We eat, we drink, and whatever we put into our bodies, it comes out. And we cannot speak about it? It makes no sense. I don't say poop, I donít say toilet or excrement, because it doesn't help.
I wanna talk to you today about toilets. Weíre not allowed to say sh*t. And thatís part of the problem. We refuse the words because we refuse the reality.
On average, a human produces more than 70 kilos of excrement per year. Globally, that represents 550 million tonnes of waste which must be evacuated and treated. Excrement management worldwide poses a sanitation and ecological challenge which we almost never talk about.
And yet, you probably donít know that weíre experiencing a huge toilet revolution. 10 years ago, Bill Gates, who explores the world for his foundation, discovered that poop kills. According to the WHO, half of the worldís population doesnít have safe toilets. Nearly 700 million human beings defecate outside.
The problem is that poor sanitation causes diarrhea, dysentery, hepatitis A, and typhoid. It kills nearly 400,000 children each year. Bill Gates thought he could fix that by inventing a new kind of toilet for these countries. They smell terrible. No, thatís not the kind of toilet heís financing. In 2011, Bill Gates launched a major international competition called Reinvent the Toilet.
The toilet of the future must be able to remove all the harmful pathogens from human waste and recover resources like energy, clean water, and nutrients. They must also work without a network, without running water, and almost without electricity. To see these toilets financed by Gates, we went to Switzerland, to a kind of Harvard for pee, a university which specializes in separating fecal matter and urine in toilets in order to better recover all the good things contained in the liquid we produce. He wanted to come up with this new sanitation system, he consulted some friends and they came out with a system, how it could look like. How to use physical chemical processes, new processes to treat the excreta.
And he actually sent this sketch, this idea out with this invitation to participate to reinvent the toilet challenge. And it was extremely technological. I think something like supercritical water oxidation or electrolysis. This process really fit nicely in this picture, this plan.
The Eawag Institute is participating in Bill Gatesís competition because, for decades, they have been a global reference in research on water and sanitation. They invent a lot of machines and systems to turn urine into fertilizer. This is a urine separating toilet, safe, produced by love.
This is the collection tank where we collect the urine from this building. This is the biological reactor where we stabilize the urine. In this column, pharmaceuticals are removed with activated carbon.
After pharmaceutical removal, the urine is stored here and later brought to the distiller for concentration. This is the final fertilizer product, Aurin. At the outset, Eawag was going to call its fertilizer made from Swiss studentsí urine Urina. An in-house communications manager suggested they switch the letters to draw inspiration from the Latin word for Gold instead. Thatís why they chose Aurin. To be clear, the Eawag Institute separates urine and fecal matter and collects studentsí urine, because, Number One, itís easier to treat our waste when itís separated.
Number Two, most of the nutrients are concentrated in the urine. And most of the bacteriological bombs, the ones that kill children, are concentrated in the feces. One afternoon, we found ourselves at one of the biggest sh*t factories in the world. The Seine Aval wastewater treatment plant in Paris. Here you see the sludge produced at our facility. That pile is two days' worth.
The sludge will be carbonized, which will make it hygienic. Then we can spread it on agricultural fields. Have you got enough? The fact that people like Bill Gates want to invent almost dry toilets which separate urine and fecal matter always brings us back to one question.
Why did rich countries choose the flush toilet, which uses so much water, and a central sewer system terminating at a wastewater treatment plant? Until the mid-19th century, in major European cities, the most common custom was to empty your bucket out the window. The streets were so filthy that the scientists of the day ended up wondering if the bad odors themselves were causing the epidemics. That was called the miasma theory. In 1858, London was sweltering, and the level of the Thames, where all the excrement was dumped, was at its lowest.
The stench was so strong that the members of Parliament feared theyíd fall ill. It took powerful people smelling the odor for the tide to turn. This event, called The Great Stink, was the spark which launched a vast undertaking. The city was gutted to create a centralized sewer system.
Thousands of kilometers were dug at the same time in several major cities. Like in Paris, which had nearly 3,000 kilometers of sewer pipes. The same period saw the invention of the flush toilet, the height of efficiency when it came to making what you didnít want to see anymore disappear.
Disgust for fecal matter is a human constant. And our super-expensive and sophisticated system does all it can to evacuate excrement. Everyday we produce about 1 over liter of urine and about 200 grams of sh*t. Why do we want to add more gallons of water to make the problem bigger and then go and filter it out. It must be crazy.
When youíre working on the toilet issue, you constantly hear about Mister Toilet, a businessman in Singapore who, at the age of 40, realized that all he had done was accumulate money. Based on the life expectancy of a Singaporean man, he calculated how many days he had left to live, and he decided to devote them to a single cause - the revolution of sanitary facilities. So when I was 3 or 4 years old, we live in Kampong which is a slum village and we do not have toilet in our own house, the toilets is in a row of huts with a British bucket system. So you go up a few steps, you are squatting on the planks and then you poop into a bucket. When the bucket truck comes to collect it and replace it with a fresh new one, then everybody wants to go to the toilet.
But after a while it is full of other peopleís sh*t. And different colors... and then you have the sanitary pads with the blood, the toilet paper, and the flies immediately come.
It is very, very disgusting and very disturbing. Mister Toilet put all his weight behind the battle against sanitation inequality. He wanted the whole world to take on the issue. He founded the World Toilet Organization, through which he talks about poop on every continent. Over the last 10 years, the stars have aligned.
The UNís Sustainable Development Goals have put sanitation at the center of global concerns. For NGOs, for the people whoíve always worked in development, itís a toilet moment they feared would never come. The Bill Gates Foundation funded several studies, research labs, in the field of sanitation, to try to gather more data on this subject. I wasn't remotely shocked to see someone outside the field showing interest. It's always good to have a different kind of actor in the development sector, someone who challenges our own development practices.
There's a complementary dynamic in this kind of approach. All development experts will tell you: For decades, rich countries have been digging dry toilets in poor countries to bury waste. And they have a very hard time convincing states that itís a vital public-health issue. All that was true until 2 October 2014. Indian Prime Minister Narendra Modi chose Gandhiís birthday to announce the launch of the biggest-ever latrine-building campaign. In his speech, he said that a nation like India, which sends its own satellites into space, can no longer allow its people to relieve themselves outside.
The figures are stark. At the time, of the 900 million people in the world who had no sanitary facilities, 40% were Indian. Thatís not only due to the vastness of the country or its lack of infrastructure. The high prevalence of outdoor defecation in India is also due to a cultural problem. Dr. Pathak created Sulabh International, which wants to put an end to a tradition thatís lasted thousands of years in India.
The one which involves leaving the handling of poop to the Untouchable caste. When I was a child, I touched an Untouchable, and for that matter, my grandmother forced me to swallow cow dung and to drink cow urine. The ancient sacred texts of Hinduism required a man to defecate an arrowís flight from his home, and, if there was unfortunately excrement very close to your home, it was considered absolutely unclean to take care of it.
So, the Untouchables went from house to house to pick up your feces. In Rajasthan, I picked up people's fecal matter. When we were hungry or thirsty, people gave us water or leftover food, but without ever touching us. Or they'd toss some coins at our feet. We really suffered, but we couldn't do anything else.
It's what we've always done, generation after generation. There has never been another option for us. Had we tried to sell vegetables, no one would have bought them.
Dr. Pathak, himself a member of the very high Brahmin caste, decided to go against his own class interests and to break with tradition. Now, I'm at peace.
In New Delhi, his organization hosts a school for children of Untouchables. Everything is devoted to showing that excrement has value, that it can be used to make gas for cooking, for lighting, for feeding plants. Dr. Pathak wants to convince his fellow citizens that toilets are a desirable space and that you should have one at home rather than defecating outdoors.
He has even created a toilet museum. The business which generates the money for Dr. Pathakís organization is public pay toilets, thousands of which are spread all over India, employing more than 35,000 people. Heís even creating the Taj Mahal of public urinals. All this so that the Hindu culture of hating excrement no longer hinders toilet adoption.
In this matter, Dr. Pathak inspired Prime Minister Narendra Modi. The campaign is called Swachh Bharat, which means Clean India Mission. For its emblem, it uses Gandhiís little round glasses. Itís an unprecedented construction effort. Tens of millions of rudimentary dry toilets are being built in India. Itís also a massive communications campaign.
The prime minister was filmed sweeping streets and inaugurating toilets. If you change nothing, nothing will change. A Bollywood movie was even made about a woman who doesnít want to marry her fiancÈ if he doesnít have home latrines. Amitabh Bachan, the Alain Delon of Mombai, became the face of toilets. Itís about converting a nation to defecating in a hole. And five years later, on 2 October 2019, on Gandhiís 150th birthday, Narendra Modi once again addressed his people and the world.
He announced that no one defecated outside anymore. The United Nations, the NGOs, Bill Gates, everyone pretended to believe that, so as not to upset the worldís biggest democracy. In India, the promise and the delivery are not the same. Today, out of the 110 million toilets, it is anybodyís guess whether it is 50 million, or 30 million or 80 million, we do not know.
I think the only thing we can know is that the World Bank has promised to distribute 2 billion dollars to India if they can prove that the toilets has been used. And today I think they still havenít distributed the 2 billion dollar reward. To serve his own political agenda, Narendra Modi chose to massively subsidize latrines, which often went unused. To this day in India, people are still defecating by the side of the road. So we embarked on this adventure with the Gates Foundation to discover the code of bad odors, to understand how to provide a scientific solution for first-time toilet users in India, China, and elsewhere. So, we did some science together. The adventure lasted several years.
For months, Firmenichís researchers travelled to collect fecal odors at the source, in latrines in India, Kenya, Uganda, and South Africa. From this fetid round-the-world trip, they brought back the conviction that, beyond climatic and food specificities, there was a combination of five compounds which, cleverly balanced, could reproduce the exact odor of excrement. Yes, this precious nose which generally designs the essences of our luxury perfumes has been assigned to the effluvia of feces. Taste and smell are tied to emotions. So, could we bring positive emotions to the poorest among us who lack access to toilets? The technique produced a powder to throw in the bowl, a spray, and a hanging air-freshener, and is already sold in several African and Asian countries.
It was tested in India, in the city of Pune, where a start-up is developing a new toilet-bus model exclusively for women. Thatís a fundamental aspect revealed by this toilet revolution: Lack of access to sanitation has a much greater impact on women than on men. And BÈrangËre Magarinos-Ruchat, in a world mostly made up of male engineers and technicians, is an activist for this cause. The lack of access to toilets and hygiene for women is definitely the central issue in this conversation.
For some women, it might mean either getting up very early, before the rest of the family, to go and relieve themselves in the field next to their house or their village, or waiting to go late at night. That's dangerous. We know it has led and still leads to sexual violence, but also to feminine-hygiene problems, infections.
That's why solutions like the buses are really great, because there are diaper stations, information about AIDS, information about how to use feminine hygiene products, assistance and support for women in their personal hygiene. You get none of that out in a field. Nor can you wash your hands, and, as we have all learned in recent months, that can create major health problems. Durban, a South African city with 4 million inhabitants, by the Indian Ocean, is playing a crucial role in the ongoing toilet revolution. Because of the endemic drought in South Africa, but also, more surprisingly, because of the end of apartheid.
My challenge was to prepare for the new South Africa. And, as you know, in apartheid, you had a central city which was mainly white people, surrounded by a sea of poverty, which was mainly African people, many of whom had no services. From 1996 until 2000, it was easy to motivate for money for water, because that was the big issue.
But we started to realize that just bringing water to families was causing another problem, a public health problem. Because then it was creating sewage and the sewage was just running through the houses and causing problems. And then in 2002, we had a cholera outbreak, and that changed everything. Suddenly the politicians said: We need sanitation. With Neil McLeod at the helm, the municipality of Durban has become a pioneer in the separation of urine and fecal matter, to save water.
Itís also testing alternative solutions to the Western flush toilet and water-borne sewage system. A research group at the University of Kwazulu-Natal is Neil McLeodís experimental branch. Naturally, one day, Bill Gates came across Neil McLeod, his pollution-research group, and the crazy sanitation history of Durban.
Then we got that phone call in December 2009. Please be at the Hilton at 6am, in the morning, there's somebody coming to see you, and you can't tell anybody. I thought it was going to be Bill Gates's father and out walked Bill Gates: Hello Neil, what do you want to show me? Why you keep talking to my staff that theyíre in the wrong sector.
And I said, well, you know, my answer to him was: I don't need your money. I need your influence. And we took him out. Chris Buckley came with me, and we showed him what we were doing and how our partnership was evolving. And he went back and he started investing in sanitation and the rest is history. He started the Reinvent the Toilet challenge, and we became the engineering field test center here for all the work.
And that's continued on as we've made all the advances. So, when the Reinvent the Toilet competition was launched by the Bill and Melinda Gates Foundation, Durban and its hundreds of shantytowns were chosen to test the competing toilets designed by Chinese, American, and Swiss universities. There were technical challenges, but there were sociological ones, too.
Among the 10 systems tested in the shantytowns of Durban, a Chinese company had a spectacular failure. In China, you donít throw the toilet paper in the bowl. In South Africa, you do.
Very quickly, their brand-new system broke down in Durban, and it took days to get it back in service. We had a lot of sludge build up. So those were things that we had to deal with on the ground and figure out how to solve. And ultimately, it sort of came to the realization that the way that the process was designed just wasn't applicable to South Africa.
That is one of the challenges when bringing in a system from another country, and bringing it into a developing country, where the municipalities generally do not have the skills or the capacity to maintain and operate these systems. So yeah, there's something that has to be looked at, when you're bringing in a new technology: Are you able to maintain it? Are you able to operate it? Do you have the necessary manpower to do it? Hello, Iím Bill Gates, chairman of Microsoft. In this video, you are going to see the future. Bill Gates has a major technological bent.
You canít really reproach him for that. Itís that bent which has made him one of the richest men in the world from selling computer operating systems to most of us. When he decided to reinvent the toilet so that it could be used even in countries without water-borne sewer systems, Bill Gatesís geeky side naturally came out.
The universities which work for him are developing chemical solutions, reactors to destroy the bacteria in fecal matter, electrolysis-based treatment walls. Their toilets end up looking like spaceships. The injected air pushes the fecal matter into the reactor. The valve closes, and the reaction occurs. It's combustion. The fecal matter is then heated to between 400 and 600∞C, at about 300 bars of pressure.
I think originally, Bill Gates was thinking in this way. He told us when he was young, a computer filled up several rooms to be able only to compute a little bit of information. Today the computing power on our cellphone is able to do the job of very, very big IBM computers long ago.
Therefore, his belief is when technology can be introduced, then everything becomes smaller and smaller. The only difference between the computer and the sh*t is that the computer is in bytes, and you can just keep on growing the bytes without growing the size. Whereas the poop is in atoms, you cannot digitize sh*t. You will always physically have that 200g of sh*t every time. Well, I brought a little exhibit here, this is a container of human feces.
Iím famous that once in a speech I released mosquitoes. This weíre going to keep in the jar. But you know, I think, even though itís very stark, itís good to be reminded that inside there could be over 200 million rotavirus particles, 20 billion shigella bacteria and 100,000 parasitic worm eggs, of which you got a little animation... In November 2018, when Bill Gates placed a jar full of fecal matter on the podium at his conference at the Reinvented Toilet Expo in Beijing, the billionaire proved that heís a master of communications. He achieved the unthinkable: Putting toilets on the global agenda.
He also successfully imposed a new narrative: That excrement can be profitable if itís at the heart of new industries which produce energy and fertilizers. The Toilet Board Coalition was built on the dream of being able to transform poor peopleís poop into money. One of the main ideas behind the Toilet Board Coalition is that the collection of fecal matter in poor countries will be enough to create sufficient energy, like biogas or electricity, to finance the whole sanitation system. In Beijing, everything seemed to be going great.
The universities were proudly presenting their new toilet solutions, and Bill Gates announced that the technologies that his foundation had financed were ready to be adopted by the market. Our goal is to create a multi-billion dollars business opportunity that at some point is getting by without any sort of philanthropic grant money, that it really just evolves into companies competing to buy the best product using these new paradigm. Three years later, in a world in which weíre questioning our development models, priorities have changed. The hyper-technological solutions advocated by Bill Gates are having a hard time finding a foothold in the real world.
Theyíre probably too costly, and they donít challenge our waste management. It was an afternoon like any other at the home of biologist Philippe Morier-Genoud in a village in the Swiss Alpine foothills. There heís testing experimental toilet models which use nature, particularly earthworms, for fecal-matter treatment solutions. We've completely lost touch with the sight and the proximity of our excrement. We excrete, we flush, and it all disappears. It's gone. We don't what happens to it. There are no risks, no odors.
When you see a field big enough to feed a cow throughout the year, there's 500 kg of meat on that cow, and 3 tonnes of earthworms right there under its feet. Itís the earthworms who are hard at work. Worms are bio-reactors. Even their shape reveals that - they're long intestines. Even more so than us, they're guts packed in a thin skin.
They're even better bio-reactors than we are. So much so that this fecal matter, inhabited and colonized by mushrooms and earthworms, becomes edible again for worms. They eat what they excrete, four times or five times. Philippe Morier-Genoud uses earthworms in his home-made toilets to kill bacteria and render the fecal matter harmless. He relieves himself in a tube to give his vegetables the good nutrients contained in his urine. You might think that this Professor Calculus of the restroom, this earthworm fanatic, isnít a very serious person, and that heís not going to solve the global toilet problem.
But then Philippe invited us to follow him to Geneva. This is a building in the heart of the city. Its residents decided to develop a more ecological sanitation system which could reinject wastewater into very low-volume flush toilets. They called Philippe Morier-Genoud, who rounded up his worms. What do you envision? At first, it was just in your house.
Now it's for 100 people, then for for 300. And then? Buildings with 300 people would be pretty good. After that, the next thing, the neighborhood. You could do this in a whole neighborhood.
Look at the lovely earthworms. A nice big bunch of them. Itís a big pool in the buildingís courtyard, full of straw, excrement, and earthworms, a giant filter which makes it possible to treat organic matter and even a lot of chemicals. The earthworms eat, eliminate, and re-ingest everything dangerous, purifying it. The compost can then safely be used to fertilize the gardens. It doesnít smell bad.
At most, thereís a slight smell of humus wafting in the pit. There is maintenance, right? If it's in a city, don't you have to take some of it out from time to time? No, everything is transformed. Here we have the decomposition of all the components, of all the sugar polymers into carbon dioxide and water.
And all the residual mineral salts are flushed out with the excess water. When you see this hyper-modern building in central Geneva, its 38 dwellings, its 140 residents, youíd never imagine that there are millions of worms on clean-up duty in the courtyard. Our goal is to get water that is cleaner than what comes out of the treatment plant - at least as clean, but cleaner, if possible.
That's not hard to achieve, because water from treatment plants isn't very clean. It's decanted and rapidly digested through injecting oxygen, which helps develop bacteria that consume residual sugars. That's all easy to digest. We're at the first stage of wastewater treatment. This involves removing the large waste arriving from the sewers. We find tree branches, sanitary wipes, all kinds of waste.
It's vital that we remove that from the water before treating it. At first, you focus on the pee-poop side of this story. But then you realize that itís about something else entirely.
This sanitation revolution challenges our entire waste-management system. Because all sorts of things end up in our treatment plants. What is wastewater? It's the water generated by our household activities - toilet water, gray water, from our daily activities. It's also the water used for artisanal and industrial purposes.
Lastly, it's rainwater which washes the air and the city and then flows into the collectors. It's all of that. We're at the activated-sludge treatment stage. It removes nitrogen and phosphorus from the water. How do we do it? Again, we use nature. We cultivate the naturally occurring bacteria in the water.
Of course, in addition to feces, wastewater carries a whole bunch of chemical products called micropollutants, and theyíre much harder to treat. The micropollutants in our sludge - and this is the problem - come from many different sources, ourselves in particular. What you were saying is quite right. When we go about our business, when we're washing our dishes or washing our hair, when we weed our garden, remove moss from our roof, etc.,
those activities lead us, without really realizing it, to use many compounds, many components. Today I get to clean the bathroom bowl. Stuck with the nastiest job in the house? Make it vanish.
Vanish? Total action Vanish. Try it! See, total action Vanish lifts off water stains, disinfects, bleaches... Itís true that, for decades, we were encouraged to throw as many chemicals as possible into our toilet bowls, to eradicate the slightest bacterium.
The problem is that micropollutants are getting worse as humankind invents new compounds, and produces new compounds without having studied the harm they might do to human health and the environment. We're creating an increasingly serious problem. Not only are these synthetic compounds not removed in treatment plants, they also accumulate in places where we really don't want them to. At the outset, this toilet revolution stemmed from the idea that we have to give sanitary facilities to those who donít yet have any. Itís also about giving developing countries small treatment plants to avoid investing colossal sums for water-borne sewage systems and giant treatment plants. Especially in South Africa where we don't have the space, the facilities to put in more big large central wastewater treatment works.
And it makes more sense economically and also environmentally to have on-site sanitation treatment, or decentralized treatment systems, rather than putting an extensive piping to take everything to a central place. It's much better to treat it at source. And if you can take that and produce something useful out of it, that's even better. But the truth is that new toilets, new wastewater-treatment models, also solve our first-world problems.
Decentralization, treatment in each neighborhood or each residence could enable us to better control what we release into nature. And maybe it would make us more responsible. I really believe that with on-site treatment, decentralized treatment we can really improve the overall sanitation system. There will always be a place for centralized systems, definitely.
But not for every location. We also have to rethink the water use. Now we have the water supply and itís such a big achievement that we have fresh water, drinking water supplied by pipes. But do we really need drinking water for toilet flushing? And do we really need 50 liters per person per day for toilet flushing? No, we donít need that. So we can actually recycle water. So in large buildings we can treat the grey water, the water from the bathroom and the kitchen, not the toilet water, we can treat that rather easily to reuse it for toilet flushing. We should do that. We should explore new options.
So, itís not just about the little boysí or little girlsí room. For the last 10 years, this broad rethink of the way in which we manage our most basic waste is a definite point of no return. Around the world, the vast majority of wastewater, more than 80%, goes untreated.
Our stool, our urine contribute to the over-fertilization of the oceans, to excessive algae growth, and to the asphyxiation of the sea floor. The way in which we manage our excrement isnít insignificant. Itís the very heart of life. Fecal matter and urine have always fed the ground which feeds us. When fear of disease in cities led us to banish our waste as far away as possible, we replaced natural fertilizers with chemical fertilizers. When we stopped giving back to the soil what we took out of it, because we started living in cities, and it cost too much to return to the earth things which should return to the earth, we created instability.
We might not all end up with earthworms at home to eat our excrement. But this idea that feces should return to the ground, that we canít content ourselves with getting rid of these substances without transforming them, reintegrating them into the life cycle will certainly be the foundation for the launch of the upcoming toilet revolution.
2022-10-09