Petrol sold at fuel stations across Karnataka contains far more ethanol than the 20 per cent blend the Union government has mandated, the state government said on Friday, releasing laboratory results that recorded concentrations as high as 31.2 per cent.
The findings have set off a fresh political row over the national ethanol blending programme, with the Congress government in the state demanding action against oil companies and compensation for motorists, and the public sector oil marketing companies firmly rejecting the test results.
Karnataka's Minister for Food, Civil Supplies, Consumer Affairs and Legal Metrology, Rizwan Arshad, announced the results at a press conference in Bengaluru on 6 November.
He said the Department of Legal Metrology had collected 63 petrol samples from fuel stations in seven districts — Bengaluru, Kolar, Chikkaballapura, Bengaluru Rural, Ramanagara, Mangaluru and Tumakuru — and had them tested at the Shriram Research Institute in Bengaluru, a laboratory accredited by the National Accreditation Board for Testing and Calibration Laboratories and certified under international quality standards.
According to the laboratory certificates attached to the state government's statement, ethanol was found above the permitted 20 per cent level in 11 of the 14 samples reported in detail. The highest concentration, 31.2 per cent, was recorded in a sample drawn from an Indian Oil Corporation Limited outlet.
A sample of Hindustan Petroleum Corporation Limited's Power petrol recorded 30.5 per cent, regular HPCL petrol recorded 27 per cent, Bharat Petroleum Corporation Limited's Speed petrol recorded 26.5 per cent, Nayara Energy recorded 26.1 per cent and Shell recorded 25.5 per cent. The outlets sampled represented all the major fuel retailers operating in the state, including Indian Oil, HPCL, BPCL, Nayara Energy, Shell and Mangalore Refinery and Petrochemicals.
Arshad said the state government had initially trusted the Union government's assurance that petrol sold to consumers contained the mandated E20 blend and would not cause problems for vehicles. The test results, he said, showed that trust had been misplaced.
He argued that motorists were paying for petrol while receiving a fuel with a much higher share of ethanol, and that the excess blending was damaging vehicles, reducing mileage and pushing up repair bills for ordinary consumers.
The Legal Metrology Department put a number on that burden. It estimated that excess ethanol blending was costing consumers around 62,000 crore rupees a year through reduced mileage, and a further 39,000 crore rupees a year in vehicle repair costs, taking the total annual burden to nearly 1.01 lakh crore rupees.
The department's case is that ethanol carries less energy than petrol, so a higher ethanol share means a vehicle travels fewer kilometres on every litre, while older engines and fuel system components not designed for high ethanol blends wear out faster.
Arshad made four demands of the central government. First, he sought action against all oil marketing companies found supplying petrol with more than 20 per cent ethanol. Second, he demanded an E20 spoilage fund to compensate motorists for eligible vehicle component failures caused by excess blending.
Third, he called for a nationwide rule requiring every fuel pump to display the exact ethanol percentage at the dispensing nozzle, so that consumers know what they are buying. Fourth, he asked the Centre to state publicly the actual ethanol blend being supplied to consumers across the country. He said the state would submit its findings to the Centre, continue testing petrol, and keep releasing the results.
He also sought explanations from Union Minister for Road Transport and Highways Nitin Gadkari and Union Minister for Petroleum and Natural Gas Hardeep Singh Puri.
The minister also questioned the testing process itself. He said the samples had first been sent to the in-house laboratories of Indian Oil and Bharat Petroleum, but the reports they returned did not disclose the ethanol content even though it is one of the prescribed testing parameters. The department then had the same samples tested at independent accredited laboratories, which produced the higher readings.
The state government has cited the Motor Spirit and High Speed Diesel (Regulation of Supply and Distribution and Prevention of Malpractices) Order, 2005, as the legal basis for action against malpractices in fuel supply and distribution.
The oil companies have pushed back strongly. Indian Oil, Bharat Petroleum and Hindustan Petroleum jointly disputed the Karnataka government's findings, saying the claims were not supported by testing conducted according to the prescribed statutory and technical procedures.
They questioned the sampling and testing methods adopted by the state government and have asked for the complete sampling records, the laboratory reports and access to the retained samples before any conclusions are drawn. Until that material is shared and examined, the companies maintain, the reported 31.2 per cent figure remains a state government testing claim rather than an established fact.
The dispute sits on top of a much larger national argument about ethanol-blended petrol. Under the E20 programme, the Union government has moved the country to petrol blended with 20 per cent ethanol, arguing that it reduces India's dependence on imported crude oil, cuts the fuel import bill and promotes domestically produced ethanol.
The Centre has repeatedly said that ethanol produced from sugarcane and maize boosts farmers' incomes and supports the rural economy, and it has rejected concerns about E20, maintaining that the fuel is safe for vehicles.
Critics of the programme, including motorists' groups and opposition parties, have argued that the benefits have not reached consumers. They point to lower mileage, higher maintenance costs for older vehicles and the absence of a cheaper, lower-blend alternative at most pumps.
The Karnataka government has now taken that argument further, alleging that the Union government's claim that ethanol blending saves foreign exchange has not translated into benefits for consumers, even as oil marketing companies and automobile manufacturers have reaped record profits.
The Centre, for its part, clarified on 23 July 2026 that no decision had been taken to increase ethanol blending in petrol beyond 20 per cent. That clarification has not settled the argument on the ground, where the question is not what the official blend is supposed to be but what is actually being dispensed at the pump. Karnataka's tests, if they withstand scrutiny, would suggest a gap between the two.
The oil companies' challenge, if it holds, would suggest the state's testing was flawed. Either way, the episode has made the contents of a litre of petrol a matter of public argument in a way it has rarely been before.
What happens next will depend on evidence. The state government has promised more testing and public disclosure of the results. The oil companies want the raw records and the retained samples.
The Union government has been asked to explain the actual blending levels and to enforce the display of ethanol percentages at fuel stations. For the millions of motorists who fill up every day, the practical question is simpler: whether the fuel they buy matches the label on the pump, and whether their vehicles are paying a price that nobody told them about.
(Reporting based on The News Minute, NDTV, The South First and Outlook India.)