Search Results (93)

Biodegradable plastics are not a primary solution to plastic pollution, and empirical evidence on whether they are environmentally friendly remains lacking. In this study, we systematically compared the toxic effects of traditional microplastics (polypropylene, PP; polystyrene, PS) with biodegradable microplastics (polylactic acid, PLA; polyhydroxyalkanoates, PHA) on the haplic phaeozem ecosystem. Through mathematical modeling analysis, it was found that earthworms initially rely on antioxidant enzymes to resist stress, mid-term activation of detoxifying enzymes to repair damage, and maintaining physiological balance through metabolic regulation and immune enhancement in later stages. We elucidated their mechanism differences: PLA and PP caused severe damage to the antioxidant system and cell membrane, with PLA mainly relying on POD to clear peroxides and PP relying on GST. In addition, PLA and PS can induce early neurotoxicity (AChE), while PHA induces late neurotoxicity. Furthermore, this study provides direct evidence proving that biodegradable microplastics are not environmentally friendly by breaking through the one-way research framework of “microplastic biotoxicity” and innovatively constructing a path analysis model that links biological physiological responses with soil ecological functions. We also provide a scientific basis to evaluate the ecological risks of microplastic pollution in soil and the whether biodegradable plastics are truly environmentally friendly. Full article

The paper industry is always looking for possible solutions for new fiber-based products, such as protective and cushioning materials. These materials must be carefully designed to provide effective cushioning while also being lightweight to reduce transportation costs. Additionally, they need to offer protection from environmental and mechanical damage, besides having good processability to ensure proper buffering. The widely used protective and cushioning materials, such as plastic foams and expanded or extruded polystyrene, create significant disposal challenges. Therefore, there is increasing demand for biodegradable and sustainable materials for cushioning applications. The focus of our research was to develop fiber-based foams and investigate the influence of different compositions (hardwood and softwood) of cellulose fibers on the basic (mass, thickness, density) and mechanical properties (three-point bend test, tensile properties). Foams made entirely from short eucalyptus fibers (100S) exhibited the highest density (28.0 ± 0.34 kg/m³) and lowest thickness (38.82 ± 4.21 mm), resulting in superior tensile strength and elastic modulus but lower strain at break. In contrast, foams composed of long spruce fibers (100L) had the lowest density (19.0 ± 0.27 kg/m³) and highest thickness (58.52 ± 1.50 mm), with lower strength and stiffness but much higher ductility and porosity (confirmed by ~30% higher air permeability compared to 100S). Blended formulations demonstrated intermediate behavior, with the 50S50L foam showing a favorable balance of strength, stiffness, and flexibility. Visual analysis confirmed heterogeneous fiber distribution with localized agglomerates and compaction at the bottom layer due to casting. To further interpret the complex relationships within the dataset and uncover patterns, Principal Component Analysis (PCA) was applied to all experimental results. The findings of the research contribute to the broader understanding of how different fiber types and blends impact the performance of sustainable cellulose-based foams, with potential implications for the development of biodegradable packaging and lightweight construction materials. Full article

The growing demand for sustainable and energy-efficient construction has driven significant interest in the development of advanced insulation materials that reduce energy usage while minimizing environmental impact. Although conventional insulation materials such as polyurethane, polystyrene, and mineral wools offer excellent thermal and acoustic performance, they are derived from non-renewable sources, have high embodied carbon (EC) (up to 7.3 kg CO₂-eq/kg), and pose end-of-life disposal challenges. Thus, this review critically examines the emergence of insulation materials derived from natural and recycled sources, which align with circular economy principles by minimizing waste, promoting material reuse, and extending product life cycles. Sustainable alternatives such as sheep wool, hemp, flax, and jute not only exhibit competitive thermal conductivity (as low as 0.031–0.046 W/m·K) and very good sound absorption but also offer low EC, biodegradability, and regional availability. Despite some limitations, including variable fire resistance and thickness requirements, these bio-based insulators present a viable path toward greener building solutions. The review highlights that waste-based insulation materials are essential for sustainable construction due to their low EC, renewability, and contribution to waste reduction, making them a necessary alternative even when conventional materials demonstrate superior short-term performance. Full article

Microplastics (MPs) and nanoplastics (NPs) can affect microbial abundance and activity, likely by damaging cell membrane components. While their effects on anaerobic digestion are known, less is understood about their impact on microbes involved in contaminant bioremediation. Chlorinated volatile organic contaminants (CVOCs) such as tetrachloroethene (PCE) and explosives like hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) are common in the environment, and their bioremediation is a promising cleanup strategy. This study examined how polystyrene (PS) and polyamide 6 (PA6) MPs and NPs influence CVOC and RDX biodegradation. PS particles did not inhibit the CVOC-degrading community SDC-9, but PA6 MPs impaired the reductive dechlorination of trichloroethene (TCE) to cis-1,2-dichloroethene (cis-DCE), causing a “cis-DCE stall” with no further conversion to vinyl chloride (VC) or ethene. Only 45% of TCE was dechlorinated to cis-DCE, and Dehalococcoides mccartyi abundance dropped 1000-fold in 35 days with PA6 MPs. In contrast, neither PA6 nor PS MPs and NPs affected RDX biotransformation. These results highlight the significant impact of PA6 MPs on CVOC biodegradation and the need to consider plastic pollution in environmental management. Full article

Soil microplastic pollution poses a significant threat to the integrity of terrestrial ecosystems and agricultural sustainability. This review provides a comprehensive synthesis of recent progress on soil microplastic (MP) sources, ecological impacts, and separation technologies. Agricultural practices (e.g., residual plastic mulch and wastewater irrigation) and atmospheric deposition serve as primary drivers of contamination accumulation, with pronounced spatial heterogeneity observed across regions. Predominant MP types such as polyethylene, polystyrene, and polypropylene disrupt soil structure and biogeochemical processes through three core mechanisms: physical interference, chemical toxicity, and biological accumulation. These particles further form carrier–pollutant complexes, exacerbating ecotoxicological impacts across trophic levels. While emerging separation techniques like magnetic separation and solvent extraction demonstrate enhanced efficiency, their implementation faces challenges stemming from soil matrix complexity and high operational costs. This article underscores the need for global collaborative efforts to accelerate innovation in biodegradable polymers, offering practical pathways for sustainable soil management. Full article

Plastic is a major organic pollutant globally but has only recently been recognized for its recalcitrant nature and resistance to degradation. Although vast amounts of plastic debris are overwhelming the planet, the search for solutions to its degradation has only recently begun. One of the most well-known agents of plastic biodegradation is the larvae of Tenebrio molitor, which can alter the structure of polymers like polystyrene. However, while this insect can cause deterioration, its frass, which still consists of polystyrene microplastics, remains a problem. We investigated whether this frass could be further degraded by strains of white rot fungi, specifically Pleurotus eryngii and Trametes versicolor. We introduced two PS derivatives (styrofoam and stirodure) to the fungi in liquid media and evaluated oxidative metabolism enzymes (laccase, Mn-peroxidase, lignin-peroxidase) activities, and the phenolic products of the potential aromatic polymer degradation in the media. Finally, we evaluated FTIR spectra to determine if we could detect changes in polystyrene molecule degradation. Both fungi produced high amounts of enzymes, particularly when the polystyrene was present. Large quantities of phenolic substances were simultaneously detected, some associated with polystyrene degradation. FTIR spectra of different polystyrene products confirmed species-specific mechanisms for their degradation by experimental fungal strains. Full article

Biochemical monomer upcycling of plastic waste and its conversion into value-added products is deemed necessary, as it provides a greener and more sustainable solution to plastic waste management. In the current study, the polystyrene (PS) biodegradation potential of the fungus Phanerochaete chrysosporium NA3 was evaluated using various analytical techniques, such as Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), gel permeation chromatography (GPC), and high-performance liquid chromatography (HPLC). The biodegradation capacity of the fungal strain was further evaluated using a carbon dioxide (CO₂) evolution test, which showed that the PS films treated with NA3 produced more CO₂, indicating the strain’s ability to successfully utilize PS as a carbon source. The FTIR analysis of the PS films treated with NA3 showed modifications in the polymer chemical structure, including the formation of carbonyl and hydroxyl groups, which suggests the enzymatic dissociation of the polymer and the associated biodegradation mechanism. Pretreatments were found to be effective in modifying the polymer’s properties, making it more susceptible to microbial degradation, thus further accelerating the biodegradation process. The current study strongly advocates that P. chrysosporium (NA3) can be effectively used for the biochemical monomer recovery of PS waste and could be further utilized in the upcycling of plastic waste for its conversion into value-added products under the concept of circular economy. Full article

The aim of this study is to investigate the potential of wood composites as sustainable acoustic materials and to explore their integration with advanced manufacturing techniques for improved performance. Using a comprehensive review methodology, the paper analyzes recent innovations in wood composites, focusing on the combination with other sustainable materials such as expanded polystyrene (EPS) and natural fibers. The results show that wood composites can achieve sound absorption coefficients (α) of up to 0.9, with oak panels showing transmission losses of up to 11 dB. In addition, advanced designs, including biodegradable panels and lightweight honeycomb structures, significantly improve sound transmission loss, with an average sound transmission loss (TLeq) of up to 28.3 dB reported for composite panels made from waste tire rubber. In addition, the study highlights the environmental benefits achieved through the use of agricultural byproducts and industrial waste in the development of these materials, confirming the role of wood composites as a carbon-neutral alternative in the quest for green building solutions. This study provides valuable insights into the transformative potential of wood composites for sustainable acoustic applications. Full article

Biodegradation is an advanced method for reducing plastic waste in the environment, involving the participation of microbial communities with plastic-degrading properties. Our study presents a novel halophilic community isolated from the plastic-contaminated region in Burgas Lake, Bulgaria. In a medium containing 15% sodium chloride, the community can degrade a significant amount of polycaprolactone (PCL) as a sole carbon source, as well as the plastics polystyrene (PS) and polypropylene (PP), albeit to a lesser extent. The community showed high hydrophobicity and the ability to form a biofilm on PCL beads, as well as high esterase activity and significant biodegradation capacity, as demonstrated by measuring the weight of the PCL material after cultivation for 4 and 8 weeks. Moreover, a scanning electron microscopy (SEM) analysis revealed visible cracks, craters, and holes in the surface of the polymer particles. The metagenomic study revealed that Halomonas profundus dominated the community with a proportion of 95.13%, followed by Alloalcanivorax venustensis (2.73%), Chromohalobacter marismortui (0.72%), and Halomonas caseinilytica (0.78%). However, most of the species in the community were not previously known as PCL-degrading. Thus, studying the diversity of the halophile community can significantly improve our fundamental understanding and clarify their potential applications for environmental and water–plastic remediation. Full article

The degradation of polystyrene (PS) represents a significant challenge in plastic waste management due to its chemical stability and low biodegradability. In this study, the catalytic degradation mechanisms of PS were investigated by density functional theory (DFT)-based calculations using the hybrid functional B3LYP and the 6-311G++(d,p) basis in Gaussian 16. The influence of acidic (AlCl₃, Fe₂(SO₄)₃) and basic (CaO) catalysts was evaluated in terms of activation energy, reaction mechanisms, and degradation products. The results revealed that acid catalysts induce PS fragmentation through the formation of carbocationic intermediates, promoting the selective cleavage of C-C bonds in branched chains with bond dissociation energies (BDE) of 176.8 kJ/mol (C1-C7) and 175.2 kJ/mol (C3-C8). In contrast, basic catalysts favor β-scission by stabilizing carbanions, reducing the BDE to 151.6 kJ/mol (C2-C3) and 143.9 kJ/mol (C3-C4), which facilitates the formation of aromatic products such as styrene and benzene. Fe₂(SO₄)₃ was found to significantly decrease the activation barriers to 328.12 kJ/mol, while the basic catalysts reduce the energy barriers to 136.9 kJ/mol. Gibbs free energy (ΔG) calculations confirmed the most favorable routes, providing key information for the design of optimized catalysts in PS valorization. This study highlights the usefulness of computational modeling in the optimization of plastic recycling strategies, contributing to the development of more efficient and sustainable methods. Full article

Nanoarchitectonics influences the properties of objects at micro- and even macro-scales, aiming to develop better structures for protection of product. Although its applications were analyzed in different areas, nanoarchitectonics of food packaging—the focus of this review—has not been discussed, to the best of our knowledge. The (A) structural and (B) functional hierarchy of food packaging is discussed here for the enhancement of protection, extending shelf-life, and preserving the nutritional quality of diverse products including meat, fish, dairy, fruits, vegetables, gelled items, and beverages. Interestingly, the structure and design of packaging for these diverse products often possess similar principles and methods including active packaging, gas permeation control, sensor incorporation, UV/pulsed light processing, and thermal/plasma treatment. Here, nanoarchitechtonics serves as the unifying component, enabling protection against oxidation, light, microbial contamination, temperature, and mechanical actions. Finally, materials are an essential consideration in food packaging, particularly beyond commonly used polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET), polystyrene (PS), and polyvinyl chloride (PVC) plastics, with emphasis on biodegradable (polybutylene succinate (PBS), polyvinyl alcohol (PVA), polycaprolactone (PCL), and polybutylene adipate co-terephthalate (PBAT)) as well as green even edible (bio)-materials: polysaccharides (starch, cellulose, pectin, gum, zein, alginate, agar, galactan, ulvan, galactomannan, laccase, chitin, chitosan, hyaluronic acid, etc.). Nanoarchitechnotics design of these materials eventually determines the level of food protection as well as the sustainability of the processes. Marketing, safety, sustainability, and ethics are also discussed in the context of industrial viability and consumer satisfaction. Full article

Microplastics (MPs), defined as plastic particles smaller than 5 mm, have emerged as a global environmental and public health crisis, infiltrating air, water, soil, and food systems worldwide. MPs originate from the breakdown of larger plastic debris, single-use plastics, and industrial processes, entering food. Emerging evidence underscores the ability of MPs to cross biological barriers, including the blood–brain barrier, triggering neuroinflammatory responses and contributing to neurodegenerative diseases such as Alzheimer’s and Parkinson’s. Polystyrene (PS), a common type of MP, activates microglial cells, releasing pro-inflammatory cytokines like tumor necrosis factor (TNF-α) and interleukins, which increase neuronal damage. MPs have also been linked to cardiovascular diseases, with studies detecting polyethylene (PE) and polyvinyl chloride (PVC) in carotid artery plaques, increasing the risk of myocardial infarction and stroke. Furthermore, MPs disrupt endocrine function, alter lipid metabolism, and induce gut microbiome imbalances, posing multifaceted health risks. In the MENA region, MP pollution is particularly severe, with the Mediterranean Sea receiving an estimated 570,000 tons of plastic annually, equivalent to 33,800 plastic bottles per minute. Studies in Egypt, Lebanon, and Tunisia document high MP concentrations in marine ecosystems, with herbivorous fish like Siganus rivulatus containing over 1000 MPs per individual due to the ingestion of contaminated seaweed. Despite these findings, public awareness and regulatory frameworks remain inadequate, with only 24% of Egyptians demonstrating sufficient knowledge of safe plastic use. This review emphasizes the urgent need for region-specific research, policy interventions, and public awareness campaigns to address MP pollution. Recommendations include sustainable waste management practices, the promotion of biodegradable alternatives, and enhanced monitoring systems to mitigate the health and environmental impacts of MPs in the MENA region. Full article

Plastics pose a significant threat to marine ecosystems, owing to their slow biodegradability. Microplastics (MPs), in particular, affect marine life and maricultural organisms and can enter the food chain via ingestion by marine organisms, leading to bioaccumulation in predators, including humans. This study assessed the toxic interactions between polystyrene microplastic particles (PSMPs) and cadmium (Cd) and phenanthrene (Phe) using marine bivalves. While PSMPs were non-toxic to Pacific oysters (Crassostrea gigas), the toxicity of Cd and Phe was concentration-dependent. In most conditions, PSMPs reduced the toxicity of Cd and Phe, but in simultaneous exposure, they acted as Cd messengers, altering the toxicity during the adult stage. This study confirms that PSMPs can interact with coastal environmental pollutants, thereby accelerating biotoxicity and posing a significant threat to marine wildlife, mariculture, and human health. It also highlights the need to assess MP toxicity in coastal environments and their interactions with pollutants. Full article

Natural fiber-reinforced composites are composite materials composed of natural fibers, such as plant fibers and synthetic biopolymers. These environmentally friendly composites are biodegradable, renewable, cheap, lightweight, and low-density, attracting attention as eco-friendly alternatives to synthetic fiber-reinforced composites. In this study, natural fiber-reinforced polymer foam core layered composites were produced for the automotive industry. Fabrics woven from goat wool were used as the natural fiber. Polymer foam with expanded polystyrene (EPS) and extruded polystyrene (XPS) structures was used as the core material. During production, fibers were bonded to the upper and lower layers of the core structures using resin. The hand lay-up method was used in production. After resin application, the samples were cured under a heated press for 2 h. After the production was completed, the material was cut according to the standards (10-20-30 Joule), and impact and bending tests were conducted at three different energy levels. The experiments revealed that at 10 J, the material exhibited rebound; at 20 J, it showed resistance to stabbing; and at 30 J, it experienced penetration. While EPS foam demonstrated higher impact resistance in the 10 J test, it was found that XPS foam exhibited better impact resistance and absorption capabilities in the 20 J and 30 J tests. Due to the open and semi-closed cell structure of EPS foams and the closed cell structure of XPS foams, it has been concluded that XPS foams exhibit higher impact resistance and better energy absorption properties Full article

Mechanically driven cellular preference for drug carriers can enhance selectivity in cancer therapy, underscoring the importance of understanding the physical aspects of particle uptake. In this study, it was hypothesized that elongated particles might be preferentially taken up by deformable, aggressive cancer cells compared to normal cells. Two film-stretching methods were tested for 0.8–2.4 μm polystyrene (PS) particles: one based on solubility in organic solvents and the other on heat-induced softening. The heat-induced method produced more homogenous particle batches, with a standard deviation in the particle aspect ratio of 0.42 compared to 0.91 in the solvent-based method. The ability of cells to engulf elongated PS particles versus spherical particles was assessed in two subsets of human melanoma A375 cells. In the more aggressive cancer cell subset (A375+), uptake of elongated PS particles increased by 10% compared to spherical particles. In contrast, the less aggressive subset (A375−) showed a 25% decrease in uptake of elongated particles. This resulted in an uptake ratio between A375+ and A375− that was 1.5 times higher for elongated PS particles than for spherical ones. To further demonstrate relevance to drug delivery, elongated paclitaxel-loaded biodegradable, slow-releasing poly(lactic-co-glycolic) acid (PLGA) particles were synthesized. No significant difference in cytotoxic effect was observed between A375+ and A375− cells treated with spherical drug-loaded particles. However, treatment with ellipsoidal particles led to a significantly enhanced cytotoxic effect in aggressive cells compared to less aggressive cells. These findings present promising directions for tailored cancer drug delivery and demonstrate the importance of particle physical properties in cellular uptake and drug delivery mechanisms. Full article