The degradation of tetraethylene glycol (TEG) was studied at 70 °C under dry air and nitrogen. Degradation products were detected using gas chromatography-mass spectrometry (GC–MS). They were mono-, di- and tri-ethylene glycol, mono- and di-formates of mono-, di-, tri- and tetra-ethylene glycol and formic acid. The rate of TEG degradation was significantly decreased by approximately 10 mmol/l KI, FeCl 3 , Cu(CH 3 COO) 2 , MnO 2 and CuSO 4 , small amounts of fresh oak wood sawdust and gypsum-containing scrapings from the wood surface of the Vasa ship in Stockholm. Thus certain salts and natural components of archaeological wood are able to inhibit oxidative degradation of TEG. NaFe 3 (SO 4 ) 2 (OH) 6 (Natrojarosite), FeS 2 (pyrite), FeSO 4 , Fe 2 (SO 4 ) 3 , NiCl 2 , NiSO 4 , Fe, Cu, Fe 2 O 3 , CuO, NaHSO 4 and natrojarosite-containing scrapings from the Vasa had no major effect on the rate of oxidation.