Preliminary investigation of microplastic contamination in river snails (<i>Filopaludina martensi</i>) in Eastern Thailand and evaluation of human exposure

Microplastic contamination in the aquatic environment is a growing environmental issue with implications for food safety concerns. This study investigated microplastics in river snails ( Filopaludina martensi ) obtained from local markets in the eastern province of Thailand. The study analyzed the abundance, shape, size, color, and polymer type of microplastics extracted from river snail tissue and estimated human intake of microplastics through river snail consumption. The results revealed that the average microplastic abundance was 88.63 ± 51.18 particles/g wet weight. The predominant microplastics were fibers and fragments smaller than 1.0 mm, with colors ranging from transparent-white. Polymer analysis indicated that river snails primarily contained polyethylene (PE), polypropylene (PP), and polystyrene (PS). Microplastics’ estimated annual intake (EAI) was significantly higher than the average in other countries. This suggests that humans may ingest microplastics through food consumption due to the biomagnification of microplastic accumulation in the food chain. Given this elevated level of human exposure to microplastics, there is an urgent need to develop policies to regulate the use, management, and disposal of plastic waste in Thailand.