All trains could soon have bio-toilets, with the Ministry of Rural Development offering to bear half the total cost — Rs. 500 crore — of installing them.

After meeting with Railway Board Chairman Vinay Mittal on Tuesday, Rural development Minister Jairam Ramesh said his Ministry would pay 50 per cent of the cost of retrofitting all 50,000 existing train coaches with green toilets, provided that the Railways pay the rest of the bill.