Environmental Sustainability in RadiologyGREENWATER 2NCT07620093
GREENWATER 2.0: Reducing Iodinated Contrast Agents in Hospital Wastewater
An observational study of Environmental Sustainability in Radiology and Iodinated Contrast Agent Recovery, run by I.R.C.C.S Ospedale Galeazzi-Sant'Ambrogio at 1 site in Italy.
Trial summary
The goal of this observational study is to learn if using a dedicated urine collection device after CT scans can help reduce the amount of iodinated contrast agent released into hospital wastewater in adult outpatients undergoing contrast-enhanced CT scans. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Environmental Sustainability in Radiology, Iodinated Contrast Agent Recovery
- What is being tested?
- Dedicated Urine Collection Device (Toilet)
- Type of treatment
- Injection or infusion, Medical device
- How many people
- 416 participants
- Where
- 1 siteItaly
- Study dates
- 10 Mar 2026to Dec 2026
- Phase
- Observational
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Study population: Adult outpatients aged 18 years or older undergoing clinically indicated contrast-enhanced CT scans with iodinated contrast agents at IRCCS Ospedale Galeazzi - Sant'Ambrogio. Participants will receive standard clinical care, with no modification to the CT protocol or contrast administration. The only study-specific procedure is the post-contrast use of a dedicated urine collection device after an approximately 60-minute waiting period.
Who may be able to join
- Adult patients aged 18 years or older.
- Patients scheduled for a clinically indicated contrast-enhanced CT scan with iodinated contrast agent.
- Patients able to provide written informed consent.
- Patients willing to wait approximately 60 minutes after contrast injection before using the dedicated urine collection device.
Who cannot join
- Patients unable to use the dedicated urine collection device for urine collection.
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Italy1 site, 1 recruiting
- Recruiting
IRCCS Ospedale Galeazzi - Sant'Ambrogio
Milan, MI, 20157
Moreno Zanardo, PhD, +390283502227, moreno.zanardo@grupposandonato.it
About this study
Official title: GREENWATER 2.0: Cutting Edge Solution for Reducing Iodinated Contrast Agents Via Post-Administration Collection Device
The goal of this observational study is to learn if using a dedicated urine collection device after CT scans can help reduce the amount of iodinated contrast agent released into hospital wastewater in adult outpatients undergoing contrast-enhanced CT scans.
The main questions it aims to answer are:
Read more
- Does the dedicated urine collection device improve patient acceptance and compliance with post-contrast urine collection?
- How much iodinated contrast agent can be recovered from urine collected after CT scans?
Participants will:
- Have their planned CT scan with iodinated contrast agent as part of their regular medical care.
- Wait in the radiology department for about 60 minutes after the contrast injection.
- Use a dedicated urine collection device before leaving the hospital.
- Answer short questions about their experience with the device.
This does not change the CT scan, the contrast agent used, or the standard clinical imaging procedure. The only additional procedure is the use of the dedicated urine collection device after the scan.
Read the detailed description
GREENWATER 2.0 is a single-center, prospective observational study with an additional urine collection procedure. The study will be conducted in the diagnostic imaging department of IRCCS Ospedale Galeazzi - Sant'Ambrogio and will include adult outpatients undergoing clinically indicated contrast-enhanced CT scans with iodinated contrast agents.
Iodinated contrast agents are widely used in CT imaging to improve diagnostic accuracy. After intravenous administration, these agents are predominantly eliminated unchanged through urine. Because conventional wastewater treatment may not fully remove iodinated contrast agent residues, urine collection shortly after contrast administration may represent a practical strategy to reduce their release into hospital wastewater.
The study builds on the previous GREENWATER study, which showed high patient willingness to participate in a sustainability-focused urine collection protocol after contrast-enhanced imaging. In GREENWATER 2.0, a dedicated urine collection device will be installed in the radiology department to make the collection process more practical and integrated into the clinical workflow.
Participants will undergo their scheduled CT scan according to standard clinical practice. The indication for the CT scan, the choice of iodinated contrast agent, the contrast dose, and the imaging protocol will not be modified for research purposes. After contrast injection, participants will be asked to remain in the radiology department for about 60 minutes and then use the dedicated urine collection device before leaving the hospital.
The study will evaluate whether this workflow is acceptable and feasible for patients in routine radiology practice. It will also assess the potential recovery of iodinated contrast agent residues from the collected urine. Additional information will be collected on the contrast agent administered, the volume of urine collected, the time between CT examination and device use, and patient-reported experience with the device, including comfort, ease of use, cleanliness, privacy, odor, waiting time perception, and clarity of instructions.
The study is expected to provide evidence on the feasibility of using a dedicated urine collection device in a hospital radiology department as a sustainability measure to reduce the environmental impact of iodinated contrast agents. The planned sample size is 416 participants, with recruitment expected to last approximately 12 months. The total study duration is expected to be approximately 18 months, including recruitment, data analysis, and preparation of the final study report.
- Being tested
- Dedicated Urine Collection Device (Toilet)
- Keywords
- Iodinated Contrast Agents, Contrast-Enhanced CT, Hospital Wastewater, Urine Collection, Environmental Sustainability, Radiology Sustainability
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Dedicated Urine Collection Device (Toilet)Device
A dedicated urine collection device installed in the radiology department for use after contrast-enhanced CT scans. Participants will undergo their CT scan according to standard clinical practice, with no change to the imaging protocol, contrast agent selection, or contrast administration. After iodinated contrast injection, participants will be asked to wait approximately 60 minutes and then use the dedicated device before leaving the hospital. The collected urine will be used to assess the potential recovery of iodinated contrast agent residues and the feasibility of this workflow in routine radiology practice.
| Study group | Role | What they receive |
|---|---|---|
| Adult Outpatients Undergoing Contrast-Enhanced CT | Adult outpatients scheduled for clinically indicated contrast-enhanced CT scans with iodinated contrast agents. Participants will undergo their standard CT examination with no change to the imaging protocol or contrast administration. After contrast injection, they will be asked to wait approximately 60 minutes in the radiology department and then use a dedicated urine collection device before leaving the hospital. Receives: Device: Dedicated Urine Collection Device (Toilet) |
What is being measured
The primary outcome is the main question the study is designed to answer.
Patient Acceptance and Compliance With Post-Contrast Urine Collection
Proportion of eligible participants who agree to participate in the study and complete the post-contrast urine collection procedure using the dedicated urine collection device after contrast-enhanced CT.
Measured: At the time of the CT examination, up to 60 minutes after contrast injection
Secondary outcomes (1)
Potential Recovery of Iodinated Contrast Agent From Collected Urine
Amount or proportion of iodinated contrast agent recovered from urine collected using the dedicated urine collection device after contrast-enhanced CT, based on the administered contrast agent and urine analysis.
Measured: At the time of the CT examination, up to 60 minutes after contrast injection
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted2 Jun 2026
- Study start10 Mar 2026
- Primary completionSep 2026 (estimated)
- Study completionDec 2026 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Environmental Sustainability in RadiologyStudies of the same condition, open and under way.
- More trials run by I.R.C.C.S Ospedale Galeazzi-Sant'AmbrogioThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Cohort
- Time perspective
- Prospective
- Enrolment
- 416 participants (estimated)
Sponsor and investigators
- Lead sponsor
- I.R.C.C.S Ospedale Galeazzi-Sant'Ambrogio
- Sponsor type
- University, hospital or other
- Collaborators
- Bracco Imaging S.p.A.
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07620093
- Sponsor's protocol ID
- GREENWATER 2.0
- Acronym
- GREENWATER 2
- Status last verified
- Jun 2026
- First submitted
- 27 May 2026
- Last updated
- 24 Jun 2026
- Results posted
- No
- Data monitoring committee
- Yes
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 24 Jun 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- GREENWATER 2.0: Cutting Edge Solution for Reducing Iodinated Contrast Agents Via Post-Administration Collection Device
- ClinicalTrials.gov ID
- NCT07620093
- Acronym / sponsor ID
- GREENWATER 2 / GREENWATER 2.0
- Keywords
- Iodinated Contrast Agents, Contrast-Enhanced CT, Hospital Wastewater, Urine Collection, Environmental Sustainability, Radiology Sustainability
- Study type
- Observational
- Recruitment status
- Recruiting
- Enrolment
- 416 participants (estimated)
- Lead sponsor
- I.R.C.C.S Ospedale Galeazzi-Sant'AmbrogioUniversity, hospital or other
- Collaborators
- Bracco Imaging S.p.A.
- Study start
- 10 Mar 2026 (actual)
- Primary completion
- Sep 2026 (estimated)
- Study completion
- Dec 2026 (estimated)
- First posted
- 2 Jun 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The goal of this observational study is to learn if using a dedicated urine collection device after CT scans can help reduce the amount of iodinated contrast agent released into hospital wastewater in adult outpatients undergoing contrast-enhanced CT scans.
The main questions it aims to answer are:
- Does the dedicated urine collection device improve patient acceptance and compliance with post-contrast urine collection?
- How much iodinated contrast agent can be recovered from urine collected after CT scans?
Participants will:
- Have their planned CT scan with iodinated contrast agent as part of their regular medical care.
- Wait in the radiology department for about 60 minutes after the contrast injection.
- Use a dedicated urine collection device before leaving the hospital.
- Answer short questions about their experience with the device.
This does not change the CT scan, the contrast agent used, or the standard clinical imaging procedure. The only additional procedure is the use of the dedicated urine collection device after the scan.
Detailed description
GREENWATER 2.0 is a single-center, prospective observational study with an additional urine collection procedure. The study will be conducted in the diagnostic imaging department of IRCCS Ospedale Galeazzi - Sant'Ambrogio and will include adult outpatients undergoing clinically indicated contrast-enhanced CT scans with iodinated contrast agents.
Iodinated contrast agents are widely used in CT imaging to improve diagnostic accuracy. After intravenous administration, these agents are predominantly eliminated unchanged through urine. Because conventional wastewater treatment may not fully remove iodinated contrast agent residues, urine collection shortly after contrast administration may represent a practical strategy to reduce their release into hospital wastewater.
The study builds on the previous GREENWATER study, which showed high patient willingness to participate in a sustainability-focused urine collection protocol after contrast-enhanced imaging. In GREENWATER 2.0, a dedicated urine collection device will be installed in the radiology department to make the collection process more practical and integrated into the clinical workflow.
Participants will undergo their scheduled CT scan according to standard clinical practice. The indication for the CT scan, the choice of iodinated contrast agent, the contrast dose, and the imaging protocol will not be modified for research purposes. After contrast injection, participants will be asked to remain in the radiology department for about 60 minutes and then use the dedicated urine collection device before leaving the hospital.
The study will evaluate whether this workflow is acceptable and feasible for patients in routine radiology practice. It will also assess the potential recovery of iodinated contrast agent residues from the collected urine. Additional information will be collected on the contrast agent administered, the volume of urine collected, the time between CT examination and device use, and patient-reported experience with the device, including comfort, ease of use, cleanliness, privacy, odor, waiting time perception, and clarity of instructions.
The study is expected to provide evidence on the feasibility of using a dedicated urine collection device in a hospital radiology department as a sustainability measure to reduce the environmental impact of iodinated contrast agents. The planned sample size is 416 participants, with recruitment expected to last approximately 12 months. The total study duration is expected to be approximately 18 months, including recruitment, data analysis, and preparation of the final study report.
Study design
- Observational model
- Cohort
- Time perspective
- Prospective
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| Adult Outpatients Undergoing Contrast-Enhanced CT | – | Device: Dedicated Urine Collection Device (Toilet)Adult outpatients scheduled for clinically indicated contrast-enhanced CT scans with iodinated contrast agents. Participants will undergo their standard CT examination with no change to the imaging protocol or contrast administration. After contrast injection, they will be asked to wait approximately 60 minutes in the radiology department and then use a dedicated urine collection device before leaving the hospital. |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
- Study population
- Adult outpatients aged 18 years or older undergoing clinically indicated contrast-enhanced CT scans with iodinated contrast agents at IRCCS Ospedale Galeazzi - Sant'Ambrogio. Participants will receive standard clinical care, with no modification to the CT protocol or contrast administration. The only study-specific procedure is the post-contrast use of a dedicated urine collection device after an approximately 60-minute waiting period.
Key inclusion criteria (4 listed)
- Adult patients aged 18 years or older.
- Patients scheduled for a clinically indicated contrast-enhanced CT scan with iodinated contrast agent.
- Patients able to provide written informed consent.
- Patients willing to wait approximately 60 minutes after contrast injection before using the dedicated urine collection device.
Key exclusion criteria (1 listed)
- Patients unable to use the dedicated urine collection device for urine collection.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Dedicated Urine Collection Device (Toilet)A dedicated urine collection device installed in the radiology department for use after contrast-enhanced CT scans. Participants will undergo their CT scan according to standard clinical practice, with no change to the imaging protocol, contrast agent selection, or contrast administration. After iodinated contrast injection, participants will be asked to wait approximately 60 minutes and then use the dedicated device before leaving the hospital. The collected urine will be used to assess the potential recovery of iodinated contrast agent residues and the feasibility of this workflow in routine radiology practice. | Device | Adult Outpatients Undergoing Contrast-Enhanced CT |
Primary outcome
Patient Acceptance and Compliance With Post-Contrast Urine Collection
Time frame: At the time of the CT examination, up to 60 minutes after contrast injection
Proportion of eligible participants who agree to participate in the study and complete the post-contrast urine collection procedure using the dedicated urine collection device after contrast-enhanced CT.
1 secondary outcome
Potential Recovery of Iodinated Contrast Agent From Collected Urine
Time frame: At the time of the CT examination, up to 60 minutes after contrast injection
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 24 Jun 2026.
- Individual participant dataSharing planned: No
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Environmental Sustainability in Radiology and Iodinated Contrast Agent Recovery, run by I.R.C.C.S Ospedale Galeazzi-Sant'Ambrogio at 1 site in Italy.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 4 inclusion and 1 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 24 Jun 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Italy. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Luca Maria Sconfienza, MD, PhD (+390283502227, io@lucasconfienza.it), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Patient Acceptance and Compliance With Post-Contrast Urine Collection (time frame: At the time of the CT examination, up to 60 minutes after contrast injection). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 24 Jun 2026.