High-throughput pesticide toxicity assessment in Black Soldier Fly (Hermetia illucens) by behavioral phenomics.

The increasing demand for efficient and ecologically relevant toxicity assessment methods has driven the exploration of alternative model organisms. Hermetia illucens, the Black Soldier Fly (BSF), has emerged as a promising candidate due to its rapid life cycle, high reproductive capacity, and adaptability to diverse environments. This study proposes BSF as a novel insect model for high-throughput chemical toxicity assessments, leveraging its locomotion activity as a sensitive and quantifiable endpoint. Preliminary results showed that BSF larvae exhibit more active locomotion than other insects, such as yellow mealworms, making them practical for detecting compromised movement caused by chemical exposure. Using a behavioral assay, BSF larvae were exposed to 30 different pesticides to assess their toxicity. Most pesticide-treated larvae displayed reduced locomotion activity. Moreover, these pesticides exerted a pronounced effect on other behavioral endpoints, including fractal dimension, entropy, and time spent in the center area. Among the tested compounds, fipronil produced the most severe effects on BSF larvae. RNAseq analysis was conducted to further investigate the mechanism underlying pesticide-induced impairment. Transcriptome profiling revealed broad transcriptional reprogramming in pesticide-treated BSF larvae, including impacts on mitochondrial energy metabolism, neuromuscular coordination disruption, and increased cuticle biosynthesis. Overall, BSF larvae demonstrated strong potential as an animal model for environmental toxicity assessment. Establishing BSF as a new insect model for chemical toxicity testing holds significant promise for advancing environmental monitoring, chemical safety evaluation, and sustainable toxicology research.