Reliable methodologies to determine microplastics in mussels: Enhanced digestion protocols, transference to gold-coated filters and determination via laser-based transflectance infrared spectrometry
Year: 2025
Type: article
Abstract: While several analytical strategies have been developed in the last years to determine MPs in marine ecosystems, reliable and fast analytical methods are still needed for monitoring filter-feeder seafood, such as mussels, intended for commercial use. A comprehensive review of state-of-the-art methodologies to evaluate MPs in mussels is presented. Then, an effective method to extract and characterize them in Mytilus Galloprovincialis is proposed. Six digestion procedures were studied: two 1-step alkaline-oxidative methods, two 2-steps alkaline-oxidative methods, a surfactant-oxidative method, and an enzymatic-oxidative one. The latter demonstrated the highest efficacy (recoveries >90 % for the tested polymers), though a modified 2-steps alkaline oxidation using a surfactant offers a cost-effective and slightly faster alternative (on average, 12–13 days, vs 16–17 days of the enzymatic one). The methods proposed here include a transfer protocol from stainless-steel to gold-coated filters (ca. 30 min per filter), which are then analyzed using a quantum cascade laser-based infrared imaging system, QCL-LDIR. The method was validated and its performance compared to previous works. Finally, the methodology was employed to measure MPs in both commercial (2.6 MPs/g, wet weight) and wild mussels (5.2 MPs/g, wet weight), demonstrating its applicability. • Six digestion procedures for mussels were studied before LDIR characterization. • Enzymatic digestion yielded best recoveries. • There are alkaline-oxidative alternatives that may compete in cost and speed. • Two transfer protocols of particles to gold-coated filters were compared • The impact of match indices on microplastics identification is discussed.
Source: Marine Pollution Bulletin
Institution: Universidade da Coruña
Language: English
Subfield: Pollution
Field: Environmental Science
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $3,740
OpenAlex ID: W4414397302