Chitinase digestion for the analysis of microplastics in chitinaceous organisms using the terrestrial isopod Oniscus asellus L. as a model organism

Chitinaceous organisms have been found to ingest microplastic; however, a standardised, validated, and time- cost-efficient method for dissolving these without affecting microplastic particles is still required. This study tested four protocols with chitin exoskeleton: 1) potassium hydroxide (KOH) + chitinase, 2) Creon® 3) hydrogen peroxide (H2O2) and, 4) Nitric Acid (HNO3) (H2O2). The effects on microplastics composed of eight different polymers were also tested. use H2O2 followed by chitinase was be highly efficient method. three other either did not digest the sufficiently or negatively affected polymers. A recovery test using fibres, beads tyre revealed high rates 0.85, 0.89 1 respectively. further supported applicability (protocol chitinaceous organisms. Thus, we recommend that future investigations (0.05 μm–5000 μm) in (0.3 cm–5 cm) utilise here presented methodology. represents an important component ongoing validation harmonization methodological approaches are urgently needed advancement assessments globally.