Science of the Total Environment, 2023,https://doi: 10.1016/j.scitotenv.2023.166113  

Abstract

Guvermectin is a novel biopesticide often used as seed soaking to promote the rice yield. However, its biotoxicity and degradation behavior in soils were still not disclosed, which posed a knowledge gap to guide its rational application. Therefore, the degradation behaviors of guvermectin in four typical soils under aerobic and anaerobic conditions were investigated in the laboratory. The results showed that guvermectin was degraded fast with DT₅₀ ranging from 0.95 to 10.10 d, and the degradation rate was higher in aerobic condition than that in anaerobic condition. Eight transformation products were screened using UPLC-QTOF/MS. The acute toxicities tests of guvermectin to  Coturnix coturnix japo  nica   and   Apis mellifera  were measured by biological laboratory experiments, and the acute and chronic toxicities of transformation products to  Danio rerio ,  Daphnia magna Straus and Green algae were predicted by ECOSAR software. The results showed that guvermectin has low toxic to quail and honeybee (LD₅₀2000 mg a.i./kg body weight, LD₅₀˃100 μg a.i./bee), and its transformation products were also low toxic class to  Danio rerio, Daphnia magna  Straus and  Green algae  (LC₅₀/EC₅₀> 100 mg a.i./L). However, the nucleoside-like metabolites may pose a potential risk due to their similarity to genetic material, which should be concerned. The findings provided important environmental risk assessment data for the rational use of guvermectin.

Science of the Total Environment,IF=9.8

https://pubmed.ncbi.nlm.nih.gov/37572911/