Comparison of different salt solutions for density separation of conventional and biodegradable microplastic from solid sample matrices

Emerging isolation and degradation technology of microplastics and nanoplastics in the environment

Microplastics (MPs, less than 5 mm in size) are widely distributed in surroundings in various forms and ways, and threaten ecosystems security and human health. Its environmental behavior as pollutants carrier and the after-effects exposed to MPs has been extensively exploited; whereas, current knowledge on technologies for the separation and degradation of MPs is relatively limited. It is essential to isolate MPs from surroundings and/or degrade to safe levels. This in-depth review details the origin and distribution of MPs. Provides a comprehensive summary of currently available MPs separation and degradation technologies, and discusses the mechanisms, challenges, and application prospects of these technologies. Comparison of the contribution of various separation methods to the separation of NPs and MPs. Furthermore, the latest research trends and direction in bio-degradation technology are outlooked.

Characterizing the Microplastic Content of Biosolids in Southern Ontario, Canada

The application of biosolids to agricultural land has been identified as a major pathway of microplastic (MP) pollution to the environment. Very little research, however, has been done on the MP content of biosolids within Canada. Fifteen biosolid samples from different treatment processes (liquid, dewatered, pelletized, and alkali-stabilized) were collected from 11 sources across southern Ontario to quantify and characterize the MP load within them. All samples exhibited MP concentrations ranging from 188 200 (±24 161) to 512 000 (±28 571) MPs/kg dry weight and from 4122 (±231) to 453 746 (±38 194) MPs/kg wet weight. Field amendment of these biosolids can introduce up to 3.73 × 106 to 4.12 × 108 MP/ha of agricultural soil. There was no significant difference in the MP concentrations of liquid, dewatered, and pelletized samples; but a reduction in MP content was observed in alkali-stabilized biosolids. Fragments composed 57.6% of the MPs identified, while 36.7% were fibers. In addition, MPs showed an exponential increase in abundance with decreasing size. Characterization of MPs confirmed that polyester was the most abundant, while polyethylene, polypropylene, polyamide, polyacrylamide, and polyurethane were present across the majority of biosolid samples. The results of the present study provide an estimate of the potential extent of MP contamination to agricultural fields through the amendment of biosolids. Environ Toxicol Chem 2024;00:1-14. © 2023 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.

Recent advances on the methods developed for the identification and detection of emerging contaminant microplastics: a review

The widespread use of plastics, popular for their versatility and cost-efficiency in mass production, has led to their essential role in modern society. Their remarkable attributes, such as flexibility, mechanical strength, lightweight, and affordability, have further strengthened their importance. However, the emergence of microplastics (MPs), minute plastic particles, has raised environmental concerns. Over the last decade, numerous studies have uncovered MPs of varying sizes in diverse environments. They primarily originate from textile fibres and cosmetic products, with large plastic items undergoing degradation and contributing as secondary sources. The bioaccumulation of MPs, with potential ingestion by humans through the food chain, underscores their significance as environmental contaminants. Therefore, continuous monitoring of environmental and food samples is imperative. A range of spectroscopic techniques, including vibrational spectroscopy, Raman spectroscopy, Fourier-transform infrared (FT-IR) spectroscopy, hyperspectral imaging, and nuclear magnetic resonance (NMR) spectroscopy, facilitates the detection of MPs. This review offers a comprehensive overview of the analytical methods employed for sample collection, characterization, and analysis of MPs. It also emphasizes the crucial criteria for selecting practical and standardized techniques for the detection of MPs. Despite advancements, challenges persist in this field, and this review suggests potential strategies to address these limitations. The development of effective protocols for the accurate identification and quantification of MPs in real-world samples is of paramount importance. This review further highlights the accumulation of microplastics in various edible species, such as crabs, pelagic fish, finfish, shellfish, American oysters, and mussels, shedding light on the extreme implications of MPs on our food chain.

Microplastics pollution in rice fields: a case study of Pir Bazar rural district of Gilan, Iran

Various stressors threaten rice fields' productivity. Microplastics (MPs) are ubiquitous pollutants that accumulate in agricultural soils, effectively impairing agroecosystem functioning. The study investigates the MPs pollution status of rice fields and compares it with that of non-paddy vegetable farms under contrasting management practices. Possible sources of MPs in the fields are identified. Additionally, the relationships between MPs abundance and soil characteristics are investigated. This provides innovative insights into the possible impact of MPs on soil health and functioning. Density separation using saturated NaCl solution and oxidative organic matter digestion using Fenton's reagent were employed to extract the MPs. The extracted MPs were categorized according to shape, size, and color. The results indicated that the paddies (1952.86±114.36 particles/kg) contained significantly more MPs than did the non-paddies (1134.44±221.52 particles/kg). Beads (53.75%) and fibers (28.46%) were the most common MPs. More than 90% of all MPs recovered from the fields were less than 1 mm in size. Of the 16 color groups identified, the colors silver, white, and black were the most abundant. Sewage sludge application and mulching were recognized as the primary sources of MPs in the paddies, with sludge contributing more than mulching. Microplastics were shown to potentially alter vital soil characteristics. Rice fields are otherwise overlooked reservoirs of MPs. More attention should be paid to raising awareness of their role as MPs accumulation hotspots among governmental bodies, researchers, producers, and citizens. Contributing MPs sources need to be identified, and managerial decisions should consider the polluting capacity of different practices.