Gold Nanoparticles Pile Up in Tadpoles When Aquatic Plants Share the Water

Gold nanoparticles, increasingly used in industrial and biomedical applications, may behave differently in freshwater systems when aquatic vegetation is present than single-species tests suggest. A study published in Ecotoxicology reports that larvae of the toad Rhinella arenarum accumulated markedly more gold when they shared their water with the aquatic plant Lemna minor than when they were exposed to the nanoparticles alone. The plants themselves also accumulated gold under every exposure condition tested, pointing to a role for aquatic vegetation in nanoparticle dynamics in freshwater systems.

The research team, which included Gabriela Svartz, Elizabeth Acosta, María Jazmín Penelas and Emmanuel de la Fournière, ran three sets of 96-hour laboratory bioassays. In the first, tadpoles and plants were exposed individually to gold nanoparticles at concentrations of 1 and 10 milligrams per litre. In the second, larvae and plants were exposed simultaneously.

In the third, larvae were placed in clean water with plants that had already been contaminated, testing whether the metal could move through a simple plant-to-larvae route. Gold concentrations were quantified in both organisms, and accumulation factors were calculated. The simultaneous-exposure results were the most striking.

Accumulation factors in the larvae reached 6,666 ± 1,020 litres per kilogram at 1 milligram per litre and 10,089 ± 760 litres per kilogram at 10 milligrams per litre, markedly higher than in the individual-exposure trials. The authors interpret this pattern as evidence that the presence of aquatic vegetation enhances the availability of the nanoparticles to the amphibians. Trophic transfer also occurred, but less efficiently.

Tadpoles that encountered gold only by ingesting previously contaminated plants still accumulated the metal, although at lower levels than larvae exposed directly in the water. This indicates that a dietary route from plants can contribute to nanoparticle accumulation in tadpoles even when the surrounding medium is clean, but that direct aqueous exposure transfers the particles more effectively. Lemna minor took up gold under both isolated and simultaneous exposure conditions, confirming the authors' description of aquatic plants as nanoparticle reservoirs in aquatic systems.

The study was conducted in laboratory bioassays over a 96-hour window at two nanoparticle concentrations, so the findings reflect short-term uptake under controlled conditions rather than effects on survival, development or wild populations; the measured endpoints concern gold accumulation and transfer only, and no toxic outcomes are reported. Gold nanoparticles are increasingly used in industrial and biomedical applications, raising concerns about their release into aquatic environments and their potential effects on non-target organisms. Within that context, the results demonstrate that aquatic vegetation can significantly modulate nanoparticle transfer and availability in freshwater amphibians.

Subject of Research: Accumulation and trophic transfer of gold nanoparticles in amphibian larvae and the aquatic plant Lemna minor under direct and plant-mediated exposure scenarios

Article Title: Gold nanoparticle accumulation in amphibian larvae under direct and plant-mediated exposure scenarios

Article References: Svartz, G., Acosta, E., Penelas, M. J., & de la Fournière, E. (2026). Gold nanoparticle accumulation in amphibian larvae under direct and plant-mediated exposure scenarios. Ecotoxicology, 35(9), Article 195. https://doi.org/10.1007/s10646-026-03185-7

Image Credits: AI Generated

DOI: 10.1007/s10646-026-03185-7

Keywords: gold nanoparticles, Rhinella arenarum, Lemna minor, ecotoxicology, amphibian larvae, trophic transfer, freshwater, bioaccumulation, nanomaterials, aquatic plants, Gold, nanoparticle