The International Museum of Toilets in New Delhi. For India'sThe theme of toilets for all will be taking centre stage in New Delhi, when the capital hosts the seventh International Toilet Summit this week
For India's low-cost toilet champion, each new loo means freedom not just from rampant disease, but one more chance to liberate someone from doing the awful job of disposing of someone else's waste.
In the centuries-old caste system, with its ingrained fear of "pollution," the deepest revulsion has traditionally been reserved for those who do India's dirty work, such as taking away human waste from homes in buckets.
"The entire community did a good excellent job for society -- without them people would have died of disease," Bindeshwar Pathak said of India's low-caste community.
"What did society do for them? It made them into 'untouchables.'"
For more than three decades Pathak, who founded the sanitation promotion organisation Sulabh (Convenience), has been promoting toilets that are cheap to build and don't require a sewer connection.
And from Wednesday, the theme of toilets for all will be taking centre stage in New Delhi, when the capital hosts the seventh International Toilet Summit.
Pathak, inspired by freedom icon Mahatma Gandhi, kicked off his lavatory mission after he lived with a community of "night soil scavengers" for a few months in the 1970s, and after a childhood incident.
Pathak, a Brahmin, remembers being severely reprimanded by his grandmother for once touching a low-caste woman in his village in Bihar state.
"She made a hue and cry," said Pathak, smiling as he recounted the event that he remembers as one of the most defining moments in his life. "She made me swallow cow dung, cow urine, sand and Ganges water to purify me."
The organisation he started has since built 1.2 million toilets in India that are used by 10.5 million people a day.
But that's just a drop in the bucket in a country where more than 700 million need proper toilets that dispose of waste without polluting soil or water.
Every year almost 400,000 Indian children die because of diarrhoea, according to Unicef, largely because of contaminated water.
Even in cities, about 100 million people don't have proper toilets, and many of these still rely on people to carry their feces away in buckets or to periodically unclog public drains into which the waste flows.
In capital New Delhi, official figures say a fifth of its 14 million residents are not connected to a sewage system. Some estimates say the figure is half.
Those in rural areas use their fields or, in what is a common sight for train travellers, head to railway tracks.
And women head in the early morning or night to hidden spots, leaving them vulnerable to sexual assault, development workers say.
The conference, with participants from 40 countries, will discuss how to remedy the lot of the 2.6 billion people globally who need sanitation, a number the UN hopes to halve by 2015 as part of its Millenium Development Goals.
But Pathak says western toilets based on sewage pipes and abundant water will never get the job done in the developing world, where more than 99 percent of the loos are needed.
"It is so costly in construction and the water it requires is so enormous. It is totally impossible for them," he said.
"It was designed for a city of three million or six million. In this city eight million have no facilities."
Pathak is promoting another environmentally-friendly toilet system that recycles human waste into biogas without releasing greenhouse gases. The gas can then be piped for electricity or cooking.
"We want others to know about this technology, which was recently installed at Kabul, Afghanistan, because it can help meet the Millennium Development Goals and reduce global warming," he said.
So far, the organisation has built 175 of these toilets, which are being used by 175,000 people.
But Pathak admits the system -- though odourless -- will take a little getting used to, recalling a party of Cambodians who went queasy upon finding out that the food they had eaten at Sulabh's offices was cooked with this gas.
The four-day conference is being jointly organised with the World Toilet Organisation, which was founded in 2001 and aims to make sanitation a key global issue and now says it has 55 member groups from 42 countries.