Assessing plastic waste associated with LC-MS/MS method validation procedures

The healthcare sector, and especially laboratory diagnostics, is a major contributor to climate change, accounting for an estimated 8 to 10% of France's total greenhouse gas emissions. This study aims to assess plastic waste associated with the validation of a LC-MS/MS method for monitoring tamoxifen and its active metabolite endoxifen in plasma.

A dedicated container was used to collect all plastic consumables employed throughout the method validation. At the end of the study, the total amount of waste was weighed to determine the environmental burden of the process. Method validation was performed according to ICH M10 guidelines.

The method met all EMA/ICH acceptance criteria, showing good linearity, accuracy within ± 15% (± 20% at LLOQ), precision ≤ 15%, and negligible carry-over. Recovery was moderate but reproducible, and analytes were stable for 24 h at room temperature in different matrices. Inter-laboratory comparison confirmed robustness with deviations < 15%. Plastic waste generated during the 39-day validation amounted to 5.7 kg (≈ 146 g/day).

The daily plastic packaging waste generated solely from method validation was approximately 1.5 times higher than the average daily plastic consumption per capita in the European Union. Certain stability studies, especially those assessing the stability of analytes in whole blood or plasma under well-controlled storage conditions, could probably be avoided or reduced.