A migrant labourer brushes his teeth in front of a scrapped helicopter model in Mumbai, India, April 13, 2016. (Photo by Danish Siddiqui/Reuters)

Women walk past a pile of rubbish bags on a street during a strike by garbage collectors demanding delayed salaries in Sanaa, Yemen May 8, 2017. (Photo by Khaled Abdullah/Reuters)

Costumed guests arrive for the “Life Ball” charity event at the Rathaus city hall in Vienna, Austria, 10 June 2017. The 24th Life Ball is a charity fundraiser for HIV and Aids projects. (Photo by Christian Bruna/EPA/EFE)

A woman poses as she beside David Hammons painting on an America flag “Injustice case” at the exhibition Soul Of A Nation, exploring the art made by African American artists between 1963 and 1983, in London, Tuesday, July 11, 2017. The exhibition starts on July 12, 2017 nd ends on Oct.22, 2017. (Photo by Frank Augstein/AP Photo)

A boy looks for sellable materials close to the burning garbage in the permanent waste land under Sylhet City Corporation for a living, on January 15, 2015. (Photo by Md. Akhlas Uddin/Pacific Press)

A Somali police officer arrests a suspected rebel member of the al Qaeda-affiliated al Shabaab among beach goers in Mogadishu. Al Shabaab claimed responsibility for today's pre-dawn attack on a Kenyan university campus near the Somali border. The following gallery examines who is al Shabaab. Here: Somali police officer (R) arrests a suspected rebel member (L) of the Al Qaeda-affiliated al Shabaab among beach goers at the Lido beach north of Somalia's capital Mogadishu March 23, 2012. (Photo by Feisal Omar/Reuters)

Breitling Wingwalkers aircrafts perform during an aerobatic display at an air show in Zhengzhou, Henan province, China, September 25, 201. (Photo by Reuters/Stringer)

A woman in traditional Malaysian attire welcomes leaders to the official dinner at the venue of the Association of Southeast Asian Nations (ASEAN) Summit in Kuala Lumpur, Malaysia November 21, 2015. (Photo by Jorge Silva/Reuters)