Acrylamide Impacts on Black Soldier Fly Larvae: Growth, Toxicity, Microbes, and Bioaccumulation Risks for Food/Feed Safety.

Abstract

This study investigated the effects of acrylamide on the growth, neurobehavioral responses, gut integrity, microbial composition, and toxicokinetics of black soldier fly larvae (BSFL). Larvae were exposed to acrylamide-contaminated diets at 0.05, 0.5, and 5 mg/kg (dry weight) to assess dose-dependent impacts. Results revealed that acrylamide exposure delayed larval growth peaks and reduced maximum weights by 6.17-76.01% (12-18 days). Additionally, crawling speed decreased significantly at ≥0.5 mg/kg, indicating neurotoxicity. Trypan blue staining demonstrated dose-dependent midgut damage (2.22% in control vs. 25.56% at 5 mg/kg), correlating with compromised nutrient absorption. Gut microbiota analysis showed enrichment of pathogenic genera (e.g., Escherichia-Shigella) and suppression of beneficial taxa (e.g., Klebsiella), alongside reduced metabolic and immune-related pathways via Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis. Toxicokinetic modeling revealed bioaccumulation, with bioaccumulation factors (BAF) inversely related to substrate concentration (18.67 at 0.05 mg/kg vs. 2.90 at 5 mg/kg). Elimination half-lives (DT₅₀) varied from 3.25 to 8.22 days, suggesting concentration-dependent detoxification efficiency. These findings highlight acrylamide's multifaceted toxicity in BSFL, emphasizing risks in waste valorization and insect-based feed production. This study underscores the need for substrate safety protocols to ensure sustainable applications of BSFL in the circular bioeconomy.