Collaboration to reduce contrast agents in river water

Gadolinium-based contrast agents (GBCA) are important for MRI scans, but they also end up in our water via the sewage system, which is bad for the environment and our drinking water. Even if doctors only use them in small amounts per patient, their use worldwide causes a lot of GBCA in rivers. The RIWA-Rhine Foundation is actively seeking cooperation with radiologists to reduce the use and emission of GBCA.

To tackle this problem, all stakeholders need to work together, including the makers of GBCA, doctors and patients. For example, doctors, especially radiologists, can use less contrast agent during a scan and think better about how they administer it. Moreover, alternatives to disposal through the sewer deserve attention.

In a first scientific article, RIWA-Rhine, together with radiologists, described how GBCA works, how it gets into the environment, and what options there are to limit the damage. That article found great resonance in the medical community, so the collaboration has now continued in a second article. If we are smart about the use of GBCA, we can protect the environment and still make good diagnoses. It is important that doctors are aware of these issues so that they can make better choices and contribute to a cleaner world.

Read the articles:

Tackling the increasing contamination of the water supply by iodinated contrast media

Review of strategies to reduce the contamination of the water environment by gadolinium-based contrast agents

Study on consequences of intake closure in case of prolonged drought

Deltares conducted research into the relationship between Rhine and Meuse discharge on the one hand and the occurrence of water intake problems for drinking water companies on the other. Many factors determine whether an intake closure is necessary. This makes a direct relationship between low river discharge and the number or length of intake closures difficult to demonstrate. But during prolonged droughts, the impact of any closure will be greater because the closure will last longer.

Previous studies (e.g. Van Vliet and Zwolsman 2008) show that water quality is negatively affected by summer drought. The decline in water quality during summer drought is related to both high water temperatures and low discharges. Looking only at the discharges, only some industrial chemicals show a direct relationship with the discharge, according to Deltares. For many other substances, no relationship was found; several processes are at play there;

  1. the degradation process depends on the water temperature,
  2. during a low-water period there is often little precipitation and thus less leaching,
  3. emissions depend on the application period.

It is therefore not trivial that more intake stops can actually be expected during low water. This does not detract from the fact that during calamities, the size of the discharge does matter, during low discharges, emissions have an impact on water quality for a longer period and thus on the duration of intake stops.

Looking ahead, KNMI predicts that low-water situations will become more frequent. Besides discharge, the number and duration of intake stops will depend on emissions, water temperature, post-purification possibilities and the occurrence of calamities.

Download the report (in Dutch)