November 19th was World Toilet Day, an effort — through a United Nations agency known as UN-Water — to raise awareness of the fact that 2.4 billion people around the world do not have access to improved toilets and sanitation.

In fact, more people worldwide have mobile phones than toilets. It's a problem that especially affects the health of women and children.

Getting rid of our waste is an issue that goes back 10,000 years, to when we entered the Neolithic or "New Stone Age." For various reasons, people changed their behaviour from a hunting and food-gathering lifestyle, to tilling the land. Spears were replaced by hoes. The birth of agriculture meant people stayed in one place, gathered in villages that grew into towns, that grew into cities, that spawned our modern civilization.

But throughout most of that remarkable development and resulting population explosion, waste management has been an issue that just hasn't gone away.

World Toilet Day Cape Town SA Oct 2015

Temporary toilets stand in front of shacks in Khayelitsha township, Cape Town, South Africa.

Toilets, in some form, have been around since the time of the Ancient Greeks and Romans. But their function was to simply move the waste out of the home, using water that was poured into gutters or sewers and eventually ended up in rivers, which supposedly carried it away.

That "out of sight, out of mind" philosophy backfired, because those same rivers were also used for drinking water and preparation of food. Throughout the ages, epidemics such as cholera and plagues have claimed millions of lives, largely due to poor sanitation.

In fact, the introduction of proper water treatment has been a major contributor to extending human life expectancy.

Sadly, this technological fix for a global health problem has not reached more than a quarter of the world's population. According to UN documents, "Stark inequalities in access to toilets threaten the survival, health, safety, and dignity of vulnerable populations, despite their human right to water and sanitation."

While the spread of disease is still a major concern, a surprising impact of poor sanitation is malnutrition. Children who are exposed to contaminated water can develop chronic diarrhea and intestinal worms. Their bodies cannot absorb nutrients from food as well, resulting in stunted growth and poor health. If those children later become mothers with stunted growth, their babies will be underweight as well, and so the vicious cycle continues.  

In other words, sending clean water technology to the developing world is more valuable than sending food.

World Toilet Day outhouse Lima Peru Oct 2015

A toilet stands outside a home in Villa Maria del Triunfo on the outskirts of Lima, Peru. (Mariana Bazo/Reuters)

The UN considers clean water a major issue of the 21st century. Since 2000, the Millennium Development Goals were set to bring proper sanitation and clean water to developing nations. While more than a billion people have benefited from this program, it fell short of its goal by 700 million people.

This week, the UN Secretary General's Advisory Board on Water and Sanitation, UNSGAB, released its latest report on the need for adequate sanitation, healthy aquatic ecosystems, and sound water management, to ensure sustainable development by 2030.

Here in the West, toilets are often the source of humour. Even the sound of a flushing toilet can get a laugh. But for more than one quarter of the world's population, it's no joke. In fact, the sound of a flush would be most welcome music to their ears.