The ubiquity of microplastics ecosystems has gained global attention. In this context, Latin America, which is responsible for 8% of the world’s consumption of plastic material and has a small recycling rate (4.5%), does not have enough data on microplastics contamination in its environmental matrices. This systematic review analyzed 196 studies from 16 territorials in Latin America and provided information about the current state of knowledge regarding the abundance, distribution, and associated impact of microplastics in different matrices. This review also describes the analytical procedures of sampling, extraction, identification, and characterization methodologies adopted by the literature review. The analysis shows that most of the studies that investigate microplastics abundance were carried out in the marine environment (59%), and there is an insufficient investigation on microplastics abundance in freshwater bodies (16%). Among all the studies, the highest microplastics concentration was observed in regions with high population density and/or in locations without proper sanitation and solid waste management. Additionally, the difference among microplastics abundance in the studies might be associated with the different analytical procedures employed to investigate microplastics. Lastly, knowledge gaps are identified, and recommendations are proposed to guide future studies on microplastics contamination.

Abstract Background The use of carbonaceous materials for environmental remediation is attractive due to low expense and high sorption capacity. However, their efficiency in contaminant removal is affected by substrate composition and sorption mechanism. Objective This study investigated atrazine sorption and desorption in three carbon-rich substrates. Data were evaluated considering isotherm models and sorbent chemical composition. Methods Sorption was performed by the batch equilibrium method with three substrates obtained from pig slurry composting with different proportions (w/w) of charcoal fines (CF): CF0, CF9 (9% CF), and CF18 (18% CF). The substrates were characterized by elemental analysis, 13C NMR CP/MAS spectroscopy. The Freundlich and Dubinin-Radushkevich (DRK) models better fitted the sorption data (0.96>R2>0.81), followed by Temkin (0.95>R2>0.76). Charcoal addition to composting substrates increased carbon content and the aromaticity in the order CF0<CF9< CF18. However, the sorption affinity decreased in the opposite order as indicated by the Kf values: 675, 335 and 290 L kg-1, respectively. Values of the E parameter (DRK) varied from 8.05 to 8.29 kJ mol-1, suggesting a predominant physical sorption mechanism, whereas the Bt coefficient (Temkin) indicated an endothermic process. Desorption was only observed at higher atrazine concentrations (>10 mg L-1), and the desorption Kf values were greater than the respective sorption values. Conclusions Atrazine sorption in the tested C-rich substrates is not governed by the carbon content or aromaticity. The low sorption reversibility implies a low atrazine mobility from the tested substrates and suggests their potential for herbicide removal in the environment.