Bachchan, the campaign ambassador, and Fadnavis took part in the event, along with volunteers and students, at the state government-run J J Hospital here.
"Fifty cities in Maharashtra will be 'swachh' by October 2 and 7,000 villages in the state are now open-defecation free," Fadnavis said.
On public participation in building toilets, the Chief Minister said, "If we don't involve people in the construction of toilets, it doesn't fulfil the purpose. It becomes a storage space."