Toward Sustainable Clinical Chemistry: Waste Quantification and Reduction Strategies from Testing on 4 Commonly Used...

Clinical laboratories are essential to healthcare but generate substantial environmental waste through high test volumes, single-use materials, and energy-intensive instrumentation.

We quantified the solid and liquid waste generated during the performance of basic metabolic panels-the most routinely ordered chemistry panel in hospitalized patients-across 4 commonly used automated chemistry analyzers in US laboratories. Waste generated was categorized into pre- and postanalytical components common to all analyzers, instrument-specific testing-phase waste, and chemical constituents with known environmental hazards.

In performing 100 000 panels, total solid waste exceeded 4000 kg, with over 50% attributed to phlebotomy supplies. Analyzer-specific dry waste varied 24-fold from 67 to 1637 lb (30.4-744 kg). Liquid waste varied 32-fold, from 10.8 to 346.6 L. Heat generation varied 4-fold from 134 853 to 517 925 British thermal units (142 277-546 440 kJ). Reagents sometimes contained sodium azide and other aquatic toxins. Estimated carbon footprint from various categories of pre- and postanalytical waste varied 33-fold from 205 to 6805 kg CO2e, equal to 215 to 7130 miles (346-11 475 km) driven in a mid-sized car.

Our findings highlight substantial variation in waste output across platforms performing identical tests. Reducing laboratory waste will require coordinated interventions, from minimizing unnecessary test orders and optimizing sample collection to selecting low-waste analyzers and integrating sustainability into procurement policies. As high-throughput environments with well-established quality systems, clinical laboratories are well positioned to lead healthcare's broader sustainability efforts, demonstrating how operational excellence and environmental responsibility can align. Quantifying diagnostic waste is a critical first step toward integrating environmental stewardship into patient care.