Two women look at a mobile phone as they stand on Tiananmen Square during a sand storm in heavily polluted weather in Beijing on February 28, 2013. Beijing residents were urged to stay indoors as pollution levels soared before a sandstorm brought further misery to China's capital. (Photo by Ed Jones/AFP Photo)

Participants try to cover themselves from color powder sprayed by volunteers as they run through a “color station” during a five-kilometer color run event held in Beijing, China Saturday, June 21, 2014. (Photo by Andy Wong/AP Photo)

Yang Shiguang, 77, performs stunts at a park in Xi'an, Shaanxi province, September 3, 2013. Yang has been a member of a stunt performance club since 2007, after retiring from a research institution. (Photo by Reuters/China Daily)

Vehicles clog a highway during a hazy day in Beijing, China, Wednesday, February 26, 2014. Beijing remained cloaked in hazardous white pollution hiding much of its skyline Wednesday, despite the announced closures or production cuts at 147 of the city's industrial plants. (Photo by Ng Han Guan/AP Photo)

Buns are stamped the Chinese characters “Ping An”, meaning peaceful and safe, inside a bakery, at Hong Kong's Cheung Chau island, China May 17, 2015, ahead of the upcoming Bun Festival on May 25. The festival celebrates the islanders' deliverance from famine many centuries ago and is meant to placate ghosts and restless spirits. (Photo by Tyrone Siu/Reuters)

Emma Coburn (L) and Colleen Quigley of the U.S. look at the scoreboard after competing in the women's 3,000 metres steeplechase final during the 15th IAAF World Championships at the National Stadium in Beijing, China August 26, 2015. (Photo by David Gray/Reuters)

Frost covers a face shield of a volunteer before the start of the women's 7.5km + 7.5km skiathlon cross-country skiing competition at the 2022 Winter Olympics, Saturday, February 5, 2022, in Zhangjiakou, China. (Photo by Alessandra Tarantino/AP Photo)

Itzhak de Laat of Team Netherlands crashes during the Men's 500m Heats on day seven of the Beijing 2022 Winter Olympic Games at Capital Indoor Stadium on February 11, 2022 in Beijing, China. (Photo by Toby Melville/Reuters)