Iodinated contrast media (ICM) can easily find their way into public water systems, but radiologists can cut down on waste, according to a talk delivered September 5 at the International Society for Computed Tomography (ISCT) meeting in Brussels, Belgium.
In his presentation, Mateusz Chodorowski, MD, from Centre Hospitalier Landerneau in France, outlined ways that contrast media waste occurs and strategies that imaging departments can implement to reduce waste.
“Reducing ICM pollution is the same as all the sustainability efforts we can make,” Chodorowski said. “We can’t do it alone. It’s all of us.”
ICM enters water systems in two primary ways: by contents being poured down sinks and/or patients releasing contrast waste through their urine. Wastewater treatment plants are incapable of removing this waste, and when ICM interacts with chlorine and chloramine, it creates iodinated disinfection byproducts, which are cytotoxic and genotoxic. Previous studies have suggested that these byproducts are present in freshwater samples in several European countries.
Chodorowski cited a 2012 report that suggested that ICM can represent up to 80% of a hospital’s pharmaceutical waste. And while recycling bags for contrast are available, these are later burned and lead to waste affecting air quality.
Chodorowski said imaging departments and health systems in general can take several approaches to reducing ICM waste. These include the following:
Reduce the use of contrast by practicing "shortage management," even in situations where hospitals are not facing contrast shortages.
Assess the need for contrast use in patients with certain conditions.
Adjust for individual injection volume for patients, such as fat-free mass.
Use low kVpeak, photon-counting CT (PCCT), and AI to reduce doses.
Chodorowski also highlighted the promise that multipatient injectors hold for reducing waste. He and colleagues led a study published this year, which found that over a three-month period, multipatient injectors led to 4.5 gallons of ICM waste, compared with 25 gallons of waste from single-patient injectors.
“I strongly encourage everyone to use multipatient injectors,” said Chodorowski, who also noted the potential cost savings.
The medical industry has also led efforts to recuperate and recycle ICM, but these have been mixed. GE Healthcare in 2006 built a recycling facility for ICM iodine in Norway, Bayer has its re:contrast program, and Bracco’s new-generation sites use reverse osmosis systems to recover between 87% and 90% of iodine from wastewater.
Finally, Chodorowski highlighted urine recuperation strategies with special toilets collecting urine for later ICM extraction. However, he noted that the specialized filters and toilet systems have high costs.
“We had to change the whole workflow of our department within our hospital because one filter can accommodate up to 500 patients,” he said. “So, you have to select patients who got injected. We had to put [digital] codes to not allow just anyone to use them.”
However, two pilot studies published in 2024 that used urine recuperation bags in the Netherlands and Germany showed success in reducing ICM waste by about 45%. The use of bags also led to little to no changes in workflows in the studies.
Successful waste reduction will take teamwork, Chodorowski said, including working with technicians, industry vendors, patients, and legislators to reduce waste in hospitals and public water systems.
