Formation of oxidation by-products of the iodinated X-ray contrast medium iomeprol during ozonation.
The present work describes the investigation of the formation of oxidation by-products of the iodinated X-ray contrast medium (ICM) iomeprol during ozonation in water treatment. Bench-scale investigations revealed that ICM can be partly oxidized during ozonation processes, whereas the ionic diatrizoic acid showed the lowest reactivity. Iomeprol, as a representative of ICM, was not fully mineralized during ozonation. Thus, unknown oxidation by-products were formed. Aqueous solutions of iomeprol were treated by ozonation in order to assess the formation of oxidation by-products. The by-products were characterized by different liquid chromatography methods including detection of single-stage mass spectra, product ion mass spectra, and induced in-source fragmentation for analysis of iodine containing oxidation by-products. Aldehyde and carbonyl containing compounds were proposed to be among the stable by-products. A derivatization step confirms that the aldehyde and carbonyl moieties are major functional groups in oxidation by-products of iomeprol. Furthermore, oxidation by-products of iomeprol were detected at the outlet of an ozone reactor at a full-scale waterworks. However, the toxicological relevance of the by-products is a major future research tasks.
Seitz
Wolfram
W
Zweckverband Landeswasserversorgung, Betriebs- und Forschungslaboratorium, Am Spitzigen Berg 1, D-89129 Langenau, Germany.
Jiang
Jia-Qian
JQ
Schulz
Wolfgang
W
Weber
Walter H
WH
Maier
Dietrich
D
Maier
Matthias
M
D002853:Chromatography, Liquid; D003287:Contrast Media / Q000737:chemistry*; D007455:Iodine / Q000737:chemistry; D007479:Iopamidol / Q000031:analogs & derivatives* / Q000737:chemistry; D015394:Molecular Structure; D010084:Oxidation-Reduction; D010126:Ozone / Q000737:chemistry*; D053719:Tandem Mass Spectrometry
D003287:Contrast Media; C057937:iomeprol; D010126:Ozone; D007455:Iodine; D007479:Iopamidol