Sustainable strategy for preventing medical gadolinium from entering surface water

Abstract Gadolinium (Gd) is critical to diagnostic medicine but is an emergent micropollutant to surface water after use in magnetic resonance imaging and subsequent excretion in urine. Due to Gd being excreted as anionic or neutral complexes, diluted and mixed with contaminants, wastewater treatment plants remove less than a quarter of Gd from the treated effluent. Here, we describe how solid-phase adsorbents, well-established in wastewater treatment, capture and recover Gd-containing contrast agents from urine. We found that commercially available adsorbents capture Gd-containing contrast agents within the range of concentrations found in urine after magnetic resonance imaging. The ability to capture and recover, without the use of harmful acid or expensive apparatuses, is an elegant and impactful step beyond other solutions that involve collecting patient urine in disposable bags and burying them in landfills or using more complicated technology that requires large investments, energy, and acid. Finally, this study has the potential to reshape current practice in medical imaging by encouraging medical professionals, contrast-agent manufacturers, government authorities, and the general public to consider environmental sustainability and recovery and recycling of the critical mineral Gd when selecting contrast agents.