Riot police fire tear gas at demonstrators during a protest against fare hikes for city buses in Sao Paulo, Brazil, January 8, 2016. Brazilian riot police on Friday fired tear gas and stun grenades to disperse a violent protest against a rise in public transport fares in the country's largest city, Sao Paulo. (Photo by Nacho Doce/Reuters)

Gas-masked men of the British Machine Gun Corps with a Vickers machine gun during the first battle of the Somme, 1916. (Photo by General Photographic Agency/Getty Images)

A man wears a gas mask as he holds a bouquet of flowers, following the outbreak of the novel coronavirus on Valentine’s Day in Hong Kong, China on February 14, 2020. (Photo by Tyrone Siu/Reuters)

A police officer fires tear gas at protesters after the presidential election results were announced in Kisumu, Kenya on August 15, 2022. (Photo by Baz Ratner/Reuters)

Winton Elementary fifth graders Juliana Ragan, from left, Chloe Windsor and Paisley Ganske wait backstage for their turn to perform as the Andrew Sisters during the Pearl Harbor/Veterans assembly at the school on Monday, December 7, 2015, in Coeur d'Alene, Idaho. Dec. 7 is the 74th anniversary of the Japanese bombing of Pearl Harbor. (Photo by Kathy Plonka/The Spokesman-Review via AP Photo)

A soldier poses with a Hythe Mk III Gun Camera during training activities at Ellington Field, Houston, Texas in April of 1918. The Mk III, built to match the size, handling, and weight of a Lewis Gun, was used to train aerial gunners, recording a photograph when the trigger was pulled, for later review, when an instructor could coach trainees on better aiming strategies. (Photo by Harry Kidd/WWI Army Signal Corps Photograph Collection via The Atlantic)

Members of the Edo Firemanship Preservation Association balance on top of bamboo ladders during a demonstration at the New Year's fire review held by the Tokyo Fire Department in Tokyo, Japan, 06 January 2016. Some 2,800 firefighters perform various emergency rescue and firefighting demonstrations in an effort to promote the prevention of fire and disaster in the annual event. (Photo by Kiyoshi Ota/EPA)

Fans of Gimnasia de La Plata choke on tear gas during a local tournament match between Gimnasia de La Plata and Boca Juniors in La Plata, Argentina, Thursday, October 6, 2022. The match was suspended after tear gas thrown by the police outside the stadium wafted inside affecting the players as well as fans who fled to the field to avoid its effects. (Photo by Gustavo Garello/AP Photo)