Green laboratory through test ordering appropriateness and innovation

Objectives: Clinical laboratories play a vital role in healthcare but are also among the most resource-intensive hospital units. High energy and water consumption, extensive use of single-use plastics, and the generation of non-recyclable biomedical waste present major environmental challenges. This study aimed to quantify the environmental and economic burden associated with common and avoidable practices in clinical laboratory medicine, including: excessive blood collection, inappropriate test ordering, and unnecessary tube duplication in pre-analytical workflows. Methods: Real-world data from the Clinical Biochemistry Laboratory of the AOU Maggiore della Carità (Novara, Italy) for the year 2024 were analysed to quantify the environmental and economic impact of inappropriate test ordering based on minimum retesting intervals, as well as pre-analytical practices, including redundant sample tube collection and excessive blood volumes relative to analytical requirements. Results: Inappropriate retesting of selected biomarkers resulted in 2,931 unnecessary tubes, generating over 26.7 kg of avoidable waste. Redundant EDTA tubes for complete blood count, glycated haemoglobin, erythrocyte sedimentation rate, and haemoglobin electrophoresis led to 356.14 kg of excess waste, which could be eliminated through sample consolidation. In haematology, 264,834 CBC tests generated 2.62 tonnes of biological waste. For biochemistry, 3 million tests produced 36.98 tonnes of waste. Conclusions: Excessive blood collection and unnecessary test repetition contribute to significant but avoidable environmental and financial burdens. Pre-analytical interventions, such as reducing tube volume and consolidating tests, could prevent over 40 tonnes of waste and save more than € 60,800 annually in a single laboratory.