Only about 10% of the gadolinium released into the waste water resulting from its use as MRI contrast agent is removed from the waste water stream. This is the result of a new study done by researchers from the University in Muenster (Germany).
Background:Magnetic resonance imaging (MRI) is an indispensible method for clinical diagnostic used for imaging inner organs. Almost every second MRI examination worldwide is enhanced by application of a Gd-based contrast agent. The MRI agents are excreted quantitatively from the patient’s body unmetabolized and fast via the urine. Depending on the number and activity of clinical centers performing MRI examinations within the catchment area of a sewage treatment plant, the input of Gd into the public sewer is therefore relatively high. Since these agents are very stable compounds, their degradation during wastewater treatment is a critical issue.
The new study:
Figure: the structure of the prominent
Gd MRI contrast agent found in Muenster
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The total concentration of Gd in influent and effluent 2h- and 24h-composite samples was determined by means of isotope dilution analysis. The balancing of Gd input and output of the sewage plant of the city of Muenster (Germany) over a week indicated that only approximately 10% of the Gd is removed during treatment. Using the hyphenated technique HPLC-ICP-MS for Gd speciation analysis, the
researchers of the University of Muenster were able to separate the most often used Gd-based MRI agents and quantify them in the wastewater stream. Using this technique, it could be shown that the main compound entering the plant was Gd-BT-DO3A (about 80%). While the 10% of gadolinium removed from the waste water could not be found within the sewage sludge, the effluent from the chamber filter press, dewatering the sludge, showed the presence of three unknown Gd species not observed before. This seems to be an indication of species transformation during anaerobic sludge treatment. The low removal capacity of biological wastewater treatment for Gd-based MRI contrast agents is consistent with the high values of anthropogenic Gd in surface waters that was found all over the world.
The original study
Lena Telgmann, Christoph Alexander Wehe, Marvin Birka, Jens Künnemeyer, Sascha Nowak,
Michael Sperling, and
Uwe Karst,
Speciation and Isotope Dilution Analysis of Gadolinium-Based Contrast Agents in Wastewater, Environ. Sci. Technol., 46/21 (2012) 11929-11936.
doi: 10.1021/es301981z Homepage of the research group of Prof. Karst at the Institute of Inorganic and Analytical Chemistry of the University of Muenster (Germany) Related studies P.L. Verplanck, E.T. Furlong, J.L. Gray, P.J. Phillips, R.E. Wolf, K. Esposito,
Evaluating the Behavior of Gadolinium and Other Rare Earth Elements through Large Metropolitan Sewage Treatment Plants, Environ. Sci. Technol., 44 (2010) 3876-3882.
doi: 10.1021/es903888t M.G. Lawrence, J. Keller, Y. Poussade,
Removal of magnetic resonance imaging contrast agents through advanced water treatment plants, Water Sci. Technol., 31 (2010) 685-692.
doi: 10.2166/wst.2010.885.
J. Künnemeyer, L. Terborg,
B. Meermann, C. Brauckmann, I. Möller, A. Scheffer,
U. Karst,
Speciation Analysis of Gadolinium Chelates in Hospital Effluents and Wastewater Treatment Plant Sewage by a Novel HILIC/ICP-MS Method, Environ. Sci. Technol., 43 (2009) 2884-2890.
doi: 10.1021/es803278n M.G. Lawrence, C. Ort, J. Keller,
Detection of anthropogenic gadolinium in treated wastewater in South East Queensland, Australia, Wat. Res., 43 (2009) 3534-3540.
doi: 10.1016/j.watres.2009.04.033 M. Bau, A. Knappe, P. Dulski,
Anthropogenic gadolinium as a micropollutant in river waters in Pennsylvania, and in Lake Erie, northeastern United States, Geochem., 66 ( 2006) 143-152.
doi: 10.1016/j.chemer.2006.01.002 Y. Zhu, M. Hoshino, H. Yamada, A. Itoh, H. Haraguchi,
Gadolinium anomaly in the distributions of rare earth elements observed for coastal seawater and river waters around Nagoya City, Bull. Chem. Soc. Jpn., 77 (2004) 1835-1842.
doi: 10.1246/bcsj.77.1835 K. Kümmerer, E. Helmers,
Hospital effluents as a source of gadolinium in the aquatic environment, Environ. Sci. Technol. 2000, 34, 573-577.
doi: 10.1021/es990633h M. Bau, P. Dulski,
Anthropogenic origin of positive gadolinium anomalies in river waters, Earth Planet. Sci. Lett., 143 (1996) 245-255.
doi: 10.1016/0012-821X(96)00127-6
Related EVISA Resources
Brief summary: ICP-MS - A versatile detection system for speciation analysis Brief summary: LC-ICP-MS - The most often used hyphenated system for speciation analysis Brief summary: Speciation analysis for the study of metallodrugs and their biomolecular interactions Link database: Use of Gadolinium in pharmaceuticals
Related EVISA News (newest first)
October 29, 2012: Identification and quantification of potential metabolites of Gd-based contrast agents October 18, 2012: The behavior of Gd-based contrast agents during wastewater treatment September 15, 2010: US FDA Announces Gadolinium-Based MRI Contrast Agent Warninglast time modified: May 17, 2024
