Optimization of a new multi-reagent procedure for quantitative mussel digestion in microplastic analysis

Over the last few years, different digestion protocols have been proposed to extract microplastics from mussels, an important product from aquaculture and a relevant economic resource, always scrutinized as a potential pollutant concentrator. In this study, a full factorial experimental design technique has been employed to achieve efficiency in removing biological materials while maximizing the recoveries of five common microplastics (polyethylene, polystyrene, polyethylene terephthalate, polypropylene and polyamide). A robust setpoint was calculated, 2.5% potassium hydroxide at 60 degrees C for 3 h with 5% hydrogen peroxide and 2.7% of methanol, permitting the quantitative digestion of mussel tissues and recovery of microplastics. These experimental conditions were successfully used to digest whole mussels bought from a local market, which possess high levels of microplastic contamination (41 items/g dry weight). The results highlight the importance of optimizing protocols to develop robust, easy to use and cheap quantitative approaches for analysing microplastic accumulation in edible organisms.

Automated summary

Different digestion protocols have been proposed to extract microplastics from mussels, with a robust setpoint identified in this study. The optimized protocol successfully digested mussel tissues and recovered microplastics, highlighting the importance of developing efficient and cost-effective methods for analyzing microplastic accumulation in edible organisms.