Improved Raman spectroscopy-based approach to assess microplastics in seafood. (15th November 2021)

• Record Type: Journal Article
• Authors: Leung, Matthew Ming-Lok; Ho, Yuen-Wa; Lee, Cheng-Hao; Wang, Youji; Hu, Menghong; Kwok, Kevin Wing Hin; Chua, Song-Lin; Fang, James Kar-Hei
• Is Part Of: Environmental pollution. Volume 289(2021)
• Publication Date: 2021-11-15
• Subjects: Fish -- Mussels -- Raman mapping -- Autofluorescence -- Food contamination; Pollution -- Periodicals; Pollution -- Environmental aspects -- Periodicals; Environmental Pollution -- Periodicals; Pollution -- Périodiques; Pollution -- Aspect de l'environnement -- Périodiques; Pollution -- Effets physiologiques -- Périodiques; Pollution; Pollution -- Environmental aspects; Periodicals; Electronic journals; 363.73
• DOI: 10.1016/j.envpol.2021.117648
• Languages: English
• ISSNs: 0269-7491

Abstract

Abstract: Microplastics represent an emerging environmental issue and have been found almost everywhere including seafood, raising a great concern about the ecological and human health risks they pose. This study addressed the common technical challenges in the assessment of microplastics in seafood by developing an improved protocol based on Raman spectroscopy and using the green-lipped mussel Perna viridis and the Japanese jack mackerel Trachurus japonicus as the test models. Our findings identified a type of stainless-steel filter membranes with minimal Raman interference, and a combination of chemicals that achieved 99–100% digestion efficiency for both organic and inorganic biomass. This combined chemical treatment reached 90–100% recovery rates for seven types of microplastics, on which the surface modification was considered negligible and did not affect the accuracy of polymer identification based on Raman spectra, which showed 94–99% similarity to corresponding untreated microplastics. The developed extraction method for microplastics was further combined with an automated Raman mapping approach, from which our results confirmed the presence of microplastics in P. viridis and T. japonicus collected from Hong Kong waters. Identified microplastics included polypropylene, polyethylene, polystyrene and poly(ethylene terephthalate), mainly in the form of fragments and fibres. Our protocol is applicable to other biological samples, and provides an improved alternative to streamline the workflow of microplastic analysis for routine monitoring purposes. Graphical abstract: Image 1 Highlights: An improved method to extract microplastics from organic and inorganic biomass. An automated mapping approach to characterise the extracted microplastics. The protocol for seafood also applicable to other biological samples.