The chapter discusses the neurotoxic effects of various environmental pollutants on zebrafish, focusing on nanoplastics, microplastics, fipronil, deltamethrin, and rotenone. Zebrafish are used as model organisms due to their structural, functional, and material advantages, including a short reproductive cycle, high fecundity, and a transparent embryo stage, which allows for direct observation of developmental processes. The nervous system of zebrafish is similar to that of humans, making them ideal for studying neurotoxicity. Nanoplastics and microplastics are widespread in aquatic ecosystems, with nanoplastics being more reactive and toxic due to their larger surface area and ability to adsorb other contaminants. Studies have shown that exposure to nanoplastics can lead to neurobehavioral impairments, including altered exploration behavior, reduced anxiety, and increased hyperreactivity. Microplastics can also cause oxidative stress, leading to neuronal damage and behavioral changes such as impaired swimming ability and social interaction. Fipronil, an insecticide, disrupts chloride channels in insect cell membranes, leading to hyperexcitation of the central nervous system. It can also inhibit glycine receptors, causing muscle convulsions and respiratory muscle injury. Fipronil has been banned in Europe for agricultural use but remains relevant due to its use in veterinary treatments. The chapter highlights the importance of monitoring and controlling the effects of contaminants in the aquatic environment to protect human and animal health. It emphasizes the need for further research to understand the specific mechanisms by which these pollutants affect zebrafish and to develop effective mitigation strategies.The chapter discusses the neurotoxic effects of various environmental pollutants on zebrafish, focusing on nanoplastics, microplastics, fipronil, deltamethrin, and rotenone. Zebrafish are used as model organisms due to their structural, functional, and material advantages, including a short reproductive cycle, high fecundity, and a transparent embryo stage, which allows for direct observation of developmental processes. The nervous system of zebrafish is similar to that of humans, making them ideal for studying neurotoxicity. Nanoplastics and microplastics are widespread in aquatic ecosystems, with nanoplastics being more reactive and toxic due to their larger surface area and ability to adsorb other contaminants. Studies have shown that exposure to nanoplastics can lead to neurobehavioral impairments, including altered exploration behavior, reduced anxiety, and increased hyperreactivity. Microplastics can also cause oxidative stress, leading to neuronal damage and behavioral changes such as impaired swimming ability and social interaction. Fipronil, an insecticide, disrupts chloride channels in insect cell membranes, leading to hyperexcitation of the central nervous system. It can also inhibit glycine receptors, causing muscle convulsions and respiratory muscle injury. Fipronil has been banned in Europe for agricultural use but remains relevant due to its use in veterinary treatments. The chapter highlights the importance of monitoring and controlling the effects of contaminants in the aquatic environment to protect human and animal health. It emphasizes the need for further research to understand the specific mechanisms by which these pollutants affect zebrafish and to develop effective mitigation strategies.