Radon quantification in water and dose estimation via inhalation and ingestion across age groups in the Pattan region of North Kashmir, India
Human survival hinges on access to water, which provides vital necessities. It is crucial to secure reliable, affordable, and uncontaminated water to maintain health and sustain life. For the potential impact of radioactive water pollution on human well-being, a scintillation-based smart RnDuo detector was employed in the Pattan region of North Kashmir Baramulla to quantify radon levels in diverse underground water. The dose contribution to various organs through inhalation and ingestion pathways has been analyzed. The study assesses the levels of radon in water, which varied from 19.88 to 74.37 Bq/L with an average of 37.65 Bq/L. All of the values were higher than the United States Environmental Protection Agency(USEPA) suggested guideline of 11 Bq/L but lower than the 100 Bq/L prescribed by the World Health Organization (WHO). The age group-wise inhalation and ingestion doses are higher than the 100 μSv/y recommended by WHO but within the prescribed range of 3-10 mSv/y as suggested by the International Commission on Radiological Protection (ICRP). Doses to various organs (lungs and stomach) are also calculated in the present study. The results of the present investigation will help to enhance the quality of the water and guide future epidemiological studies.
Effects of microplastics on 3,5-dichloroaniline adsorption, degradation, bioaccumulation and phytotoxicity in soil-chive systems
Microplastics (MPs) and pesticides are two pollutants of concern in agricultural soils. 3,5-dichloroaniline (3,5-DCA), a highly toxic metabolite of dicarboximide fungicides, commonly co-exists with MPs and poses a risk to the environment and food safety. Batch adsorption and soil incubation experiments were employed to investigate the effects of polyethylene (PE) and polylactic acid (PLA) MPs on the environmental behavior of 3,5-DCA in soil. Chive (Allium ascalonicum) was used as the experimental plant, a pot experiment was conducted to examine the effects of individual or combined exposure to MPs and 3,5-DCA on plant 3,5-DCA bioaccumulation, growth characteristics, and phytotoxicity. The results showed that PE- and PLA-MPs increased the adsorption capacity of soil to 3,5-DCA and prolonged the degradation half-life of 3,5-DCA by 6.24 and 16.07 d, respectively. Two MPs partially alleviated the negative effects of 3,5-DCA on the root length and fresh weight of chives, while PE-MPs had a positive and dose-dependent impact on the contents of photosynthetic pigment in chive leaves. Co-exposure to 3,5-DCA and MPs increased residues of 3,5-DCA in soil and chive roots but had no significant effect on 3,5-DCA residues in chive stems or leaves. Moreover, 3,5-DCA residues in PLA-MP soil were consistently higher than those in PE-MP soil. Conclusively, MPs altered the 3,5-DCA adsorption and degradation behavior in soil, as well as its bioaccumulation in chives. Co-exposure to MPs and 3,5-DCA had dose-dependent and MP-specific effects on chive plant development and phytotoxicity.
Environmental microplastic and phthalate esters co-contamination, interrelationships, co-toxicity and mechanisms. A review
Plastics have been pervasive in society for decades, causing extensive environmental contamination. The co-occurrence of microplastics (MPs) and phthalate esters (PAEs) in the environment has significant implications for the global population. This review focuses on the simultaneous presence of MPs and PAEs, exploring co-pollution, leaching, adsorption, correlation, and co-toxicity. Both MPs and PAEs are found in various environmental compartments, including water, sediments, aquatic organisms, pig feed, masks, gloves, and liquid waste from garbage infiltration. Factors such as time, temperature, UV light exposure, and the type of MPs can influence the leaching and adsorption of PAEs onto MPs. The correlation between MPs and PAEs allows for the use of PAEs as indicators for the presence of MPs. However, current constraints, like limited data availability and regional coverage, impede the feasibility of comprehensive tracking. Additionally, the combined effects of MPs and PAEs demonstrate synergistic toxicity, leading to adverse health effects such as reproductive toxicity, neurotoxicity, hepatotoxicity, nephrotoxicity, and other toxicities, primarily mediated by oxidative stress processes. Consequently, the findings provide valuable insights for future researchers and regulatory bodies, enabling the development of more effective strategies to address the simultaneous presence of microplastics and PAEs and mitigate their harmful impacts on human health.
Mercury in saliva, milk, and hair of nursing mothers in southeastern Iranian mothers: levels, distribution and risk assessment
This research is on lactating mothers in the city of Chah Bahar in Iran. This descriptive-analytical and questionnaire study selected a random sample of 80 mothers to examine mercury levels in their hair, milk, and saliva. The average concentration of mercury in milk, hair and saliva of mothers was 1.23 ± 0.48 µg/l, 1.81 ± 0.55 µg/g and 1.10 ± 0.63 µg/l, respectively. There was a significant correlation between mercury levels in mothers saliva and hair. Still, only a weak correlation was found between mercury levels in milk and hair, and milk and saliva, possibly associated with the high lipid content in milk. The number of children and length of the mother's pregnancy were related to the amount of mercury in the mother's milk. The number of teeth filled with amalgam, consumption of fish and marine products, consumption of fruit, and infant's weight at birth were also associated with the amount of mercury in breast milk. Chewing gum, fish consumption, infant's birth weight, weight, and length of pregnancy were among the factors associated with the amount of mercury in mothers' saliva. The mercury concentration in milk exceeded the WHO (1.4-1.7 µg/g) normal level in 8.5% mothers, and hair mercury was found in 12.5% mothers. It should be kept in mind that any amount of mercury can be harmful.
Risk assessment of uranium in water sources near coal mines and in human organs of Shahdol District, Madhya Pradesh, using biokinetic modelling
This study concentrated on determining the levels of uranium present in drinking water samples obtained from various locations throughout the Shahdol district in Madhya Pradesh, India. In this assessment a LED fluorimeter Quantalase (LF-2a) was utilized. Uranium, being a radioactive substance, can be hazardous to health when consumed in significant quantities over extended durations. The study found that the average uranium concentration was 167.91 µg/L. 82% of samples exceeded recommended limits, emphasizing the essential aspect of this study. The study utilizes the age-specific biokinetic model developed by the International Commission on Radiological Protection to examine uranium distribution across various organs. Using dosimetric model, the study provides a comprehensive health risk analysis by assessing the chemical toxicity and the radiation dosages received by particular organs. Longitudinal studies on uranium distribution across different organs and tissues showed that the kidneys, liver, non-exchangeable bone volume, and soft tissues are the primary locations where uranium accumulates.
Driving mechanisms of the spatial distribution of industrial parks and the relative hazard level of the surrounding environment
Analyzing the formation mechanisms of industrial parks and quantitatively evaluating the related hazard levels are important for understanding the development and planning of industrial parks, but there is currently a lack of relevant research. In this study, Beijing was taken as a case study. The analysis results showed that (1) the overall spatial distribution of industrial parks in Beijing followed a clustering pattern, with nested spatial distribution pattern, where larger structures contributed 53.96% of the variance; (2) for the overall spatial distribution of industrial parks, kernel density of enterprises was the main influencing factor, which there were synergistic enhancement effects with almost all other influencing factors, especially urban construction, the number of financial institutions, the population density, this can share transportation and other resources, achieving coordinated development. According to these main factors, the prediction model of the future spatial distribution pattern of industrial parks in Beijing was established; (3) for site selection of each industrial park, twenty-two industrial parks near industrial enterprises in Beijing were more affected by industrial enterprise clustering, and the remaining 65 industrial parks were strongly affected by terrain, (4) The industrial parks in the central and southern parts of Beijing presented a relatively high hazard level to the surrounding sensitive receptors. These results provide theoretical support for the development and layout of industrial parks.
Accumulation and risk assessment of heavy metals in different varieties of leafy vegetables
A pot experiment was conducted to investigate the differences in heavy metal accumulation in different varieties of leafy vegetables (five leafy vegetables four or five varieties of each) and their potential risk. The results revealed that the concentrations of Cd in all the vegetables exceeded the limit for China (0.2 mg/kg) and that the As and Pb concentrations were within the limit. The bioaccumulation of Pb, Cd, and As in spinach (0.01, 1.08, and 0.02) and rape seedlings (0.004, 0.43, and 0.03) were the highest and lowest, respectively. Health risk assessments indicate that the hazard index (HI) ranged from 0.66 to 3.37 and 2.86 to 14.64 for adults and children, respectively, and the total carcinogenic risk (TCR) ranged from 2.13E-03 to 1.86E-02 and 9.27E-03 to 8.07E-02. Probabilistic health risk assessment revealed that the HI was 3.06 and 4.75, and the TCR was 2.5E-03 and 8.88E-04 for adults and children, respectively. More importantly, heavy metal accumulation significantly differed among varieties of leafy vegetables, especially spinach. The BF of Pb, Cd, and As in spinach ranged from 0.003 to 0.01, 0.77 to 1.39, and 0.01 to 0.02, respectively. Geodetector analysis revealed that oxalic acid, available As, and organic matter are the key factors that affect Pb, Cd, and As accumulation, respectively, in these vegetables. These results suggest that the planting of suitable types and varieties of vegetables can reduce the potential health risk to a certain extent and that more effective measures should be implemented to ensure the safety of local residents in areas contaminated with heavy metals.
Assessment of radiological hazards in terms of gross α -β activities in groundwater in and around Beldih mine region of eastern India
In the present study, liquid scintillation counting triple to double coincidence ratio technique is used to ascertain the gross α and β activity in groundwater samples collected from the Beldih mine region in the vicinity of the South Purulia Shear Zone (SPSZ) of Chota Nagpur Plateau in eastern India. A total of sixty samples were collected from deep tube wells located in the study area to assess the potential health threats caused by α and β emitting radionuclides present in these water samples. Average gross α activity in the region of study is 0.09 ± 0.05 Bq/L, with a maximum of 3.22 ± 0.07 Bq/L. On the other hand, the average gross β activity is found to be 0.13 ± 0.02 Bq/L, with a maximum of 0.29 ± 0.02 Bq/L. It was observed that gross α activity level in three samples exceeds the safety limit of 0.5 Bq/L recommended by the World Health Organization. No significant gross β activity was observed. However, the radiological parameters for assessment of potential health threats due to ionizing radiation have been observed to be significantly high for adults. The results of this study indicate that the radiological assessment of groundwater in the Beldih mine region may be extended in future.
Soil nitrogen biogeochemistry and hydrological characteristics shape the nitrate levels in a river
The high levels of nitrate (NO) in the surface water have contributed to eutrophication and other eco-environmental damages worldwide. Although the excessive NO concentrations in rivers were often attributed to anthropogenic activities, some undisturbed or slightly disturbed rivers also had high NO levels. This study utilized multi-pronged approaches (i.e., river natural abundance isotopes, N-labeling techniques, and qPCR) to provide a comprehensive explanation of the reason for the high NO levels in a river draining forest-dominated terrene. The river natural abundance isotopes (δN/δO-NO) indicated that the soil source (i.e., soil organic nitrogen-SON and chemical fertilizer-CF) were the primary contributors to the NO, and the NO removal was probably prevalent in the basin scale. The N-labeling techniques quantitatively showed that denitrification and anammox were stronger than nitrification in the soils and sediments. Structural equation models suggested that nitrification in the soils was regulated by NH-N contents, which, in turn, were closely related to fertilization in spring. Denitrification and anammox were largely controlled by elevation and functional gene abundances (i.e., nirK and hzsB, respectively). The hydrological isotopes (i.e., δD/δO-HO) indicated that the transport of NO from soil to the river was related to the intensity of runoff leaching to the soil, In contrast, the riverine NH was largely from point sources; thus, increasing runoff led to a dilution effect. This study clearly showed that soil biogeochemistry and hydrological condition of a river basin jointly shaped the high NO levels in the almost undisturbed river.
Characterization of phosphorus storage and release fluxes at the sediment-water interface of lakes in typical agricultural and irrigation areas: a case study of Chagan Lake in western Jilin, China
Endogenous phosphorus release from sediments is a major cause of eutrophication in water bodies. To investigate the endogenous phosphorus morphological features and migration patterns in lakes under the influence of agricultural irrigation areas, we analyzed the changes of polymorphic phosphorus content in lake sediments under irrigation withdrawal conditions based on field sampling tests and sediment phosphorus release dynamics simulation experiments and used the diffusive flux method to determine the flux of phosphorus release from the sediment-water interface (SWI). The results showed that: (1) Data from encrypted sampling during the receding period revealed total phosphorus (TP) of lake water decreased from 0.11 mg/L to 0.05 mg/L, and TP of sediment increased from 723.53 mg/kg to 955.89 mg/kg. (2) The order of polymorphic phosphorus content of sediments at the lake inlet before the irrigation period was Fe-Al bound phosphorus (NaOH-nrP) > insoluble phosphorus > Fe-Al oxide bound phosphorus (NaOH-rP) > Calcium bound phosphorus (Ca-P) > Fe-Mn chelated phosphorus (BD-P) > active phosphorus. Interconversion between sedimentary polymorphic phosphorus is more drastic after the irrigation period. (3) The phosphorus forms extracted from sediments were ranked as insoluble phosphorus > NaOH-nrP > NaOH-rP > active phosphorus > Ca-P > BD-P. Insoluble phosphorus is the predominant form of phosphorus in sediments. (4) The TP exchange fluxes between the SWI by the diffusive flux method were 0.30 mg/(m2·h) and -0.33 mg/(m2·h) respectively. Receding water conditions promote sediment adsorption of TP from overlying water. The research findings establish a theoretical foundation for endogenous phosphorus from lake sediments in agricultural irrigation areas.
Machine learning-based identification of critical factors for cadmium accumulation in rice grains
The aggregation of Cadmium (Cd) in rice grains is a significant threat to human healthy. The complexity of the soil-rice system, with its numerous influencing parameters, highlights the need to identify the crucial factors responsible for Cd aggregation. This study uses machine learning (ML) modeling to predict Cd aggregation in rice grains and identify the influencing factors. Data from 474 data points from 77 published works were analyzed, and eight ML models were established using different algorithms. The input variables were total soil Cd concentration (TS Cd) and extractable Cd concentration (Ex-Cd), while rice Cd concentration (Cd) was the output variable. Among the models, the Extremely Randomized Trees (ERT) model performed the best (TS Cd: R = 0.825; Ex-Cd: R = 0.792), followed by Random Forest (TS Cd: R = 0.721; Ex-Cd: R = 0.719). The ERT feature importance ranking analysis revealed that the essential factors responsible for Cd aggregation are cation exchange capacity (CEC), TS Cd, Water Management Model (WMM), and pH for total soil Cd as input variables. For extractable Cd as an input variable, the vital factors are CEC, Ex-Cd, pH, and WMM. The study highlights the importance of the Water Management Model and its impact on Cd concentration in rice grains, which has been overlooked in previous research.Please check and confirm that the authors and their respective affiliations have been correctly identified and amend if necessary.The authors and their respective affiliations are correct.Author details: Kindly check and confirm whether the corresponding author is correctly identified.It is correct.
Mapping surface soil organic carbon density of cultivated land using machine learning in Zhengzhou
Research on soil organic carbon (SOC) is crucial for improving soil carbon sinks and achieving the "double-carbon" goal. This study introduces ten auxiliary variables based on the data from a 2021 land quality survey in Zhengzhou and a multi-objective regional geochemical survey. It uses geostatistical ordinary kriging (OK) interpolation, as well as classical machine learning (ML) models, including random forest (RF) and support vector machine (SVM), to map soil organic carbon density (SOCD) in the topsoil layer (0 - 20 cm) of cultivated land. It partitions the sampling data to assess the generalization capability of the machine learning models, with Zhongmu County designated as an independent test set (dataset2) and the remaining data as the training set (dataset1). The three models are trained using dataset1, and the trained machine learning models are directly applied to dataset2 to evaluate and compare their generalization performance. The distribution of SOCD and SOCS in soils of various types and textures is analyzed using the optimal interpolation method. The results indicated that: (1) The average SOC densities predicted by OK interpolation, RF, and SVM are 3.70, 3.74, and 3.63 kg/m, with test set precisions (R) of 0.34, 0.60, and 0.81, respectively. (2) ML achieves a significantly higher predictive precision than traditional OK interpolation. The RF model's precision is 0.21 higher than the SVM model and more precise in estimating carbon stock. (3) When applied to the dataset2, the RF model exhibited superior generalization capabilities (R = 0.52, MSE = 0.32) over the SVM model (R = 0.32, MSE = 0.45). (4) The spatial distribution of surface SOCD in the study area exhibits a decreasing gradient from west to east and from south to north. The total carbon stock in the study area is estimated at approximately 10.76 × 10t. (5) The integration of soil attribute variables, climatic variables, remote sensing data, and machine learning techniques holds significant promise for the high-precision and high-quality mapping of soil organic carbon density (SOCD) in agricultural soils.
Occurrence of selected Covid-19 drugs in surface water resources: a review of their sources, pathways, receptors, fate, ecotoxicity, and possible interactions with heavy metals in aquatic ecosystems
The outbreak of the coronavirus disease 2019 (Covid-19) led to the high consumption of antibiotics such as azithromycin as well as corticosteroids such as prednisone, prednisolone, and dexamethasone used to treat the disease. Seemingly, the concentrations of these four Covid-19 drugs increased in wastewater effluents and surface water resources. This is due to the failure of traditional wastewater treatment facilities (WWTFs) to eliminate pharmaceuticals from wastewater. Therefore, the objective of the current research was to review the present state of literature on the occurrence of four Covid-19 drugs in water resources, the associated risks and toxicity, their fate, as well as the emergence of combined pollutants of Covid-19 drugs and heavy metals. From late 2019 to date, azithromycin was observed at concentrations of 935 ng/L, prednisone at 433 ng/L, prednisolone at 0.66 ng/L, and dexamethasone at 360 ng/L, respectively, in surface water resources. These concentrations had increased substantially in water resources and were all attributed to pollution by wastewater effluents and the rise in Covid-?19 infections. This phenomenon was also exacerbated by the observation of the pseudo-persistence of Covid-19 drugs, long half-life periods, as well as the excretion of Covid-19 drugs from the human body with about 30?90% of the parent drug. Nonetheless, the aquatic and human health toxicity and risks of Covid-19 drugs in water resources are unknown as the concentrations are deemed too low; thus, neglecting the possible long-term effects. Also, the accumulation of Covid-19 drugs in water resources presents the possible development of combined pollutants of Covid-19 drugs and heavy metals that are yet to be investigated. The risks and toxicity of the combined pollutants, including the fate of the Covid-19 drugs in water resources remains a research gap that undoubtably needs to be investigated.
The impact of prenatal exposure to fine particulate matter and its components on maternal and neonatal thyroid function and birth weight: a prospective cohort study
Maternal and child health has garnered considerable attention recently. The effects of prenatal exposure to PM and its components on thyroid function in both mothers and fetuses, as well as on offspring birth weight, remain unexplored. This study involved 446 mother-infant pairs from a cohort study in Ma'anshan, China, during 2021-2022. Air pollution data were obtained from the Tracking Air Pollution (TAP) project. Thyroid hormone levels (FT, FT, and TSH) were measured in maternal blood samples taken at various pregnancy stages and in cord blood. We employed multiple analytical methods to evaluate the effects of PM and its components on maternal thyroid function and birth weight z-score (BWz). The GLR analysis reveals that the effect of PM and its components on BWz differs according to the pregnancy stage and the specific pollutant involved. During the late pregnancy, increased exposure to PM and specific components (for instance, and ) was correlated with elevated maternal FT levels (p < 0.05) and reduced BWz (p < 0.05). QgC results illustrated a notable negative correlation between heightened PM exposure and BWz in late pregnancy. BKMR analysis confirmed that overall exposure to PM and its components negatively impacted BWz during the third trimester. Mediation analysis showed that changes in maternal FT levels accounted for approximately 8.52%, 8.05%, and 8.13% of the negative effects on BWz from exposure to , and , respectively (p < 0.05). In healthy pregnancies, exposure to PM and its components during the late pregnancy is linked to alterations in maternal thyroid hormone levels, potentially leading to reduced birth weight. Maternal FT levels may mediate the connection between PM components exposure and reduced the weight of offspring.
Distribution, assessment, and causality analysis of soil heavy metals pollution in complex contaminated sites: a case study of a chemical plant
To effectively prevent and control pollution from heavy metals (HMs) in urban soils, it is essential to thoroughly understand the contamination status of contaminated sites. In this study, the contamination status and sources of six HMs (As, Cu, Cr, Ni, Pb, Cd) in the soil of a decommissioned chemical plant in southern China were comprehensively analyzed. The results indicated that the average concentration of HMs followed the sequence: Cr > Pb > Cu > Ni > As > Cd. Heavy metal accumulation in the upper soil layer was predominantly observed in industrial zones and low-lying areas, with notable variations in concentration along the vertical profile. Certain sections of the site exhibited severe HM contamination, particularly with Cu levels exceeding the background value by 46.77 times. Cd presented significant ecological risks in specific areas, with an average Ecological Index of 96.09. Carcinogenic and non-carcinogenic risks were identified at three and six sampling points, respectively, with sampling point S103 demonstrating both types of risks. The causes of HM contamination were primarily attributed to anthropogenic activities. Horizontal dispersion was mainly influenced by production operations and topographical features, while vertical distribution was predominantly affected by the permeability characteristics of the strata. The causality analysis incorporating production activities and topographical factors provides novel perspectives for understanding sources of contamination at contaminated sites. The study outcomes can offer guidance for the assessment and surveying of urban industrial pollution sites.
Chemical analysis of toxic elements: total cadmium, lead, mercury, arsenic and inorganic arsenic in local and imported rice consumed in the Kingdom of Saudi Arabia
Rice consumption is a pathway for human exposure to toxic elements. Although rice is a major staple in the Kingdom of Saudi Arabia (KSA) there is limited published data about its toxic element composition. Both imported and locally grown Hassawi rice in Saudi Arabia were collected, digested then analysed by HPLC-ICP-MS for inorganic arsenic (i-As) and by ICP-MS for As, Cd, Pb and Hg. Of these toxic elements, i-As was present at concentrations that might give rise to material concerns about human exposure and public health. Hassawi rice (mean 43 ± 5 µg/kg) was found to have significantly lower concentrations of i-As than imported rice (mean 73 ± 8 µg/kg). The estimated exposure of adults consuming imported rice in one KSA city reached 0.3 µg/kg-bw/day, within the margin of safety of the recently withdrawn WHO PTWI for i-As of 2.1 µg/kg-bw/day and higher than EFSA's 0.06 µg/kg-bw/day skin cancer BMDL.
Hydrochemical characteristics, cross-layer pollution and environmental health risk of groundwater system in coal mine area: a case study of Jiangzhuang coal mine
Long-term coal mining activities have significantly disturbed the groundwater system, resulting in aquifer water characterized by high levels of Na, SO, and total dissolved solid (TDS), posing environmental health risks. To investigate the disturbance effects of coal mining activities on the groundwater system and ascertain the goaf water (OGW) environmental impacts, this study focuses on the surface water (SW), major aquifers, and OGW of Jiaozhuang Coal Mine. Through ion analysis and self-organizing map (SOM) clustering, the study analyzes the hydrochemical characteristics of the aquifer water, summarizes the accumulation patterns of OGW, and evaluates water quality of irrigation and drinking using sodium adsorption ratio (SAR), sodium percentage (SSP), and comprehensive pollution index (F). The results show that the hydrochemical characteristics of the groundwater system are influenced by a combination of cation exchange, dissolution, and mixing processes, with deep aquifers exhibiting high Na and SO levels. The OGW mainly originates from the coal roof sandstone aquifers water (RSW) and 3rd limestone aquifer water (3LW). Additionally, the groundwater shows high alkalinity and salinity hazards, with irrigation water quality assessments falling into general and unsuitable water quality area. Moreover, the groundwater quality is below Class III standards, with the worst being Class V, rendering it unsuitable as a drinking water source. Untreated discharge of OGW to the surface can easily threaten human drinking water health. The study results are helpful in identifying and controlling groundwater pollution caused by coal mining, ensuring the safety and sustainable utilization of water resources in mining areas and surrounding regions.
Distribution of heavy metals in the sediments of Ganga River basin: source identification and risk assessment
Sediment serves as a heavy metal store in the riverine system and provides information about the river's health. To understand the distribution of heavy metal content in the Ganga River basin (GRB), a total of 25-bed sediment and suspended particulate matter (SPM) samples were collected from 25 locations in December 2019. Bed sediment samples were analyzed for different physio-chemical parameters, along with heavy metals. Due to insufficient quantity of SPM, the samples were not analyzed for any physio-chemical parameter. The metal concentrations in bed sediments were found to be as follows: Co (6-20 mg/kg), Cr (34-108 mg/kg), Ni (6-46 mg/kg), Cu (14-210 mg/kg), and Zn (30-264 mg/kg) and in SPM, the concentrations were Co (BDL-50 mg/kg), Cr (10-168 mg/kg), Ni (BDL-88 mg/kg), Cu (26-80 mg/kg), and Zn (44-1186 mg/kg). In bed sediment, a strong correlation of 0.86 and 0.93 was found between Ni and Cr, and Cu and Zn respectively and no significant correlation exists between organic carbon and metals except Co. In SPM, a low to moderate correlation was found between all the metals except Zn. The risk indices show adverse effects at Pragayraj, Fulhar, and Banshberia. Two major clusters were formed in Hierarchal Cluster Analysis (HCA) among the sample points in SPM and bed sediment. This study concludes that the Ganga River at Prayagraj, Banshberia, and Fulhar River is predominately polluted with Cu and Zn, possibly posing an ecological risk. These results can help policymakers in implementing measures to control metal pollution in the Ganga River and its tributaries.
Cultivable bacteria contribute to the removal of diclofenac and naproxen mix in a constructed wetland with Typha latifolia
Constructed wetlands are used to remove diclofenac and naproxen from wastewater. However, the role of plants and their root-associated bacteria in removing these pharmaceuticals is still unknown. In this work, bacteria were isolated from the roots of Typha latifolia cultivated in a constructed wetland to treat a diclofenac and naproxen mix. 16S rDNA sequencing indicated that bacterial isolates belong to the Pseudomonas, Serratia, and Rahnella genera. All bacterial isolates showed tolerance to high concentrations of diclofenac and naproxen and had differential laccase activity, phosphate-solubilizing activity, and indole acetic acid production.Bacteria were grouped into three consortia A (0-30 cm), B (50-80 cm), and C (100-130 cm), according to the site from which they were isolated in the wetland. Plant-bacteria interaction assays were conducted to determine the removal capacity of diclofenac and naproxen mix by the bacterial consortia or their interaction with T. latifolia. The results showed that all bacterial consortia removed over 50% of diclofenac and naproxen, while in their interaction with T. latifolia the removal capacity increased to over 70%. Consortium B was the most efficient in removing diclofenac and naproxen, with removal rates of 63.85 ± 0.45% and 74.93 ± 0.75%, respectively. Meanwhile, in the interaction of consortium B with T. latifolia, the removal of diclofenac and naproxen increased to 82.27 ± 0.30% and 88.12 ± 1.23%, respectively. Overall, the results indicated that T. latifolia and its root-associated bacteria removed the diclofenac and naproxen mix in the constructed wetland, contributing to understanding the role of the plant and bacteria in removing emerging contaminants. Therefore, the interaction of T. latifolia and its root-associated bacteria could potentially be used in strategies to remove emerging contaminants from wastewater.
Chromium supplementation and type 2 diabetes mellitus: an extensive systematic review
Diabetes is a global public health concern with increasing prevalence worldwide. Chromium (Cr), a trace element found in soil, water, and food, has been proposed to have a possible positive effect in glucose metabolism and diabetes mellitus prevention. However, the relationship between trivalent chromium [Cr(III)] exposure, mainly through the consumption of diet supplements, and type 2 diabetes mellitus (T2DM) remains controversial. An extensive systematic review of the current literature on randomized controlled studies (RCTs) was conducted from 1 January 2000, to January 2024 using the databases PubMed, Scopus, ScienceDirect, and Cochrane, with specific keywords and inclusion as well as exclusion criteria. After close screening of the research studies retrieved from the mentioned websites was conducted, the most related studies were included in the final systematic review. The studies were evaluated for the degree of relevance, quality, and risk bias, using appropriate quality assessment tools. Several of the included RCT studies reported possible benefits of Cr(III) supplementation, mainly in the form of chromium picolinate (CrPic), chromium yeast (CY), chromium chloride (CrCl), and chromium nicotinate (CrN). The dosage of chromium was between 50 and 1000 μg/day and it was consumed from 2 to 6 months. Glycemic control markers, including FPG, insulin, HbA1C, and HOMA-IR levels, significantly decrease following chromium supplementation, mainly in studies with a longer intervention period. Supplementing with chromium (Cr) indicated that could significantly improve lipid profile by raising high-density lipoprotein and lowering triglyceride and total cholesterol while having little effect on low-density lipoprotein. However, most research findings include significant limitations, such as inconsistent dosage and type of chromium, formulation of supplements, and study duration. Further well-designed and high-quality research is needed to fully understand the role of chromium dietary supplementation and the potential risks related to its mechanisms of action, type, and dose, in the prevention and treatment of type 2 diabetes mellitus.
Association between exposure to arsenic, cadmium, and lead and chronic kidney disease: evidence from four practical statistical models
Environmental exposure to arsenic (As), lead (Pb) and cadmium (Cd) may cause chronic kidney disease (CKD), with varying independent effects and unclear combined impact. This study aimed to evaluate these effects on CKD.