The degradation products of phenol were identified with high performance liquid chromatography–mass spectrometry (HPLC–MS) measurements using a chromatographic system equipped with a UV detector set at 300 nm. Chromatographic system was interfaced to a PE SCIEX model API3000 Triple Quadruple mass spectrometer equipped with a turbo ion spray interface. Samples were eluted at 1.5 ml min−1 through an Inertsil ODS 3 V column (5 mm, 150–4.6 mm) with the following gradient: from 0/100 (ammonium acetate 10 mM in acetonitrile/water) to 95/5 in 25 min, which was then maintained for10 min. The interface conditions for the positive ion mode were as follows: nebulizer gas = 8 L min−1, curtain gas = 12 L min−1, needle voltage = 4500 V at 450 ◦C, orifice declustering potential = +10 V and focusing potential = 100 V. The flow from the HPLC-UV was split to allow 200 ml min−1 to enter the turbo ion spray interface.