We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Microplastics and TiO2 nanoparticles mixture as an emerging threat to amphibians: A case study on bullfrog embryos
Summary
Scientists studied the combined effects of polyethylene microplastics and titanium dioxide nanoparticles on bullfrog embryo development. While the microplastics alone did not significantly harm the embryos because they stuck to the outer protective layer, the nanoparticles reduced survival and hatching rates. This study shows that different types of tiny particles can interact in complex ways in the environment, and that amphibian embryos may be more vulnerable to nanoparticles than to microplastics during early development.
Emerging contaminants can act as contributing factors to the decline of amphibian populations worldwide. Recently, scientists have drawn attention to the potential ecotoxicity of microplastics and nanomaterials in amphibians, however, their possible effects on embryonic developmental stages are still absent. Thus, the present study analyzed the developmental toxicity of environmentally relevant concentrations of polyethylene microplastics (PE MPs; 60 mg/L) and titanium dioxide nanoparticles (TiO2 NPs; 10 μg/L), isolated or in combination (Mix group) on bullfrog embryos, Aquarana catesbeiana, adapting the Frog Embryo Teratogenesis Assay (FETAX, 96h). Allied to the FETAX protocol, we also analyzed the heart rate and morphometric data. The exposure reduced the survival and hatching rates in groups exposed to TiO2 NPs, and to a lesser extent, also affected the Mix group. TiO2 NPs possibly interacted with the hatching enzymes of the embryos, preventing hatching, and reducing their survival. The reduced effects in the Mix group are due to the agglomeration of both toxicants, making the NPs less available for the embryos. PE MPs got attached to the gelatinous capsule of the chorion (confirmed by fluorescence microscopy), which protected the embryos from eventual direct effects of the microplastics on the hatching and survival rates. Although there were no cardiotoxic effects nor morphometric alterations, there was a significant increase in abdominal edemas in the hatched embryos of the PE MPs group, which indicates that osmoregulation might have been affected by the attachment of the microplastics on the embryos' gelatinous capsule. This study presents the first evidence of developmental toxicity of environmental mixtures of microplastics and nanoparticles on amphibians and reinforces the need for more studies with other amphibian species, especially neotropical specimens that could present bigger sensibility. Our study also highlighted several features of the FETAX protocol as useful tools to evaluate the embryotoxicity of several pollutants on amphibians.
Sign in to start a discussion.
More Papers Like This
Genotoxicity, mutagenicity and immunotoxicity assessment of microplastics and nanoparticle mixture in bullfrog tadpoles
Researchers exposed bullfrog tadpoles to polyethylene microplastics and titanium dioxide nanoparticles, both individually and in combination, for 15 days to assess genetic damage and immune effects. While the pollutants did not cause direct DNA damage at the tested concentrations, the microplastics alone and in combination with nanoparticles triggered changes in immune cell composition. The study suggests that even at relatively low concentrations, microplastics can alter immune function in amphibians, which are among the most threatened vertebrate groups worldwide.
Ecotoxicity of polyethylene microplastics and titanium dioxide nanoparticles, isolated and combined, in the gills and livers of Aquarana catesbeiana (Shaw, 1802) tadpoles.
Researchers assessed the combined ecotoxicity of polyethylene microplastics and titanium dioxide nanoparticles on aquatic organisms, testing both contaminants individually and in combination to evaluate whether co-exposure produces additive, synergistic, or antagonistic toxic effects.
Toxicity assessment of polyethylene microplastics in combination with a mix of emerging pollutants on Physalaemus cuvieri tadpoles
Researchers assessed the toxicity of polyethylene microplastics alone and in combination with a mixture of emerging pollutants on tadpoles of the frog Physalaemus cuvieri over 30 days. They found that combined exposure produced more severe effects on biomarkers related to oxidative stress and morphological development than individual exposures. The study highlights the need to consider how microplastics interact with other environmental contaminants when evaluating risks to amphibian populations.
Microplastics and plastic additives as contaminants of emerging concern: A multi-biomarker approach using Rhinella arenarum tadpoles
Researchers exposed toad tadpoles to polyethylene microplastics and the flame retardant TBBPA, both alone and in combination, for 30 days. They found that the mixture produced different toxic effects than either substance alone, affecting growth, enzyme activity, and cellular stress markers. The study highlights the importance of studying microplastics alongside common plastic additives, since their combined effects may differ from individual exposures.
Developmental toxicity of co-exposure of heavy metal and polystyrene microplastics in Xenopus laevis embryo
Researchers exposed Xenopus laevis frog embryos simultaneously to cadmium, copper, lead, and polystyrene microbeads, finding that co-exposure produced more complex effects than any single contaminant and that interactions included antagonistic as well as additive outcomes.