Opportunities to reduce the environmental impact of endoscopy: a detailed material flow analysis of diagnostic colonoscopy

Gastrointestinal endoscopy is the third largest contributor to hospitals' environmental footprints. Colonoscopies, among the most frequently performed endoscopic procedures, are considered to have a significant environmental footprint, yet their exact impact is unknown. We analyzed the material flow of diagnostic colonoscopy to identify opportunities for reducing its environmental impact.A single-center material flow analysis (MFA) was conducted during a week with diagnostic colonoscopy procedures. Waste was collected, weighed, and categorized by product type. The material composition was identified. Using visual mapping, we identified which products were used and discarded at each stage of the procedure.15 diagnostic colonoscopy procedures were audited. Mean (SD) waste mass per procedure was 0.58 (0.01) kg, including an average of 46 products. Extrapolated to the hospital's annual diagnostic colonoscopies, this equals approximately 1169 kg of waste. Plastic-based products constituted the largest product category (22.7%). Nitrile made up the largest material category (14.1% of the total weight of materials). The estimated carbon footprint for the analyzed waste was 1.77 kg CO₂e, with nitrile and polypropylene being the largest contributors. Most products were used and discarded in the preparation stage of the colonoscopy procedure.Plastic-based materials were the largest contributor to the total used product weight. These findings inform decision-makers in designing targeted interventions to reduce the environmental impact of diagnostic colonoscopy, for example by considering more sustainable materials such as fiber-based materials. The prepared visual map makes waste generation discussable among healthcare professionals, thereby supporting a collaborative approach to identify opportunities to improve sustainability.