A group of youngsters dressed as ghouls and zombies for Halloween parade in downtown Lisbon, Portugal, Friday, October 31, 2014. (Photo by Francisco Seco/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)

A group of costumed fans attend Comic-Con International at San Diego Convention Center on July 12, 2015 in San Diego, California. (Photo by Daniel Knighton/Getty Images)

Kung Fu master Li Liangui practices “Suogugong” Kung Fu and his wife Liang Xiaoyan (R) practices Qigong at a park in Beijing, China, June 30, 2016. For 50 years, kung fu master Li Liangui has been contorting his body into eye-watering positions while practising one of the more unusual and less popular Chinese martial art forms. The 70-year-old is an expert in suogugong, or body shrinking kung fu, where practitioners dislocate their bones to help them achieve unlikely positions and feats. (Photo by Kim Kyung-Hoon/Reuters)

An anti-Gaddafi fighter tests an anti-aircraft gun southwest of Sirte, Libya one of Muammar Gaddafi's last remaining strongholds, September 16, 2011. A timeline of images dating from 2010 from Sirte, Libya, the home town of deposed Libyan leader Muammar Gaddafi. Libyan forces battling Islamic State in the city of Sirte say they have defeated the militant group after months of street to street fighting backed by U.S. air strikes. Islamic State took control of the city more than a year ago and set up its main base outside Syria and Iraq. (Photo by Goran Tomasevic/Reuters)

Traffic enforcer Ramiro Hinojas, 51, wears a Santa Claus costume while directing motorists through traffic at an intersection in Pasay City, Metro Manila, Philippines on November 28, 2017. (Photo by Romeo Ranoco/Reuters)

An Indian Hindu devotee celebrates Holi, the spring festival of colours, during a traditional gathering at a temple in Nandgaon village in Uttar Pradesh state on March 16, 2019. Holi, the popular Hindu spring festival of colours is observed in India at the end of the winter season on the last full moon of the lunar month. (Photo by Noemi Cassanelli/AFP Photo)

China Airlines stewardess Wang Wen Hwang leaps from the burning China Airlines plane after assisting the passengers to safety February 27, 1980. Miss Wang saved most of the lives of the passengers despite her injuries. She was the last to leave the planes. (Photo by AP Photo)