Insight into the Interaction Between Microplastics and Microorganisms Based on a Bibliometric and Visualized Analysis

The ecological security risks of phthalates: A focus on antibiotic resistance gene dissemination in aquatic environments

Antibiotic resistance genes (ARGs) have become a major focus in environmental safety and human health, with concerns about non-antibiotic substances like microplastics facilitating their horizontal gene transfer. Phthalate esters (PAEs), as ubiquitous plastic additives, are prevalent in aquatic environments, yet there remains a dearth of studies examining their impacts on ARG dissemination. This study focuses on dibutyl phthalate (DBP), a prototypical PAE, to assess its potential influence on the conjugative transfer of ARGs along with the related molecular mechanisms. The results revealed that DBP exposure at environmentally relevant concentrations significantly promoted the conjugative transfer of RP4 plasmid-mediated ARGs by up to 2.7-fold compared to that of the control group, whereas it severely suppressed the conjugation at a high concentration (100 μg/L). The promotion of conjugation transfer by low-concentration DBP (0.01-10 μg/L) was mainly attributed to the stimulation of ROS, enhanced membrane permeability, increased energy synthesis, increased polymeric substances secretion, and upregulation of conjugation-related genes. Conversely, high DBP exposure induced oxidative damage and reduced ATP synthesis, resulting in the suppression of ARG conjugation. Notably, donor and recipient bacteria responded differently to DBP-induced oxidative stress. This study explores the environmental behavior of DBP in the water environment from the perspective of ARG propagation and provides essential data and theoretical insights to raise public awareness about the ecological security risks of PAEs.

Microplastics - A Growing Concern as Carcinogens in Cancer Etiology: Emphasis on Biochemical and Molecular Mechanisms

In today's world, the widespread presence of microplastics is undeniable, with concentrations found in various environments, including up to 1000 particles per liter in seawater and up to 10 particles per cubic meter in the atmosphere. Originating from diverse sources, both intentional and unintentional, these minuscule fragments, measuring less than 5 mm, pose significant threats to environmental and human health. Recent research has uncovered a concerning link between microplastics and cancer, prompting urgent investigation. Studies demonstrate microplastics can infiltrate cells, disrupt biological processes, and potentially foster carcinogenic environments. From inducing DNA damage and oxidative stress to triggering inflammatory responses and dysregulating cellular pathways, microplastics exhibit a multifaceted capability in contributing to cancer development. Furthermore, microplastics act as carriers for a range of contaminants, compounding their impact on human health. Their accumulation within tissues and organs raises concerns for short and long-term health consequences, including chronic diseases, reproductive issues, and developmental abnormalities. This review explores the biochemical and molecular mechanisms underlying the interaction between microplastics and cellular systems, providing insights into routes of exposure and health effects, with a focus on lung, skin, and digestive system cancers. As we confront this pressing environmental and public health challenge, a deeper understanding of the microplastic-cancer relationship is crucial to safeguarding the well-being of present and future generations.

Decadal changes in microplastic accumulation in freshwater sediments: Evaluating influencing factors

Microplastics are small plastic particles with sizes ranging between 1 μm and 5 mm. Microplastics can originate from macro plastics and degrade to a smaller size or be produced directly by manufacturers. Few studies have examined microplastic contamination in freshwater sediment cores to estimate changes in microplastic contamination over time. We present the results of a study that examined sediment cores from four watersheds, Kiskiminetas River, Blacklick Creek, Raystown Lake, and Darby Creek, in Pennsylvania, USA to reveal the history of microplastic accumulation and factors that contribute to microplastic distribution. The abundance and morphology of microplastics varied over time and between these four locations. The highest microplastic abundance was found in Raystown Lake, ranging from 704 to 5397 particles kg-1 with fiber as the dominant microplastic type, while Darby Creek (0-3000 particles kg-1), Kiskiminetas River (0-448 particles kg-1), and Blacklick Creek (0-156 particles kg-1) had lower microplastic concentration. Moreover, Darby Creek had the most diverse microplastic morphology and a trend of decreasing concentration with depth. Although the Darby Creek watershed has the most developed area and highest population density, it did not have the highest microplastic concentration. Averaged over the four cores, microplastic abundance increased as global plastics production increased from the 1950s-2010s. Our findings provide insights into the fate and transport of microplastic contamination in freshwater environments, which is vital to establishing sustainable mitigation strategies.

Advances and future directions of environmental risk research: A bibliometric review

Environmental risk is one of the world's most significant threats, projected to be the leading risk over the next decade. It has garnered global attention due to increasingly severe environmental issues, such as climate change and ecosystem degradation. Research and technology on environmental risks are gradually developing, and the scope of environmental risk study is also expanding. Here, we developed a tailored bibliometric method, incorporating co-occurrence network analysis, cluster analysis, trend factor analysis, patent primary path analysis, and patent map methods, to explore the status, hotspots, and trends of environment risk research over the past three decades. According to the bibliometric results, the publications and patents related to environmental risk have reached explosive growth since 2018. The primary topics in environmental risk research mainly involve (a) ecotoxicology risk of emerging contaminants (ECs), (b) environmental risk induced by climate change, (c) air pollution and health risk assessment, (d) soil contamination and risk prevention, and (e) environmental risk of heavy metal. Recently, the hotspots of this field have shifted into artificial intelligence (AI) based techniques and environmental risk of climate change and ECs. More research is needed to assess ecological and health risk of ECs, to formulize mitigation and adaptation strategies for climate change risks, and to develop AI-based environmental risk assessment and control technology. This study provides the first comprehensive overview of recent advances in environmental risk research, suggesting future research directions based on current understanding and limitations.

Graphene Oxide (GO) for the Treatment of Bone Cancer: A Systematic Review and Bibliometric Analysis

Cancer is a severe disease that, in 2022, caused more than 9.89 million deaths worldwide. One worrisome type of cancer is bone cancer, such as osteosarcoma and Ewing tumors, which occur more frequently in infants. This study shows an active interest in the use of graphene oxide and its derivatives in therapy against bone cancer. We present a systematic review analyzing the current state of the art related to the use of GO in treating osteosarcoma, through evaluating the existing literature. In this sense, studies focused on GO-based nanomaterials for potential applications against osteosarcoma were reviewed, which has revealed that there is an excellent trend toward the use of GO-based nanomaterials, based on their thermal and anti-cancer activities, for the treatment of osteosarcoma through various therapeutic approaches. However, more research is needed to develop highly efficient localized therapies. It is suggested, therefore, that photodynamic therapy, photothermal therapy, and the use of nanocarriers should be considered as non-invasive, more specific, and efficient alternatives in the treatment of osteosarcoma. These options present promising approaches to enhance the effectiveness of therapy while also seeking to reduce side effects and minimize the damage to surrounding healthy tissues. The bibliometric analysis of photothermal and photochemical treatments of graphene oxide and reduced graphene oxide from January 2004 to December 2022 extracted 948 documents with its search strategy, mainly related to research papers, review papers, and conference papers, demonstrating a high-impact field supported by the need for more selective and efficient bone cancer therapies. The central countries leading the research are the United States, Iran, Italy, Germany, China, South Korea, and Australia, with strong collaborations worldwide. At the same time, the most-cited papers were published in journals with impact factors of more than 6.0 (2021), with more than 290 citations. Additionally, the journals that published the most on the topic are high impact factor journals, according to the analysis performed, demonstrating the high impact of the research field.

Global research hotspots and trends on microplastics: a bibliometric analysis

In recent years, microplastics have become an integral part of the terrestrial and aquatic environments, which is one of the major concerns of communities around the world. Therefore, it is necessary to know the current status of studies and feasible potentials in the future. This study, conducted an in-depth bibliometric analysis of publications from 1990 to 2022 to present the influential countries, authors, institutes, papers, and journals on microplastics. Findings reveal that there has been a steady increase in microplastic publications and citations in recent years. And, the number of publications and citations has increased 19 and 35 times since 2015. Besides, we performed a comprehensive keyword analysis to show the significant keywords and clusters in this field. In particular, this study used the TF-IDF method as a text-mining analysis to extract the new keywords used in recent years (i.e., 2020-2022). New keywords can draw the attention of scholars to important issues and provide a basis for future research directions.

Different Distribution of Core Microbiota in Upper Soil Layer in Two Places of North China Plain

Backgrounds:

Soils harbor diverse bacteria, and these bacteria play important roles in soil nutrition cycling and carbon storage. Numerous investigations of soil microbiota had been performed, and the core microbiota in different soil or vegetation soil types had been described. The upper layer of soil, as a source of organic matter, is important and affected by the habitats and dominant bacteria. However, the complexity of soil environments and relatively limited information of many geographic areas had attracted great attention on comprehensive exploration of soil microbes in enormous types of soil.

Methods:

To reveal the core upper layer soil microbiota, soil samples from metropolis and countryside regions in the North China Plain were investigated using high-throughput sequencing strategy.

Results:

The results showed that the most dominant bacteria are Proteobacteria (38.34%), Actinobacteria (20.56%), and Acidobacteria (15.18%). At the genus-level, the most abundant known genera are Gaiella (3.66%), Sphingomonas (3.6%), Acidobacteria Gp6 (3.52%), and Nocardioides (2.1%). Moreover, several dominant operational taxanomy units OTUs, such as OTU_3 and OTU_17, were identified to be associated with the soil environment. Microbial distributions of the metropolis samples were different from the countryside samples, which may reflect the environments in the countryside were more diverse than in the metropolis. Microbial diversity and evenness were higher in the metropolis than in the countryside, which might due to the fact that human activity increased the microbial diversity in the metropolis.

Conclusion:

The upper layer soil core microbiota of the North China Plain were complex, and microbial distributions in these two places might be mainly affected by the human activity and environmental factors, not by the distance. Our data highlights the upper layer soil core microbiota in North China Plain, and provides insights for future soil microbial distribution studies in central China.

Single and combined effects of antibiotics and nanoplastics from surgical masks and plastic bottles on pathogens

Over the last decade, pollution of plastics and antibiotics has increased in its threat to the environment and human health. However, very limited information is available concerning impact of co-presence of plastics and antibiotics on environment and human health. Moreover, the potential ingestion and inhalation of nano(micro)plastics due to the disposable materials has dramatically increased. With the outbreak and spread of the COVID-19 in the world, disposable surgical masks and plastic bottles have been widely used by the public, and their rapid use and improper dispensing can cause to increase plastic pollution risk on human. However, impacts of co-presence of nano(micro)plastics and antibiotics on pathogens have yet been demonstrated. Therefore, this study aims to investigate the impact the individual and combined influences of nano-sized plastics (surgical mask and plastic bottles) and antibiotics (amoxicillin and spiramycin) towards the main susceptible bacterium (Staphylococcus epidermidis, Staphylococcus aureus, Bacillus subtilis, Escherichia coli, and Pseudomonas aeruginosa) by microbial activity, biofilm formation and their biochemical characteristics. The results showed that antimicrobial efficiencies of the tested antibiotics were reduced (approximately 10-98%) with the plastics. Moreover, the biochemical pathways of the microbial activity changed by the plastics entrance. Polymer structure and sorption play the role on the reduction in the inhibition of pathogens. In the meantime, the biofilm formation changed and characteristic of the extracellular polymeric substance with the co-presence of plastics and antibiotics mostly depended on the polymer structure, exposure time and sorption.

A Bibliometric Analysis of Research Trends in Biodegradation of Plastics

The rapid growth in the production and application of plastic globally has resulted in plastic pollution with a negative impact on the environment, especially the marine ecosystem. One main disadvantage in the majority of polymers is disposal after a useful life span. Non-degradable polymers create severe difficulty in plastic waste management that might end up in landfills or wash into the ocean. The biodegradation of plastic waste is one solution to this critical problem of pollution. Hence, there is a need to consider the advancement of research in this subject area, in pursuit of a way out of plastic pollution. Thus, this study was designed to map the biodegradation of plastic-related research from 2000 to 2021. Statistical information on the topic was recovered from the Web of Science Core Collection and analysed using the bibliometrix package in RStudio statistical software, while data visualisation was conducted via VOSviewer. Our evaluation indicated that the amount of research on the biodegradation of plastic increased over the last decade, and the annual growth rate of publication trends was 11.84%. The study revealed that 1131 authors wrote the 290 analysed documents, with a collaboration index of 4.04. Cooper DG (n = 11) was the most relevant author, McGill University (n = 21) was the most active university, and the Journal of Polymers and the Environment (n = 19) the leading journal. The outcome of this study can guide prospective research and offer vital information for improving the management of plastic waste.

Advances in Studies on Microbiota Involved in Nitrogen Removal Processes and Their Applications in Wastewater Treatment

The discharge of excess nitrogenous pollutants in rivers or other water bodies often leads to serious ecological problems and results in the collapse of aquatic ecosystems. Nitrogenous pollutants are often derived from the inefficient treatment of industrial wastewater. The biological treatment of industrial wastewater for the removal of nitrogen pollution is a green and efficient strategy. In the initial stage of the nitrogen removal process, the nitrogenous pollutants are converted to ammonia. Traditionally, nitrification and denitrification processes have been used for nitrogen removal in industrial wastewater; while currently, more efficient processes, such as simultaneous nitrification-denitrification, partial nitrification-anammox, and partial denitrification-anammox processes, are used. The microorganisms participating in nitrogen pollutant removal processes are diverse, but information about them is limited. In this review, we summarize the microbiota participating in nitrogen removal processes, their pathways, and associated functional genes. We have also discussed the design of efficient industrial wastewater treatment processes for the removal of nitrogenous pollutants and the application of microbiome engineering technology and synthetic biology strategies in the modulation of the nitrogen removal process. This review thus provides insights that would help in improving the efficiency of nitrogen pollutant removal from industrial wastewater.