NEW DELHI - His hands protected by torn orange gloves, Dalbira Singh has a grim job scraping waste from train toilets from the tracks at New Delhi's Hazrat Nizamuddin station, a few minutes from Prime Minister Narendra Modi's office.
Like an estimated 1 million other Indians, Singh does the work because he was born into a low caste. His parents did the same work before him.
"This is a disgusting job but no one will give me another. I am destined to be a toilet-cleaning man," Singh said this week, picking up soiled sanitary towels and diapers before wiping the tracks with a cloth soaked in cleaning chemicals.
But Modi, like Mahatma Gandhi, wants to change things so not only those born to a low caste work to keep India clean.
On Thursday, a holiday for Gandhi's birthday, Modi launched the Swachh Bharat Abhiyan, or Clean India Mission, to modernise sanitation within five years.
He starting by trying to change attitudes and he set an example by taking a broom and sweeping up rubbish in a Delhi neighbourhood occupied by members of the Valmiki caste, whose lot in life is traditionally "manual scavenging", a euphemism for clearing other people's faeces.
"Often we assume the job of cleaning up belongs to safai karmacharis and don't bother to clean," Modi said referring to cleaners.
"Don't we all of have a duty to clean the country?"
To drive home his point, he ordered government workers including his ministers came to work on Thursday to sweep offices and clean toilets.
India's fast-growing towns and cities are littered with rubbish. Most rivers and lakes are polluted with sewage and industrial effluents.