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The impact of adding ethylene vinyl acetate copolymer (EVA 80) and 1 wt% TiO 2 nanoparticles on the morphology and crystallization behavior of poly(lactic acid) blends was investigated using DSC, SEM, and POM. Thermal analysis revealed the enhancement of crystallinity of PLA in the presence of TiO 2 and higher EVA 80 content in the blend. The PLA and EVA 80 components showed compatibility, as evidenced by the shift of the glass transition temperatures of the PLA phase in the blend to lower values compared to neat PLA. The lower temperature shift of the cold crystallization of the PLA and the formation of the small spherulites of the PLA in the blends indicated that the EVA 80 and TiO 2 act as a nucleating agent for crystallization. The non-isothermal crystallization parameters of the composites were evaluated using Avrami's modified model, the MO approach, and Friedman’s isoconversional method. The Avrami’s modified rate constant (K) and the effective activation energy values significantly increased with the incorporation of EVA 80 and TiO 2 nanoparticles. Furthermore, the thermogravimetric analysis (TGA) showed improved thermal stability of PLA by adding EVA 80 and TiO 2 .

Currently, plastic pollutants in the aquatic environment have received much attention. The studies on the abundance of microplastics in the river system are consequently lower compared to the studies on the marine system. The study aimed to determine the abundance of microplastics in water and riverbank sediments of Miri River and classify their spatial distribution patterns. In this study, water and sediment samples were collected from five sampling points in Miri River to investigate the abundance and distribution of microplastics as well as the characteristics of microplastics in Miri River. The abundance of microplastics in water samples was within the range of 0.8 to 2.1 mg/L or 10.7 to 14.3 particle /L. In sediment samples, the abundance of microplastics was within the range of 26.2 to 62.5 mg/kg or 283.7 to 456.2 particle/kg. The main type of microplastics detected in both water and sediment samples was fragment type with proportions of 57.3% and 57.9%, respectively. The most abundance particle size of microplastics was size of less than 1 mm. Colored microplastics such as black and blue were mainly found in both water samples and sediment samples. The polymer types were identified using FTIR which were polyethylene, polypropylene, polyurethane, ethylene propylene diene monomer, Butyl-Branham, and ethylene vinyl acetate.

Glass has outstanding optical properties, hardness, and durability, but its applications are limited by its inherent brittleness and poor impact resistance. Lamination and tempering can improve impact response but do not suppress brittleness. We propose a bioinspired laminated glass that duplicates the three-dimensional “brick-and-mortar” arrangement of nacre from mollusk shells, with periodic three-dimensional architectures and interlayers made of a transparent thermoplastic elastomer. This material reproduces the “tablet sliding mechanism,” which is key to the toughness of natural nacre but has been largely absent in synthetic nacres. Tablet sliding generates nonlinear deformations over large volumes and significantly improves toughness. This nacre-like glass is also two to three times more impact resistant than laminated glass and tempered glass while maintaining high strength and stiffness.

This study reports the distribution of microplastics in surface water and sediments collected from Kallar Kahar wetland, Punjab, Pakistan, which is a game reserve and hosts migratory birds during winter season. Microplastics were extracted using density separation and wet oxidation method. The microplastics identification was done under a stereo-microscope, and their polymer compositions were characterized using an attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy. The average abundance of microplastics in water and sediment samples was 88 ± 14.5 items/L and 5720 ± 2580 items/kg, respectively. The dominant shape groups of microplastics in water were fiber (58.7%), irregular fragments (32.4%), and beads (8.7%) with dominant colors as transparent > black > yellow ≈ white > red > green > pink > blue. Similar distribution in sediments was found, i.e., fiber (61.2%), irregular fragments (28.4%), and beads (10.3%) with dominant colors as transparent > pink > white > red ≈ black > blue > brown > green ≈ yellow. The ATR-FTIR spectra of visible microplastics were identified to be polypropylene (PP), high density polyethylene (HDPE), ethylene vinyl acetate (EVA), low density polyethylene (LDPE), nitrile, polymethyl methacrylate (PMMA), latex, and polyethylene terephthalate (PETE). In the study area, recreational activities, improper waste disposal, and runoff from catchment areas are the main reasons for the contamination of microplastics in the Lake. The pollution load can be minimized by taking measures such as creating awareness, promotion of ecotourism, and reducing plastic use. Graphical abstract

Microplastics (MPs) are ubiquitous in the environment, in the human food chain, and have been recently detected in blood and lung tissues. To undertake a pilot analysis of MP contamination in human vein tissue samples with respect to their presence (if any), levels, and characteristics of any particles identified. This study analysed digested human saphenous vein tissue samples (n = 5) using μFTIR spectroscopy (size limitation of 5 μm) to detect and characterise any MPs present. In total, 20 MP particles consisting of five MP polymer types were identified within 4 of the 5 vein tissue samples with an unadjusted average of 29.28 ± 34.88 MP/g of tissue (expressed as 14.99 ± 17.18 MP/g after background subtraction adjustments). Of the MPs detected in vein samples, five polymer types were identified, of irregular shape (90%), with alkyd resin (45%), poly (vinyl propionate/acetate, PVAc (20%) and nylon-ethylene-vinyl acetate, nylon-EVA, tie layer (20%) the most abundant. While the MP levels within tissue samples were not significantly different than those identified within procedural blanks (which represent airborne contamination at time of sampling), they were comprised of different plastic polymer types. The blanks comprised n = 13 MP particles of four MP polymer types with the most abundant being polytetrafluoroethylene (PTFE), then polypropylene (PP), polyethylene terephthalate (PET) and polyfumaronitrile:styrene (FNS), with a mean ± SD of 10.4 ± 9.21, p = 0.293. This study reports the highest level of contamination control and reports unadjusted values alongside different contamination adjustment techniques. This is the first evidence of MP contamination of human vascular tissues. These results support the phenomenon of transport of MPs within human tissues, specifically blood vessels, and this characterisation of types and levels can now inform realistic conditions for laboratory exposure experiments, with the aim of determining vascular health impacts.

The pollution of aquatic systems by microplastics is a well-known environmental problem. However, limited studies have been conducted in freshwater systems, especially in the Philippines. Here, we determined for the first time the amount of microplastics in the Philippines’ largest freshwater lake, the Laguna de Bay. Ten (10) sampling stations on the lake’s surface water were sampled using a plankton net. Samples were extracted and analyzed using Fourier-transform infrared spectroscopy (FTIR). A total of 100 microplastics were identified from 10 sites with a mean density of 14.29 items/m 3 . Most microplastics were fibers (57%), while blue-colored microplastics predominated in the sampling areas (53%). There were 11 microplastic polymers identified, predominantly polypropylene (PP), ethylene vinyl acetate copolymer (EVA), and polyethylene terephthalate (PET), which together account for 65% of the total microplastics in the areas. The results show that there is a higher microplastic density in areas with high relative population density, which necessitates implementing proper plastic waste management measures in the communities operating on the lake and in its vicinity to protect the lake's ecosystem services. Furthermore, future research should also focus on the environmental risks posed by these microplastics, especially on the fisheries and aquatic resources.

The amount of global plastic waste on land or in marine environments is a critical environmental issue. Plastic biodegradation by microorganisms, insect larvae, and enzymes has become one of the most popular solutions due to the ability of this strategy to generate environmentally benign byproducts, addressing ecological plastic waste concerns. This study revealed the biodegradation of ethylene vinyl acetate (EVA) by the bacterial strain identified as Klebsiella aerogenes EM011, isolated from effective microorganisms. The study found that K. aerogenes EM011 can survive in a carbon-free medium for 30 days using EVA films as the sole energy source, decomposing 0.65 ± 0.04% of 1 g of EVA film. The surface changes of the film were detected using scanning electron microscopy after treatment with K. aerogenes EM011. In addition, elemental modifications were detected in the imaged area of the plastic surfaces by energy-dispersive X-ray spectroscopy. Fourier-transform infrared spectroscopy and X-ray photoelectron spectroscopy analyses were conducted to detect changes in the functional groups and chemical components, elucidating alterations on the surface of the EVA films. Through these physicochemical analyses, the formation of carbonyl groups (C=O), ester groups (C–O), and hydroxyl groups (–OH) confirmed the oxidation of EVA. Furthermore, the oxidation led to the decomposition of the EVA film, resulting in changes in its thermal stability and molecular weight distribution. These findings show that the K. aerogenes EM011 strain plays a role in accelerating the biodegradation of EVA.

Microplastic (MP) pollution is an emerging environmental problem, due to its universal dispersion. In the present study, we determined the MP pollution in water, sediment, and fish samples of three different urban lakes of Bangladesh to assess the bioaccumulation of MPs from the lake environment to fish’s edible (flesh) and inedible tissue (gut), ecological risk and consequent human exposure to MPs by fish consumption. A total of forty-three fishes were collected from Jahangirnagar Co-Operative Housing Society (JCHS), Dhanmondi Lake (DL), and Saturia Thana Lake (MST). The average MP concentration in sediment and water of the lakes is 7588 ± 4353 MPs/kg dry weights; 142 ± 22 MPs/L, respectively. MPs were identified in the edible (2.8–20.2 MPs/g) and inedible (2.27–20.93 MPs/g) tissue of all fish species. The highest number of MPs was observed in the flesh of Labeo bata of the JCHS Lake and in the gut of Catla catla of DL. The most dominant shape of MPs was fiber and fragment, 0.1–0.4 mm was the dominant size range, and blue, purple, and transparent were the dominant colors. The presence of six polymer types was revealed by FT-IR analysis, which were polystyrene, polypropylene, nitrile, ethylene vinyl acetate, high-density polyethylene, and nylon. The concentration of MPs in fish is found to increase with the increment in body weight. The bioconcentration factor (BCF) analysis reveals that among all the fish species, Labeo bata and Oreochromis mossambicus accumulate the highest number of MPs from the lake environment. The pollution load index of MPs indicates that the sampling sites were within hazard levels III–IV. Estimated annual intake reveals that humans will be exposed to the highest number of MPs if they consume the flesh of Labeo bata of DL and JCHS Lake. Graphical Abstract

This work proposes an integrated process flowsheet for the recovery of pure crystalline Si and Ag from end of life (EoL) Si photovoltaic (PV) panels consisting of a primary thermal treatment, followed by downstream hydrometallurgical processes. The proposed flowsheet resulted from extensive experimental work and comprises the following unit operations: Shredding the PV modules to − 4 mm, after the removal and recovery of aluminum frames, junction boxes and copper cables. Delamination of the Si cells from the front soda-lime protective glass, through a thermal treatment at 550 °C for 15 min, in excess of air, in order to disintegrate the encapsulating organic material (ethylene vinyl acetate (EVA)) and the polyvinyl fluoride (PVF) polymer backsheet (Tedlar®). Separation of the detached Si flakes from the front glass and the “ash residue” and classification via mechanical screening by a perforated trommel rotary screen equipped with square wire mesh sieves. Further grinding of the recovered Si flakes by ball milling to − 90 μm, in order to increase the specific surface area, prior to the downstream hydrometallurgical process. Quantitative leaching of Ag and Al from the Si flakes in one stage by HNO 3 at ambient temperature. Alternatively, acid leaching in two stages can be applied: initially by H 2 SO 4 for Al quantitative extraction and subsequently by HNO 3 for Ag quantitative extraction at ambient temperature. In order to remove the anti-reflection coating, etching of the leached Si flakes by 2.5 M NaOH has been proven efficient and crystalline silicon of high purity was recovered. Separation and precipitation of Ag as AgCl or alternatively, Ag electrowinning from nitrate solutions and Al precipitation via solution neutralization. Graphical Abstract

Microplastics have recently emerged as a significant environmental concern due to their direct impacts on marine ecosystems. Vietnam, with its 3260-km coastline, faces an elevated risk of microplastic pollution due to various coastal anthropogenic activities. This study explored microplastic distribution in coastal surface seawater in the Southern Vietnam regions of Tien Giang, Can Gio, and Vung Tau. A total of 45 samples were collected in April, 2019, and the results showed that microplastics present at all sampling sites, with the abundance varying from 0.074 ± 0.109 pieces/m 3 in Can Gio to 0.56 ± 0.35 pieces/m 3 in Tien Giang. Estuarial sites showed higher abundances for all regions. Most microplastics were under 2.8 mm, fragmented, and primarily white or transparent. Polypropylene, polyethylene, and ethylene–vinyl acetate were the dominant polymers. This research indicates the urgency of further investigations to comprehensively understand the influence of wind patterns and other environmental factors on microplastic distribution.