India’s nationwide rollout of E20 petrol, a 20% ethanol blend, has sparked controversy as internal emails show major carmakers warning of chloride and moisture contamination damaging vehicles, even while publicly backing the policy. SIAM’s withdrawn complaint, based on tests from 250 samples across 21 regions, highlighted widespread breaches of government limits, raising questions over fuel quality, transparency and regulatory oversight.
IN 2025, THE INDIAN GOVERNMENT launched the E20 petrol — a fuel blend containing 20% ethanol — on a nationwide basis. When consumers started complaining about vehicle damage and reduced mileage amongst other concerns, the government provided multiple reassurances, vouching for the ethanol-blended petrol’s safety. Hours after India publicly assured that ethanol-blended petrol was safe, the country’s leading automobile industry body withdrew a complaint it had submitted to the government a week earlier over concerns about fuel contamination. The group said some of the figures cited in the complaint required further verification.
Despite government reassurances about the E20 petrol’s safety for vehicles, India top carmaking companies — including Tata Motors, Maruti, and Mahindra — have expressed their concerns over the contamination of petrol blended with 20% ethanol. Communication emails between company executives, as compiled and reviewed by Reuters, revealed that carmakers were privately worried about several contaminants in E20, like chloride and moisture, which they say are damaging vehicles, even as they publicly backed the government's rollout of the ethanol-blended fuel.
The Modi-led Indian government launched the E20 petrol on a nationwide scale in 2025, in a bid to reduce pollution and cut oil imports. Since April 1, 2026, the E20 petrol variety is the only available option sold at filling pumps, leaving consumers no other choice.
In a letter dated July 28, 2026, The Society of Indian Automobile Manufacturers (SIAM) expressed concerns about fuel contamination in the E20 variety and the damage it would do to vehicles. As public uproar ensued, SIAM subsequently withdrew its letter, citing that “some numbers need authentication.”
Industry data and emails reviewed by Reuters, which had not been previously reported, indicate that multiple automakers had already carried out extensive testing of the E20 petrol, collecting more than 250 fuel samples from petrol pumps over a year across as many as 21 of India’s 36 states and union territories. The tests found elevated chloride contamination in many samples from 18 states, along with high levels of moisture.
In a statement given to Reuters, SIAM maintained that the emails and communication acquired by the news agency were meant only for internal discussion, circulation, and validation, and were collected by “very few” automakers.
SIAM further stated that the internal email was sent 'inadvertently,' adding that the 'testing basis and sample size were insufficient to support definitive conclusions." The automobile lobby added that it intends to conduct a proper scientific study for conclusive results.
While the Ministry of Petroleum and Natural Gas declined to give a direct statement to Reuters on this matter, Minister Hardeep Puri, on Friday, August 7, 2026, stated that two weeks before receiving SIAM’s letter, India's oil marketing companies had begun “rigorous testing” of fuel at retail outlets to check for contamination. Puri said that only four cases of fuel contamination were noted.
Additionally, in a statement published on the Press Information Bureau’s website on August 8, 2026, the Petroleum Ministry stated that Oil Marketing Companies (OMCs) tested E20 petrol for the presence of moisture and chloride, and added that “claims of 500 ppm chloride and presence of moisture are not validated.”
Mahindra said that conclusions based on its executive’s emails were “completely baseless and incorrect,” adding that the industry data was limited and preliminary and that it had found no issues with E20 fuel.
In group emails circulating between Maruti, Mahindra, and Tata Motors, Maruti’s Senior Executive Anoop Bhut flagged concerns about the elevated presence of chloride in the E20 variety, and stated these concerns were discussed with the government on July 26, 2026.
SIAM had previously stated that elevated chloride levels can cause corrosion in automobile components, while excessive moisture in fuel can lead to a vehicle becoming immobilized soon after refuelling. State-wise data shared by the industry through group emails showed chloride levels ranging from 6 to 570 parts per million (ppm) in Rajasthan, 1.4 to 420 ppm in New Delhi, and 10 to 357 ppm in Maharashtra. The Indian government’s permissible limit is 3 ppm.
The same data showed moisture levels as high as 13,000 ppm in Andhra Pradesh and 12,500 ppm in Uttar Pradesh, compared with the government’s permissible limit of 3,000 ppm.
Although the exact cause of the contamination remains unclear, SIAM said in its now-withdrawn letter that chloride levels had increased since the introduction of E20 fuel. It urged the government to ask oil marketing companies to identify the root cause. On moisture contamination, SIAM said inadequate maintenance of underground storage tanks and pipelines at fuel stations could be responsible.
(Edited by Agniva Ray)
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