In vitro acute cytotoxicity of the neonicotinoid insecticide acetamiprid to FG cells, the gill cell line of flounder Paralichthy olivaceus

The in vitro acute cytotoxicity of the neonicotinoid insecticide acetamiprid to FG cell line, derived from the gill of flounder Paralichthys olivaceus, was tested by the three widely used endpoint bioassays-neutral red (NR) assay, tetrazolium (MTT) assay and cell protein assay.It was found that acetamiprid was increasingly toxic to FG cells at concentrations of 1 μg/cm³ or above, and the inhibitory concentration 50% values for NR, MTT, and cell protein assays were 38.38, 36.27 and 32.03 μg/cm³, respectively.This appeared to be the first report on the in vitro cytotoxicity of acetamiprid to non-mammalian vertebrate cells.Ultrastructural examination revealed that for the cells exposed to 60 μg/cm³ acetamiprid for 48 h, their mitochondria were severely damaged with the cristae swelled up or disrupted, while their nuclei and rough endoplasmic reticlum (RER) appeared to be still normal.This suggests that mitochondria are possibly the primary target of acetamiprid.