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Endoscopy 2023; 55(10): 927-928
DOI: 10.1055/a-2120-4444
Editorial

28 kg of carbon dioxide per endoscopic procedure. Time to make green endoscopy a professional priority

Referring to Lacroute J et al. p. 918–926
Enrique Rodríguez de Santiago 
1   Gastroenterology and Hepatology, Hospital Universitario Ramón y Cajal, Universidad de Alcalá, IRYCIS, CIBERehd, ISCIII, Madrid, Spain
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About 2400 years ago, the Greek philosopher Theophrastus, a student of Aristotle, documented that human activity can alter the climate. In the 19th century, Professor Arrhenius proved that carbon dioxide (CO2) emissions play a major role in keeping our planet warm [1]. In the 20th and early 21st centuries, overwhelming evidence confirmed that human activities are the cause of the current climate crisis and that our way of life impacts the atmosphere and biosphere [2]. Climate change has already wrought visible consequences in the form of droughts, hurricanes, heatwaves, and unprecedented loss of biodiversity. Nobody should be surprised that a recent study predicted an ice-free Arctic summer in the next decade, even under a low emission scenario [3]. Indeed, a survey by the European Commission found that European citizens identify climate change as the single most serious problem facing the world [4]. Nonetheless, despite the healthcare sector accounting for about 4.4 % of greenhouse gas emissions [5], “green endoscopy” was born just 3 years ago when a group of physicians called for sustainability [6]. Subsequently, the European Society of Gastrointestinal Endoscopy was the first scientific society to raise awareness of the environmental impact of gastrointestinal (GI) endoscopy [5]. Other major GI societies have recently published position statements with similar aims [7].

So, the first question that one may ask is: what took us so long? The answer is complicated and multifactorial. Healthcare metrics have traditionally focused on direct patient or population outcomes and financial costs. Moreover, climate change is often perceived as a distant and unrelated problem that fails to trigger our innate threat-detection system, which is required to implement change [8]. In experimental psychology, this climate change myopia is termed “temporal discounting,” which refers to the tendency to choose immediate rewards over long-term, uncertain ones [8]. Physicians and other healthcare professionals have only very recently acknowledged the polluting impact of their activity or engaged in sustainable practices. GI endoscopy manufacturers, governments, and other agents involved in the healthcare chain have also failed to prioritize environmental sustainability in their agenda. Fortunately, green endoscopy seems to be a hot topic, so better late than never!

“...the findings confirm that the carbon footprint is invariably high and partially preventable through individual and institutional actions.”

In this issue of Endoscopy, Lacroute et al. [9] present the results of a retrospective study conducted in 2021 in an ambulatory GI endoscopy center. A total of 8524 procedures were performed. The authors calculated the carbon footprint with the help of a specialized company using dedicated software (Bilan Carbone). They estimated that the carbon footprint per endoscopic procedure was 28.4 kg of CO2 equivalents, nearly six times higher than that previously reported [10]. It is essential to give some context to this figure and analyze the methodology used to determine its accuracy.

Many endoscopists who read the Methods may feel that this is beyond a physician’s expertise. As performed by the authors, the involvement of engineers and specialized professionals is critical in conducting rigorous sustainability research. The authors should be commended for including both direct and indirect greenhouse gas emissions or, in other words, considering scope 1 (activities that an organization controls), scope 2 (emissions from energy use), and scope 3 (emissions from products and services an organization does not directly control). When emission factors were unavailable, the authors calculated the carbon footprints of products from monetary ratios (i. e. indirect estimation based on the purchase cost: the higher the cost, the higher the carbon footprint). The authors used monetary ratios to calculate the carbon footprints of medical and non-medical equipment. This is not surprising, considering that GI manufacturers do not publicly disclose the carbon footprint of their products and we lack life cycle assessment studies. The authors estimated travel-related greenhouse gas emissions based on a survey completed by patients and center staff. The details provided are insufficient to judge the validity and representativeness of the survey. Finally, the authors did not consider histopathological analysis or water consumption, and assumed that many single-use consumables were delivered from a European country, which may underestimate the true carbon footprint.

One of the striking findings is that patient and staff transport accounted for 45 % of the carbon footprint [9], above previously reported healthcare data. This percentage would likely be lower if the study were conducted in a better-connected hospital. Most patients travelled by car on a round trip of 41 km, only 2 % arrived on foot, and train use was anecdotal, which may not be the case for many institutions. Regardless, this finding has an important message: patient and staff awareness of the impact of mode of transport must be raised to minimize our carbon footprint. The second largest contributor was medical and non-medical equipment (e. g. computers, endoscopes, washer disinfectors), at 32 % of the overall carbon footprint. This domain is out of physician reach, indicating that the engagement of GI manufacturers to reduce the impact of their supply chain and disclose product carbon footprints are also vital. Similarly, the promotion of renewable energy at an institutional level is beyond the physician’s control but should be prioritized, given that energy consumption (12 % of the overall carbon footprint) was the third largest contributor. The proportional contribution of energy to the carbon footprint would probably be larger in other settings because the research was conducted in France, a country that obtains most of its electricity from nuclear energy, a low CO2 emission energy; indeed, nuclear energy provided 70.6 % of French electricity in 2019, vs. 10.1 % worldwide [11]. Contrary to what might be expected, consumables (7 %) and waste (3 %) were not the main contributors. Nonetheless, their impact should not be disregarded. No advanced GI endoscopy procedures were performed, which may not represent the reality for high-volume centers performing more resource-intensive procedures.

In conclusion, this well-conducted research provides major insight into potential avenues for green endoscopy. The results show that the carbon footprint of endoscopy is highly dependent on local circumstances and that granular data are insufficient to calculate the exact carbon footprint. Nonetheless, the findings confirm that the footprint is invariably high and partially preventable through individual and institutional actions. The coordinated effort of physicians, GI endoscopy manufacturers, and governments is the only way to build a sustainable future for endoscopy.



Publication History

Article published online:
27 July 2023

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Refers to:

The carbon footprint of ambulatory gastrointestinal endoscopyEndoscopy 2023; 55(10): 918-926
DOI: 10.1055/a-2088-4062