Environmental sustainability of medical imaging

Environmental impact of medical imaging is ill-defined and poorly recognised but can vary by a factor of 100 or 1 000 between one test or the other. One echocardiogram produces 2 Kg and a 3 Tesla magnetic resonance imaging produces 200 to 300 kg of carbon dioxide (CO₂) equivalent. For 2016, CO₂ emissions for magnetic resonance imaging and computed tomography calculated in 120 countries accounted for 0.77% of global emissions. In imaging justification, we usually consider benefit, cost, and risk including long-term cancer risk. Environmental footprint should be included, since there is a fourth partner in the imaging deal: not only the patient, the physician, the payer, but also the planet. Medical imaging is an important source of carbon footprint in the global scale. Environmental impact of each imaging examination might be spelled-out and missing data provided to bridge the knowledge gap. Research may develop a catalogue of carbon footprints associated with specific test modalities, and provide an updated estimation of medical imaging impact on global carbon footprint, promoting new approaches towards a progressive de-carbonization of testing with climate-neutral choices.