Search

Underground water were abstracted from HDWs to determine their suitability for drinking. Physical, chemical and bacteriological parameters were carried out following standard guidelines. Total coliform count was done using the membrane filtration method. Heavy metal was determined using an Atomic Absorption Spectrophotometer (AAS BULK SCIENTIFIC MODEL 210 VGP). Samples were subjected to statistical and multivariate analysis. Results of physicochemical parameters show that they were all within the WHO standard for drinking. Cation concentrations follow the order: Na+ > Ca2+ > Mg2+ > K+, while anions are: HCO3− > SO42-> Cl−> NO3− > PO42-. As, Cd and Pb were not detected in the sampled water, but other heavy metals Cr, Cu, Fe, Mn and Zn were detected. They were, however, within the WHO's recommended range. Based on E. coli analysed, all of the water samples were free from faecal contamination since none was discovered in the water samples. Based on the water quality index, only sample G hand-dug well is of poor quality (though it could be treated) for human consumption; all other samples are good for human consumption. Deductions from Pipers' and the Durov diagram, as well as principal component analysis, revealed that there was little geological and human activity within the hand-dug wells. Based on the physicochemical, microbiological, heavy metal and water quality indexes, this study indicates that all of the water samples examined are free of pollution, but that continual monitoring of the hand-dug wells should be prioritised. [ABSTRACT FROM AUTHOR]

Concentrations of 222Rn and other toxic metals (Ni, Cu, Fe, Cd, Zn, Pb, Cr, and Mn) were measured by alpha spectrometry using Rad7 and atomic absorption spectrophotometry, respectively, in the water samples from the Ilokun dumpsite, Ado-Ekiti, Nigeria. The physicochemical parameters of the groundwater were also assayed to determine its suitability for drinking and irrigation purposes. While the physicochemical parameters met the World Health Organization (WHO)-safety standards, Cu, Fe, Cd, Pb, Cr, and Mn exceeded permissible limits. Hazard index (HI) values for adults (8.40) and children (39.23) indicated heightened susceptibility to non-carcinogenic health risks among both age group populations. The 222Rn concentrations present in the studied samples range from 5.4 to 23.1 Bq l−1 with an average of 13.9 Bq l−1. Approximately 60% of the samples have radon concentrations above the US Environmental Protection Agency (EPA)-maximum contaminant level of 11.1 Bq l−1. The evaluated radiation doses to the stomach and respiratory tract due to radon content in the water are well below the WHO-specified individual dose criterion of 0.1 mSv year−1. This study suggests a need for groundwater resource management strategies and measures to protect human health from radiological and toxicological risks associated with groundwater consumption around the Ilokun dumpsite. [ABSTRACT FROM AUTHOR]

A main constraint of hydroponics is the need for high-quality water. This study evaluated the viability of reverse osmosis concentrate backflush, or reject water, as a water source for hydroponic lettuce production. We compared the growth of ‘Casey’ butterhead lettuce produced using nutrient film technique hydroponics with municipal (tap) water (TW), reverse osmosis (RO) water, and reject water from an RO system [wastewater (WW)]. Characterization of water sources showed the following: RO had trace minerals; TW had the greatest potassium (K), calcium (Ca), and magnesium (Mg); and WW had greatest sulfur (S), sodium (Na), and chloride (Cl). No water source had detectable heavy metals. Mineral and heavy metal tissue contents were determined at mid-harvest and end-harvest, and nutrient budgets for nitrogen (N), S, Ca, Mg, Na, and Cl were calculated. Water sources did not impact lettuce growth during the 4-week hydroponic production cycle based on leaf greenness, diameter, fresh weight, or dry weight. In the nutrient reservoirs, Ca and Mg increased over time and were greatest in TW. The Cl and Na levels in WW were 106 and 203 mg·L-1, respectively, and the electrical conductivity (EC) of this treatment increased to 3.5 dS·m-1 after 4 weeks; however, plant water uptake, water use efficiency, and percent moisture loss were unaffected. In shoot tissue, lettuce grown with WW had less Ca at mid-harvest and less Mg at mid-harvest and end-harvest compared with other treatments, suggesting antagonization of uptake by high salt. Tissue S was not different across treatments; however, there were differences in reservoirs of the water sources as S accumulated more from WW. Tissue Na and Cl levels were different among the treatments, and higher amounts in nutrient reservoirs translated to higher uptake by lettuce. Although the heavy metal content in all water sources was <0.01 ppm, arsenic, lead, and chromium were measured in lettuce tissue at levels that exceed recommended limits in most instances. Our results indicated that a water source of RO reject water from municipal feed water is a viable irrigation option for shortterm hydroponic production of butterhead lettuce; however, EC reduction in the nutrient solution would be necessary when continuing sequential cropping [ABSTRACT FROM AUTHOR]

There are many reservoirs, ponds and Korotoa River in the capital of ancient Pundranagar, Bangladesh, which is an intensive agricultural region. Since different industries are operated for the preparation of different agricultural instruments and agrochemicals are extensively applied to the agricultural soils which mix with the river and pond water and these water bodies may be contaminated with trace elements. In this study, levels of nine trace elements (Cr, As, Cu, Ni, Zn, Cd, Fe, Mn and Pb) and physicochemical properties in surface water from one river and five ponds were measured and compared with water quality guidelines. In addition, health risks, pollution status and possible sources of trace elements were assessed. The mean concentrations of As, Cd, Pb, Cr, Ni, Cu, Fe, Mn and Zn in pond water were 0.059, 0.033, 0.067, 0.136, 0.133, 0.280, 0.733, 0.127 and 0.266 mg/L and river water were 0.055, 0.037, 0.054, 0.104, 0.120, 0.230, 0.702, 0.125 and 0.200 mg/L, respectively. Except Cu and Zn, the mean concentrations of trace elements were above the water quality permissible standards indicating water from these sources is not safe for human use. The WQI values suggested that the water quality is excellent to poor water quality class. Health risk indices indicated that As in water via ingestion exposure pathway may pose both non-carcinogenic and carcinogenic health risks to the residents where the non-carcinogenic risk to the residents is raised from ingestion of As, Cd, Cr and Pb from water. [ABSTRACT FROM AUTHOR]

The concentrations of cadmium, copper, lead, zinc, nickel, and chromium in samples of sediment, water, and Typha angustifolia plants in the stream of the Drenica River were determined to assess the level of pollution. According to sediment analysis results from seven locations, the concentrations of Cu, Ni, Zn, and Cr exceeded the permitted limits according to WHO standards from 1996. In the plant samples, the concentrations of Cd and Pb were above the allowed limits according to GD161 and ECE standards, and according the WHO standard, the water quality in the Drenica River is classified into the first, second, and third quality categories. The results of this study show the bioaccumulation coefficient in Typha angustifolia plants, and it was found that the most bioaccumulated of the metals is Cd, with a bioaccumulation coefficient (BAF) greater than 1. The pollution load index (PLI), enrichment factor (EF index), Geoaccumulation index (Igeo), potential ecological risk factor (Eif), and potential ecological risk index (RI) were used in combination to assess the degree of pollution and the environmental risk presented to the freshwater ecosystem of the Drenica River. The results show that the Drenica River is mainly polluted by Ni, Cu, and Cr, reflecting substantial impacts of anthropogenic activities, including sizeable industrial effects, the development of urbanism, agricultural activities, and the deposition of waste from a ferronickel factory in the area. [ABSTRACT FROM AUTHOR]

Due to the presence of heavy metals in wastewater treatment and manufacturing water purification processes in industries, investigations into potential methods have been widely conducted. In this paper, we report the incorporation of cation-exchange for removing heavy metals from aqueous solutions. We further investigated the properties cation-exchange using potential step method on PPy/PVS film at titanium electrode. Satisfactory results have been obtained with the small scale of experimental. It was found that the PPy/PVS film is able to remove heavy metal ions such as copper, nickel, and cobalt at very low concentrations, less than or equal to 10 mg/L, reducing them to approximately 1 mg/L. The Leica Q500MC Image Processing and Analysis system displayed the uneven deposition of heavy metal ions on the surface of PPy/PVS. Furthermore, Electron Spectroscopy for Chemical Analysis (ESCA) demonstrated the deposition of heavy metals on the PPy/PVS film. [ABSTRACT FROM AUTHOR]

Rice intake represents a significant pathway through which humans accumulate heavy metals. This study presents a comprehensive analysis of heavy metal and pesticide contamination in rice cultivars irrigated with industrial wastewater near Dhaka, Bangladesh, a region heavily influenced by industrial activities. This study employed a unique methodology that not only quantified the concentrations of heavy metals and pesticide residues in rice grains but also extended to evaluating the physicochemical properties of rice stems, husks, soil, and irrigation water. The findings revealed alarmingly high levels of heavy metals such as lead, cadmium, chromium, nickel, and mercury in the soil and irrigation water, with concentrations in some cases exceeding the World Health Organization safety thresholds by 2 to 15 times. Notably, the rice grains also exhibited significant contamination, including substantial amounts of diazinon and fenitrothion pesticides, exceeding the established safety limits. The study employed hazard quotients (HQs) and cancer risk (CR) assessments to evaluate the potential health risks associated with the consumption of contaminated rice. The results indicated HQ values were greater than 1 for rice grains across the sampled fields, suggesting a considerable non-carcinogenic health risk, particularly from lead exposure, which was found at levels twice the standard limit in all the sampling fields. Moreover, the CR values for As, Pb, Cd, Co, and Mn highlighted a significant carcinogenic risk in several instances. [ABSTRACT FROM AUTHOR]

This study investigates the heavy metal concentrations in water and sediment samples from three stations in coastal marine wetlands in Rivers State, Nigeria: Sangama, Degema, and Tema. Samples were collected monthly from October 2021 to April 2022. Igeo, metal pollution load index (MPLI), ecological risk assessment, ecological risk factor (Er), and potential ecological risk index (PERI) were used to evaluate the impact of pollution levels. The average concentrations of heavy metals like Fe, Zn, Pb, Cd, and Cu were analyzed to assess contamination levels and ecological risks. Results show spatial variations in metal concentrations, with Sangama having the highest levels in both water and sediment. The geoaccumulation index (Igeo) and ecological risk factor (Er) were used to evaluate contamination levels and risks. Tema and Degema have generally favourable conditions with low to moderate contamination, while Sangama shows higher levels, especially for Cd, Pb, and Cu. The potential ecological risk index (PERI) and metal pollution load index (MPLI) emphasize the significant ecological risks from heavy metal pollution at all three stations. Urgent action is needed to implement effective environmental management strategies and reduce the impacts of metal pollution on aquatic ecosystems in these areas. [ABSTRACT FROM AUTHOR]

Heavy metal Cr(VI) and organic BPA have posed harmful risks to human health, aquatic organisms and the ecosystem. In this work, Chitosan/bone/bamboo biochar beads (CS-AMCM) were synthesized by co-pyrolysis and in situ precipitation method. These microbeads featured a particle size of approximately 1 ± 0.2 mm and were rich in oxygen/nitrogen functional groups. CS-AMCM was characterized using XRD, Zeta potential, FTIR, etc. Experiments showed that adsorption processes of CS-AMCM on Cr(VI) and BPA fitted well to Langmuir model, with theoretical maximum capacities of 343.61 mg/g and 140.30 mg/g, respectively. Pore filling, electrostatic attraction, redox, complexation and ion exchange were the main mechanisms for Cr(VI), whereas for BPA, the intermolecular force (hydrogen bond) and pore filling were involved. CS-AMCM with adsorbed Cr(VI) demonstrated effective activation in producing ·OH and ·O2 from H2O2, which degraded BPA and Cr(VI) with the removal rates of 99.2% and 98.2%, respectively. CS-AMCM offers the advantages of low-cost, large adsorption capacity, high catalytic degradation efficiency, and favorable recycling in treating Cr(VI) and BPA mixed wastewater, which shows great potential in treating heavy metal and organic matter mixed pollution wastewater. [ABSTRACT FROM AUTHOR]

The traditional craft villages in Vietnam in general and in Bac Ninh province in particular have been exposing many negative impacts on the environment. The heavy metal-rich wastes from the metal recycling casting craft villages in the field of metal recycling and metal casting are causing severe heavy metal pollution not only to the air, soils, and sediments but also to the groundwater resources. In Da Hoi iron recycling craft village in Chau Khe ward, Tu Son town, Bac Ninh province, Vietnam, the Holocene aquifer is exposed to the Ngu Huyen Khe River's sediments contaminated with heavy metals Lead, Cadmium, Nickel, and Zinc. Freundlich isotherm parameters of the Holocene aquifer have been selected for finite element modeling of heavy metal transport with high temporal and spatial varying retardation factors to get reliable quantitative heavy metals' distribution in depth and time. Initial and boundary conditions have been augmented to be established. The retardation factors of the advection and dispersion transport in the Holocene aquifer for heavy metals Pb, Zn, Cd, and Ni are very highly none-linear and very much varying in time and space: 8.7–66.4 for Pb, 2.0–12 for Zn, 1.7–4.8 for Cd and 1.1–5.9 for Ni. The results of the numerical modeling show that heavy metal transport in the Holocene aquifer is very fast and the entire aquifer thickness has equilibrium aquifer formation and aquifer water heavy concentrations after around 2–2.5 years for Cd and Ni, around 4 years for Zn and around 27 years for Pb. The heavy metals' fluxes from the Holocene aquifer to the Pleistocene aquifer are maximal and more or less constant from the equilibrium time and would cause severe contamination of the Pleistocene aquifer. [ABSTRACT FROM AUTHOR]

A novel electrochemical sensor based on multiwalled carbon nanotubes (MWCNTs) and 1-butyl-3-methylimidazolium hexafluorophosphate (BMIMPF6) hydrophobic ionic liquid for the rapid detection of Pb2+ and Cd2+ was developed. In this study, the BMIMPF6-MWCNTs composite, as well as BMIMPF6 and MWCNTs, were characterized using SEM. The electrochemical studies were performed using Cyclic Voltammetry (CV) and Electrochemical Impedance Spectroscopy (EIS). The BMIMPF6-MWCNTs/GCE exhibited excellent electrochemical activity. The effect of the pH value of 0.1 M NaAc/HAc buffer, deposition potential, and deposition time was investigated. Under the optimal conditions, the linear range for the modified sensors varies from 5 to 1850 µg L−1 for Pb2+ and 22 to 600 µg L−1 for Cd2+. The limit of detection (LOD) for Pb2+ and Cd2+ was 0.9 µg L−1 and 0.5 µg L−1, respectively, and the limit of quantification (LOQ) was 3 µg L−1 for Pb2+ and 1.7 µg L−1 for Cd2+. Moreover, this method showed excellent anti-interference performance, short analysis time, and practicability for determining Pb2+ and Cd2+. The electrochemical sensor was able to determine heavy metal ions in actual water samples without complex pretreatment, with acceptable recoveries from 98 to 110.8% for Pb2+ and 98.6 to 111.3% for Cd2+, demonstrating that the sensor based on BMIMPF6-MWCNTs/GCE can apply for Pb2+ and Cd2+ quantification. [ABSTRACT FROM AUTHOR]

Human welfare and biodiversity are at risk due to the deterioration of water and sediment quality. Particularly, in last few decades, global water and sediment quality degraded due to the rapid industrialization and urbanization. This study aimed to determine the concentration of nine heavy metals and metalloid (Pb, Cr, Cd, Hg, As, Mn, Ni, Cu, and Zn) and assess the ecological risks using different pollution indices (e.g., heavy metal pollution index [HPI], Nemerow pollution index [NI], geo‐accumulation index [Igeo], contamination factor [CF], degree of contamination [CD] and pollution load index [PLI], ecological risk index [ERI]) in water and sediment of the Shitalakshya River, an industrially affected urban river of Bangladesh. For the first time, 20 water and sediment samples were collected across a wider geographical area of the Shitalakshya River during both monsoon and dry seasons and analyzed using the atomic absorption spectrometer. Average concentrations of heavy metals and metalloid in water were within the Bangladesh standard except for Cr (51.69 ppb) and Mn (228.20 ppb) during monsoon season, portraying potential ecological and human health risks. Besides, average concentration of Mn (549.75 and 370.93 ppb), Ni (549.75 and 370.93 ppb), and Cu (45.34 and 36.09 ppb) in sediment during both seasons were above international standard, implying risk to aquatic sediment biota. The average HPI values indicated moderate to high contamination, whereas the NI values implied polluted water in monsoon season with severe pollution in port area of the river. Similarly, Igeo, CF, CD, and PLI elucidated different levels of contamination in the sediment, particularly during dry season. The ERI values also referred moderate ecological risk in the sediment during dry season. Overall, our findings highlight the alarming level of heavy metal pollution in the Shitalakshya River, necessitating immediate action to protect the aquatic environment, sediment biota, and human health. Practitioner points: This study determined the concentration of heavy metals and metalloid in water and sediment of the Shitalakshya River, Bangladesh.The study revealed that the average concentration of Cr and Mn in water exceeded national standard, whereas Mn, Ni, and Cu in sediment exceeded international limit.Potential ecological risk of heavy metals was also assessed using different pollution indices.Calculated pollution indices indicated different degree of pollution, implying critical ecological condition due to heavy metal pollution in aquatic environment and sediment biota. [ABSTRACT FROM AUTHOR]

The present study in the Peenya Industrial Area in Bengaluru, India, carried out to assess the level of heavy metal contamination in the industrial area's soil and groundwater. The study also discusses the potential health risks that inhabitants would suffer from consuming contaminated groundwater. In 116 bore well water samples collected before and throughout the monsoon season, heavy metals including cadmium, chromium, copper, zinc, arsenic, mercury, lead, nickel, and aluminium were examined. Heavy metals concentration (mg/kg) was analysed for 36 soil samples collected in the research area and for heavy metals like chromium, nickel, copper, zinc, arsenic and cadmium. In the current study, the heavy metal pollution index (HPI), hazard index (HQ(ing)) and cancer risk factor (CR) were calculated to assess the potential health risk. The HPI value inside the Peenya industrial area exceeded the critical pollution index value of 100. The hazard index (HQ(ing)) via oral ingestion was found to be > 1.00 in Cr, Hg and As during both seasons, indicating maximum health impacts in the inhabitants of the study area. Cancer index values were > 10-4 in Cr, Ni, Cd, and Pb in the research area, posing cancer risk in people of all ages, from children to adults. Environmental and human health are both put at risk in a polluted region. To assess soil contamination, the following indices were utilized: geoaccumulation (Igeo), single contamination index (PI), and pollution load index (PLI). [ABSTRACT FROM AUTHOR]

Heavy metal pollution seriously threatens the drinking water safety and ecological environment in karst lead–zinc mines. Fifteen groundwater and surface water samples were collected in a karst lead–zinc mine in Daxin, Chongzuo. Ten heavy metal (Mn, Zn, As, Pb, Cr, Cd, Ni, Co, Cu, and Fe) concentrations were detected. Correlation and cluster analysis were utilized to explore the distribution characteristics and sources. The health risks were appraised using the health risk assessment model. The groundwater had more heavy metal types than the surface water, of which the concentrations and average concentrations exceeded the class III water quality standard. The mine drainage contributed most (65.10%) to the heavy metal concentrations. Pb, Zn, Cd, Mn, Co, Ni, Cu, and Fe primarily originated from the mining of the lead–zinc mine, Cr primarily came from the fuel combustion and wear of metals, and As was primarily connected with the regional geological background. The groundwater had a higher total health risk (5.12 × 10−4 a−1) than the surface water (2.17 × 10−4 a−1). In comparison with the non-carcinogenic risk, the carcinogenic risk increased by three to five orders of magnitude. The carcinogenic risk distribution of Cr and Cd represented the health risk pattern. The drinking pathway posed two to three orders of magnitude the amount of health risks that the dermal contact pathway posed. Children suffered greater health risks. Water security for children should be more strictly controlled. Zn, Cd, Pb, Mn, and Cr must be paid more attention in terms of water quality protection and management. [ABSTRACT FROM AUTHOR]

Heavy metal pollution, particularly chromium (VI) contamination, is a significant issue in Indonesian waters due to numerous chromium-producing industries. Research conducted in the downstream waters of Wonorejo found Cr(VI) levels ranging from 0.0025 to 0.018 mg/L, exceeding Indonesia's quality standard of 0.002 mg/L. Thus, it is crucial to treat industrial wastewater containing Cr(VI) before disposal into water bodies. One alternative for treating Cr(VI) waste is using biological agents like microalgae. Chlorella sp. was chosen for this study due to its abundance in Indonesian waters. The study aims to determine the minimum inhibitory concentration (MIC) of Chlorella vulgaris against Cr(VI) and salinity variations. The research involved propagating the microalgae to analyze growth rates and conducting MIC tests against salinity for 14 days with variations of 0, 20, 30, and 40 ppt. MIC tests against Cr(VI) were then performed using the optimal salinity (20 ppt) with variations of 0, 5, 10, 20, 30, and 40 mg/L. Results showed that C. vulgaris can thrive in salinities up to 40 ppt, with the optimal salinity being 20 ppt. The optimal Cr(VI) concentration for growth was 5 mg/L, resulting in a growth rate of 1.17 cells/mL/day. Based on statistical analysis only concentration of Cr(VI) that affected C. vulgaris cell density and not the salinity. [ABSTRACT FROM AUTHOR]

Both rural and urban parts of the world, groundwater is an essential reservoir of freshwater Due to drainage and consequently rising pollution are a serious risk to the planet's ability to provide safe water supplies. For both health and medical practitioners, water that has been polluted by heavy metals-specifically, the elements cadmium, arsenic, nickel, copper, lead, manganese, and mercury-is developing a serious health risk. The main objective of this research was to evaluate the amount of heavy metals in the groundwater of the Kanker district in the Indian state of Chhattisgarh's Northern Bastar region. In the premonsoon period in May-June of the study region, samples were taken using manually operated pumps, tube wells, and dug wells at 15 distinct locations. The amount of each element, including Pb, Mn, Zn, and Fe, was measured with an atomic absorption spectrophotometer (AAS) and the appropriate digestion technique. The water samples had mean concentrations of metallic elements in an order: Fe>Pb>Zn>Mn. The outcome of this study was that the extent of accumulation of heavy metals in water samples is significantly greater than the recommended limitation, indicating that residents and the environment around them may be at risk. [ABSTRACT FROM AUTHOR]

The aim of the present research was to investigate the presence of heavy metals such as lead (Pb), copper (Cu), chromium (Cr), and cadmium (Cd) in blood samples from cows raised with irrigated wastewater, as well as in the wastewater itself, in the North-western region of Pakistan. A total of 60 blood samples were collected from five different locations in Kohat, namely Tappi Road (TR), Pindi Road (PR), Gul Malik Road (GMR), Markaz Road (MR), and a control group. The samples of both i.e. cow blood and wastewater were analyzed for the concentrations of heavy metals. The highest concentration of Cd was detected in the MR site with a mean value of 0.03 mg/L, and the highest concentration of Cu (0.04 mg/L) was recorded in the TR site, while the lowest level was found in the control group with a mean of 0.002 mg/L in blood samples. The highest Cr and Pb concentrations were found at the PR site, with mean values of 0.03 and 0.07 mg/L, respectively, whereas the control group had the lowest concentrations, with mean values of 0.002 and 0.01 mg/L. Similarly, heavy metal concentrations were analyzed in wastewater used for irrigation in the study area. Results indicated elevated concentrations of Cu and Cr in wastewater, although they remained below the World Health Organization (WHO) recommended values except for Cr (0.13 mg/L) in the GMR site, which exceeded permissible limits. Cd and Pb concentrations in wastewater were relatively low, but Cd concentration surpassed WHO limits, particularly with a mean concentration of 0.08 mg/L in the TR site. Comparison between heavy metal concentrations in blood and wastewater revealed higher values of Cd and Pb in blood samples than in wastewater, while Cu and Cr concentrations were higher in water compared to blood. Additionally, elevated levels of Super Oxide Dismutase (SOD), antioxidant enzyme Catalase (CAT), and oxidative stress marker malondialdehyde (MDA) were detected in blood samples. Cluster and principal component analyses were employed to assess heavy metal toxicity among the groups, indicating potential long-term adverse health effects on animals, transfer to humans, and toxicity in living organisms. [ABSTRACT FROM AUTHOR]

Porous materials are excellent candidates for water remediation in environmental issues. However, it is still a key challenge to design efficient adsorbents for rapid water purification from various heavy metal ions‐contaminated wastewater in one step. Here, two robust nitrogen‐rich covalent organic frameworks (COFs) bearing terpyridine units on the pore walls by a “bottom‐up” strategy are reported. Benefitting from the strong chelation interaction between the terpyridine units and various heavy metal ions, these two terpyridine COFs show excellent removal efficiency and capability for Pb2+, Hg2+, Cu2+, Ag+, Cd2+, Ni2+, and Cr3+ from water. These COFs are shown to remove such heavy metal ions with >90% of contents at one time after the aqueous metal ions mixture is passed through the COF filter. The nitrogen‐rich features of the COFs also endow them with the capability of capturing iodine vapors, offering the terpyridine COFs the potential for environmental remediation applications. [ABSTRACT FROM AUTHOR]

Natural and anthropogenic water pollution caused by heavy metals has become a major problem worldwide. As a result of these processes, many harmful heavy metals are mixed into the water and endanger the environment and human health. Therefore, this study aimed to investigate the hydrogeochemical properties of the stream waters of Göynük Canyon (Göynük Stream), which is located in southern Turkey, an important touristic region of Antalya. A total of 44 water samples were retained to evaluate the geochemical type, heavy metal contamination level, and suitability for drinking and irrigation of Göynük Canyon Stream waters. All samples were analysed by inductively coupled plasma mass spectrometry (ICP-MS), X-ray fluorescence (XRF), and multi-parameter portable water quality assessment. Analysed water samples were found to be of classes II and III in terms of overall water quality. The average hardness level is above the limit values. The results of geochemical analyses showed that the common water types in the region are Mg–Ca–HCO3, Ca–Mg–HCO3, Ca–Mg–HCO3–SO4, and Ca–Mg–HCO3–Cl-water facies. Most of the samples belong to the "rock weathering dominated" region represented in the Gibbs diagram. The hydrogen ion concentration (pH), electrical conductivity (EC), and total dissolved solids (TDS) values vary between respectively 6.5–7.9; 230.4–720.8 μS/cm, and 149–468 mg/L. Cations and anions followed the order Ca2+ > Mg2+ > Na+ > K+ and HCO3 − > SO42− > Cl− > F− > NO3 − . Heavy metal anomalies in water followed an increasing order: Cu < As < Pb < Ni < Ba < Fe < Cr < Mn < Zn < Sr. These heavy metals showed high index values (Poseidon index (PoS), contamination factor (CF), enrichment factor (EF), geochemical index (Igeo), heavy metals pollution index (HPI), contamination degree (Cd), in some water samples. There is a spatial anomaly in these locations related to limestone and ophiolite. This water can be used for irrigation purposes according to Wilcox, the United States salinity laboratory diagram (USSL), permeability index (PI), Kelly’s ratio (KR), and Residual Sodium Carbonate (RSC). [ABSTRACT FROM AUTHOR]

Sassoon docks is one of the oldest docks in Mumbai. It is one of the largest fish landing site in Mumbai. The dock gets untreated waste water and deteriorates the quality of seawater near the fish landing base. The dock is stench prominently emanated from the decayed fish and mishandled fish waste of shell fishes like prawns and shrimps. It is still active first wet docks. Heavy metals are found naturally which have high density and atomic weight. The heavy metal gets released through various agricultural industries, factories which cause severe effect on environment and as well as on organisms present in it. This can lead to multiple organ damage of organisms present in water. Heavy metals became strongly toxic as it gets mixed with water, soil. The microbial analysis of water can be determined through the present concentration of Escherichia coli, Coliforms. The bacterial count should not exceed more than 80 per 100 ml in sea water. The observed value is between 26 × 10³- 15 × 10³, 8.8 × 10³ _ 6.4 × 10³, 8.2 × 10³ _ 6.0 × 10³ for Total Bacterial Count, Coliforms, E.- Coli respectively. The bacterial count should be zero in any water. The observed value is much higher than the permissible limit which is due to the contamination and cause severe ill effects on marine organism and human as well as. The heavy metal get trapped in water due to release of industrial waste in the water. For different metals normal range differ from 0.001 to 0.1ml Excess presence of heavy metals deteriorate the various physiological processes. The Lead and Iron shows higher value i.e. 0.1 and 3.226, respectively. The heavy metals cause carcinogenic, tetragenic and mutagenic effects on organisms present in water. The three main source of dissolved iron sources are: sediments dissolution along continental margins, dust from the atmosphere and fluids from hydrothermal vents. High iron can accumulate in body of organism and can be fatal for them. [ABSTRACT FROM AUTHOR]

Purpose. To assess the impact of mining waste on the heavy metal content of water surfaces, plants, and topsoil near the tailings dam of a Zn-Pb mine using both biotests and analytical methods. Methodology. A battery of microbiotests on different animal and plant species was carried out, making it possible to evaluate the toxic effect of residues and surrounding soils on living organisms. Furthermore, the possible relationship between the observed toxicity and the results of the physicochemical analysis of the samples was studied. Findings. The tests showed that the topsoil in contact with the tailings dam is slightly toxic to the living organisms used while the mining tailings are toxic or even very toxic. The heavy metal content of the samples is particularly high for Fe, Zn, Pb and Cu. The correlation of physic-chemical parameters and the results of microbiotests using the principal components analysis (PCA) and the multiple correspondence factor analysis (MCFA) indicate that the toxicity of tailings and the surrounding topsoil can be associated with anthropogenic mining activity. Originality. The study aimed to assess the impact of mining waste on the heavy metal content using biotests and analytical methods. The evaluation considers the concentrations of the samples (highly concentrated samples and samples after dilution) and the different phases of exposure (solid, liquid) for a more detailed assessment of the potential toxicity of the samples. Practical value. It is important to conduct a comprehensive assessment of mining waste and the risks it may pose to humans and the environment in order to develop an adequate rehabilitation plan. [ABSTRACT FROM AUTHOR]

The rapid industrial development in the Indian capital region has led to significant waste generation, which, despite undergoing treatment prior to disposal, contributes substantially to water body contamination. Given the diverse nature of these wastes and their potential repercussions across the food chain, a study was conducted to evaluate heavy metal contamination levels in the Ganga and Yamuna Rivers of two major cities. Six heavy metals (Pb, Cd, Hg, Cu, Cr, and Zn) were analyzed in fish, water, and sediment samples by utilizing flame atomic absorption spectrophotometry (Avanta Σ) from March 2019 to February 2020. Results revealed distinct heavy metal distribution patterns, with Cr > Zn > Pb > Cu > Cd > Hg in the Ganga River and Zn > Cr > Pb > Cu > Cd > Hg in the Yamuna River for fish samples. Additionally, levels of Hg in Cyprinus carpio and Sperata oar from the Ganga River, and Pb, Cd, Hg, and Cr in Salmophasia bacaila and Mystus cavasius from the Yamuna River exceeded WHO/FAO permissible limits. In water samples, the predominant heavy metal sequences were Pb > Cu > Zn > Cr > Cd > Hg for the Ganga River and Cr > Zn > Pb > Cu > Cd > Hg for the Yamuna River, with Pb, Cr, Zn, and Cd surpassing WHO standards. Sediment analysis revealed varying heavy metal compositions, with Zn > Cr > Pb > Cu > Cd > Hg in the Ganga River and Cr > Zn > Pb > Cu > Cd > Hg in the Yamuna River. While drinking water and fish from the Ganga River were deemed safe for consumption, those from the Yamuna River were not. Given the toxic nature of heavy metals and their detrimental health impacts, regular monitoring and effective management strategies are imperative. [ABSTRACT FROM AUTHOR]

Copper ions in wastewater present substantial environmental hazards, toxic to aquatic species and prone to bioaccumulation. Addressing this, we present a novel cross‐linked polythiourethane (C‐PTU) as a promising chelating adsorbent for the effective removal of copper ions from wastewater. A new monomer, 5‐(2,2,2‐trifluoroacetamide) benzene‐1,3‐bis(carbonyl) isothiocyanate (TFA‐ITC), was synthesized and further condensed with a 1,4‐butane diol to produce a trifluoroacetamide functionalized polythiourethane (TFA‐PTU) and subsequently generating amine functionalized polythiourethane (A‐PTU). The cross‐linking reaction was carried out through amino groups present on the polymer backbone with terephthaloyl chloride, resulting in the formation of C‐PTU. The monomer and polymers underwent characterization using Fourier transform infrared, 1H, and 13C nuclear magnetic resonance spectroscopy, with X‐ray diffraction analyzing the resin's chain alignment. Thermogravimetric and differential scanning calorimetry assessed C‐PTU's thermal properties. The adsorption process for Cu(II) ions was studied using atomic absorption spectroscopy, optimizing conditions for maximal uptake. Results revealed that C‐PTU exhibited a significant adsorption capacity for Cu(II) ions, reaching 67% after a 2 h contact time, with optimal adsorption occurring at pH 6. The Langmuir adsorption isotherm described the sorption mechanism, indicating favorable monolayer cation adsorption via coordination with donor sites on C‐PTU. This research presents a viable solution for copper ion contamination in wastewater, illustrating C‐PTU as an efficient, environmentally friendly adsorbent, marking progress toward cleaner water resources. [ABSTRACT FROM AUTHOR]

Global advancement of solar energy and its emerging technologies are good indicators to assess the general response of energy users to clean energy as enshrined in the sustainable development goal (SDG) 7. However, the reality that solar panels and other components would become electronic waste someday and ultimately contribute to chemical hazards in the environment is a source of concern. This study aimed to evaluate the amounts of heavy metals in solar photovoltaic (PV) modules using atomic absorption spectroscopy and estimate the health risks associated with these heavy metals. Six samples of solar PV were collected and evaluated for Chromium (Cr), Cadmium (Cd), Lead (Pb), and Arsenic (As). Using the health risk index (HRI) and the target hazard quotient (THQ), the human dangers presented by the presence of heavy metals were evaluated. The heavy metal content ranged as follows: Pb (6.00–6.25 mg/kg); Cd (0.10–1.25 mg/kg); Cr (8.00–12.00 mg/kg); and As (0.60–1.25 mg/kg). An estimate of the average weight for children and adults was used to calculate the health risk index. The result showed that health risks for children and adults are high with heavy metal concentrations escalating in the order Pb > Cd > Cr > Ar. The THQ in all metals was < 1 in all the solar PV samples, which indicates they do not pose serious health risk concerns in a single panel. However, considering the large number of waste panels, the risk would be significant. Also, it was found that there were naturally occurring radioactive materials (NORM) in the PV modules and their effects are more in the short term. Hence, heavy metals are envisaged as long-term hazards, and NORM in PV modules are envisaged as short-term hazards. Using the EPA dose compliance concentrations (DCC) (EPA-DCC), the radioactive exposures from the selected photovoltaics were proven to be directly dependent on the number of PVs in use and their distance from the PV installations. Several recommendations were made to curb death in the process of pursuing cleaner energy technologies. [ABSTRACT FROM AUTHOR]

With the rapid development of electronics, the application and research of two-dimensional materials have been at the forefront of the world's scientific research. Black phosphorus (BP) has the advantages of large specific surface area, anisotropy, band tunability, high electrical conductivity and high theoretical specific capacity, which make it very promising for research in the fields of medicine, aerospace and electrochemistry. This paper calculates the electronic structure and adsorption properties of BP in water for different heavy metal ions of Pb 2 + , Hg 2 + and Cd 2 + , including adsorption energy, bandgap, electron density and Mulliken population analysis, based on the first-principles approach of density generalized theory. First principles are quantum mechanical calculations based on density functional theory (DFT), which is a dominant well-developed method in the field of materials simulations, with low errors and high efficiency, especially in systems containing metallic particles. The results showed that the Pb 2 + adsorption system in water was more stable than the Hg 2 + adsorption system and the Cd 2 + adsorption system. The bandgap values of 0.617, 0.785 and 0.715 eV of BP after adsorption of Pb 2 + , Hg 2 + and Cd 2 + in water are smaller compared to 0.891 eV of intrinsic BP, and its properties change from direct bandgap semiconductor to indirect bandgap semiconductor. The higher the stability of a system for the adsorption of different heavy metal ions by BP, the higher the internal electron activity of the adsorption system and the amount of electron transfer. Meanwhile, it is concluded that the electrons mainly transfer from P to heavy metal ions in all the adsorption systems. The electron transfer of the BP-Pb 2 + , Hg 2 + , and Cd 2 + adsorption system occurs mainly in the p, s, and s/p orbitals, respectively. The above content investigated the electronic structure changes and internal electron transfer of heavy metal ions adsorbed by black phosphorus in water, expecting to provide a new reference basis for the detection of heavy metal ions in industrial wastewater using black phosphorus. [ABSTRACT FROM AUTHOR]

Novel functionalized and/or grafted crosslinked chitosan adsorbents were synthesized and used to remove several toxic heavy metal ions such as nickel, lead, chromium, and cadmium ions from contaminated water. The chitosan biopolymer was functionalized by maleic anhydride (CS_MA) acting also as a crosslinking agent. Glutaraldehyde-crosslinked chitosan (CS_GA) grafted with poly(methyl methacrylate) (CS_MMA) was also synthesized. The synthesized adsorbents were characterized using a variety of analytical techniques such as SEM, TGA, and FTIR, which confirmed their chemical structures and morphology. The adsorption capacity of the adsorbents was analyzed under various conditions of contact time, adsorbent dose, initial concertation, temperature, and pH and evaluated against those of pure chitosan (CS) and the crosslinked chitosan(CS_GA). The ultimate removal conditions were 0.5 g/100 mL adsorbent dose, an initial metal ion concentration of 50 ppm, a temperature of 45 °C, and pH 9. CS_MMA had the highest removal percentages for all metal ions, ranging from 92% to 94%. The adsorption was demonstrated to fit a pseudo-first-order model that followed a Langmuir adsorption isotherm. The results highlight the capacity of the synthesized polymers to efficiently remove major toxic contaminants at low cost from contaminated water, present especially in low-income areas, without harming the environment. [ABSTRACT FROM AUTHOR]

The current study reveals the concentration of heavy metals in sediment, water, and three fish species of the Korotoa River in Bangladesh. Two diverse seasons, namely wet (August–September 2021) and dry (January–February 2022) were chosen to compare the seasonal differences of five concerning heavy metals (Cr, Co, Pb, As, and Cd) adjacent to coal mining area using inductively coupled plasma mass spectrometry. Different physicochemical parameters of water quality along with the concentration of heavy metals varied significantly with the seasons. However, the average concentrations of the examined heavy metals followed the downward order of Cr > Pb > As > Co > Cd for both wet and dry seasons. The mean concentration of heavy metals in fish was found higher in Mastacembelus armatus compared with Labeo bata and Amblypharyngodon mola. The values of the researched heavy metals' enrichment factors were reported in the following order: As > Co > Cr > Cd. The pollution load index (PLI) specified that the sediment of the river under study was not seriously contaminated (PLI <1). However, the content of heavy metals in the water was discovered to be much greater than the standards for safe drinking water limits and the preservation of freshwater aquatic life, demonstrating that the river water from this area is unsafe for use as drinking water or for cooking. However, the study suggests relevant authorities should take necessary action to stop further pollution in the study area. [ABSTRACT FROM AUTHOR]

Coal mining is a vital industrial activity but often associated with negative environmental effects, including the accumulation of waste containing heavy metals in tailings dump. These heavy metals, such as lead, chromium, copper, zinc, cadmium, mercury, and others, pose significant risks to the environment and human health. The mobility of these heavy metals is a major concern, as they can be released into soil and water during rain or erosion processes, contaminating water sources and affecting aquatic and terrestrial life. These metals can be taken over by plants and eventually end up in the trophic chain, including in humans. The toxicity of heavy metals is well known, with these substances having harmful effects on human health. In this paper, the main ways of transferring heavy metals into environmental components and their spatial distribution from sterile holes to water and soil environment components. As a case study, the sterile Balomir hole, an inactive hole for about 9 years resulting from the exploitation of the hule from the Uricani mine located in the Jiu Valley. [ABSTRACT FROM AUTHOR]

Vegetable cultivation under sewage irrigation is a common practice mostly in developing countries due to a lack of freshwater. Long-term usage provokes heavy metals accumulation in soil and ultimately hinders the growth and physiology of crop plants and deteriorates the quality of food. A study was performed to investigate the role of brassinosteroid (BRs) and silicon (Si) on lettuce, spinach, and cabbage under lead (Pb) and cadmium (Cd) contaminated sewage water. The experiment comprises three treatments (control, BRs, and Si) applied under a completely randomized design (CRD) in a growth chamber. BRs and Si application resulted in the highest increase of growth, physiology, and antioxidant enzyme activities when applied under canal water followed by distilled water and sewage water. However, BRs and Si increased the above-determined attributes under the sewage water by reducing the Pb and Cd uptake as compared to the control. It's concluded that sewerage water adversely affected the growth and development of vegetables by increasing Pb and Cd, and foliar spray of Si and BRs could have great potential to mitigate the adverse effects of heavy metals and improve the growth. The long-term alleviating effect of BRs and Si will be evaluated in the field conditions at different ecological zones. Numerous studies evaluated the effect of Brassinosteroid (BRs) and Silicon (Si) to mitigate heavy metal stress in vegetables through soil application. However, research on the foliar application of both BRs and Si to improve vegetable growth under heavy metal stress is very limited. Moreover, most researchers used only a single source of irrigation water but in our study, three different water sources including distilled water (CW), canal water (CW), and sewage water (SW) were used to evaluate their impact on growth, physiology, and antioxidant activities of leafy vegetables. In this way, this study could be the first in terms of specific vegetable crops (lettuce, spinach, and cabbage) and evaluated for their growth and development performance and antioxidant activities under three different types of irrigation sources with foliar application of BRs and Si. Brassinosteroid and Silicon improved the growth of leafy vegetables. Sewage water hindered the growth and physiological parameters of lettuce, spinach, and cabbage. Brassinosteroid and Silicon mitigated the heavy metal-induced stress in leafy vegetables. [ABSTRACT FROM AUTHOR]

An electrode modified with phytic acid (PA)-doped polypyrrole (PPy)/molybdenum disulfide (MoS2) nanocomposites for the simultaneous detection of Pb2+ and Cd2+ heavy metal ions in water. On the surface of MoS2 nanosheets PA-doped PPy/MoS2 nanomaterials were fabricated by in situ chemical oxidation polymerization. The PA-doped PPy network was uniformly covered the surface of MoS2 nanosheets which can improve stability of MoS2 and increase electrochemical active sites. The PA-doped PPy/MoS2-modified electrode demonstrated outstanding electrochemical performance compared to the PA-doped PPy and MoS2-modified electrodes. The PA-doped PPy/MoS2 has been proven to detect range of Pb2+ and Cd2+ between 10 and 300 μg/L. The limit of detection (LOD = 3σ/k) for Pb2+ was 1.78 μg/L and for Cd2+ was 2.03 μg/L. The PA-doped PPy/MoS2-modified electrode has good selectivity, reproducibility and stability. In practical tap water applications, good recoveries were achieved. This work illustrated a straightforward, helpful and high performing pathway within the areas of electrochemical detecting Pb2+ and Cd2+. [ABSTRACT FROM AUTHOR]

Numerous technologies for cleaning the environment without producing hazardous waste products have arisen in response to the rise in environmental pollution. Industrialization and the growing population have put society to a hard test. Continuous discharge of heavy metals (chromium, nickel, copper, mercury etc.) in water bodies is increasing by anthropogenic activities; these cause bio accumulation and shift towards a resistant microbial community. These hazardous metals enter the human body through water and food, creating a slew of health issues. Chromium (VI) is one such toxic pollutant and is more toxic than chromium (III). Several environment‐friendly technologies have been developed for decontaminating wastewater by using microorganisms. Microalgae, cyanobacteria, bacteria and fungi are used for heavy metals eradication from the water due to their metal tolerance, bioaccumulation and biotransformation capacity. In this study two cyanobacteria strains were compared for their physiological response and metal tolerance for Cr (VI) stress. Leptolyngbya lignicola and Phormidium tenue were grown in a medium containing various concentrations of chromium (1 ppm, 2 ppm, 3 ppm, 4 ppm, 5 ppm, and 10 ppm), and biochemical parameters (chlorophyll, carotenoids, protein, proline, amino acid, carbohydrate, reducing sugar and lipid content) were measured. The findings revealed that P. tenue was more sensitive to metal stress than L. lignicola. P. tenue showed a decreasing trend for all biochemical parameters except proline at higher ad lower doses of Cr (VI) stress. However L. lignicola showed an increase in biomass (6.09%) and other biochemical parameters over control at lower metal stress concentration (1 ppm), whereas, a gradual decrease in all parameters except proline was observed at higher concentrations. Further L. lignicola showing high tolerance index can be preferred for metal remediation from the water bodies of heavy metal contaminated area. [ABSTRACT FROM AUTHOR]

Kathajodi, the principal southern distributary of the Mahanadi River, is the vital source of irrigation and domestic water use for densely populated Cuttack city which receives anthropogenic wastes abundantly. This study assesses the contamination level and primary health status of urban wastewater, and its receiving river Kathajodi based on the physicochemical quality indices employing inductively coupled plasma mass spectroscopy and aligning with guidelines from the United States Environmental Protection Agency (USEPA) and WHO. The high WQI, HPI, and HEI in the catchment area (KJ2, KJ3, and KJ4) indicate poor water quality due to the influx of domestic waste through the primary drainage system and effluents of healthcare units. A high BOD (4.33–19.66 mg L−1) in the catchment indicates high organic matter, animal waste, bacteriological contamination, and low DO, resulting in deterioration of water quality. CR values beyond limits (1.00E − 06 to 1.00E − 04) in three locations of catchment due to higher Cd, Pb, and As indicate significant carcinogenic risk, while high Mn, Cu, and Al content is responsible for several non-carcinogenic ailments and arsenic-induced physiological disorders. The elevated heavy metals Cd, Cu, Fe, Mn, Ni, and Zn, in Kathajodi, could be due to heavy coal combustion, vehicle exhaust, and industrial waste. On the other hand, Cu, Fe, K, and Al could be from agricultural practices, weathered rocks, and crustal materials. Positive significant (p ≤ 0.05) Pearson correlations between physicochemical parameters indicate their common anthropogenic origin and similar chemical characteristics. A strong correlation of PCA between elements and physiological parameters indicates their role in water quality deterioration. Assessing the surface water quality and heavy metal contents from this study will offer critical data to policymakers for monitoring and managing public health concerns. [ABSTRACT FROM AUTHOR]

Groundwater and surface water quality is of great significance for humanity as they serve as the primary drinking water sources globally. Due to population growth and the need to provide people with necessities that depend on water as an essential resource, these bodies of water are becoming more polluted. The present study involved the collection of groundwater and surface water samples from Kampala and Mbarara districts in Uganda during the dry and wet seasons. Also, concentrations of lead (Pb), manganese (Mn), cadmium (Cd), copper (Cu), and iron (Fe) were analyzed in order to evaluate the toxicity of metals, identify potential sources, and determine the health risk associated with their presence in water. Results showed that metals were observed with higher concentration during the wet season than the dry season. The concentrations of Fe (8.646 ± 0.00 mg/L), Mn (2.691 ± 0.01 mg/L) and Cd (0.090 ± 0.41 mg/L) measured in groundwater were significantly higher than those measured in surface water. However, only Cu was observed with higher concentration (0.322 ± 0.06 mg/L) in surface water during the wet season. Furthermore, the degree of contamination (Cd) and the heavy metal pollution index (HPI) were evaluated for both the wet and dry seasons. Results showed that few samples were found in the category of portable drinking water while majority are within the "poor" and "very poor" classes which require proper treatment before consumption. The oral hazard index (HIoral) results showed that none of the samples are suitable for consumption; therefore, cause potential non-carcinogenic health issues to the consumer (HIoral > 1). Moreover, children are more at risk than adults in the study districts (higher HI values in both seasons). This study recommends frequent monitoring of quality of water and also effluent waste treatment by the major source of pollution. [ABSTRACT FROM AUTHOR]

Among the many heavy metal pollution treatment agents, carbonate materials show strong flexibility and versatility by virtue of their high adsorption capacity for heavy metals and the characteristics of multiple and simple modification methods. It shows good potential for development. This review summarizes the application of carbonate materials in the treatment of heavy metal pollution according to the research of other scholars. It mainly relates to the application of surface-modified, activated, and nano-sized carbonate materials in the treatment of heavy metal pollution in water. Natural carbonate minerals and composite carbonate minerals solidify and stabilize heavy metals in soil. Solidification of heavy metals in hazardous waste solids is by MICP. There are four aspects of calcium carbonate oligomers curing heavy metals in fly ash from waste incineration. The mechanism of treating heavy metals by carbonate in different media was discussed. However, in the complex environment where multiple types of pollutants coexist, questions on how to maintain the efficient processing capacity of carbonate materials and how to use MICP to integrate heavy metal fixation and seepage prevention in solid waste base under complex and changeable natural environment deserve our further consideration. In addition, the use of carbonate materials for the purification of trace radioactive wastewater and the safe treatment of trace radioactive solid waste are also worthy of further exploration. [ABSTRACT FROM AUTHOR]

Research on heavy metal pollution in horticultural farms located around lakes in the Central Ethiopian Rift Valley Region has focused on measuring the levels of heavy metals and their health implications. However, the ecological risks of horticultural farms contaminated with heavy metals in this region have not been studied. The current study addresses this gap by providing information on the degree of heavy metal contamination and the ecological risk associated with horticultural farms around Lake Ziway, using various pollution indices. An inductively coupled plasma optical emission spectrometer (ICP‐OES) was used to measure the concentrations of nine heavy metals (As, Cd, Co, Cu, Cr, Ni, Pb, Hg, and Zn) in a total of 30 composite soil and irrigation water samples, each consisting of a mix of six subsamples. The results indicated that the mean concentrations of Hg, Cd, Pb, and Zn in soils collected from all the sampling sites exceeded the FAO/WHO maximum permissible limit (MPL). The values of both the contamination factor (CF) and contamination degree (Cd) of the heavy metals ranged from 0.04 to 2.66 and 2.81 to 6.14, respectively, indicating a low to medium level of contamination for both indices. The pollution load index (PLI) values of 0.451, 0.449, and 0.157 for sites 2, 1, and 3, respectively, indicate "unpolluted" to "moderately polluted" levels of heavy metal pollution. However, the ecological risk indices (ERIs) at sites 2 and 1 (158.92 and 141, respectively) showed a potentially high ecological risk due to soil pollution. Therefore, close monitoring and early intervention mechanisms must be in place to control pollution in the study area. [ABSTRACT FROM AUTHOR]

Lake Qaroun, one of Egypt’s largest lakes, is a remnant of a much larger one; it is considered as a closed basin used as a general reservoir for agricultural wastewater drainage in El-Fayoum Province. Furthermore, the lake receives agricultural and partially treated sewage water from the El-Fayoum Governorate as well as fish farm drainage. The current study assessed the changes in physicochemical characteristics and heavy metal levels (Zn, Pb, Cd, and Cu) in water and sediment, as well as the bioaccumulation of these heavy metals in Mugilcephalus fish samples obtained from Lake Qaroun. Thus, information on histopathological changes in the gills, liver, kidney, end of the alimentary canal, and muscles was provided. This research was conducted in three different locations along Lake Qaroun (Eastern, southeastern, and western). This study confirms an increased heavy metal pollution in the eastern and southeastern sectors of Lake Qaroun, facing the drain outlet, as a result of the discharge of drainage water effluents without prior treatment, which directly affects water quality and fish health, and subsequently human health. The concentrations of Pb and Cd in the water exceeded the allowable limits. The gills are the target organ for Cd in Mugil cephalus, but Pb and Zn are preferentially collected in the kidneys, with the liver containing the highest concentrations of Cu ions. Histopathological changes with an evident damage were visible in the gills, liver, and kidneys of Mugil cephalus taken from the lake’s eastern and southeastern areas. In addition, blood parameters of Mugil cephalus collected from various study sites throughout Lake Qaroun were included in this study. A highly significant decrease was detected in red blood cell counts, hemoglobin content, and hematocrit values of fish collected from the lake's eastern and southeastern parts in comparison to fish collected from the western sector, indicating more or less normal values. [ABSTRACT FROM AUTHOR]

Monitoring the quality of tap water in the distribution system and the ability to estimate the risk of losing its sanitary safety is an important aspect of managing the collective water supply system. During monitoring, the physical, chemical, and biological stability of water was assessed, which is the main determinant ensuring the appropriate quality of water for consumers. The physicochemical and microbiological quality of water was analyzed for two distribution systems (DSs), including the analysis of heavy metals (Zn, Fe, Mn, Cr, Ni, Cu, Cd, Pb). The tests carried out showed that in both distribution systems, the water supplied to consumers met the guidelines for water intended for human consumption. It can be considered that the risk of uncontrolled changes in water quality in DSs with an average water production of <10,000 m3/d and the length of water pipelines < 150 km is very low. The water introduced into the system differed in the place of water intake and water purification technology, which influenced the final water quality. In DS(II), higher values were recorded for hardness, conductivity, calcium, alkalinity, nitrates, and DOC. It was found that the content of heavy metals during water transport to the consumer increased in the case of DS(I) for Zn, Ni, Cu, Cd, and Pb, and in the case of DS(II) for Fe, Mn, Ni, Cu, Cd, and Pb. The observed differences resulted from the different quality of the intake water as well as from different materials used to build internal installations and their age and technical condition. The analyzed tap water was characterized by physical and chemical stability. However, the water did not meet the guidelines for water biostability due to the increased content of biogenic substances. [ABSTRACT FROM AUTHOR]

This study investigated the concentrations of heavy metals in the water sources of the upstream region of the Huangpu River, the Yangtze River Estuary, and various areas in Shanghai, as well as the heavy metal concentrations in the blood of Shanghai residents. It aimed to analyze the heavy metal elements absorbed by the human body and the resulting pathological effects. The results revealed that surface water primarily contains five heavy metals: copper (Cu), lead (Pb), zinc (Zn), arsenic (As), and mercury (Hg), while water sediments primarily contain seven heavy metals: Cu, cadmium (Cd), Pb, chromium (Cr), Zn, As, and Hg. The main heavy metals present in the human body are Pb, Hg, As, and Cd. By reviewing previous articles, it was found that heavy metal concentrations in human blood are higher than those in surface water, suggesting uncertainties in the heavy metal content of surface water and its tendency to settle at the bottom. Furthermore, a comparison of heavy metal content in sediments revealed that Hg is the most readily absorbed heavy metal by the human body and is also a toxic environmental pollutant. Within the cell, Hg is highly toxic to mitochondria and may cause oxidative stress and neurodegenerative disease. This study concludes that water sediments serve as the major source of pollution in the human body and pose significant health risks, thereby necessitating the implementation of effective preventive measures. [ABSTRACT FROM AUTHOR]

Accumulation of bioavailable heavy metals in aquatic environment poses a serious threat to marine communities and human health due to possible trophic transfers through the food chain of toxic, non-degradable, exogenous pollutants. Copper (Cu) is one of the most spread heavy metals in water, and can severely affect primary producers at high doses. Here we show a novel imaging test to assay the dose-dependent effects of Cu on live microalgae identifying stress conditions when they are still capable of sustaining a positive growth. The method relies on Fourier Ptychographic Microscopy (FPM), capable to image large field of view in label-free phase-contrast mode attaining submicron lateral resolution. We uniquely combine FPM with a new multi-scale analysis method based on fractal geometry. The system is able to provide ensemble measurements of thousands of diatoms in the liquid sample simultaneously, while ensuring at same time single-cell imaging and analysis for each diatom. Through new image descriptors, we demonstrate that fractal analysis is suitable for handling the complexity and informative power of such multiscale FPM modality. We successfully tested this new approach by measuring how different concentrations of Cu impact on Skeletonema pseudocostatum diatom populations isolated from the Sarno River mouth. [ABSTRACT FROM AUTHOR]

In view of water and soil getting polluted by Pb(II), Zn(II), and other heavy metals in tailings and acid mine drainage (AMD), we explored the removal effect of sulfate-reducing bacteria (SRB) on Pb(II), Zn(II), and other pollutants in solution and tailings based on the microbial treatment technology. We used the scanning electron microscope-energy dispersive spectroscopy (SEM-EDS), X-ray diffraction (XRD), and X-ray fluorescence (XRF), to reveal the mechanism of SRB treatment of tailings. The results showed that SRB had a strong removal capacity for Zn(II) at 0-40 mg/L; however, Zn(II) at 60-100 mg/L inhibited the growth of SRB. Similarly, SRB exhibited a very strong ability to remove Pb(II) from the solution. At a Pb(II) concentration of 10-50 mg/L, its removal percentage by SRB was 100%. SRB treatment could effectively immobilize the pollutants leached from the tailings. With an increase in the amount of tailings added to each layer, the ability of SRB to treat the pollutants diminished. When 1cm of tailingssand was added to each layer, SRB had the best effect on tailing sand treatment. After treatment, the immobilization rates of SO2-4, Fe(III), Mn(II), Pb(II), Zn(II), Cu(II), and total Cr in the leachate of #1 tailing sand were 95.44%, 100%, 90.88%, 100%, 96.20%, 86.23%, and 93.34%, respectively. After the tailings were treated by SRB, although the tailings solidified into a cohesive mass from loose granular particles, their mechanical strength was <0.2 MPa. Desulfovibrio and Desulfohalotomaculum played the predominant roles in treating tailings by mixing SRB. The S2- and carbonate produced by mixing SRB during the treatment of tailings couldmetabolize sulfate by combining with the heavymetal ions released by the tailings to form FeS, MnS, ZnS, CuS, PbS, Cr2S3, CaCO3, MnCO3, and other precipitated particles. These particles were attached to the surface of the tailings, reducing the environmental pollution of the tailings in the water and soil around the mining area. [ABSTRACT FROM AUTHOR]

Water quality continues to be the challenge to residents in Dar es Salaam due to various anthropogenic activities in the city. This study was conducted to assess groundwater quality by determining concentrations of heavy metals. Both probability and Nonprobability sampling techniques were used to collect samples from 40 groundwater wells in 24 wards of Temeke municipal and analysed using Microwave Plasma Atomic Emission Spectrometer (Agilent 4210 MP-AES) at the Geochemistry Laboratory of the University of Dar es Salaam. Results indicated varying heavy metal concentrations ranging from 0.71 ± 0.08 to 6.64 ± 0.21 mg/l for As, 0.02 ± 0.01 to 0.07 ± 0.01 mg/l for Co and 0.16 ± 0.01 to 0.02 ± 0.01 mg/l for Pb. The As, Co and Pb concentrations exceeded (P < 0.05) the recommended TBS standards of 0.05 mg/l, 0.003 mg/l and 0.01 mg/l respectively. Other concentrations ranged from 0.01 ± 0.01 to 0.88 ± 0.01 mg/l for Cu, 0.02 ± 0.01 to 3.55 ± 0.02 mg/l for Fe, 0.00 ± 0.00 to 4.63 ± 0.03 mg/l for Mn and 0.01 ± 0.01 to 3.00 ± 0.01 mg/l for Zn. The Cu, Fe, Mn and Zn concentrations were below (P > 0.05) the allowable TBS limits of 0.05 mg/l, 0.3 mg/l, 0.1 mg/l and 3 mg/l respectively. Health risk analysis revealed potential adverse health effects from long term consumption of As, Mn and Pb with Hazard Quotient exceeding 1 (HQ > 1). The Hazard Index (HI) for all groundwater samples was also above 1 (HI > 1) indicating a higher likelihood of adverse health effects. The study concluded that groundwater wells in Temeke Municipal are affected through natural and anthropogenic activities leading to high levels of heavy metal concentrations. Also, this study provides valuable information on risk associated by continued usage of groundwater in Temeke region and hence informs respective stakeholders on groundwater quality and potential risks thereby emphasizing the need for remedial measures and stricter regulations to safeguard public health. The study recommends the need for regular groundwater quality and safety monitoring to assess the levels of heavy metals concentrations and implement sustainable groundwater management strategies to address the increasing water demand in Temeke municipal, Dar es Salaam. [ABSTRACT FROM AUTHOR]

Anthropogenic impacts and the accumulation of heavy metals in water bodies have increased significantly as a result of increased urbanisation, endangering both aquatic biota and human health. The pace of urbanisation and its attendant freshwater ecosystem pollution in Nigeria is so fast that there are concerns for the nation's freshwater biota. To this end, six heavy metals were investigated in the water column, sediment, and tissues of macroinvertebrate functional feeding guilds (FFGs) of a Nigerian stream. Three heavy metals that are non-essential (As, Cd, and Pb) exceeded their WHO permissible limits for surface fresh waters. According to the geo-accumulation index (Igeo) and contamination factor (CF) used to assess heavy metal pollution, there was a high level of Cd contamination among all heavy metals found in the sediment. These heavy metals were all biomagnified (>1), especially among the predators. The study concluded that Opa Stream was moderately impacted based on the concentrations of heavy metals in the stream's water column, sediment, and macroinvertebrate tissues. Future research works can consider the remediation of heavy metals that are non-essential in freshwater systems to ensure the sustainability of freshwater biodiversity and human health. [ABSTRACT FROM AUTHOR]

The objectives of the study were to (1) identify and measure the concentration of five toxic elements in the Tigris water, (2) determine the threat of these metals in water by various pollution indices such as pollution index (PI) as single index, metal index (MI) as integrated index, and potential ecological risk index (PERI) to assess the ecological risk. The results of this study showed that PI values for most elements were at nonaffected levels, except for Pb and Al metals, which were within slight and moderate levels, respectively. Whereas MI values indicate that all sites fall within a threshold of warning level. For the contamination factor, the values mostly lie in the low contamination level, except Al lies within the moderate range, which led to an increase in the contamination degree. For risk assessment, the values of ecological risk factors for all metals at all sites were within a low-risk level, less than 40. Also, the values of the ecological risk index in all sites were at a low-risk level, recorded at 17.70, 22.92, 22.62, and 21.79 in sites 1, 2, 3, and 4, respectively. We can conclude that the decrease in the levels of Er led to a decrease in the levels of PERI and vice versa. [ABSTRACT FROM AUTHOR]

Studies have investigated heavy metal (HM) contamination in the Bohai Sea, but primarily in seawater and associated sediments, or in single rivers. For the first time, 31 major rivers discharging into the Bohai Sea were analyzed, along with 27 uniformly distributed coastal seawater samples and selected invertebrates. The elements measured were As, Cd, Cr, Cu, Ni, Pb, V, and Zn. We calculated the 'geo-accumulation index', the 'metal enrichment factor', and the 'contamination factor', coupled with the 'pollution load index', and our findings suggested low-grade HM pollution, although two conspicuous associations of elements were found to stand out in particular: One is a combination of As, Cu, Cr, and V in seawater samples that may indicate pollution from intensive ship traffic. The other shows a significant pattern of Cr, Pb, and Zn in water samples from rivers discharging between Yantai and Weihai on the Shandong Peninsula at the south edge of the Bohai Sea. This is primarily a farming area, with a moderate share of industrial enterprises. Investigations including fertilizers and pesticides point to agricultural practices and textile printing/chrome tanneries as the causes of contamination. Overall, a significant decline was found in the HM load in the rivers, apart from those discharging into the Yellow Sea section. [ABSTRACT FROM AUTHOR]

Heavy metals are naturally omnipresent in aquatic systems. Excess amounts of heavy metals can accumulate in organisms of pollution impacted systems and transfer across a food web. Analysing the food web structure and metal contents of the organisms can help unravel the pathways of biomagnification or biodilution and gain insight in trophic linkages. We measured heavy metals and other elements in mussel bank detritus and organisms of the Biesbosch reservoirs (the Netherlands) and linked those to stable isotopic signatures. The heavy metal contents (cadmium, copper, lead, and zinc) were often lowest in benthivorous, omnivorous and piscivorous species (mainly fish); whereas, phosphorus contents were lower in the autotrophs. Mussel bank detritus contained the highest amounts of heavy metals. The heavy metals were negatively correlated with δ15N values. For selenium no clear trend was observed. Furthermore, there was a negative correlation between fish length and some heavy metals. Based on all 20 analysed elemental contents, similarities between species became apparent, related to niche or habitat. This study confirms that elemental contents of species can differ between feeding guilds and/or species, which can be attributed to metabolic and physiological processes. The organisms in higher trophic levels have adaptations preventing metal accumulation, resulting in lower contents. Within the fish species biodilution occurs, as most metal contents were lowest in bigger fish. Overall, the metals did not seem to biomagnify, but biodilute in the food web. Metal analyses combined with isotopic signatures could thus provide insights in metal transfer and possible trophic linkages within a system. [ABSTRACT FROM AUTHOR]

Monitoring antibiotic retention in human body fluids after treatment and controlling heavy metal content in water are important requirements for a healthy society. Therefore, the approach proposed in this study is based on developing new optical sensors using porphyrin or its bifunctional hybrid materials made with AuNPs to accomplish the accurate detection of chloramphenicol and cobalt. To produce the new optical chloramphenicol sensors, 2,7,12,17-tetra-tert-butyl-5,10,15,20-tetraaza-21H,23H-porphine (TBAP) was used, both alone in an acid medium and as a hybrid material with AuNPs in a water–DMSO acidified environment. The same hybrid material in the unchanged water–DMSO medium was the sensing material used for Co2+ monitoring. The best results of the hybrid materials were explained by the synergistic effects between the TBAP azaporphyrin and AuNPs. Chloramphenicol was accurately detected in the range of concentrations between 3.58 × 10−6 M and 3.37 × 10−5 M, and the same hybrid material quantified Co2+ in the concentration range of 8.92 × 10−5 M–1.77 × 10−4 M. In addition, we proved that AuNPs can be used for the detection of azaporphyrin (from 2.66 × 10−5 M to 3.29 × 10−4 M), making them a useful tool to monitor porphyrin retention after cancer imaging procedures or in porphyria disease. In conclusion, we harnessed the multifunctionality of this azaporphyrin and of its newly obtained AuNP plasmonic hybrids to detect chloramphenicol and Co2+ quickly, simply, and with high precision. [ABSTRACT FROM AUTHOR]

The presence of heavy metals and/or harmful bacteria in drinking water represents significant risks to human health. This study aimed to develop a low-cost water treatment technology using synthesized nanocomposites with metal nanoparticles supported on activated carbon (AC) for bacteria and heavy metal removal. In addition, the performance of the developed nanomaterials was compared with that of commercial materials – carbon fibers of three different typologies. The chemical and textural properties of all tested materials were characterized. To simulate a technology to be applied in a water outlet point, removal tests were carried out in a continuous system using suspensions of Escherichia coli and/or Staphylococcus aureus, wherein the contact time with the two phases was minimal (1 min). The obtained results revealed that iron and copper oxides supported on AC with a calcination treatment (CuFeO/AC-C) was the nanocomposite with the best performance, achieving a 6 log reduction for both bacteria in the same suspension up to 9 h operation. A mix of bacteria and heavy metals, simulating a real water, was treated with CuFeO/AC-C obtaining a 6 log reduction of bacteria, a Pb2+ removal >99.9% and Cd2+ removal between 97 and 98% over 180 passage times. [ABSTRACT FROM AUTHOR]

Heavy metals pollution damages coastal swamp ecosystems. This study's primary purpose was to determine the amounts of heavy metals in coastal swamp waters and the tissues of three fish species (Mugil cephalus, Arius sagor and Plotosus lineatus). This study determined that the water in the coastal swamps of South Kalimantan was contaminated with heavy metals in the following order: Fe > Cu > Zn > Cr > Pb > Cd > Hg. The heavy metal concentrations found in the three commercial fish species are as follows: Fe > Zn > Cu > Cr > Pb > Cd > Hg. The bioaccumulation of heavy metals was highest in Mugil cephalus, followed by Arius sagor and Plotosus lineatus. The Fe, Cu and Cr concentrations in Mugil cephalus, Arius sagor and Plotosus lineatus exceeded the international and national MPLs. The liver tissue has the highest capacity to bioaccumulate heavy metals. Regular monitoring of these metals in fish and water sources is recommended to ensure the safety and conservation of coastal swamp wetlands. [ABSTRACT FROM AUTHOR]

Marine fish tend to accumulate heavy metals (HM) in various body parts, which biomagnifies in the food chain. Consumption of fish with elevated HM levels by fish-eating population, is likely to express HM toxicity disorders in human beings. Therefore, it is imperative to study HM concentrations in marine waters and in various parts of fishes from the landing areas. In the present study, HM concentrations in marine waters and various organs of selected indicator fish and shrimp species from the four landing centers of Ratnagiri district, Maharashtra are studied in comparison with the standards given by various global agencies. The indicator species of fish and shrimps selected in this study can only throw light on the concerns about the possibility of HM toxicity to the population. The indicator species are selected from inshore waters as it is the breeding ground for these species which receives run-off from industrial waste, agricultural operations and other anthropogenic activities such as tourism as well as from the maintenance of the many fishing vessels, hence highly polluted as compared to offshore water. HM concentrations in water and fish organs are estimated using AAS. Four non-essential HM viz. Pb, Cd, Ni and Cr are studied. Ni and Cr are found to be 'below detectable level (BDL)' in the water samples of all the four landing zones. Cd is reported to be below detectable level at Mirkarwada, whereas Pb is found to be higher at Mirkarwada and Dabhol. For all other centers both Cd and Pb have shown total HM accumulation in various body parts well within the limits, outlined by various global agencies. The study also reveals that the HM accumulation is found to be lowest in fish tissue, which is the only edible part. [ABSTRACT FROM AUTHOR]

The ecological integrity of several freshwater ecosystems has been disrupted by the rapid and unrestrained accumulation of toxic heavy metals (HMs) from various sources. Changes in land use and land cover, in the form of urbanization and industrialization, have significantly affected the surface-water quality of freshwater ecosystems by causing an upsurge in pollutant loads. In addition, agricultural runoff has contributed to the decrease in water quality. Almost 70% of India's surface-water resources have become polluted owing to the discharge of untreated sewage and industrial effluents, according to a recent report by the Central Water Commission (CWC) of India, with 42 rivers containing at least two HMs in concentrations above the permissible limit. The aquatic biota inhabiting contaminated sites can accumulate HMs from the surface water. In high concentrations, these HMs can damage biotic components, predominantly by triggering oxidative stress and becoming bioaccumulated in different trophic levels of freshwater ecosystems. Heavy metal contamination in the aquatic environment can also cause direct potential hazards to humans, mostly through their consumption of fish and waterfowl. Thus, it is recommended that the untreated wastewater discharge from industry, agricultural fields, and households be curtail to improve surface-water quality. In this systematic review, we investigated the probable sources of the HMs, the HM contamination in the important rivers and wetlands of India, the effects of HM toxicity on freshwater food chains, and potential remediation measures. The findings of the present study will improve our knowledge about the spectrum of HM toxicity and the effects of HM contamination on the biota in freshwater bodies throughout India, and will also aid policymakers in building strategic and sustainable freshwater management plans around the globe. [ABSTRACT FROM AUTHOR]