The New York Times reports:
The billowing clouds of tear gas that the authorities are sending through protest crowds across the United States may increase the risk that the coronavirus could spread through the gatherings.
Along with the immediate pain that can cause watering eyes and burning throats, tear gas may cause damage to people’s lungs and make them more susceptible to getting a respiratory illness, according to studies on the risks of exposure. The gas can also incite coughing, which can further spread the virus from an infected person.
Sven-Eric Jordt, a researcher at Duke University who has studied the effects of tear gas agents, said he had been shocked to watch how much the authorities had turned to the control method in recent days. “I’m really concerned that this might catalyze a new wave of Covid-19,” Mr. Jordt said.