Reviewed by Lexie CornerApr 7 2025
A team led by Brent Wagner, MD, a professor in the University of New Mexico's School of Medicine Department of Internal Medicine, conducted a study published in the journal Magnetic Resonance Imaging. The study aimed to investigate the formation of nanoparticles that have been associated with significant health issues in the kidneys and other organs.
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Researchers at the University of New Mexico have found that oxalic acid, a compound found in many foods, can produce gadolinium nanoparticles in human tissues. Gadolinium is a rare-earth metal used in MRI scans, and its contrast agents are administered to enhance image clarity.
The worst disease caused by MRI contrast agents is nephrogenic systemic fibrosis. People have succumbed after just a single dose.
Brent Wagner, MD, Professor, Department of Internal Medicine, School of Medicine, University of New Mexico
According to Wagner, gadolinium-based contrast agents are typically bound to other molecules and eliminated from the body, with most individuals experiencing no adverse effects. However, previous studies have detected gadolinium particles in the kidneys, brain, blood, and urine of individuals—even years after exposure—despite the absence of symptoms.
This raises two key questions: why do some individuals experience health issues while most do not, and how do gadolinium particles separate from the contrast agent molecules?
Almost half of the patients had been exposed only a single time, which means that there is something that is amplifying the disease signal. This nanoparticle formation might explain a few things. It might explain why there is such an amplification of the disease. When a cell is trying to deal with this alien metallic nanoparticle within it, it is going to send out signals that tell the body to respond to it.
Brent Wagner, MD, Professor, Department of Internal Medicine, School of Medicine, University of New Mexico
Wagner’s team focused their study on oxalic acid, a compound found in many plant-based foods such as spinach, rhubarb, most nuts, berries, and chocolate, as it binds to metal ions. This process contributes to the formation of kidney stones, as oxalate binds to calcium. Additionally, when individuals consume vitamin C-rich foods or supplements, their bodies produce oxalic acid.
In test tube experiments, the researchers found that oxalic acid caused small amounts of gadolinium to precipitate out of the contrast agent, forming nanoparticles that subsequently entered cells in multiple organs.
Wagner added, “Some people might form these things, while other do not, and it may be their metabolic milieu. It might be if they were in a high oxalic state or a state where molecules are more prone to linking to the gadolinium, leading to the formation of the nanoparticles. That might be why some individuals have such awful symptoms and this massive disease response, whereas other people are fine.”
This discovery may provide a potential strategy for mitigating some of the risks associated with MRI scans, Wagner noted.
Wagner added, “I would not take vitamin C if I needed to have an MRI with contrast because of the reactivity of the metal. I am hoping that we are getting closer to some recommendations for helping these individuals.”
The team is now working on methods to identify individuals most at risk from gadolinium contrast agents. They are creating a global patient registry that will include blood, urine, fingernail, and hair samples to provide evidence of gadolinium accumulation in the body.
Wagner concluded, “We want to get a lot more information to come up with the risk factors that relate to those with symptoms. We are going to ask about what medical conditions you had at the time of exposure, what medications you are on, and we want to include dietary supplements because that might piece it all together why some people have symptoms, whereas others seem to be impervious.”