A man pours mud water on the head of his girl friend during the Boryeong Mud Festival at Daecheon Beach in Boryeong, South Korea, Friday, July 18, 2014. The annual mud festival features mud wrestling and mud sliding. (Photo by Ahn Young-joon/AP Photo)

Growing cities, overuse of fertilizers and factory wastewater have degraded China's water supplies to the extent that half the nation's rivers and lakes are severely polluted. China aims to spend $850 billion to improve filthy water supplies over the next decade, but even such huge outlays may do little to reverse damage caused by decades of pollution and overuse in Beijing's push for rapid economic growth. Photo: Fishermen row a boat in the algae-filled Chaohu Lake in Hefei, Anhui province, June 19, 2009. (Photo by Jianan Yu/Reuters)

Dancers learn choreography they will need to perform as part of an open audition for the 2022 Radio City Rockettes at Radio City Music Hall in New York, New York, USA, 18 April 2022. The open auditions, the first being held since the start of the coronavirus pandemic, were expected to draw nearly 900 dancers competing for one of the few open spots in the 2022 Christmas Spectacular Starring the Radio City Rockettes, a long running holiday show. (Photo by Justin Lane/EPA/EFE)

Runners high-five children cheering from the sidewalk as they begin the half marathon during the Ottawa Race Weekend, which returned from a two-year hiatus due to the COVID-19 pandemic in Ottawa, Canada on Sunday, May 29, 2022. (Photo by Canadian Press/Rex Features/Shutterstock)

Revellers dressed in mock military garb take part in “Els Enfarinats” food-battle in the southeastern Spanish town of Ibi on December 28, 2022. (Photo by Jaime Reina/AFP Photo)

Indian labourers carry clay bricks to a brick kiln in Farakka, in the Indian state of West Bengal, on April 3, 2019. (Photo by Xavier Galiana/AFP Photo)

Anti-racist Loldiers of Odin clowns speak with police as they take to the streets against anti-immigration marchers in Tampere, Finland January 23, 2016. Police prevented the groups from confronting each other. On the northern fringes of Europe, Finland has little history of welcoming large numbers of refugees, unlike neighbouring Sweden. But as with other European countries, it is now struggling with a huge increase in asylum seekers and the authorities are wary of any anti-immigrant vigilantism. (Photo by Kalle Parkkinen/Reuters/Lehtikuva)

Germany's Angelique Kerber reacts after popping a bottle of champagne, a day following her win in the final match at the Australian Open tennis tournament, at the Government House in Melbourne, Australia, January 31, 2016. (Photo by Issei Kato/Reuters)