India, Aug. 5 -- The central government has reacted to social media discussion and theories that E20 petrol - blended with 20 per cent ethanol - causes a drastic drop in mileage, especially in cars, and causes damage to the fuel tank and engine.

The ministry of petroleum and natural gas issued a statement that such allegations are not backed by science, and that the impact on fuel efficiency, if any, is only marginal.

In a social media post, the ministry said mileage may drop by 1-2 per cent in vehicles that are originally designed for E10 petrol but later calibrated for E20; in other vehicles, the drop could be around 3-6 per cent.

However, better engine tuning and use of E20-compatible parts can cut this drop, it said. E20-compliant ...