Atmospheric Cold Plasma Degradation of Fenvalerate Residues on Shiitake Mushrooms: Mechanisms, Toxicity Evolution, and Quality Effects

Fenvalerate residues on edible mushrooms pose significant risks to food safety and aquatic ecosystems. This study investigated the efficiency, degradation mechanisms, toxicity evolution, and quality effects of atmospheric cold plasma (ACP) for removing fenvalerate from shiitake mushrooms. Fenvalerate degradation increased with ACP treatment voltage and exposure time, reaching a maximum efficiency of 82.5% at 80 kV for 15 min. Quantum chemical calculations based on Fukui functions and frontier molecular orbitals identified phenoxy and chlorophenyl moieties as primary reactive sites. High-performance liquid chromatography–tandem mass spectrometry revealed degradation pathways dominated by hydroxylation, ester bond cleavage, and oxidative transformations. Toxicity assessment using ECOSAR predictions and yeast bioassays demonstrated substantial reductions in acute and chronic toxicity by ACP treatment, although some intermediates retained residual toxicity. In addition, ACP preserved mushroom quality during refrigerated storage. Overall, ACP represents a promising non-thermal strategy for pesticide detoxification while preserving edible mushroom quality.