Presence of microplastics in tilapia (Oreochromis niloticus) along the Iloilo River

Abstract

Microplastic pollution poses a significant threat to aquatic ecosystems, with potential consequences for biodiversity and human health. This study investigates the presence and characteristics of microplastics in tilapia (Oreochromis niloticus) inhabiting the Iloilo River, a vital watercourse in the Philippines. Samples were collected from three distinct sites along the river: Barangay Tap-oc, Barangay San Rafael, and Barangay Progreso. A total of 45 tilapia specimens were examined, and microplastics were isolated from the gill and gut tissues using chemical digestion and filtration techniques. The results revealed a high detection rate of microplastics, with 95.6% of the fish specimens containing these contaminants. A total of 132 microplastic particles were identified, with fibrous morphologies being the most prevalent (70.5%), followed by particles (22.7%) and pellets (6.8%). Blue microplastics constituted the dominant color (50.0%), succeeded by red (21.2%) and black (15.9%). Statistical analysis demonstrated significant variations in microplastic abundance across sampling locations, with Barangay Tap-oc exhibiting the highest contamination levels. These findings underscore the pervasive nature of microplastic pollution in the Iloilo River ecosystem and the potential risks it poses to aquatic life and human health.