Search Results (101)

Nano- (NPs, <1 µm) and microplastics (MPs, 1 µm–5 mm) are ubiquitous contaminants whose toxicity to invertebrates carries implications at the individual scale and (although not yet quantitatively validated) at the population scale. This semi-systematic narrative review organizes available evidence within an adverse outcome pathway (AOP) framework, linking primary molecular initiating events (MIEs) to adverse outcomes while flagging evidence strength at each step. It involves a structured synthesis that applies selected PRISMA 2020 transparency principles, namely disclosed databases, a priori eligibility criteria, and explicit harvest and de-duplication counts, but does not attempt the exhaustive paired screening, formal risk-of-bias scoring, or quantitative meta-analysis of a full systematic review; this design was chosen because the marked heterogeneity of particle physicochemistry, exposure regimes, and endpoint metrics across the available literature makes pooled statistical synthesis premature. Evidence is appraised across Daphnia, Artemia, Chironomus, Caenorhabditis elegans, Eisenia, marine mollusks, and crustaceans. Polymer chemistry, size, surface charge, weathering, biofilm formation, additives, and adsorbed co-contaminants shape uptake and downstream toxicity. Reactive oxygen species, mitochondrial dysfunction, lysosomal destabilization, and ER stress recur as coupled key events downstream of four MIEs (direct membrane interaction, protein corona formation, surface-catalyzed redox chemistry, and Trojan horse delivery). Multi-omics datasets converge on dysregulated stress, repair, apoptotic, immune, and inflammatory programs; epigenetic marks are increasingly considered as substrates for persistent and potentially heritable toxicity, although stable transgenerational transmission remains poorly demonstrated. The review delivers (i) an AOP map with evidence-strength annotations (strong, moderate, emerging), (ii) a structured cross-study synthesis comparing NP and MP effect profiles, and (iii) a critical layer that reinterprets biphasic and apparently contradictory data as mechanistically informative once particle physicochemistry and tissue context are resolved. Progress will depend on standardized characterization, environmentally realistic mixtures, and AOP-anchored designs that distinguish experimentally demonstrated mechanisms from inferred mechanisms and theoretical extrapolations. Full article

Microplastics and nanoplastics (MNPs) have been recognized as ubiquitous emerging global pollutants, which are extensively detectable in diverse environmental media and food matrices. Increasing evidence indicates that the intestine is a primary target of orally ingested MNPs and a critical initiating hub for systemic toxicity. Once ingested orally, MNPs can interact with the intestinal mucus layer and epithelial barrier, induce gut microbiota dysbiosis, remodel bile acid and short-chain fatty acid metabolism, and activate oxidative stress, inflammation, apoptosis, and immune imbalance. These gut-derived disturbances may subsequently propagate adverse signals to distal organs through the gut-liver, gut-brain, gut-kidney, gut-lung, gut-reproductive, and gut-mammary axes. Intestinal barrier dysfunction, endotoxin translocation, abnormal microbial metabolites, and microbiota-derived immune signals constitute common mediating pathways linking local intestinal injury to multi-organ toxicity. In addition, smaller particle size, surface oxidation, environmental aging, bio-corona/plastisphere formation, and co-exposure with other contaminants can further modulate the intensity and specificity of gut-organ axis disruption. Prior reviews are limited to separate analyses of single-organ toxicity or isolated gut-organ pathways. To fill this gap, this work synthesizes contemporary mechanistic and experimental evidence to establish a gut-initiated systemic toxicology framework for MNPs. We differentiate direct particle translocation from gut-derived indirect signaling, evaluate the varying robustness of supporting evidence for each gut-organ axis, and underscore nanoscale biointerface properties as key modulators of MNPs systemic toxic potency. Full article

Chewing gum is a frequently neglected polymer-containing consumer product that can be considered a source of microplastic exposure during chewing, and, upon disposal, a cause of surface contamination. This narrative review summarises the composition of the gum base, particle release during mastication, environmental fate, and the emergence of circular upcycling. Modern gum bases can be characterised by water-insoluble elastomeric and resinous phases designed for mechanical durability, as demonstrated by established evidence. Furthermore, a recent experiment has demonstrated the release of detectable microplastic-sized particles into the saliva after chewing. However, quantitative estimates, such as the apparent highest value of 637 MPs g⁻¹, and the observation that the majority of particles detected are released during the first 8 min, remain tentative, given the limited range of products offered and the lack of replication across different brands, formulations, chewing schedules, and analytical tools. Another proof point that samples of natural and synthetic gums have comparable particle discharge indicates that no amount of natural or plastic-free labelling should mean no particle exposure. The adhesive and hydrophobic nature of gum residues, along with observations of microbial colonisation and surface interaction, is also a key factor for their persistence post disposal. Since no standardised gum disintegration protocols exist, outdoor residence times are unknown. Other under-characterisations occur in nano- and ultra-small plastic fractions, as standard spectrometric analyses have size limits. Emerging materials engineering work indicates that sanitised, chewed gum can be reprocessed with conductive nanofillers to serve as flexible sensing agents. These circular paths are proof-of-concept paths at this point, as we must confirm oxidation stability, cleanliness, scalability, logistics, collection, and lifecycles. This study clearly distinguishes well-known polymer and litter issues from new exposure, degradation, and upcycling proposals. Full article

With the widespread application of new chemicals, the concentration of emerging contaminants (ECs), such as antibiotics, per- and polyfluoroalkyl substances (PFAS), microplastics, and new pesticides, in aquatic environments is on the rise. ECs such as those examined in the studies exhibit high toxicity, persistence, and a propensity for bioaccumulation, which can lead to significant risks for ecosystems and human health. Traditional water treatment technologies exhibit limited removal capabilities for ECs, whereas micro-nano bubbles (MNBs) exhibit great potential in the field of ECs treatment, due to their unique physicochemical properties. This article systematically reviews the research progress on the treatment of ECs using MNBs combined with other technologies, including physical methods (adsorption enhancement), chemical methods (ozonation, persulfate oxidation, photocatalysis, and material catalysis) and biological methods (microbial synergy). This review summarizes the research progress and mechanisms of MNBs combination technologies, outlining the critical knowledge gaps and future research perspectives to advance the rational design and engineering application of MNBs for ECs’ elimination in water treatment. Full article

Polystyrene (PS), particularly expanded polystyrene (EPS), is an environmentally significant commodity polymer that contributes substantially to secondary microplastic and nanoplastic pollution through environmental weathering and fragmentation. During aging, PS undergoes nano-scale physicochemical transformations, including chain scission, surface oxidation, and the formation of oxygen-containing functional groups, which profoundly influence its environmental fate, microbial colonization, and biodegradation behavior. Conventional remediation technologies remain energy-intensive and often fail to achieve complete mineralization, highlighting the need for sustainable and integrated remediation strategies. Recent studies have demonstrated that diverse microorganisms, including Pseudomonas, Rhodococcus, Bacillus, and Exiguobacterium, can colonize PS surfaces and initiate oxidative depolymerization through extracellular biofilm formation and oxidative enzymes such as styrene monooxygenase, laccases, and peroxidases. In parallel, insect-based systems, particularly Tenebrio molitor and Zophobas morio, provide unique biological platforms in which gut microbiota facilitate partial PS degradation and mineralization through synergistic host–microbe interactions. This review critically integrates recent advances in nano-scale PS transformation, microbial colonization, oxidative enzymatic pathways, insect gut-mediated biodegradation, and advanced analytical techniques used to characterize degradation processes. Emphasis is placed on nano–bio interactions and emerging nanotechnology-enabled remediation strategies, including engineered microbial consortia, biofilm-based bioreactors, and nanomaterial-assisted treatment systems. Finally, current limitations and future research priorities are discussed, including degradation kinetics, byproduct toxicity, standardized evaluation methods, and the integration of biological and nanomaterial-based approaches for scalable PS microplastic remediation. Full article

Nano-/microplastics (NMPs) accumulation in agricultural soils has become a growing environmental concern due to its negative impacts on soil health, crop productivity, and food safety. Biochar has gained considerable attention as a sustainable soil amendment capable of improving soil quality and mitigating emerging pollutants. This review examines the role of biochar and modified biochar in reducing the mobility, bioavailability, and plant uptake of NMPs through adsorption, aggregation, and immobilization mechanisms. In addition, biochar improves soil fertility by enhancing nutrient retention, water holding capacity, soil structure, and microbial activity, while also contributing to climate change mitigation through carbon sequestration. However, certain biochars may negatively affect saline–alkaline soils because of their high pH and salinity. Generally, biochar application offers multiple environmental benefits, including soil restoration, pollutant mitigation, and enhanced agricultural sustainability. This review synthesizes recent advances in understanding the mechanisms by which biochar influences NMPs behavior in soil–plant systems and highlights current knowledge gaps and future research directions needed to support its effective application in sustainable agriculture. Full article

Sunlight-driven UV weathering is a major transformation pathway of environmental microplastics, promoting surface oxidation, molecular degradation, embrittlement, and progressive fragmentation toward smaller size fractions. However, comparisons across studies remain difficult because weathering is often described using descriptors that probe different aspects of degradation without being clearly distinguished. Surface-sensitive oxidation metrics, such as carbonyl or oxidation indices (CI/OI), are frequently emphasized, whereas fragmentation and embrittlement are more directly governed by bulk molecular-weight loss, mechanical weakening, and particle-size evolution. This review examines UV weathering of common polymers through a coupled chemico-mechanical perspective relevant to the micro-to-nano transition. We distinguish surface chemical descriptors, bulk molecular and mechanical descriptors, and fragmentation-related metrics, and critically assess the analytical methods used to measure them, including FTIR, Raman spectroscopy, GPC/SEC, thermal methods, mechanical testing, and particle-size analyses. We argue that no single metric is sufficient to describe weathering progression, and that meaningful interpretation requires joint reporting of oxidation state, Mn/Mw changes, mechanical deterioration where available, and particle-size distribution as a function of cumulative or spectrum-weighted UV dose. We further propose a minimal QA/QC reporting framework including UV metadata, temperature, oxygen availability, blanks, replicates, recovery tests, and matrix-specific detection limits. By separating what different methods actually probe and linking them to fragmentation mechanisms, this review provides a more operational basis for interpreting UV-aged microplastics in environmental sampling and biomonitoring. Full article

Soils are increasingly affected by microplastic (MP) contamination, mainly coming from industrial activities, agricultural practices, atmospheric or waterborne transport, and improper waste disposal. Despite the increasing attention to the fate of MPs in soil over the last few years, research in this area is still limited compared to aquatic ecosystems. The introduction of MPs into the soil environment can modify not only the soil properties but also the interactions among soil components, plants, and microorganisms, thus affecting the mobility and availability of other contaminants, such as potentially toxic elements (PTEs). This review critically examines the complex dynamics between MPs and PTEs in the soil ecosystem, with a focus on the conditions under which MPs can act as a source or a sink of PTEs. Indeed, on the one hand, MPs can adsorb or complex PTEs on their surfaces (similarly to natural soil colloids), thus reducing their mobility and availability; on the other hand, they can release/mobilize PTEs after MP degradation or act as micro-/nano-vectors of PTEs. Understanding such mechanisms is relevant when evaluating the environmental risks associated with the co-presence of MPs and PTEs in soil, a situation likely to occur in most contaminated sites and in many agricultural soils. Full article

Micro- and nanoplastics (MNPs) are ubiquitous environmental pollutants recognized as emerging and relevant risk factors for numerous human diseases, including cardiovascular diseases. MNPs enter the human body through ingestion, inhalation, and dermal penetration, and their toxicity varies according to size, shape, and chemical composition, most notably between microplastics (>1 µm) and nanoplastics (<1 µm), which differ in cellular uptake mechanisms and biodistribution. Recent evidence has confirmed their presence in cardiac and vascular tissues, raising significant concerns about their potential impact on human health. This review summarizes current knowledge on MNP exposure sources, physicochemical properties, and systemic bioavailability, with a particular emphasis on the mechanisms of transport that facilitate their deposition within the myocardium and vasculature. It further addresses a broad spectrum of cardiotoxic effects, including oxidative stress, mitochondrial injury, immune activation, ion channel disruption, cell death, and fibrosis. Endothelial dysfunction, vascular injury, and pro-atherogenic activity are also discussed. In addition to outlining existing detection techniques and emerging in vitro models, the review highlights initial steps toward the development of preventive strategies. Concluding with key knowledge gaps and future research directions, this article underscores the urgent need for standardized measurement tools, deeper insights into damage mechanisms, and clinical interventions to prevent MNP-induced cardiovascular diseases. Full article

The current approach to coastal oyster reef restoration currently relies on conventional plastics, raising concerns about plastic pollution. Therefore, developing biodegradable alternatives, such as nano-montmorillonite-modified polylactic acid materials (PLA), has become a priority. This study compared oyster recruitment on PLA substrates with that on four conventional plastic substrates (polyethylene (PE), polyvinyl chloride (PVC), polyethylene terephthalate (PET) and polyvinylidene chloride (PVDC)) through field experiments, examining how PLA substrate thickness and surface roughness influence oyster recruitment. Additionally, we evaluated the responses of oyster populations and associated macroinvertebrate communities after ten months of restoration using PLA-based versus polyethylene (PE) shell-bag reefs. The results showed no significant difference in oyster recruitment between PLA and conventional plastic substrates (p > 0.05). However, increasing the thickness and surface roughness of the PLA substrates significantly enhanced the recruitment of juvenile oysters (p < 0.05). After ten months, there was no significant difference in oyster abundance between PLA and PE shell bag reefs; however, there was a significant difference in resident macroinvertebrate abundance, with abundances markedly higher on PLA reefs (1372 ± 220 ind./m² vs. 545 ± 90 ind./m²; p < 0.05). This study highlights the potential of PLA as a promising alternative to conventional plastics. However, its rapid degradation limits its applicability in high-energy environments. Furthermore, given that a comprehensive assessment of the microplastic risks associated with its degradation has not yet been conducted, large-scale application is not currently recommended. Full article

Introduction: It is accepted that nano- and micro-plastic (NMP) pollutants threaten ecosystems and human health by their bioaccumulation but, interestingly, their toxicity is shape-dependent. However, a clear definition of irregular NMPs, as the dominant shape in environmental and biological samples, is currently lacking when compared to spherical and fibrous NMPs. Objectives: This study quantifies morphometric descriptors in order to develop a standardized definition for irregular NMPs. Methods: Hyperspectral images of 34 spherical, 50 fibrous, and 45 irregular NMPs were collected from the literature. All shape-related features reported previously were analyzed using a machine learning model. Using five-fold cross-validation, a decision tree-based ensemble classifier with fixed parameters and Gini coefficient was established to screen key morphometric descriptors and their optimal interval ranges. The model was independently validated, enabling the accurate distinction of irregular NMPs from spherical and fibrous NMPs. Results: Three morphometric descriptors, including circularity, roundness, and perimeter-to-area ratio, were identified using five-fold cross-validation as optimal indicators for NMP shape classification. Optimal interval ranges for irregular NMPs were as follows: circularity (0.388 ± 0.004–0.768 ± 0.004), roundness (0.248 ± 0.01–0.752 ± 0.06) and perimeter-to-area ratio (>11.608 ± 1.39). This approach generated a 96.0% macro-averaged accuracy across these NMPs, with 100% precision and 89.0% recall. Conclusions: Irregular NMPs may be characterized using three morphometric descriptors, such as circularity, roundness, and perimeter-to-area ratio. The three-descriptor combination has highly accurate discrimination from spherical and fibrous NMPs. Full article

This review examines microplastics (MPs) in aquatic environments, their interactions with organic pollutants (OPs), effects on organisms, and implications for human and ecological health. MPs are ubiquitous, persistent contaminants. Their small size and large surface area enhance adsorption of diverse OPs; however, the extent to which MPs influence pollutant transport, fate, and bioavailability remains highly context-dependent and is still under scientific debate. Sorption processes are influenced by polymer type, pollutant properties, environmental factors, and aging processes that increase surface reactivity, further contributing to the variability of MP–OP interactions. Detection of MPs in human tissues raises concerns about long-term health effects, including inflammatory, immune, gastrointestinal, respiratory, and endocrine responses. Despite advances in analytical techniques, challenges remain in identifying and quantifying small particles in complex matrices. This review emphasizes the need for integrated, multi-technique, and environmentally realistic studies to understand MP–OP interactions and support risk assessment. Future research should focus on standardizing methodologies, improving nano-sized particle detection, and elucidating long-term effects, including trophic transfer and potential tissue accumulation. Full article

Nano- and microplastic contamination poses a growing challenge to aquatic environments, driving the need for efficient and sustainable removal technologies. In this study, carbon–silica hybrid nanoparticles (CSNPs) were synthesized from rice husk-derived black liquor via controlled lignin–silica self-assembly followed by thermal carbonization, providing a waste-recycling biorefinery route for value-added material production. Structural characterizations revealed that carbonization generates a hierarchically porous carbon–silica hybrid with enhanced surface area. The CSNPs exhibited rapid and size-dependent adsorption toward nano- and microplastics (200–1000 nm), with optimal performance observed for 500 nm particles. Microscopic observations further demonstrated a size-adaptive capture mechanism, involving pore filling and surface adsorption for nanoplastics and aggregate-assisted encapsulation for larger microplastics. This study highlights CSNPs as low-cost and effective adsorbents for broad-spectrum plastic removal while offering a sustainable pathway for the high-value utilization of black liquor and rice husk biomass in water purification applications. Full article

Micro- and nano-plastic pollution caused by the mismanagement of plastics waste is a significant problem worldwide, causing severe impacts in aquatic and terrestrial environments. The purpose of this study was to evaluate the adsorption capacity of a thermally stable and superhydrophobic bio-substrate to remove microplastic particles (MPPs) from aqueous systems. In this work, the adsorption efficiency of cattail fluff towards MPPs from pristine PP, PVC, PA6, LDPE, HDPE, and their blend was evaluated. The effect of temperature (30 °C, 40 °C, and 50 °C) and two binding environments (distilled water and industrial wastewater) on adsorption was determined. Non-linear regressions of seven adsorption isotherm models including Langmuir, Freundlich, Temkin, Dubinin–Radushkevich (D–R), Redlich–Peterson (R–P), Toth, and Sips were applied to fit the experimental data. Error function analysis confirmed that the D–R adsorption isotherm model offers the best fit of the experimental data. The results show that the bio-substrate is very effective in adsorbing MPPs from aqueous systems with adsorption capacities of q_e = 3597 mg/g and q_e = 2807 mg/g in distilled water and synthetic industrial water, respectively. The composition of the MPPs determines the effect of temperature and binding environment on the adsorption performance of the bio-substrate. Physisorption dynamics for the MPP/bio-substrate system are also provided and discussed. Overall, the hydrophobic bio-substrate is highly effective in removing MPPs from aqueous systems, with the added advantages of low cost, sustainability, and scalability for practical applications. Full article

Microplastics (MPs) and nanoplastics (NPs) have emerged as pervasive contaminants across diverse environments—including soil, water, and the atmosphere—posing substantial risks to resident organisms. Concurrently, alien plant invasion represents a significant driver of environmental change, introducing considerable ecological risks to terrestrial ecosystems. Synthesizing evidence from 26 original research articles, this review examines the bidirectional interactions between micro(nano)plastics (MNPs) and terrestrial invasive plants. A growing body of evidence indicates that MNPs alter the growth and performance of both invasive and native plants. In most documented cases, MNPs appear to enhance the competitive ability of invasive plants, thereby elevating their invasion potential. However, counterexamples exist wherein MNPs strengthen the competitiveness of native plants, consequently mitigating invasion risk. These divergent outcomes are likely attributable to a suite of influencing factors, notably the characteristics of the MNPs (e.g., type, size, concentration), the specific invasive and native plant species involved, and variations in experimental conditions. Key mechanistic pathways involve MNPs-induced disturbances in soil microecology—particularly nutrient dynamics and rhizosphere microbiomes—and allelopathic interactions. Conversely, invasive plants may adsorb/absorb MNPs and subsequently modify their environmental fate and behaviors (e.g., degradation, transport). Finally, we delineate critical knowledge gaps and propose prioritized directions for future research. This review advances our understanding of the ecological risks associated with plant invasions in an era of pervasive MNP pollution and offers a scientific foundation for developing informed management strategies. Full article