In recent years, there is a growing interest towards the green synthesis of metal nanoparticles, particularly from plants; however, yet no published study on the synthesis of ZnO.NPs using the ...Deverra tortuosa extract. Through this study, zinc oxide nanoparticles (ZnO.NPs) have been synthesized based on using the environmentally benign extract of the aerial parts of D. tortuosa as a reducing and capping agent. ZnO.NPs synthesis was confirmed using UV-Visible (UV-Vis) spectroscopy, Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD) and High Resolution-Transmission Electron Microscope (HR-TEM). The qualitative and quantitative analyses of plant extract were done. The potential anticancer activity was in vitro investigated against two cancer cell lines (human colon adenocarcinoma "Caco-2" and human lung adenocarcinoma "A549") compared to their activities on the human lung fibroblast cell line (WI38) using the MTT assay. Both the aqueous extract and ZnO.NPs showed a remarkable selective cytotoxicity against the two examined cancer cell lines.
In order to identify spatial relationship of heavy metals in soil–rice system at a regional scale, 96 pairs of rice and soil samples were collected from Wenling in Zhejiang province, China, which is ...one of the well-known electronic and electric waste recycling centers. The results indicated some studied areas had potential contaminations by heavy metals, especially by Cd. The spatial distribution of Cd, Cu, Pb and Zn illustrated that the highest concentrations were located in the northwest areas and the accumulation of these metals may be due to the industrialization, agricultural chemicals and other human activities. In contrast, the concentration of Ni decreased from east to west and the mean concentration was below the background value, indicating the distribution of Ni may be naturally controlled. Enrichment index (EI) was used to describe the availability of soil heavy metals to rice. The spatial distribution of EIs for Cd, Ni and Zn exhibited a west-east structure, which was similar with the spatial structures of pH, OM, sand and clay. Cross-correlograms further quantitatively illustrated the EIs were significantly correlated with most soil properties, among which; soil pH and OM had the strongest correlations with EIs. However, EI of Cu showed relative weak correlations with soil properties, especially soil pH and OM had no correlations with EI of Cu, indicating the availability of Cu may be influenced by other factors.
► Iron and Hg strongly polluted sea water. ► Mn and Al moderately polluted but Cd and Pb slightly polluted the sea water. ► Iron, Pb, and Hg strongly polluted groundwater. ► Mn and Al moderately ...polluted but As slightly contaminated the groundwater. ► Fe, Mn, Zn, Ni, Cr, Cu, Cd, Pb, As, Al and Hg of sea water exceeded the average concentrations of elements.
This study reveals potential accumulation of trace metals in the sea and groundwater due to ship breaking activities which take place along the Bay of Bengal in Sitakund Upazilla, Chittagong, Bangladesh. When compared with WHO and Bangladesh domestic standards for water quality, it is revealed that seawater was strongly polluted by Fe and Hg, moderately by Mn and Al, and slightly by Pb and Cd. Groundwater was strongly polluted by Fe, Pb and Hg, moderately by Mn and Al, and slightly by As. Trace element concentrations of all seawater samples exceeded the average concentration of elements in the Earth’s seawater. The application of Principal Components Analysis identified two sources of pollution–marine and ship breaking. The mechanism of groundwater pollution inferred that if seawater is polluted, nearby groundwater is also polluted with trace metals due to the influence of seawater intrusion.
The Tista is a Trans-Himalayan river that flows through Sikkim and West Bengal states of India and Rangpur division of Bangladesh and finally falls into the Brahmaputra River. The presence of ...numerous abandoned channels with various degrees of aggradations indicates large migrations of the Tista River. The pH value of groundwater varies from 6.20 to 7.40 which indicate the slightly alkaline to acidic nature of the studied aquifers. The mean abundance of major cations is Na
+
> Ca
+2
> Mg
+2
> K
+
, whereas the major anions is HCO
3
−
> Cl
−
> SO
4
−2
. Among the cations, Na
+
is the dominant and K
+
is the lowest constituents, whereas HCO
3
−
is most abundant and SO
4
−2
is the minor constituents in anions. The hydrochemical facies of groundwater show that sodium, sodium–magnesium, sodium–calcium, sodium–magnesium–calcium and sodium–calcium–magnesium are cation facies and chloride–bicarbonate, bicarbonate–chloride and bicarbonate are anion facies. Correlating with WHO (Guidelines for drinking-water quality, 1, World Health Organisation, Geneva,
1997
) and EQS (Environmental quality standard, Department of Environment, Bangladesh, 1989) guideline values for drinking water and public health, it may be concluded that the groundwater of the study area is suitable for all drinking and domestic purposes, where only three samples exceed the maximum allowable limit of potassium. Based on total hardness, SAR, RSC, PI, SSP and MH values, it can be summarized that the groundwater of the investigated area is suitable for irrigation purpose. On the basis of Australian and UNESCO standard, the groundwater of the study area is also suitable for livestock purposes. The Rangpur area is hydrogeologically active by the processes like ion exchange and dissolution. Ca
2+
, Mg
2+
and HCO
3
−
are produced by the dissolution of limestone and dolomite.
The extraordinary accumulation of cyanide ions within biological cells is a severe health risk. Detecting and tracking toxic cyanide ions within these cells by simple and ultrasensitive methodologies ...are of immense curiosity. Here, continuous tracking of ultimate levels of CN−-ions in HeLa cells was reported employing biocompatible branching molecular architectures (BMAs). These BMAs were engineered by decorating colorant-laden dendritic branch within and around the molecular building hollows of the geode-shelled nanorods of organic–inorganic Al-frameworks. Batch-contact methods were utilized to assess the potential of hollow-nest architecture for inhibition/evaluation of toxicant CN--ions within HeLa cells. The nanorod BMAs revealed significant potential capabilities in monitoring and tracking of CN− ions (88 parts per trillion) in biological trials within seconds. These results demonstrated sufficient evidence for the compatibility of BMAs during HeLa cell exposure. Under specific conditions, the BMAs were utilized for in-vitro fluorescence tracking/sensing of CN− in HeLa cells. The cliff swallow nest with massive mouths may have the potential to reduce the health hazards associated with toxicant exposure in biological cells.
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•Visual detection and tracking toxic cyanide ions in biological HeLa cells.•Design of branching molecular architectures (BMAs) for monitoring of CN- ions.•Organic–inorganic Al frameworks nanorods provided building blocks for BMAs.•Potential tracking of CN−ions (88 parts per trillion) in biological trials within seconds.•In-vitro fluorescence tracking/sensing of CN− in HeLa cells.
Adsorption−desorption of arsenic is the primary factor that impacts the bioavailability and mobility of arsenic in soils. To examine the characteristics of arsenate As(V) adsorption−desorption, ...kinetic batch experiments were carried out on three soils having different properties, followed by arsenic release using successive dilutions. Adsorption of As(V) was highly nonlinear, with a Freundlich reaction order N much less than 1 for Olivier loam, Sharkey clay, and Windsor sand. Adsorption of arsenate by all soils was strongly kinetic, where the rate of As(V) retention was rapid initially and was followed by gradual or somewhat slow retention behavior with increasing reaction time. Freundlich distribution coefficients and Langmuir adsorption maxima exhibited continued increase with reaction time for all soils. Desorption of As(V) was hysteretic in nature and is an indication of lack of equilibrium retention and/or irreversible or slowly reversible processes. A sequential extraction procedure provided evidence that a significant amount of As(V) was irreversibly adsorbed on all soils. A multireaction model (MRM) with nonlinear equilibrium and kinetic sorption successfully described the adsorption kinetics of As(V) for Olivier loam and Windsor sand. The model was also capable of predicting As(V) desorption kinetics for both soils. However, for Sharkey clay, which exhibited strongest affinity for arsenic, an additional irreversible reaction phase was required to predict As(V) desorption or release with time.
This study reveals that some trace metals were found in sediments of the Sitakund Upazilla of Chittagong, Bangladesh, largely due to ship breaking activities in the area. This was seen when comparing ...levels of trace metals in the sediments of the study area with the recommended values of unpolluted sediments. Thus, it was inferred that the trace metal concentrations around the ship breaking area were higher than that of the control site, Sandwip, and near the Karnafully River mouth. The trace elements in the sediment samples were significantly correlated with one another. Enrichment factor values of the sediment samples revealed that most of the sediments were minor to severely enriched by trace metals. Sediments of three stations out of 11 stations of the study area were minor to moderately enriched by Cd metal. The geo-accumulation index (Igeo) values of the sediment samples revealed that the sediments of the ship breaking area were affected from slight to strong contamination with trace metals and sediments in two stations of the study area were affected moderately contaminated by Cd metal. Potential contamination indices of the sediment samples indicated that Cr, Zn, As, and Pb were the greatest contaminants.
► The trace metal around ship breaking area was higher than that of control site. ► The geo-accumulation index values of the sediments were moderately enriched by Cd. ► Potential contamination indices of the sediments were affected moderately from Cd. ► This high level of Cd might be due to the runoff from dismantling of old ships.
Parkinson's disease (PD) is a progressive neurodegenerative disorder affecting the substantia nigra where functions controlling body movement take place. Manganese (Mn) overexposure is linked to a ...neurologic syndrome resembling PD. Sesamol, thymol, wheat grass (WG), and coenzyme Q10 (CoQ10) are potent antioxidants, anti-inflammatory, and anti-apoptotic nutraceuticals. We investigated the potential protective effects of these nutraceuticals alone or in combinations against MnCl
-induced PD in rats. Seven groups of adult male Sprague Dawley rats were categorized as follows: group (I) was the control, while groups 2-7 received MnCl
either alone (Group II) or in conjunction with oral doses of sesamol (Group III), thymol (Group IV),
(Group V),
(Group VI), or their combination (Group VII). All rats were subjected to four behavioral tests (open-field, swimming, Y-maze, and catalepsy tests). Biochemical changes in brain levels of monoamines,
,
,
,
/glutamate, as well as oxidative stress, and apoptotic and neuroinflammatory biomarkers were evaluated, together with histopathological examinations of different brain regions. Mn increased catalepsy scores, while decreasing neuromuscular co-ordination, and locomotor and exploratory activity. It also impaired vigilance, spatial memory, and decision making. Most behavioral impairments induced by
were improved by sesamol, thymol,
, or
, with prominent effect by sesamol and thymol. Notably, the combination group showed more pronounced improvements, which were confirmed by biochemical, molecular, as well as histopathological findings. Sesamol or thymol showed better protection against neuronal degeneration and some behavioral impairments induced by Mn than WG or CoQ10, partly via interplay between
and
pathways.
Elemental composition, multivariate statistical analyses with the absolute principal component score-multiple linear regression (APCS–MLR) model, and different pollution indices in Upper and Lower ...Southwestern Ganges–Brahmaputra–Meghna (GBM) delta sediments were studied to characterize pollution, ecological risk and quantify potential toxic element sources of the area. Toxic metals concentrations were higher in Lower Delta and individual pollution indices showed Upper Delta was moderately polluted by arsenic, chromium, cobalt, copper and lead, and Lower Delta was moderately–strongly polluted by the same metals. Synergistic indices include Potential Ecological, Toxic, Nemerow, and Pollution Risk indices in Upper and Lower Delta sediment ranged from 47.17–128.07, 2.03–12.19, 29.92–65.42, 0.28–1.62, and 69.17–246.90, 8.00–13.47, 20.53–152.92, 1.18–1.58, indicated low and moderate risk pollution, respectively. Statistical models represent the metals dominantly originated from nature for Upper Delta, and both natural and anthropogenic activities contributed to Lower Delta sediment. The study found that the modern deposit in Lower Delta became more contaminated and thus enhanced ecological risk.
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•Toxic heavy metals concentrations were higher in modern sediments in the Lower Delta compared to the Upper.•Upper Delta sediment exhibited low-risk pollution, but moderate pollution showed in the Lower Delta Plain.•Toxic metals in Upper Delta originated from nature, and both natural and anthropogenic activities contribute to Lower Delta Plain.•Effluents containing toxic elements discharged to rivers contaminated the Lower Delta sediments more, compared to the Upper.
Groundwater and core sediments of two boreholes (to a depth of 50
m) from the Chapai-Nawabganj area in northwestern Bangladesh were collected for arsenic concentration and geochemical analysis. ...Groundwater arsenic concentrations in the uppermost aquifer (10–40
m of depth) range from 2.8
μg
L
−1 to 462.3
μg
L
−1. Groundwater geochemical conditions change from oxidized to successively more reduced, higher As concentration with depth. Higher sediment arsenic levels (55
mg
kg
−1) were found within the upper 40
m of the drilled core samples. X-ray absorption near-edge structure spectroscopy was employed to elucidate the arsenic speciation of sediments collected from two boreholes. Environmental scanning electron microscopy and transmission X-ray microscopy were used to investigate the characteristics of FeOOH in sediments which adsorb arsenic. In addition, a pH–Eh diagram was drawn using the Geochemist's Workbench (GWB) software to elucidate the arsenic speciation in groundwater. The dominant groundwater type is Ca–HCO
3 with high concentrations of As, Fe and Mn but low levels of NO
3
− and SO
4
2−. Sequential extraction analysis reveals that Mn and Fe hydroxides and organic matter are the major leachable solids carrying As. High levels of arsenic concentration in aquifers are associated with fine-grained sediments. Fluorescent intensities of humic substances indicate that both groundwater and sediments in this arsenic hotspot area contain less organic matter compared to other parts of Bengal basin. Statistical analysis clearly shows that As is closely associated with Fe and Mn in sediments while As is better correlated with Mn in groundwater. These correlations along with results of sequential leaching experiments suggest that reductive dissolution of MnOOH and FeOOH mediated by anaerobic bacteria represents an important mechanism for releasing arsenic into the groundwater.
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