The Trojan horse effect of nanoplastics exacerbates methylmercury-induced neurotoxicity during zebrafish development.

While the ability of plastic particles to transport heavy metals is well established, their Trojan horse effect on aquatic organisms remains debated, as they are suspected of facilitating the penetration of chemicals in tissues but also of reducing bioavailability and accelerating pollutant elimination. Here, we investigated the combined effects of 250 nm polystyrene nanoplastics (NPs) and methylmercury (MeHg) on zebrafish larvae over a 30-day exposure period. Larvae were exposed to 1000 μg/L NPs, 1 μg/L MeHg (MeHg1), 10 μg/L MeHg (MeHg10), or their respective combinations (Mix1 and Mix10).

Disrupted senses and social cues: Impacts of nanoplastics and methylmercury on zebrafish neurodevelopment.

With the advancement of analytical techniques and the global increase in plastic pollution, nanoplastics (NPs) have been increasingly detected across all ecosystems and in deep tissues, including the human brain. Notably, NPs are capable of acting as vectors for co-contaminants such as heavy metals, raising concerns about their combined toxicity. In this study, zebrafish (Danio rerio) were exposed to 250 nm polystyrene NPs (1000 µg/L), either alone or in combination with 10 µg/L of methylmercury (MeHg), during the first 30 days of development.

Down to size: Exploring the influence of plastic particle Dimensions on physiological and nervous responses in early-stage zebrafish.

The chorion is the first protective barrier set to prevent numerous pollutants from damaging the developing embryo. However, depending on their size, some nanoplastics (NPs) can pass through this barrier and reach the embryo, while all microplastics (MPs) remain on the outside. This study brings a straight approach to compare MPs and NPs, and assess their direct and indirect effects on zebrafish embryos and larvae.