Quantification of Different Types of Waste and Batteries Associated With the Widespread Usage of Continuous Glucose Monitoring Systems

Background: People with diabetes benefit from continuous glucose monitoring (CGM) systems. A downside of these valuable aids for diabetes management is the generation of a tremendous amount of waste. This study aimed to quantify this CGM-related waste.

Method: Twenty-four used CGM sensors from two different manufacturers (8× FreeStyle Libre 2, 11× FreeStyle Libre 3, and 5× Dexcom G7) were dismantled manually and separated in case, circuit board, and battery. Each component as well as included packaging, applicator, and leaflet were weighed separately.

Results: Packaging, applicators, and leaflets accounted for most of the waste (FL2: 93.4 g; FL3: 58 g; G7: 108.1 g). The plastic case contributed mainly to the total sensor weight (FL2: 1.9 g/63% of 3.3 g; FL3: 0.5 g/49% of 1.1 g; G7: 1.9 g/59% of 3.2 g), whereas the weight of the electronic circuit board and battery varied (FL2: 0.8 g/25%, 0.4 g/12%; FL3: 0.2 g/17%, 0.4 g/34%; G7: 0.7 g/22%, 0.6 g/19%). Extrapolating these data based on annual worldwide usage of around 230 million glucose sensors, approximately 20,000 tons of packaging, applicators, and leaflets and 580 tons of glucose sensors are disposed of, including about 340 tons of casings, 130 tons of circuit boards, and 110 tons of batteries.

Conclusions: Our data highlight the potential for optimized resource utilization by reduction of packaging, sensor size, longer application periods, implementation of multiuse applicators, and the need for recycling options.