The toxicity and teratogenicity of gibberellic acid (GA3) based on the frog embryo teratogenesis assay-Xenopus (FETAX)

Abstract

This study investigated the developmental toxicity of a plant growth regulator (a type of pesticide) using the frog embryo teratogenesis assay-Xenopus (FETAX). Xenopus laevis embryos were exposed to 11 different concentrations of gibberellic acid (GA_3), from stage 8 to 11, for 96 h under static renewal test conditions. The median lethal concentration (LC_{50}), malformation (EC_{50}), non-observed adverse effect concentration (NOAEC), and lowest observed adverse effect concentration (LOAEC) were calculated. The corresponding LC_{50} and EC_{50} values determined for GA3 exposure were 1117.5 mg/L and 658 mg/L, respectively. The TI (LC50/EC50) value calculated for GA_3 was 1.69. Different anomalies occurred in the embryos, depending on the GA_3 concentration. Based on these results, we conclude that GA_3 is toxic and teratogenic to Xenopus laevis embryos. Moreover, our results confirm that the FETAX assay can be a useful pretest for integrated biological hazard assessment of chemical agents used in agriculture.