Do Perfluorinated Chemicals Enhance the Toxicity of Other Contaminants in Aquatic Organisms?

Environmental contaminants pose threats to various organisms and negatively impact the nervous, cardiovascular, immune, and reproductive systems. Per- and polyfluoroalkyl substances (PFAS) are synthetic chemicals that are ubiquitous in the environment. Given that mixtures of environmental contaminants have the potential to exacerbate toxicity, we reviewed current literature on pesticides, microplastics, or metal exposure in combination with PFAS on vertebrates and invertebrates. The objectives were to evaluate the toxicological effects of mixtures of different pollutants (microplastics, pesticides and metal ions) with PFAS on aquatic organisms to better understand biological responses in animals. Based on our review, an increase in toxicity is observed in mixtures of pollutants, including enhanced oxidative stress, developmental abnormalities, impaired reproduction, metabolic disruption, altered gene expression, and changes in enzymatic activity; however, some antagonistic interactions were also reported, underscoring the complexity of mixture effects in real environments. A computational assessment demonstrates that PFOS can engage in intermolecular interactions with pesticides, microplastic monomers, and metals, suggesting chemical-level mechanisms that could modify toxicity or bioavailability. Future studies should focus on elucidating the mechanisms underlying these complex interactions, investigating effects at different trophic levels and in a broader range of species, including mammalian models, and considering chronic exposures and environmentally relevant mixtures.