Relationship between gadolinium-based MRI contrast agent consumption and anthropogenic gadolinium in the influent of a wastewater treatment plant

• Published in: The Science of the total environment Vol. 877; p. 162844
• Main Authors: Laczovics, Attila, Csige, István, Szabó, Sándor, Tóth, Albert, Kálmán, Ferenc Krisztián, Tóth, Imre, Fülöp, Zoltán, Berényi, Ervin, Braun, Mihály
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 15.06.2023
• Subjects: Advection-dispersion transport model; Anthropogenic gadolinium; Contrast Media; environment; excretion; Gadolinium; Gadolinium-based contrast agent; Humans; Inductively coupled plasma mass spectrometry; Magnetic Resonance Imaging; magnetism; Metals, Rare Earth; patients; quantitative analysis; sewer systems; urban areas; Wastewater; Wastewater treatment; Gadolinium-based contrast agent; Inductively coupled plasma mass spectrometry; Advection-dispersion transport model; Anthropogenic gadolinium; Wastewater treatment
• ISSN: 0048-9697; 1879-1026; 1879-1026
• DOI: 10.1016/j.scitotenv.2023.162844

Gadolinium-based contrast agents (GBCAs) used in magnetic resonance imaging (MRI) are highly resistant in the environment. They pass through wastewater treatment plants (WWTPs) unhindered escaping degradation. Although GBCAs are subjects of intensive research, we recognized that a quantitative approach to the mass balance of gadolinium, based on known input and output data, is missing. The administered amount of Gd as GBCAs, the number of out- and inpatients and the concentration of rare earth elements (REEs) in wastewater were monitored for 45 days in a medium sized city (ca. 203,000 inhabitants) with two MRI centres. An advection-dispersion type model was established to describe the transport of Gd in the wastewater system. The model calculates with patient locality, excretion kinetics of Gd and the yield of wastewater. The estimated and measured daily amount of anthropogenic gadolinium released to the WWTP were compared. GBCAs (Omniscan and Dotarem) were administered to 1008 patients representing a total of 700 ± 1 g Gd. The amount of total Gd entering the WWTP was 531 ± 2 g, of which the anthropogenic contribution (i.e. GBCAs) was 261 ± 6 g (49 ± 1 % of the total Gd) during the sampling campaign. Local residents and inpatients should fully release Gd in the city, but outpatients only partially. Overall, 37 ± 1 % of the total administered Gd was recovered in the wastewater, so the remaining 63 ± 1 % of administered Gd is expected to be dispensed outside of the sewer system. Our approach enables to better understand the dispersion of GBCAs originated Gd in an urban environment. [Display omitted] •Release of Gd from patients to sewage system was quantitatively described.•Overall, 37 % of the administered Gd was recovered at the WWTP.•Advection-dispersion model was fitted for temporal distribution of Gd in wastewater.•The speed of Gd release from patient to WWTP was slower than expected.