Search Results (141)

Plastic pollution is a problem for many municipalities, water authorities, and industries, including transportation, energy, agriculture, fisheries, real estate, tourism, hospitality, insurance, and healthcare. Efforts to understand and mitigate plastic pollution would benefit from a dedicated map satisfying basic criteria including traceability, scalability, spatio-temporal resolution, and data flexibility. This article details and demonstrates how several existing pollution maps satisfy these criteria and makes recommendations on their use for specific activities, including temporal monitoring, root-cause analysis (RCA), cleanups, and tourism guides. Advantages of using plastic density rather than piecewise logs as the primary data format are highlighted, in particular feasible memory requirements and access to cloud data. Environmental plastic mapping by passive optical sensors, which offer the potential of comprehensive qualified data, is also surveyed, including demonstration of an original shortwave infrared (SWIR) polarization imager, and dynamic plastic pollution monitoring is demonstrated through the application-programming interface (API) of the Google Maps platform utilizing both sensor and published survey data. Full article

Mass–balance discrepancies exist between estimated land-based inputs and observed marine plastic inventories. While current global mass–balance models predominantly treat the open ocean as a passive terminal sink, they overlook the rapid expansion of offshore and deep-sea industrial frontiers. This review identifies offshore and deep-sea activities as active, in situ emission nodes of microplastics (MPs). Through a bibliometric analysis and numerical descriptions of studies, we document that direct offshore emissions are underrepresented in the current literature. By synthesizing these limited quantitative data, preliminary metrics indicate localized MP enrichment signals and elevated biological exposure near specific offshore infrastructures. Furthermore, plastics released directly into the marine environment bypass terrestrial weathering, undergoing distinct multiscale aging pathways governed by the complex interplay of wave-induced physical fragmentation bounded by critical size thresholds, UV-driven chemical photo-oxidation, and biological interactions. We conclude that refining global plastic budgets supports moving toward an integrated ocean-industrial framework. However, the synthesis remains constrained by data scarcity and high methodological heterogeneity across different environmental matrices. Future strategies must prioritize standardized in situ flux quantification and the incorporation of MP emission risks into offshore Environmental Impact Assessments. Full article

Expanded polystyrene litter in marine environments harbors diverse and distinct microbial communities, referred to as the plastisphere. This study aimed to investigate the monthly dynamics of bacterial and potentially pathogenic bacterial (PPB) communities on expanded polystyrene over one year. Vibrio species dominated the PPB community, cooccurring at consistently higher abundances on expanded polystyrene than in the surrounding seawater, particularly under higher temperatures and low dissolved organic carbon (DOC) levels. At a temperature threshold of 16 °C, the abundance of zoonotic species, such as Vibrio parahaemolyticus and Vibrio alginolyticus, increased significantly. Some psychrotrophic Vibrio spp. were detected under moderately eutrophic conditions, suggesting that expanded polystyrene may also serve as a dispersal vector facilitating their transport to more favorable habitats. Multivariate analyses, including partial least squares path modeling, revealed temperature and DOC as the primary environmental factors influencing PPB community composition. However, environmental responses varied by taxonomic groups, with different preferences observed under varying eutrophic conditions. In conclusion, these findings demonstrate that expanded polystyrene litter supports a selective and environmentally responsive bacterial population, highlighting the potential role of plastic debris in promoting pathogenic bacterial persistence and spread in marine ecosystems, particularly under conditions associated with climate change, including warming and eutrophication. Full article

Plastic waste is estimated to represent 40–80% of the total amount of marine litter, with polyethylene (PE) and polypropylene (PP) being the most abundant polymeric components. The recovery and recycling of marine plastic debris are therefore essential to mitigate environmental pollution and limit the generation of secondary microplastics. In this work, a mechanical recycling strategy was investigated for the valorization of a polyethylene-rich plastic fraction (PE-rf) recovered from the marine environment, characterized by high heterogeneity and persistent inorganic contamination. Different pre-treatment routes, including cryogenic grinding and planetary ball milling, as well as blending approaches with recycled polyethylene and compatibilizing additives, were explored. The effects of composition and processing on the thermal, mechanical, and morphological properties of the resulting materials were systematically analyzed. The results show that intense mechanical homogenization and chemical compatibilization are not sufficient to overcome the intrinsic limitations imposed by contamination and compositional variability. As a proof of concept, selected formulations were processed into filaments and tested in fused filament fabrication, demonstrating basic 3D printability. Full article

Microplastic (MP) pollution has emerged as a significant environmental crisis across the Arabian Gulf, driven by rapid urbanization, industrialization, and infrastructure challenges in waste management. Studies indicate that MPs are ubiquitous in nature and are present in different environmental compartments, including coastal waters, sediments, marine biota, and the atmosphere. The region is characterized by high salinity, high UV index, and frequent dust storms that can affect the physical and chemical behavior of plastic debris. A consistent finding across regional studies highlights the fibrous polyethylene (PE) and polypropylene (PP) polymer types as dominant microplastic particles. This prevalence of fibrous MPs highlights the role of secondary microplastics that are derived from the fragmentation of larger plastic items and textile-derived materials as a major contaminant source. Ecological impacts are increasingly observed, with studies reporting MP ingestion in commercially important fish species and the potential for biomagnification into the human food web. However, there exist key knowledge gaps regarding the long-term toxicological impacts on human health. This review synthesizes existing data to improve the understanding of microplastic distribution in Qatar and the Arabian Gulf while highlighting the need for standardized monitoring approaches and appropriate waste management strategies. Full article

Industrialization has caused extensive environmental change, including a global surge in plastic production and pollution. This has resulted in the accumulation of microplastics (MPs; <5 mm) and nanoplastics (NPs; <1 μm) in ecosystems worldwide. MPs originate from both primary sources, such as cosmetics and industrial applications, and secondary sources, through the degradation of larger plastic debris. As a result, MPs and NPs have become ubiquitous contaminants, posing significant toxicological risks to living organisms. These persistent pollutants are diverse polymers that vary in size, shape, and chemical composition, making their impacts on organism physiology complex and difficult to disentangle. Plastic pollution is particularly severe in aquatic environments, where particles accumulate from terrestrial sources such as urban dust, agricultural runoff, industrial discharges, and wastewater effluents. Although most research has centered on marine ecosystems, emerging evidence indicates that freshwater environments may contain comparable or even higher concentrations of MPs. Once inside the body, MPs can translocate into tissues and exert toxic effects on multiple organ systems. Collectively, plastic pollution poses not only physiological but also neurological and behavioral risks to aquatic life, with potential consequences for ecosystem stability and trophic interactions. Both MPs and NPs are sufficiently small to cross the blood–brain barrier, raising concerns about their potential impacts on the nervous system by interfering with neuronal function and brain development. Plastic particles can accumulate in neural tissues, inducing oxidative stress, neuroinflammation, and disruption of neurotransmitter signaling. Such neurotoxic effects are linked to altered locomotion, feeding, predator avoidance, and social behaviors across multiple species. This review examines current evidence on the neurotoxic effects of plastic pollution in aquatic organisms and underscores the urgent need for further research and action to mitigate its impact. In light of escalating plastic production and inadequate waste management, the growing evidence that MPs and NPs disrupt aquatic nervous systems, behavior, and ecosystem stability underscores an urgent need for intensified research, improved mitigation strategies, particularly for nanoplastics, and the accelerated development of truly safe and sustainable alternatives. Full article

Plastic pollution, particularly in marine environments, has become a major global concern; therefore, monitoring and controlling these contaminants is essential to safeguard ecosystem integrity and human health. This study evaluates the ability of Posidonia oceanica spheroids to incorporate and retain plastic debris, with a particular focus on microplastics (MPs). A total of 1300 spheroids were collected along the Latium coast (Central Italy); among these, 454 (34.9%) contained plastic debris, with an average of 3.1 items per spheroid. Overall, 1415 plastic items were extracted and identified. Based on size classification, 48.7% were microplastics, 29.6% mesoplastics, and 21.9% macroplastics. Plastic items mainly consisted of filaments (40.9 ± 12.6%) and fibers (21.5 ± 5.2%). Eleven different colors were recorded, with white (28.8 ± 9.1%), transparent (13.4 ± 6.0%), and black (11.1 ± 6.8%) being the most frequent. A strong correlation was observed between the number of plastic items contained in the spheroids and proximity to wastewater treatment plants, which are known sources of synthetic fibers. Fourier transform infrared spectroscopy (FTIR) identified a total of 15 polymer materials, with nylon (18.2 ± 11.0%) and polyethylene terephthalate (PET; 17.3 ± 7.2%) being the most abundant. Structural alterations observed in FTIR spectra, together with carbonyl index values, indicate that most MPs are of secondary origin, resulting from prolonged environmental degradation. These results demonstrate that P. oceanica spheroids effectively promote plastic trapping and highlight their potential as a simple and cost-effective monitoring tool for marine plastic pollution. Full article

Marine plastic pollution poses severe ecological and economic threats, while people with disabilities (PwDs) often face limited meaningful employment opportunities. This study evaluated a unique social enterprise in Japan that addresses both challenges through upcycling marine plastic waste into accessories while providing employment for PwDs. Using the Social Return on Investment (SROI) methodology, we assessed the project’s social and environmental impacts over one year (2020). Data was collected through stakeholder surveys, interviews, and operational records. The analysis identified 15 outcomes across six stakeholder groups, including income generation, environmental awareness-raising, and sustained volunteer engagement. The project achieved an SROI ratio of 3.50, indicating that every JPY 1 invested generated JPY 3.50 in social value. Media exposure (30.5%), employment income (25.6%), and volunteer motivation (18.5%) comprised 74% of the total value. Despite processing only 50 kg of marine plastic annually, the project demonstrated significant symbolic impact through behavior change and public awareness. Key challenges include limited production capacity, wage constraints, and gender-biased consumer demographics. This case illustrates how small-scale, community-based upcycling initiatives can generate multidimensional social value by integrating environmental conservation with social inclusion objectives. Full article

Detecting underwater debris is important for monitoring the marine environment but remains challenging due to poor image quality, visual noise, object occlusions, and diverse debris appearances in underwater scenes. This study proposes UDD-YOLO, a novel detection framework that, for the first time, applies a diffusion-based model to underwater image enhancement, introducing a new paradigm for improving perceptual quality in marine vision tasks. Specifically, the proposed framework integrates three key components: (1) a Cold Diffusion module that acts as a pre-processing stage to restore image clarity and contrast by reversing deterministic degradation such as blur and occlusion—without injecting stochastic noise—making it the first diffusion-based enhancement applied to underwater object detection; (2) an AMC2f feature extraction module that combines multi-scale separable convolutions and learnable normalization to improve representation for targets with complex morphology and scale variation; and (3) a Unified-IoU (UIoU) loss function designed to dynamically balance localization learning between high- and low-quality predictions, thereby reducing errors caused by occlusion or boundary ambiguity. Extensive experiments are conducted on the public underwater plastic pollution detection dataset, which includes 15 categories of underwater debris. The proposed method achieves a mAP50 of 81.8%, with 87.3% precision and 75.1% recall, surpassing eleven advanced detection models such as Faster R-CNN, RT-DETR-L, YOLOv8n, and YOLOv12n. Ablation studies verify the function of every module. These findings show that diffusion-driven enhancement, when coupled with feature extraction and localization optimization, offers a promising direction for accurate, robust underwater perception, opening new opportunities for environmental monitoring and autonomous marine systems. Full article

Marine plastic pollution represents a critical ecological challenge, exerting long-lasting impacts on ecosystems, biodiversity, and human well-being. This study introduces the DEEP-PLAST project, an integrated AI-based framework designed for the detection and trajectory prediction of floating marine plastic waste using open-access Sentinel-2 satellite imagery and environmental models of ocean currents and wind. The DEEP-PLAST methodology integrates object detection (YOLOv5 on UAV data), semantic segmentation (U-Net/U-Net++ on Sentinel-2), and drift simulation using Copernicus and NOAA datasets. U-Net++ achieved the best performance (F1 = 0.84, false positive rate 5.2%), outperforming other models. Detected debris locations were linked to Lagrangian drift models to identify accumulation zones in the Black Sea, supporting targeted cleanup efforts. While promising, drift validation remains qualitative due to limited ground truth, to be addressed in future work with in situ and NGO data. This approach supports EU Mission Ocean, the Marine Strategy Framework Directive, and UN SDGs, demonstrating the potential of AI and remote sensing for marine protection. Future efforts will expand datasets, apply the platform to other seas, and launch a web tool for NGOs and policymakers. Full article

Accumulation of plastic debris in marine environments has become a critical global issue, with microplastics (MPs) posing persistent ecological risks. This review synthesizes current knowledge on the formation mechanisms of MPs from polyolefins such as polypropylene (PP) and polyethylene (PE), emphasizing the influence of marine conditions on degradation pathways. Autoxidation is identified as the dominant mechanism; however, salinity and chloride ions significantly retard radical formation, altering photodegradation kinetics and crack propagation. These effects lead to distinctive surface morphologies—such as rectangular and trapezoidal crack patterns in PP—which can serve as reliable indicators for polymer identification. This review further explores the role of polymer chain orientation and spherulite structures in crack development and discusses how these features can be leveraged for cost-effective sorting and recycling strategies. Finally, emerging approaches using AI-based image recognition for automated identification of weathered plastics are highlighted as promising tools to enhance resource recovery and mitigate marine plastic pollution. Full article

Plastics have become a ubiquitous feature of modern life, with their presence continually increasing. This widespread use has led to the global proliferation of plastics, including contamination of aquatic environments. This review focuses on microplastics—plastic particles less than 5 mm in size—in the Northern Gulf of Mexico. The central objective was to evaluate the abundance and potential impacts of microplastics in the region. Findings appear to indicate that microplastic concentrations in the water are below global averages, while concentrations in shoreline sediments are slightly above average. Although it appears fewer biological specimens contain microplastics in this region, the number of plastic particles per specimen appears higher compared to global observations. Microplastics significantly delay the transition of dissolved organic matter to particulate organic matter (by more than 200%), bioaccumulate in organisms, serve as adsorption surfaces for toxins and pollutants, and cause a range of biological effects. Further research is necessary to accurately quantify microplastic pollution and evaluate its ecological and environmental impacts. Full article

This study quantifies how pressurized water immersion alters the reciprocating sliding behavior of glass and Kevlar woven fabric-reinforced polymer hybrid composite laminates. Specimens were immersed in deionized water at 10 bar and 25 °C for 0, 7, 14, and 21 days, then tested against a 6 mm 100Cr6 steel ball at 20 N under four regimes that combine 1 or 2 Hz with 10 m or 20 m total sliding. Water uptake rose from 0 to 8.54% by day 21 and followed a short-time Fickian square root of time trend, indicating diffusion-controlled sorption. The coefficient of friction exhibited a robust nonmonotonic response with a pronounced minimum at 14 days that was typically 20 to 40% lower than the unaged reference across frequencies and distances, while 7 days produced a partial decrease and 21 days trended upward. Three-dimensional profilometry showed progressive widening and deepening of wear tracks with immersion, for example, at 1 Hz and 10 m width increased from about 1596 to about 2050 to 2101 μm and depth from about 128 to about 184 to 185 μm, with a transient narrowing at 2 Hz after 7 days. Scanning electron microscopy corroborated a transition from mild plowing to matrix plasticization with fiber–matrix debonding and debris compaction. Beyond geometric wear metrics, this study re-processed the existing profilometry and COF records to derive a moisture-dependent mechanistic approach. Moisture uptake up to 8.54% reorganizes the third body at the interface so that friction drops markedly at 14 days (typically 20–40% below the unaged state), while concurrent matrix plasticization and interface weakening enlarge the wear cross-section extracted from the same 3D maps, decoupling friction from damage width/depth under wet conditioning. Factorial analysis ranked immersion time as the dominant driver of damage for width and depth with frequency as a secondary factor and sliding distance as a minor factor, highlighting immersion-controlled tribological design windows for marine and humid service. Full article

Microplastics (<5 mm) and nanoplastics (~100 nm), which are invisible to the naked eye, originate primarily from fragmentation and breakdown larger plastic debris are increasingly pervasive in the environment. Once released, they can disperse widely in the environment, pollute them adversely and ultimately be taken up by living organisms, including humans, through multiple exposure pathways. Their distribution in aquatic systems is influenced by their physiochemical properties including density, hydrophobicity, and chemical stability, along with environmental conditions and biological activities. To better understand the dynamics of micro- and nanoplastics in surface water, this study conducted a comprehensive review of 194 published articles and scientific reports covering marine, freshwater, and wastewater systems. We assessed the abundance, spatial distribution and the factors that govern their behavior in aquatic systems and analyzed the sampling techniques, pretreatment process, and detection and removal techniques to understand the ongoing scenario of these pollutants in surface water and to identify the ecological risks and potential toxicological effects on living biota via direct and indirect exposure pathways. Full article

Macroplastic pollution is a growing environmental concern, threatening the marine environment. Despite growing awareness of marine plastic pollution, few studies have assessed the effectiveness of in situ technologies such as safety nets for macroplastic interception. This study aims to evaluate the effectiveness of safety net (SN) systems in intercepting macroplastic debris in the different zones of recreational Yugang Park Beach (YPB), Zhanjiang Bay, China. Safety nets were installed at stations representing different hydrodynamic conditions, and macroplastic debris (2.5–80 cm) was collected and analyzed for size, color, and shape characteristics. Two survey comparisons revealed a higher debris density in the winter survey (1.8 ± 0.3 items m²) than in the summer survey (1.5 ± 0.3 items m²). Most debris fell within the 10–40 cm range, with transparent low-density polyethylene plastic bags being the dominant type, particularly in the winter survey (80.7%). Statistical analysis indicated that plastic size was likely related to net retention characteristics, while tidal influences accounted for a major portion of spatial variability in debris accumulation. These findings suggest that SN systems are effective tools for macroplastic interception and could inform evidence-based coastal management strategies to reduce plastic pollution in similar coastal environments. Full article