Speciation Analysis of Gadolinium Chelates in Hospital Effluents and Wastewater Treatment Plant Sewage by a Novel HILIC/ICP-MS Method

Abstract

The behavior of Gd chelates used in magnetic resonance imaging (MRI) within the process of sewage treatment is widely unknown. Due to the varying toxicity of the particular Gd species [J. M. Idee et al. Fundam. Clin. Pharmacol. 2006, 20, 563-576], it is important to not only investigate total Gd concentrations, but the Gd species as well. This work describes a novel method for speciation analysis of the most important gadolinium chelates in wastewaters. This novel approach consists of coupling hydrophilic interaction chromatography (HILIC) with inductively coupled plasma mass spectrometry (ICP-MS). HILIC/ICP-MS exhibits high separation efficiency for the simultaneous separation of the five predominantly applied MRI contrast agents and the required selectivity and sensitivity for trace determination in wastewater samples. For the first time, the distribution of particular Gd chelate complexes was determined in hospital effluent, municipal sewage, and wastewater treatment plant (WWTP) samples. The data were compared with the total concentration of Gd as determined by ICP-MS. The active compounds of Multihance, Dotarem, and Gadovist were identified in local WWTP samples. Interestingly, the macrocyclic, nonionic compound Gd-BT-DO3A (Gadovist) was found to be the most abundant Gd complex in all investigated samples. This is in contrast to prevalent assumptions that linear ionic Gd chelates such as Gd-DTPA (Magnevist) would be the predominant species [G. Morteani et al. Environ. Geochem. Health 2006, 28, 257-264 and M. Bau and P. Dulski, Earth Planet. Sci. Lett. 1996, 143, 245-255]. Although contrast agent concentrations tend to be reduced during wastewater treatment, Gd-BT-DO3A was still found in WWTP effluents.

Intérêt du dosage de quatre éléments minéraux dans les eaux usées pour le suivi des activités médicales

“…Il serait intéressant de connaître la ou les formes sous laquelle ou lesquelles se trouve(nt) le gadolinium, minérale ou/et organique, pour optimiser le traitement complémentaire à mettre en oeuvre au sein de la STEP, afin de procéder à son élimination. Pour ré-pondre à cette question, Künnemeyer et al [15] proposent une technique de spéciation des chélates de gadolinium.…”

Hyphenated techniques as tools for speciation analysis of metal-based pharmaceuticals: developments and applications

“…As can be seen from the list provided in Table 1, applications of SEC tend to be investigations of protein-drug adduct formation [8,9]. The separation of more polar or even ionic species is possible using HILIC [10,11]. The HILIC separation mode is based on the interaction of the species with a zwitterionic stationary phase (electrostatic interaction, hydrophilic partitioning).…”

Effect of Mg and Ca on the Stability of the MRI Contrast Agent Gd–DTPA in Seawater

“…Although the released Gd is highly particle-reactive and should be quickly transferred to the particulate phase, it may eventually be remobilized by diagenetic processes and rejoin any remnant undissociated Gd complexes that are transported away from the estuary. In this regard, the ongoing development of advanced analytical techniques that can identify and quantify individual organic Gd species directly will be particularly beneficial (Künnemeyer et al, 2009a).…”