The influence of 1,2-, 1,3- and 1,4-dihydroxybenzene and a-tocopherol on thermal-oxidative decomposition of linolenic acid (LNA) initiated by alpha,alpha'-azoisobutyronitrile (AIBN) was investigated by DSC in scanning mode. The concentration of the phenols varied from 0.5 to 20 mmol of compound per mol LNA. Values of activation energy calculated from temperatures of the start of LNA thermoxidation (by the Ozawa-Flynn-Wall method) were 74.6 +/- 3.4 kJ/mol (initiated but non-inhibited LNA), and for inhibited LNA 93.8 +/- 8.7 kJ/mol for hydroquinone, 106.8 +/- 5.5 kJ/mol for resorcinol and 116.3 +/- 11.0 kJ/mol for pyrocatechol. For a system inhibited by a-tocopherol at 1.94 mmol per mol LNA, the activation energy equals 96.1 +/- 13.3 kJ/ mel. Arrhenius pre-exponential factors and rate constants of oxidation at 90 degrees C are presented.