Plastic and its consequences during the COVID-19 pandemic

Advancing poliovirus eradication: lessons learned from piloting direct molecular detection of polioviruses in high-risk and priority geographies

In the Global Polio Laboratory Network (GPLN), poliovirus (PV) screening results from acute flaccid paralysis (AFP) surveillance is based on virus isolation (VI) through cell culture, entailing long turnaround times and the amplification of live poliovirus. An alternative Direct Detection strategy (DD-ITD) for screening viral nucleic acid from stools, bypassing the need for virus culture, has been developed and extensively validated by GPLN partners. A multi-laboratory demonstration project was conceived to field-test the DD-ITD method by GPLN laboratories from the WHO African, Western Pacific, and Eastern Mediterranean regions, where wild serotype 1 or vaccine-derived polioviruses still circulate. Strategically selected laboratories were tasked to simultaneously process stool suspensions with the current gold-standard VI method and the new DD-ITD strategy. Results from 12 laboratories were compiled and analyzed to assess the quality of each RNA extraction and rRT-PCR run. Matched results for both methods of over 10,500 specimens showed an overall method agreement of 91%. All laboratories detected more PV presumptive positive samples with the DD-ITD strategy than with VI, but a large proportion of DD-ITD positive results (72%) were inconclusive or non-typeable, requiring confirmation through sequencing. A total of 298 (2.8%) samples were PV positive using both methods, 828 (7.9%) positive only for DD-ITD, and 62 (0.6%) positive only with VI. The DD-ITD overall performance, quality of results, and agreement between method results varied significantly across participating laboratories. DD-ITD implementation would entail building proficiency in advanced molecular laboratory techniques and data analysis, and increased demand for confirmatory sequencing.

IMPORTANCE

Surveillance of acute flaccid paralysis (AFP) and sensitive poliovirus detection are key components of the WHO Global Polio Eradication Strategy. This work summarizes the results of a multi-laboratory evaluation designed to field-test the performance and applicability of a molecular Direct Detection strategy (DD-ITD) that does not require amplification of live poliovirus. AFP samples were processed in parallel with both the DD-ITD and the current gold-standard PV detection methodology, based on virus isolation (VI) through cell culture. All participating laboratories detected more PV presumptive positive samples using the DD-ITD strategy than with virus isolation methodology, although a higher proportion of DD-ITD results required confirmatory sequencing. Significant variability among laboratories was observed in the quality of the results and overall DD-ITD performance. Implementing DD-ITD would entail building proficiency in advanced molecular laboratory techniques and strengthening data analysis skills.

Microplastics in aquaculture environments: Current occurrence, adverse effects, ecological risk, and nature-based mitigation solutions

Microplastics pose detrimental effects on the environment, aquatic products, and human health. This comprehensive analysis highlights the repercussions of microplastic contamination within aquaculture. Microplastics in aquaculture are primarily from land-based plastic waste, tourism-related disposal, shipping activities, fisheries/aquaculture, and atmospheric deposition. In aquaculture environments, microplastics have the potential to discharge harmful additives, attract pollutants, degrade the aquaculture setting, and induce toxicological effects. These particles pose ecological risks and can impact human health. Assessing the destiny of microplastics in aquaculture ecosystems is crucial to determining the role of aquaculture in contributing to microplastic contamination within the watershed. It particularly emphasizes the ecological consequences for aquaculture species and the subsequent health threats for humans. The review strongly supports strict regulations to control and limit microplastic presence within aquaculture ecosystems. Clear regulations are essential for reducing microplastics in aquaculture, thereby ensuring food safety. A novel nature-based solution is proposed using methods like microplastic biofilters, biodegradation, and wetlands. These innovations can be conducted in aquatic ecosystems to serve as microplastic biofilters, effectively eliminating waterborne microplastics. In the future, however, it is crucial to develop additional emergency treatment measures to avoid the potential negative impacts of microplastics on both aquaculture and human health.

Management of COVID-19 healthcare waste based on the circular economy hierarchy: A critical review

The overall objective of this work was to conduct a critical literature review on the application of the circular economy (CE) hierarchy for the management of COVID-19 healthcare waste (HCW). To describe the problem created by COVID-19 HCW, first, the subsystems of the overall management system, including generation, segregation, classification, storage, collection, transport, treatment and disposal, were reviewed and briefly described. Then, the CE hierarchy using the 10R typology was adapted to the management of COVID-19 HCW and included the strategies Refuse, Reduce, Resell/Reuse, Repair, Reprocess, Refurbish, Remanufacture, Repurpose, Recycle and Recover (energy). Disposal was added as a sink of residues from the CE strategies. Using the detailed 10R CE hierarchy for COVID-19 HCW management is the novelty of this review. It was concluded that R-strategy selection depends on its position in the CE hierarchy and medical item criticality and value. Indicative HCW components, which can be managed by each R-strategy, were compiled, but creating value by recovering infectious downgraded materials contaminated with body fluids and tissues is not currently possible. Therefore, after applying the circular solutions, the end of pipe treatment and disposal would be necessary to close material cycles at the end of their life cycles. Addressing the risks, knowledge gaps and policy recommendations of this article may help to combat COVID-19 and future pandemics without creating environmental crises.

Improving urban waste management: A comprehensive study on household waste generation and spatial patterns in the Grand Guayaquil Metropolitan Area

This study tackles the growing global concern about municipal waste management, particularly in cities like the Grand Guayaquil Metropolitan Area (GGA). Through realistic field studies on in situ household waste generation and geographic information system (GIS) tools, this work offers a framework to predict the quantities and types of recyclable household waste for any metropolitan area in Latin America. Over 4 weeks, students collected, sorted and weighed recyclable waste types, including plastic, paper, metal, glass and fabric, from 776 sampled household of the GGA. ArcGIS survey tool identified household locations and allowed to survey different socio-demographic features. With the help of ArcGIS interpolation method, the total household waste generation for GGA was predicted, and the classification of the different types of recyclable waste was also spatially distributed for the study area. The report identified notable trends in plastic waste, specifically polyethylene terephthalate waste's steady prevalence and 42% growth rate, emphasizing the importance of enhanced recycling techniques. Spatial density maps showed a heterogeneous waste distribution across the GGA, emphasizing locations with higher waste output. This study demonstrates that improving recyclable waste collection can be accomplished with a moderately cheap expenditure by collaborating with academia to overcome knowledge gaps. This strategy provides opportunities to mitigate the environmental impacts of poor waste management.

Eco-Friendly Straws: A Fusion of Soy Protein Isolate and Cassava Starch Coated with Beeswax and Shellac Wax

This research aimed to produce eco-friendly straws using soy protein isolate (SPI) and cassava starch (CS) at different ratios by the extrusion technique and by coating with beeswax and shellac wax. Three straw formulations (F) (F1: 24.39% SPI-24.39% CS; F2: 19.51% SPI-29.37% CS; and F3: 14.63% SPI-34.15% CS) were prepared, incorporating glycerol (14.6% w/w) and water (36.6% w/w). After extrusion and drying at 80 °C for 20 h, visual assessment favored F2 straws due to smoother surfaces, the absence of particles, and enhanced straightness. For the physical property test, the straws were softened in pH buffer solutions for 5 min. To simulate practical application, mechanical bending strength was studied under different relative humidity (RH) settings. Water absorption reduced the strength as RH increased. F2 straws outperformed other formulations in bending strength at 54% RH. For hydrophobic coatings, F2 was chosen. Beeswax- and shellac wax-coated straws displayed negligible water absorption and sustained their integrity for over 6 h compared to uncoated straws. This study shows that extrusion and natural coatings may make sustainable straws from SPI and CS. These efforts help meet the growing demand for eco-friendly plastic alternatives, opening up new options for single-use straws.

Morphology Distribution in Injection Molded Parts

A more sustainable use of plastic parts makes it necessary to replace current plastic parts with recyclable components, also allowing the modulation of the part properties through the process. Injection molding is one of the most widely used technologies for obtaining rigid plastic parts, so it is crucial to understand how to tailor properties by adopting the correct processing conditions. One way is to perform annealing steps directly inside the mold: in-mold annealing improves the structural integrity and durability of the material, reduces defects, increases the resistance of parts against certain chemicals, reduces wear and tear, increases ductility, and lowers brittleness. In this work, several in-mold annealing steps were conducted, changing the mold temperature and annealing duration selected on the basis of the half crystallization time of the adopted isotactic polypropylene. The typical molded part morphology, composed of oriented layers at the surface, transition zones, and spherulitic core, is strongly affected by in-mold annealing. In particular, the thickness of the oriented layer, which forms in the early phase of the process, decreases, and the spherulites increase in size. Concerning mechanical behavior, the orientation degree mostly determines the elastic modulus value close to the surface, whereas the conditions under which crystallization occurs determine the modulus in the core.

Sustainable management of drinking plastic straws is required to reduce plastic pollution: Are we using them more during COVID-19?

Nowadays, single-use plastic pollution attracts the attention of scholars, policymakers, and practitioners. In addition to personal protective equipment (PPEs) waste during the COVID-19 pandemic, other unpreceded plastic wastes such as packaging from online shopping and food delivery, viruses confirmatory testing, and drinking straws also contributed to pollution and worsened around the globe. This perspective aimed to provide insights into drinking plastic straws as an important source of plastic pollution. Literature searches confirmed that drinking plastic straws, unlike PPEs, have not been researched whether it is an important contributor to pollution or not during the COVID-19 pandemic. Thus, research on the pollution level of this plastic waste and its association with COVID-19 is required. Drinking straw producers and users require adequate strategies and management of this plastic pollution and more widespread rules and regulations to prevent environmental implications and health risks. This study can usefully give highlights for environmentalists, solid waste management experts, policymakers, and governments by describing the environmental impact and raising health risks of drinking plastic straw pollution.

Significantly High Melting Temperature of Homopolymer Crystals Obtained in a Poly(l-Lactic Acid)/Poly(d-Lactic Acid) (50/50) Blend

The isothermal crystallization of a poly(l-lactic acid) (PLLA)/poly(d-lactic acid) (PDLA) (50/50) blend, neat PLLA, and neat PDLA, was studied at different crystallization temperatures (110 °C, 150 °C, 170 and 180 °C) for different durations (1-300 min) by means of differential scanning calorimetry (DSC), polarized optical microscope (POM) observations, and time-resolved wide-angle X-ray diffraction (WAXD). The effects of both the isothermal crystallization temperature and the duration of the isothermal crystallization were investigated for the blend specimens fully crystallized at these crystallization temperatures. The formation of homopolymer crystallites (HC) was confirmed at the isothermal crystallization temperature of 170 °C, which was previously considered too high for its formation, after 70 min had elapsed from the temperature stabilization. Moreover, the melting temperature of the formed HC was found to be significantly high (Tm = 187.5 °C) compared to the one obtained during the nonisothermal DSC measurement of the same specimen of the PLLA/PDLA (50/50) blend, as well as the neat PLLA and PDLA specimens. To the best of our knowledge, this extremely high Tm (=187.5 °C) for HC has never been reported before.

Global plastic upcycling during and after the COVID-19 pandemic: The status and perspective

Plastic pollution has become one of the most pressing environmental issues worldwide since the vast majority of post-consumer plastics are hard to degrade in the environment. The coronavirus disease (COVID-19) pandemic had disrupted the previous effort of plastic pollution mitigation to a great extent due to the overflow of plastic-based medical waste. In the post-pandemic era, the remaining challenge is how to motivate global action towards a plastic circular economy. The need for one package of sustainable and systematic plastic upcycling approaches has never been greater to address such a challenge. In this review, we summarized the threat of plastic pollution during COVID-19 to public health and ecosystem. In order to solve the aforementioned challenges, we present a shifting concept, regeneration value from plastic waste, that provides four promising pathways to achieve a sustainable circular economy: 1) Increasing reusability and biodegradability of plastics; 2) Transforming plastic waste into high-value products by chemical approaches; 3) The closed-loop recycling can be promoted by biodegradation; 4) Involving renewable energy into plastic upcycling. Additionally, the joint efforts from different social perspectives are also encouraged to create the necessary economic and environmental impetus for a circular economy.

Characterization of plastic degrading bacteria isolated from sewage wastewater

Plastic is a fundamental polymer used in routine life and disposed of in sewage. It leads to microplastic pollution in aquatic organisms, introducing it into the food chain and affecting human health. In the present study, samples were collected from sewage wastewater to isolate the bacteria that could potentially reduce plastic. The six samples were incubated with plastic pieces in minimal salt media for 120 days. After 120 days, the weight loss experiment showed that samples SH5B and SH6B degraded 25% plastic. After chemical and molecular characterization, these strains were identified as Pseudomonas sp. SH5B and Pseudomonas aeruginosa SH6B. The Fourier-transform infrared spectroscopy (FTIR) analysis showed peaks shifting, indicating bond stretching, bond bending, and new bond formation. The Gas Chromatography-Mass Spectrometry (GC-MS) analysis revealed various new compounds produced during plastic degradation by these bacterial strains. The plastic biodegradation potential makes these bacteria an impending foundation for green chemistry to eradicate tough pollutants from the environment.

Fibrous microplastics released from textiles: Occurrence, fate, and remediation strategies

Microplastics (MP), i.e., particles measuring less than 5 mm in size, are considered emerging pollutants. The ubiquity of MP is causing great concern among environmental and public health agencies. Anthropogenic activities are responsible for the extensive dispersal of MP in nature. Adverse effects on living organisms, interactions with other contaminants occurring in the environment, and the lack of effective degradation/removal techniques are significant issues related to MP. Most MP found in nature are fibrous (FMP). FMP originate from textile products, mainly synthetic fibers (e.g., polyester). Synthetic fibers are intensively used to produce countless goods due to beneficial characteristics such as high mechanical resistance and economic feasibility. FMP are ubiquitous on the planet and impart lasting adverse effects on biodiversity. Data on the consequences of long-term exposure to these pollutants are scarce in the literature. In addition, few studies address the main types of synthetic microfibers released from textiles, their occurrence, adverse effects on organisms, and remediation strategies. This review discusses the relevant topics about FMP and alerts the dangers to the planet. Furthermore, future perspectives and technological highlights for the FMP mitigation/degradation are presented.

Consumer Awareness of Plastic: an Overview of Different Research Areas

Plastic makes our society more practical and safer. It is hard to consider eliminating plastic in some sectors, such as the medical field. However, after use, plastic waste becomes a global problem without precedents, and when not properly disposed of, it can cause several socio-environmental problems. Some possible solutions are recycling, the circular economy, proper waste management, and consumer awareness. Consumers play a crucial role in preventing problems caused by plastic. In this work, consumer awareness of plastic is discussed according to the point of view of the research areas-environmental science, engineering, and materials science-based on the analysis of the main authors' keywords obtained in a literature search in the Scopus database. Bibliometrix analyzed the Scopus search results. The results showed that each area presents different concerns and priorities. The current scenario, including the main hotspots, trends, emerging topics, and deficiencies, was obtained. On the contrary, the concerns from the literature and those of the daily lives of consumers do not seem to fit in, which creates a gap. By reducing this gap, the distance between consumers awareness and their behavior will be smaller.

The impact of plastic during the COVID-19 pandemic: The point of view of the environmental science literature

COVID-19 is the official name of the disease provoked by a coronavirus called SARS-CoV-2. Since the advent of the first cases of the new coronavirus, our society has been completely changed. Due to the changes, new environmental challenges were imposed, principally due to the considerable growth in using plastic materials in packages and personal protective equipment such as face masks. The impact of plastic during the COVID-19 pandemic was discussed in the present work from the point of view of the environmental science area. Bibliometric analysis and mapping were performed based on Scopus database search results. Emphasis was placed on analyzing the authors' keywords of the publications. The main concern of the research area concerning the use of plastic during the COVID-19 pandemic is the pollution of water bodies by plastic.

Drivers of public plastic (mis)use - New insights from changes in single-use plastic usage during the Covid-19 pandemic

The coronavirus pandemic (Covid-19) has influenced resource use and how people interact with their environment, with changing priorities and competing public health factors affecting pro-environmental behaviours at individual, societal, business and political levels. We used data from an online plastic footprint calculator to explore temporal changes, purchasing patterns and consumer behaviours around on-the-go plastic use during the pandemic. We hypothesised that 1) people's plastic use when on-the-go would change in response to the pandemic and related government restrictions and; 2) single-use plastic use on-the-go would decrease during lockdown periods due to restrictions against leaving home. The calculator received 1937 responses, with 13,544 plastic items recorded. Most used were food wrappers (54 % of all items), takeaway containers (12 %) and bottles (9 %). Six out of seven items showed increased use during lockdowns, in-line with our first hypothesis, but not the second. Three times more bottles were used, food wrapper consumption almost doubled, and takeaway container use more than doubled. Increased container use occurred alongside increased takeaway meal consumption during lockdowns. Patterns were similar between different periods of lockdown, with no significant differences in the number used of any items, or percentage of respondents using them. Results indicate that during lockdown, people found it harder to avoid single-use plastic while on-the-go, supporting evidence from other studies that plastic use can be driven by perceptions of hygiene benefits and lack of "safe" alternatives. Our results indicate opportunities to reduce single-use plastic consumption and we provide examples of successful implementation. Our findings evidence that, when properly applied, government-led guidance can effectively support consumer choices for reduced plastic use, encourage use of reusables, increase provision of alternatives, and dispel hygiene myths. The sudden increase in plastic waste due to the Covid-19 pandemic amplifies the need to substantiate plastic reduction policy promises without further delay.

Prospects of TiO2-based photocatalytic degradation of microplastic leachates related disposable facemask, a major COVID-19 waste

COVID-19 is one of the serious catastrophes that have a substantial influence on human health and the environment. Diverse preventive actions were implemented globally to limit its spread and transmission. Personnel protective equipment (PPE) was an important part of these control approaches. But unfortunately, these types of PPE mainly comprise plastics, which sparked challenges in the management of plastic waste. Disposable face masks (DFM) are one of the efficient strategies used across the world to ward off disease transmission. DFMs can contribute to micro and nano plastic pollution as the plastic present in the mask may degrade when exposed to certain environmental conditions. Microplastics (MPs) can enter the food chain and devastate human health. Recognizing the possible environmental risks associated with the inappropriate disposal of masks, it is crucial to avert it from becoming the next plastic crisis. To address this environmental threat, titanium dioxide (TiO2)-based photocatalytic degradation (PCD) of MPs is one of the promising approaches. TiO2-based photocatalysts exhibit excellent plastic degradation potential due to their outstanding photocatalytic ability, cost efficiency, chemical, and thermal stability. In this review, we have discussed the reports on COVID-19 waste generation, the limitation of current waste management techniques, and the environmental impact of MPs leachates from DFMs. Mainly, the prominence of TiO2 in the PCD and the applications of TiO2-based photocatalysts in MPs degradation are the prime highlights of this review. Additionally, various synthesis methods to enhance the photocatalytic performance of TiO2 and the mechanism of PCD are also discussed. Furthermore, current challenges and the future research perspective on the improvement of this approach have been proposed.

What makes residents more willing to participate in source separation of waste masks under the COVID-19 pandemic?

With the outbreak of the novel coronavirus (COVID-19), the generation of a large amount of medical waste brought a rude shock to the existing solid waste management system. Since masks constitute the most common household medical waste under the COVID-19 pandemic, their effective collection and treatment can significantly reduce the potential risks for secondary transmission, and this concern has attracted worldwide attention. Taking Macau City as a case study, this research tried to identify factors that can influence residents' behavioral intentions toward the source separation of COVID-19 waste masks. The extended theory of planned behavior (TPB) model is used to examine the influence factors of the source separation behaviors of 510 respondents. The results show that the main factors that positively affected respondents' behavioral intentions toward waste-mask source separation are: cognitive attitude, convenience, and perceived behavioral control, and among these, cognitive attitude has the highest influence. Subjective norm is also proved to be the weak factor to improving behavioral intention. Policy advocacy, and demographic variables have no significant effect on behavioral intention. The results of this study can help decision makers and managers formulate effective strategies to increase residents' participation in the source separation of waste masks.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10163-022-01513-7.

The impact of COVID-19 on the sustainability of the environment, animal health and food security, and safety

COVID-19 pandemic influenced the environment, animal health, and food security. Due to reduced human mobility, the air and water quality increased. Other environmental consequences were the personal protective types of equipment and their haphazard disposal. Atmospheric pollution could be a cofactor leading to an increased COVID-19 mortality rate. Lockdown, however, caused a reduction in air and water pollution. Noise pollution affects the health of individuals and communities in terms of cardiovascular disorders and sleeping problems. Meanwhile, the COVID-19 lockdown controls human activities that reduce noise pollution. Municipal waste affects the environment. Recycling has been reduced in some countries but not in Saudi Arabia. COVID-19 had a drastic effect on livestock production on national, regional, and global levels, affecting countries' capacities to prevent and control diseases of animals and increasing global poverty, becoming a threat to the sustainability of global food security and safety. Many lessons have been learned from the COVID-19 pandemic, so it is wise to study and analyze the previous lessons and shed some light on past pandemics such as the Spanish flu to understand the readings and earn experiences. This paper is focused on the interaction between the pandemic and environmental health from the public health concern rather than other health classifications.

Recycling of plastic wastes generated from COVID-19: A comprehensive illustration of type and properties of plastics with remedial options

Plastic has contributed enormously to the healthcare sector and towards public health safety during the COVID-19 pandemic. With the frequent usage of plastic-based personal protective equipment (PPEs) (including face masks, gloves, protective body suits, aprons, gowns, face shields, surgical masks, and goggles), by frontline health workers, there has been a tremendous increase in their manufacture and distribution. Different types of plastic polymers are used in the manufacture of this equipment, depending upon their usage. However, since a majority of these plastics are still single-use plastics (SUP), they are not at all eco-friendly and end up generating large quantities of plastic waste. The overview presents the various available and practiced methods in vogue for disposal cum treatment of these highly contaminated plastic wastes. Among the current methods of plastic waste disposal, incineration and land filling are the most common ones, but both these methods have their negative impacts on the environment. Alongside, numerous methods that can be used to sterilize them before any treatment have been discussed. There are several new sorting technologies, to help produce purer polymers that can be made to undergo thermal or chemical treatments. Microbial degradation is one such novel method that is under the spotlight currently and being studied extensively, because of its ecological advantages, cost-effectiveness, ease of use, and maintenance. In addition to the deliberations on the methods, strategies have been enumerated for combination of different methods, vis-à-vis studying the life cycle assessment towards a more circular economy in handling this menace to protect mankind.

A Perspective of the COVID-19 Pandemic in the Plastic Waste Management and Cooperatives of Waste Pickers in Brazil

Brazil is the fourth largest producer of plastic waste in the world. Among all the challenges the country had faced in the development of public policies for the banning of single-use plastics, the new coronavirus pandemic scenario determined the suspension of these laws indefinitely. In 2020, Brazil became the global epicenter of COVID-19. This scenario changed the habit and behavior of Brazilian consumers, who increased the consumption of plastics due to their importance in applications as protective material. The country also has social problems related to waste management that depend mainly on waste pickers. These workers need social visibility and protection not only to face the current health crisis but also to guarantee their income and survival. This work aims to discuss the increase in single-use plastics that are not intended for recycling and the respective environmental, economic, and social impacts for the country. We demonstrate the lack of data on waste management in Brazil and highlight the importance of the social inclusion of waste pickers for a circular economy. Especially after the change of scenario with the COVID-19 pandemic, the country must have adequate planning and improvements in waste management, recycling programs, and political intervention to raising awareness among the population and guaranteeing social rights for waste pickers.

Tertiary amines convert 1O2 to H2O2 with enhanced photodynamic antibacterial efficiency

Photodynamic inactivation (PDI) is a promising approach to combat the increasing global multi-drug resistance crisis. However, the very short half-life of ¹O₂ and the inevitable photobleaching of photosensitizer (PS) are the inherent drawbacks that largely compromise its therapeutic efficiency. Here, we report a ROS conversion strategy that simultaneously addresses these issues. Based on a photodynamic model system where riboflavin (RF) served as the PS, we have clearly shown that about 93.2% of ¹O₂ could be converted to hydrogen peroxide (H₂O₂) in the presence of tertiary amine. The less reactivity of H₂O₂ (v.s.¹O₂) could retard the photobleaching of riboflavin by 88.9%. Orders of magnitude extended half-life of ROS (H₂O₂v.s.¹O₂) and retarded photobleaching of RF synergistically provide a more persistent oxidization that increased the oxidation capacity of the photodynamic model system by 56.6%. Consequently, it is able to improve the therapeutic efficiencies from 89.6% to 99.1% in combating methicillinresistant S. aureus (MRSA) and from 64.0% to 92.0% in eradicating S. aureus biofilm on biomaterials within a 5-min simulated sunlight illumination. The reinforced photodynamic model system could also significantly accelerate the healing & maturing of MRSA infected skin wound as compared to that of clinically used vancomycin. The generality of "ROS conversion" among different amines and different photosensitizers have been verified. These findings may inspire many creative approaches to increase the antibacterial efficiency of current photodynamic treatments for diverse applications.

Toxic impact of polystyrene microplastic particles in freshwater organisms

The ongoing COVID-19 pandemic is leading to an increase of the global production of plastics since the use of personal protective equipment (PPEs, i.e. gloves, gowns, masks, packaging items), has become mandatory to prevent the spread of the virus. Plastic breaks down into micro/nano particles due to physical or chemical or biological actions into environment. Due to small dimensions, ubiquitous and persistent nature, the plastic particles represent a significant threat to ecosystems and can entry into food chains. Among the plastic polymers used for PPEs, polystyrene is less studied regarding its eco-geno-toxicity. This study aims to investigate acute, chronic and subchronic effects of the microplastic polystyrene beads (PS-MP, size 1.0 μm) on three freshwater species, the alga Raphidocelis subcapitata, the rotifer Brachionus calyciflorus, the crustacean Ceriodaphnia dubia and the benthic ostracod Heterocypris incongruens. Furthermore, the potential genotoxicity and the ROS production due to the PS-MP were also determined in C. dubia. Results revealed that the acute effects occurred at concentrations of PS-MP in the order of dozens of mg/L in B. calyciflorus and C. dubia and hundreds of mg/L in H. incongruens. Regarding long-term toxicity, increasing chronic effects with EC50s in the order of units (C. dubia), hundreds (B. calyciflorus) and thousands (R. subcapitata) of μg/L were observed. Both for acute and chronic/sub chronic toxicity, daphnids were more sensitive to polystyrene than ostracods. Moreover, when C. dubia neonates were exposed to the PS-MP, alterations in genetic material as well as the production of ROS occurred, starting from concentrations in the order of units of μg/L, probably due to inflammatory responses. At last, the risk quotient (RQ) as a measure of risk posed by PS-MPs in freshwater environment, was calculated obtaining a value of 7.2, higher than the threshold value of 1.

The COVID-19 pandemic reshapes the plastic pollution research - A comparative analysis of plastic pollution research before and during the pandemic

The outbreak of the COVID-19 pandemic has exacerbated plastic pollution worldwide. So has the COVID-19 pandemic changed the research on plastic pollution? This work aims to explore the impact of the pandemic on plastic pollution research by comprehensively assessing the current status and prospects of plastic pollution research before and during the COVID-19 pandemic. A collection of publications on the topic of plastic pollution in the Web of Science database concludes that the COVID-19 pandemic has reshaped the plastic pollution research: (i) The COVID-19 pandemic has changed the trend of plastic pollution publication output. Since the COVID-19 pandemic, the number of publications on the topic of plastic pollution has shown a significant increase trend; (ii) The COVID-19 pandemic has reversed the global research landscape of research on the plastic pollution. Since the outbreak of the pandemic, more and more countries have begun to pay attention to plastic pollution. Before the pandemic, developed countries were global leaders in plastic pollution research. However, during the pandemic, developing countries began to have a significant share in the quality, quantity and international cooperation of publications; (iii) The COVID-19 pandemic has redefined the major hotspots of plastic pollution research. The focus of research has changed significantly since the pandemic. Solving plastic pollution has become a major research content. During the epidemic, in-depth research on microplastics was conducted. The results of mining the publications on plastic pollution show that there is currently no effective solution to plastic pollution caused by the COVID-19. However, given the seriousness of controlling plastic pollution, it is very necessary to continue to carry out more research.

Towards a Circular Economy of Plastics: An Evaluation of the Systematic Transition to a New Generation of Bioplastics

Plastics have become an essential part of the modern world thanks to their appealing physical and chemical properties as well as their low production cost. The most common type of polymers used for plastic account for 90% of the total production and are made from petroleum-based nonrenewable resources. Concerns over the sustainability of the current production model and the environmental implications of traditional plastics have fueled the demand for greener formulations and alternatives. In the last decade, new plastics manufactured from renewable sources and biological processes have emerged from research and have been established as a commercially viable solution with less adverse effects. Nevertheless, economic and legislative challenges for biobased plastics hinder their widespread implementation. This review summarizes the history of plastics over the last century, including the most relevant bioplastics and production methods, the environmental impact and mitigation of the adverse effects of conventional and emerging plastics, and the regulatory landscape that renewable and recyclable bioplastics face to reach a sustainable future.

Binational survey of personal protective equipment (PPE) pollution driven by the COVID-19 pandemic in coastal environments: Abundance, distribution, and analytical characterization

In the present contribution, two nationwide surveys of personal protective equipment (PPE) pollution were conducted in Peru and Argentina aiming to provide valuable information regarding the abundance and distribution of PPE in coastal sites. Additionally, PPE items were recovered from the environment and analyzed by Fourier transformed infrared (FTIR) spectroscopy, Scanning electron microscopy (SEM) with Energy dispersive X-ray (EDX), and X-ray diffraction (XRD), and compared to brand-new PPE in order to investigate the chemical and structural degradation of PPE in the environment. PPE density (PPE m^-2) found in both countries were comparable to previous studies. FTIR analysis revealed multiple polymer types comprising common PPE, mainly polypropylene, polyamide, polyethylene terephthalate, and polyester. SEM micrographs showed clear weathering signs, such as cracks, cavities, and rough surfaces in face masks and gloves. EDX elemental mapping revealed the presence of elemental additives, such as Ca in gloves and face masks and AgNPs as an antimicrobial agent. Other metals found on the surface of PPE were Mo, P, Ti, and Zn. XRD patterns displayed a notorious decrease in the crystallinity of polypropylene face masks, which could alter its interaction with external contaminants and stability. The next steps in this line of research were discussed.

Microplastic Extraction from the Sediment Using Potassium Formate Water Solution (H2O/KCOOH)

Microplastics (MPs) are considered an important stratigraphic indicator, or ‘technofossils’, of the Anthropocene. Research on MP abundance in the environment has gained much attention but the lack of a standardized procedure has hindered the comparability of the results. The development of an effective and efficient method of MP extraction from the matrix is crucial for the proper identification and quantifying analysis of MPs in environmental samples. The procedures of density separation used currently have various limitations: high cost of reagents, limited solution density range, hazardous reagents, or a combination of the above. In this research, a procedure based on density separation with the use of potassium formate water solution (H2O/KCOOH) in controlled conditions was performed. Experimental sediment mixtures, spiked with polyethylene (PE), polystyrene (PS), polyurethane (PUR) and polyethylene terephthalate (PET) particles were prepared and an extraction procedure was tested in the context of a weight-based quantitative analysis of MPs. This article discusses the effectiveness and safety of the method. It additionally provides new information on the interactions between MP particles and the mineral matter of the sediment. Results were acquired with the use of instrumental methods, namely thermogravimetry (TG), Fourier Transform Infrared (FTIR) spectroscopy, Field Emission Scanning Electron microscopy and Energy Dispersive spectrometry (SEM/EDS), as well as X-ray fluorescence (XRF) analysis.

Nanocarriers for Sustainable Active Packaging: An Overview during and Post COVID-19

Lockdown has been installed due to the fast spread of COVID-19, and several challenges have occurred. Active packaging was considered a sustainable option for mitigating risks to food systems during COVID-19. Biopolymeric-based active packaging incorporating the release of active compounds with antimicrobial and antioxidant activity represents an innovative solution for increasing shelf life and maintaining food quality during transportation from producers to consumers. However, food packaging requires certain physical, chemical, and mechanical performances, which biopolymers such as proteins, polysaccharides, and lipids have not satisfied. In addition, active compounds have low stability and can easily burst when added directly into biopolymeric materials. Due to these drawbacks, encapsulation into lipid-based, polymeric-based, and nanoclay-based nanocarriers has currently captured increased interest. Nanocarriers can protect and control the release of active compounds and can enhance the performance of biopolymeric matrices. The aim of this manuscript is to provide an overview regarding the benefits of released active compound-loaded nanocarriers in developing sustainable biopolymeric-based active packaging with antimicrobial and antioxidant properties. Nanocarriers improve physical, chemical, and mechanical properties of the biopolymeric matrix and increase the bioactivity of released active compounds. Furthermore, challenges during the COVID-19 pandemic and a brief post-COVID-19 scenario were also mentioned.

Genotoxic effect of microplastics and COVID-19: The hidden threat

Microplastics (MPs) are ubiquitous anthropogenic contaminants, and their abundance in the entire ecosystem raises the question of how far is the impact of these MPs on the biota, humans, and the environment. Recent research has overemphasized the occurrence, characterization, and direct toxicity of MPs; however, determining and understanding their genotoxic effect is still limited. Thus, the present review addresses the genotoxic potential of these emerging contaminants in aquatic organisms and in human peripheral lymphocytes and identified the research gaps in this area. Several genotoxic endpoints were implicated, including the frequency of micronuclei (MN), nucleoplasmic bridge (NPB), nuclear buds (NBUD), DNA strand breaks, and the percentage of DNA in the tail (%Tail DNA). In addition, the mechanism of MPs-induced genotoxicity seems to be closely associated with reactive oxygen species (ROS) production, inflammatory responses, and DNA repair interference. However, the gathered information urges the need for more studies that present environmentally relevant conditions. Taken into consideration, the lifestyle changes within the COVID-19 pandemic, we discussed the impact of the pandemic on enhancing the genotoxic potential of MPs whether through increasing human exposure to MPs via inappropriate disposal and overconsumption of plastic-based products or by disrupting the defense system owing to unhealthy food and sleep deprivation as well as stress. Overall, this review provided a reference for the genotoxic effect of MPs, their mechanism of action, as well as the contribution of COVID-19 to increase the genotoxic risk of MPs.

Microplastics as contaminants in Indian environment: a review

The increased production and consumption scale of plastic items has led to the generation of microplastics (MPs), an emerging class of contaminants, in our environment. MPs are plastic particles less than 5 mm in size and could originate due to primary and secondary sources. The primary ones are generated as such in the MP size range while the secondary MPs are a result of fragmentation of larger plastic particles which eventually enters the aquatic, terrestrial and atmospheric environments. The increasing concern of MP pollution in every compartment of our environment is being globally explored, with relatively fewer studies in India. Among the total studies published on MP prevalence in the Indian environments, marine systems have received significantly higher attention compared to the other compartments like freshwater, atmosphere, terrestrial and human consumables. This review article is an effort to present current understanding of MP pollution in aquatic systems, terrestrial systems, atmosphere and human consumables of India by reviewing available scientific literature. Along with this, the review also focuses on identification of the gap areas in current knowledge and highlights way forward for future research. This would further help in meeting the goals of this emergent pollutant management.