Ripple Effect: Safety, Cost, and Environmental Concerns of Using Sterile Water in Endoscopy

The gastroenterology societies are committed to reducing the carbon footprint of endoscopies and hence, re-examining waste-generating practices. One such practice is the recommendation to use sterile water during endoscopy for endoscopy lens cleaning and colon irrigation. We critically reviewed all published medical literature and guidelines on the safety of the type of water used in endoscopy. We calculated the cradle-to-grave carbon footprint of a 1-L sterile water bottle and compared it to published studies on bottled drinking water. Guidelines recommending sterile water during endoscopy are based on limited evidence and mostly expert opinions. Referenced studies utilize care protocols that are not practiced. There is also considerable cross-referencing of review articles and guidelines. Two clinical studies directly comparing tap and sterile water in gastrointestinal endoscopy found tap water to be a safe and practical cost-saving alternative to sterile water. The calculated carbon footprint of bottled sterile water is 575 g CO₂ equivalent. No direct evidence supports the recommendation and widespread use of sterile water during gastrointestinal endoscopy procedures. It contributes to health-care waste and climate change and is costly. We recommend tap water be used to fill sterile water bottles until evidence shows the need for alternative practice. It would be prudent to re-evaluate guidelines and write new ones that consider harm to the environment and society in the provision of care to patients, especially when the intervention may be more harmful than the risk it aims to address.