Determining Maximum Allowable Concentrations of Selenium and Iron Nanoparticles in Hediste diversicolor as Sturgeon Live Feed

ABSTRACT: This study aimed to determine the acute dietary toxicity and Maximum Allowable Concentration (MAC) of selenium (Se-NPs) and iron (Fe-NPs) nanoparticles for the ragworm (Hediste diversicolor). This worm is a critical live feed source in sturgeon aquaculture, directly influencing the health and growth of larvae and juveniles. However, the safe dietary levels of these nanoparticles for the ragworm itself, and consequently the risk of trophic transfer to sturgeon, remain unknown. Determining safe dietary levels of nanoparticles in this organism is therefore essential for ensuring the safety of the entire sturgeon feed chain. Worms were exposed to six concentrations (0, 100 μg/kg, 1, 10, 100 mg/kg, and 1 g/kg diet) of each nanoparticle for 96 h in three replicates. Throughout the experiment, aeration was provided, and worm behavior was monitored. Cumulative mortality was recorded at 24, 48, 72, and 96-h intervals. Data were recorded in Microsoft Office Excel 2019, and statistical analysis was performed using SPSS software (Version 26). Data were analyzed by Probit analysis with a 95% confidence level. The LC₁₀, LC₅₀, and LC₉₀ values for Se-NPs were calculated to be 291.2, 989.8, and 1690 mg/kg, respectively. For Fe-NPs, these values were 924.3, 3300, and 5700 mg/kg, respectively. Using a standard Safety Factor (SF) of 10, the calculated MAC are 98.98 mg/kg for Se-NPs and 330.0 mg/kg for Fe-NPs. This study establishes critical toxicity thresholds for Se-NPs and Fe-NPs in ragworm. The findings provide essential data for developing safe feeding protocols in sturgeon aquaculture, helping to prevent potential nanoparticle toxicity transfer through contaminated live feed and ensuring sustainable sturgeon production.