Nila Madhab Panda's directorial "Halkaa", which addresses the problem of poor sanitation in India, has caught the attention of actor Varun Dhawan, who says the absence of sanitation facilities is one of the main reasons for open defecation in India.Varun said in a statement: "There are street kids whose role Tathastu (child artiste) is playing... As people who want toilet facilities and if it's not there, where they will go - on the rail tracks or open. The film holds a strong message, where a young boy aspires to build a toilet."The 31-year-old actor also shared an incident when he had to defecate in the open."I was a six-year-old and was travelling in a bus with my cousins in England. I wanted to go to the toilet, but there was no toilet in the bus. There were lot of parks there and I just ran from the bus towards the park thinking it's a forest and did it... Because I was a kid, they forgave me," added Varun."Halkaa" is a story of an eight-year-old boy Pichku played by Tathastu, who lives in the oldest slums of Delhi and cannot bring himself to go out every day and defecate in the open fields around the slum.The film is slated to release on September 7.