A high-stakes dispute has erupted between the Karnataka state government and India’s premier state-run oil refiners over the quality and composition of retail motor fuel. The controversy began after the Karnataka Department of Food, Civil Supplies, Consumer Affairs and Legal Metrology alleged that petrol dispensed at several retail fuel stations across seven districts contained ethanol levels ranging between 26% and 31.2%—far in excess of the nationally mandated 20% (E20) blending ceiling. In a joint response issued from Bengaluru, the three major public sector Oil Marketing Companies (OMCs)—Indian Oil Corporation Limited (IOCL), Bharat Petroleum Corporation Limited (BPCL), and Hindustan Petroleum Corporation Limited (HPCL)—strongly rejected the state’s allegations. The refiners stated that the findings were derived from improper, unilateral sampling that bypassed statutory testing procedures, reaffirming that all commercial gasoline supplied across Karnataka strictly conforms to national quality standards established by the Bureau of Indian Standards (BIS).

The Accusation: Karnataka Alleges Over-Blending and Vehicle Damage

The confrontation unfolded following a press conference convened by Karnataka Food, Civil Supplies, Consumer Affairs and Legal Metrology Minister Rizwan Arshad. Addressing the media, the minister revealed that state inspectors had collected 63 fuel samples from retail fuel pumps across seven key districts: Bengaluru Urban, Bengaluru Rural, Kolar, Chikkaballapura, Ramanagara, Tumakuru, and the coastal hub of Mangaluru. According to Arshad, laboratory tests initiated by the state indicated that four out of every five pumps inspected were dispensing fuel with ethanol concentrations significantly higher than the statutory 20% limit, with several locations registering blending rates as high as 31.2%.

Framing the issue as a critical matter of consumer rights and vehicular safety, the Karnataka minister contended that excessive ethanol blending risks severe mechanical damage to automobile engines. Ethanol possesses hygroscopic properties, meaning it readily absorbs atmospheric water, which can accelerate the corrosion of fuel tanks, rubber fuel lines, gaskets, and fuel injectors in engines not explicitly calibrated for high-ethanol blends. Arshad claimed that because the vast majority of two-wheelers and passenger cars currently operating on Indian roads are compliant only with E10 or older specifications, unauthorized blending places an unfair financial burden on vehicle owners. The state government alleged that nationwide over-blending leads to substantial mileage drops and heightened maintenance expenses, demanding that the Union Government take punitive action against the OMCs and establish a consumer relief fund to compensate affected motorists.

Procedural Lapses: OMCs Question Unilateral Testing and Third-Party Labs

Rejecting the state’s claims, IOCL, BPCL, and HPCL issued a detailed joint statement disputing both the reported numbers and the technical methodology used by the state department. The refiners emphasized that fuel testing in India is governed by strict statutory protocols under the Motor Spirit and High Speed Diesel (Regulation of Supply, Distribution and Prevention of Malpractices) Control Order, as well as the Marketing Discipline Guidelines (MDG 2024). Under these legal guidelines, fuel sampling cannot be conducted arbitrarily; it mandates joint sample collection witnessed and signed by both state authorities and authorized representatives of the oil company or retail outlet dealer.

The OMCs pointed out that while fuel samples collected during an earlier exercise in September 2026 were routed through established channels to designated testing facilities, the state’s October inspection drive was conducted unilaterally, without the presence or endorsement of OMC personnel. Crucially, the oil companies highlighted that the state government failed to provide counterpart retention samples, outlet-wise verification logs, or formal test methodologies to the affected companies. The refiners noted that the state's alarming numbers relied on test certificates issued by an external third-party laboratory rather than an accredited referee laboratory recognized under the Control Order. This procedural breach, the OMCs argued, denied dealers and refiners the basic legal safeguard of independent retesting, casting serious doubt on the scientific validity of the findings.

Strict Adherence to BIS IS 17021: National Blending Data

Refuting allegations of lax quality oversight, the oil companies presented empirical testing data to demonstrate that retail fuel distribution remains tightly regulated. The OMCs revealed that across 27 States and Union Territories, a total of 893 retail E20 fuel samples had undergone comprehensive laboratory analysis. Significantly, all 56 retail samples drawn specifically within the state of Karnataka conformed fully to the Bureau of Indian Standards specification BIS IS 17021, which governs ethanol-blended motor gasoline. Laboratory logs showed that ethanol content across Karnataka fuel stations consistently registered between 19% and 20%, recording an overall state average of 19.30%—solidly within the prescribed legal parameters.

The refiners also placed macro-level supply figures on record to demonstrate that large-scale excess blending is mathematically and logistically impossible. During the 2025–26 ethanol supply year, which concluded on October 31, 2026, the three public sector OMCs procured 1,089 crore litres of ethanol from domestic distilleries. Over the same twelve-month cycle, the companies blended 1,134 crore litres of ethanol against total domestic petrol sales of roughly 5,673 crore litres. These figures confirm that nationwide ethanol blending sits uniformly at the 20% target, leaving no unaccounted surplus that could facilitate regional concentrations reaching 31%.

Economic Realities: Why Over-Blending Defies Commercial Logic

Beyond technical protocols, the oil marketing companies dismantled the assumption that refiners possess any commercial incentive to dilute petrol with excess ethanol. In mainstream retail fuel discourse, consumers often assume that blending biofuels represents a cost-cutting tactic by oil firms. However, under India's current pricing framework for biofuels, ethanol produced from sugarcane juice, B-heavy molasses, and surplus food grains is procured at government-fixed incentive rates to support domestic agriculture.

Consequently, the procurement price of fuel-grade anhydrous ethanol per litre is often higher than or comparable to the refinery gate cost of untaxed base motor gasoline. Blending ethanol beyond the statutory 20% limit would directly inflate production expenditures and erode refiners' profit margins. The OMCs pointed out that deliberately supplying 31% ethanol would result in substantial commercial losses for public sector undertakings, making the state's allegations economically counter-intuitive.

Demand for Transparent Referee Testing and Consumer Assurance

To resolve the public anxiety generated by the controversy, the OMCs have formally requested the Karnataka government to share complete documentation, outlet-specific laboratory dossiers, and custody chain records for the 63 disputed samples. The refiners have requested immediate access to the counterpart sealed samples to facilitate independent testing at an authorized referee laboratory using standardized chemical displacement or gas chromatography techniques, carried out in the joint presence of state officials, retail dealers, and OMC technical teams.

The companies reiterated their commitment to participating in transparent, jointly verifiable testing in strict accordance with the Marketing Discipline Guidelines. They affirmed that if any retail dealer is legitimately found tampering with fuel quality or deviating from BIS benchmarks through prescribed testing methods, strict punitive measures—ranging from heavy fiscal penalties to immediate termination of retail dealership licenses—would be enforced under existing fuel control orders.

As India advances its National Biofuel Policy to curb crude oil imports, reduce greenhouse gas emissions, and save foreign exchange reserves, maintaining public confidence in retail fuel quality is paramount. The standoff in Karnataka highlights the need for seamless coordination between state consumer departments and central energy public sector enterprises. By calling for standardized, joint testing protocols, the oil companies aim to dispel misinformation, protect consumer interests, and ensure that India's green energy transition remains anchored in scientific rigor and institutional transparency.