This study assessed the distribution of microplastics (MPs) in the gills, intestines, and muscles of the common carp (Cyprinus carpio), one of main fish species consumed by humans living in the lower regions of the Han River in South Korea. In total, 891 MP particles were detected in 15 carps, with an average of 59.4 ± 45.5 particles/specimen, indicating severe MP contamination. The predominant MP form was fragment (86%), and the size range was 0.02–0.10 mm. Thirty MP particles were detected in the muscle samples (n = 10), primarily in sizes < 0.1 mm (89%). The most common types of polymers detected in this study were polyethylene (≥42%), polystyrene (≥20%), and polypropylene (≥19%), which were at the same level as the polymer ratio of domestic plastic production/use. No correlation was observed between the length of common carp and the number of MPs detected in different body tissues, indicating an abundance of MPs in the environment rather than by residue and accumulation. These findings contribute to the evaluation of the potential impact of edible fish on human health and emphasize the need to develop strategies to reduce MP contamination originating from various potential land sources.

Emerging contaminants (ECs) are anthropogenic and naturally occurring chemicals detected in various environmental matrices, including remote regions such as Antarctica. Adamussium colbecki, an Antarctic bivalve, is an excellent bioindicator for assessing contamination in polar marine ecosystems. However, its high protein (10-18%) and lipid (2-10%) content require an effective sample pre-treatment to minimise matrix interferences during contaminant analysis. In this study, an optimised QuEChERS extraction method was developed and validated to determine ECs in A. colbecki using high-performance liquid chromatography coupled with tandem mass spectrometry (HPLC-MS/MS). A multivariate experimental design approach was employed to improve analyte recovery (R%) and minimise matrix effect (ME%). Initially, a Plackett-Burman screening identified the most influential factors, which were subsequently optimised using a Doehlert design to construct quadratic models for response optimisation. The final method allowed to obtain acceptable recoveries (46-123%) and satisfactory matrix effects (62-103%) for 18 ECs, confirming its suitability for complex biological matrices. The optimised protocol was then applied to A. colbecki specimens collected during Antarctic campaigns in 2001, 2005, 2018, and 2019. Triclosan (TCS) was quantified in two samples and detected below the quantification limit in two others, while perfluorooctanoic acid (PFOA) and octyl-dimethyl p-aminobenzoic acid (OD-PABA) were identified at trace levels in 2005 samples. This study presents the first validated QuEChERS method for ECs analysis in A. colbecki, providing a reliable tool for long-term environmental monitoring and contamination assessment in the Antarctic marine ecosystem.