"Dirty Dry Eye"- A waste volume analysis from topical therapy in keratoconjunctivitis sicca

The healthcare system is responsible for around 5% of CO₂ emissions globally and in Germany. So far, there are no data on the amount of waste from dry eye disease (DED) therapy in ophthalmology. The aim of this project was to evaluate the amount and type of waste from single- and multi-dose units (SDU/MDU) generated by eyedrops used to treat DED in Germany.

The net waste weight (outer/inner packaging, instruction leaflet, empty container) from factory-sealed products was determined using a precision scale. Based on prescription data from PharMaAnalyst, a database of medical prescriptions from over 70 million patients in Germany, the total annual waste volume for 2016-2021 and the net weight of a 30-day treatment were calculated.

The total annual waste volume increased significantly (p < 0.0001) from 7.13 tons in 2016 to 20.64 tons in 2021. A 30-day treatment with MDUs (without/with filter) results in a significantly lower mean waste volume (paper: SDU 24.3 ± 18.7 g; MDU 4.8 ± 1.7 g/8.8 g ± 1.7 g; SDU/MDU p = 0.0003, with filter p = 0.0034; plastic: SDU 35.0 ± 4.0, MDU 6.6 ± 0.7 g/ 15.1 g ± 5.8 g, SDU/MDU p < 0.0001, with filter p < 0.0001).

Prescription-based treatment of DED in Germany causes an increasing and substantial waste volume. The use of SDUs is considerably more resource-intensive than MDUs. Due to the large and rising number of patients suffering from DED improvements in packaging could considerably reduce the CO₂ footprint of DED treatment.