Resumo em Inglês:

Abstract The present study aimed to establish and validate a standardized protocol for the collection, treatment, and characterization of microplastic samples found in beach sands. The methodology was implemented at Praia Vermelha/RJ, demonstrating its effectiveness in identifying and assessing microplastics originating from improper plastic waste disposal in coastal environments. The flotation method showed high efficiency in extracting microplastics, and the subsequent sample treatment, including thorough cleaning and drying processes, ensured reliable results. Through systematic sampling across multiple sections of the beach, a total of 32 microplastics were identified, with polystyrene being the predominant polymer. Optical microscopy effectively confirmed the presence of microplastics, revealing that the most common form was foam, with average sample diameters ranging from 2.1 mm to 4 mm. Fourier Infrared spectroscopy further confirmed the polymer composition, highlighting the dominance of polystyrene among the samples. This study underscores the importance of standardizing collection and analysis protocols for microplastics to enable consistent comparisons across regions and scales. Furthermore, the findings emphasize the urgent need for preventive measures and management strategies to reduce the influx of microplastics into coastal and marine ecosystems. Raising public awareness and promoting sustainable practices are critical steps toward mitigating the environmental impact of plastic pollution.

Resumo em Inglês:

Abstract Marine pollution by plastics is a major environmental issue that is expected to increase worldwide. Thousands of chemical substances can be used as plastic additives in industrial processes for various purposes, turning plastics into chemical carriers of such substances. If plastics are discarded in the marine environment, these chemicals can be released into the environment and cause toxicity to marine species. In this review, we analyze the toxicity of chemical groups that are commonly used as plastic additives (bisphenol-A, alkylphenols, tetrabromobisphenol, phthalates, polybrominated diphenyl ethers, and per- and polyfluoroalkyl substances) in marine organisms. Little information has been obtained because only a small number of studies have been conducted on marine species. However, the existing information indicates high toxicity of most chemical groups, with the Lowest Observed Effect Concentrations (LOECs) on the order of micrograms per liter (e.g. bisphenol-A, para-nonylphenol, nonylphenol, octylphenol, Di(2-ethylhexyl) phthalate, BDE-47). Per- and polyfluoroalkyl substances (PFAS) were toxic at milligrams per liter. These results provide evidence that chemicals added to plastics may represent a threat to marine organisms, and further research on the toxicity of these substances is urgently needed.

Resumo em Inglês:

Abstract Microplastics (MPs) production and degradation are becoming a global concern. They accumulate across diverse environments, animals, and human tissues, closely linking to emerging environmental health impacts. In the Brazilian population, no evidence yet of accumulation in pregnant women’s placenta or umbilical cord. In this pilot cross-sectional, observational study, we analyzed the presence, size, and composition of MPs isolated from placentas (n=10) and umbilical cords (n=10) from Maceio pregnant women. Under a plastic-controlled protocol, samples were digested with 10% KOH solution, glass-filtered, and retained particles were then analyzed by Raman spectroscopy. A total of 229 MPs were identified across all samples, including 110 in placental tissues and 119 in umbilical cord tissues. The predominant polymers were polyethylene (PE), polyamide (PA), polyethylene vinyl acetate (PEVA), polyurethane (PU), and polypropylene (PP). Our results demonstrated for the first time the accumulation of MPs in the placentas and umbilical cords of Brazilian pregnant women. This accumulation suggests that pregnant women in Maceio, Brazil, are likely experiencing microplastic (MP) exposure similar to global trends, emphasizing the importance of studying the mechanisms that facilitate the transport of MPs and related chemicals across the placental barrier.

Resumo em Inglês:

Abstract Although the contamination of microplastics is a very recent topic, knowledge increased rapidly, especially in the last decade. Despite this, freshwater ecosystems have received less attention than marine ones, particularly in the tropics. Considering the particularities of Tropical freshwater ecosystems that can be important in the microplastics dynamic, such as the high rate of untreated water, the flooding dynamics and high number of reservoirs, our review aims to present the state of the research of microplastic contamination in Tropical freshwater ecosystems, emphasizing the knowledge advances and existing gaps. We compared studies in different countries, ecosystems and type of samples, and identified gaps and needs for futures research. Although research and the complexity of studies have increased over the years, Tropical freshwater ecosystems are still understudied. We emphasized the need for more studies in African countries and Tropical Australia, as well as in reservoirs across all Tropical regions. It is also crucial to evaluate contamination related to flooding dynamics and in aquatic invertebrates. Advancements in research on this topic are essential to provide a clear picture of the real problem in the tropics, leading to the possibility of better mitigation and conservation actions in the future.

Resumo em Inglês:

Abstract The increasing presence of nanoplastics in the environment raises concerns about their toxic effects on human health and ecosystems, including bioaccumulation, pollution, and unknown impacts on the food chain and marine organisms. With the rise of polymer pollution, it is urgent to understand the characteristics of this new pollutant. This study uses bibliometric analysis to elucidate the state-of-the-art on nanoplastics and their adsorption capacity, highlighting concerns, advances, and research gaps. Tools like Vosviewer® and Python were used to identify trends in publications, noting a significant increase since 2018, with China leading scientific production. The review details the physicochemical characteristics of nanoplastics, characterization methods, and adsorption mechanisms, emphasizing interactions with environmental contaminants and health effects. Public policies and advanced detection techniques are necessary. Significant gaps require investigation to mitigate the impacts of nanoplastics on the environment and human health.

Resumo em Inglês:

Abstract We analyzed methodological similarities and discrepancies regarding microplastics (MPs) pollution studies in South American continental aquatic environments (lotic and lentic systems). A systematic search up to October 2024 on ScienceDirect, Scopus, Web of Science, and Scielo returned 57 papers, the first being published in 2017. Papers from Brazil were the most frequent, particularly in the Amazon region. Methodological discrepancies, especially in sampling, detection limits and sample preparation, limit data comparability and impact progress toward understanding MPs’ environmental impact. Harmonizing methodologies and broadening geographic coverage are crucial. Recommendations include regional collaboration, integrated studies, and enhanced analytical approaches to improve environmental diagnostics and support policy development for plastic pollution management.

Resumo em Inglês:

Abstract This study describes the spatial and temporal distribution of density and biomass, feeding ecology and contamination by microplastics (MPs) in <italic>A. clupeoides</italic> and <italic>C. edentulus</italic> in the Goiana Estuary. <italic>A. clupeoides</italic> were found in all portions of the estuary, mainly in the late rainy and late dry seasons. <italic>C. edentulus</italic> was found in the upper and lower portions of the estuary mainly in the late dry season. <italic>A. clupeoides</italic>’ adult specimens fed mainly on copepods in the lower estuary during the beginning of the rainy season when they were contaminated by black MPs. <italic>A. flexuosa</italic> larvae were consumed by subadults in the lower portion during the final rainy season and by juveniles in the lower portion during the end of the dry season when they were contaminated by the same type and color of MPs. The species <italic>C. edentulus</italic> both adults and subadults feed on <italic>Coscinodiscus sp</italic>. and <italic>Actinopthycus sp</italic>. in the lower portion during the final rainy season. At this time, adults were contaminated by blue MPs. MPs’ samples were analyzed by FTIR, were composed of polyethylene<italic>.</italic>

Resumo em Inglês:

Abstract Micro- and nanoplastics (MNPs) are emerging contaminants increasingly recognized for their environmental and health implications. While surface water systems have been extensively studied, the presence, behavior, and impacts of MNPs in groundwater remain underexplored, despite its critical role as water source worldwide. The findings in this review highlight that agricultural activities, particularly plastic mulches, pesticides containers, fertilizer bags, greenhouses, are major sources of MNP. Nanoplastics, predominant in groundwater due to their enhanced mobility in the vadose zone, exhibit a higher sorption capacity, facilitating the transport and accumulation of toxic substances such as hydrophobic organic pollutants and trace metals to/in groundwater. The review also discusses the hydrogeological and environmental factors influencing micro(nano)plastics distribution. In complement, synergistic and antagonistic effects arising from MNP interactions with other contaminants were reviewed, emphasizing the interactions with contaminants derived from agricultural practices (nitrate, herbicides, pesticides, and salts). Despite the generally low concentrations of MNPs in groundwater, their seasonal variability, combined with the aging of particles, underscores the need for long-term monitoring and risk assessments specific to groundwater systems. These findings reinforce the importance of research that addresses the unique challenges posed by micro- and nanoplastics in groundwater systems, ensuring their environmental protection.

Resumo em Inglês:

Abstract Microplastic (MP) contamination is a global problem that affects several ecosystems. This contamination is present in streams in the Amazon region, which is subject to great risks through anthropogenic actions. The present study verified the possible relationship between the physical integrity of the habitat and the levels of MP contamination in Amazonian streams, evaluating which environmental component, among water, sediment and biodiversity (fish) was most contaminated by MPs and which type of polymer was most present. No relationship was found between the integrity of the environment and the concentration of MPs in streams. The concentration of MPs in the sediments was higher than that found in the water, and only eight fish specimens were contaminated. Despite the low concentration rates of MPs recorded, our results suggest that streams can function as a deposit of MPs. It is possible that the lower level of contamination is associated with the low presence of point sources of MPs, as well as some physical factors that can transport MPs to other systems. The low concentration of MPs in streams may explain lower ingestion rates by fish, since low concentrations of particles in the environment reduce the chances of ingestion of these particles by organisms.

Resumo em Inglês:

Abstract Microplastic contamination has become an urgent concern for global ecosystems, especially for wildlife health in areas under intense anthropogenic pressures. This study analyzes the presence of microplastics in fruit bats (Phyllostomidae: Stenodermatinae and Carolliinae) in two Brazilian biomes: Cerrado and Amazon. Surprisingly, bats from the Amazon presented higher levels of contamination than those from the Cerrado, challenging the idea that more open and historically modified landscapes, such as the Cerrado, would have higher contamination. Land use and land cover classifications did not influence contamination levels, indicating that habitat-specific factors play a more relevant role. Contamination varied by organ, with the stomach presenting the highest concentrations in both biomes. Interestingly, bats from the subfamily Carolliinae, with more varied diets, presented higher contamination, probably due to dietary exposure and inhalation in anthropogenically altered areas. This study is the first to record microplastics in Cerrado bats and in detoxifying organs such as the liver. Our findings highlight the vulnerability of bats to microplastic pollution and the need for further research into its impacts, as well as suggesting conservation measures in regions of rapidly changing biodiversity.

Resumo em Inglês:

Abstract While numerous studies in Brazil have investigated plastic interactions with aquatic organisms across various environments, there is no comprehensive overview or identification of research gaps. Using a dataset compiled from scientific studies conducted within the country, we systematically reviewed the current research on plastics in Brazilian aquatic environments. The search yielded 178 publications on plastic interactions with aquatic life in Brazil, published in the past 21 years on plastic pollution in aquatic habitats. Most studies were field-based, assessing plastic ingestion by various organisms. Since 2015, experimental approaches have been developed in the country, with most of studies focusing on particle ingestion by organisms. Fish were the dominant taxonomic group in both field and experimental studies. Microplastics and blue-colored particles were the most studied in terms of size and color. A lack of standardized microplastic sampling and processing methods hinders meta-analyses and regional or national integration levels.

Resumo em Inglês:

Abstract Microplastic has stood out as one of the main contaminants derived from plastic wastes due to its slow decomposition rate and dangers to the aquatic environment, the ecosystem, and even human health. However, microplastic fragment detection, identification, removal, and quantification remain a challenge. One of the main methods of removing these fragments is the filtration process using filter membranes such as paper, glass fibers, wool, etc. Among several techniques for localizing and identifying these fragments, optical microscopy is an easily accessible alternative, however, the spatialization to locate these fragments has become a challenge for equipment operators. This work proposes a simple spatialization system using coordinates that reduce operation time to make the localization of microplastic fragments onto collector filters easy. In addition to the use of an optical microscope, a micro-Raman was used to demonstrate the efficiency of this spatialization system even in another type of microscope, reducing the operating time from 2 hours and 45 minutes to approximately 2 minutes and 20 seconds, making the search for the fragment more effective and consequently, a faster analysis process.

Resumo em Inglês:

Abstract Plastic pollution has become commonplace and knowledge about microplastics is limited in relation to their real threat to the aquatic biota present in the Amazon basin. Through fish species collected in Lake Janauacá and the Anavilhanas Archipelago, in the state of Amazonas, Brazil, we investigated the ingestion of microplastics by Amazonian fish species with different eating habits. The fish were dissected, and the gastrointestinal tract underwent alkaline digestion for the separation of the microplastic particles. Using a stereomicroscope, the items characterized as microplastics were subjected to Fourier-transform infrared spectroscopy. Almost >60% of the analyzed fish species contained microplastics in their gastrointestinal tracts. Most of the microplastics were found in the intestine (91.5%) and the rest (8.5%) in the stomach. There were no significant differences in the feeding habits of the studied species, or between the locations. The characterization of microplastics highlights the possible sources of the microplastics such as discarded fishing artifacts, the lack of basic sanitation evident in the region and the lack of environmental education for tourists. This study provides data that can assist in the development and formation of practices that combat plastic pollution and raises awareness in regard to the correct disposal of plastics.

Resumo em Inglês:

Abstract Fish in the Amazon basin have adapted to bouts of low water O2 and high CO2, with many species evolving air-breathing or aquatic surface respiration mechanisms to supplement respiratory gas exchange. While concurrently coping with greater instances of hypoxic and hypercarbic stress, fish in the Amazon are also facing microplastic pollution. Assessments of the Amazon basin reveal some of the highest microplastic concentrations globally. In this article, we highlight instances in which the evolution of air-breathing and aquatic surface respiration may make fish of the Amazon particularly susceptible to the effects of microplastic pollution. We consider these effects as they relate to gill morphology, specialized air-breathing organs, ion transport processes, aquatic surface respiration, and oxidative stress. Finally, we relate our perspectives with the recently published Executive Summary of the Status of Water Quality in the Amazon Basin to highlight the importance of considering microplastics alongside other pollutants threatening the ecological, economical, and cultural values of the Amazon.

Resumo em Inglês:

Abstract Microplastics are a serious environmental threat, impacting biodiversity, ecosystem integrity, and human health. Controlling and mitigating these effects requires a detailed understanding of the physicochemical characteristics of these contaminants. This study aims to enhance the analysis of microplastics in aquatic environments by focusing on the optimization and integration of advanced characterization techniques, such as Fourier Transform Infrared Spectroscopy and Raman Spectroscopy. The goal is to improve accuracy in identifying the polymers that makeup microplastics, which is crucial for developing effective strategies for mitigating and controlling aquatic contamination. To this end, the application of Surface-Enhanced Raman Spectroscopy is suggested in this review article, as it significantly improves signal-to-noise ratio, enabling more detailed detection of plastic residues and adsorbed microorganisms. These integrated analyses facilitate the acquisition of more robust and detailed data, essential for formulating effective solutions to the microplastics problem. Additionally, FTIR and Raman spectra were generated for polymers commonly found as microplastics, such as PP, LDPE, PS, and PVC, due to their widespread use in various materials. These standards will provide crucial data for identifying unknown microplastics, significantly contributing to the accuracy and reliability of the analyses.

Resumo em Inglês:

Abstract This study introduces a hybrid method to identify and analyze techniques for microplastic analysis. We improve the detection and understanding of both established and new techniques by integrating regex-based pattern detection with the Llama 3.2:3b language model. Techniques like Raman and FTIR spectroscopy are explored alongside advanced tools, such as X-ray Photoelectron Spectroscopy (XPS) and Surface-Enhanced Raman Spectroscopy (SERS). This combination enhances the accuracy and speed of identifying complex terminology related to microplastics research. Data analysis and visualization were conducted using VOSDataAnalyzer and VOSviewer, allowing us to map connections and trends within a network of related terms. This analysis identified the 15 most commonly used and emerging techniques, showing a shift toward more sensitive and innovative methods in microplastic studies. This novel Regex-Llama approach, introduced here for the first time, provides a scalable methodology applicable to various searches, including the analysis of pollutants in environmental science, the evaluation of material degradation in materials engineering, and the assessment of the toxicological effects of micro-contaminants on public health. This strategy facilitates environmental evaluations and aids in formulating pollution reduction measures, addressing many difficulties across several interesting fields.

Resumo em Inglês:

Abstract The occurrence of microplastics (MPs) in aquatic environments is constantly expanding. This paper aims to provide a comprehensive analysis of the concentrations, typologies, and fate of MPs in water and wastewater. Their occurrence and toxicity were examined, detailing an analytical approach for detection, quantification, and remediation. A diversity of studies that include countries of all continents was collected and compared to identify patterns of composition and size, in addition to analyzing the distribution of MPs. The study showed that polyethylene and polypropylene were the most common polymers in surface waters, being reported on all continents. PET and PE stood out as the polymers with the highest environmental risk. However, few studies were observed in developing countries. South America, both for water and wastewater, was the continent with the fewest studies reported in literature. MP presence was confirmed in countries such as Brazil and Bolivia, but few studies reported these identifications and quantifications. These gaps can impede the formulation and implementation of effective policies. Thus, developing robust legislation to identify, quantify, and regulate MPs is essential to protect the environment and public health.

Resumo em Inglês:

Abstract The persistent accumulation of microplastics from synthetic polymers threatens ecosystems and biodiversity. The use of biodegradable and compostable materials as alternatives to conventional plastics in food packaging has shown promise, particularly with the development of nanocomposites that can be tailored to meet market demands. In this study, ZnO and TiO₂ nanoparticles were combined and incorporated into a biodegradable poly(butylene adipate-co-terephthalate) (PBAT) matrix at varying concentrations, forming a novel ternary PBAT/ZnO/TiO₂ system. The films produced via melt processing were characterized using conventional and non-conventional techniques to evaluate their thermal, morphological, chemical, wettability, and biosafety properties. The results indicated that the combined addition of ZnO and TiO₂ slightly reduced the thermal stability and crystallinity of PBAT, while increasing surface hydrophilicity. These features may contribute to accelerated degradation and reduced environmental persistence. Furthermore, improvements in the elastic modulus and enhanced biosafety were observed across all tested concentrations. These findings suggest that the prepared nanocomposites, particularly at 0.75 and 1 wt%, not only possess properties suitable for food packaging applications but also demonstrate potential to mitigate environmental persistence through accelerated degradation. Therefore, this study supports the development of environmentally friendly materials for food packaging, addressing the urgent need to reduce microplastic pollution.

Resumo em Inglês:

Abstract The degradation of plastic materials has led to the emergence of new forms of reduced size (≤ 5 mm); know as microplastics (MPs). The presence of microplastics is a growing concern due to their persistence and, consequently, their ability to disseminate environmental pollutants. This review, in addition to providing an overview of the accumulation of plastic waste, which poses a risk to aquatic organisms and human health, seeks alternatives to mitigate this problem. To this end, we sought to address the main causes, sources, affected sites (soil, air, water), as well as the possible harmful effects caused by the presence of MPs on aquatic organisms and humans. The circular economy system has become an alternative for effectively reducing MPs in nature. In this context, we also presented an overview of trends in MP recycling, pollution control, and how proposed legislation on single-use plastic production is being discussed. Finally, an overview of scientific publications on the subject over the last ten years was presented.

Resumo em Inglês:

Abstract High-impact polystyrene (HIPS) nanocomposites containing organoclay were investigated under UV-accelerated aging using solid-state NMR to elucidate the evolution of molecular mobility and morphology. 13C CPMAS with variable contact time (VCT) and proton spin–lattice relaxation in the rotating frame (T₁ρH) sensitively captured the competition between chain scission and recombination across the nanocomposite films before and after exposure. The 1 wt% formulation predominantly displayed intercalated character with attenuated mobility changes upon aging, whereas 2–3 wt% systems showed heterogeneous and partially exfoliated morphologies with amplified mobility. While solid-state NMR does not directly detect microplastic particles, the relaxation signatures provide molecular-level evidence of fragmentation pathways with implications for potential microplastic formation.