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Microplastics are emerging as prominent pollutants across the globe. Oceans are becoming major sinks for these pollutants, and their presence is widespread in coastal regions, oceanic surface waters, water column, and sediments. Studies have revealed that microplastics cause serious threats to the marine ecosystem as well as human beings. In the past few years, many research efforts have focused on studying different aspects relating to microplastic pollution of the oceans. This review summarizes sources, migration routes, and ill effects of marine microplastic pollution along with various conventional as well as advanced methods for microplastics analysis and control. However, various knowledge gaps in detection and analysis require attention in order to understand the sources and transport of microplastics, which is critical to deploying mitigation strategies at appropriate locations. Advanced removal methods and an integrated approach are necessary, including government policies and stringent regulations to control the release of plastics. [ABSTRACT FROM AUTHOR]

Long non-coding RNA maternally expressed gene 3 (MEG3) has been revealed to be involved in telomere length (TL) maintenance and homeostasis. However, it is unknown whether single-nucleotide polymorphisms (SNPs) in MEG3 could regulate TL in populations exposed to polycyclic aromatic hydrocarbons (PAHs). This study aimed to explore the effect of MEG3 genetic polymorphisms on TL in PAH-exposed populations. This study recruited 544 coke oven workers and 238 controls using random cluster sampling. The concentrations of four urinary OH-PAHs were measured by employing high-performance liquid chromatography. TL was measured by a quantitative polymerase chain reaction assay. The MEG3 genetic polymorphisms were detected using a Sequenom MassARRAY matrix-assisted laser desorption/ionization-time of flight mass spectrometry platform. The concentrations of four urinary OH-PAHs in the exposure group were significantly higher than those in the control group (P < 0.001). TL in the exposure group (4.57 ± 0.84) was significantly lower than in the control (5.00 ± 0.75), and TL had a negative correlation with OH-PAHs. The generalized linear model found that PAH exposure [β(95% CI) = −0.409(−0.537, −0.282), P < 0.001] and the CT+TT genotype in MEG3 rs10132552 [β(95% CI) = −0.299(−0.582, −0.017), P = 0.038] were associated with the decreased TL. In conclusion, PAH exposure and the CT+TT genotype in MEG3 rs10132552 may be the risk factors for TL reduction. [ABSTRACT FROM AUTHOR]

Soil and water are two important basic ecosystems for the survival of different organisms. The excessive microplastic pollutants in soil have been directly discharged into the terrestrial ecosystems. Microplastic pollutants (MPs) constitute a ubiquitous global menace due to their durability, flexibility, and tough nature. MPs posed threat to the sustainability of the ecosystem due to their small size and easy transportation via ecological series resulting in the accumulation of MPs in aquatic and terrestrial ecosystems. After being emitted into the terrestrial ecosystem, the MPs might be aged by oxidative degeneration (photo/thermal), reprecipitation (bioturbation), and hetero-accumulation. The mechanism of adsorption, degradation, and breakdown of MPs into unaffected plastic debris is accomplished by using several biological, physical, and chemical strategies. This review presents the importance of ecosystems, occurrence and sources of MPs, its toxicity, and the alteration in the ecology of the ecosystems. The inhibitory impact of MPs on the ecosystems also documents to unveil the ecological hazards of MPs. Further research is required to study the immobilization and recovery efficiency of MPs on a larger scale. [ABSTRACT FROM AUTHOR]

The combustion of cooking fuels generates detrimental gases significantly impacting human health, particularly for vulnerable populations like expectant mothers. Prenatal exposure of such hazardous emissions raises the probability of adverse pregnancy outcomes, including preterm birth (PTB) and low birth weight (LBW). Our research aims to explore the association between cooking fuel utilization and adverse birth outcomes in rural Ma'anshan, Anhui Province. A prospective cohort study was executed, employing the Maternal and Infant Health Assessment questionnaire to classify fuels into clean (natural gas, electricity) and polluting energy sources (coal, coal gas, firewood). Multivariate logistic regression models were conducted to evaluate the association between fuel consumption and postpartum maternal and infant outcomes. Among the 442 surveyed pregnant women, 38.2% (N=169) utilized polluting fuels. After adjusting for covariates such as age and BMI, the relative risks of preterm birth, low birth weight, and postpartum hemorrhage in the polluting fuel group compared to the clean fuel group were OR: 3.27, 95% CI: 1.34, 8.00; OR: 3.50, 95% CI: 1.12, 10.90; and OR: 3.18, 95% CI: 1.06, 9.46, respectively. These results indicate that the usage of polluting fuels during pregnancy may heighten the risk of adverse birth outcomes. Consequently, additional research is advised to mitigate the harmful emissions generated by cooking fuels and advocate for clean energy adoption, enhancing maternal and infant well-being. [ABSTRACT FROM AUTHOR]

As an important source of microplastics, the water ecological risk of tire wear particles (TWPs) has attracted widespread attention worldwide. However, the occurrence and behavior of TWPs and their biological effects in water environments have not been clearly analyzed. For example, most contemporary studies have focused on the evaluation of the aquatic toxicity of TWPs leachate, and little attention has been paid to the behavior process and potential risks of its surface properties in water environments. In addition, most studies rely on preparing TWPs under laboratory conditions or purchasing commercial TWPs for studying their water environmental behavior or exposure. These obviously cannot meet the requirements of accurate assessment of water ecological risks of TWPs. As thus, in addition to describing the occurrence, distribution, and (aging) transformation of TWPs in different water environments, we further tried to explain the potential water environment behavior process and multiple pathways leading to potential adverse impacts of TWPs on aquatic organisms from the perspectives of particle self-toxicity and release toxicity, as well as synergistic effects of TWPs and other substances are also discussed. The existing data, such as studies on the self-characteristics of TWPs, environmental factors, and subjects, are insufficient to comprehensively evaluate the recent changes in essential water ecosystem services and multifunctions caused by TWPs, implying that the impact of TWPs on water environmental health needs to be further evaluated, and the corresponding countermeasures should be recommended. In this context, the current review provides an outlook on future research on TWPs in aquatic environments. [ABSTRACT FROM AUTHOR]

The pollution of microplastics (MPs) is a worldwide major concern, as they have become a major part of our food chain. MPs enter our ecosystem via different pathways, including anthropogenic activities and improper disposal of plastics. The aim of this article is to review the current scientific literature related to MPs and how they affect different life forms on earth. Briefly, MPs induced negative effects on humans are primarily linked with the oxidative stress and disruption in immunity. MPs not only affect the soil chemical and physical properties such as reduction in soil health and productivity but also impose harmful effects on soil microorganisms. Moreover, MP-induced plant growth reduction results from three complementary mechanisms: (i) reduction in root and shoot growth, (ii) reduction in photosynthesis accompanied by higher reactive oxygen species (ROS) production, and (iii) reduction in nutrient uptake via altered root growth. Given the negative effects of MPs on different life forms, it is important to remove or remediate them. We have discussed different MP removal methods including coagulation, membrane filtration technology, biochar, and biological degradation of MPs in soil and wastewater effluents. The use of ozone as ultrafiltration technique has also been shown as the most promising technique for MP removal. Finally, some future research recommendations are also put forward at the end to further enhance our understanding of the MPs induced negative effects on different life forms. The flowchart shows the interaction of MPs from water contaminated with MPs with different parts of the ecosystem and final interaction with human health [ABSTRACT FROM AUTHOR]

Microplastics (MPs) represent a serious problem for the environment and for this reason they have been studied in many articles, especially their presence in aquatic environments and soils. MPs have been found in wastewater and sewage sludge from municipal wastewater treatment plants (WWTPs). Most part of the published works have focused on the detection and elimination of MPs in the water line and several reviews have been published in the last years. In addition, the application of sewage sludge produced from WWTPs for agricultural use is known to be a primary source of MPs in soils. However, in the scientific literature less attention has been paid to the sludge and little is known about MPs fate when it is applied in agriculture. This work aims to give a global revision on the most used techniques to identify and detect MPs in sludges, their characteristics and incidence, their effect on sludge treatments and their impact on the environment. As far as we know, there are no standardized protocols for MPs extraction from soil and the possible repercussions on the cultivation of plants are not known. This review evidences that more studies are necessary to stablished standardized protocols and decipher the main mechanisms and the effects of MPs from sewage sludge in the environment. [ABSTRACT FROM AUTHOR]

Microplastics (MPs) are increasingly being studied because they have become ubiquitous in aquatic and terrestrial environments. However, little is known about the negative effects of co-contamination by polypropylene microplastic (PP MPs) and heavy metal mixtures on terrestrial environment and biota. This study assessed the adverse effects of co-exposure to PP MPs and heavy metal mixture (Cu2+, Cr6+, and Zn2+) on soil quality and the earthworm Eisenia fetida. Soil samples were collected in the Dong Cao catchment, near Hanoi, Vietnam, and analyzed for changes in extracellular enzyme activity and carbon, nitrogen, and phosphorus availability in the soil. We determined the survival rate of earthworms Eisenia fetida that had ingested MPs and two doses of heavy metals (the environmental level — 1 × — and its double — 2 ×). Earthworm ingestion rates were not significantly impacted by the exposure conditions, but the mortality rate for the 2 × exposure conditions was 100%. Metal-associated PP MPs stimulated the activities of β-glucosidase, β-N-acetyl glucosaminidase, and phosphatase enzymes in soil. Principle component analysis showed that these enzymes were positively correlated with Cu2+ and Cr6+ concentrations, but negatively correlated with microbial activity. Zn2+ showed no correlation with soil extracellular enzyme activity or soil microbial activity. Our results showed that co-exposure of earthworms to MPs and heavy metals had no impact on soil nitrogen and phosphorus but caused a decrease in total soil carbon content, with a possible associated risk of increased CO2 emissions. [ABSTRACT FROM AUTHOR]

Microplastics (MPs) are widespread pollutants of emerging concern, and the risks associated with their ingestion have been reported in many organisms. Terrestrial environments can be contaminated with MPs, and terrestrial organisms, including arthropods, are predisposed to the risk of ingesting MPs. In the current study, the larvae of the paper wasp Polistes satan were fed two different doses (6 mg or 16 mg at once) of polystyrene MPs (1.43 mm maximum length), and the effects of these treatments on immature development and survival till adult emergence were studied. Ingestion of the two doses resulted in mortality due to impaired defecation prior to pupation. The survival of larvae that ingested 16 mg of MPs was significantly lower than that of the control. The ingestion of 16 mg of MPs also reduced the adult emergence (11.4%) in comparison to the control (44.4%). MPs were not transferred from the larvae to the adults that survived. These findings demonstrate that MP ingestion can be detrimental to P. satan, e.g. larval mortality can decrease colony productivity and thus the worker force, and that MPs can potentially affect natural enemies that occur in crops, such as predatory social wasps. [ABSTRACT FROM AUTHOR]

Hiking and trail running are a source of microplastic (MP) pollution on recreational trails in wilderness and conservation areas; however, the fate of MPs deposited on trails is poorly understood as MP mobility on such surfaces has not yet been examined. In this study, we simulated heavy rainfall (100 mm/h) on trail surfaces with existing MP pollution (in situ MPs) and spiked with 99 ± 2 rubber MPs (100–940 μm). Runoff was collected for 15 min and spiked and in situ MPs were quantified. Hydrological, erosional and microplastic responses were evaluated in relation to slope, bulk density, soil moisture and surface condition indicators, including amounts and types of surface cover and soil physical attributes. The MPs were largely immobile, with 85–100% of spiked MPs retained on trail surfaces. In situ MPs were detected in the trail runoff, with the majority being polyurethane, polypropylene and polyester. Microplastic movement was primarily influenced by hydrological effects, and analysis indicated the main explanatory variable was total runoff volume, followed by soil slaking. Trail sections with at least 15% herbaceous cover or a layer of loose alluvium had higher MP retention. Areas of resource accrual may be preferentially enriched, suggesting MPs from outdoor recreation may be concentrated on and adjacent to recreational trails. Microplastics deposited on trails may have long term implications for biodiversity and ecosystem functioning in wilderness and conservation areas, particularly around the trail corridor. [ABSTRACT FROM AUTHOR]

The unfavorable effects of environmental pollutants are becoming increasingly evident. In recent years, Caenorhabditis elegans (C. elegans) has been used as a powerful terrestrial model organism for environmental toxicity studies owing to its various advantages, including ease of culture, short lifespan, small size, transparent body, and well-characterized genome. In vivo bioassays and field studies can analyze and evaluate various toxic effects of the toxicants on the model organism, while emerging technologies allow profound insights into molecular disturbances underlying the observed phenotypes. In this review, we discuss the applications of C. elegans as a model organism in environmental toxicity studies and delineate apical assays such as lifespan, growth rate, reproduction, and locomotion, which are widely used in toxicity evaluation. In addition to phenotype assays, a comprehensive understanding of the toxic mode of action and mechanism can be achieved through a highly sensitive multi-omics approach, including the expression levels of genes and endogenous metabolites. Recent studies on environmental toxicity using these approaches have been summarized. This review highlights the practicality and advantages of C. elegans in evaluating the toxicity of environmental pollutants and presents the findings of recent toxicity studies performed using this model organism. Finally, we propose crucial technical considerations to escalate the appropriate use of C. elegans in examining the toxic effects of environmental pollutants. [ABSTRACT FROM AUTHOR]

There is increasing concern regarding airborne microplastics, but to date, studies have typically used coarse interval sampling (a day or longer) to generate deposition and concentration estimates. In this proof-of-concept study, we used a Burkard volumetric spore trap (intake 10 L min−1; recording airborne particulates onto an adhesive-coated tape moving at 2 mm hr−1) to assess whether this approach has potential to record airborne microplastics at an hourly resolution, thereby providing detailed diurnal patterns. Simultaneous sampling at outdoor and indoor locations at rural and urban sites showed clear daily and weekly patterns in microplastic concentrations which may be related to people and vehicle movement. Indoor residential concentrations of suspected microplastics were the highest (reaching hourly concentrations of 40–50 m−3), whilst rural outdoor concentrations were very low (typically 1–2 m−3 h−1). Whilst the approach shows great potential for high resolution data generation, further development is required for spectroscopic analysis and hence chemical confirmation of visual microplastic identification. [ABSTRACT FROM AUTHOR]

Microplastics are the new emerging pollutants ubiquitously detectable in aquatic and terrestrial ecosystems. Fate and behavior, as well as ecotoxicity, are of increasing environmental concern, particularly in sediments and soils as natural sinks. For a global environmental risk assessment, reliable and easy to apply analytical methods are mandatory to obtain comparable data. This is based on the isolation of microplastics out of the solid sample matrices prior to instrumental detection. Thus, this study provides an easy to apply approach for density separation. The technique emerged from a comparative study using different salt solutions to isolate conventional, and for the first time biodegradable, microplastics from different solid sample matrices, i.e., sand, artificial soil, and compost. Four solutions (water, sodium chloride, sodium hexametaphosphate, and sodium bromide) of different densities were applied followed by oxidizing digestion. Finally, the impact of the procedures on size and surface properties of microplastics was tested. Dependent on the sample matrix, the highest recovery rates of 87.3–100.3% for conventional polymers, and 38.2–78.2% for biodegradable polymers, were determined with sodium bromide. It could be shown that the type of solid sample matrix influences the recovery rates and has to be considered when choosing a sample preparation technique. [ABSTRACT FROM AUTHOR]

Since the year 2020, the use of plastic as a strategy to mitigate the spread of COVID-19 disease has been given substantial attention. Global environmental contamination of plastic creates waste and is a known threat to soil ecosystems as a main sink of microplastics. However, there is still considerable uncertainty about microplastics controlling soil properties alteration. Therefore, we carried out an incubation experiment with soil and Carex stenophylla Wahlenb., which are the dominant soil and grass species in semi-arid regions. We investigated the effect of polymer polyethylene terephthalate (PET) concentrations (0%, 1%, 3%, and 5%) on C. stenophylla growth and soil ammonium-N and nitrate–N, organic matter content, pH, soil aggregates, and soil respiration. When soils were exposed to PET microplastics, fewer seeds germinated (62.8 ± 32%) but not significantly (p value > 0.05) when soils were treated to 0, 1, 3, and 0.5% PET. Shoot height was also not effectively reduced with PET. The soil pH was considerably lower when exposed to higher PET compared to all other treatments with the soil exposed to 5% w/w PET for both unplanted and planted, being 0.84 and 0.54 units, respectively, lower than the controls. The soil microbial respiration under exposure to PET was considerably increased in comparison to control samples. Moreover, the presence of PET resulted in potential alterations of soil stability, and with PET present soil stability increased. In conclusion, PET microplastics cannot significantly affect the development of C. stenophylla but could affect crucial soil properties. In addition, changes occurred with increased variability in soil ammonium-N and nitrate–N, particularly at a high PET ratio. [ABSTRACT FROM AUTHOR]

Plastics have become inevitable for human beings in their daily life. Million tons of plastic waste is entering in oceans, soil, freshwater, and sediments. Invasion of plastics in different ecosystems is causing severe problems to inhabitants. Wild animals such as seabirds, fishes, crustaceans, and other invertebrates are mostly effected by plastic entanglements and organic pollutants absorbed and carried by plastics/microplastics. Plastics can also be potentially harmful to human beings and other mammals. Keeping in view the possible harms of plastics, some mitigation strategies must be adopted which may include the use of bioplastics and some natural polymers such as squid-ring teeth protein. This review focuses on the possible sources of intrusion and fate of plastics in different ecosystems, their potential deleterious effects on wildlife, and the measures that can be taken to minimize and avoid the plastic use. [ABSTRACT FROM AUTHOR]

Recently, the rapid development of digital finance in China has exerted a subtle influence on many aspects of social and economic development. However, the research on the impact of digital finance on corporate green innovation is rather lacking. In order to fill this gap, this paper uses the "Peking University Digital Finance Index" to evaluate the micro impact of financial innovation development on environmental governance from the firm level. The results show that digital finance can significantly improve the quantity and quality of corporate green innovation, and this effect still exists after considering endogeneity and a series of robustness tests. The promotion effect of digital finance on the quantity and quality of corporate green innovation is more obvious in state-owned, eastern, and mature enterprises. In addition, we find the mechanism behind the positive relationship between digital finance and corporate green innovation: digital finance makes firms more transparent and funds flow more convenient. Overall, this paper provides a micro explanation of environmental governance for the accelerated popularization of digital finance in emerging markets, which is urgently needed for most emerging economies seeking high-quality development. [ABSTRACT FROM AUTHOR]

The Red River is the largest river in northern Vietnam, and it serves as the main water source for production and human activities in the Red River Delta region. Cities and provinces located in the Red River Delta, for example, Hanoi, Nam Dinh, and Ha Nam, have experienced rapid economic growth with various large urban, industrial zones, and agricultural areas. As a result of urbanization and industrialization, surface water in this region has been contaminated by multiple anthropogenic sources. In this study, in addition to water quality assessment using WQI, we used the reflectance values of visible and near-infrared bands and in situ data to build a regression model for several water quality parameters. Among ten parameters examined, two parameters, including total suspended solids (TSS) and turbidity, were used to construct regression correlation models using the Sentinel-2 multispectral images. Our results can contribute useful information for comprehensive monitoring, evaluation, and management scheme of water quality in the Red River Delta. The application of this method can overcome the limitation of actual observation results that only reflect local contamination status and require a lot of sampling and laboratory efforts. [ABSTRACT FROM AUTHOR]

Plastic has become the most widespread human-made material and small fragments (< 5mm, so called microplastics, MPs) accumulate in all the ecosystems. It is now admitted that the terrestrial environment represents an important sink for MPs and it has only recently become the focus of research, notably in ecotoxicology. In spite of a growing body of evidence regarding the potential effects of MPs on soil biota, more efforts are needed to address issues in this field. The aim of our study was to measure, at different levels of biological organization, the responses of Cantareus aspersus snail to low-density polyethylene (LDPE) particles dispersed in their food. Juvenile snails were exposed to a range of LDPE concentrations (10, 25, and 50% v/v) and sizes (median particle size (d50) of 120, 292, 340, and 560 μm). This study showed no snail feeding avoidance toward LDPE. The ingestion and digestion processes along the snail digestive tract did not lead to a measurable fragmentation of the MP particles. At the individual scale, big sized particles improved growth at the lowest exposure concentration tested, whereas at the molecular level, only small sized particles triggered oxidative stress but without causing quantifiable cyto- or genotoxic effects. The underlying mechanisms remain to be elucidated which strengthens the necessity to improve our knowledge on the effects of MPs on various biological models to better evaluate their environmental risks in terrestrial environments. [ABSTRACT FROM AUTHOR]

The last decade increasing attention to litter accumulation in the marine environment revealed the issue of the terrestrial fluxes of plastic pollution into the oceans. However, limited studies investigate the macro-litter abundance and composition particularly in freshwater ecosystems and the adjusted coastal environment. In this study, we conducted an empirical analysis of anthropogenic litter (AL) in two freshwater streams and their estuaries of Lesvos island (Greece), strongly affected by the waste mismanagement in the Moria refugee camp. A total of 1,622 litter items were collected from five sites during the field campaign between the 3rd and 6th of June 2019. Among these, artificial polymer items (mainly drink bottles, single-use plastic bags, cutlery, and trays) irrespective of the site location constituted the major part ranging from 46 to 91% of total AL by mass. Drink bottles and plastic cutlery are found in higher percentage at Moria camp river and its estuary, while packaging and bag litter are more abundant at upstream sites. The operation of the camp has increased the AL abundance 13 times more than the reference site, causing severe threat to human health and to freshwater and marine environment. It is therefore important to improve the waste management system at (inter)national (change in production and packaging policy) and local scale (introducing sustainable solutions to refugee camp design) by promoting recycling and circular economy projects to diminish AL pollution. [ABSTRACT FROM AUTHOR]

The aim of this study was to characterize the physicochemical properties and microbial communities of particulate matter (PM) in Seoul, Korea. We collected long-term (2017–2019) precipitation samples and PM10 and PM2.5 monitoring data to determine the impact of soluble and insoluble chemical species on the soil surface. Ambient PM10 concentrations were higher than PM2.5 concentrations during the monitoring period, but both decreased during rainfall due to the washing effect of precipitation. PM2.5 particles had a "fluffy" shape and contained sulfur (0.2%), but suspended particles (SPs) contained many carbon particles (approximately 60%). Spherical particles containing metal oxides, Fe and Al, might be originated from coal combustion, wild fires, and metal-refining processes under high-temperature conditions. Dissolved ions in precipitation included those eluted from salts and coal combustion based on the correlation coefficients of Na and Cl (R = 0.953) and F and NO3 (R = 0.706). The δ15N–NO3 and δ34S–SO4 of precipitation were enriched as the atmospheric temperature decreased from 9.8 to −1.6°C, implying the influence of domestic coal combustion. Backward trajectories showed that, in winter, air parcels passed through industrialized cities from China to South Korea. The microbial communities associated with PM were strongly influenced by atmospheric conditions. Proteobacteria (range from 4.6 to 76.7%) and Firmicutes (range from 6.0 to 91.4%) were the most dominant phyla and were significantly affected by changes in the PM2.5 environment. The results indicate that the acidity of precipitation and the composition of aerosols were affected by fossil fuel combustion and mineral dust, and that atmospheric conditions may change as PM2.5 concentrations increase. [ABSTRACT FROM AUTHOR]

Microplastics (MPs) correspond to plastics between 0.1 μm and 5 mm in diameter, and these can be intentionally manufactured to be microscopic or generated from the fragmentation of larger plastics. Currently, MP contamination is a complicated subject due to its accumulation in the environment. They are a novel surface and a source of nutrients in soils because MPs can serve as a substrate for the colonization of microorganisms. Its presence in soil triggers physical (stability of aggregates, soil bulk density, and water dynamics), chemical (nutrients availability, organic matter, and pH), and biological changes (microbial activity and soil fauna). All these changes alter organic matter degradation and biogeochemical cycles such as the nitrogen (N) cycle, which is a key predictor of ecological stability and management in the terrestrial ecosystem. This review aims to explore how MPs affect the N cycle in the soil, the techniques to detect it in soil, and their effects on the physicochemical and biological parameters, emphasizing the impact on the main bacterial groups, genes, and enzymes associated with the different stages of the N cycle. [ABSTRACT FROM AUTHOR]

Elevated noise level is an emerging global problem. Therefore, the present work is conducted that can improve, increase, and integrate the already known issue in literature with new information coming from an emerging country such as Pakistan. The objectives of this study were (i) to assess the urban noise levels and traffic density of Chiniot and Jhang and (ii) to determine nonauditory health effects of noise levels on the residents of both cities. Noise levels were examined from 181 locations (103 from Jhang and 78 from Chiniot) and categorized into hospitals, educational, religious and recreational, residential, industrial areas, and traffic intersections. A-weighted noise level measurements were taken using an integrated sound level meter which recorded short-term road traffic noise continuously for 15 min at each location (LAeq15). The urban noise data showed 82% of the sites in Jhang (LAmax = 103 dB) and 95% in Chiniot (LAmax = 120 dB) exceeded the noise limits set by the National Environment Quality Standard of Pakistan (NEQS-Pak) and World Health Organization (WHO). Moreover, higher intensity of noise levels (LAeq15 ≥ 100 dB) was recorded in Chiniot (17 sites) than in Jhang (1 site). Regression analysis showed a relatively strong relationship of traffic density with noise at Chiniot (R2 = 0.48) compared to Jhang (R2 = 0.31). However, spatial variability of noise with traffic density was observed in both cities. Survey study revealed that all the respondents in Jhang and Chiniot suffered from many noise-related health problems such as annoyance (53 and 51%), depression (45 and 47%), dizziness (61 and 65%), headache (67 and 64%), hypertension (71 and 56%), hearing loss (53 and 56%), physiological stress (65 and 65%), sleeplessness (81 and 84%), and tinnitus (70 and 62%) due to noise, respectively. We conclude that noise levels are higher in Chiniot primarily due to high road traffic and secondarily due to high population density. It is recommended that vehicle maintenance and family and urban planning could be effective measures to reduce urban noise levels. [ABSTRACT FROM AUTHOR]

A possible source of microplastics has started to be released into nature because of the single-use face masks that protect us against the spread of COVID-19 and are being thrown onto the streets and into seas and nature. This study aims to estimate the amount of face mask use during the COVID-19 pandemic in Turkey, thereby expressing our concerns about waste management and plastic pollution and calling on appropriate solid waste management policies and governments to take the necessary measures to formulate their strategies at all levels. In this context, the number of masks in an area of 1 km2 in 3 different cities was determined theoretically and experimentally. Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscope (SEM) were also used to evaluate plastic polymer characteristics of the single-use face mask. It was determined that the three cities produce roughly 10 tons of face masks in a day. With the increasing use of single-use plastics, the impact of face masks on microplastic pollution is of great concern. Although studies on the recovery of disposable masks continue, the level is insufficient. Therefore, studies to be carried out on technologies that will enable the repeated use of masks are important. [ABSTRACT FROM AUTHOR]

Microplastic pollution in farmlands has become a source of major concern, but few previous studies have focused on the effect of microplastics on higher plants. In this study, the distribution of polystyrene nanoplastics (PSNPs) of four different particle sizes (100, 300, 500, and 700 nm) was investigated in cucumber plants, and their influence on physiological indexes of the root system and fruit quality was determined. The results showed that PSNPs initially accumulated in the root system before being transported to the aboveground parts of the plant. Finally, they were distributed in the leaves, flowers, and fruits, through the stems. The 300-nm plastic microspheres significantly increased root activity and malondialdehyde (MDA) and proline content of the roots. The results demonstrated that the environmental pressures caused by PSNPs of different particle sizes were different. The amount of soluble protein in cucumber fruits was significantly increased, and the levels of Mg, Ca, and Fe were significantly decreased by PSNPs of different particle sizes. Our findings provide a scientific basis for risk assessment of PSNP exposure in the soil–plant systems. [ABSTRACT FROM AUTHOR]

Microplastic pollution in cultivated soil has received increasing attention recently. There may be more serious microplastic abundance but little research has been done in cultivated soil in plateau areas. To survey the pollution characteristics of microplastics in inland cultivated soil, 100 soil samples collected from 10 counties of Yunnan Province were investigated through density separation and microscopic examination. The research results showed that microplastic abundance was in the range of 0.9 × 103 to 40.8 × 103 particles (kg Ds)−1 with average abundance of 9.8 × 103 particles (kg Ds)−1. Moreover, compared with other studies on sediments, it was found that microplastic abundance in inland soil was one order of magnitude higher than that in offshore sediments. The use of plastic mulch and its long-term residue in cultivated soil was an important reason for microplastic pollution. In this survey, various morphologies of microplastics existed, including fragment (78.3%), transparent/translucency (49.7%), and micro-size microplastics (< 500 μm) (89.3%). And the microplastic morphologies occurred in different degrees of aging phenomenon under the influence of the environment factors such as ultraviolet radiation. The findings provided the pollution status of microplastics in cultivated soil, and more attention should be paid to inland soil microplastic pollution. [ABSTRACT FROM AUTHOR]

Colony is a key to Microcystis becoming a dominant population and forming blooms. To find the mechanism of colony formation, we investigated cell wall structures of colonial and unicellular strains. Results showed that colonial strains had significant surface layer protein (S-layer) on the surface of cells than unicellular strains by transmission electron microscopy. Western blot showed colonial strains had more S-layer than the unicellular strains. When the S-layer gene (GenBank accession number CAO89090.1) of Microcystis aeruginosa PCC7806 was expressed in Synechocystis sp. PCC6803, PCC6803 aggregated into colonial morphology. The results indicated that the S-layer could promote colony formation in Microcystis. Based on the S-layer sequences of PCC6803 and PCC7806, nine S-layer genes in other Microcystis strains were screened from the GenBank. Sequence comparing showed that the S-layers conserved regions were all located in N-terminal. The S-layers contain repeats-in-toxin (RTX) sequences with Ca2+-binding site, and their amino acid composition, hydrophobicity, isoelectric point, etc. were consistent with the characteristics of RTX-type S-layer in bacteria. [ABSTRACT FROM AUTHOR]

Phytoplankton and bacterioplankton perform important ecological functions in lake ecosystem. In this paper, the abundance and composition of phytoplankton and bacterioplankton at 13 sites of Dianchi lake during the wet and dry seasons were monitored, and the relationship between phytoplankton and bacterioplankton in this plateau lake was studied. Phytoplankton community structure analysis was carried out by ocular method, and bacterioplankton was investigated by high-throughput 16S rRNA gene Illumina sequencing. The relationship between phytoplankton and bacterioplankton was observed using redundancy analysis. The results showed that 87 species of phytoplankton belonging to 5 phyla and 29 genera were identified in Dianchi lake. Phytoplankton diversity and richness were higher in the wet season than those in the dry season. In the wet season, Cyanophyta was the dominant phylum whose density was 2.01 × 108 cells/L, accounting for more than 90% of the total algae, then followed by Chlorophyta, Bacillariophyta, Chrysophyta, and Cryptophyta. The spatial distribution of phytoplankton in the wet season and dry seasons showed significant differences. In the dry season, the north-central part of Dianchi lake was dominated by Limnothrix redekei and Microcystis minutissima of Cyanophyta, while Pseudanabaena moniliformis and Coelosphaerium nagelianum of Cyanophyta mainly was dominated in the south of Dianchi lake. In the wet season, Microcystis minutissima of Cyanophyta was the dominant species all the area, while Limnothrix redekei of Cyanophyta was second dominant. Proteobacteria and Bacteroidetes were the dominant phyla among bacterioplankton. The community structure of bacterioplankton was influenced by Cyanophyta and Bacillariophyta. Cyanophyta had a major influence on Pseudomonas, Acinetobacter of Proteobacteria, and Flavobacterium of Bacteroidetes. Bacillariophyta showed a strong correlation with Gemmobacter, Stenotrophomonas, and Aeromonas of Proteobacteria. Cyanophyta and Bacillariophyta produced the most significant impact on predicted functional genes of bacterioplankton, and the predicted functional genes of the samples were different in different seasons. Cell densities of Cyanophyta were positively related to metabolism-predicted functional genes of bacterioplankton. Bacillariophyta and Cryptophyta had an impact on most of the cellular processes and signaling predicted functional genes. Bacterioplankton-predicted functional gene information storage and processing were significantly affected by cell densities of Chlorophyta. Therefore, the analysis of the phytoplankton community and the bacterioplankton-predicted functional gene in Dianchi lake exerts a great significance in revealing the ecosystem function of plateau lakes and harmful algal bloom control. [ABSTRACT FROM AUTHOR]

Concerns about the pollution of farmlands by microplastics and the associated toxicology have increased in recent times; however, studies on this topic are scarce. In this study, two kinds of PVC microplastics with different particle sizes (PVC-a with particle sizes from 100 nm to 18 μm, and PVC-b with particle sizes from 18 to 150 μm) and different content levels (0.5%, 1%, and 2%) were used to analyze the effects of PVC microplastics on the physiological characteristics of the lettuce root system and leaves. The results showed that PVC-a and PVC-b had no significant effect on the lettuce root activity. However, 0.5%a and 1%a significantly increased the total length, surface area, volume, and diameter of roots. In terms of leaves, PVC-a and PVC-b had no significant effect on the malondialdehyde content, but 1%a significantly increased the superoxide dismutase activity. Carotenoid synthesis was promoted by PVC-a but inhibited by PVC-b. Furthermore, 1%a could reduce the ability of light energy absorption, dissipation, capture, and electron transfer. The gray correlation analysis indicated that PVC-a correlated to a considerable degree with the indices related to photosynthesis, while PVC-b was significantly correlated with the indices related to root morphology. This study provides insights into the ecotoxicological effect of microplastics on farmland crops and associated ecological risk assessment. [ABSTRACT FROM AUTHOR]

Recharge of aquifers by urban stormwater may trigger significant ecological changes that can be detrimental to the biodiversity and functioning of groundwater ecosystems. Here, the effects of aquifer recharge (AR) on three levels of parameters were investigated: dissolved organic carbon (DOC) quantity and quality, global biofilm characteristics, and diversity changes of bacterial communities. As DOC enrichment by AR can be mitigated by vadose zone (VZ) thickness, three AR sites with thin VZ (< 3 m) and three sites with thick VZ (> 10 m) were selected. For each AR site, clay beads were incubated over a 10-day-long rainy period through wells in recharged and non-recharged groundwaters. Total proteins, dehydrogenase, and hydrolytic activities were monitored from clay beads to assess biofilm development. Bacterial richness on beads was estimated by 16S rRNA-based metabarcoding. AR was found to significantly increase DOC and biodegradable DOC (BDOC) concentrations, biofilm development, and bacterial richness especially in sites with thin VZ. VZ thickness was inversely related to microbial growth indicators and bacterial richness in groundwater, through a control of DOC availability. The proportion of Bacteroidetes 16S rRNA gene reads was higher in recharged groundwater than in non-recharged groundwater, suggesting that this phylum could be used as an indicator of DOC enrichment associated with AR. Quantitative PCR assays for Bacteroides DNA confirmed these trends and showed an enrichment of this bacterial group in DOC-rich aquifer waters. The positive linear relationships between BDOC concentrations and biofilm variables highlighted a strong C-limitation of groundwater impacting bacterial species sorting and activity. [ABSTRACT FROM AUTHOR]

The aim of the literature review was to describe the environments where the presence of airborne Staphylococcus aureus was confirmed and to catalogue the most often used methods and conditions of bioaerosol sampling to identify the bacteria. The basis for searching of studies on S. aureus in the bioaerosol in different environments was PubMed database resources from the years 1990–2019 (May). The review included studies which were carried on in selected environments: hospitals and other health care facilities, large-scale animal breeding, wastewater treatment plants, residential areas, educational institutions, and other public places. The highest concentrations and genetic diversity of identified S. aureus strains, including MRSA (methicillin-resistant S. aureus), have been shown in large-scale animal breeding. The role of the airborne transmission in dissemination of infection caused by these pathogens is empirically confirmed in environmental studies. Commonly available, well-described, and relatively inexpensive methods of sampling, identification, and subtyping guarantee a high reliability of results and allow to obtain fast and verifiable outcomes in environmental studies on air transmission routes of S. aureus strains. [ABSTRACT FROM AUTHOR]

Flood plains can make a significant contribution to food security due to their rich agricultural and aquaculture potentials but the misuse of pesticides in these ecosystems may seriously threaten their sustainability. We have assessed the risk of commonly used pesticides by rice and vegetable farmers on two major streams in the Ndop flood plain in Cameroon using the PRIMET model. Thirty pesticide formulations were identified containing 17 active ingredients belonging to fungicides (7), herbicides (3), and insecticides (7). Out of these, five posed acute and/or chronic risks to the streams. Chlorpyriphos-ethyl (ETR = 655), chlorothalonil (ETR = 250), and cypermethrin (ETR = 190) posed a definite acute risk to both streams. These pesticides also posed possible chronic risks with cypermethrin also posing a definite chronic risk (ETR = 1658) to fish in one of the streams. Mancozeb (ETR = 2.2) and λ-cyhalothrin (ETR = 2.8) posed a possible acute risk to both streams. It was interesting to note that most pesticides, including some of those that posed a risk, were applied at lower doses than their respective recommended doses. Differences in ETRs were also observed in the two streams with higher values occurring in the stream having a lower concentration of suspended solids. The higher velocity of the Ngwala-Mesaw stream did not affect the acute risk posed by pesticides. Pesticide toxicity was an important determinant in the risk posed and we recommend that appropriate mitigation measures be put in place to reduce the risk of these pesticides such as the implementation of an appropriate buffer zone between the edge of field and water body. [ABSTRACT FROM AUTHOR]

Microplastics (MPs) in natural environments have attracted lots of attention. Although the quantity of MPs present in terrene is much higher than that in aquatic environment, few studies have investigated the chemical behavior of MPs in terrestrial environment. This study investigate the Cu2+ (as a model heavy metal) adsorption capacity of six kinds of MPs (polyamide-6 (PA), polyethylene (PE), polystyrene (PS), polyethylene terephthalate (PET), polyvinyl chloride (PVC), polymethyl methacrylate (PMMA)) in batch adsorption experiments and the effects of different soil environmental factors, including pH and the presence of cations and low-molecular-weight organic acids (LMWOAs), as well as ultraviolet (UV) aging. The Cu2+ adsorption capacities of PA and PMMA were higher than those of other MPs and their maximum equilibrium adsorption capacities (estimated by the Langmuir adsorption equation) were 323.6 μg/g ± 38.2 and 41.03 ± 1.78 μg/g, respectively. The Cu2+ adsorption on MPs was affected by pH, and the greatest amount of Cu2+ adsorbed on PA and PMMA was observed at pH = 6 and pH = 7, respectively. The presence of Ca2+ or Mg2+ inhibited Cu2+ adsorption by MPs, due to competition for the adsorption sites. Moreover, Cu2+ adsorption by MPs was affected by various types of LMWOAs. The Cu2+ adsorption on PA was significantly reduced by citric acid, followed by oxalic acid, and oxalic acid was particularly evident for Cu2+ adsorption on PMMA. UV aging (200 h) had different effect on Cu2+ adsorption on MPs and it depends on the change of carbonyl index. Results demonstrate that soil environmental factors can change the ability of different MPs to adsorb Cu2+ and affect the transport of pollutants as carriers. [ABSTRACT FROM AUTHOR]

The main aims of the present research were (1) investigation of the temporal trends of atmospheric benzene concentrations in Tehran city during the period 2010 to 2013 and (2) assessment of carcinogenic and non-carcinogenic health risks of inhalation exposure to benzene. For the first objective, the data of ambient air benzene concentrations were derived from 15 air quality monitoring stations (AQMSs) in Tehran during the years 2010 to 2013 and they were temporally investigated after data cleaning and missing data imputation. The excess lifetime cancer risk (ELCR) and hazard quotient (HQ) were estimated to reveal the carcinogenic and non-carcinogenic health effects of exposure to ambient benzene. Our findings indicated that over 2010–2013, annual mean concentrations of benzene were in the range of 1.84 to 2.57 μg m−3, and the highest annual mean concentration was observed in 2011 with a mean of 2.57 μg m−3. The four-year average concentration of benzene during the period from 2010 to 2013 was 2.14 μg m−3. Furthermore, the HQ for inhalation exposure to ambient benzene was lower than the acceptable risk level (HQ < 1) over the study time period which indicated that the non-carcinogenic effects are very unlikely to happen. In addition, health risk assessment for ELCR showed that the potential cancer risk for inhalation exposure to benzene was 1.67 × 10−5 over the study period, which is significantly higher than the limits recommended by the U.S. EPA (1 × 10−6). Our study clearly proves that the ambient benzene concentration in Tehran has substantially higher carcinogenic effects on the population. Appropriate sustainable control measures should be taken to reduce air benzene concentration and protect public health. [ABSTRACT FROM AUTHOR]

Soils are both a sink and a pathway of plastic wastes, but there is a great lack of knowledge regarding their impacts on soil biota. To tackle the mechanisms of toxicity of these contaminants to soil invertebrates, earthworms (Eisenia fetida Savigny, 1826) were exposed during 28 days to different concentrations of low-density polyethylene microplastics (62, 125, 250, 500 and 1000 mg MPs kg−1 soildw) with sizes ranging between 250 and 1000 μm, in an artificial soil. The ecotoxicological responses were evaluated by analysing various oxidative stress biomarkers (catalase, glutathione S-transferase and thiobarbituric acid reactive substances), a biomarker of energy metabolism (lactate dehydrogenase) and overall organism molecular changes by Fourier transform infrared spectrometry (FTIR) and nuclear magnetic resonance (NMR) analyses. Significant effects resulting from an unbalanced oxidative stress system, expressed in terms of thiobarbituric acid reactive substances levels were recorded on earthworms exposed at the three highest concentrations tested. Despite that, no significant changes were recorded on the molecular profiles of earthworms by FTIR-ATR. NMR analysis pointed out for differences from the control, only for earthworms exposed to the lowest concentration of MPs. Considering that stress responses are complex, and involve multiple mechanisms, a cluster analysis taking into account all the parameters assessed, clearly identified two groups of earthworms separated by the concentration of 250 mg MPs kg−1 soildw, above each meaningful effects were recorded. [ABSTRACT FROM AUTHOR]

Plastic waste is a source of organic contaminants such as hexabromocyclododecanes (HBCDs). HBCDs have been found to cause developmental and reproductive toxicity; it is important to investigate the occurrence and metabolization of HBCDs in the soil environments with plastic waste contamination. This work analyzed HBCDs and their metabolites in soil and plant samples collected from Xinle and Dingzhou-the major plastic waste recycling centers in North China. Results showed that total HBCD concentrations in soils followed the order: plastic waste treatment site (11.0-624 ng/g) > roadside (2.96-85.4 ng/g) ≥ farmland (8.69-55.5 ng/g). HBCDs were detected in all the plant samples with total concentrations ranging from 3.47 to 23.4 ng/g. γ-HBCD was the dominant congener in soils, while α-HBCD was preferentially accumulated in plants. Compositions of HBCD isomers in soils and plants were significantly different ( P < 0.05) among sampling sites and among plant species. HBCDs in farmland soil and all plant samples exhibited high enantio-selectivity based on the enantiomeric fractions (EFs). Furthermore, metabolites of pentabromocyclododecenes (PBCDEs) were frequently identified in soils, and mono-OH-HBCDs were the most common ones in plants. This study for the first time provides evidences of HBCD contamination in the soil-plant system caused by plastic waste, their stereo-selectivity, and metabolization behavior, improving our understanding of the environmental behavior and fate of HBCDs. [ABSTRACT FROM AUTHOR]

Acute upper and lower respiratory infections are main causes of mortality and morbidity in children. Air pollution has been recognized as an important contributor to development and exacerbation of respiratory infections. However, few studies are available in China. In this study, we investigated the short-term effect of air pollution on hospital visits for acute upper and lower respiratory infections among children under 15 years in Ningbo, China. Poisson generalized models were used to estimate the associations between air pollution and hospital visits for acute upper and lower respiratory infections adjusted for temporal, seasonal, and meteorological effects. We found that four pollutants (PM, PM, NO, and SO) were significantly associated with hospital visits for acute upper and lower respiratory infections. The effect estimates for acute upper respiratory infections tended to be higher (PM ER = 3.46, 95% CI 2.18, 4.76; PM ER = 2.81, 95% CI 1.93, 3.69; NO ER = 11.27, 95% CI 8.70, 13.89; SO ER = 15.17, 95% CI 11.29, 19.19). Significant associations for gaseous pollutants (NO and SO) were observed after adjustment for particular matter. Stronger associations were observed among older children and in the cold period. Our study suggested that short-term exposure to outdoor air pollution was associated with hospital visits for acute upper and lower respiratory infections in Ningbo. [ABSTRACT FROM AUTHOR]

Atmospheric particulate matter (PM) is hypothesized to increase the risk of myocardial infarction (MI). However, the epidemiological evidence is inconsistent. We identified 33 studies with more than 4 million MI patients and applied meta-analysis and meta-regression to assess the available evidence. Twenty-five studies presented the effects of the PM level on hospitalization for MI patients, while eight studies showed the effects on mortality. An increase in PM was associated with hospitalization and mortality in myocardial infarction patients (RR per 10 μg/m = 1.011, 95 % CI 1.006-1.016; RR per 10 μg/m = 1.008, 95 % CI 1.004-1.012, respectively); PM also increased the risk of hospitalization and mortality in MI patients (RR per 10 μg/m = 1.024, 95 % CI 1.007-1.041 for hospitalization and RR per 10 μg/m = 1.012, 95 % CI 1.010-1.015 for mortality). The results of the cumulative meta-analysis indicated that PM and PM were associated with myocardial infarctionwith the addition of new studies each year. In conclusion, short-term exposure to high PM and PM levels revealed to increase risk of hospitalization and mortality for myocardial infarction. Policy support of pollution control and individual protection was strongly recommended. [ABSTRACT FROM AUTHOR]

An empirical approach is made in this investigation to predict the leached concentrations of sodium (Na), calcium (Ca), and potassium (K) in the effluents from a landfill site. Water at certain predetermined inflow filling rate is applied to a specific ponding depth, at the top of an experimental column filled with landfill refuse soil at the top (upper layer) and normal local soil at the bottom (base layer). The water infiltrates into the upper layer soil, percolates through the pores in upper and base layers, and in the process leaches the nutrients from the soils that are collected at the bottom of the column. The experimentations were for different combinations of heights of upper and base layer soils, water ponding depth, and inflow filling rates. The nutrient concentrations in the outflow leachates are measured using flame photometer. The observations showed mixed responses of leaching and trapping of nutrients in the soil layers for the various combinations. The experimental observations also inferred that the nutrient leaching is more for cases involving higher ponding depths and higher inflow filling rates. Empirical relationships with respect to the geometrical parameters, to predict the leached concentrations of Na, Ca, and K, are developed from the experimental observations using nonlinear least squares regressive techniques. Exponential equations gave the best empirical fit among various nonlinear relations in the regression technique. The empirical models also predicted well for each subcategory of independent variables that are substantiated by high correlation coefficients. [ABSTRACT FROM AUTHOR]

Two eddy covariance systems were installed in a high-severity burned zone (BZ) and an adjacent unburned (UNB) zone to monitor water vapour and carbon dioxide fluxes for 21 months (from June 2011 to February 2013) at a Spanish black pine forest affected by a stand-replacing wildfire and located in a mountainous area of central-eastern Spain. The differences between both sites were significant especially during the growing season, affecting gross primary productivity (GPP) more than ecosystem respiration (Reco). Net ecosystem exchange (NEE) for 2012 was −3.97 and 1.80 t C ha year for the unburned and burned sites, respectively, the GPP being 64 % lower for the BZ than the UNB zone. Evapotranspiration (ET) at the UNB was 18 % greater than at the BZ. Difference between sites was 160 mm during the whole studied period. This study reflects the effect of one of the major disturbances that can affect Mediterranean ecosystems, showing that carbon fluxes are more dramatically concerned than water vapour fluxes. [ABSTRACT FROM AUTHOR]

The article presents a study on management of contaminated sediments and associated risk in the particular case of organic and inorganic pollutants. It looks at the management options for polluted sediments, based on phytoremediation of contaminated sediments. In doing so it places emphasis on phytoextraction, phytostabilisation and phytoremediation of organic pollutants. Finally, it delves into microbial and mycorrhizal processes occurring in contaminated sediments during phytoremediation.

From June 1993 to October 1994, studies have been carried out on the effects of mercury in the Oder River and pike tissue contamination (muscle, kidney, liver). The mean mercury contents in the sediment range from 0.03 to 1.1 mg/kg dry weight. In the pike muscle, between 0.22 and 0.85 mg/kg, on a wet weight basis, were found. The measured mercury concentrations were analysed in relation to the number of macrophage centres of the liver, spleen and kidney of the pike. Positive correlations between mercury and MC response (0.54 ≤ r ≤ 0.79, p < 0.05) were found in all of these organs. The suitability of the macrophage-centre-response as a possible bioindicator for mercury pollution is discussed in the literature. In our study, the response of MCs was found to be suitable as a biomarker for the impairment of fish health. [ABSTRACT FROM AUTHOR]