Modeling the Bioconcentration of Microplastics in Nile Tilapia (Oreochromis niloticus) under Variable Stocking Densities and Filtration Regimes

Abstract

Microplastic contamination in aquaculture systems is an emerging concern due to its potential impact on fish health and food safety. This study evaluates the bioconcentration of microplastics in Nile tilapia (Oreochromis niloticus) under varying stocking densities and filtration regimes to understand management influences on contaminant accumulation. Controlled aquaculture experiments were conducted using different combinations of stocking densities and water filtration systems to assess their effects on microplastic exposure and uptake. Key parameters measured included microplastic concentration in water, accumulation in fish tissues, growth performance, feed utilization, and physiological stress indicators. Results indicated that higher stocking densities increased microplastic accumulation in fish due to greater particle resuspension and ingestion rates, while efficient filtration systems significantly reduced microplastic concentrations in the culture environment. Fish reared under optimized filtration conditions exhibited lower levels of microplastic accumulation and better growth performance compared to those in poorly filtered systems. The study also observed that prolonged exposure led to gradual accumulation in digestive and tissue compartments, highlighting potential risks for food safety. The findings emphasize the importance of water quality management and system design in minimizing microplastic contamination in aquaculture. While modeling approaches were used to analyze accumulation patterns, the primary focus remains on aquaculture management and fish health. These results provide practical insights for fish farmers to optimize stocking densities and filtration practices, reduce contaminant exposure, and ensure sustainable and safe production of Nile tilapia in aquaculture systems.a