they've seen so far is promising.
"We haven't quantified anything, but I think just based on our previous knowledge, this is going to be a substantial benefit on health overall."
Research has shown reducing this pollution may also help crops grow better and reduce the rate of atmospheric warming in places.
But whether these benefits will last is harder to say. The coronavirus is reaching deep into the economy of transport, not just depressing driving but also taking U.S. auto plants offline and pushing down sales of new cars. But at the same time, emissions have a tendency to bounce back from major disruptions. That may only change if people change their habits.
"To what extent it will last, I think it really depends on how people behave after this pandemic, after the stay-at-home orders get lifted," Zhu said. "If people choose to go back to their business as usual, then the emissions will come back and air quality will come back to what it was before the pandemic."
"If we all embrace the sustainability solutions that society has technology-wise and policy-wise, then this type of cleaner air should be a norm rather than a result from a pandemic."