Can short exposure to polyethylene microplastics change tadpoles' behavior? A study conducted with neotropical tadpole species belonging to order anura (Physalaemus cuvieri).

The scientific knowledge about toxicological impacts of polyethylene microplastics (PE MPs) on different organisms has significantly improved in recent years. However, the effects of these pollutants on animal species such as amphibians remain poorly known. Thus, the aim of the current study is to investigate whether the short exposure (7 days) of Physalaemus cuvieri tadpoles to PE MPs (60 mg/L) can change their behavior. Collected data have shown that PE MP accumulation in tadpoles was associated with different behavioral changes observed in them; this outcome has confirmed the behavioral toxicity of these micropollutants in the investigated species. Tadpoles subjected to PE MPs presented locomotion issues, anxiogenic effect symptoms, as well as anti-predatory defensive response deficit when they were exposed to predators (Cyprinus carpio). Data analysis enabled inferring to what extent these pollutants can affect individuals, and their natural predators living in contaminated areas. Based on the biological viewpoint, these changes can affect their defensive response to predators, as well as their social behavior. To the best of our knowledge, the present study was pioneer in reporting PE MPs-induced behavioral toxicity in representatives of amphibian groups.

A high throughput approach to rotating-disk sorptive extraction (RDSE) using laminar cork for the simultaneous determination of multiclass organic micro-pollutants in aqueous sample by GC-MS.

In this study, a high throughput approach to rotating-disk sorptive extraction (RDSE) using laminar cork as extraction phase is demonstrated for the first time in the determination of 20 multiclass organic micro-pollutants including pesticides, PAHs and UV filters compounds from aqueous samples with gas chromatography mass spectrometry (GC-MS). The influencing parameters (desorption solvent, volume and time, extraction time and sample pH and ionic strength) were carefully optimized using multivariate designs. The optimal conditions were 10 min for extraction using 35 mL of water samples and a liquid desorption using 1 mL of MeOH:AcOEt (50:50% v/v) for 20 min. A low-cost apparatus that allows six extractions simultaneously, providing a high throughput of 5 min per sample turnaround times, considering the sample preparation step was used for the first time in this modified RDSE methodology. Satisfactory analytical performance was achieved with limits of detection (LOD) between 0.08 and 1.5 µg L-1 and limits of quantification (LOQ) between 0.3 and 4.8 µg L-1. The relative recoveries for the analytes were determined using river and lake water samples spiked at different concentrations and ranging from 80% to 119% for all analytes, with relative standard deviations (RSD) lower than 20%. The extraction efficiency obtained for the proposed configuration with laminar cork was significantly superior to powdered cork, demonstrating an interesting new configuration for new applications.

Removal of pharmaceuticals from municipal wastewater by aerated submerged attached growth reactors.

The performance of four aerated submerged attached growth bioreactors was studied for the removal of three pharmaceutical micro-pollutants (fluoxetine, mefenamic acid and metoprolol) from municipal wastewater. Two packing materials (polyethylene tapes and polyurethane cubes) were compared and the effects of different organic loads (3.0, 6.0, 9.0 and 12 gCOD m-2 d-1) and of the effluent recirculation were investigated. The obtained solid retention times were in the range of 4-37 d. The reactors packed with polyurethane cubes allowed 11-26% higher biomass accumulation than the ones with polyethylene tapes and higher solid retention times. The low organic loads, high solid retention times and the implementation of effluent recirculation enhanced the removal of the three pharmaceutical compounds. The highest removals were achieved at organic load of 3 gCOD m-2 d-1 and 50% of effluent recirculation, with hydraulic residence times of 3.1-4.3 h and the solid retention times of 19-32 d. At this condition, the removals of the fluoxetine, mefenamic acid and metoprolol were up to 95, 82 and 73% respectively. The reactors with polyurethane cubes showed higher removals compared with the ones packed with polyethylene tapes.