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The pervasiveness of microplastics in aquatic ecosystems has become a major environmental issue in recent years. The gradual dumping of plastic wastes, inadequate standard detection methods with specific removal techniques, and slow disposal rate of microplastics make it ubiquitous in the environment. Evidence shows that microplastics act as a potential vector by adsorbing different heavy metals, pathogens, and other chemical additives widely used in different raw plastic production. Microplastics are ingested by aquatic creatures such as fish and different crustaceans, and finally, people ingest them at the tertiary level of the food chain. This phenomenon is responsible for blocking the digestion tracts, disturbing the digestive behavior, finally decreasing the reproductive growth of entire living organisms. Because of these consequences, microplastics have become an increasing concern as a newly emerging potential threat, and therefore, the control of microplastics in aquatic media is required. This paper provides a critical analysis of existing and newly developed methods for detecting and separating microplastics from discharged wastewater, which are the ultimate challenges in the microplastic treatment systems. A critical study on the effect of microplastics on aquatic organisms and human health is also discussed. Thus, this analysis provides a complete understanding of entire strategies for detecting and removing microplastics and their associated issues to ensure a waste discharge standard to minimize the ultimate potential impact in aquatic environments. Graphical abstract

Polyethylene has considered as non-degradable for decades, and their degradation through marine bacteria has rarely studied. However, LDPE found a significant source of pollution in the marine environment. In the present study, four bacterial strains capable of biodegradation of LDPE were isolated from the marine environment. These bacterial isolates H-237, H-255, H-256 and H-265 were revealed close similarity with Cobetia sp., Halomonas sp., Exigobacterium sp. and Alcanivorax sp., respectively based on 16S rRNA gene sequencing method. These bacterial isolates were individually incubated for 90 days supplied with LDPE films as a carbon source using the Bushnell-Haas medium. During the biodegradation assay, bacterial isolates were formed the viable biofilm on the LDPE surface, which decreased the thermal stability of the films. At the end of the incubation study, a maximum weight loss of 1.72% of LDPE film was observed by the bacterial isolate H-255. The bacterial attachment on the film changed the physical structure (surface erosion, roughness and degradation) which were confirmed by field emission scanning electron microscopy and atomic force microscopy. The changes in the chemical structure of the LDPE film were analyzed by Attenuated total reflection Fourier-transform infrared spectroscopy (ATR-FTIR). This ATR-FTIR showed the shifting of peaks of C–H stretch and C=C bond stretching and the new peaks formation of C–O and –C=C– bonds in comparison to control LDPE film. Further, biodegradation of LDPE film was also confirmed by remineralization of carbon and enzymatic activities. This study revealed that the active biodegradation of LDPE film by marine bacteria and these bacteria could reduce plastic pollution in the marine environment.

This study reports the contamination of Indian sea salts with different microplastic particles, as a consequence of using contaminated sea water. Samples from all eight brands of investigated sea salts were found contaminated, and concentrations of these particles ranged from 103 ± 39 to 56 ± 49 particles kg −1 of salt. Both fibers and fragments were observed with large variation in size. Eighty percent of the extracted fibers and the fragments were smaller than 2000 μm and 500 μm respectively. Extracted particles were mostly polyesters, polyethylene terephthalate (PET), polyamide, polyethylene, and polystyrene. Their total mass concentration was also estimated as 63.76 μg kg −1 of salt. These results are significant, since India is a leading producer and exporter of sea salts. A simple sand filtration of artificially contaminated sea water could effectively (> 85% removal by weight and > 90% removal by number) remove these microplastics and has the potential for preventing the transfer of microplastics into the salt from contaminated sea waters.

This study examines the distribution, abundance and characteristics of surface micro- and mesoplastic debris in the Western Mediterranean Sea. 41 samples were collected in 2011 (summer) and 2012 (summer). Results, firstly, revealed that micro- (<5 mm) and mesoplastic debris were widely and uniformly distributed in this area with average concentrations of 130,000 parts/km 2 and 5700 parts/km 2 , respectively. Importantly, a strong correlation between micro- and mesoplastic concentrations was identified. Secondly, a classification based on the shape and appearance of microplastics indicated the predominant presence of fragments (73 %) followed by thin films (14 %). Thirdly, the average mass ratio of microplastic to dry organic matter has been measured at 0.5, revealing a significant presence of microplastics in comparison to plankton. Finally, a correction method was applied in order to correct wind mixing effect on microplastics’ vertical distribution. This data allows for a comprehensive view, for the first time, of the spatial distribution and nature of plastic debris in the Western Mediterranean Sea.

Marine pollution is a significant issue in recent decades, with the increase in industries and their waste harming the environment and ecosystems. Notably, the rise in shellfish industries contributes to tons of shellfish waste composed of up to 58% chitin. Chitin, the second most ample polymer next to cellulose, is insoluble and resistant to degradation. It requires chemical-based treatment or enzymatic hydrolysis to cleave the chitin polymers. The chemical-based treatment can lead to environmental pollution, so to solve this problem, enzymatic hydrolysis is the best option. Moreover, the resulting biopolymer by-products can be used to boost the fish immune system and also as drug delivery agents. Many marine microbial strains have chitinase producing ability. Nevertheless, we still lack an economical and highly stable chitinase enzyme for use in the industrial sector. So we isolate a novel marine bacterial strain Achromobacter xylosoxidans from the shrimp waste disposal site using chitin minimal medium. Placket–Burman and central composite design statistical models for culture condition optimisation predicted a 464.2 U/ml of chitinase production. The culture conditions were optimised for maximum chitinase production recording up to 467 U/ml. This chitinase from the A. xylosoxidans was 100% active at an optimum temperature of 45 °C (withstand up to 55 °C) and pH 8 with 80% stability. The HPLC analysis of chitinase degraded shellfish waste reveals a major amino acid profile composition—arginine, lysine, aspartic acid, alanine, threonine and low levels of isoleucine and methionine. These chitinase degraded products and by-products can be used as supplements in the aquaculture industry.

In today’s world, marine pollution is becoming more and more serious, and the protection of marine ecosystems and endangered marine organisms has become an important international issue. In 2012, the blue whale was officially listed on the IUCN Red List of Threatened Species. As the top predator in the ocean, blue whales are seeing a drastically decreasing population, which will break the ecological balance of the region. The interlocked food chain in the ocean means it would eventually lead to the forming of an “ocean desert”. Therefore, it is urgent to start the popularization of science to protect the endangered marine organisms for the public. Based on human-computer interaction and sound visualization, the author designs an interactive installation with the theme of “The Last Whale Sound”, aiming to increase the public’s attention to endangered marine organisms, to arouse people’s self-reflection and environmental awareness, and to make the public consciously participate in protecting marine ecosystems.

Microplastics have caused considerable harm to the environment and threatened human health due to their strong adsorption and hard biodegradation. Therefore, the research of microplastic received increasing attention recently, producing numbers of related achievements. To comprehensively grasp the quantitative information of published papers on “microplastics,” we analyzed the research progress and hotspots of “microplastics” through visualization software “VOSviewer.” The results show that the number of literature on microplastics published from 2009 to 2019 increased exponentially ( R 2  = 0.9873). The top 10 cited references are mainly in “zooplankton ingesting microplastics,” “microplastics in artificially cultivated bivalve,” “microplastics in surface waters such as lakes,” etc. The cutting-edge microplastics research is adsorption, biodegradation, ingestion and accumulation model, and toxicity analysis. In addition, the results predict that the combination of constructed wetland, biotechnology, and photocatalysis to remove microplastics will become new hotspots. The study provides researchers in microplastics with an overview of existing research and directional guidance for future research.

PurposeThe increasing global concern surrounding plastic pollution has resulted in a spotlight being placed on major contributors. Straws have been identified as a top contributor in this regard leading to a global outcry against plastic straws. This has resulted in the increasing popularity of plastic straw material alternatives. This study compares the environmental impacts associated with five straw material options available in South Africa.MethodsThe straw materials compared include disposable options (polypropylene, paper and polylactide) and reusable straws (glass and steel). Plastic straws were the only option which are locally produced from local materials, whereas glass and steel straws are manufactured from imported materials and paper and polylactide straws are imported. The functional unit was based on an annual straw consumption per capita, which equates to 36 disposable straws and 1 reusable straw. The impact assessment was conducted using the Recipe Midpoint (H) method, which took into consideration 18 impact categories. The potential marine pollution impacts were explored based on the leakage propensity of the material option coupled with its degradability.Results and discussionThe paper straw was found to have lower climate change emissions than the plastic one, which was mainly caused by the performance of the material. In South Africa, coal is used as a primary feedstock for polypropylene production making it more carbon-intensive in comparison with polypropylene produced in Europe and the USA which is primarily from crude oil and/or natural gas feedstocks. Glass and steel straws would require 23–39 and 37–63 uses respectively to break even with climate change emissions associated with disposable options. Overall, material production was the major contributor to straw emissions. The relative contribution of transportation, including import, was more dependent on the transportation mode compared with distance. For reusable straws, the washing water temperature was found to notably influence emissions. At end-of-life, reusable straws were considered unlikely to enter the marine environments. Disposable straws were found to have a leakage rate of 38%, with paper being the only marine degradable material.ConclusionsOverall, paper straws had the least impacts in the majority of impact categories in comparison with other disposable options and glass was more favourable to steel. In terms of marine pollution, reusable straws were deemed to pose the least risk due to their unlikelihood to be polluted. Paper was associated with the least potential impacts of the disposal options, due to its degradability.

Drawing from literary criticism and institutional theory, this article analyzes the public discourse surrounding the Exxon Valdez spill of 1989 and BP Gulf Spill of 2010. While industrial accidents such as oil spills can erode consumers’ trust in experts, a macrolevel analysis reveals that media coverage of such events ultimately contains the anxieties that are sparked by initial news coverage. The brandcentric disaster myths generated by media coverage frame public discourse in ways that help to reestablish consumers’ trust in expert systems while also insulating corporations and governmental institutions from more systematic critiques. This analysis contributes to a macrolevel theorization of the institutional and ideological structures that shape consumers’ risk perceptions and just world beliefs. It also extends prior accounts of cultural branding by identifying a set of ideological effects that operate in concert with the more commonly discussed therapeutic benefits afforded by marketplace myths.

The Medellin Declaration on Marine Litter in Life Cycle Assessment and Management was developed during the Conferencia Internacional de Análisis de Ciclo de Vida en Latinoamérica, which took place from 12–15 June in Medellin, Colombia. The Declaration calls for an improved handling of plastic resources and is meant to encourage researchers and relevant stakeholders to develop new methodologies to address marine litter better within Life Cycle Assessments. The declaration has been co-authored by various stakeholders present at the conference and has been revised in an online-consultation process until the 18th of July. The global life cycle community is invited to join the Medelling Declaration, which is available for signature on the FSLCI website at: https://fslci.org/medellindeclaration .