Workers clean empty cooking oil containers at a roadside recycling workshop in Kolkata, India, July 13, 2016. (Photo by Rupak De Chowdhuri/Reuters)

A tourist poses on the glass-bottom bridge at Zhangjiajie Grand Canyon on August 20, 2016 in Zhangjiajie, Hunan Province of China. The Zhangjiajie Grand Canyon's glass-bottomed bridge welcame its trial operation on Saturday and about 8,000 tourists crowded to view the grand glass bridge. (Photo by VCG/VCG via Getty Images)

A man talks on his mobile phone in the village of Devmali in the desert state of Rajasthan, India June 14, 2016. (Photo by Himanshu Sharma/Reuters)

A housewife whose family lives in a shanty cooks beside a road in Manila, Philippines May 25, 2016. (Photo by Erik De Castro/Reuters)

A vendor prepares paan, a betel nut-based chewable stimulant at a flower market in Kolkata, India, January 18, 2016. (Photo by Rupak De Chowdhuri/Reuters)

Gigi Gorgeous presents a creation during the American Heart Association's (AHA) Go Red For Women Red Dress Collection, presented by Macy's at New York Fashion Week February 11, 2016. (Photo by Andrew Kelly/Reuters)

Performers Roni, Liv and Becky behind the scenes at Great Yarmouth Hippodrome Circus, England. (Photo by Nick Warner/The Guardian)

Iraqi teenagers swim in waste water from the nearby Tuweitha nuclear facility near Baghdad, Iraq on May 28, 2003. Iraqis are consuming contaminated water unaware of the dangerous pollutants that can cause severe ill health. (Photo by Damir Sagolj/Reuters)