By Abbas Nazil
Computerized tomography scanners are significant contributors to health care sector carbon emissions, with electricity use during operation emerging as the single largest source of their environmental impact, according to a new analysis released by the National Academy of Sciences through its Climate Collaborative initiative.
The brief examines carbon emissions associated with CT scanners across their life cycle and identifies key hotspots where targeted interventions could substantially reduce the climate footprint of radiology services.
Existing research cited in the analysis indicates that pathology and radiology services together may account for nearly 10% of total health care system emissions, underscoring the importance of addressing diagnostic imaging in broader decarbonization strategies.
The study summarized in the brief assessed a radiology department in the southeastern United States with more than a decade of operation, assuming a 10-year lifespan for CT scanners while excluding end-of-life disposal impacts.
Electricity consumption during scanning was identified as the primary emissions hotspot, followed by image processing and digital storage requirements, disposable medical supplies, and the production of imaging equipment.
Notably, the production and laundering of patient linens used during scans were found to contribute more than 10% of the department’s total carbon footprint.
By contrast, the manufacture of contrast agents and transportation of equipment represented comparatively minor sources of emissions.
When CT scanners are evaluated within the broader ecosystem of supporting infrastructure, including digital systems and ancillary equipment, their direct production, maintenance, transport, and operational electricity account for less than half of total associated emissions.
The brief outlines several strategies to reduce emissions, beginning with avoiding unnecessary imaging and limiting overuse of disposable supplies.
Clinicians are encouraged to consider alternative diagnostic methods or smaller portable imaging units when full CT scans are not medically required.
Hospital administrators are advised to extend the operational life of scanners beyond the assumed 10-year period to lower per-scan emissions.
Manufacturers and procurement officials are urged to prioritize energy-efficient equipment capable of low-power idling or shutdown modes and to transition facilities toward renewable electricity sources.
The analysis draws on findings from Thiel et al. 2025 in the journal Radiology and was prepared by experts affiliated with Northeastern University and the Sustainable Medicines Partnership as part of the Climate Collaborative’s efforts to stimulate discussion on health care sustainability.