Degradation Dynamics and Residue Analysis of Flubendiamide in Cabbage and Soil by Liquid Chromatography-Tandem Mass Spectrometry with Dispersive Solid Phase Extraction

To formulate a scientific basis for a reasonable spray dose and safe interval period of 20% flubendiamide water dispersible granule (WDG) on controlling vegetable pests, degradation dynamics of flubendiamide in cabbage and soil was analyzed in this study. Dissipation and residue of flubendiamide in 20% flubendiamide WDG in cabbage and soil under field conditions were investigated by liquid chromatography-tandem mass spectrometry with dispersive solid phase extraction. Results showed that the degradation dynamic equations of flubendiamide in cabbage and soil were based on the first-order reaction dynamic equations. The half-lives of the degradation of flubendiamide were 3.51 d to 3.96 d and 3.43 d to 3.87 d in the cabbage of Yangzhou and Jingzhou, respectively, and 4.42 d to 5.13 d and 4.37 d to 4.99 d in the soil of Yangzhou and Jingzhou, respectively. The terminal residues of flubendiamide in the cabbage of Yangzhou and Jingzhou were 0.0247 mg·kg-1 to 0.0393 mg·kg-1 and 0.0225 mg·kg-1 to 0.0273 mg·kg-1, respectively, when 20% flubendiamide WDG was applied at a dose of0.050g·m-2. Flubendiamide is safe to be applied in cabbage fields at the recommended dose.

Pre-mating nitenpyram exposure in male mice leads to depression-like behavior in offspring by affecting tryptophan metabolism in gut microbiota

Several studies have confirmed that the health status of the paternal affects the health of the offspring,however,it remains unknown whether paternal exposure to pesticides affect the offspring health.Here,we used untargeted metabolomics and 16S rRNA sequencing technology,combined with tail suspension test and RT-qPCR to explore the effects of paternal exposure to nitenpyram on the neurotoxicity of offspring.Our results found that the paternal exposure to nitenpyram led to the offspring’s depressive-like behaviors,accompanied by the reduction of tryptophan content and the disorder of microbial abundance in the gut of the offspring.Further,we determined the expression of tryptophan metabolism-related genes tryptophanase(tnaA)and tryptophan hydroxylase 1(TpH1)in gut bacteria and colonic tissues.We found that tryptophan is metabolized to indoles rather than being absorbed into colonocytes,which coursed the reduce of tryptophan availability after nitenpyram exposure.In conclusion,our study deepens our understanding of the intergenerational toxic effects of pesticides.