Combined effects of polymethylmethacrylate microplastics with arsenic and copper on the euryhaline rotifer Proales similis.

Aquatic organisms are typically exposed to chemical mixtures, including microplastics and metal(loid)s. However, most research has primarily focused on the toxicity of individual chemicals, potentially overestimating their risks to aquatic life. This study examined the combined effects of polymethylmethacrylate microplastics (PMMA-MPs) with As and Cu at environmentally relevant concentrations on the euryhaline rotifer Proales similis.

Effects of the insecticide chlorpyrifos on Amazonian freshwater invertebrates: A mesocosm experiment.

Chlorpyrifos is one of the most widely used insecticides globally, yet its toxicity for tropical aquatic ecosystems in Latin America has not been thoroughly evaluated. In this study, we conducted a 70-day mesocosm experiment to assess the effects of chlorpyrifos on zooplankton and macroinvertebrate communities representative of the Ecuadorian Amazon. Mesocosms were exposed to a single application of chlorpyrifos at four nominal concentrations (0.

Microplastic occurrence and distribution in the Gulf of Guayaquil, Ecuador.

Microplastics (MPs) were assessed in water and sediment samples along the Salado Estuary, an estuarine system composed of a complex river drainage network in Guayas, Ecuador. MPs were quantified and categorized according to shape, size, and composition. Pellet morphology (237,490 MP/L) and transparent color MPs (252,990 MP/L) were the most common in water, while fragments (27,330 MP/m) and silver color MPs (25,310 MP/kg) were the most common in solid samples (river sediments, mangrove mud, and sand).

The challenges, opportunities and future of comparative physiology in the Global South: perspectives of early-career researchers.

Researchers in the Global South (GS, developing countries) make valuable contributions to the field of comparative physiology, but face economic and scientific disparities and several unique challenges compared with colleagues in the Global North (developed countries). This Perspective highlights some of the challenges, knowledge gaps and disparities in opportunity faced by GS researchers, especially those at early-career stages. We propose collaborative solutions to help address these issues, and advocate for promoting investment and cultural and societal change for a more inclusive research community.