Toward Green Endoscopy in a Warming World: Bridging Environmental Footprints and Everyday Practice in Japan

Abstract

Climate change has begun to affect routine clinical practice; heat-related illnesses, supply chain disruptions, and disaster-related care are now reported daily. Greenhouse gas (GHG) emissions are well-recognized as a major cause of global heating. Notably, it has been estimated that the healthcare sector causes approximately 4.4% of total GHG emissions worldwide [1]. Gastrointestinal (GI) endoscopy is used for screening, diagnostic, and therapeutic purposes and plays a significant role in any healthcare facility. As its use has grown over time, GI endoscopy units may increasingly become a major waste-producing area of the hospital. Direct and indirect GHG emission can be classified into emissions in pre-, during, post-endoscopy. In pre-endoscopy, GHG includes staffs and patients travel, freights of medical equipments or materials, medical and non-medical equipment (endoscope washer disinfectors, endoscopy system), consumables (drugs, devices). During endoscopy, emissions come from gas/electricity energy and medical gases (CO2). Emissions from staffs travel and waste (water, hazardous and non-hazardous equipments) were included in post-endoscopy. The European Society of Gastrointestinal Endoscopy (ESGE) has released a statement on the need to increase the implementation of sustainable daily practices [2]. However, awareness of this environmental issue remains limited among healthcare professionals [3].

It became more challenging to focus on medical waste management in GI endoscopy, as medical workers experienced increased demand for personal protective equipment, such as masks, glasses, gowns, and gloves during the COVID-19 pandemic. A recent web-based survey conducted by the ESGE Green Endoscopy Working Group revealed that many participants did not consider GI endoscopy to be a large contributor to climate change; only 41% of European participants thought that they needed to optimize the appropriate use of GI endoscopy procedures, and 34% thought it was important to reduce reliance on single-use devices [3]. More recently, a questionnaire study among 114 Japanese healthcare professionals revealed that many were interested in the ecological impacts of their practices, in recycling the packaging of devices, and in making improved device selections from an ecological perspective; however, on the other hand, 84% of Japanese responders prioritized cost over ecological concerns when selecting a device, and only 12% reported that they could not reduce unnecessary endoscopy procedures [4]. Although these data could not be compared directly due to different backgrounds in Europe and Japan, the current awareness and attitude on this environmental issue could be described.

In a recent issue of Digestive Endoscopy, Baddeley and Hayee comprehensively review the current status and challenges of “green endoscopy” [5]. Their review emphasizes the need to carefully balance environmental achievements with clinical safety and data-based efficiency.

First, strict infection control requirements can be balanced with recycling efforts, although these issues sometimes appear to be in absolute conflict. The authors propose a “triple bottom line” of patient safety, cost, and environment by improving waste separation, introducing a feasible recycling system, and prioritizing the selection of environmentally low-impact equipment, without compromising infection control. A recent pilot study suggests that it may not be essential to change all personal protective equipment for each endoscopy case because the bacteria detected on disposable gowns after an endoscopy procedure were non-pathogenic [6]. Because infection prevention guidelines remain the primary requirement, these data within those standards could be useful for improving waste management without compromising patient safety.

Second, from this perspective, the single-use disposable endoscope is a hot topic. Single-use endoscopes eliminate the need for reprocessing (which requires water, electricity, and chemicals) and reduce infection risks; however, they also significantly increase solid waste and manufacturing-related emissions. A recent randomized noninferiority pilot trial demonstrated that a novel disposable colonoscope achieved 100% cecal intubation and was noninferior to a reusable colonoscope for routine examinations, providing acceptable imaging and maneuverability, despite slightly longer procedure times and lower adenoma detection rates [7]. However, this single-use endoscope carries a higher cost than reusable endoscopes, even when accounting for the cost of a single reprocessing, and the single-use endoscope results in substantial plastic and electronic waste. In the review, the authors discuss how to consider balancing the risk and benefit when selecting a single-use endoscope. In my perspective, given its costly and environmentally hazardous nature, a single-use endoscopy would be beneficial under critical conditions: high infection-risk scenarios or emergency/disaster contexts.

Third, the largest component of the environmental impact is from the supply chain. Material and weight differences in endoscopic equipments can be associated with different emissions [8]. However, in their review, the authors point out that true calculations are unfeasible because manufacturing data are not usually available based on the corporation confidentiality. They proposed that medical societies could request that companies provide the relevant manufacturing data.

The authors also issue several cautions. Although a recent prospective study clarifying the emission impacts of endoscopy procedures is somewhat representative [9], carbon footprint calculations would be variable under different hospital-based conditions. In some rural regions, patient and staff travel would be the most significant source of emissions. On the other hand, at an urban institution in a hot region, energy consumption for ventilation and air conditioning might be the predominant contributing factor. Furthermore, the reprocessing cost would be higher in regions with high-carbon energy conditions. Consequently, it is difficult to generalize a universal per procedure emissions value.

Additionally, a significant trade-off must be considered in efforts to reduce unnecessary procedures; the risk of overlooking a significant disease must be weighed against the environmental benefits. Therefore, mitigation strategies must be tailored to the dominant emission sources of individual facilities and situations. In a French post hoc eco-audit of the RESECT-COLON randomized trial, piecemeal endoscopic mucosal resection (pEMR) was compared with endoscopic submucosal dissection (ESD) for large colonic adenomas [10]. The results showed that ESD had a higher carbon footprint than pEMR (73.2 vs. 63.5 kg CO₂e), due to a longer procedure time and greater device use. However, when accounting for surveillance and recurrence management over an 18-month follow-up, the cumulative emissions with ESD were lower, by 17 kg CO2e per patient, compared to pEMR. This difference was because, in both groups, approximately half of the total emissions arose from patient transport for the endoscopic procedures. Frequent hospital visits and travel emerged as major sources of environmental impact.

These data enhance two of the most important themes in this review. First, sustainable endoscopy cannot be simplified to counting the kg CO₂e from a single procedure. We must evaluate entire care pathways, including surveillance strategies and the geography of service delivery. The authors intended to emphasize the limitation of focusing carbon-based discussion alone, rather than to advocate reducing across-the-board reductions. Second, decisions that look eco-friendly at the index procedure level may prove less sustainable once accounting for repeated visits, retreatments, and travel. Notably, for older adults with various morbidities, each colonoscopy also includes the burden of bowel preparation, time off from work or caregiving, and reliance on family or medical transport. Therefore, a strategy that meaningfully reduces the number of such episodes may be more considerate toward both the environment and the patient, even if it appears more resource-intensive on the day of treatment.

Beyond providing guidance on navigating complex and high-level changes, the authors also emphasize the value of “small wins,” like powering off equipment, which have symbolic value. On the other hand, large-scale reductions can be achieved through facility management, such as by optimizing air exchange rates during non-working hours. Other effective interventions can include staff education to reduce “regulated medical waste,” and choosing suppliers based on environmental performance.

In summary, evidence suggested that green endoscopy is an emerging but insufficiently recognized field. There is currently no one-size-fits-all solution. The recent review article provides endoscopists an opportunity to consider sustainability as a professional responsibility, while balancing clinical efficacy, safety, and equity. Additionally, this review urges us to consider counting not only the kilograms of waste in the endoscopy room but also the full supply chain pathway—including why a test is performed, how patients reach the hospital, how our units are powered, how we select and reprocess devices, and how we measure success. This will not be an easy conversation, but this review article provides a unique launchpad from which to start thinking and discussing the subject.

The author drafted and reviewed the manuscript.

The author has nothing to report.

The author has nothing to report.

The author is an editorial board member of Digestive Endoscopy, has received research grants from The Japanese Foundation for Research and Promotion of Endoscopy and The Japanese Gastroenterological Association, has received speaker honorariums from the OLYMPUS Company and the Boston Scientific corporation, and holds an advisory role with the OLYMPUS Company.

This article is linked with Baddeley and Hayee papers. To view the article visit http://doi.org/10.1111/den.70080.