Unveiling the noxious effect of polystyrene microplastics in aquatic ecosystems and their toxicological behavior on fishes and microalgae

Accumulation of microplastic in edible marine species from North Kerala, India

Microplastics in edible seafood constitute a significant concern, as they can accumulate in the tissues of marine organisms and entering food chain through which it reaches human and cause health risks. This study aims to investigate the presence of microplastics in the edible tissues of Marcia opima, Metapenaeus dobsoni, and Stolephorus indicus, collected from the central fish markets in Kasargod District of Kerala, India. About 9 kg of seafood (3 kg of each species) was collected from three major fish markets. From this, 50 species samples were randomly selected, totalling 150 samples representing each sample. About 193 microplastics from 150 individuals of three different seafood species were isolated and identified. Metapenaeus dobsoni was found to have the greatest number of microplastics (155) among these three species. Microplastic fibres constituted a significant part of total microplastic counts. Microplastic identification was made using a 'Leica stereo-zoom binocular microscope'; confirmation and polymer identification were made using the FTIR-ATR method. Six different polymers were identified such as polyethylene, polyethylene terephthalate, polyvinyl chloride, polyester, polytetrafluoroethylene, and polyacrylamide. Among these, microplastic analysis across all three species showed that nearly half were composed of polyethylene, with polyethylene terephthalate being the second most prevalent polymer. Additionally, Metapenaeus dobsoni has been newly reported globally as a species with microplastic contamination.

Microplastic pollution in marine environments: An in-depth analysis of advanced monitoring techniques, removal technologies, and future challenges

Microplastics, recognized as toxic contaminants, have pervaded terrestrial, atmospheric, and marine environments, transitioning from emerging pollutants to pervasive threats. About 10 % of the plastic produced worldwide enters into the ocean which constitutes 85 % of marine litter. Microplastic distribution holds the highest concentration in the Atlantic Ocean whereas the Southern Ocean holds the lowest. Concerning microplastics, reports state that each year about 1.3 million metric tons of microplastics enter the ocean. The microparticles account for about 90 % of the floating ocean debris and over 75 % of these particles originate from land-based sources which include urban runoff, and mismanaged wastes. This review offers a thorough examination of the sources of microplastics and their environmental consequences and ecological impacts. The ubiquity of microplastics necessitates robust control measures, starting with their monitoring and detection in aquatic ecosystems to assess the effectiveness of mitigation strategies. Current removal methods, including physical, chemical, and bio-based techniques, are detailed, alongside advances in filtration, separation, and integrated hybrid approaches for microplastic control. The review concludes with perspectives on the limitations of existing methods and directions for future research in microplastic monitoring, detection, and removal.

Size, shape, and elemental composition as predictors of microplastic surface erosion

The degradation of surfaces and its possible dependence on shape, size, and elemental composition of plastic particles were subjected. The surfaces of 146 microplastics were classified from smooth to fully eroded (%) by SEM/EDS. Structural elements and various additives were found on microplastics depending on their shapes. The surface of plastic items > 100 µm in length showed a relatively more eroded area than smaller ones, regardless of their shapes. Depending on shape, the percentage of surface erosion of irregularly shaped fragments < 100 µm was significantly enhanced compared to microbeads of the same size. These results may provide insights into assessing potential risks posed by microplastics and improve our understanding of the role of these parameters concerning possible adverse health effects on the environment.

Identification Tools of Microplastics from Surface Water Integrating Digital Image Processing and Statistical Techniques

The primary objective of this study was to demonstrate the potential of digital image analysis as a tool to identify microplastic (MP) particles in surface waters and to facilitate their characterisation in terms of 2D and 3D morphology. Digital image analysis preceded by microscopic analysis was used for an exhaustive quantitative and qualitative evaluation of MPs isolated from the Vistula River. Using image processing procedures, 2D and 3D shape descriptors were determined. Principal Component Analysis was used to interpret the relationships between the parameters studied, characterising MP particle geometry, type and colour. This multivariate analysis of the data allowed three or four main factors to be extracted, explaining approximately 90% of the variation in the data characterising MP morphology. It was found that the first principal component for granules, flakes and films was largely represented by strongly correlated with 2D shape descriptors (area, perimeter, equivalent area diameter) and 3D shape descriptors (Corey Shape Factor, Compactness, Dimensionality). Considering the scraps, principal component PC1 was represented by only five of the above descriptors, and the Compactness variable had the largest contribution to principal component PC2. In addition, for granules, flakes and films, a relationship between 2D shape and the colour of their particles could be observed. For the most numerous MP group identified of multicoloured scraps, no such association was found. The results of our study can be used for further multivariate analysis regarding the presence of microplastic floating on the river surface, with a particular focus on particles of secondary origin. This is of key importance for optimising future efforts in conducting small-scale and multidimensional monitoring of and reducing plastics in the aquatic environment.

Mitigating microplastic pollution: A critical review on the effects, remediation, and utilization strategies of microplastics

Microplastics are found ubiquitous in the natural environment and are an increasing source of worry for global health. Rapid industrialization and inappropriate plastic waste management in our daily lives have resulted in an increase in the amount of microplastics in the ecosystem. Microplastics that are <150 μm in size could be easily ingested by living beings and cause considerable toxicity. Microplastics can aggregate in living organisms and cause acute, chronic, carcinogenic, developmental, and genotoxic damage. As a result, a sustainable approach to reducing, reusing, and recycling plastic waste is required to manage microplastic pollution in the environment. However, there is still a significant lack of effective methods for managing these pollutants. As a result, the purpose of this review is to convey information on microplastic toxicity and management practices that may aid in the reduction of microplastic pollution. This review further insights on how plastic trash could be converted as value-added products, reducing the load of accumulating plastic wastes in the environment, and leading to a beneficial endeavor for humanity.