Search Results (324)

Polyester fibers are extensively used in textiles, packaging, and industrial applications due to their durability and excellent mechanical properties. However, high-crystallinity polyester fibers represent a major challenge in plastic waste management due to their resistance to biodegradation. This study evaluated the biodegradation potential of environmental Bacillus isolates, obtained from mold-contaminated black bean plastic bags, toward polyethylene terephthalate (PET) and industrial-grade polyester fibers under mesophilic conditions. Among thirteen isolates, five (Bacillus altitudinis N5, Bacillus subtilis N6, and others) exhibited measurable degradation within 30 days, with mass losses up to 5–6% and corresponding rate constants of 0.04–0.05 day⁻¹. A combination of complementary characterization techniques, including mass loss analysis, scanning electron microscopy (SEM), gel permeation chromatography (GPC), and gas chromatography/mass spectrometry (GC/MS), together with Fourier-transform infrared spectroscopy (FTIR), thermogravimetric/differential scanning calorimetry (TGA/DSC), and water contact angle (WCA) analysis, was employed to evaluate the biodegradation behavior of polyester fibers. Cross-analysis of mass loss, surface morphology, molecular weight reduction, and degradation products suggests a surface erosion-dominated degradation process, accompanied by ester-bond hydrolysis and preferential degradation of amorphous regions. FTIR, TGA/DSC, and WCA analyses further reflected chemical, thermal, and surface property changes induced by biodegradation rather than directly defining the degradation mechanism. The findings highlight the capacity of mesophilic Bacillus species to partially depolymerize polyester fibers under mild environmental conditions, providing strain resources and mechanistic insight for developing low-energy bioprocesses for polyester fiber waste management. Full article

With the historical and consistent population declines of the eastern oyster (Crassostrea virginica), restoration projects commonly deploy plastic bags (polyethylene) filled with recycled oyster cultch. Oyster cultch bags are utilized as material to stabilize sediment and provide a substrate for oyster larval recruitment, which provides a habitat for associated organisms and decreases marsh erosion. In addition to the plastic mesh bags utilized to contain oyster cultch, this study also utilized three different biodegradable oyster bag material types (biopolymer, basalt, and cellulose) to determine (1) the influence of bag type on oyster population dynamics, (2) bag durability over time (<1 year), and (3) the cost–benefits for each bag type, calculated via a Weighted Product Model (WPM), within a subsection of the West Galveston Bay Estuary, Texas. For bag type, the results suggested that plastic bags were the most resilient, followed by biopolymer, basalt, and cellulose bags. Plastic bags supported the highest oyster abundance and growth, demonstrating their effectiveness for establishing breakwater reefs. The WPM analysis indicated that plastic bags are inexpensive to deploy and, due to their longevity, are easily monitored over time. However, degradation of plastic bags may introduce microplastics into the environment, posing ingestion risks for bivalves. Whereas the nature-based solutions degraded quickly, inhibiting continuous monitoring, yet the loose cultch may facilitate the natural formation of reefs over time. The results highlight tradeoffs between maximizing oyster recruitment and growth, minimizing environmental contamination, and balancing ecological performance with material sustainability in oyster reef restoration practices. Full article

The Citarum River Basin (DAS Citarum) in Indonesia faces significant challenges in waste management, necessitating a circular economy-based approach to reduce land-based pollution, which is critical for achieving the sustainability goals of the blue economy in the basin. This study addresses the complexity and inherent uncertainty in decision-making processes related to this challenge by developing a novel hybrid model, namely the Weighted Fuzzy N-Soft Set combined with the COmbinative Distance-based Assessment (CODAS) method. The model synergistically integrates the weighted 10R strategies in the circular economy, obtained via the Analytical Hierarchy Process (AHP), the capability of Fuzzy N-Soft Sets to represent uncertainty granularly, and the robust ranking mechanism of CODAS. Applied to a case study covering 16 types of waste in the Citarum River Basin, the model effectively processes expert assessments that are ambiguous regarding the 10R criteria. The results indicate that single-use plastics, particularly plastic bags (HDPE), styrofoam, transparent plastic sheets (PP), and plastic cups (PP), are the top priorities for intervention, in line with the high AHP weights for upstream strategies such as Refuse (0.2664) and Rethink (0.2361). Comparative analysis with alternative models, namely Fuzzy N-Soft Set-CODAS, Weighted Fuzzy N-Soft Set with row-column sum ranking, and Weighted Fuzzy N-Soft Set-TOPSIS, confirms the superiority of the proposed hybrid model in producing ecologically rational priorities, free from purely economic value biases. Further sensitivity analysis shows that the model remains highly robust across various weighting scenarios. This study concludes that the WFN-SS-CODAS framework provides a rigorous, data-driven, and reliable decision support tool for translating circular economy principles into actionable waste management priorities, directly supporting the restoration and sustainability goals of the blue economy in river basins. The findings suggest that targeting the high-priority waste types identified by the model addresses the dominant fraction of riverine pollution, indicating the potential for significant waste volume reduction. This research was conducted to directly contribute to achieving multiple targets under SDG 6 (Clean Water and Sanitation), SDG 12 (Responsible Consumption and Production), and SDG 14 (Life Below Water). Full article

Landfill contaminants pose significant risks to environmental and human health, particularly in rural Alaska. These communities are predominantly Alaska Native and face unique challenges in solid waste management due to geography, climate, and limited infrastructure. This scoping review assessed published research on the impacts of landfill contaminants in the Arctic (Aim 1) and Alaska specifically (Aim 2). Seventy-one studies met the inclusion criteria, all of which were used to develop a conceptual model of contaminant transport pathways. Thirty-nine studies included Alaska-specific research: thirty-three focused on environmental impacts, and six addressed human health (e.g., birth outcomes, cancer). Key topics included waste burning, heat generation, carbon release, leachate characterization, and water or sediment contamination. Evidence specific to Alaska suggested landfill leachate may contaminate surface water and groundwater, and that microbes can migrate beyond the landfill site boundaries in communities using honeybuckets (plastic bag-lined buckets that collect human waste). Landfill contaminants also impacted wildlife through consumption of garbage, which may have human health implications for subsistence-based communities. Major research gaps remain in understanding individual-level exposures, the effects of emerging contaminants, and the mechanisms of contaminant transport pathways. Further research designed for causal inference is needed to support improvements to public and environmental health. Full article

This study aimed to evaluate the shelf life of intermediate moisture longan (IML). A hurdle technology approach was applied, combining osmotic dehydration (OD), hot-air drying, and packaging methods: aluminum foil-laminated plastic bags with nitrogen flushing (Al bag with nitrogen), aluminum foil-laminated plastic bags without nitrogen (the Al bag without nitrogen), and clear plastic bags. Samples were stored at 4, 25, 35, and 45 °C for 24 weeks (six months). The combination of these preservation techniques was effective in extending the shelf life of IML products. Quality changes in IML during storage were significantly influenced by packaging type, storage temperature, and storage duration (p ≤ 0.05). Products stored in all three types of packaging at low temperatures retained better color (L* 31.92 ± 0.97–32.67 ± 1.47) and higher sensory scores (6.5 ± 1.4–6.6 ± 1.5) compared to those stored at higher temperatures (L* 19.54 ± 1.00–20.90 ± 1.48, 3.3 ± 1.6–4.1 ± 1.7). Accelerated shelf life testing using the Arrhenius equation was applied to predict changes in color and sensory acceptance. The kinetics of these quality changes followed the first-order reaction models. Among the packaging types, IML stored in Al bags with nitrogen exhibited the lowest rate constants, indicating slower quality deterioration and better protection compared to Al bags without nitrogen and clear plastic bags. The predictive model demonstrated strong agreement with the experimental data, accurately predicting shelf life at 25 °C and above. However, the model projected a potential shelf life of up to 58 weeks for IML samples packaged in aluminum bags with nitrogen and stored at 4 °C; this projection extended beyond the 24-week experimental period, which still verified a minimum shelf life of 24 weeks. This technology reduces post-harvest food loss, advances packaging innovation for agro-industry, and strengthens food security. Full article

The enormous applications of various nanoparticles (NPs) have raised the possibility that humans may be simultaneously exposed to mixtures of them in real life. Realistically, this situation may apply to plastic NPs, mainly derived from the breakdown of larger plastics, and to silver NPs, both of which are among the most frequently detected NPs in the envirnment due to their applications in healthcare, consumer products, and water purification. Although numerous studies have examined the toxicity of plastic and silver NPs individually, knowledge of their combined toxicity remains limited. Hence, the main objective of our study was to investigate the toxicity of high-density polyethene nanoparticles (HDPE NPs), thermally isolated from food-cooking bags, in combination with citrate-stabilised silver nanoparticles (AgNPcit) to Caco-2 and HT29MTX cells growing in 2D monoculture or in 3D triple-culture with Raji cells. Cellular uptake of NPs was quantified from the side-scatter (SSC) signal in flow cytometry; toxicity was evaluated by the neutral red assay; apoptosis was evaluated by the Annexin V method; and induction of oxidative stress was evaluated by a fluorescent method using DCFDA and DHR probes. Both cell lines took up both types of NPs; however, HT29MTX cells were more effective in the NPs’ uptake. Interestingly, HDPE NPs and AgNPcit mutually inhibited each other’s uptake, which suggests a similar mechanism of entry. Both types of NPs were toxic to both cell lines growing in monoculture; Caco-2 cells were more susceptible than HT29MTX. The toxicity was attributed to the induction of oxidative stress and associated apoptosis. In line with the mutual inhibition of the NPs’ uptake, the toxic effect of both NPs in the mixture was less than that expected as the sum of individual treatments. The toxic effects of both NPs or their mixture were less pronounced in the triple-culture Caco-2/HT29MTX/Raji, than in Caco-2 and HT29MTX growing in monoculture. Full article

C footprint is a feature used to search the integral life cycle of a product to predict its environmental impact. The packaging industry is changing rapidly to the production of biodegradable products to mitigate the negative environmental consequences of the use of single-use packages. It is thought that biodegradable packages should be more sustainable than traditional plastics due to the sources of the raw materials used to produce them, but this is not always true and depends on the issues considered, the methodology, and the scale analyzed. Limited research includes case studies from developing countries where waste management is less efficient and where the environmental impacts of single-use packaging can be more significant. This paper evaluates the C footprint of bags and dishes made from traditional or local biodegradable sources in an Amazonian settlement of Colombia, such as thermoplastic cassava starch and powdered plantain leaves, to evaluate the impact of locally made biodegradable packaging vs. imported petrochemical ones. Results show that using local raw materials and in situ production reduces the C footprint of biodegradable packages, considering that the energy source for production and transport are important contributors to the C footprint beyond the raw materials used, with ratios that can be between 0.1 and 7 times more kg CO₂ eq generated per functional unit. Full article

Reliable estimates of soil stiffness and energy dissipation are essential for dynamic-response design. This study benchmarks machine learning models for predicting shear modulus (G) and damping ratio (D) using 2738 resonant-column measurements. After data quality control and F-test feature screening, five model families—decision trees and ensembles, support-vector machines, Gaussian-process regression, neural networks, and linear baselines—were trained under uniform 10-fold cross-validation and evaluated with R², RMSE, MAE, and MSE, while recording training time to reflect practical constraints. Results show that model choice materially affects performance. For G, a bagged ensemble of trees delivered the best accuracy (R² = 0.9827) with short training times; single trees provided transparent, fast screening models. For D, tree-based ensembles again performed strongly (R² up to 0.8565), while a rational-quadratic Gaussian-process model offered competitive accuracy (R² ≈ 0.81) together with prediction intervals that support risk-aware design. Feature influence aligned with soil mechanics: G was most sensitive to effective confining pressure (σ′0), initial void ratio (e0), and density (ρ); D was governed mainly by overconsolidation ratio (OCR), depth (z), σ′0, and plasticity, with notable interactions among stress, strain amplitude (γ), and moisture state. The findings provide practice-oriented guidance: use bagged trees for routine predictions of G and D, and add Gaussian-process regression when uncertainty quantification is required. The approach complements laboratory testing and supports safer, more economical dynamic-response design. Full article

This research examined the mechanical, physical, thermal, and durability properties of plastic-based composites made from MSW, namely ultra-high-temperature (UHT) cartons, plastic bags, aluminum foil, and foil bags under both unweathered and accelerated weathering conditions to evaluate their potential as paving slab materials. Composite samples with varying mixing ratios were fabricated and tested based on an experimental design. Statistical analyses using one-way ANOVA confirmed the significant effects of composition on material performance (p < 0.05). The results demonstrated that the mixing ratio markedly influenced mechanical properties. The composite containing 50 wt% UHT carton and 50 wt% foil bags (U50F50) achieved the highest modulus of rupture (121.20 MPa) and modulus of elasticity (2.98 GPa), as well as compressive strength (28.56 MPa), compressive modulus (2.12 GPa), screw withdrawal resistance (54.25 MPa), and hardness (66.25). Under accelerated weathering, all of the composites showed moderate reductions in strength (10 to 30%) due to plastic degradation and surface cracking. In contrast, the composites containing high paperboard fractions (U80P15A5) exhibited greater WA (3.55%) and TS (3.04%), attributed to the hydrophilic nature of cellulose. The inclusion of foil bags effectively reduced WA and TS by limiting moisture penetration. Density measurements demonstrated a gradual increase (0.99 to 1.05 g/cm³) with higher foil content, while accelerated weathering induced an average 10% density reduction. Abrasion resistance improved in foil-rich composites, with U50F50 showing the lowest weight loss (8.56 to 14.02%), confirming its superior structural integrity under mechanical wear. Thermal analysis indicated low conductivity values (0.136 to 0.189 W/m·K), demonstrating favorable insulation performance compared to conventional paving materials. However, higher foil bag fractions enhanced heat conduction, balancing mechanical strength with thermal functionality. Overall, MSW-derived composites containing 30 to 50 wt% foil bags exhibited optimal mechanical durability, abrasion resistance, and thermal stability, making them promising candidates for sustainable paving slab production with low environmental impact and enhanced service life. Full article

The overconsumption of plastic packaging has alarming repercussions on the environment, notably through waste accumulation in public spaces and clogged drains. This study identifies factors driving plastic proliferation, analyzes their impacts, and proposes strategies for sustainable waste management. A cross-sectional design combined document review, field observations, and interviews with 156 households and 24 informants. Descriptive statistics characterized consumption patterns and service access. Impacts were assessed through litter hotspots, blocked drains, flood-prone points, and reported health risks. Households used five to six plastic bags daily, while collection coverage remained below 50%, sustaining persistent leakage. Findings reveal excessive reliance on plastics, shaped by technical, social, and institutional gaps, including weak segregation and limited pre-collection. Agoè-Nyivé 4, a fast-growing peri-urban commune within Greater Lomé, faces limited services but high consumption, making it a relevant case for rapidly growing municipalities. Yet the population often adopts counterproductive practices, hampering responsible waste management. A policy mix is outlined: expanding pre-collection and door-to-door services, integrating informal collectors, and targeted community sensitization. Without urgent interventions, plastic leakage will intensify environmental degradation, flooding, and health risks. The study recommends integrated policy measures to curb single-use dependence and foster a local circular economy. Full article

The lignin nanoparticle (LNP) was prepared by the self-assembly method and further blended with poly(butylene adipate-co-terephthalate) (PBAT) to obtain a PBAT/LNP composite using a solvent casting method. It was found that the nano-modification of lignin effectively improved the compatibility between the components, and the mechanical properties, gas barrier properties, UV resistance, degradation, and antibacterial properties of the PBAT/LNP composite. Compared with PBAT, the tensile strength, elongation at break, and elastic modulus of the PBAT/LNP composite with 8 wt% LNP (PBAT/LNP-8) increased by 37.36%, 47.30% and 50.70%, respectively. Moreover, the mechanical properties, UV-blocking performance, and gas barrier properties of PBAT/LNP-8 were better than those of the commercial degradable packing bag, and the composite derived from PBAT and lignin extracted from wheat straw also showed excellent properties. This work explored a way to expand the utilization of lignin from lignocellulosic biomass, which not only helped to solve the environmental pollution caused by the widespread use of non-degradable plastics, but also promoted the replacement of fossil resources. Full article

The environmental impact of companion animals has received little scientific attention compared to that of livestock, even though the global dog population is rapidly increasing, particularly in urban areas. This review addresses the overlooked contribution of dogs to environmental emissions, focusing on feces, urine, packaging waste, and other care-related by-products. The current knowledge from livestock research provides useful analogies for understanding nutrient excretion and gaseous emissions from dog feces, and data on nitrogen and phosphorus inputs highlight their potential to pollute soil and water. We also examine the role of plastic waste from food packaging, waste bags, and accessories, which can degrade into microplastics, and discuss recent developments in biodegradable materials. Evidence shows that owner choices—such as diet composition, protein sources, and product selection—directly affect the environmental pawprint of dogs. Mitigation strategies include optimizing diets to reduce nutrient excretion, applying feed additives developed for livestock, and improving waste management through composting or the use of emission-reducing amendments. In conclusion, dogs should no longer be viewed merely as individual household companions but as a population with a measurable environmental pawprint. Including dogs in emission reporting systems would provide a more accurate basis for mitigation policies and sustainable urban planning. Full article

Bioplastics are plastics derived from natural resources like corn starch, biomass, sugarcane bagasse, and food waste. Unlike fossil-fuel-based plastics, they are entirely or partially bio-degradable. Cellulose- and starch-based bioplastics are already used for applications like packaging, cutlery, bowls, straws, and shopping bags. With the aim of developing eco-friendly biofilms for various applications, cellulose nanocrystals (CNCs) were obtained by sulfuric acid hydrolysis of waste cellulose and functionalized by transesterification with exhausted oils. The resulting transesterified nanocellulose (TCNC) was used as a reinforced material of PLA at different concentrations to develop biofilms using the solvent casting method. The biofilms composed of PLA and TCNC were assessed through Fourier-transform infrared spectroscopy (FTIR), mechanical properties, moisture barrier property (water vapor permeability rate—WVTR), and measurements of the water contact angle (WCA). A scanning electron microscopy (SEM) analysis confirmed the high compatibility of the PLA blended with TCNC at 1% and 3%. The inclusion of transesterified cellulose nanocrystals (TCNCs) to PLA increased the hydrophobicity, the film tensile strength, and the water vapor barrier properties of the final composite films. Full article

Thailand generated 27.2 million tons of municipal solid waste in 2024, of which 12% was plastic waste, predominantly single-use plastics. The mismanagement of plastic waste can lead to significant long-term environmental issues, including the release of toxic chemicals through open burning and air pollution, posing risks to human health. Effective and efficient plastic waste collection and recycling are therefore essential to address the reduction and management of plastic waste, as well as to support a low-carbon energy transition. This study assessed three community-driven initiatives by conducting a comparative sustainability assessment of plastic bag recycling under real-life conditions in Thailand using a multi-criteria decision-making framework. The results of the assessment in three municipalities showed that the actual collection rates in all initiatives remained extremely low (0.0014–0.1555%). The highest rankings were observed with recycling initiatives driven by superior collection rates and favorable economic returns. The hindrances to promoting sustainability are found to be due to policy inconsistency, ineffective leadership, and behavioral barriers. The practical collection rates should increase to at least 25% to be more sustainable in terms of economic, social, and environmental aspects compared to those without the recycling initiative. These findings, thus, provide specific targets for improving plastic waste separation and management strategies in all regions facing similar challenges. Full article

The basis for the assessment of the quality of selective waste collection, as well as the direction of modernization of municipal waste sorting technology, should be morphological composition studies. According to research, the gold standard for the assessment of the quality of selective waste collection, as well as the direction of modernization of municipal waste sorting technology, is morphological composition studies. Selective collection of municipal waste is an indispensable element of the waste management system, particularly important in terms of the increasing recycling levels obtained. The recycling of problematic and polluting plastics is one of the main challenges of the European circular economy. By problematic plastics, we mean those that are not suitable for recycling, or their recycling is difficult and expensive for technological reasons, resulting in problems with their management on the market. In 2022, the level of plastic recycling in Europe reached 26.9%. This article presents the results of studies on the morphological composition of selectively collected plastics and metals carried out in the summer and autumn of 2023 for a large city in Poland in the Silesian agglomeration. As a result, the quality of selectively collected waste, the share of pollutants in it, depending on the type of development, and the real possibilities of its recovery were determined. As part of the results obtained, a simulation was also carried out on how the deposit system planned from the first of October 2025 in Poland will affect the morphological composition of plastics and metals currently collected in the yellow container/bag. Full article