Metaflumizone is a new insecticide developed for crop protection and urban pest control by BASF. Its mammalian toxicological profile was assessed by conducting multiple toxicity studies in the rat, mouse, and dog, covering all relevant endpoints. Metaflumizone is characterized by very low acute toxicity, is not irritating to the eye or the skin and does not possess a potential to induce skin sensitization. The substance also shows relatively low toxicity following subchronic oral or dermal exposure to mammals. In addition, metaflumizone demonstrates low toxicological potential following chronic oral exposure to rats, mice, and dogs. Overall, the lowest no observed adverse effect level (NOAEL) is 12mg/(kgday) from the 1-year chronic dog study. In a battery of in vitro and in vivo mutagenicity assays, the weight-of-the-evidence indicates a lack of potential genotoxicity for metaflumizone. Furthermore, the compound demonstrated a lack of potential oncogenicity in long-term toxicity studies in rats and mice. Results from the rat multi-generation reproductive toxicity study as well as the rat and rabbit developmental toxicity studies indicate that metaflumizone is not selectively toxic to the offspring or fetus, as compared to the parents. Also, metaflumizone is not teratogenic in the rat or rabbit. Lastly, no neurotoxicity could be detected in acute and subchronic neurotoxicity studies in rats.