Crises are an opportunity to interrogate what really matters. The covid-19 pandemic is no exception. There has been considerable debate about possible causal relationships between capitalism and inequalities, environmental damage and climate change on the one hand, and the pandemic on the other. Healthcare systems must begin to examine how they can reduce their environmental footprint and aim for zero-carbon emissions to stop impairing the health of the very people they are supposed to protect. 
In countries such as the United Kingdom and France, governments have promised investment and some form of resetting of their healthcare systems following the pandemic. These efforts should include a binding decarbonisation roadmap.
A recent report underlines that the healthcare sector generates 5% of global annual emissions – the equivalent of 514 coal power plants.  Published estimates consistently associate hospitals and pharmaceuticals with the biggest greenhouse gas emissions. 
Research has covered the carbon emissions of medical specialties from kidney conditions, ophthalmology, cataract surgery and plastic surgery.  Some countries have calculated their healthcare system’s entire environmental emissions and the available data shows wide variability: from 3.3% for Mexico to 5.5% for Spain and 7.9% for the United States. 
These studies underline that a substantial part of any given healthcare’s carbon footprint is indirect, mostly fuelled by its supply chain. For instance, among all surgical mini invasive procedures, the CO2 used in laparoscopic or robotically assisted surgery represents less than 0.1% of the global carbon footprint realised by laparoscopic surgery, while in the US healthcare suppliers and medical devices are responsible for 99.9% of the 355,621 tons of CO2 released there. 
Climate change negatively affects a number of health outcomes.  The public health damage caused by global emissions from the US healthcare system alone is equivalent to annual deaths related to avoidable medical errors. This damage is indirect and hard to estimate, as it is difficult to isolate the harm caused by emissions from the healthcare industry alone. This in turn makes awareness raising and action even more difficult.
Yet solutions exist to build a decarbonisation roadmap for the healthcare sector. Five suggestions should be applied urgently.
First, scientists should develop and deploy a systematic measure of care activities’ environmental footprint. This should include travel and transport (patients and their caregivers, and products), energy consumption, waste management, and medical devices or product use. Some national examples already stand as helpful benchmarks, but they are not yet sufficiently developed to be directly replicated and will need to be adapted locally to maximise cost-effectiveness.
Second, we must find the most effective way to disseminate compelling information to make this a priority among healthcare professionals and managers, and politicians. Decarbonisation is not currently a priority in many settings, and the post-pandemic context is likely to downgrade it further.
Third, a thorough public policy analysis is needed to identify the most cost-effective mix of regulation, intrinsic incentives and extrinsic incentives. A mix of policy instruments will be needed to move the market forward, including building standards, price incentives, and full disclosure of information. Stringent building standards applied to hospitals could help to reduce the health system’s carbon footprint, as buildings have huge untapped potential for energy efficiency. The International Energy Agency estimates that buildings’ energy performance per square metre needs to improve from a rate of 1.5% per year in the past decade to at least 2.5% per year over the next decade to 2025. Yet solutions already exist. For example, building control systems can deliver 30% energy savings by combining comprehensive automation, control and monitoring of energy use, with a payback of less than three years.
Fourth, decarbonisation in general implies significant investment and a decline in revenue for some industries, but this may not be the case for healthcare. There is a high degree of alignment between conserving resources, and so increasing environmental sustainability, and reducing costs. A massive change in waste management, including a reuse policy, is an obvious ecological measure likely to be associated with lower costs.
Fifth, we must cut easily avoidable emissions now. The following examples could have an immediate impact:
- stop the use of desflurane for general anaesthesia
- challenge systematic single-use for medical devices
- improve waste sorting and recycling
- promote remote consultation to decrease travel to and from clinic consultations.
These five suggestions will be difficult to deploy, given that after the pandemic subsides healthcare providers will have to cope with delayed procedures and untreated chronic diseases.  However, as both economies and healthcare systems are likely to be reshaped in the post-covid-19 era, implementing a transition to cutting carbon emissions in medicine is an obligation. The health impact of climate change is becoming increasingly obvious and it is high time we made healthcare cleaner and less harmful.
Jean-David Zeitoun is a researcher at the Centre of Clinical Epidemiology, Hôtel Dieu Hospital, Paris, and a medical practitioner at the Department of Gastroenterology and Nutrition, Saint-Antoine Hospital, Paris
Philippine de T’Serclaes is Global Head of Strategic Partnerships and Development at Schneider Electric
Jérémie H Lefèvre is Professor of Surgery in the Department of Digestive Surgery, Saint-Antoine Hospital, Sorbonne University, Paris
Competing interests: Philippe de T’Serclaes works for Schneider Electric (the views expressed in the article are those of the author and do not reflect an official view from her institution). No other competing interests declared.
- Sherman JD, MacNeill A, Thiel C. Reducing Pollution From the Health Care Industry. JAMA 2019.
- Malik A, Lenzen M, McAlister S, et al. The carbon footprint of Australian health care. Lancet Planet Health 2018;2:e27-e35.
- Woods DL, McAndrew T, Nevadunsky N, et al. Carbon footprint of robotically-assisted laparoscopy, laparoscopy and laparotomy: a comparison. Int J Med Robot 2015;11:406-12.
- Pichler P-P, Jacard IS, Weisz U, et al. International comparison of health care carbon footprints. Environ Res Lett 2019;14.
- Power NE, Silberstein JL, Ghoneim TP, et al. Environmental impact of minimally invasive surgery in the United States: an estimate of the carbon dioxide footprint. J Endourol 2012;26:1639-44.
- Patz JA, Frumkin H, Holloway T, et al. Climate change: challenges and opportunities for global health. JAMA 2014;312:1565-80.
- CovidSurg C, Nepogodiev D, Bhangu A. Elective surgery cancellations due to the COVID-19 pandemic: global predictive modelling to inform surgical recovery plans. Br J Surg 2020.