Determination of antioxidants and UV-stabilizers in the environment

Abstract: Synthetic antioxidants and UV-stabilizers are additives used in plastic products in order to protect the polymers from degradation caused by oxygen and ultraviolet light. Few studies have been performed about the presence of these compound groups in the environment and there is very sparse data on their distribution in the environment in Sweden. The objective of this study was to investigate the presence of ten common antioxidants and UV-stabilizers and two antioxidant metabolites [2-tert-butyl-4-methoxyphenol (1); 2,6-di-tert-butyl-4-methylphenol (2); 3,5-ditert-butyl-4-hydroxybenzaldehyde (3); 2,6-ditert-butylcyclohexa-2,5-diene-1,4-dione (4); 1,3,5-tris[(4-tert-butyl-3-hydroxy-2,6-dimethylphenyl)-methyl]-1,3,5-triazinane-2,4,6-trione (5); tris(2,4-ditert-butylphenyl) phosphite (6); [3-[3-(3,5-ditert-butyl-4-hydroxyphenyl)propanoyloxy]-2,2-bis[3-(3,5-ditert-butyl-4-hydroxyphenyl)propanoyloxymethyl]-propyl]3-(3,5-ditert-butyl-4-hydroxyphenyl)propanoate (7); octadecyl 3-(3,5-ditert-butyl-4-hydroxyphenyl)propanoate (8); 2-tert-butyl-4-(5-tert-butyl-4-hydroxy-2-methylphenyl)sulfanyl-5-methylphenol (9); bis(2,2,6,6-tetramethylpiperidin-4-yl) decanedioate;2-hydroperoxy-2-methylpropane; octane (10); bis(3,3,5,5-tetramethylpiperidin-4-yl) decanedioate (11) and 4-methylhexyl-3-[3-(benzotriazol-2-yl)-5-tert-butyl-4-hydroxyphenyl]propanoate (12)] in water and snow in Stockholm and its surroundings. A method was developed for the determination in water by solid phase extraction (SPE) in order to extract and concentrate the compounds, followed by analysis by liquid chromatography – electrospray – tandem mass spectrometry (LC-ESI-MS/MS). Three compounds (2, 4, 11) were excluded from the method development since (2) and (11)could not generate a signal on the mass spectrometer whereas (4) could not produce a linear response. Due to the wide range of physicochemical properties of the analytes low recoveries were observed. Sampled water and snow from the Stockholm area was analysed and (3) and (9) were found in two of the water samples whereas (10) was observed in all water samples, below the quantification limit. Due to the lack of time, no methods were developed for the determination of the selected plastic additives in other environmental compartments.