MRI Contrasting Agents Containing REE Gadolinium are Contaminating North and Baltic Seas

 

     Water testing shows that magnetic resonance imaging (MRI) contrasting agents are accumulating in the North and Baltic Seas, coming from rivers after being excreted by patients. CritMET research group, led by Prof. Michael Bau, a geochemist at Constructor University in Bremen, did the study. Modern wastewater treatment plants do not remove these substances. The main substance of concern is the rare earth element gadolinium. It is unclear how this gadolinium is affecting aquatic organisms or how it breaks down over time. Aquatic organisms such as fish and mussels are being analyzed for effects from the substance. There is also concern that the chemicals could reach groundwater and drinking water supplies.

     Phys.org reports:

"The southern North Sea receives the contrast agents primarily via the Rhine, Ems, Weser, and Elbe rivers, but also the River Thames," says Dr. Dennis Krämer, head of the Soil Analysis Department at the Federal Institute for Geosciences and Natural Resources in Hanover, who is the lead author of the North Sea study and an adjunct professor at Constructor University.

"The Baltic Sea water, in turn, receives the gadolinium contrast agents from, among other sources, the Vistula and Oder rivers, which—like other rivers in Poland and almost everywhere in Europe—are contaminated with this anthropogenic gadolinium," adds Addis Alemu, a doctoral candidate in the EU project "PANORAMA," who is investigating rare earth elements in rivers and lakes across Europe.

     Currently, there appears to be no danger from the contrasting agents as they are well below limits, but their concentration in these areas, especially coastal sea areas, is expected to continue to increase.

"Next, we will evaluate how stable the various MRI contrast agents in seawater actually are. We investigate how long it takes for these chemical compounds to degrade in seawater, releasing the gadolinium and making it bioavailable. The concentrations of anthropogenic gadolinium are currently well below dangerous levels.

      

 

References:

 

North and Baltic seas show widespread contamination by MRI contrasting agents. D. Scott Peterson. Phys.org. November 26, 2025. North and Baltic seas show widespread contamination by MRI contrasting agents