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In this study, the potential of LaPO4 foam as a heterogeneous catalyst to produce biodiesel from highly acidic waste cooking oil (WCO) was investigated. The LaPO4 supported nickel foam was characterized by scanning electron microscopy (SEM), energy dispersive X-ray mapping analysis (EDX), X-ray diffraction, and Fourier transform infrared (FT-IR). In addition, the effect of different parameters such as the molar ratio of feedstock to methanol, contact time and the reaction temperature. Under the study conditions, with methanol to oil molar ratio of 5:1, and a reaction temperature of 90 °C, 91% FAME yield was obtained within 120 min with 2.5 wt % of LaPO4. The obtained results demonstrated that LaPO4 foam can be used effectively as a heterogeneous catalyst with superior catalytic efficiency (>90%) with easy separation and excellent stability.

Background Despite numerous studies regarding the prevalence of AFM1 in Milk, no systematic review and meta-analysis study on a global scale was conducted. Scope and approach In our study, the concentration and prevalence of aflatoxin M1 (AFM1) in different types of milk (cow, buffalo, goat, sheep, camel, donkey, and ewe) from 199 articles (320 data reports and samples of 51252) were meta-analysis using the random effect model (REM) based on countries, type of livestock and type of process milk (raw and pasteurized) subgroups. Key findings and conclusions The overall pooled AFM1 concentration in raw and pasteurized milk was (57.36 ng/l; 95%CI (55.65–59.64 ng/l)) and (85.39 ng/l; 95%CI (82.44–88.35 ng/l)), respectively. The lowest and highest concentration of AFM1 in raw milk was in Libya (1.58 ng/l; 95%CI (1.51–1.65 ng/l)) and Tunisia (14000.00 ng/l; 95%CI (13000.00–14005.00 ng/l)), respectively. The lowest and highest concentration of AFM1 in raw milk was in cow milk (79.65 ng/l; 95%CI (77.65–8.32 ng/l)) and Buffalo milk (2.35 ng/l; 95%CI (2.20–2.50 ng/l)), respectively. The lowest and highest concentration of AFM1 in Pasteurized milk was in Taiwan (3.00 ng/l; 95%CI (2.94–3.06 ng/l)) and Mexico (2801.48 ng/l; 95%CI (503.62–5099.35 ng/l)), respectively. The lowest and highest concentration of AFM1 in pasteurized milk was in the goat (7.67 ng/l; 95%CI (4.74–10.60 ng/l)) and cow (87.20 ng/l; 95%CI (90.19–97.54 ng/l)), respectively. Given that milk and dairy product consumption is a common dietary habit associated with health benefits, the incidence of AFM1 in milk and dairy products should be strictly monitored and controlled continuously. The amount of AFM1 in feedstuffs is an important factor in devising mechanisms to reduce AFM1 in milk and dairy products.

The COVID-19 pandemic has prompted all countries to adopt restraining measures to mitigate the spread of the disease. Usually, large-scale disasters tend to be accompanied by significant increases of psychological distress, depression and anxiety. Confinement measures imposed during the COVID-19 pandemic are likely to have similar consequences. In the present study we aim to evaluate how COVID-19 affected the overall psychological functioning of Portuguese individuals by providing a comparison of current data with status prior to the COVID-19 pandemic. The study sample was composed of 150 cognitively healthy participants. Results show an overall maintenance of cognitive capacities, although subjective cognitive decline complaints significantly increased during the pandemic. Regarding mental health, restraining measures culminated in an aggravation of depressive and decrease of the perceived quality of life, associated with feelings of loneliness and perceived social isolation. Finally, higher levels of pre-COVID-19 quality of life seem to play a protective role against depression and anxiety and predict less difficulties in emotion regulation, feelings of solitude and cognitive complaints. In sum, confinement due to COVID-19 implied an aggravation of the mental health of the Portuguese population, which appears to have been attenuated in those with higher pre-pandemic levels of perceived quality of life.

The widespread distribution of organic and inorganic pollutants in water resources have increased due to rapid industrialization. Rhizospheric zone-associated bacteria along with endophytic bacteria show a significant role in remediation of various pollutants. Metaomics technologies are gaining an advantage over traditional methods because of their capability to obtain detailed information on exclusive microbial communities in rhizosphere of the plant including the unculturable microorganisms. Transcriptomics, proteomics, and metabolomics are functional methodologies that help to reveal the mechanisms of plant-microbe interactions and their synergistic roles in remediation of pollutants. Intensive analysis of metaomics data can be useful to understand the interrelationships of various metabolic activities between plants and microbes. This review comprehensively discusses recent advances in omics applications made hitherto to understand the mechanisms of plant-microbe interactions during phytoremediation. It extends the delivery of the insightful information on plant-microbiomes communications with an emphasis on their genetic, biochemical, physical, metabolic, and environmental interactions.

Incense sticks ash is one of the most unexplored by-products generated at religious places and houses obtained after the combustion of incense sticks. Every year, tonnes of incense sticks ash is produced at religious places in India which are disposed of into the rivers and water bodies. The presence of heavy metals and high content of alkali metals challenges a potential threat to the living organism after the disposal in the river. The leaching of heavy metals and alkali metals may lead to water pollution. Besides this, incense sticks also have a high amount of calcium, silica, alumina, and ferrous along with traces of rutile and other oxides either in crystalline or amorphous phases. The incense sticks ash, heavy metals, and alkali metals can be extracted by water, mineral acids, and alkali. Ferrous can be extracted by magnetic separation, while calcium by HCl, alumina by sulfuric acid treatment, and silica by strong hydroxides like NaOH. The recovery of such elements by using acids and bases will eliminate their toxic heavy metals at the same time recovering major value-added minerals from it. Here, in the present research work, the effect on the elemental composition, morphology, crystallinity, and size of incense sticks ash particles was observed by extracting ferrous, followed by extraction of calcium by HCl and alumina by H2SO4 at 90–95 °C for 90 min. The final residue was treated with 4 M NaOH, in order to extract leachable silica at 90 °C for 90 min along with continuous stirring. The transformation of various minerals phases and microstructures of incense sticks ash (ISA) and other residues during ferrous, extraction, calcium, and alumina and silica extraction was studied using Fourier transform infrared (FTIR), dynamic light scattering (DLS), X-ray fluorescence (XRF), X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and inductively coupled plasma-optical emission spectroscopy (ICP-OES). DLS was used for analyzing the size during the experiments while FTIR helped in the confirmation of the formation of new products during the treatments. From the various instrumental analyses, it was found that the toxic metals present in the initial incense sticks ash got eliminated. Besides this, the major alkali metals, i.e., Ca and Mg, got reduced during these successive treatments. Initially, there were mainly irregular shaped, micron-sized particles that were dominant in the incense sticks ash particles. Besides this, there were plenty of carbon particles left unburned during combustion. In the final residue, nanosized flowers shaped along with cuboidal micron-sized particles were dominant. present in If, such sequential techniques will be applied by the industries based on recycling of incense sticks ash, then not only the solid waste pollution will be reduced but also numerous value-added minerals like ferrous, silica, alumina calcium oxides and carbonates can be recovered from such waste. The value-added minerals could act as an economical and sustainable source of adsorbent for wastewater treatment in future.

During the current COVID-19 pandemic, various forms of lockdown have been adopted, globally. This study evaluated the contamination changes (pre, post and during the lockdown) in the Yamuna River following the nationwide COVID-19 lockdown from 25 March–30 May (India). Samples of the surface water were taken from 9 sampling points to determine the physico-chemical, and biological concentration changes in surface water. The investigation showed the fluctuating results of the parameters. The peak saturation of physico-chemical parameters were observed prior to lockdown, followed by the post and during lockdown phases. The BOD and COD concentrations declined by 66% and 39.25%, respectively, compared to the pre-lockdown phase, while Faecal Coliform declined by over 40%. The improvement shown in this period indicates that it is possible for the Yamuna River to be cleaned up easily if people and the government come together.

Industrialization and modernization of agricultural systems contaminated lithosphere, hydrosphere, and biosphere of the Earth. Sustainable remediation of contamination is essential for environmental sustainability. Myco-remediation is proposed to be a green, economical, and efficient technology over conventional remediation technologies to combat escalating pollution problems at a global scale. Fungi can perform remediation of pollutants through several mechanisms like biosorption, precipitation, biotransformation, and sequestration. Myco-remediation significantly removes or degrades metal metals, persistent organic pollutants, and other emerging pollutants. The current review highlights the species-specific remediation potential, influencing factors, genetic and molecular control mechanism, applicability merits to enhance the bioremediation efficiency. Structure and composition of fungal cell wall is crucial for immobilization of toxic pollutants and a subtle change on fungal cell wall structure may significantly affect the immobilization efficiency. The utilization protocol and applicability of enzyme engineering and myco-nanotechnology to enhance the bioremediation efficiency of any potential fungus was proposed. It is advocated that the association of hyper-accumulator plants with plant growth-promoting fungi could help in an effective cleanup strategy for the alleviation of persistent soil pollutants. The functions, activity, and regulation of fungal enzymes in myco-remediation practices required further research to enhance the myco-remediation potential. Study of the biotransformation mechanisms and risk assessment of the products formed are required to minimize environmental pollution. Recent advancements in molecular "Omic techniques"and biotechnological tools can further upgrade myco-remediation efficiency in polluted soils and water.

The accumulation of heavy metals (HMs) in soil is presently a significant threat to the environment. The Cu, Mn, Zn, Cd, Pb, Ni, and Co concentrations were assessed in the agricultural soil samples. The results of various contamination indices including contamination factor, geo-accumulation indices, and ecological risk indices revealed that Cd is responsible for moderate to high contamination of soil. The multivariate statistical analyses including PCA, HCA, and correlation matrix suggested the mixed origin of HMs in the soil. Ingestion was found to be a primary route of exposure while dermal and inhalation exposure was negligible. Overall, the non-carcinogenic health risks were well within the safe limit to human health. However, healthwise, children were likely to be at greater risk compared with adults, due to their generally increased exposure to toxic agents through hand/mouth ingestion. Moreover, no carcinogenic risks were determined through the inhalation exposure of Cd, Ni, and Co.

Zinc plays a key role in plants growth and application of Zinc can, therefore, contribute to crop yield improvement. Nowadays, nanoparticles have received high attention because to their novel properties. The current work is done with an aim to investigate the biosynthesis of zinc oxide nanoparticles (ZnO NPs) and effect on fungus Rhizoctonia solani and on carrot crop. Use of nanoparticles as a nano-fertilizer requires an understanding of nanoparticles impact on crop plants We have used seed coat of almond for the synthesis of zinc oxide nanoparticles (ZnO NPs) characterized by EDS, FTIR, SEM and TEM. Spray with 50ppm and 100 ppm caused significant increase in plant growth parameter of carrot plants. It has been reported that the synthesized ZnO NPs demonstrated an inhibitory activity against plant pathogenic fungi R. solani. Antifungal efficiency of ZnONPs was further explained with help of Molecular docking analysis. Confirmation of the least binding energy was used to predict binding site of receptor with NPs to know mechanistic approach. ZnONPs are likely to interact with the pathogens by mechanical enfolding which may be one of the major toxicity actions against R. solani by ZnONPs.

Iron (Fe) and manganese (Mn) are harmful for human health, if present in a higher concentration, particularly in groundwater. The results of the study revealed that the concentration of Fe and Mn exceeded the WHO guideline for safe drinking water in 88 % and 74 % of groundwater samples, respectively. The non-carcinogenic health risk as assessed through computation of hazard quotient (HQ) due to intake of Fe and Mn contaminated groundwater was found much higher for children and adults. The values of HQ were recorded up to 1.96 for children and 1.52 for adult in case of Fe; and up to 2.13 for children and 1.61 for adult associated with Mn. On the basis of occurrence and spatial distribution of Fe and Mn in groundwater, the study area was delineated under high, elevated and low risk zone for priority attention.

The recent spread of severe acute respiratory syndrome coronavirus (SAR-CoV-2) and the accompanied coronavirus disease 2019 (COVID-19) has continued ceaselessly despite the implementations of popular measures, which include social distancing and outdoor face masking as recommended by the World Health Organization. Due to the unstable nature of the virus, leading to the emergence of new variants that are claimed to be more and rapidly transmissible, there is a need for further consideration of the alternative potential pathways of the virus transmissions to provide the needed and effective control measures. This review aims to address this important issue by examining the transmission pathways of SARS-CoV-2 via indirect contacts such as fomites and aerosols, extending to water, food, and other environmental compartments. This is essentially required to shed more light regarding the speculation of the virus spread through these media as the available information regarding this is fragmented in the literature. The existing state of the information on the presence and persistence of SARS-CoV-2 in water-food-environmental compartments is essential for cause-and-effect relationships of human interactions and environmental samples to safeguard the possible transmission and associated risks through these media. Furthermore, the integration of effective remedial measures previously used to tackle the viral outbreaks and pandemics, and the development of new sustainable measures targeting at monitoring and curbing the spread of SARS-CoV-2 were emphasized. This study concluded that alternative transmission pathways via human interactions with environmental samples should not be ignored due to the evolving of more infectious and transmissible SARS-CoV-2 variants., Graphical abstract Image 1

Nano-fibrillated cellulose (NFC) was extracted by a chemical method involving alkali and acid hydrolysis. The characterisation of the citrus sinensis fruit peel bran and nano-fibrillated cellulose was performed by XRD, FTIR, TEM, and FESEM. XRD confirmed the phase of NFC which showed monoclinic crystal with spherical to rod shape morphology with a size of 44&ndash, 50 nm. The crystallinity index of treated NFC increased from 39% to 75%. FTIR showed the removal of lignin and hemicellulose from waste peels due to the alkaline treatment. Silver nanoparticles were also synthesised by utilizing extract of citrus sinensis skins as a reducing agent. Pharmaceutical effluent samples from an industrial area were tested by Atomic Absorption Spectrometry. Out of the four metals obtained, cadmium and chromium were remediated by silver nanoparticles with nano-fibrillated cellulose via simulated method in 100 mg/L metal-salt concentrations over a time period of 160 min. The highest removal efficiency was found for cadmium, i.e., 83%, by using silver and NFC together as adsorbents. The second highest was for chromium, i.e., 47%, but by using only NFC. The Langmuir and Freundlich isotherms were well fitted for the sorption of Cd (II) and Cr (II) with suitable high R2 values during kinetic simulation. Thus, the isolation of NFC and synthesis of silver nanoparticles proved efficient for heavy metal sorption by the reuse of waste skins.

Metal tolerance is an important aspect for optimal production of edible plants for horticulture, cereals, spices, and medicinal and aromatic plants. Extravagant use of chemicals, fertilizers, and pesticides in agriculture along with contamination of irrigation water has made the soil and water resources unusable or highly contaminated with heavy metals. This chapter provides information in a nutshell on status and sources of metal contamination, role of metals in physiological and biological success of plants, and mechanistic part of metal toxicity (how metals inhibit different physiological processes in different plants) and further explains different mechanism prevailing to metal tolerance among different plant groups. Later a little information on molecular aspects of plants tolerance has also been highlighted. At current scenario, this information will be highly important to understand the specific role and significance of some metals in plant physiological processes and different mechanisms of removal of toxic metals as exclusion, avoidance, and tolerance for selecting or engineering specific metal toxicity-tolerant edible plant.

The present study describes the phytoremediation performance of water lettuce (Pistia stratiotes L.) for physicochemical pollutants elimination from paper mill effluent (PME). For this, pot (glass aquarium) experiments were conducted using 0% (BWW: borewell water), 25%, 50%, 75%, and 100% treatments of PME under natural day/light regime. Results of the experiments showed that the highest removal of pH (10.75%), electrical conductivity (EC: 63.82%), total dissolved solids (TDS: 71.20%) biological oxygen demand (BOD: 85.03%), chemical oxygen demand (COD: 80.46%), total Kjeldahl's nitrogen (TKN: 93.03%), phosphorus (P: 85.56%), sodium (Na: 91.89%), potassium (K: 84.04%), calcium (Ca: 84.75%), and magnesium (Mg: 83.62%), most probable number (MPN: 77.63%), and standard plate count (SPC: 74.43%) was noted in 75% treatment of PME after treatment by P. stratiotes. PCA showed the best vector length for TKN, Na, and Ca. The maximum plant growth parameters including, total fresh biomass (81.30 ± 0.28 g), chlorophyll content (3.67 ± 0.05 mg g-1 f.wt), and relative growth rate (0.0051 gg-1 d-1 ) was also measured in 75% PME treatment after phytoremediation experiments. The findings of this study make useful insight into the biological management of PME through plant-based pollutant eradication while leftover biomass may be used as a feedstock for low-cost bioenergy production. PRACTITIONER POINTS: Biological treatment of paper mill effluent using water lettuce is presented. Best reduction of physicochemical and microbiological pollutants was attained in 75% treatment. Maximum production of chlorophyll, plant biomass, and highest growth rate was also observed in 75% treatment.

In Hungary, successive steps have been taken toward adjusting GHG emissions from all sectors on a national scale. However, few studies were carried out to analyze the environmental dimensions of GHG emissions from an economic point of view. In this research, the contemporary changes of GHG emissions between 1985 and 2018 were analyzed using the Mann-Kendall test (M-K test); along with the interaction between GHG emissions and economic growth by applying the environmental Kuznets curve (EKC). Results showed that the industrial sector has been the main source of CO2-emitting, and contributed 72% of the total emissions. Meanwhile, the biggest CH4-emitting sector was the waste sector (44%), followed by the agricultural sector (39%). Nonetheless, the agricultural sector was responsible for more than 65% of N2O emissions over Hungary. The M-K test results showed that total CO2 emissions were reduced significantly (p

Coal fly ash (CFA) and coal-based incense sticks ash (ISA) have several similarities and differences due to the presence of coal as a common component in both of them. CFA are produced from the combustion of pulverized coal during electricity production in the thermal power plants while ISA are produced from the burning of incense sticks at religious places and at houses. A typical black colored Indian, incense sticks are mainly are comprised of coal powder or potassium nitrate, wood chip, fragrance, binder or binding agent, and bamboo sticks. The black colored incense sticks have coal powder or charcoal as a facilitator for smoother burning of incense sticks. The detailed investigation of CFA and ISA by X-ray fluorescence spectroscopy (XRF), electron diffraction spectroscopy (EDS), inductively coupled plasma-atomic emission spectroscopy (ICP-AES), Fourier transform-infrared (FTIR), X-ray diffraction (XRD), particle size analyzer (PSA), field emission scanning electron microscopy (FESEM), and transmission electron microscopy (TEM) revealed the morphological, chemical, and elemental properties. Both the coal based ashes comprises minerals like calcites, silicates, ferrous, alumina, and traces of Mg, Na, K, P, Ti, and numerous toxic heavy metals as confirmed by the XRF, ICP-AES, and EDS. While, microscopy revealed the presence of well-organized spherical shaped particles, namely cenospheres, plerospheres, and ferrospheres of size varying from 0.02 μm to 7 microns in CFA. Whereas, ISA particles are irregular, aggregated, calcium to carbon rich whose size varies from 60 nm to 9 microns and absence of well-organized spherical structures. The well developed and crystalline structure in CFA is due to the controlled combustion parameter in thermal power plants during the burning of coal while incense sticks (IS) burning is under uncontrolled manner. So, FTIR and XRD confirmed that the major portion of fly ash constitutes crystalline minerals whereas ISA have mainly amorphous phase minerals. CFA have ferrospheres of both rough and smooth surfaced, which was absent from the ISA and hence ferrous particles of CFA are of high magnetic strength. The detailed investigation of ashes will lead to the applications of ashes in new fields, which will minimize the solid waste pollution in the environment.

Understating of forest functioning is crucial for ensuring the sustainable flow of forest ecosystem services. Climate regulation service of a forest ecosystem can be ensured through emission reduction by increasing carbon sequestration in forests. However, understanding about the functioning of forests for carbon sequestration is constrained due to lack of information on nutrient stocks and stoichiometry of soils of forests of India. Present study focuses to examine the stoichiometry of major nutrients; nitrogen (N), phosphorus (P), carbon (C) of forest soil to understand the dynamics of the forests of Uttarakhand, India. The study also attempted to supplement the information about the soil carbon sequestration potential of important tree species of the forest. Soil samples were collected randomly for the evaluation of physico-chemical characteristics and stoichiometry of forest soil at four altitudinal ranges i.e., 2000 m a.s.l in the Himalayan region of Uttarakhand, India. The analysis shows that total nitrogen, total phosphorous, and soil organic carbon contents in forest soil were 0.35 ± 0.11%, 0.10 ± 0.04% and 3.36 ± 0.84%, respectively, which increases with altitude. The stoichiometric ratios viz., C:N:P, N:P, C:N, and C:P, and N:P were reported of 51.6:5.4:1, 4.30 ± 2.39, 9.60 ± 1.48, and 41.94 ± 23.35, respectively which were invariant with altitude. The low C:N ratio may be attributed to either increase in the nitrous oxide (N2O) emissions with an increase in nitrogen, or low in carbon stock leading to decrease in carbon dioxide (CO2) and methane (CH4) emissions. Moreover, the soil C sequestration potential in the forest tree species follow the order of Abies pindrow > Cedrus deodara > Quercus leucotrichophora > Pinus roxburghii. The information of the study would facilitate for broadening the understanding about the soil properties and stoichiometry of forest ecosystem and would provide an aid to forest management besides contributing to the mitigations strategies of the forests.

Phosphorus (P) is a vital nutrient for the ecosystems and its excess in wastewater streams leads to some environmental issues such as extensive algae growth (eutrophication). Phytoremediation is a green technology that is based on the combined actions of plants and their associated microbial groups to remove and transfer the toxic compounds in surface water, groundwater and soil. Aquatic plants are widely used for the remediation of contaminated rivers, eutrophic lakes, and other water bodies. In the past three decades, free-floating, submerged, emergent macrophytes and microalgae species have been used for P removal in aquatic plant-based systems such as constructed wetlands (CWs). This paper reviews the recent studies on the potential of aquatic plants such as free-floating, submerged, and emergent plants, and also microalgae for removal of P in different types of wastewaters. Several parameters such as plant species, hydraulic retention time, temperature, type of CWs, effluent concentration, and seasonal changes have effects on P removal. Based on the findings, some of the species such as Azolla and water hyacinth had the highest uptake ability up to 90% while algae species such as Chlorella showed about 70% of P removal. In addition, the mixed culture of aquatic plants can increase P removal if the interaction of the species is considered before cultivation in CWs.

Metal-organic frameworks (MOFs) have received great attention in a recent material sciences revolution. The present study was conducted to investigate the performance of two different synthesized MOFs for adsorption of a common synthetic endocrine-disrupter Bisphenol A (BPA) from the aquatic system. Highly crystalline MIL-53 and MOF (Ni) were synthesized with an specific surface area (SSA) of 11.39 m2/g and 21.71 m2/g, respectively. The adsorption efficacy of MIL-53 was about 8 times more than MOF (Ni). The effects of various operating parameters (i.e., pH, MOF dose, BPA concentration, and agitation time) for removal of bisphenol A (BPA) were investigated. BPA removal affected by study variables in the order of MOF dose > pH > BPA concentration > agitation time. In comparison with two-parameters models, three-parametric isotherm models showed a better description for BPA equilibrium data. Exploration of adsorption mechanism was supported by monolayer BPA adsorption theory. Adsorption was also favored at high BPA concentration and at room temperature. The maximum capacity (Qmax = 88.6 mg/g) of MIL-53 for adsorption of BPA was in a good match with the previous studies in which varieties of MOFs-based sorbents were applied. The current study showed promising results for the adsorption of BPA using MIL-53.

The present study assessed the phytoremediation efficiency of water fern (Azolla pinnata R.Br.) in the treatment of dairy wastewater (DWW). Batch mode experimentation was done using different dilutions (0 to 100%) of DWW transplanted with five healthy leaflets of A. pinnata. Besides this, the A. pinnata growth was captured using camera vision-based image recognition and further modeled using logistic and modified Gompertz models. The findings showed that after 14 days of phytoremediation experiments, the maximum significant (p 0.9533) and minimum difference between experimental and model-predicted results. Thus, the combined application of phytoremediation and image processing techniques can be used to monitor and maximize plant growth performance.

Today is the era of nanoscience and nanotechnology, which find applications in the field of medicine, electronics, and environmental remediation. Even though nanotechnology is in its emerging phase, it continues to provide solutions to numerous challenges. Nanotechnology and nanoparticles are found to be very effective because of their unique chemical and physical properties and high surface area, but their high cost is one of the major hurdles to its wider application. So, the synthesis of nanomaterials, especially 2D nanomaterials from industrial, agricultural, and other biological activities, could provide a cost-effective technique. The nanomaterials synthesized from such waste not only minimize pollution, but also provide an eco-friendly approach towards the utilization of the waste. In the present review work, emphasis has been given to the types of nanomaterials, different methods for the synthesis of 2D nanomaterials from the waste generated from industries, agriculture, and their application in electronics, medicine, and catalysis.

Chromium (Cr) is a trace element critical to human health and well-being. In the last few decades, its contamination, especially hexavalent chromium [Cr(VI)] form in both terrestrial and aquatic ecosystems, has amplified as a result of various anthropogenic activities. Chromium pollution is a significant environmental threat, severely impacting our environment and natural resources, especially water and soil. Excessive exposure could lead to higher levels of accumulation in human and animal tissues, leading to toxic and detrimental health effects. Several studies have shown that chromium is a toxic element that negatively affects plant metabolic activities, hampering crop growth and yield and reducing vegetable and grain quality. Thus, it must be monitored in water, soil, and crop production system. Various useful and practical remediation technologies have been emerging in regulating chromium in water, soil, and other resources. A sustainable remediation approach must be adopted to balance the environment and nature.

In the modern era, Gmelina arborea plantations are a hotspot of future research because of their high carbon sequestration potential. The present work was conducted during 2018 to 2020 on a young unmanaged Gmelina farm to understand the ecosystem’s carbon and its dynamics. The study area was categorized into three age classes: ≤ 5, 5–10, and 10–15 years. In a plantation, Gmelina trees (10%) were randomly selected while other trees (90%) were also taken into the consideration for ecosystem carbon. A stratified random nested quadrate sampling method was adopted for analyzing other vegetation forms under study. Overall, 51 individual species in the studied Gmelina farm were found which includes 23 tree species, 7 shrub species, 16 herbs, 2 climbers, and 3 species of ferns. The estimated quantitative vegetation parameters and diversity indices indicate that the plant assemblages were heterogeneous with native diverse species evenly distributed with fairly higher densities, frequencies, and abundance. Herbs were the most important species followed by shrubs and trees. Consequently, with the increasing age of plantation, the richness of plant species increased. Soil properties were significantly influenced by the age of the plantation but exhibited no discreet trend. Total biomass density and total carbon density increased with increasing plantation age while no drastic variation was found in available soil organic carbon (SOC) because of insignificant variability in litter production. Total carbon, available SOC (up to 60 cm depth) and ecosystem carbon in the three age class plantations fell in the ranges of 54.51–59.91, 48.18–55.73, and 104.81–110.77 Mg ha−1, respectively. The carbon sequestration potential of Gmelina arborea is higher compared to other reported species and highly supportive of converting unutilized agricultural landscapes to reduce the atmospheric carbon dioxide in future.

In recent times, the use of traditional herbal medicines in healthcare has declined, particularly amongst the rural population. This implies a risk of losing vital information from previous generations regarding plants and their use in traditional medicine. The objective of this study is to catalog the ways employed by inhabitants of the Garhwal Himalayas as part of their traditional approaches to healthcare. Information was gathered through snowball sampling using a questionnaire combined with informal interviews. This was supplemented by discussions with peers and practitioners prominent in this healing technique. The homogeneity within ethnomedicinal knowledge of these rural residents was tested using the informant consensus factor (Fic). The calculation of the fidelity value (FL) and the cultural importance index (CI) were made regarding the population’s dependency on plants. A total of 88 plant species from 44 families and 80 genera were identified as medicines for various complaints. Leaves were the most frequently used plant part followed by fruits, seeds, roots, bark, and flowers/buds. The largest number of taxa (15 species) were used for treatment of skin ailments (with Fic score of 0.85) followed by wounds, coughs, and digestive problems. There was a significant relationship observed between the medicinal plants used and distance (time of access) and family income. The present study will provide baseline information to be established for future research. The available information could help to discover new drugs for the pharmaceutical industry. Thus, the study revealed that the plants that have high scores of FL and CI can be used to discover new drug extraction in the future for further studies.

Coal fly ash is found to be one of the key pollutants worldwide due to its toxic heavy metal content. However, due to advancements in technology, coal fly ash has gained importance in various emerging fields. They are rich sources of carbonaceous particles which remain unburnt during burning of various coals in thermal power plants (TPPs). Various carbonaceous nanoparticles in the form of fullerenes, soot, and carbon nanotubes could be recovered from coal fly ash by applying trending techniques. Moreover, coal fly ash is comprised of rich sources of organic carbons such as polycyclic and polyaromatic hydrocarbons that are used in various industries for the development of carbon-derived value-added materials and nanocomposites. Here, we focus on all the types of carbon nanominerals from coal fly ash with the latest techniques applied. Moreover, we also emphasize the recovery of organic carbons in polyaromatic (PAHs) and polycyclic hydrocarbons (PCHs) from coal fly ash (CFA). Finally, we try to elucidate the latest applications of such carbon particle in the industry.

The present work integrates concentrations of potentially toxic elements (PTE) (i.e. As, Cd, Cr, Cu, Hg, Ni, Pb and Zn) from (i) environmental media (i.e. soil, crops) and (ii) human hair. The aim was to assess whether agricultural soil and vegetable quality are related to risks to human health from different exposures pathways and if there are any signs of it in human hair. Domestic vegetable gardens in the surroundings Estarreja chemical complex (ECC), Municipality of Estarreja, central Portugal, were the selected for the current study. Data analysis of two soil fractions (2 mm and 55 years old) showed that agricultural soil-dust ingestion induces a high-non-carcinogenic risk (HI) for As (HI up to 41 and 4.4, for children and adult, respectively), Pb (HI up to 2.5 for children) and Hg (HI up to 1.3 for children) and carcinogenic risk (CR) for As (10−3 for both age groups). Exposure through consumption of tomatoes and potatoes grown in the study soils does not present a high health hazard. However, exposure to As through consumption of cabbage presents both carcinogenic and non-carcinogenic health risks for both studied age groups (CR > 10−4 and HI > 1.1). It is likely that hair As and Hg concentrations increases in both children and adults can be related to the ingestion of agricultural soil and cabbage, and inhalation or dermal contact with contaminated soil. Nonetheless, this assumption requires further investigation, including on other potential sources of contaminants for the local population, such as dietary intake of other foodstuffs. Hair Cr content in the adult group of residents showed maximum values above the normal range for non-exposed individuals, as well as high mean and median values which may be related to the high Cr content in the studied foods. The exposure study results are in agreement with As and Hg concentrations in both children and adults hair and validate it as a biomarker of As and Hg local environmental exposure.

Despite the influence of other geological and geomorphological factors, chemical weathering at the Earth's surface is strongly controlled by climate. Thus, a measure of weathering intensity determined from soils or sediments should provide information about the climatic conditions associated with their formation. Available geochemical and mineralogical data on modern fluvial and marine muds from different regions of southern Africa and its Atlantic continental margin are used to review the links between sediment composition and climatic properties together with the possible causes of variance. Although river muds may not be generated exclusively in a single sedimentary cycle and erosion and weathering processes do not necessarily take place in a spatially homogeneous way, significant relationships between mineralogical and geochemical signatures of river mud and rainfall in the corresponding catchment area were recognised. Our study shows that the composition of clay is strongly influenced by climatically-driven weathering, whilst coarser mud fractions tend to be more affected by provenance, grain size, hydraulic sorting, and recycling. In the marine environment the climatic signal may be lost even in clay, because of hydraulic fractionation, authigenic mineral growth and mixing with foreign particles. Given the ubiquitous character of fluvial muds, and the easy and non-expensive methods available for separating and analysing clay fractions, their geochemical fingerprints represent a most precious source of information concerning climate. Any geochemical parameter used as a regional proxy of climate, however, still requires that the diversity of geological, geomorphological, and biological factors that affect its value are cautiously considered.