Human health concerns regarding microplastics in the aquatic environment - From marine to food systems

Exploring the toxicology, socio-ecological impacts and biodegradation of microplastics in Africa: Potentials for resource conservation

Achieving upcycling and circularity in the microplastic economy predominantly depends on collecting and sorting plastic waste from the source to the end-user for resource conservation. Microplastics, whether from packaging or non-packaging materials, pose a significant environmental challenge as they are often not prioritized for collection or recycling initiatives. The presence of additives impedes the quality of plastic recyclates and the persistence of microplastics as shredded resultants remain a threat to the aquatic and terrestrial ecosystem and its biodiversity. Despite the increasing global research on microplastics, the success of plastic and microplastic waste management in Africa is yet to be fully attained. Considering the improper disposal, limited recycling and upcycling intervention, lack of policy, and strict laws against plastic waste management defaulters, the ecosystems in Africa remain immensely impacted by several socio-ecological factors leading to the loss of aquatic organisms through reducing fertility and increasing stress. As a ripple consequence, the disruption of economic activities, toxic effects on animal/human health, and climate crisis are among their impact. This review therefore provides comprehensive detail of microplastic production and challenges in Africa, the toxicology concerns, socio-ecological issues associated with microplastic waste management, and insight into approaches to mitigate plastic pollution through recycling, upcycling, bioprocessing and their biodegradation with social insects and microorganisms which may form the basis for adoption by policymakers and researchers, thereby minimizing the consequences of plastic pollution in Africa.

Microplastic contamination in threatened wild felids of India: Understanding environmental uptake, feeding implications, and associated risks

While the presence of microplastics (MPs, <5 mm) in various aquatic organisms is well-documented, studies on the accumulation of MPs in terrestrial predators remain limited worldwide, including in India. This study aims to evaluate, for the first time, the occurrence of MPs in the scat of mid-sized felids-fishing cat and jungle cat-from their overlapping habitat in the Gangetic Estuary of India. The risk assessment of MPs and management recommendation for MP mitigation was also discussed in this context. Notably, our study is the first to report the presence of MPs and mesoplastics in fishing cat from India and jungle cat globally. The abundance of MPs was found to be higher in jungle cat (12.6 ± 1.93 MP/g d.w) compared to fishing cat (10.5 ± 2.12 MP/g d.w) in the Gangetic estuary. Furthermore, fiber-shaped (70.37%) and 1-5 mm-sized (47.73%) MPs predominated in both felid species, while fiber bundles were observed only in jungle cat. Red-colored MPs (27.62%) were predominantly found in fishing cat, whereas transparent MPs (33.33%) were more common in jungle cat. Scanning electron microscopy revealed possible environmental and digestive degradation marks on the MPs. A total of seven synthetic and one natural polymer were identified, with Ethylene Vinyl Alcohol (55.56%) being predominant in fishing cat and Polyethylene (33.33%) more common in jungle cat. Polymer risk assessment indicated that the MPs in fishing cat fall into the danger category, Group IV (PHI 100-1000), while jungle cat possess high threat under extreme danger category, Group V (PHI >1000). The observed MPs and mesoplastics in felids probably come from adjacent environmental uptake and/or accumulate through trophic transfer from prey items. The evidence of MPs in felids may pose a threat to the big cat-Royal Bengal tigers in the Sundarbans. Therefore, various landscape-based policy implementations are recommended to mitigate MP pollution.

The spatio-temporal variability of soil microplastic distribution and erosion-induced microplastic export under extreme rainfall event using sediment fingerprinting and 7Be in intensive agricultural catchment

Intensive agricultural production and land management often lead to soil microplastics (MPs) accumulation and aggravated erosion consequently polluting water bodies. However, little is known about the occurrence and migration of soil MPs induced by soil erosion at the catchment scale. This study firstly reported the spatio-temporal variability in soil MPs distribution, and erosion-induced microplastic export loads under extreme rainfall events in an intensive agricultural catchment. The results indicated that microplastic abundance peaked in November 2022 and varied by land use types, among which cropland converted from forest (C(F)) and crop farmland (C) had the highest abundance, vegetable farmland (V) had the lowest abundance on average. Most MPs were < 500 μm and the primary polymers were polyamide (PA), polypropylene (PP) and polyethylene (PE). Sediment contribution and microplastic export loads were identified using compound specific stable isotope and Berillium-7 under an extreme rainfall event. F and C(F) were merged because their δ13C values were non-distinguishable and were identified as the primary sediment source (50.14 ± 0.27 %), contributing most to microplastic export loads due to land management policy shifting. Changed land uses should be the main focus for catchment erosion control and microplastic pollution prevention in intensive agriculture in China and elsewhere.

Ecological risk assessment and ingestion of microplastics in edible finfish and shellfish species collected from tropical mangrove forest, Southeastern India

In the Pichavaram mangroves in Southeast India, this study examines the seasonal trends and consumption of microplastic (MPs) by several fish and shellfish species. Four different seasons viz. summer, pre-monsoon, monsoon, and post-monsoon were used to gather the fish and shellfish samples from Pichavaram Mangrove Forest. The results of the present investigation revealed that MP abundance was higher during the monsoon (45 %), suggesting seasonal runoff and increased plastic pollution during heavy rains as key contributors. We observed microplastics in Liza tade (mullet), with 13.33 MPs/individuals in the summer, 0.77 MPs/individuals in the pre-monsoon, 6.3 MPs/individuals in the monsoon, and 2.67 MPs/individuals in the post-monsoon. A significant proportion (32 %) of MPs were smaller than 1 mm. The fibres were predominated with blue (40 %) and red (13 %). The polyethylene (PE), polypropylene (PP), and polyethylene terephthalate (PET) were the primary polymers, according to μ-Raman spectroscopy. The fish species Liza tade and Etroplus suratensis showed the highest levels of contamination, while the shellfish species Portunus sanguinolentus and Scylla serrata did the same. Comparative global analyses reveal that mangrove ecosystems across different regions exhibit the presence of similar polymer types, but microplastic sources vary greatly from place to place. This work highlights the pervasive nature of MPs, their complex seasonal behavior, and their ecological implications, advocating for targeted mitigation strategies to address MP pollution and its potential risks to marine life and ecosystems.

Unearthing the hidden plastic in garden compost

Compost and potting mixes have emerged as significant sources of plastic and biodegradable polymer residues in soil. While bio-based (such as polylactic acid (PLA), polyhydroxyalkanoates (PHAs) and polybutylene succinate (PBS)) and fossil-based (such as polycaprolactone (PCL), and polybutylene adipate terephthalate (PBAT)) biodegradable polymers are designed to rapidly degrade and are marketed as biodegradable, they require specific conditions to do so. Consequently, both conventional and biodegradable plastic polymers raise concerns that they may be harming the environment. Compost is widely used to improve soil properties, but the presence of conventional and biodegradable plastic polymers in compost is not well understood. This study used pyrolysis coupled to gas chromatography mass spectrometry (Pyr-GC-MS) to investigate the prevalence of selected plastic polymers in commercial potting mix/composts and homemade composts in Australia. Polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET), polycarbonate (PC) and polyvinyl chloride (PVC) and the biodegradable polymers polylactic acid (PLA), polybutylene succinate (PBS), and polyhydroxyalkonaotes (PHA) were investigated. While PE and PVC polymer markers were assessed, they were not included in the results due to potential interferences. PP, PMMA and PET were present in only 1 sample at 0.18 mg/g d.w., 0.18 mg/g d.w. and 0.12 mg/g d.w. respectively, while PC was present in 2 samples, with a mean concentration of 0.04 mg/g d.w. and PS was below detection limits. PLA was detected in only one sample at 0.09 μg/g d.w., while PBS was present in all samples, with concentrations ranging from 0.02 to 0.39 μg/g d.w. PHA was found in two samples, at 0.03 μg/g d.w. and 0.09 μg/g d.w. and PCL and PBAT were not detected in any sample. Finally, the potential application of plastics to domestic gardens in Australia, through the application of compost/potting mix materials, was calculated to be between 0.02 and 0.6 g/m2, based on typical application rates and plastic content.

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.

Effects of microplastics on the immune system: How much should we worry?

Plastics are everywhere. It is widely recognized that they represent a global problem, the extent of which is yet to be defined. Humans are broadly exposed to plastics, whose effects and consequences are poorly characterized so far. The main route of exposure is via alimentary and respiratory intake. Plastics pollutions may come from both: water and food contamination itself, and their packaging. The smaller sizes (i.e. microplastics <150 µm - MPs) are considered to be the most pervasive of living organisms and, therefore, potentially the most harmful. As humans occupy one of the apex positions of the food chain, we are exposed to bioaccumulation and biomagnification effects of MPs. In fact, MPs are commonly found in human stools and blood. However, there are no data available yet on their ability to accumulate and to produce detrimental consequences on biological systems. Even though the effects of plastics pollution are poorly studied in mammals, including humans, they appear to have inflammatory effects, which is rather concerning as many etiologies of disease are based on a pro-inflammatory status.

From bulk to bits: understanding the degradation dynamics from plastics to microplastics, geographical influences and analytical approaches

The popularity of plastics in major application sectors is creating an increasing burden of pollutants in the environment in the forms of plastics and microplastics. More than 6 billion tons of plastics now reside in the environment, which is now an available source of secondary microplastics. Research focused on the degradation of plastics/microplastics dealing with different environmental conditions and their change in properties. Despite being a serious pollutant, sufficient resources are still missing for the transformation of secondary microplastics from large plastics and how to detect the level of degradation before this transition. This article's brief review provides insight into the current scenario of plastics, disposed waste plastics, management system, and their limitations. In addition, a detailed explanation of the transition of plastics to microplastics, their mechanism, and the effect of different geographical conditions on degradation is also demonstrated. Moreover, the available analytical techniques to understand the degradation index of different polymers are also described in addition to the future perspectives for research in this area. This review could provide valuable insight into the formation of microplastics from waste plastics and their mechanisms in addition to a comprehensive knowledge of the quantification of the degradation.

Measurement and daily consumption of microplastics in drinking water from a Small Island Developing State-Fiji: from freshwater to groundwater sources

The occurrence of microplastics (MPs) in drinking water has emerged as a significant source of this contaminant, posing an increased risk to human health. These MPs are now of extreme concern, especially on the possible harmful effects it may have on human health. This study is the first baseline MPs data in drinking water from Fiji. Raw, treated, tap, rain, ground, and bottled water were investigated for the presence of MPs and the ingestion rate by the different age groups. The analytical procedure was validated by determining recovery rates and analyses of blanks. The detection limit of the MPs was 10 µm, while fibers and particles ≥ 100 µm were analyzed on 100% of the filter area. The abundance of MPs in drinking water was source-dependent. Percentage removal of MPs from water treatment plants was 45-67%, resulting in the presence of 0.10 ± 0.03 to 2.90 ± 0.57 MPs L-1 in tap water. The presence of MPs in bottled, rain, and groundwater was in the range of 0 to 2.20 ± 0.41 MPs L-1. Fiber MPs predominated in all water sources except for bottled water. Main types of polymer identified were polyethylene, polypropylene, and poly(ethylene terephthalate). Estimated daily intake of MPs in tap water by children and adults were 0.0031-0.1813 and 0.0021-0.0829 MPs/kg bw/day, respectively. Information from this work in combination with information from the health sector will help to fully understand microplastic impact on human health and the actions that are required to mitigate it.

Microplastic pollution inhibits the phagocytosis of E. coli by earthworm immune cells in soil

It has not been known how immune responses in soil invertebrates occur against microplastics (MPs). This study aims to investigate the effects of MPs on endocytosis, including phagocytosis and pinocytosis, of immune cells of soil invertebrates in the soil ecosystem in the process of bacterial infection. We employed polystyrene microplastics (∼ 1 μm PS MPs) to treat earthworm Eisenia andrei during the infection of Escherichia coli for in vitro (1, 5, 10, and 50 mg/L) and in vivo (1, 10, and 1000 mg/kg dry soil) assays. The results of in vitro migration assay revealed that MPs caused inhibitory effects on the phagocytosis, pinocytosis and oxidative stress in coelomocytes. Soil bioassay also confirmed that endocytosis of coelomocytes and mitochondrial damages in the intestinal epithelium were significantly altered in the polluted soil with MPs. Thus, MPs induced adverse effects to inhibit bacterial endocytosis, which may disturb the immune system of soil invertebrates. This study is the first report on the inhibition of phagocytosis in the soil invertebrates by MPs. These findings contribute to understanding the response of soil invertebrates, which play important roles in the soil food web with cellular level towards microplastic pollution in soil.

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.

Exposure to volatile organic compounds and chronic respiratory disease mortality, a case-cohort study

BACKGROUND

Chronic respiratory diseases (CRDs) are the third leading cause of death worldwide. Data of the associations between specific volatile organic compounds (VOCs), a major component of air pollution and tobacco smoke, and subsequent CRD mortality in the general population are scarce.

METHODS

In a case-cohort analysis within the population-based Golestan cohort study (n = 50045, aged 40-75 years, 58% women, enrollment: 2004-2008, northeastern Iran), we included all participants who died from CRD during follow-up through 2018 (n = 242) as cases and stratified them into 16 strata defined by age, sex, residence, and tobacco smoking. Subcohort participants (n = 610) were randomly selected from all eligible cohort participants in each stratum, and sampling fractions were calculated. Baseline urine samples were used to measure 20 VOCs using ultra high-performance liquid chromatography coupled with electrospray ionization tandem mass spectrometry. After excluding participants with previous history of CRDs, we used stratified Cox regression models weighted by the inverse sampling fractions (i.e. inverse probability weighting) adjusted for potential confounders, including urinary cotinine and pack-years of smoking, to calculate hazard ratios (HR) for the associations between biomarker tertiles and CRD mortality.

RESULTS

Data from 545 non-case, sub-cohort participants and 149 cases (69.1% chronic obstructive pulmonary disease, 13.4% asthma, 17.5% other CRDs) were assessed in this study. During a follow-up of 10.5 years, associations [2nd and 3rd vs. 1st tertiles, HR (95% confidence interval), p for trend] were observed between metabolites of acrolein [1.56 (0.64,3.79), 3.53 (1.53,8.16), 0.002] and styrene/ethylbenzene [1.17 (0.53,2.60), 3.24 (1.37,7.66), 0.005] and CRD mortality, which persisted after excluding the first four years of follow-up.

CONCLUSION

Our findings support prior research suggesting respiratory toxicity of VOCs. Further investigation and monitoring of these compounds, especially acrolein and styrene/ethylbenzene, as CRD risk factors, are recommended.

Synergistic human health risks of microplastics and co-contaminants: A quantitative risk assessment in water

The pervasive presence of microplastics (MPs) in aquatic environments, coupled with their potential to act as vectors for toxic contaminants, raises significant concerns for human health. This study quantifies the health risks associated with the ingestion of microplastics and their co-contaminants in aquatic medium, considering both individual and interactive effects. The analysis encompasses four MP types (PP, PS, PET, PE) and prevalent contaminants including heavy metals (Cr, Cu, Ni, Pb), polycyclic aromatic hydrocarbons (PAHs, expressed as BaP equivalents), and plastic additives (DEHP, DBP, BPA)-to calculate individual Hazard Quotient (HQ), interaction-based Hazard Index (HIint), individual Incremental Lifetime Cancer Risk (ILCR), and interaction-based ILCR (ILCRint). The mean concentration of MPs in aqueous media was determined to be 2.19 mg/L (95 % CI), and Chronic Daily Intake (CDI) values were derived from particle counts converted to mass using polymer-specific densities. Reference Dose (RfD) values were calculated using the Weight of Evidence (WoE) approach, which integrates findings from rodent toxicity studies, identifying PP and PS as having low RfD values 25 × 10⁻⁴ mg/kg bw/day and 8 × 10⁻⁴ mg/kg bw/day, respectively. HQ-based toxicity rankings indicated the order of risk as PP > PS > PE > PET. Findings revealed a pronounced HIint of 18.646 × 10³ and 16.649 × 10⁶ at the 50th and 90th percentiles in children, underscoring significant synergistic effects from combined exposure to MPs and leached plastic additives. Co-contaminant scenarios further escalated health risks, with HI values reaching 52.236 in the presence of heavy metals and 53.141 with PAHs. The maximum allowable MP concentration, considering additive leaching, was estimated at 0.011 mg/L. This research highlights the need for firstly understanding the transformations of microplastic in the aquatic medium along with co-contaminants and framing regulatory measures and improved monitoring to protect human health from the growing threat of microplastic pollution. By integrating exposure modeling, dose-response assessment, and Monte Carlo simulations, the study delivers a robust framework for environmental health guidelines. It emphasizes the complex, multifaceted risks MPs pose and their associated contaminants, calling for innovative solutions to safeguard public health against this pervasive environmental challenge.

Toxic effects of microplastics (polyethylene) exposure on acetylcholinesterase, stress indicators and immunity in Korean Bullhead, Pseudobagrus fulvidraco

Microplastics (MPs) in aquatic environments can have toxic effects on various organisms, including fish. This study exposed Pseudobagrus fulvidraco to polyethylene MPs at 0, 10 mg/L (approximately 9.50 ×108 particles/L), 20 mg/L (approximately 1.9 ×109 particles/L), 5000 mg/L (approximately 4.75 ×1011 particles/L), and 10,000 mg/L (approximately 9.50 ×1011 particles/L) concentrations for 96 h. At relatively lower MPs concentrations (0, 10 and 20 mg/L), no significant changes were observed in acetylcholinesterase (AChE) activity, stress indicators (heat shock protein 70 and cortisol), or immune responses (lysozyme activity and immunoglobulin M levels). However, at higher MPs concentrations (5000 and 10,000 mg/L), AChE activity was significantly inhibited, stress indicators were significantly increased, and immune responses were significantly decreased. Our results indicate that acute exposure of P. fulvidraco to MPs had negligible effects at concentrations below 20 mg/L, whereas significant toxic effects such as AChE activity inhibition, stress responses, and immune suppression were observed at concentrations above 5000 mg/L. Therefore, our study highlights the risks of severe MPs pollution on aquatic ecosystems and fish health.

Investigation of potential toxic effects of nano- and microplastics on human endometrial stromal cells

Nanoplastics (NPs) and microplastics (MPs) have become a global concern in recent years. Most current research on the impact of plastics on obstetrics has focused on their accumulation in specific tissues in animal models and the disease-causing potential of MPs. However, there is a relative lack of research on the cellular changes caused by the accumulation of MPs. In this study, we aimed to establish a proper in vitro exposure protocol for polystyrene (PS)-NPs and MPs and to investigate possible cytotoxic effects of PS-NPs and MPs on human endometrial stromal cells (ESCs) using different plastic sizes and concentrations. The results showed that smaller plastics, specifically 100 nm PS-NPs and 1 μm PS-MPs, had a higher cellular uptake propensity than larger particles, such as 5 μm PS-MPs, with significant morphological changes and cell death observed at concentrations above 100 μg/mL a 24-h period. In addition, confocal microscopy and real-time imaging confirmed the accumulation of these particles in the nucleus and cytoplasm, with internalization rates correlating with particle size. Also, 100 nm PS-NPs reduced cell proliferation and induced apoptosis. In conclusion, this study demonstrates that exposure to 100 nm PS-NPs and 1 μm PS-MPs leads to dynamic accumulation in ESCs, resulting in cell death or decreased proliferation at specific concentrations, which highlights the potential cellular toxicity of NPs or MPs.

Biochar-based electrochemical sensors: a tailored approach to environmental monitoring

Biochar (BC), often obtained via thermochemical conversion methods of biomass, has emerged as a versatile material with significant potential in electrochemical sensing applications. This review critically examines the recent advancements in the development of BC-based sensors for the electrochemical determination of pharmaceuticals, pesticides, heavy metals, phenolic compounds, and microplastics. BC-based electrochemical sensors have emerged as a promising alternative due to their sustainability, cost-effectiveness, and excellent electrochemical properties. The unique physicochemical properties of BC, including its high surface area, porosity, and functional groups, contribute to its effectiveness as a sensor material. The review begins with an overview of the synthesis methods for BC, highlighting the activation strategies on its structural and electrochemical properties. Next, the functionalization of BC and its integration into electrochemical sensor platforms are explored. The performance of BC-based sensors is evaluated using electrochemical focusing on their sensitivity, selectivity, detection limits, and stability. Future directions for research are proposed, emphasizing the need for further optimization, miniaturization, and integration of BC-based sensors into portable and on-site analytical devices.

Uncovering layer by layer the risk of nanoplastics to the environment and human health

Nanoplastics (NPs), defined as plastic particles with dimensions less than 100 nm, have emerged as a persistent environmental contaminant with potential risk to both environment and human health. Nanoplastics might translocate across biological barriers and accumulate in vital organs, leading to inflammatory responses, oxidative stress, and genotoxicity, already reported in several organisms. Disruptions to cellular functions, hormonal balance, and immune responses were also linked to NPs exposure in in vitro assays. Further, NPs have been found to adsorb other pollutants, such as persistent organic pollutants (POPs), and leach additives potentially amplifying their advere impacts, increasing the threat to organisms greater than NPs alone. However, NPs toxic effects remain largely unexplored, requiring further research to elucidate potential risks to human health, especially their accumulation, degradation, migration, interactions with the biological systems and long-term consequences of chronic exposure to these compounds. This review provides an overview of the current state-of-art regarding NPs interactions with environmental pollutants and with biological mechanisms and toxicity within cells.

First Evidence of Microplastics Burden in Surface Waters of Budhabalanga Estuary, Chandipur, Eastern India: Potential Threat to Aquatic Ecosystem

Microplastic pollution has emerged as a new global concern because of its ubiquitous and persistent nature. Due to the rising use of plastics and discharge of plastic waste into coastal water bodies from point and non-point sources, the occurrence of microplastics along coastal ecosystems has become very prevalent. The current study is the first of its kind to evaluate the presence of microplastics in the surface water of river estuary along the coast of Odisha. Six GPS-fixed locations were used to collect the surface water samples from the Budhabalanga river estuary in Chandipur, Odisha, India. The samples were then subjected to further investigation to determine the types of microplastics present. The average microplastic abundance, according to our findings, ranged from 9.33 ± 2.11 items L-1 to 28.50 ± 2.77 items L-1. Microplastics come in a variety of colours and shapes, but the most prevalent kind is fibre-shaped and black in colour. The pollution load index of the sampling area was calculated to be 4.25 which is categorized under ecological risk level I. FE-SEM images clearly showed the topology of microplastics and ATR-FTIR analysis confirmed the presence of polyethylene, polypropylene, polyvinyl chloride (PVC), nylon, polycarbonate (PC), ethylene vinyl acetate (EVA) and polystyrene (PS) at sampling stations. Our investigation provides useful information that helps to reduce the ecological risk in habitats connected with contaminated sites, including both aquatic and terrestrial habitats.

A preliminary assessment of microplastics in the waters and sediments of the second-largest freshwater lagoon in India

Pulicat is India's second-largest freshwater lagoon having unique biological ecosystem and economical importance. The lagoon systems are highly polluted by the microplastics (MP) due to anthropogenic activity and microplastics are highly emerging kind of contaminant in the environment. Samples were collected from a part of the lagoon near the mouth region. Morphological identification of microplastics with microscope and polymer identification using ATR-FTIR and Micro-Raman spectroscopy was carried out. From the result, average abundance of the MP particles in surface water ranges 3.12 ± 1.53 particles per 1000 l and 701 ± 198 particles per kg for sediments, respectively. Microplastics < 1 mm (1-1000 microns) are dominant in size. Fibres, fragments and films were most occupied in physical form, respectively, in microplastic samples and polypropylene (PP) and polyethylene (PE) were the predominant polymer types composited in MP particles. This study concludes that Pulicat lagoon is significantly polluted by microplastic, which is mostly contributed by fishing and mismanagement of plastic wastes.

Identification and occurrence of microplastics in drinking water bottles and milk packaging consumed by humans daily

Microplastic (MP) pollution has become a growing concern due to its potential environmental and health impacts. The present study aimed to investigate the presence of MPs in specific brands of drinking water bottle and milk packets. To identify the MPs, researchers employed microscopic techniques, FTIR spectroscopy, and FESEM with EDS. The types of polymers were determined by comparing the obtained values with reference standards. The study also assessed the potential daily microplastic exposure from drinking water and milk consumption. MPs were detected in the samples in three different shapes: filaments, fibers, and fragments. Four types of polymers were identified: polypropylene (PP), polyamide (PA), polysulfone (PSU), and polyethersulfone (PES). The colors observed included violet, blue, green, red, and black. In the analyzed drinking water samples, a total of 13 MPs sized 1-3 mm and 7 MPs sized 3-6 mm were found. In the milk samples, there were 2 MPs sized 4-5 mm and 4 MPs sized 2-3 mm. The results of the study indicate that MPs are present in the examined drinking water and milk, which are directly consumed by humans. This suggests that microplastic pollution may occur during the manufacturing or packaging processes of these products. The study recommends implementing measures to reduce microplastic contamination at the beginning of the production process for drinking water and milk.

Production of polyhydroxyalkanoate from new isolated bacteria of Acidovorax diaphorobacter ZCH-15 using orange peel and its underlying metabolic mechanisms

Polyhydroxyalkanoate (PHA) is considered a sustainable alternative to traditional petroleum-based plastics due to its biodegradability and biocompatibility. In this study, Acidovorax diaphorobacter ZCH-15, an efficient PHA-producing strain, was isolated from activated sludge. Using food waste-derived orange peel as a substrate, the strain initially achieved a PHA concentration of 0.39 g/L. Under optimal fermentation conditions (30℃, pH 8, 2 % inoculum concentration, and 30 g/L carbon source), the PHA concentration increased by 138 % to reach a maximum of 0.93 g/L. Proton nuclear magnetic resonance spectroscopy and gas chromatography analyses identified the PHA composition as poly(3-hydroxybutyrate-co-3-hydroxyvalerate), which exhibited high crystallinity and structural stability. Metabolomic analysis indicated that the tricarboxylic acid cycle and pentose phosphate pathway were involved in producing succinyl-CoA, a precursor required for PHA synthesis. This study demonstrates the potential for cost-effective industrial PHA production while enabling the high-value utilization of food waste.

Characterization of microplastics in human follicular fluid and assessment of their potential impact on mouse oocyte maturation in vitro

Microplastics (MPs) have been identified in various human tissues and organs. This study aims to evaluate the presence of MPs in human follicular fluid (hFF) and their potential impact on oocyte maturation. Laser direct infrared spectroscopy of 19 hFF samples identified 7956 particles, including 1739 microplastics (21.9 %) from 30 types. Of these, 923 particles had matching degrees > 0.8, and 7033 had matching degrees between 0.65 and 0.8. The most abundant MPs were Chlorinated Polyethylene (CPE), Fluorosilicone rubber, Polyvinyl chloride (PVC), Butadiene rubber (BR), and Styrene-butadiene-styrene (SBS), with diameters ranging from 20 to 100 μm. Five random samples were analyzed by pyrolysis-gas chromatography-mass spectrometry, which detected four types of microplastics-Polyethylene (PE), Polypropylene (PP), Polystyrene (PS), and PVC-at varying concentrations. PE was the most abundant (22.284 mg/kg), followed by PVC (1.061 mg/kg), PP (0.837 mg/kg), and PS (0.600 mg/kg). Based on the diameter and concentration ranges of MPs in hFF, we used seven types of fluorescence-labeled MP beads-PE, PVC, PP, PS, CPE, Polymethylmethacrylate (PMMA), and Polytetrafluoroethylene (PTFE)-to assess their impact on mouse oocyte in vitro maturation. The results showed that smaller MP beads (e.g., 50 μm PE) were more likely to penetrate the zona pellucida and enter the oocyte, while larger beads (e.g., 500 nm PMMA) tended to adhere to the zona and remain outside the oocyte. All seven types of MP beads hindered oocyte maturation, resulting in varying reductions in maturation rates compared to the control group. Our findings suggest that MPs contaminate hFF and may impair oocyte maturation.

Characterization and risk assessment of microplastics in shoreline sediments of the Yellow River Delta

As the intersection of river, sea, and land, river deltas are hotspots for the accumulation of microplastics (MPs). This study investigated the abundance and characteristics of MPs in surface sediments from shoreline area of the Yellow River Delta in northern China, elucidated their sources, and assessed their risk. The MPs isolated from sediment samples were detected and characterized using optical microscopy and micro-Fourier transform infrared spectroscopy (μ-FTIR). The results showed that MPs were abundant (360-2160 items/kg) in the area, and occurred mainly in small sizes (<250 μm), as fibers (20.2-50.0%), filament (4.8-21.5%), and granules (8.5-20.6%), and in transparent (27.8-40.3%), blue (11.2-31.6%), or black (7.9-26.5%) color. Polyethylene terephthalate (26.08%), polyethylene (20.47%), polypropylene (13.49%), and polyvinyl chloride (10.71%) were the dominant polymer types for the MPs. The pollution load indices (1-6) indicated that all sampling sites were polluted by MPs, while the polymeric hazard indices (65.14-91.44) suggested that MPs pollution of the area was in medium range. Overall, the ecological risk indices (91.44-475.38) of the sampling sites indicated that MPs in shoreline sediments of the Yellow River Delta posed low to considerable potential ecological risk. While the dominance of polymers with medium polymeric risk scores rendered the MPs in the shoreline sediments with relatively low risk, the majority of MPs occurred in small sizes, which complicates the actual risk posed by MPs in shoreline sediments of the Yellow River Delta and deserves attention.

Microplastics in the surface waters of the northern South China Sea: Interannual variation and potential ecological risks

Microplastic pollution in marine environments has become a global concern due to its potential ecological risks. However, long-term data on microplastic distribution are scare, hindering the assessment of the ecological threats. This study monitored microplastics pollution in the surface water of the northern South China Sea from 2019 to 2023. The average abundance of microplastics exhibited an increasing trend from 2019 to 2021 and a subsequent decrease from 2021 to 2023 in both the Pearl River Estuary and Zhanjiang offshore waters. Conversely, a steady annual decrease was observed in the surface waters of Beibu Gulf from 2020 to 2023. The spatial variability of microplastic hotspot across different years and regions. Microplastics predominantly ranged from 1 to 2 mm in size, with fragments and fibers being the most common shapes and transparent and white colors being the most prevalent. The primary chemical components of microplastics were polyethylene (PE), polypropylene (PP), and polyethylene terephthalate (PET). No significant inter-annual differences were observed in the physicochemical characteristics of microplastics. The pollution load index (PLI) indicated medium to low levels of microplastic pollution, with the potential ecological risk index (PERI) suggesting a low level of ecological risk, implying a minimal threat to the marine ecosystem. This study first revealed the annual variations in microplastic pollution and their potential ecological risks in the northern South China Sea, providing crucial data support for the future management and control of marine microplastic pollution.

Can agriculture and food waste be a solution to reduce environmental impact of plastic pollution? zero-waste approach for sustainable clean environment

Agriculture and food waste, especially from fruits, vegetables, and plant byproducts like banana peels, avocado seeds, and durian seeds, have emerged as promising alternatives for bioplastic production. These materials, rich in polysaccharides and cellulose, offer a sustainable solution to reduce plastic pollution and mitigate the environmental impact of traditional plastics. This review focuses on the potential of utilizing agricultural and food waste to create starch-based bioplastics, emphasizing the importance of a zero-waste approach to enhance the economic value of these byproducts while promoting a cleaner environment. We include a SWOT analysis of this innovative approach, assess the environmental implications of bioplastic production, and highlight the potential for turning agricultural waste into a key player in the fight against plastic pollution. This review also explores the future prospects of harnessing agriculture and food waste as valuable resources for sustainable bioplastics, contributing to a greener, more sustainable world.

Comprehensive Review on Bio-Based Treatments for Polyvinyl Chloride Plastic

Polyvinyl chloride (PVC) plastics are widespread around the globe, and each year, thousands of tons of PVC end up in the environment in the form of micro-/nanoplastics. Literature has reported extensively on the biodegradation of its PVC additives/plasticizers; however, bio-based treatment approaches for its polymers have been scanty. The current review has discussed elaborately all possible PVC degradation processes and the toxicity challenges faced during its mitigation. This review has also delineated and assessed all physical, chemical, and biological approaches reported for PVC treatments. All the biodeterioration, biocatalysis, and biodegradation mechanisms reported for PVC have been comprehensively discussed. Recent advances have also been highlighted like the direct application of invertebrate species and selective enzymes like peroxidases, alkane monooxygenase, and laccase during PVC treatment. Insights of functional genomes/genes and OMICS have been recommended, which might help predict and address any future issues during the mitigation of PVC pollution in the environment.

Influence of selected dosages of plastic microparticles on the porcine fecal microbiome

Studies conducted so far have shown that nano- and microplastic may disturb the intestinal microenvironment by interacting with the intestinal epithelium and the gut microbiota. Depending on the research model used, the effect on the microbiome is different-an increase or decrease in selected taxa resulting in the development of dysbiosis. Dysbiosis may be associated with intestinal inflammation, development of mental disorders or diabetes. The aim of the study was to analyze the intestinal microbiome in 15 gilts divided into 3 research groups (n = 5; control group, receiving micropartices at a dose 0.1 g/day (LD) and 1 g/day (HD)). Feaces were collected before and after 28 days of exposure to PET microplastics. The analysis of the intestinal microbiome was performed using next-generation sequencing. Alpha and beta diversity indices were compared, showing, that repetition affected only the abundance indices in the control and LD groups, but not in the HD group. The relationships between the number of reads at the phylum, genus and species level and the microplastic dose were calculated using statistical methods (r-Pearson correlation, generalized regression model, analysis of variance). The statistical analysis revealed, that populations of Family XIII AD3011 group, Coprococcus, V9D2013 group, UCG-010 and Sphaerochaeta increased with increasing MP-PET dose. The above-mentioned taxa are mainly responsible for the production of short-chain fatty acids (SCFA). It may be assumed, that SCFA are one of the mechanisms involved in the response to oral exposure to MP-PET.

Food packaging solutions in the post-per- and polyfluoroalkyl substances (PFAS) and microplastics era: A review of functions, materials, and bio-based alternatives

Food packaging (FP) is essential for preserving food quality, safety, and extending shelf-life. However, growing concerns about the environmental and health impacts of conventional packaging materials, particularly per- and polyfluoroalkyl substances (PFAS) and microplastics, are driving a major transformation in FP design. PFAS, synthetic compounds with dual hydro- and lipophobicity, have been widely employed in food packaging materials (FPMs) to impart desirable water and grease repellency. However, PFAS bioaccumulate in the human body and have been linked to multiple health effects, including immune system dysfunction, cancer, and developmental problems. The detection of microplastics in various FPMs has raised significant concerns regarding their potential migration into food and subsequent ingestion. This comprehensive review examines the current landscape of FPMs, their functions, and physicochemical properties to put into perspective why there is widespread use of PFAS and microplastics in FPMs. The review then addresses the challenges posed by PFAS and microplastics, emphasizing the urgent need for sustainable and bio-based alternatives. We highlight promising advancements in sustainable and renewable materials, including plant-derived polysaccharides, proteins, and waxes, as well as recycled and upcycled materials. The integration of these sustainable materials into active packaging systems is also examined, indicating innovations in oxygen scavengers, moisture absorbers, and antimicrobial packaging. The review concludes by identifying key research gaps and future directions, including the need for comprehensive life cycle assessments and strategies to improve scalability and cost-effectiveness. As the FP industry evolves, a holistic approach considering environmental impact, functionality, and consumer acceptance will be crucial in developing truly sustainable packaging solutions.

Microplastics in Morocco's most consumed fisheries: Chemical characterization, ecological traits, and implications for human health

The pervasive presence of microplastics (MPs) in the environment is well established, yet many critical questions remain about their distribution and potential impacts on both ecological and human health. To assess the risks that MPs pose, especially through marine ecosystems and human consumption, monitoring their ingestion by fish in natural environments is essential. This study investigated the contamination of 12 fish species, the most commonly consumed in Morocco, collected from the Atlantic Ocean off the Moroccan coast. Analysis of 240 fish (20 individuals per species) revealed that 100 % of the samples contained microplastics. MPs were detected in the gills, gonads, and gastrointestinal tracts of all 12 species. The average abundance of microplastics per fish ranged from 20.6 to 133.2 MPs, with the forms identified as fragments (60 %), fibers (30 %), films (8 %), and pellets and foams (1 %). Additionally, omnivorous and demersal species presented the highest levels of MP contamination. Infrared spectroscopy (ATR-FTIR) analysis identified seven polymers, with high-density polyethylene (34 %), polyethylene terephthalate (30 %), and polypropylene (17.5 %) being the most prevalent. The microplastics were predominantly dark or light in color, with a notable presence of red and blue particles. Fish ingest various sizes of microplastics, primarily particles smaller than 1 mm. Scanning electron microscopy coupled with energy dispersive X-ray analysis (SEM/EDX) revealed that most MPs exhibited visible signs of weathering and contained inorganic components on their surfaces. The potential risk of MPs to fish, as assessed by the polymer hazard index (PHI), was categorized as level V, indicating that MPs may pose significant risks to human health. The highest estimated daily intake (EDI) of microplastics was found in children (1620 MPs/year), whereas the lowest intake was estimated in women (350 MPs/year) and men (337 MPs/year). Given the widespread presence of microplastics in commonly consumed fish species in Morocco, there is an urgent need for regulatory measures to ensure the safety of fisheries, both for domestic consumption and export. Policymakers should consider the development of guidelines for acceptable levels of microplastic contamination in fish to safeguard public health.

Association between urinary volatile organic compounds metabolites and rheumatoid arthritis among the adults from NHANES 2011-2018

Rheumatoid arthritis (RA) is closely associated with environmental factors. Volatile organic compounds (VOCs) are a common environment pollutant which can induce autoimmune diseases. However, studies on the relationship between VOCs and RA are still unclear. This study aimed to evaluate the potential associations between exposure to urinary VOCs and RA risk among adults. Data was analyzed from the National Health and Nutrition Examination Survey (NHANES) 2011-2018. We used logistics regression, restricted cubic splines (RCS) model, (Weighted Quantile Sum) WQS, qgcomp and (Bayesian Kernel Machine Regression) BKMR models to assess single and mixed relationships between VOCs and RA. A total of 3390 participants and 15 urinary VOCs included in this study. The results showed that AMCC, CEMC, DHBC, MB3C, PHGA, and PMMC were significantly higher than in RA compare to the participants without RA. Logistic regression model reveals that AAMC, AMCC, CEMC, CYMC, DHBC, HPMC, and MB3C were positive correlation with RA which age between 20 and 50. Then the WQS, qgcomp, and BKMR model suggest a positive association between mixed urinary VOCs and RA, with WQS and qgcomp model highlighting CYMC and CEMC as the major contributors in age 20-59 group. In BKMR analysis, the overall effects of co-exposure displayed CYMC, CEMC, and AMCC has significant positive with RA in age 20-59. Furthermore, RCS regression proved the positive linear relationship between CYMC, AMCC, and CEMC with RA. According to our study results, we demonstrated that exposure to certain urinary VOCs (CYMC, CEMC, and AMCC) is associated with an increased prevalence of RA among adults that age 20-59.

Current status of microplastic pollution and the latest treatment technologies

With the widespread use of plastics globally, the issue of microplastic (MP) pollution has escalated into a significant social and environmental concern. This paper seeks to comprehensively review the environmental hazards associated with MPs and to present the latest analytical techniques and countermeasures. By analyzing the global distribution of MPs and the hazards they pose to the human body, it is found that MPs come from a variety of sources and are widely distributed, and that their hazards cover the whole body, but there is a lack of specific dose analyses and acute toxicity analyses. To address the challenges of industrial-scale MP treatment, numerous advanced theories and methods have been developed, providing valuable insights for effective remediation. Despite these advancements, notable limitations persist, particularly in the treatment of MPs in residential water supplies. Furthermore, this review identifies promising approaches in the utilization of microorganisms and the synergistic mechanisms of enzymes for MP pollution mitigation. Additionally, the urgent need for the development of standardized methods and a comprehensive legal framework for the isolation and detection of MPs across various environmental media is underscored, providing novel perspectives on the study of MPs.

Investigating the determinants of Singaporean citizens' attitudes toward marine litter pollution control: A policy acceptance model

The problem of marine litter has caused significant threat to marine environment and human health, and has attracted wide attention. It is estimated that the weight of plastic waste in the oceans will exceed that of fish by 2050. Since a large part of marine debris originate from land-based domestic waste, developing relevant policies to manage the disposal of domestic garbage can effectively prevent and control marine litter pollution. Public attitudes toward relevant environmental policies will affect their implementation and final outcomes. However, there is little research on public attitudes toward environmental policies. Therefore, this study draws on the framework of Technology Acceptance Model (TAM) to explore the factors that affect public attitudes toward policy, the affect theory, trust theory and habit are integrated into the model. An online survey for Singaporean residents was conducted, 450 questionnaires were collected and 417 of which were used for data analysis. The results suggest that 13 of the 14 hypotheses presented in the model are accepted. Perceived ease of implementation (β = 0.365), perceived policy effectiveness (β = 0.341) and trust in government policy (β = 0.319) are the main factors that directly affect citizens' attitude toward environmental policy. Perceived policy effectiveness is positively affected by the perceived ease of implementation (β = 0.457), while trust in government policies is positively influenced by both perceived ease of implementation (β = 0.142) and perceived policy effectiveness (β = 0.373). The model showed good explanatory power, explaining 74.6 % of the variance in public attitude toward policy. In this study, a relatively complete model for predicting public acceptance of marine litter prevention policies is proposed for the first time. The model presented in this paper also has the potential to be applied to evaluate policies of various scenarios.

Pollution status of microplastics in the sediments of warm monomictic Dal lake, India: Abundance, composition, and risk assessment

This report presents the first investigation of microplastic (MP) contamination in the shoreline sediments of Dal Lake, Jammu and Kashmir, India. The MP concentrations ranged from 503 to 3154 MP/kg, with a notable seasonal variation. The highest concentrations of microplastics occurred in the Spring, ranging from 467 to 3445 MP/kg. Microplastics were identified using optical microscopy, Fourier Transform Infrared spectroscopy, and thermogravimetric analysis. Polymer analysis revealed that the Gagribal basin was contaminated with polyethylene (PE), polypropylene (PP), polystyrene (PS), polyvinyl chloride (PVC), polyamide (PA), and polyethylene terephthalate (PET). In contrast, the Nigeen basin mainly comprises PE, PP, and PS. The significantly elevated Polymer Hazard Index (PHI) values, exceeding 1000 in the Gagribal basin, were attributed to the presence of PVC. Sediment quality was assessed using Pollution Load Index (PLI), Potential Ecological Risk Index (PERI), and PHI. Health risk metrics, such as estimated daily intake (EDI) and microplastic carcinogenic risks (MPCR), were also evaluated. There is a positive correlation between microplastic abundance and total organic carbon (TOC), total phosphorus (TP), and total nitrogen (TN). The Nigeen basin, characterized by a higher proportion of less hazardous polymers like PP, exhibited greater TOC levels due to enhanced microbial degradation of microplastics. Conversely, the Gagribal basin, with its higher presence of toxic polymers like PVC, had lower TOC levels, likely due to these compounds' inhibition of microbial activity. This study provides crucial insight into the spatial distribution and ecological impact of MPs in Dal Lake, setting the stage for future research on their effects on aquatic ecosystems.

Lightweight deep learning model for underwater waste segmentation based on sonar images

In recent years, the rapid accumulation of marine waste not only endangers the ecological environment but also causes seawater pollution. Traditional manual salvage methods often have low efficiency and pose safety risks to human operators, making automatic underwater waste recycling a mainstream approach. In this paper, we propose a lightweight multi-scale cross-level network for underwater waste segmentation based on sonar images that provides pixel-level location information and waste categories for autonomous underwater robots. In particular, we introduce hybrid perception and multi-scale attention modules to capture multi-scale contextual features and enhance high-level critical information, respectively. At the same time, we use sampling attention modules and cross-level interaction modules to achieve feature down-sampling and fuse detailed features and semantic features, respectively. Relevant experimental results indicate that our method outperforms other semantic segmentation models and achieves 74.66 % mIoU with only 0.68 M parameters. In particular, compared with the representative PIDNet Small model based on the convolutional neural network architecture, our method can improve the mIoU metric by 1.15 percentage points and can reduce model parameters by approximately 91 %. Compared with the representative SeaFormer T model based on the transformer architecture, our approach can improve the mIoU metric by 2.07 percentage points and can reduce model parameters by approximately 59 %. Our approach maintains a satisfactory balance between model parameters and segmentation performance. Our solution provides new insights into intelligent underwater waste recycling, which helps in promoting sustainable marine development.

The threat of microplastics and microbial degradation potential; a current perspective

Microplastics in marine environments come from various sources, and over the years, their buildup in marine environments suggests an inevitable need for the safe mitigation of plastic pollution. Microplastics are one of the chief and hazardous components of marine pollution, as they are transferred through the food chain to different trophic levels, affecting living organisms. They are also a source of transfer for pathogenic organisms. Upon transfer to humans, several toxic effects can occur. This review aims to assess the accumulation of microplastics in marine environments globally, the threat posed to humans, and the biodegradation potential of bacteria and fungi for future mitigation strategies. The versatility of bacteria and fungi in the biodegradation of different types of plastics has been discussed, with a focus on the microbial majority that has been cultivated in labs from the marine environment. We also propose that the exploration of yet-to-be-cultivated microbial majority can be a way forward for employing future strategies to mitigate microplastics.

Effects of cyanotoxins on nitrogen transformation in aquaculture systems with microplastics coexposure: Adsorption behavior, bacterial communities and functional genes

Microcystin-LR (MC-LR) and microplastics (MPs) have attracted increasing attention as important new pollutants in freshwater fishery environments. However, there are few reports on the effects of long-term combined MC-LR and MPs pollution on nitrogen transformation and microbial communities in aquaculture ponds, and the resulting risks have yet to be determined. Therefore, in this study, traditional refractory MPs (polystyrene, PS), biodegradable MPs (polylactic acid, PLA) and MC-LR, which are common in freshwater fishery environments in China, were selected as pollutants to construct a microcosm that simulates freshwater aquaculture ponds. MC-LR coexposure to PS and PLA was tested to reveal the effects of these pollutants on nitrogen transformation and microbial communities in aquaculture ponds, as well as to elucidate the potential risks posed by traditional refractory MPs and biodegradable MPs to freshwater aquaculture ecosystems. The results revealed that the MPs had a relatively high adsorption rate for MC-LR and that PS presented a relatively high adsorption capacity, whereas PLA presented a relatively high desorption capacity. Single or combined MPs and MC-LR pollution disrupted the normal nitrogen cycle in the aquaculture system, causing an overall loss of nitrogen in the water, and denitrification and nitrogen fixation in the water were inhibited to a certain extent through the inhibition of nitrogen cycle-related functional genes, with the PS + MC-LR group having the greatest inhibitory effect. In addition, compared with single-pollutant exposure, combined exposure to MC-LR and MPs had a greater effect on the microbial community composition. Analysis of the integrated biomarker response (IBR) index revealed that the risk of combined exposure to MC-LR and PS was greater than that of single exposure, so this phenomenon merits further attention.

Early-life exposure to polystyrene micro- and nanoplastics disrupts metabolic homeostasis and gut microbiota in juvenile mice with a size-dependent manner

Early-life exposure to different sizes of micro- and nanoplastics (MNPs) affects biotoxicity, which is related not only to the dose but also directly to particle size. In this study, pregnant ICR mice received drinking water containing 5 μm polystyrene microplastics (5 μm PS-MPs) or 0.05 μm polystyrene nanoplastics (0.05 μm PS-NPs) from pregnancy to the end of lactation. Histopathological and molecular biological detection, 16s rRNA sequencing for intestinal flora analysis, and targeted metabolomics analysis were used to look into how early-life exposure to MNPs of various sizes affects young mice's growth and development, gut flora, and metabolism. The outcomes showed that 0.05 μm and 5 μm PS-MNPs can pass through the placental and mammary barriers, and MNPs accumulating in various organs were size-dependent: the greater the accumulation in organs, the smaller the particle size. Further studies found that the larger 5 μm PS-MPs caused only small accumulation in organs, with the main health hazard being the disruption of intestinal barrier and liver function, indirectly causing gut dysbiosis and metabolic disorders. In contrast, the smaller 0.05 μm PS-NPs caused excessive accumulation in organs, not only impaired the function of the intestine and liver, but also caused direct mechanical damage to physical tissues, and ultimately resulted in more severe intestinal and metabolic disorders. Our findings underline the size-dependent risks associated with micro- and nanoplastics exposure early in life and highlight the necessity for tailored approaches to address health damages from early MNPs exposure.

Selective on-site detection and quantification of polystyrene microplastics in water using fluorescence-tagged peptides and electrochemical impedance spectroscopy

In this study, we developed a method for the on-site selective detection and quantification of microplastics in various water matrices using fluorescence-tagged peptides combined with electrochemical impedance spectroscopy (EIS). Among the types of plastics found in seawater, polystyrene (PS) microplastics were selected. Fluorometry, scanning electron microscopy (SEM), and Raman spectroscopy were used to verify the specific interaction of these peptides with PS spherical particles of different sizes (ranging from 0.1 to 250 µm). Principal component analysis (PCA) was employed to determine the effects of temperature (25-65 °C), incubation time (5 and 10 min), and particle size on plastic-peptide bonding efficiency, based on fluorescence intensity. For each water type (pure, tap, NaCl (0.5 M), and seawater), EIS plots (Nyquist and Bode) were generated. Significant factors affecting the EIS response, including particle size, shape, and material, were analyzed by measuring electrical parameters for different microplastic concentrations (50 ppb to 20 ppm). The EIS parameters changed with increasing plastic concentration, determining a limit of detection (LOD) of 50 ppb (ng/mL) for pure and tap water and 400 ppb for saline water, as the lowest concentration producing a significant change in EIS parameters compared to the baseline. The sensor proved highly effective for detecting microplastics in low ionic strength environments such as pure and tap water. However, in high ionic strength environments like saline and seawater, the detection capability diminished, likely due to the masking effect of ions on the EIS response.

Human exposure to micro/nano-plastics through vegetables, fruits, and grains - A predictive modelling approach

The emergence of human exposure (HE) to micro/nano-plastics (MN-P) via the food chain is a significant public health concern. This study aimed to evaluate HE from ingesting vegetables, fruits, and grains using linear regression models to analyse MN-P size-concentration relationships and bioaccumulation factors (BF). For Irish adults, the Estimated Daily Intake (EDI) of MN-Ps was calculated, considering potential internalisation in these foods, with a sensitivity analysis addressing variability and uncertainty. The simulated mean (SM) root stomatal diameter in selected plants was 620 nm, indicating the potential uptake of MN-Ps smaller than this size. The SM BF for vegetables was 24.24 for nanoplastics (NP). Limited NP data led to the use of metal nanoparticle (MNP) data, yielding an overall BF of 3.22 for pooled vegetables, fruits, and grains. Potential HE levels of MN-Ps in agricultural soil were simulated at 6.05 × 104 n/kg (SM), with predicted MN-P levels in edible plants at 1.47 × 106 n/kg of food products. The simulated EDI of MN-Ps through all crops was 1.62 × 103 n/kg bw/day, with vegetables contributing the most to MN-P exposure, followed by fruits and grains. Sensitivity parameters are ranked as MN-P abundance in soil > bioaccumulation factor > food consumption.

Selection of engineered degradation method to remove microplastics from aquatic environments

Microplastics (MPs) in the aquatic environment are difficult to degrade naturally due to their hydrophobicity and structure. A variety of engineered degradation methods were developed to treat MPs contamination in the aquatic environment. Current reviews of MPs degradation methods only provided an inventory but lacked systematic comparisons and application recommendations. However, selecting suitable degradation methods for different types of MPs contamination may be more effective. This work examined the present engineered degradation methods for MPs in the aquatic environment. They were categorized into chemical degradation, biodegradation, thermal degradation and photodegradation. These degradation methods were systematically summarized in terms of degradation efficiency, technical limitations and production of environmental hazards. Also, the potential influences of different environmental factors and media on degradation were analyzed, and the selection of degradation methods were suggested from the perspectives of contamination types and degradation mechanisms. Finally, the development trend and challenges for studying MPs engineered degradation were proposed. This work will contribute to a better selection of customized degradation methods for different types of MPs contamination scenarios in aquatic environments.

Possible sink of missing ocean plastic: Accumulation patterns in reef-building corals in the Gulf of Thailand

Individual coral polyps contain three distinct components-the surface mucus layer, tissue, and skeleton; each component may exhibit varying extent of microplastic (MP) accumulation and serve as a short- or long-term repository for these pollutants. However, the literature on MP accumulation in wild corals, particularly with respect to the different components, is limited. In this study, we investigated the adhesion and accumulation of MPs in four coral species, including both large (Lobophyllia sp. and Platygyra sinensis) and small (Pocillopora cf. damicornis and Porites lutea) polyp corals collected from Si Chang Island in the upper Gulf of Thailand. The results revealed that MP accumulation varied significantly among the four coral species and their components. Specifically, P. cf. damicornis exhibited the highest degree of accumulation (2.28 ± 0.34 particles g-1 w.w.) [Tukey's honestly significant difference (HSD) test, p < 0.05], particularly in their skeleton (52.63 %) and with a notable presence of high-density MPs (Fisher's extract test, p < 0.05). The most common MP morphotype was fragment, accounting for 75.29 % of the total MPs found in the coral. Notably, the majority of MPs were black, white, or blue, accounting for 36.20 %, 15.52 %, and 11.49 % of the samples, respectively. The predominant size range of MP particles was 101-200 μm. Nylon, polyacetylene, and polyethylene terephthalate (PET) were the prevalent polymer types, accounting for 20.11 %, 14.37 %, and 9.77 % of the identified samples, respectively. In the large polyp corals, while MP shapes, colors, and sizes exhibited consistent patterns, remarkable differences were noted in the polymer types across the three components. The findings of this study improve the understanding of MP accumulation and its fate in coral reef ecosystems, underscoring the need for further investigation into MP-accumulation patterns in reef-building corals worldwide.

Hazard assessment of microplastics and heavy metals contamination in Levant frogs (Pelophylax bedriagae): A bioindicator in Western Iran

The increasing pollution of aquatic ecosystems caused by microplastics (MPs) and heavy metal ions worldwide threatens the life of aquatic organisms, including amphibians. In this study, we investigated the presence and accumulation of MPs and heavy metal ions in the upper gastrointestinal tract (GIT) of the Levant frog (Pelophylax bedriagae) as a bioindicator in contaminated sites of Western Iran. A total of 192 adult frogs from 16 locations in the west and northwest of Iran were collected. We measured the accumulation of MPs and heavy metal ions in the collected frogs and determined the characteristics of MPs in the samples. Our findings revealed widespread MPs and heavy metal ions contamination in the frog GIT across all sampled stations. We found 742 MP particles in the digestive system of frogs, with the highest (7.09 MP/individual) and lowest (2.37 MP/individual) number observed in stations 10 and 9, respectively. Fibers were the most common MPs and polyester (PES) (42.5%) and polyethylene terephthalate (PET) (17.2%) were found to be the most common polymers in the GIT of frogs. The average accumulation of heavy metal ions showed significant differences (P < 0.05) among 16 sampling stations, and zinc (II) and mercury (II) showed the highest and lowest concentrations in frogs. We also found moderate to strong positive correlations between the detected MPs and heavy metal ions in the frog samples across all sampling stations. Our findings confirm the contamination of frogs by MPs and heavy metal ions and the potential capacity of MPs to increase the toxicity of heavy metals in P. bedriagae as a bioindicator in contaminated sites.

2D Materials for Potable Water Application: Basic Nanoarchitectonics and Recent Progresses

Water polluted by toxic chemicals due to waste from chemical/pharmaceuticals and harmful microbes such as E. Coli bacteria causes several fatal diseases; and therefore, water filtration is crucial for accessing clean and safe water necessary for good health. Conventional water filtration technologies include activated carbon filters, reverse osmosis, and ultrafiltration. However, they face several challenges, including high energy consumption, fouling, limited selectivity, inefficiencies in removing certain contaminants, dimensional control of pores, and structural/chemical changes at higher thermal conditions and upon prolonged usage of water filter. Recently, the advent of 2D materials such as graphene, BN, MoS2, MXenes, and so on opens new avenues for advanced water filtration systems. This review delves into the nanoarchitectonics of 2D materials for water filtration applications. The current state of water filtration technologies is explored, the inherent challenges they face are outlines, and the unique properties and advantages of 2D materials are highlighted. Furthermore, the scope of this review is discussed, which encompasses the synthesis, characterization, and application of various 2D materials in water filtration, providing insights into future research directions and potential industrial applications.

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.

Label-free impedimetric analysis of microplastics dispersed in aqueous media polluted by Pb2+ ions

The rapid differentiation between polluted and unpolluted microplastics (MPs) is critical for tracking their presence in the environment and underpinning their potential risks to humans. However, the quantitative analysis of polluted microplastics on the field is limited by the lack of rapid methods that do not need optical analysis nor their capture onto sophisticated electrochemical sensor platforms. Herein, a simple analytical approach for MPs dispersed in aqueous media leveraging electrochemical impedance spectroscopy (EIS) analysis on screen-printed sensors is presented. This method is demonstrated by the EIS-based analysis of two standards of microplastics beads (MPs), one of polystyrene (PS) and one of polystyrene carboxylated (PS-COOH), when exposed to aqueous solutions containing Pb2+ ions. The adsorption of Pb2+ ions on the MPs was quantitatively determined by voltammetric analysis. EIS permitted to rapidly (about 2 minutes) differentiate clean MPs from the Pb2+ polluted ones. These results could constitute a first-step towards the realization of a portable impedimetric sensor for the quantification of microplastics polluted by metal ions in aqueous solutions.

Investigation of cell-to-cell transfer of polystyrene microplastics through extracellular vesicle-mediated communication

Plastics are an essential part of human life and their production is increasing every year. Plastics degrade into small particles (<5 mm, microplastics, MPs) in the environment due to various factors. MPs are widely distributed in the environment, and all living organisms are exposed to the effects of MPs. Extracellular vesicles (EVs) are small membrane particles surrounded by a lipid bilayer that are released into the environment by various cell types and are highly involved in inter- and intra-cellular communication through the exchange of proteins, nucleic acids, and lipids between cells. There have been numerous reports of adverse effects associated with the accumulation of MPs in human and animal cells, with recent studies showing that plastic treatment increases the number of EVs released from cells, but the mechanisms by which MPs accumulate and move between cells remain unclear. In this study, we investigated whether polystyrene (PS)-MPs are transferred cell-to-cell via EVs. This study showed that cell-derived EVs can transport plastic particles. Furthermore, we confirmed the accumulation of PS-MPs transported by EVs within cells using a real-time imaging device. This study provides an understanding of potential EVs-mediated effects of PS-MPs on organisms and suggests directions for further research.

Ameliorative effects of Moringa oleifera leaf extract against arsenic induced histo-biochemical alterations in Labeo rohita

The current study evaluated the efficacy of Moringa oleifera leaf extract in mitigating the histo-biochemical alterations in Labeo rohita caused by arsenic. A medical plant (Moringa oleifera) known for its numerous pharmacological qualities, was added to three different diets at 0, 2, and 4 % level, prepared by mixing M. oleifera leaf extract with the basal diet. The 96 hr lethal concentration of arsenic to Labeo rohita was 20.25 mg L-1. One hundred and eighty healthy individuals of Labeo rohita were divided into four groups. One group served as control and other three groups were subjected to sub-lethal concentration 4.05 mg L-1 (1/5th of LC50) of arsenic, with or without Moringa oleifera leaf extract supplementation for 28 days. Fish exposed to arsenic experienced significant histological alterations, higher cortisol levels, impaired antioxidant status, elevated liver enzymes (ALT, AST, and ALP), and upregulated relative expression of the cytochrome P450 gene.". But, in fish fed with diets containing 2 % or 4 % M. oleifera leaf extract, the histological alterations were reduced, level of liver enzymes, cortisol and the upregulation of anti-oxidant enzyme and cytochrome P450 gene expression was normalized, with (4 %) M. oleifera leaf extract supplemented diet exhibiting stronger effects. These results suggest the protective and therapeutic roles of M. oleifera as a feed supplement in Labeo rohita against arsenic induced toxicity.

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.

Prevention policies for the marine ecological environment in the South China Sea as a consequence of excessive plastic compound use in Vietnam

Vietnam suffers from a distressing predicament: It ranks among the most heavily contaminated nations on earth. Its coastal and marine domains are plagued by an excess of plastic waste. Vietnam has consistently discharged a substantial amount of waste into the oceans, ranging from 0.28 to 0.73 million metric tons annually. Numerous areas have emerged as focal points of plastic pollution throughout its extensive seashore and marine areas. The escalating presence of marine litter poses an increasingly grave threat to the intricate equilibrium of Vietnam's marine ecosystems. This comprehensive policy study reveals that the mounting problem of ocean plastic pollution, characterized by the abundance of floating plastic debris, imperils both plant and animal life, placing various marine species such as seabirds, fish, turtles, and cetaceans at risk. The consumption of minuscule plastic particles and the harmful impact of chemical pollutants from plastic waste in the ocean not only endangers the vitality of marine life but also poses a substantial hazard to human well-being because plastic waste infiltrates the food chain. This research reveals that, despite the existence of numerous laws and policies-including the Law on Environmental Protection 2020, the Marine Plastic Waste Management Initiative for the Fisheries Sector 2020-2030, and the National Action Plan for Management of Marine Plastic Litter-a significant amount of plastic waste is infiltrating the river network and eventually infiltrating oceans as a result of improper monitoring and ineffective enforcement of these legislations. Relying primarily on existing data released by the government and other sources and a wide range of gray literature retrieved from reputable databases, this study aims to evaluate the role of Vietnam's legal framework for combating the critical issue of marine plastic pollution in the South China Sea. Integr Environ Assess Manag 2024;20:2088-2106. © 2024 SETAC.

Amino-modified nanoplastics at predicted environmental concentrations cause transgenerational toxicity through activating germline EGF signal in Caenorhabditis elegans

In the real environment, some chemical functional groups are unavoidably combined on the nanoplastic surface. Reportedly, amino-modified polystyrene nanoparticles (PS-A NPs) exposure in parents can induce severe transgenerational toxicity, but the underlying molecular mechanisms remain largely unclear. Using Caenorhabditis elegans as the animal model, this study was performed to investigate the role of germline epidermal growth factor (EGF) signal on modulating PS-A NPs' transgenerational toxicity. As a result, 1-10 μg/L PS-A NPs exposure transgenerationally enhanced germline EGF ligand/LIN-3 and NSH-1 levels. Germline RNAi of lin-3 and nsh-1 was resistant against PS-A NPs' transgenerational toxicity, implying the involvement of EGF ligand activation in inducing PS-A NPs' transgenerational toxicity. Furthermore, LIN-3 overexpression transgenerationally enhanced EGF receptor/LET-23 expression in the progeny, and let-23 RNAi in F1-generation notably suppressed PS-A NPs' transgenerational toxicity in the exposed worms overexpressing germline LIN-3 at P0 generation. Finally, LET-23 functioned in neurons and intestine for regulating PS-A NPs' transgenerational toxicity. LET-23 acted at the upstream DAF-16/FOXO within the intestine in response to PS-A NPs' transgenerational toxicity. In neurons, LET-23 functioned at the upstream of DAF-7/DBL-1, ligands of TGF-β signals, to mediate PS-A NPs' transgenerational toxicity. Briefly, this work revealed the exposure risk of PS-A NPs' transgenerational toxicity, which was regulated through activating germline EGF signal in organisms.