Gastrointestinal endoscopy is the third largest contributor to hospitals’ environmental footprint. Colonoscopy, among the most performed endoscopic procedures, is considered to have a significant environmental footprint, yet the exact impact is unknown. We analyzed the material flow of diagnostic colonoscopy procedures and identified opportunities for reducing their environmental impact.  

A single-center material flow analysis (MFA) was conducted during a normal work week with diagnostic colonoscopy procedures. Waste was collected, weighted, and categorized by product type. The material composition was identified. Using visual mapping, we identified which products were used and disposed of at each stage of the procedure.   

Fifteen diagnostic colonoscopy procedures were audited. Mean total waste mass of a colonoscopy procedure was 0.58 ± 0.01 kg, with a mean of 46 products per procedure. This equals an average waste mass of 1169 kg for all diagnostic colonoscopy procedures performed annually in this hospital. Plastic-based products constituted the largest product category (22.67%). Nitrile made up the largest material category (14.1% of the total weight of materials). The total estimated carbon footprint for all analyzed waste was 1.77 kgCO₂e, with nitrile and polypropylene (PP) being the largest contributors. 

Most products were used and disposed in the preparation stage of the colonoscopy procedure.  

Plastic-based materials formed the largest contributor to the total used product weight, with nitrile being the most frequently used material type (14.1%). 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 sustainable opportunities.