Of the 30 samples of loose and packed oil taken from various shops and oil mills in the City, three tested positive for the presence of Argemone oil. Two of these samples are manufactured by Khandelia Oil Mills and Ganesh Oil Mills in Industrial Area (Phase II), according to sources.

The third sample, of loose variety, was recovered from an oil manufacturer in Manimajra. The samples subjected to the "nitric acid test" on Saturday had tested negative for Argemone oil, before the chromatography test.

Dr R.S. Sandhu, director, UT Health Services, issued the orders to ban these brands soon after test reports by public analyst Suresh Kumar Kalra confirmed adulteration. "While a few samples have been found to be positive for Argemone oil, no deaths have been reported so far due to mustard oil adulteration," Dr Sandhu told Newsline. The concentration of the Argemone oil must be in less concentration, he added.