Toxicity of spirotetramat and oxidative stress response in female zebrafish(Danio rerio)

In order to evaluate the aquatic toxicity of spirotetramat, a new tetramic acid derivative, the acute toxicity and oxidative stress of spirotetramat in female zebrafish(Danio rerio) was studied. The result of acute toxicity test showed that the 96 h-LC50 value of spirotetramat was 7.21 mg/L, suggesting spirotetramat has moderate toxicity to female zebrafish. Oxidative stress was processed by assaying antioxidant enzyme activities(CAT, Cu/Zn-SOD, Mn-SOD and GSH-Px), relative mRNA expression levels of genes(Cat, Cu/Zn-Sod, Mn-Sod, Gpx) and MDA content in zebrafish muscle after exposing to various mass concentrations(0, 36, 360 and 1 800 μg/L) of spirotetramat for 28 d. The results indicated that spirotetramat could induce significant increase of the CAT and GSH-Px activities, MDA content, and mRNA expression levels of Cat, Mn-Sod and Gpx in zebrafish muscle; while the Cu/Zn-Sod mRNA expression level and Cu/Zn-SOD activity was not changed significantly. The results suggested that oxidative stress was induced in zebrafish muscle by spirotetramat, which may cause oxidative damage in the fish.