Nearly half the world’s schools lack clean drinking water, toilets and handwashing facilities, putting millions of children at risk of disease, experts warned on Monday.
Almost 900 million children have to contend with a lack of basic hygiene facilities during their education, putting their health at risk and meaning some have to miss school.
"You can’t have a quality learning environment without these basics," said Rick Johnston of the World Health Organisation, a lead researcher on the project.
"Children may not come to school at all if there’s no toilets … Then, when they are at school, they are not going to at their very best if they not able to use a decent toilet or if they are not properly hydrated."
A lack of safe water and sanitation facilities can cause dehydration, illness, and even death.
It found nearly a third of primary and secondary schools lacked a safe and reliable drinking water supply, affecting nearly 570 million children.
Just over a third of schools lacked adequate toilet facilities, affecting more than 620 million children.
Sub-Saharan Africa, East and Southeast Asia had some of the worst facilities.
"It’s deeply shocking," Tim Wainwright, the chief executive of charity WaterAid, told the Thomson Reuters Foundation.
More than a third of girls in South Asia miss school during their periods, often because they lack access to toilets or pads, according to a WaterAid and UNICEF study earlier this year.