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)

Brush your teeth and get cleaned up for the week ahead! These animals answered the call of good dental hygiene. Here: Hamster holds toothbrush. (Photo by Neo Vision/Getty Images/Amana Images RM)

A Hindu woman worships the Sun god in the waters of a lake during the religious festival of Chhath Puja in Agartala, India, November 13, 2018. (Photo by Jayanta Dey/Reuters)

UK Love Island's star Megan Barton Hanson, 26, looked incredible as she stripped off for a very sеxy shoot to mark her return to Only Fans on March 20, 2020. The latest pictures see the stunning star pulling a range of poses while wearing just yellow thong lingerie and a pair of black boots. (Photo by Backgrid UK)

A military helicopter flies over people during the Afghan Security Forces Exhibition, at the Darul Aman Palace in Kabul, Afghanistan, Wednesday, March 3, 2021. The three-day military exhibition in Kabul allowed civilians to have a first hand view and take pictures of weaponry used by Afghan Security forces. (Photo by Rahmat Gul/AP Photo)

Saudi female firearm trainer, Mona Al Khurais, teaches a Saudi boy on safe usage of weapons at the Top-Gun shooting range in Riyadh, Saudi Arabia, October 28, 2021. (Photo by Ahmed Yosri/Reuters)

A mask seller wearing a mask stands in a street market in Bangkok, Thailand, Tuesday, June 9, 2020. Daily life in capital resuming to normal as Thai government continues to ease restrictions related to running business in capital Bangkok that were imposed weeks ago to combat the spread of COVID-19. (Photo by Gemunu Amarasinghe/AP Photo)

Supporters of Lebanese President Michel Aoun hold up a giant Lebanese flag as he delivers a speech outside the presidential palace in Baabda, east of Beirut, Lebanon, Sunday, October 30, 2022. Aoun left Lebanon's presidential palace Sunday marking the end of his six-year term without a replacement, leaving the small nation in a political vacuum that is likely to worsen its historic economic meltdown. (Photo by Bilal Hussein/AP Photo)