The chemical content at the leak site on the M7 highway is not fixed. Its absence in the air was established by the specialists of the Central Specialized Inspectorate for Analytical Control of the Ministry of Ecology of the Republic of Tatarstan, having carried out an analysis on a chromato-mass spectrometer. Additionally, air quality was evaluated by 41 indicators: 15 components were checked on site, 26 in the laboratory. Exceedings of maximum permissible concentrations were not detected.