Hazardous fipronil insecticide effects on aquatic animals' health: Historical review and trends

Abstract

Fipronil (FIP) is a broad-spectrum and highly efficient insecticide used against several arthropod pests, such as parasitic mites and insect pests affecting both animals and plants. Given its several benefits, FIP is widely used in the agricultural and veterinary medicine fields, but its indiscriminate use can have ecotoxic effects on non-target species. Thus, the current study aimed to summarise and critically analyse FIP's ecotoxicity in aquatic animals. Data referring to bibliometric parameters (publication year and geographical distribution), experimental conditions (field and laboratory, FIP type, animal class, species, habitat, and exposure conditions), and biomarkers (oxidative stress, DNA damage, neurotoxicity, and morphological changes) were summarised and critically analysed. Ecotoxicological studies were mainly conducted with insects, crustaceans, molluscs, and fish. Exposure to pure FIP or FIP-based commercial formulation can induce mortality and have sublethal effects on non-target organisms, such as increased reactive oxygen species (ROS), oxidative damage, genotoxicity (DNA damage), neurotoxicity, and morphological changes. The herein reviewed data have evidenced high median lethal FIP concentration (LC₅₀) in vertebrates in comparison to invertebrates. The current findings confirmed that FIP can have several effects on aquatic organisms, besides suggesting potential ecotoxicological risks posed by this insecticide.

Keywords: Aquatic toxicology; Biomarkers; Ecotoxicity; Insecticide; Pesticide; Phenylpyrazoles.