Potential Health Impact of Environmentally Released Micro- and Nanoplastics in the Human Food Production Chain: Experiences from Nanotoxicology

Microplastic abundance and characteristics in bivalves from Tam Giang-Cau Hai and O Loan Lagoons, coastal regions in Central Vietnam: Implication on human health

Four common bivalves, including white clam (Meretrix lusoria), lined clam (Paratapes undulatus), oysters (Crassostrea gigas), and green mussels (Perna viridi), which are commonly consumed in Central Vietnam, were collected from Tam Giang-Cau Hai and O Loan Coastal Lagoons. The samples were investigated for the presence of microplastics (MPs) in their tissues. The average number of MPs determined in white clams, lined clams, oysters, and green mussels in Central Vietnam varies from 0.3 to 0.9 per g-ww and from 0.9 to 5.6 per individual. Fibers, fragments, and pellets were found with various proportions concerning. Fibers were the most common shape, making up 36-74 % of the total microplastics, followed by fragments accounting for 16-47 %. The most prevalent colors were white-transparent and black-grey, comprising 49-81 % of the MPs. Regarding the microplastics found in the bivalve tissues, 78-80 % were <500 μm. Given chemical analysis, rayon accounted for 38 % of the microplastics discovered in bivalve tissues; closely PET (13 %), PA (10 %), and PP (10 %) were followed. This study offers valuable insights into the microplastic contamination concerned by bivalve consumption in Thua Thien Hue and Phu Yen, Central Vietnam; the results estimate the annual intakes are between 5000 and 10,000 particles per person. Unprecedentedly addressed in the literature, these findings contribute to a better understanding of microplastic pollution in Vietnam. The results altogether provide solid shreds of evidence for the MP contamination in Vietnam-based seafood, thus encouraging further attempts for plausible socio-economical regulations and raising public awareness on the issue.

Concentration-dependent effects of polystyrene microplastics on methanogenic activity and microbial community shifts in sewer sediment

Microplastics (MPs) are emerging environmental contaminants that interfere with microbial processes, yet their effects on methanogenesis in anaerobic systems remain insufficiently understood. This study investigates the impact of polystyrene microplastics (PS-MPs) on methanogenesis, microbial community structure, and metabolic pathways in simulated sewer sediment systems, with exposure concentrations of 5, 50, and 250 mg·L-1. The results revealed a concentration-dependent effect of PS-MPs on methanogenesis: a 222.2 % increase at 5 mg·L-1, and 72.2 % and 88.9 % increases at 50 mg·L-1 and 250 mg·L-1, respectively, indicating a non-linear response. PS-MPs exposure enhanced coenzyme F420 (F420) activity, a key indicator of methanogenic activity, but also inhibited methyl coenzyme M reductase (Mcr), disrupting critical methanogenic pathways. At lower concentrations, PS-MPs promoted the abundance of hydrogenotrophic methanogens, whereas higher concentrations suppressed overall methanogenic activity. Furthermore, PS-MPs had a dose-dependent effect on CH4 oxidation, influencing the structure of methanotrophic communities. These findings establish a clear dose-response relationship between PS-MPs concentration and CH4 dynamics in anaerobic systems, highlighting the complex role of microplastics in methanogenesis and microbial interactions. This research provides valuable insights into the environmental implications of microplastics in wastewater systems and their potential impacts on biogas production and CH4 mitigation, aligning with the objectives of environmental bioengineering and sustainable waste management.

Enhanced gut damage and microbial imbalance in bullfrog tadpoles (Lithobates catesbeiana) exposed to polystyrene microplastics under high-temperature conditions

The potential threat posed by microplastic pollution to ecosystems has garnered widespread attention. Additionally, the combined effects of climate warming and environmental pollutants may further exacerbate the negative impacts on aquatic organisms. In this study, the effects of polystyrene microplastics (PS-MPs) on the oxidative stress status, inflammatory response, and gut microbiota composition of bullfrog tadpoles (Lithobates catesbeiana) were systematically evaluated under different temperatures. Histological analysis, various biomarkers, and microbiome methods were used. Tadpoles were exposed to 0 (control), 100, and 1000 μg/L of PS-MPs at both 25 °C and 32 °C for 28 days. The results showed that compared to low-temperature conditions, PS-MP exposure under high-temperature conditions significantly increased the total antioxidant capacity, glutathione, acid phosphatase, and lysozyme levels in the gut. Additionally, PS-MP exposure under 32 °C significantly disrupted the intestinal epithelial cell structure and increased the expression levels of pro-inflammatory factor genes. Gut microbiota analysis showed that the abundance of Cetobacterium continuously increasing with the concentration of PS-MPs. Under high-temperature conditions, PS-MP exposure further led to a decrease in microbial community diversity. These findings indicate that high-temperature environments exacerbate the negative effects of PS-MP exposure and enhance the oxidative stress and inflammatory response in the intestines of bullfrog tadpoles, which may be the primary factor leading to gut microbiota dysbiosis. This study provides scientific evidence for assessing the environmental risks of microplastics and formulating corresponding environmental protection measures, highlighting the urgency of addressing combined environmental stressors in the context of global warming.

Profiling of lincRNAs and differential regulatory mechanisms in response to nanoplastic toxicity at environmentally relevant concentrations in Caenorhabditis elegans

Polystyrene nanoplastics (PS-NPs) at environmentally relevant concentrations have been shown to be toxic to living organisms, but the role of long noncoding RNAs (lncRNAs) in their toxicity regulation is not yet clear. Using Caenorhabditis elegans (C. elegans) as a model organism, we investigate the mechanisms and roles of lncRNAs in PS-NPs toxicity at environmentally relevant concentrations. In this study, L1 larvae were exposed to 1-100 µg/L of 50 nm PS-NPs for 72 h, and high-throughput transcriptome sequencing was performed. Exposure to PS-NPs at concentrations of 10 µg/L, which is in the range of environmentally relevant concentrations of nanoplastics, or higher can lead to increased reactive oxygen species (ROS) production and decreased locomotion behavior in C. elegans, yet no significant toxic effects were observed for the leachate. The sequencing results revealed significant changes in G protein-coupled receptors and long intergenic noncoding RNAs (lincRNAs), which warranted further investigation. Additionally, a CRISPR-based knockout (KO) mutant library of C. elegans lincRNAs was employed for in-depth mechanistic studies. The findings indicate that multiple lincRNAs are involved in the regulatory response to the toxic effects of PS-NPs. Compared to wild-type nematodes, linc-7, linc-9, linc-13, linc-21, linc-24, linc-49, linc-61, and linc-169 KO nematodes exhibited increased sensitivity to the toxicity of PS-NPs, while linc-11 and linc-50 nematodes showed resistance. Notably, our results indicate that the transcription process of linc-11, rather than its mature transcripts, played a crucial role in the response to PS-NPs. This is evidenced by the differing phenotypes observed in RNA interference (RNAi) knockdown (KD) and CRISPR KO nematodes following exposure to PS-NPs. Our results suggest that transcriptional regulation involving lncRNAs is integral to the organism's response to PS-NPs.

Aging Changes the Vector Effects of Various Microplastics on the Bioaccumulation of Decabromodiphenyl Ethane in Earthworms

The widespread use and nonstandard disposal of plastic products led to inevitable copollution of microplastics (MPs) and novel brominated flame retardants (NBFRs). However, gaps remain in understanding the influence of aged MPs on the bioaccumulation and biotoxicity of NBFRs in terrestrial environments. We assessed the effects of UV-aged MPs derived from poly(lactic acid) (PLA) and polyethylene (PE) on the bioaccumulation of decabromodiphenyl ethane (DBDPE) in a soil-earthworm system. After 28-d exposure, DBDPE bioaccumulation in the intestine of earthworms under coexposure (0.1% or 1% MPs in 10 mg kg-1 DBDPE soil) exhibited better impacts of MPs than that in the whole tissue. Overall, the aging of biodegradable PLA-MPs promoted DBDPE bioaccumulation in the intestine of earthworms through ingestion and thus reduced DBDPE attachment on the aged PLA-MPs in soil, which relied on their increased adsorption to DBDPE. Similarly, the aging of PE-MPs reduced DBDPE bioaccumulation in the intestine due to the decreased adsorption ability to DBDPE. Specifically, aged PLA-MPs increased DBDPE in the intestine by 15%, while aged PE-MPs decreased it by 21%. Aged PE-MPs formed stable biofilms in soil with strong binding to DBDPE, thereby reducing DBDPE bioaccumulation in earthworms but exacerbating its migration risks. This reflected the "vector effect" of aged MPs on DBDPE bioaccumulation in earthworms with ingestion. Furthermore, SR-FTIR confirmed that MPs remained in tissues and DBDPE was loaded on the MPs' surface in the intestine, indirectly verifying the vector effect of MPs. This work highlights discrepant risks between biobased degradable and fuel-based hydrocarbon MPs in HOC-contaminated soil in realistic environmental scenarios.

New Evidence for the Mechanisms of Nanoplastics Amplifying Cadmium Cytotoxicity: Trojan Horse Effect, Inflammatory Response, and Calcium Imbalance

Nanoplastics (NPs) are emerging pollutants worldwide. Particularly worrisome is that although studies have reported that NPs can amplify the biotoxicity of environmental pollutants, the specific mechanism remains unclear. Here, we found that NPs, even without significant toxicity (cell survival: 99.11%), amplified the hepatocyte toxicity of Cd2+. Mechanistically, higher Cd2+ uptake (Δ = 23.80%) combined with crucial intracellular desorption behavior of Cd2+ loaded in NPs (desorption rate: 82.70%) were identified as prerequisites for NPs amplifying Cd2+ cytotoxicity. As for toxigenic pathways, the inflammatory response and calcium (Ca) signaling pathway were identified as the primary molecular events leading to the amplification of Cd2+ cytotoxicity. Further phenotypic monitoring revealed that NPs synergized with Cd2+ to induce more severe pyroptosis and apoptosis by activating the inflammatory caspase-1-dependent and Ca2+-mitochondrial-caspase-3 pathways to a greater extent, respectively. This study reveals and proves for the first time the "Trojan horse" effects of NPs, thus elucidating the actual mechanisms by which NPs act as toxicity amplifiers of pollutants, providing significant insights into accurate risk assessment of NPs in composite pollution.

Determinants of single-use plastic bottled water consumption among university students: a cross-sectional study

Single-use plastic bottled water (SUPBW) is a major contributor to microplastic pollution. This study aimed to investigate factors influencing university students' consumption of SUPBW. This cross-sectional survey, conducted during the 2023-2024 academic year at the country's largest public university, used a self-administered online questionnaire and convenience sampling. The questionnaire was developed based on the Theory of Planned Behavior (TPB) and the Knowledge, Attitude, and Practices (KAP) frameworks. It included sections on general information, knowledge of environmental and health impacts, TPB constructs, and consumption behavior. Descriptive and regression analyses were conducted to identify factors associated with SUPBW (SUPBW) consumption. The study included 438 participants. Factors that were significantly associated with frequent SUPBW consumption included undergraduate enrolment (OR = 2.33, p-value = 0.02); higher household income (OR = 1.64, p-value = 0.02); lack of environmental literacy from courses (OR = 1.87, p-value < 0.01), initiatives (OR = 1.22, p-value = 0.021), and workshops (OR = 1.51, p-value < 0.01); peer pressure (OR = 3.86, p-value < 0.001); subjective norms from family and friends (OR = 1.91, p < 0.01); perceived behavioral control (OR = 2.68, p-value = 0.01); convenience (OR = 1.32, p-value = 0.015); and strong intentions to continue use (OR = 2.45, p-value < 0.001). In contrast, higher knowledge of environmental impacts and health impacts were associated with infrequent SUPBW consumption. In conclusion, to reduce SUPBW use, interventions should enhance environmental literacy, counter social pressures, and offer sustainable options.

Risk-based integrated framework for evaluating effects of microplastics to aquatic ecosystems and human health

The widespread presence of microplastics (MPs) in environments and the food web is a serious concern for both aquatic ecosystems and human health. Most studies have used single tool to assess risks primarily to organisms and humans, leaving gaps in comprehensive risk assessments. This study conducted an investigation of MP abundances in surface water and wild oysters from natural estuaries of major rivers in Taiwan. Additionally, the data also used to develop an integrated risk-based framework for evaluating potential risks from organisms to human MP exposure to seafood consumption. We assessed aquatic ecological risk quotients (RQ), oyster mortality exceedance risk (ER), human MP intake exposure, and human liver damage ER. Our data showed that MP abundances ranged from 0.025 to 4.701 items/m3 and 0.015-2.374 items/g (wet weight) in water and oysters, respectively. Although RQ values indicate negligible risk for aquatic ecosystems, but oyster mortality ER results from oysters exposed to MPs showed a 6 % increase in mortality (10 % risk). The probabilistic representation of risk curves of MPs for alanine aminotransferase (ALT) levels in human serum was found to be low, indicating minimal health risk to humans. Overall, our data suggest that relying on a single risk indicator may underestimate potential risks, multi-faceted tools are recommended for assessing organism and human health.

Short-term oral exposure to nanoplastics does not significantly impact the antiviral immune response of the mouse

The increasing prevalence of nanoplastics (NPs) in the environment, particularly polystyrene (PS) nanoparticles, raises concerns regarding their potential impact on human and animal health. Given their small size, NPs can cross biological barriers and accumulate in organs, including those critical for immune functions. This study investigates the effects of short-term oral exposure to 100 and 500 nm PS NPs on the adaptive immune responses during viral infections in vivo, using vesicular stomatitis virus (VSV) and lymphocytic choriomeningitis virus (LCMV) as models. Male and female C57BL/6 mice were orally exposed to PS NP for a period of 28 days, during which they were infected with either VSV or LCMV to study the humoral and cellular responses, respectively. The humoral responses were assessed by measuring total and VSV-specific antibody levels, and splenic immune populations. T cell phenotypes, activation, exhaustion and functionality towards LCMV epitopes were studied as readouts of the cellular responses. Our results demonstrate that short-term NP exposure does not significantly affect the generation or neutralizing capacity of antibodies against VSV, nor the cellular responses directed against LCMV. These findings indicate that, under these conditions, PS NP exposure does not significantly compromise the adaptive immune responses during viral infections, underscoring the value of in vivo models.

Tough and swelling-resistant gellan gum-based biofilms with excellent transparency, surface hydrophobicity and barrier capability

The rising energy and environmental crisis brought by extensive usage of disposable synthetic plastic packaging necessitates the pursuit of ecofriendly packaging materials. Herein, a novel type of biofilms from exopolysaccharide gellan gum (GG) were developed through successive sol-gel transition, hydroalcoholic pretreatment and ionic anchoring before air-drying. Universal electronic testing machine, gravimetry, contact angle meter and UV-visible spectrophotometer were employed to investigate the mechanics, swelling-resistance, surface hydrophobicity and barrier property. The results indicate hydroalcoholic pretreatment ameliorates the toughness of GG films, with the breakage elongation and tensile toughness reaching ~17 % and 9.44 MJ/m3. Metal-ion anchoring bestows swelling-resistance and surface hydrophobicity to GG films. The equilibrium swelling ratio after Fe3+-anchoring dropped to ~150 % in water, in stark contrast with the measurable swelling ratio of those unanchored beyond 2700 % which were followed by loss of dimensional integrity. The surface hydrophobicity is improved significantly with the water contact angle enlarged from 48° to 77° after Fe3+-anchoring. Metal-ion anchoring also improves the water vapor barrier performance, and notably Cu2+/Fe3+-anchoring endows UV light-shielding ability to GG films. The prominent performance along with the environmental friendliness of GG is conducive for future application in single-use packaging materials.

Microplastics in the European native oyster, Ostrea edulis, to monitoring pollution-related patterns in the Solent region (United Kingdom)

Microplastics (MPs) are the most abundant type of debris in the marine environment, creating a significant threat to aquatic ecosystems due to their persistence, ability to absorb organic pollutants and potential ingestion by marine fauna. Shellfish are particularly vulnerable to MPs accumulation as they filter large volumes of seawater, and they become an important route for human exposure to these particles. This study, the first to examine MPs in European flat oyster (Ostrea edulis) populations, aimed to quantify these particles in the gill and digestive tissues of oysters from the Solent region (southern England). Enzymatic digestion using Proteinase-K was used in this study and MPs were identified in every oyster sampled to determine whether differences in abundance, type and size of MPs exist between locations. Oysters near urban areas contained significantly more MPs than those near rural areas. Fibres were the most prevalent type of MPs, with sizes varying across locations. The study found no significant differences in MPs presence between gills and digestive tissues, and an inverse correlation between the size of MPs and oyster size. The presence of MPs in wild O. edulis could be an additional threat to the survival of an already threatened species and may pose health risks for predatory species and human consumers of seafood. The use of O. edulis as a biomonitoring species for marine MPs pollution could help determine the extent, distribution and sources of MPs, potentially informing management strategies to reduce pollution.

Effects of Nanoplastics on Lipid Membranes and Vice Versa: Insights from All-Atom Molecular Dynamics Simulations

We compute the potential of mean force (PMF) between semicrystalline polyethylene (PE) nanoplastics (NPLs) and model POPC and DPPC bilayers, which approximate in vivo membranes, using atomistic simulations. Our work shows that atomistic resolution is required to characterize the NPL and lipid interactions. By analyzing the PMF, we demonstrate that the mechanical properties of membranes, rather than NPL semicrystalline morphologies, govern NPL-membrane interactions. Resistance to NPL penetration arises from the elastic energy of the membrane deformation. The flexible POPC membranes resist NPL translocation, and the brittle DPPC membranes fracture under stress. Using an elastic free energy model, we approximate effective repulsions between lipid membranes and NPLs of various sizes. Our mean first-passage time analysis shows that even small, bare NPLs cannot easily penetrate brittle lipid membranes via passive diffusion, even at high concentrations. However, eco-coronas or other mechanisms, such as endocytosis, may still facilitate the cellular uptake of NPLs and MPLs. While semicrystalline morphologies do not directly impact NPL translocation, they do influence NPL behavior within lipid membranes upon translocation. Semicrystalline NPLs remain intact within lipid membranes, whereas amorphous NPLs can dissolve into the hydrophobic core and alter the elastic properties of the membrane.

Micro- and nano-plastics pollution in the marine environment: Progresses, drawbacks and future guidelines

Marine pollution by micro/nanoplastics (M/NPs) has emerged as a critical global issue, with widespread ecological and economic consequences. Numerous studies have investigated M/NPs pollution in marine environments, but there remains a need to assess progress, identify challenges, and propose future strategies. This review provides updated insights into marine M/NPs, including their sources, detection methods, global data from diverse marine ecosystems, and the challenges in mitigating pollution. The review reveals that the ocean harbors approximately 5.25 trillion plastic debris pieces, with a total of 50-75 trillion plastic and microplastic particles, with deep-sea regions containing up to 4 billion plastic microfibers per square kilometer. Human activities, including industrial practices and aquaculture, are major contributors to M/NPs pollution, which threatens 17% of marine species and incurs an economic loss of 6-9 billion USD. M/NPs are found across various marine habitats, including shorelines, sea floors, water columns, biota, and floating debris. Analyzing nanoplastics is particularly challenging due to their heterogeneous aggregation with other contaminants and their much lower concentrations than natural particles. Key drawbacks in addressing M/NPs pollution include inadequate funding, insufficient regulations, and a lack of policy frameworks on the prevalence, distribution, and sources of M/NPs. There is an increasing focus on utilizing innovative technologies such as artificial intelligence (AI) to monitor, assess risks, and predict the spread of M/NPs. Therefore, urgent global cooperation, involving all stakeholders and the general public, is essential. Additionally, integrating scientific and engineering methods, along with AI technologies, is crucial for monitoring and controlling M/NPs pollution and developing sustainable solutions.

Preliminary study on the ejection of microplastics from different types of face masks

Face masks are strongly believed to be the best precaution to reduce the transmission of the SARS-CoV-2 virus, which resulted in an unprecedented surge in the production and use of personal respiratory protective equipment. Unfortunately, this surge led to improper disposal of used masks. This study aimed to assess the occurrence of microplastics (MPs) in used and unused surgical and cloth masks and N95 respirators. Respective samples were kept in a rotary shaker with distilled water in an Erlenmeyer flask for 5 hr to assess the release of MPs. Surgical masks showed a greater occurrence of microplastics release; an average of 18.27 items/mask were released from used and discarded surgical masks and 10.87 items/mask were released from unused new masks Fibers and fragments smaller than 0.5 mm in size were found to have a predominant presence in all the observed facemasks and respirators. The ATR-FTIR analysis of all the masks and respirators revealed the presence of four different polymers, namely polyethylene (PE) 46%, polypropylene (PP) 27%, polyamide (PA) 15% and polystyrene (PS) 12%. The microplastics released by face masks and N95 respirators can be carried by the environment or directly inhaled during use. As a result, using masks and N95 respirators repeatedly could expose individuals to microplastics. The proper use of face masks and N95 respirators and proper disposal practices should be maintained to prevent human and environmental exposures to MPs. MPs have been shown to affect individuals at the cellular to systems level, and additional research on the effects of MPs on human health is needed.

Mechanisms of microplastics on gastrointestinal injury and liver metabolism disorder (Review)

With the high production and use of plastic products, a large amount of microplastics (MPs) is generated by degradation, which causes environmental pollution. MPs are particles with a diameter <5 mm; further degradation of MPs produces nano‑plastics (NPs), which could further increase the damage to cells when entering the human body. Therefore, the present review summarizes the effect of MP and NP deposition on the human gastrointestinal tract and the underlying injury mechanism of oxidative stress, inflammation and apoptosis, as well as the potential mechanism of glucose and liver lipid metabolism disorder. The present review provides a theoretical basis for research on the mechanisms of MPs in gastrointestinal injury and liver metabolism disorder. Further studies are needed for prevention and treatment of gastrointestinal diseases caused by MPs and NPs.

Unveiling plastifoamcrete: Composition, characteristics, and environmental threats of urban plastic variants

As plastic pollution research advances, novel plastic forms continue to emerge, posing new challenges for pollution control and environmental management. While coastal plastic pollution has been widely studied, urban environments remain understudied. This study introduces plastifoamcrete, a newly identified variant of plasticoncrete found in urban waste in Mexico City. Plastifoamcrete refers to fragmented pieces of concrete containing embedded microplastic Styrofoam beads, formed from the breakdown of foamed concrete during demolition and improper disposal. We analyzed 12 samples, each exhibiting various shapes and sizes (ranging from 3.56 x 3.66 to 16.18 × 10.50 cm) and signs of pitting, possibly due to bead release during construction demolition or bead shaping during foamed concrete production. Bead distribution was uneven, with abundances ranging from 395 to 1938 cm2, and sizes between 0.46 and 5.8 mm. FTIR analysis confirmed their polystyrene composition. Given its friable nature, plastifoamcrete poses a risk of microplastic release and facilitates the transport of synthetic debris across terrestrial and aquatic environments. Its degradation not only can contribute to microplastic pollution but may also alter environmental pH, promote biofilm colonization, and serve as a vector for pollutant accumulation and dispersal, amplifying its ecological impact. By identifying plastifoamcrete within urban waste streams, this study broadens the scope of plastic pollution research and underscores the importance of integrating construction waste management into environmental policies.

Toxicity Mechanisms of Microplastic and Its Effects on Ruminant Production: A Review

Plastic pollution has become one of the major environmental problems facing human beings in the world today. Plastic waste accumulated in the environment forms plastic particles of different sizes due to farming activities, climate change, ultraviolet light, microbial degradation, and animal chewing. The pollution caused by microplastics has become a major environmental problem in recent years, and it is also a research hotspot in the field of ecological environment. More and more studies have found that ruminants are exposed to microplastics for a long time, which seriously threaten their healthy growth. This paper introduces the current situation of plastic pollution; the properties of microplastics and their effects on the ecological environment, human beings, and animals; summarizes the types and toxicity mechanisms of microplastics; and concludes the main ways that microplastics enter ruminants and their harm to them. In addition, the shortcomings and future development of microplastics in ruminants research are summarized and prospected to provide theoretical reference for the related research on alleviating the influence of microplastics on ruminant production.

Microplastics in municipal solid waste landfill leachate and their removal in treatment units: A perspective of controlled and uncontrolled landfills

Leachate produced from municipal solid waste landfill serves as a potential pathway for microplastics (MPs) release into the environment with a high potential for soil, surface water, and groundwater contamination. These MPs not only persist for longer duration of time in the landfill but also interact with toxic chemical contaminants. These interactions arise from the hydrophobic characteristics and minuscule size of MPs, which absorb a variety of emerging toxic contaminants present in these systems thereby amplifying the risk to surrounding environment. This study was performed to investigate the abundance, characteristics, and pollution risk of MPs in leachate from two contrasting landfill systems in the cities of Chandannagar and Baidyabati, India. A total of 8 leachate samples from an uncontrolled landfill (UCL), i.e., open dump, and 24 samples from different leachate treatment units (LTUs) of a controlled landfill (CL) were evaluated. Particle sizes of 1-5 mm (41.9%) in UCL and 0.025-0.5 mm (46.2%) in CL were predominant. Seven different types of polymers were identified in untreated leachate samples from UCL having concentration 53.4 ± 6.69 p/L (mean ± standard deviation) and in CL 34.7 ± 4.73 p/L. The predominant shapes were films, fragments, and fibers in UCL, whereas fragments and fibers dominated in CL. Polyethylene and polypropylene were the most frequent types of polymers observed in both sites. In CL, collection well, aeration lagoon, and sedimentation pond were used for LTUs, in which overall 83.3% MPs removal was achieved. High removal in LTUs highlights the importance of engineered systems for leachate management. However, optimization of these units is needed for enhanced removal of particles <0.5 mm. For UCL the findings suggest urgent need for implementing basic containment and treatment systems, particularly given their higher pollution risk indices. Varying landfill designs, waste compositions, and weather conditions of specific locations restrict generalisation of the findings to other regions. Therefore, long-term monitoring studies across different geographical and climatic conditions are recommended to develop more comprehensive management strategies.

Microplastics in our diet: A growing concern for human health

Microplastics (MPs), particles smaller than 5 mm, are widely distributed in the environment, raising concerns about their long-term human health impact. MPs can enter the human food chain through various sources, including drinking water, salt, plant-based derived products, animal-based derived products (especially seafood), alcoholic beverages, and packaged food. Once in the human body, MPs have been detected in various biological tissues and secretions, such as feces, blood, semen, breastmilk, thrombi, colon, atheroma, and liver, highlighting their capacity for bioaccumulation. The most commonly identified polymers include polyethylene (PE), polypropylene (PP), and polystyrene (PS), along with others such as polyethylene terephthalate (PET), polyvinyl chloride (PVC), and polymethyl methacrylate (PMMA). This review presents a perspective on underexplored food contamination by MPs, discussing the presence of these plastic fragments in human biological systems and discussing in vivo studies that investigate their potential health risks. Emerging evidence links MPs to inflammatory responses, oxidative stress, and cellular dysfunction, potentially contributing to gastrointestinal disorders, neurotoxicity, reproductive toxicity, and cardiovascular risks. Key knowledge gaps persist for understanding health impacts under environmental relevant conditions, particularly regarding long-term exposure, particle size effects, chemical composition, and interactions with environmental pollutants. Addressing these challenges requires the development of advanced experimental models and human-relevant tissue studies, to improve understanding of MPs bioaccumulation, toxicity, and mechanisms of action. This work underscores the urgency of mitigating MP exposure and advancing studies to better understand their real implications for human health.

Concise, Rapid, and Comprehensive Approach for Microplastic Detection Based on Ambient Microwave Plasma Torch Desorption/Ionization Mass Spectrometry

Microplastics (MPs) have been universally recognized as a pervasive and enduring environmental hazard, promoting research on relevant analytical techniques. Despite the unique advantages of mass spectrometry (MS) for polymer identification, lengthy procedures and complex data processing are always ineluctable. In this study, an ambient microwave plasma torch (MPT) ion source coupled with an LTQ Orbitrap MS was developed, presenting a rapid and concise analytical approach for MPs with simplified pretreatment and intuitive mass spectra. One testing process took approximately 30 s, enabling a higher efficiency of analysis. Furthermore, the method was not constrained by the MP size limitation; even macroscale polymer blocks could be detected. Under the optimized conditions, the method was proven to be efficient for the desorption and ionization of a wide range of MPs (polyamide, poly(ethylene terephthalate), polymethacrylate, polylactic acid, poly(3-hydroxybutyrate), polypropylene, and polythene), while the distinctly decipherable spectra intuitively reflected the mass intervals conforming to the corresponding monomer of MPs. Linear relationships were established between sample mass and the intensity of characteristic ion, with R2 exceeding 0.98. Additionally, a simplified pretreatment process in conjunction with MPT-MS was explored, verifying the method's resilience to matrix interferences and its applicability to environmental sample analysis. Furthermore, the compatibility of the established method with scanning electron microscopy was taken into consideration, thereby complementing traditional MS analysis by providing additional insights into the size and morphology of MPs. This study employed MPT as the ion source for MS detection of MPs, establishing a concise, rapid, and comprehensive method specifically targeting the analysis of MPs, which provided inspiration for the extraction and characterization of MPs in environmental samples.

Zebrafish and Drosophila as Model Systems for Studying the Impact of Microplastics and Nanoplastics ‐ A Systematic Review

Microplastics and nanoplastics (MNPs) are byproducts of plastics created to benefit humanity, but improper disposal and inadequate recycling have turned them into a global menace that we can no longer conceal. As they interact with all living organisms, including humans, their mechanism of interaction and their perilous impact must be meticulously investigated. To uncover the secrets of MNPs, there must be model systems that exist to interlink the two major scenarios: they must represent the environmental impact and be relevant to humans. Therefore, zebrafish and Drosophila are perfect to describe these two cases, as they are well studied and relatable to humans. In this review, 39% zebrafish studies reported higher mortality and hatching rates at greater MNP concentrations, severe oxidative stress as seen by raised malondialdehyde (MDA) levels, and reduced superoxide dismutase (SOD) activity. About 50% of studies showed severe neurotoxic behavior with drop of locomotor activity, suggesting neurotoxicity. MNPs have a significant impact on fertility rate of Drosophila. More than half of the studies revealed genotoxicity in Drosophila as observed by wing spot assays and modified genomic expressions associated with stress and detoxification processes. These findings emphasize the potential of MNPs to bioaccumulate, impair physiological systems, and cause oxidative and neurobehavioral damage. This study underscores the importance for thorough risk evaluations of MNPs and their environmental and health consequences.

Microplastic migration and transformation pathways and exposure health risks

Plastics play a crucial role in modern life, but improper use and disposal have resulted in microplastics becoming widespread in the environment, raising significant concerns about both the environment and human health. Extensive research has explored the transformation mechanisms, bioaccumulation, ecological impacts, and health risks associated with microplastics. The present review first analyzes the migration, transformation, and degradation pathways of microplastics on a global scale, and then synthesizes current knowledge on the types, sources, and migration pathways of microplastics in soil, atmosphere, and aquatic environments, emphasizing transformation mechanisms like photo-aging and microbial degradation, and detailing their ecological and human health impacts. Additionally, this review examines gaps in current research and identifies critical areas needing further study, such as key control points in microplastic degradation processes and the mechanisms underlying health risks to populations. The aim is to provide a comprehensive reference for advancing microplastic pollution control, ecological protection efforts, and health risk assessment frameworks.

Multi-omics association pattern between gut microbiota and host metabolism of a filter-feeding fish in situ exposed to microplastics

Microplastics (MPs) are widespread in water environments and can affect gut microbiota and host metabolism of fish, but whether changes in host metabolism under MPs are mediated by gut microbiota remains unclear. Here, silver carp, a filter-feeding fish with important ecological functions, was in-situ exposure to environmentally relevant MPs. Multi-omics analysis and fecal microbiota transplantation were used to reveal the metabolic responses of carp along gut-liver-muscle axis. After three months of in situ exposure to MPs, community structure of gut microbiota of carp was reshaped, and five dominate phyla were significantly changed, including increased Cyanobacteria, Chloroflexi and Planctomycetota but decreased Firmicutes and Fusobacteriota. Weighted gene co-expression network analysis was further performed between these phyla and liver transcription spectrum, showing that the hub gene module contained up-regulated hppD, maiA and plg and activated ubiquinone and other terpenoid-quinone biosynthesis and phenylalanine metabolism. By fecal microbiota transplantation, the key gene module associated with core microbiota phyla of carp was verified in germ-free zebrafish. Interestingly, up-regulated hppD, maiA and plg and enriched phenylalanine metabolism were also observed in this module. Subsequently, metabolome performed in carp liver also shared activated phenylalanine metabolism, including increased trans-cinnamic acid and L-tyrosine. Furthermore, high-associated mapping showed that the differentially expressed metabolites (gamma-aminobutyric acid, ornithine and L-serine) related to amino acid metabolism in carp muscle were significantly accompanied with increased L-tyrosine in its liver. Overall, MPs exposure could change gut microbiome of silver carp and alter host metabolism especially amino acid metabolism along the gut-liver-muscle axis.

Microplastics in Mussels (Mytilus galloprovincialis): Understanding Pollution in Italian Seas

Plastic marine litter is a critical issue that threatens marine ecosystems. This study investigated microplastics (MPs) contamination in the Italian seas, involving regions significantly affected by pollution from urban, industrial and agricultural sources. The research, conducted in collaborations between 10 different Experimental Zooprophylactic Institutes throughout Italy, analyzed Mytilus galloprovincialis (common mussels) for its filtration capacity and suitability as a bioindicator. Using data from two projects funded by the Italian Ministry of Health, MPs were detected from 7% to 13% of mussel samples, mainly polypropylene and polystyrene fragments and fibers. These findings align with previous studies highlighting the pervasive presence of MPs and their potential risks as mussels are consumed whole, allowing MPs to be ingested. The study underscores the need for standardized detection methods and coordinated policies to mitigate plastic pollution. Public awareness campaigns and improved waste management practices are key to addressing the environmental and health impacts of MPs. Further research on the long-term effects of MPs on marine ecosystems and human health is essential to developing comprehensive mitigation strategies.

Impact of plastic pollution on ecosystems: a review of adverse effects and sustainable solutions

The primary source of the growing concern regarding marine, aquatic, and land pollution is plastic products, the majority of which are made of synthetic or semi-synthetic organic compounds. These combinations include materials like coal and natural gas that are obtained through petrochemical processes. As these two types of plastic-derived products are produced and disposed of, they have a major impact on the ecosystems. According to recent figures, around 400 million tons of plastic and related products derived from plastic are produced annually, and it became double in the last two decades. Plastic pollutants are introduced into ecosystems by a variety of stakeholders at different points in their daily lives, whether intentionally or accidentally. They have become a major source of adverse effects, toxicity development in natural entities, and problems. The aquatic, marine, and land ecosystems are vital to human existence, which emphasizes how difficult it is to stop pollution from it. This review highlights the adverse impacts of plastics, plastic-based products, and micro-nanoplastics on aquatic, terrestrial, and marine ecosystems while addressing advances in biodegradable plastics, recycling innovations, plastic-degrading enzymes, and sustainable solutions to reduce environmental risks.

Genotoxic and cytotoxic effects of polystyrene nanoplastics on human lymphocytes: A comprehensive analysis

A growing amount of plastic waste is finding its way into natural ecosystems as a result of the widespread usage of plastics in modern society. These wastes degrade physically and biologically over time, transforming into microplastics (MPs) and nanoplastics (NPs). MPs and NPs emissions from the terrestrial environment then mix with rivers and eventually the seas, forming garbage. The cytotoxic and genotoxic effects of 50 nm polystyrene nanoplastics (PsNP) on human lymphocytes were assessed using the in vitro mitotic index (MI), micronucleus (MN), and comet assays. Both 24 and 48-h applications were performed for MI, and it was determined that 50 nm PsNP provided a statistically significant decrease in MI compared to the control at all concentrations and application times (except 0.001 and 0.1 μg/mL at 24 h). According to the MN test results, the MN frequency increased significantly at all concentrations when compared to the negative control. In the comet test, a statistically significant increase of comet tail length was observed at 0.001, 10 and 100 μg/mL concentration with 50 nm PsNP exposure. Tail moment also showed a statistically significant increase at the lowest concentration of 0.001 μg/mL and the highest concentration of 1, 10, 100 μg/mL compared to the negative control. All test results show that PsNP has both genotoxic and cytotoxic potential.

Environmental impact of microplastics and potential health hazards

Microscopic plastic (microplastic) pollutants threaten the earth's biodiversity and ecosystems. As a result of the progressive fragmentation of oversized plastic containers and products or manufacturing in small sizes, microplastics (particles of a diameter of 5 mm with no lower limit) are used in medicines, personal care products, and industry. The incidence of microplastics is found everywhere in the air, marine waters, land, and even food that humans and animals consume. One of the greatest concerns is the permanent damage that is created by plastic waste to our fragile ecosystem. The impossibility of the complete removal of all microplastic contamination from the oceans is one of the principal tasks of our governing body, research scientists, and individuals. Implementing the necessary measures to reduce the levels of plastic consumption is the only way to protect our environment. Cutting off the plastic flow is the key remedy to reducing waste and pollution, and such an approach could show immense significance. This review offers a comprehensive exploration of the various aspects of microplastics, encompassing their composition, types, properties, origins, health risks, and environmental impacts. Furthermore, it delves into strategies for comprehending the dynamics of microplastics within oceanic ecosystems, with a focus on averting their integration into every tier of the food chain.

NO-mediated DNA damage induced by polystyrene nanoparticles triggers program cell death in mesenchymal stem cells

Daily contact with considerable amounts of polystyrene nanoparticles (PSNPs) may cause harmful effects on the living organisms, through mechanisms that are not fully understood. The study aimed to evaluate the cytotoxic and genotoxic effects of PSNPs (size 200 nm and 40 nm) in mesenchymal stem cells (MSCs). In order to estimate cellular uptake and retention of nanoplastics, PSNP-treated cells have been analyzed by transmission electron microscopy. For assessing morphology and viability of MSCs after PSNP treatment at two environmentally relevant doses (0.47 and 4.7 μl/ml) for 24 hours, HE and Giemsa staining were performed. Annexin V‑FITC/PI assay was used to quantify PSNPs-mediated cell death. Genotoxicity of PSNPs was evaluated by Comet test. The capacity of PSNPs to trigger the production of free radicals in MSCs was also evaluated. TEM confirmed endocytosis of PSNPs. Decreased cell volume, nuclear hyperchromatism, edge aggregation, and formation of densely stained apoptotic bodies, indicated that PSNP-treated MSCs undergo apoptosis. The presented data showed that both concentration of PS particles significantly increased early apoptotic cell death in comparison to untreated cells. Moreover, both doses of PSNPs significantly increased the genetic damage index in MSCs in dose-dependent manner. In conclusion, PSNPs penetrate, accumulate and induce cytotoxic and genotoxic damage in MSCs.

The unseen perils of oral-care products generated micro/nanoplastics on human health

The extensive use of plastics in modern dentistry, including oral care products and dental materials, has raised significant concerns due to the increasing evidence of potential harm to human health and the environment caused by the unintentional release of microplastics (MPs) and nanoplastics (NPs). Particles from sources like toothpaste, toothbrushes, orthodontic implants, and denture materials are generated through mechanical friction, pH changes, and thermal fluctuations. These processes cause surface stress, weaken material integrity, and induce wear, posing health risks such as exposure to harmful monomers and additives, while contributing to environmental contamination. MPs/NPs released during dental procedures can be ingested, leading to immune suppression, tissue fibrosis, and systemic toxicities. The gut epithelium absorbs some particles, while others are excreted, entering ecosystems, accumulating through the food chain, and causing ecological damage. Although analytical techniques have advanced in detecting MPs/NPs in oral care products, more robust methods are needed to understand their release mechanisms. This review explores the prevalence of MPs/NPs in dentistry, the mechanisms by which MPs/NPs are released into the oral environment, and their implications for human and ecological health. It underscores the urgency of public awareness and sustainable dental practices to mitigate these risks and promote environmental well-being.

Crystallization of n-Alkanes under Anisotropic Nanoconfinement in Lipid Bilayers

Understanding crystallization behavior is integral to the design of pharmaceutical compounds for which the pharmacological properties depend on the crystal forms achieved. Very often, these crystals are based on hydrophobic molecules. One method for delivering crystal-forming hydrophobic drugs is by means of lipid nanoparticle carriers. However, so far, a characterization of the potential crystallization of fully hydrophobic molecules in a lipid environment has never been reported. In this work we investigate the crystallization behavior of two model hydrophobic chains, n-eicosane (C20) and n-triacontane (C30), in phospholipid bilayers. We combine static 2H nuclear magnetic resonance (NMR) spectroscopy and differential scanning calorimetry (DSC) and show that C30 molecules can indeed crystallize inside DMPC and POPC bilayers. The phase transition temperatures of C30 are slightly reduced inside DMPC, and rotator phase formation becomes a two-step process: Preorganized n-alkane chains assemble in rotator-phase crystallites just as fast as bulk C30, but further addition of molecules is notably slower. Under the same isothermal conditions, different crystal forms can be obtained by crystallization in the membrane and in bulk. In excess water conditions, homogeneous nucleation of C30 is observed. The initial anisotropic molecular arrangement of C30 molecules in the membrane is readily recovered upon reheating, showing reversibility. The shorter C20 molecules on the other hand become trapped in the DMPC membrane gel-phase upon cooling and do not crystallize. This work marks the first observation of the crystallization of hydrophobic chains inside a lipid bilayer environment. As such, it defines a fundamental starting point for studying the crystallization characteristics of various hydrophobic molecules in lipid membranes.

Toxicity assessment of DMSO extracts of environmental aged beached plastics using human cell lines

Plastic products contain complex mixtures of chemical compounds that are incorporated into polymers to improve material properties. Besides the intentional chemical additives, other compounds including residual monomers and non-intentionnaly added substances (NIAS) as well as sorbed pollutants are usually also present in aged plastic. Since most of these substances are only loosely bound to the polymer via non-covalently interactions, i.e., van der Waals forces, they may leach to the surrounding environment. Although there is increasing knowledge about toxicity of weathered plastic to aquatic organisms, only little is known about how plastic associated chemicals affect human health. Seafood consumption is one of the routes of human exposure to microplastics. The aim of this study was to evaluate the ability of naturally aged plastic associated chemicals to induce harmful effects to human health via the consumption of MP-contaminated seafood. Human colorectal adenocarcinoma Caco-2 and human hepatocyte carcinoma HepG2 cells were selected as model of the colon and liver cells respectively. They are known for their high capacity to metabolize organic contaminants. Both cell lines were exposed to DMSO extracts of different plastics to investigate the effects of chemicals on cell viability, oxidative stress induction and genotoxicity. In addition, the estrogenic effects of DMSO-extracts were evaluated using an estrogen-dependent reporter gene assay in T47D-Kbluc human breast cancer cells. Chemical profiles of the DMSO extracts were polymer-dependent, with polyvinyl chloride (PVC) highly contaminated with metals while polypropylene (PP) contained the lowest concentration of metals. Organic pollutants, including polycyclic aromatic hydrocarbons, were mainly found in PVC, high density polyethylene (HDPE) and PP extracts, whereas other extracted plastics had less (PP) to no organic contamination (polyethylene terephthalate PET). PVC was the most toxic plastic inducing cytotoxicity for both cell lines. DNA damage was observed for Caco-2 cells exposure to HDPE, PVC and nylon. Reactive oxygen species were induced only with nylon extracts in intestinal cells. No toxicity was observed for PP and PET and none of the tested plastics had any estrogenic effect. Our results demonstrate that some environmental aged plastic material released a variety of known and unknown chemical compounds some of which are toxic in vitro and contribute to the knowledge on adverse human health effects of plastics.

Microplastics in different nasal irrigation options

PURPOSE

We aimed to assess the presence of microplastics in nasal irrigation methods commonly used in the treatment of sinusitis and rhinitis, and to evaluate human exposure.

METHODS

A total of 150 samples were included in the study, consisting of nasal wash bottles containing nasal irrigation solution, seawater spray, syringes for nasal irrigation with isotonic solution. The amount of microplastics per millilitre in the samples and patient exposure during single use were assessed separately for each method and product. All samples were filtered using a stainless steel vacuum filter on filter paper with a pore size of 1.2 μm, washed at least three times with distilled water and incubated at 45 °C for 24 h to prevent mould growth. Identification and counting of microplastics was performed using a Leica Flexacam C1 camera connected to an M80 stereomicroscope. The presence of microplastics was confirmed by the hot needle method and Nile red staining.

RESULTS

An average of 6.49 ± 13.08 microplastics/product was detected in all filtered samples. The lowest microplastic count was 0 microplastics/product in syringes and the highest was 92 microplastics/product in nasal wash bottles. Significant differences in the amount of microplastics individuals were exposed to during a single use were found between nasal wash bottles and seawater brands, while no significant differences were found between syringe brands. When nasal wash kits, seawater sprays and isotonic nasal rinses were evaluated separately, significant differences were found in the number of microplastics, the microplastics/ml ratio and the number of microplastics exposed during a single use. The highest microplastic exposure was found in nasal irrigation bottles.

CONCLUSION

The exposure of individuals to microplastics increases with medical support treatments, regardless of intranasal or intravenous administration. Due to the inflammation, oxidative stress and proliferation caused by microplastics, new regulations and inspections of production conditions should be implemented worldwide to reduce exposure.

Combined toxic effects of polystyrene microplastic and benzophenone-4 on the bioaccumulation, feeding, growth, and reproduction of Daphniamagna

The potential toxicity of microplastics (MPs) and UV filter Benzophenone-4 (BP4) to aquatic organisms has caused widespread concern among the public. However, the combined effects of MPs and BP4 on aquatic organisms are not well understood. This study sought to examine the combined impacts of 10 μg/L BP4, 1 mg/L Polystyrene (PS, 10 μm), and a mixture of both on the feeding, behavior, growth, and reproduction of Daphnia magna (D. magna) over a period of 21 days. The results showed that the combined exposure led to a reciprocal facilitation of bioaccumulation, along with a decrease in the second antenna beats frequency in D. magna. While the co-exposure did not change the body size or growth rate of D. magna, it did affect their feeding efficiency, leading to a decrease in Chlorella ingestion within a 24-h period. Furthermore, there was a high occurrence of malformations in two generations of D. magna exposed to BP4 and PS. The combined exposure also negatively affected reproductive parameters, such as the cumulative number of neonates and the days of first brood, suggesting a decline in overall reproductive success possibly due to feeding inhibition, with available energy potentially being redistributed between reproduction and growth in the daphnids. Co-exposure to BP4 and PS also led to elevated levels of Reactive Oxygen Species (ROS), Malonydialdehyde (MDA), and Glutathione (GSH) levels, as well as mRNA levels related to reproduction, growth, and detoxification in D. magna. Overall, this study delved into the consequences of BP4 and PS on bioaccumulation, feeding, behavior, growth, and reproduction, demonstrating that simultaneous exposure to BP4 and PS could pose a synergistic ecological hazard, potentially threatening aquatic organisms. These findings are critical and should be taken into account for accurate environmental risk assessments.

Polyethylene microplastics affect behavioural, oxidative stress, and molecular responses in the Drosophila model

The escalating presence of microplastic pollution poses a significant environmental threat, with far-reaching implications for both ecosystems and human health. This study investigated the toxicological impact of polyethylene microplastics (PE MPs) using Drosophila melanogaster, fruit flies, as a model organism. Drosophila were exposed to PE MPs orally at concentrations of 1 mg ml-1 and 10 mg ml-1 agar food. The study assessed behavioural parameters and biochemical markers including reactive oxygen species (ROS), superoxide dismutase (SOD), and glutathione-S-transferase (GST) activity. The expression levels of key genes (Hsp70Bc, rpr, and p53) were also analysed using the RT-qPCR technique. Results indicated a significant decline in climbing activity among adult flies and crawling behaviour in larvae, indicating potential disruption of motor function. Biochemical analysis revealed elevated ROS levels, indicative of oxidative stress, in both larval and fly stages. Moreover, the antioxidant defence system exhibited decreased SOD activity and a concentration-dependent increase in GST activity indicating the functioning of a quick xenobiotic clearance mechanism. Gene expression analysis demonstrated upregulation of rpr, p53, and Hsp70Bc genes, suggesting activation of cell death pathways and stress response mechanisms. Overall, these findings underline the adverse effects of PE MPs on Drosophila, including behavioural impairment, oxidative stress, and activation of stress response pathways.

Toxicity of parental co-exposure of microplastic and bisphenol compounds on adult zebrafish: Multi-omics investigations on offspring

In recent years, the widespread use of bisphenol compounds and microplastics (MP) have attracted attention due to their harmful effects. Here, individual and combined effects of MP and bisphenol compounds, were assessed on adult zebrafish after co-exposure of bisphenol A (BPA) or bisphenol S (BPS) and 25 μm polyethylene MP. Impacts on their offspring (the F1 generation) were also investigated. The reproductive toxicity in adult zebrafish impacted exerted by bisphenol compounds were aggravated by the co-presence of MP. Transcriptomics and metabolomics further showed single or co-exposure of bisphenol compounds and MP could together regulate apoptosis, calcium signaling pathway and glycerophospholipid signaling pathways. Our results also showed the different toxicity mechanisms on transcriptional and metabolic profiles in the combination effects of bisphenol compounds and MP. The co-exposure of BPA and MP predominantly influenced neurotoxicity via the MAPK signaling pathway and voltage-dependent calcium channels, whereas the co-exposure of BPS and MP principally affected visual development through phototransduction and retinol metabolism. The co-exposure of BPA and MP, as well as BPS and MP, specifically regulate lipid metabolism and carbohydrate metabolism in zebrafish offspring, respectively. Overall, this study provided a deep understanding of the toxicity differences between co-exposure and single exposure of bisphenol compound and MP in zebrafish, as well as the transgenerational effects and potential molecular mechanisms of bisphenol compounds and MP in zebrafish offspring.

Toxicity of microplastic fibers containing azobenzene disperse dyes to human lung epithelial cells cultured at an air-liquid interface

There is growing concern surrounding the human health effects following inhalation exposure to microplastic fibers (MPFs). MPFs can harbor chemical additives, such as azobenzene disperse dyes (ADDs), that may contribute to their toxicity. The goal of this study was to determine the acute biological effects of dyed polyethylene terephthalate MPFs to fully differentiated normal human bronchial epithelial (NHBE) cells cultured at an air-liquid interface. Cells were exposed to 2000 undyed MPFs (84.80 µg/cm2) or 2000 dyed MPFs (129.86 µg/cm2) colored with a black dye stuff containing the dye Disperse Violet 93 (DV93) using a mesh hopper delivery device. Cells were also exposed to DV93 only (1 µg/mL). Results show that the dyed MPFs caused a more pronounced decrease in cell viability and transepithelial electrical resistance compared to undyed MPFs and unexposed control cells. Additionally, the DV93 and dyed MPFs significantly upregulated the mRNA expression of CYP1A1 and CYP1B1, which was not observed in the undyed MPF group. These results support the idea that components of MPFs, specifically azobenzene disperse dyes, can leach from MPFs in biological systems and exert unique toxicity profiles. This study emphasizes the importance of considering toxicity associated with both the fibers themselves and chemical leachates in future studies.

Nanoplastic release from disposable plastics: Correlation with maximum service temperature

The potential for bioaccumulation of nanoplastics (NPs, <1 µm) increases as the particle size decreases. Since several disposable plastic products used daily may release NPs, their intake may be unavoidable. Therefore, it is crucial to examine the release patterns of NPs from these products. This study investigates the relationship between NP release and the Maximum Service Temperature (MST) of five plastic types, confirming the correlation under real-world conditions. The releasing tendencies of NPs were investigated using plastic pellets. We simulated the packaging of hot food in plastic containers, considering the physical dynamics of food delivery, and replicated cooking in an oven and microwave. We observed that the mass of NPs released tended to reach its maximum at the material's MST. In real-life conditions, the release of NP was found to increase with higher container content temperatures and longer packaging or cooking durations. Physical impacts were confirmed to be the most significant contributors to NP release. Moreover, Higher microwave power levels lead to greater NP release, with polar materials releasing more NPs compared to non-polar materials. Consequently, to minimize NP ingestion, it is recommended to use containers made from non-polar materials with a high MST.

Modeling the differential functional responses and selectivity of a marine copepod to nano/microplastics in mixture

Nano- and microplastics (NMPs) pollution is widespread in the oceans, posing potential risks to marine species. This study examined the accumulation capacity and selectivity potentials of NMPs by a marine copepod Parvocalanus crassirostris under different food mixtures by modeling the combined biokinetic and functional response. We investigated two sizes of NMPs (200 nm and 5 µm) across a concentration gradient (0 - 5000 µg/L) and varying diatom abundances (0, 104, 105 cells/mL). Fluorescence imaging and quantification revealed that P. crassirostris actively ingested NMPs at low concentration. Accumulation increased with NMPs concentration but eventually saturated due to gut capacity limits, following a Holling type II functional response (i.e., hyperbolic curve). Our novel functional response model estimated the key parameters and demonstrated that the maximum accumulation reached 5.3 % of dry weight with averaged half-saturation constants of 229 µg/L. The size of NMPs did not significantly affect the total accumulation or satiety levels. The presence of diatoms influenced the feeding selectivity and decreased the microplastic accumulation by 73 % at 105 cells/mL, while facilitating nanoplastic accumulation by 81 % at 104 cells/mL. This study enhanced our understanding of NMPs bioavailability and environmental fate in marine ecosystems.

Exposure to Polypropylene Microplastics Causes Cardiomyocyte Apoptosis Through Oxidative Stress and Activation of the MAPK-Nrf2 Signaling Pathway

Microplastics are a growing concern as pollutants that impact both public health and the environment. However, the toxic effects of polypropylene microplastics (PP-MPs) are not well understood. This study aimed to investigate the effects of PP-MPs on cardiotoxicity and its underlying mechanisms. The cardiotoxicity of exposure to different amounts of PP-MPs were investigated in both ICR mice and H9C2 cells. Our results demonstrated that sub-chronic exposure to 5 and 50 mg/L PP-MPs led to myocardial structural damage, apoptosis, and fibrosis in mice cardiomyocytes. Flow cytometry analysis revealed that PP-MPs could decrease mitochondrial membrane potential and induce apoptosis in H9C2 cells. Western blotting revealed decreased expression of Bcl-2, poly(ADP-ribose) polymerase (PARP) and caspase 3 and increased expression of Bax, cleaved-PARP, and cleaved-caspase 3 in PP-MPs-treated cardiac tissue and H9C2 cells. These results confirmed the apoptotic effects induced by PP-MPs. Moreover, PP-MPs treatment triggered oxidative stress, as evidenced by the increased levels of malondialdehyde; reduction in glutathione peroxidase, superoxide dismutase, and catalase activities in mice cardiac tissues; and increased reactive oxygen species levels in H9C2 cells. Finally, western blotting demonstrated that exposure to PP-MPs significantly reduced the expression levels of Nrf2 and p-ERK proteins associated with MAPK-Nrf2 pathway in both cardiac tissue and H9C2 cells. Overall, our findings indicate that PP-MPs can induce cardiomyocyte apoptosis through MAPK-Nrf2 signaling pathway, which is triggered by oxidative stress. This study provides a foundation for determining the effects of PP-MPs on cardiotoxicity and their underlying mechanisms.

Impacts of polystyrene nanoplastics on microgel formation from effluent organic matter

Municipal effluents discharged from wastewater treatment plants (WWTPs) are considered major contributors of nanoplastics (NPs) and dissolved effluent organic matter (dEfOM) to environments. Due to their small sizes, NPs can travel easily in waterways and evade wastewater treatment processes, and may directly interact with dEfOM, altering their environmental fates. However, although much research has examined the impact of natural organic matter on NPs, the interactions between NPs and dEfOM remain unexplored. This study investigated the influences of NPs on the behavior and capacity of dEfOM aggregation and surface granularity, and identified the possible aggregation mechanism. We also adjusted the salinity of water samples to simulate scenarios based on WWTP-sea continuums. Our data suggest that dEfOM can self-assemble with 55 nm polystyrene NPs to form microgels, particularly under high salinity conditions. NPs accelerates the formation speed and number of dEfOM aggregates, but the sizes of the aggregates remain largely unchanged. The relative particle counts at a salinity of 34 psu increased by 300 % compared to the control group. The potential mechanism behind NPs-microgels aggregation is likely driven by the synergistic effect of the divalent ion crosslinking and hydrophobic interactions between EfOM and NPs. Notably, NPs incorporation into microgels decreases the surface granularity, thereby possibly affecting settling velocity and colonization of aggregates, as well as microbial attachment and community diversity. Overall, our findings demonstrate the potential influence of NPs on dEfOM assembly and surface properties following effluent discharge, and can inspire further relevant studies on microorganism interactions, removal technologies, and the environmental transport of NPs.

Existence and fate of microplastics in terrestrial environment: A global fretfulness and abatement strategies

Widespread use of plastics in consumer products, packaging, cosmetics, and industrial and agricultural production has resulted in the ubiquitous occurrence of microplastics in terrestrial environment. Compared to the marine environment, only limited studies have investigated the microplastics pollution and associated risk in terrestrial environment. The present review summarizes the global distribution of microplastics in terrestrial environment, their transport pathways and fate, risk to ecosystem and human health, and abatement strategies. Small particle sizes (<500 μm); fragment, fiber, and film shapes; transparent and white color; polyethylene (PE), polypropylene (PP), and polyethylene terephthalate (PET) polymers were the major characteristics of the microplastics found in terrestrial environment. Microplastics in soils negatively affect soil organisms, while the impact of microplastics in terrestrial environment on human health is poorly understood, which needs to be explored further as there is clear evidence on their presence in human bodies. The removal of microplastics from soil environment is quite complex and costly, thus prevention of their releases is preferable. Among the existing abatement options, biodegradation, which harnesses bacterial strains to degrade microplastics through enzymatic hydrolysis, hold promise for terrestrial environment. Strengthening global cooperation, implementing timely policies on plastic use and recycle, and developing new technologies for control of microplastics are recommended to reduce the pollution in terrestrial environment. Global effort on reducing plastic wastes and enhancing their management is imperative, while substitution with biodegradable plastics could help minimize future accumulation of microplastics in terrestrial environment.

Sorption of trace metals by macro- and microplastics within intertidal sediments: Insights from a long-term field study within Burrard Inlet, British Columbia, Canada

Plastics are now the dominant fraction of anthropogenic marine debris and as a result of their long residence times, it is important to determine the threats that plastics present to marine ecosystems including their ability to sorb a diversity of environmental pollutants such as trace metals. To address this knowledge gap, this study examined the sorption of cadmium (Cd), copper (Cu), mercury (Hg), lead (Pb), and zinc (Zn) by macro- and microplastics of polyethylene terephthalate (PETE) and high-density polyethylene (HDPE) within marine intertidal sediments in a human-impacted area of Burrard Inlet (British Columbia, Canada). Trace metal sorption by macro- and microplastics was dependent on 1) polymer characteristics, notably the aging of the plastic over the duration of the field experiment as shown by the formation of new peaks via FTIR spectra; and 2) amounts of sediment organic matter, where the sorption of trace metals by the plastic particles decreased with increasing organic matter content (from 2.8 % to 15.8 %). Plastic particles play a minor role in trace metals sorption in the presence of organic matter at high concentrations as a result of competitive adsorption. Overall, the interaction of trace metals with sediment plastics was highly dynamic and to understand the key processes controlling this dynamic requires further study. This work contributed to our understanding on metal-plastic interactions in coastal intertidal sediments from urban environments and serve to support plastic pollution risk management and bioremediation studies.

Nano-Selenium Modulates NF-κB/NLRP3 Pathway and Mitochondrial Dynamics to Attenuate Microplastic-Induced Liver Injury

BACKGROUND

Microplastics (PS-MPs) are a new type of pollutant with definite hepatotoxicity. Selenium, on the other hand, has natural, protective effects on the liver.

OBJECTIVES/METHODS

The purpose of this experiment is to find out whether nano-selenium (SeNP) can alleviate liver damage caused by microplastics. Initially, we established through in vitro experiments that SeNP has the ability to enhance the growth of healthy mouse liver cells, while microplastics exhibit a harmful impact on normal mouse hepatocyte cell suspensions, leading to a decrease in cell count. Subsequently, through in vivo experiments on male ICR mice, we ascertained that SeNPs alleviated the detrimental impacts of PS-MPs on mouse liver.

RESULTS

SeNPs hinder the signaling pathway of NF-κB/NLRP3 inflammatory vesicles, which is crucial for reducing inflammation induced by PS-MPs. In terms of their mechanism, SeNPs hinder the abnormalities in mitochondrial fission, biogenesis, and fusion caused by PS-MPs and additionally enhance mitochondrial respiration. This enhancement is crucial in averting disorders in energy metabolism and inflammation.

CONCLUSIONS

To summarize, the use of SeNPs hindered inflammation by regulating mitochondrial dynamics, thus relieving liver damage caused by PS-MPs in mice. The anticipated outcomes offer new research directions that can be referenced in terms of inflammatory injuries caused by PS-MPs.

Polystyrene microplastics cause reproductive toxicity in male mice

Microplastics are a common environmental pollutant that disrupts the reproductive system of living organisms. We investigated the reproductive toxicity of 2 μm polystyrene microplastics (PS-MPs) in mice and treated them with PS-MPs for 6 weeks. We demonstrated that PS-MPs decreased the gonadosomatic index and the serum concentration of pituitary-testicular axis hormones (Follicle-stimulating hormone, Luteinizing hormone, and testosterone). The PS-MPs treatment also reduced viable epididymal sperm number and sperm motility. Our results also demonstrated a marked decrease in tubular differentiation index, spermatogenesis index, repopulation index, and steroidogenic foci. The PS-MPs treated mice demonstrated marketed tissue damage in the testis. We also found that reproductive abnormality in PS-MPs treated mice accompanied by reduced antioxidant capacity elevated oxidative stress, and, elevated apoptotic signaling. It was observed that Endoplasmic reticulum (ER) stress markers, including GRP78 and Chop, were upregulated. Based on these findings, oxidative stress and endoplasmic reticulum stress may contribute to the decline in the steroidogenic function of Leydig cells with PS-MPs treated.

Polystyrene nano-plastics impede skeletal muscle development and induce lipid accumulation via the PPARγ/LXRβ pathway in vivo and in vitro in mice

Nano-plastics (NPs) have emerged as a significant environmental pollutant, widely existing in water environment, and pose a serious threat to health and safety with the intake of animals. Skeletal muscle, a vital organ for complex life activities and functional demands, has received limited attention regarding the effects of NPs. In this study, the effects of polystyrene NPs (PS-NPs) on skeletal muscle development were studied by oral administration of different sizes (1 mg/kg) of PS-NPs in mice. The findings revealed that PS-NPs resulted in skeletal muscle damage and significantly hindered muscle differentiation, exhibiting an inverse correlation with PS-NPs particle size. Morphological analysis demonstrated PS-NPs caused partial disruption of muscle fibers, increased spacing between fibers, and lipid accumulation. RT-qPCR and western blots analyses indicated that PS-NPs exposure downregulated the expression of myogenic differentiation-related factors (Myod, Myog and Myh2), activated PPARγ/LXRβ pathway, and upregulated the expressions of lipid differentiation-related factors (SREBP1C, SCD-1, FAS, ACC1, CD36/FAT, ADIPOQ, C/EBPα and UCP-1). In vitro experiments, C2C12 cells were used to confirm cellular penetration of PS-NPs (0, 100, 200, 400 μg/mL) through cell membranes along with activation of PPARγ expression. Furthermore, to verify LXRβ as a key signaling molecule, silencing RNA transfection experiments were conducted, resulting in no increase in the expressions of PPARγ, LXRβ, SREBP1C, FAS, CD36/FAT, ADIPOQ, C/EBPα and UCP-1 even after exposure to PS-NPs. However, the expressions of SCD-1and ACC1 remained unaffected. The present study evidenced that exposure to PS-NPs induced lipid accumulation via the PPARγ/LXRβ pathway thereby influencing skeletal muscle development.

Microplastics in the Human Body: Exposure, Detection, and Risk of Carcinogenesis: A State-of-the-Art Review

Background: Humans cannot avoid plastic exposure due to its ubiquitous presence in the natural environment. The waste generated is poorly biodegradable and exists in the form of MPs, which can enter the human body primarily through the digestive tract, respiratory tract, or damaged skin and accumulate in various tissues by crossing biological membrane barriers. There is an increasing amount of research on the health effects of MPs. Most literature reports focus on the impact of plastics on the respiratory, digestive, reproductive, hormonal, nervous, and immune systems, as well as the metabolic effects of MPs accumulation leading to epidemics of obesity, diabetes, hypertension, and non-alcoholic fatty liver disease. MPs, as xenobiotics, undergo ADMET processes in the body, i.e., absorption, distribution, metabolism, and excretion, which are not fully understood. Of particular concern are the carcinogenic chemicals added to plastics during manufacturing or adsorbed from the environment, such as chlorinated paraffins, phthalates, phenols, and bisphenols, which can be released when absorbed by the body. The continuous increase in NMP exposure has accelerated during the SARS-CoV-2 pandemic when there was a need to use single-use plastic products in daily life. Therefore, there is an urgent need to diagnose problems related to the health effects of MP exposure and detection. Methods: We collected eligible publications mainly from PubMed published between 2017 and 2024. Results: In this review, we summarize the current knowledge on potential sources and routes of exposure, translocation pathways, identification methods, and carcinogenic potential confirmed by in vitro and in vivo studies. Additionally, we discuss the limitations of studies such as contamination during sample preparation and instrumental limitations constraints affecting imaging quality and MPs detection sensitivity. Conclusions: The assessment of MP content in samples should be performed according to the appropriate procedure and analytical technique to ensure Quality and Control (QA/QC). It was confirmed that MPs can be absorbed and accumulated in distant tissues, leading to an inflammatory response and initiation of signaling pathways responsible for malignant transformation.

Characterization of microplastics in soil, leachate and groundwater at a municipal landfill in Rayong Province, Thailand

Recent years have witnessed a dramatic increase in global plastic production, leading to heightened concerns over microplastics (MPs) contamination as a significant environmental challenge. MP particles are ubiquitously distributed across both continental and marine ecosystems. Given the paucity of research on MPs in Thailand, particularly regarding MPs contamination in terrestrial environments, this study focused on investigating the distribution and characteristics of MPs in a landfill area. We collected 15 soil samples, 2 leachate samples, and 7 groundwater samples from both inside and outside a municipal landfill situated in the urbanized coastal region of Rayong Province. Our findings revealed variability in MPs concentration across different sample types. In soil, the MP count ranged from 240 to 26,100 pieces per kg of dry soil, 58.71 % of all sample sizes are lower than 0.5 mm. Similarly, the size found in the leachate sample, and the average MP in the leachate samples was 139 pieces per liter of MPs. The groundwater samples showed a fluctuation in MPs count from 18 to 94 pieces per liter, and the size of MPs ranged mostly from 0.5 to 1 mm. The predominant forms of MPs identified were sheets, followed by fragments, fibers, and granules. According to μ-FTIR analysis, the majority of the MPs were composed of polyethylene and polypropylene, commonly used in plastic packaging and ropes. The observed high concentrations and extensive distribution of MP contamination underscore the urgency for further studies and effective management strategies to mitigate the adverse impacts of this pollution on various organisms and ecosystems.

Microplastics from petroleum-based plastics and their effects: A systematic literature review and science mapping of global bioplastics production

The use of bioplastics is a new strategy for reducing microplastic (MP) waste caused by petroleum-based plastics. This problem has received increased attention worldwide, leading to the development of large-scale bioplastic plants. The large amount of MPs in aquatic and terrestrial environments and the atmosphere has raised global concern. This article delves into the profound environmental impact of the increasing use of petroleum-based plastics, which contribute significantly to plastic waste and, as a consequence, to the increase in MPs. We conducted a comprehensive analysis to identify countries that are at the forefront of efforts to produce bioplastics to reduce MP pollution. In this article, we explain the development, degradation processes, and research trends of bioplastics derived from biological materials such as starch, chitin, chitosan, and polylactic acid (PLA). The findings pinpoint the top 10 countries demonstrating a strong commitment to reducing MP pollution through bioplastics. These nations included the United States, China, Spain, Canada, Italy, India, the United Kingdom, Malaysia, Belgium, and the Netherlands. This study underscores the technical and economic obstacles to large-scale bioplastic production. Integr Environ Assess Manag 2024;20:1892-1911. © 2024 SETAC.

Micro(nano)plastic and Related Chemicals: Emerging Contaminants in Environment, Food and Health Impacts

Microplastic pollution is a problem of increasing concern in food, and while food safety issues around the world are serious, an increasing number of food safety issues related to microplastics have become the focus of people's attention. The presence of microplastics in food is a worldwide problem, and they are present in all kinds of foods, foods of both animal and plant origin, food additives, drinks, plastic food packaging, and agricultural practices. This can cause problems for both humans and the environment. Microplastics have already been detected in human blood, heart, placenta, and breastmilk, but their effects in humans are not well understood. Studies with mammals and human cells or organoids have given perspective about the potential impact of micro(nano)plastics on human health, which affect the lungs, kidneys, heart, neurological system, and DNA. Additionally, as plastics often contain additives or other substances, the potentially harmful effects of exposure to these substances must also be carefully studied before any conclusions can be drawn. The study of microplastics is very complex as there are many factors to account for, such as differences in particle sizes, constituents, shapes, additives, contaminants, concentrations, etc. This review summarizes the more recent research on the presence of microplastic and other plastic-related chemical pollutants in food and their potential impacts on human health.

Microplastics in the soil-water-food nexus: Inclusive insight into global research findings

Nuisance imposed by biotic and abiotic stressors on diverse agroecosystems remains an area of focus for the scientific fraternity. However, emerging contaminants such as microplastics (MP) have imposed additional dimension (alone or in combinations with other stressors) in agroecosystems and keep escalating the challenges to achieve sustainability. MP are recognized as persistent anthropogenic contaminants, fetch global attention due to their unique chemical features that keeps themselves unresponsive to the decaying process. This review has been theorized to assess the current research trends (along with possible gap areas), widespread use of MP, enhancement of the harshness of heavy metals (HMs), complex interactions with physico-chemical constituents of arable soil, accumulation in the edible parts of field crops, dairy products, and other sources to penetrate the food web. So far, the available review articles are oriented to a certain aspect of MP and lack a totality when considered from in soil-water-food perspective. In short, a comprehensive perspective of the adverse effects of MP on human health has been assessed. Moreover, an agro-techno-socio-health prospective-oriented critical assessment of policies and remedial measures linked with MP has provided an extra edge over other similar articles in influential future courses of research.