Simple SummaryThe pollution of air, soil, and sea has grown in recent decades at the same pace as human development. Climate changes add further damage to the ecosystems. Nowadays, pollutants that derive from the anthropization of the environment are indicated as “emerging pollutants”. Marine organisms, especially invertebrates, are used as model systems for ecotoxicological studies also regarding the nervous system, even if studies on pollutants’ neurotoxic effects are still few. A great leap forward in knowledge can come from integrated omics studies that bring together genomics, transcriptomics, proteomics, and metabolomics data. These studies have revealed that pollutants are dangerous for the life of marine organisms, and not only because they can be modified in the environment, but also because they can combine giving rise to new mixtures. These new combinations can be even more harmful than individual pollutants. We must not forget that many marine organisms, both invertebrates and vertebrates, become part of the human food chain. Therefore, ultimately, the pollutants that contaminate the air, soil, and sea are potentially harmful to human health. The purpose of this review is to focus on some of the pollutants that are most frequently present in marine environments and analyze their neurotoxic potential effects on some marine model organisms.Invertebrates represent about 95% of existing species, and most of them belong to aquatic ecosystems. Marine invertebrates are found at intermediate levels of the food chain and, therefore, they play a central role in the biodiversity of ecosystems. Furthermore, these organisms have a short life cycle, easy laboratory manipulation, and high sensitivity to marine pollution and, therefore, they are considered to be optimal bioindicators for assessing detrimental chemical agents that are related to the marine environment and with potential toxicity to human health, including neurotoxicity. In general, albeit simple, the nervous system of marine invertebrates is composed of neuronal and glial cells, and it exhibits biochemical and functional similarities with the vertebrate nervous system, including humans. In recent decades, new genetic and transcriptomic technologies have made the identification of many neural genes and transcription factors homologous to those in humans possible. Neuroinflammation, oxidative stress, and altered levels of neurotransmitters are some of the aspects of neurotoxic effects that can also occur in marine invertebrate organisms. The purpose of this review is to provide an overview of major marine pollutants, such as heavy metals, pesticides, and micro and nano-plastics, with a focus on their neurotoxic effects in marine invertebrate organisms. This review could be a stimulus to bio-research towards the use of invertebrate model systems other than traditional, ethically questionable, time-consuming, and highly expensive mammalian models.
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