MICROPLASTICS INGESTION BY FRESHWATER FISH IN THE CHI RIVER, THAILAND

Microplastic pollution mainly emanates from terrestrial sources but studies of plastic contamination in freshwater ecosystems remain limited. Consumption of freshwater fish is widespread throughout all regions of Southeast Asia. Contamination of microplastics in fish is an important issue which leads to human health risk. Common freshwater fish in the Chi River, Thailand were caught by local fishermen and investigated for abundance, size, color and shape of microplastics. Eight fish species were investigated. Results showed that 72.9% of the collected fish were polluted with microplastics at mean abundance of 1.760.97 particles per fish and was no significant difference of abundance between species. Percentage occurrence of microplastics was highest in omnivorous fish Puntioplites proctozysron (86.7%) with the most common size of microplastics ingested by fish at over 0.5 mm (47.5%), of which 56.9% were blue color and 86.9% were fiber shaped. Results revealed that fishing nets and fish cages were major sources of microplastic contaminants in the Chi River.