“Biochemical impacts of polyethylene terephthalate microplastics and cadmium on Danio rerio under environmental conditions”

Morales-Espinoza L.L.; Ferreira M.T.; Santos Carvalho C.D.; Frighetto P.D.; Moraes Utsunomiya H.S.; Morales-Paredes L.F.; Fracácio R. · Ecotoxicology (2026) · DOI: 10.1007/s10646-025-02987-5

Resumen

The escalating presence of microplastics (MPs) in aquatic ecosystems has sparked significant concern due to their detrimental effects on biota. A current debate revolves around the potential influence of type, size, and co-exposure with other contaminants on the toxicity of MPs. Here, two 21-day experiments with adult Danio rerio were carried out to verify the effects of different particle sizes of polyethylene terephthalate (PET-MPs) (300–425 μm and 53–75 μm), at two different environmentally relevant concentrations: 983 particles. L− 1 and 330 particles. L− 1, and to demonstrate the possible effects of Cd (10 µg. L− 1), 53 μm PET-MP (330 particles. L− 1) and their mixture (PET-MP + Cd), on a set of biochemical indicators: total proteins, carbonylated protein (CP), glucose, triglycerides, lactate dehydrogenase (LDH) and malate dehydrogenase (MDH) activity. During exposure, there was no mortality. For the largest size (300–425 μm) there was a significant increase in CP levels, and a decrease in glucose and LDH levels compared to the control in both concentrations. In the experiment with PET-MPs co-exposed to Cd, the CP levels showed a significant increase in the PET-MP + Cd group compared to the control and PET-MP alone, evidence of oxidative stress due to the addition of Cd. LDH levels decreased significantly when Cd was added to the PET-MP. MDH of the Cd group showed a significant increase when compared to the control group and PET-MP alone. Our study demonstrated that the toxicity of PET-MPs varied depending on the size, concentration, and combination with Cd. © The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2025.

Instituciones: Universidad Nacional de San Agustín de Arequipa