science of the total environment, 2023,https://doi: 10.1016/j.scitotenv.2023.164541
abstract
in this study, environmental behavior and toxicity of cyflumetofen (cyf) enantiomers were evaluated comprehensively in a soil-earthworm system. in the earthworm ( eisenia foetida ), ( )-cyf was preferentially accumulated, and acute toxicity of rac -cyf was greater than that of ( )-cyf and (-)-cyf, indicating that the combination of cyf enantiomers increased the toxicity. as a measure of chronic toxicity, compared with (-)-cyf-treated earthworms, malondialdehyde accumulation was higher in ( )-cyf-treated earthworms, indicating a more severe oxidative stress response. in a dna comet plot, the trailing distance in the ( )-cyf treatment was 1.97 times greater than that in the (-)-cyf-treated, revealing more severe genotoxicity with ( )-cyf. however, (-)-cyf was more likely than ( )-cyf to activate the earthworm detoxification enzyme pathway. with ( )-cyf treatment, the number of differentially expressed genes (degs) involved in the pathogenic pathway increased significantly, whereas with (-)-cyf-treatment, more degs were involved in p450 and glutathione s-transferase (gst) detoxification metabolic pathways, including high expression of the genes chi-iii, gst-s-1 , and gst-alpha-5 . the main metabolites of the cyf enantiomers were a-2, a-12, b-1, ab-1, ab-7, and b-3, which exhibited potential ecotoxicity. in general, cyf was stereoselective in the soil-earthworm ecosystem, with ( )-cyf causing a higher genotoxicity risk than that of (-)-cyf. the study provides insight into the selective toxicity mechanisms of chiral cyf and contributes to a theoretical basis for risk assessment of low-risk pesticides.
science of the total environment,if=9.8
https://pubmed.ncbi.nlm.nih.gov/37263435/
