Contrast Media-driven Anthropogenic Gadolinium: Knowns and Unknowns.

Gadolinium-based contrast agents (GBCAs) have augmented the capabilities of MRI, which has led to their widespread and increasing use in radiology practice. GBCAs are introduced into the environment through disposal of unused product and elimination after intravenous injection, both primarily via liquid dispersion into the environment. This human introduction of gadolinium into the environment, referred to as anthropogenic gadolinium, is associated with the detection of gadolinium in water systems, raising concerns for potential adverse impact and prompting certain mitigation actions. This article summarizes the existing knowledge and problem scope, conveys the relevant underlying chemical principles of chelate dissociation, and offers an inferred perspective that the magnitude of the problem is most unlikely to cause human harm. The merits and limitations regarding possible mitigation tactics, such as collecting urine after GBCA administration, use of lower-dose high-relaxivity macrocyclic GBCAs, and the option for virtual contrast-enhanced examinations, will be discussed. Finally, the potential for monitoring gadolinium uptake in bone will be presented, and recommendations for future research will be offered. © RSNA, 2024 See also the article by Ibrahim et al in this issue. See also the article by McKee et al in this issue.