High Concentrations Of Heavy Metals Research Articles

Assessment of pollution in Alibeykoy Dam Lake (Istanbul, Türkiye) and its influent streams: Phytoplankton composition and heavy metal accumulation.

In this study, the pollution levels of Alibeykoy Dam Lake were assessed by examining phytoplankton distribution, physicochemical parameters, nutrient content, and heavy metal concentrations. Alibeykoy Dam is a critical drinking water source for the Istanbul metropolitan area. Water samples were collected from the lake and six influent streams (Cebeci, Pirincci, Sidan, Bolluca, Gulgen, and Kocaman) in January, February, May, and September of 2021. A total of 36 taxa from seven divisions were identified, including Bacillariophyta (14), Charophyta (2), Chlorophyta (9), Cryptophyta (1), Cyanobacteria (3), Euglenozoa (4), and Miozoa (3). Diatoms were found to be the dominant group in terms of species richness and abundance. The dominant species recorded in each site were as follows: Microcystis aeruginosa in Alibeykoy Dam and Sidan Creek, Cyclotella ocellata in Cebeci and Gulgen Creeks, Scenedesmus sp. in Pirincci Creek, Navicula cryptocephala in Bolluca Creek, and Sphaerocystis planctonica in Kocaman Creek. Mesotrophic and eutrophic phytoplankton species suggested that the lake is nearing eutrophic conditions. This conclusion was further supported by high concentrations of heavy metals and nutrients detected in the water samples. This research is significant because it provides a comprehensive understanding of the ecological status of Alibeykoy Dam Lake, a critical resource for drinking water in Istanbul. The study highlights potential risks associated with eutrophication and heavy metal accumulation by identifying pollution levels and dominant species. These findings are vital for implementing effective water resource management strategies, ensuring the lake's sustainability, and protecting public health. PRACTITIONER POINTS: The pollution rate of Alibeykoy Dam Lake was determined. The presence of mesotrophic and eutrophic species of phytoplankton indicated the lake's trophic structure. The measurements were done to estimate the lake's heavy metal and nutrient contents.

Combination of lime stone and fly ash in the adsorption of iron (Fe) metal from coal acid mine drainage

Coal mining activities often produce acid mine drainage characterized by low pH values below 5 and high concentrations of heavy metals including iron (Fe). If the water is not managed properly, it can impact the environment due to the influence of acidity and high concentrations of dissolved metals. This research aims to utilize the combination of activated limestone and fly ash by heating at 110°C for 3 hours for acid mine drainage treatment, namely neutralizing pH and adsorbing heavy metal Fe. The selection of adsorbent materials was based on economic considerations, abundant availability, and utilization of fly ash waste. The method used was batch adsorption experiments with contact times of 30 and 60 minutes. Acid mine drainage from coal mine with initial pH 4.55 and Fe metal concentration 7.58 mg/L. The adsorbent combination of limestone and fly ash in the ratio of 1:1, 1:2, and 2:1. From the experimental results, it was obtained that the adsorbent combination was able to neutralize pH up to 6 and remove Fe up to 1.35 mg/L was the ratio of 1:2 with a stirring time of 30 minutes. So it can be concluded that adding fly ash dose 2 times compared to the dose of limestone is more effective to raise the pH value and remove Fe heavy metal, because the higher the dose given, the more ion adsorption sites will be available

ECOLOGICAL AND ECONOMIC ASSESSMENT OF THE STATE OF FOREST ECOSYSTEMS IN THE CONDITIONS OF MARITAL STATE IN UKRAINE

The purpose of the article to investigate the current ecological state of forest ecosystems on the example of the Vinnytsia Forestry branch of the State Enterprise Forests of Ukraine under the conditions of martial law in Ukraine. Methods. The methodological basis of this research is: empirical (field experiments and observations; measurement of indicators of the research object; theoretical (putting forward a hypothesis and forming conclusions based on research results; statistical; mathematical. Results. In the territory of the forest ecosystems of the Hnivan Forestry at the point of soil sampling at a distance of 1000 m from the point of explosion of the fragment, there were no exceedances of the MPC, although the concentration was close to the MPC. Thus, the concentration of Pb, Cd, Zn, and Cu was lower than the MPC by 1.03, 1.07, 1.18, and 1.86 times, respectively. The highest content of heavy metals in point №2 was Cu, and it was higher than Pb, Cd, and Zn by 5.06, 45.33, and 1.51 times, respectively. The highest content of heavy metals in Voronovetski forestry at the point of explosion was Cu, compared with Pb, Cd, and Zn in 3.03, 23.23, and 1.94 times, respectively. In soil sample №2, no exceedance of the MPC of heavy metals was observed, the total content of Pb, Cd, Zn, and Cu was lower than the MPC by 1.31, 1.48, 1.4 and 2.6 times, respectively. At that time, the highest content of heavy metals in sample №2 was Cu, which was higher compared to Pb, Cd, and Zn by 4.61, 44.9 and 1.29 times, respectively. The hazard ratio in sample №1 of Hnivan forestry was higher for Pb, Cd, Zn Cu by 4.27, 2.69, 1.46, and 2.03 times, respectively, compared to sample №2. Similarly, when comparing the indicators of the hazard ratio between the samples taken on the territory of the Voronovytskyi forestry, the hazard ratio in sample №1 was higher for Pb, Cd, Zn, and Cu by 4.14, 5.22, 1.8, and 2.73 times, respectively, compared to sample №2. Conclusions. The content of heavy metals in the soils of the SE "Vinnytsia Forestry" on the territory of the Hnivansky and Voronovytskyi forests exceeded the maximum permissible concentrations in the samples taken on the territory of forest ecosystems at the explosion points of fragments of downed missiles. The content of Pb, Cd, Zn and Cu was higher than the MPC by 4.11, 2.48, 1.23 and 1.08 times, respectively, in samples from Hnivan Forestry. In the territory of forest ecosystems of the Voronovytskyi Forestry the concentration of Pb, Cd, Zn, and Cu was higher than the MPC in 3.15, 3.52, 1.28 and 1.04 times respectively. The studied indicators of the hazard ratio exceed the numerical value of 1 in the selected samples in the zone of the rupture of the missile fragment, both in the territory of Hnivanskyi and in the territory of Voronovetski forestry, which indicates that this territory is dangerous for harvesting non-wood forestry products and breeding of forest species.

Potential risk of heavy metals release in sediments and soils of the Yellow River Basin (Henan section): A perspective on bioavailability and bioaccessibility.

The ecology of watersheds plays an important role in regulating regional climate and human activities. The sediment-soil system in the middle and lower reaches of the Yellow River Basin (Henan section) was explored. The spatial distribution characteristics of heavy metals (HMs) showed that tributaries, which are affected by anthropogenic activities, contain higher concentrations of HMs than the main channel. Sequential extraction experiments indicated that Cd had the strongest potential to be released, followed by Mn. In vitro simulation experiments showed that gastric and pulmonary fluids rendered these two orders of magnitude more bioaccessible compared to sweat. Moreover, Cd exhibited the highest bioaccessibility in both gastric and lung fluids. When bioaccessibility was considered in the evaluation of health risks, more than 82 % of reductions in non-carcinogenic and carcinogenic risk indices were observed in children and adults. A positive matrix factorization model was utilized to determine the potential sources of HMs: industrial sources, natural sources, and mixed agricultural and transportation sources were identified as the three main sources of HMs in sediments and soils. In addition, mining activities were also an HMs source in sediments.

Distribution and Source-specific Ecological Risk Analysis of Soil Heavy Metals in South Hunan Province

To identify the spatial distribution patterns and assess the ecological risks associated with soil heavy metal pollution in the southern region of Hunan Province, a total of 362 surface soil samples were collected from the studied area. This study employed multivariate statistics and geographic information systems （GIS） to investigate the spatial distribution pattern of soil metals （Cd, Hg, As, Pb, Zn, Ni, Mn, Tl, and Sb）. Furthermore, the pollution sources and source-specific ecological risk of heavy metals were quantified by combining the positive matrix factorization （PMF） model and the comprehensive ecological risk index model. The results suggested that the mean concentration of soil metals in the study area exceeded the mean background values. Specifically, Cd, Hg, Pb, and Sb showed significant pollution levels and substantial spatial variability, with their concentrations reaching the background values by factors of 8.31, 9.12, 5.09, and 2.79, respectively. The spatial distribution of these heavy metals exhibited discernible patterns, with a higher concentration observed in western Chenzhou and a noticeable trend of increasing concentrations from the central region towards the periphery. The clusters with high concentrations of heavy metals were predominantly situated near industrial zones engaged in black metal smelting and processing and nonferrous metal mining and processing enterprises. Source apportionment indicated that the primary sources of soil heavy metals in the area were industrial activities associated with black metal mining and metallurgy （29.06%）, atmospheric deposition （22.05%）, nonferrous metal mining and processing （20.65%）, a combination of industrial and transportation sources （14.73%）, and natural sources （13.50%）. Moreover, the source-ecological risk assessment model specifically identified Cd and Hg as crucial elements requiring prioritized control measures to mitigate soil ecological risks. Industrial activities, including black metal smelting and processing and atmospheric deposition sources, were identified as the priority sources for health risks in the study region. These results provide an important theoretical basis for the development of effective strategies aimed at managing and diminishing the risks associated with heavy metal contamination in the southern region of Hunan Province.

Root-associated functional microbiome endemism facilitates heavy metal resilience and nutrient poor adaptation in native plants under serpentine driven edaphic challenges.

Serpentine soils are characterized by high concentrations of heavy metals (HMs) and limited essential nutrients with remarkable endemic plant diversity, yet the mechanisms enabling plant adaptation to thrive in such harsh environments remain largely unknown. Full-length 16S rRNA amplicon sequencing, coupled with physiological and functional assays, was used to explore root-associated bacterial community composition and their metabolic and ecological functions. The results revealed that serpentine plant species exhibited significantly higher metal transfer factor values compared to non-serpentine plant species, particularly evident in Bidens pilosa, Miscanthus floridulus, and Leucaena leucocephala. The serpentine root-associated microbes showed a higher utilization of carboxylic acid, whereas carbohydrate utilization was higher in the non-serpentine site. Zymomonas mobilis and Flavabacterium sp. exhibited high resistance to heavy metal concentrations, showing greater adaptability, while, Staphylococcus carnosus showed sensitivity to HMs, showing limited adaptability. Moreover, Ni, Cr, and Co resistance genes were found, while nitrogen and phosphorous metabolism genes were less abundant in the serpentine site compared to the non-serpentine site. Furthermore, Flavobacterium sp. had a strong positive relationship with Cd and Cu, Zymomonas mobilis with Ni, and Cr, Streptomyces sp. with Co, and Staphylococcus carnosus with N and P cycling. These findings underscore critical role of root-associated bacterial communities and distinctive soil conditions of serpentine habitats in fostering ecological adaptation of native plant species to the challenges posed by HMs and nutrient deficiencies.

Relationship between soil fertility in foothills and inorganic components

In newly formed soils with low humus content, high concentrations of heavy metals do not have a positive effect on the development of green vegetation. In soils contaminated with crude oil, oil refining waste and heavy metals, green vegetation is not observed regardless of the concentration of heavy metals. However, in soils rich in humus and free from oil industry waste, restored or unpolluted by oil refining emissions, the development of green vegetation is directly proportional to the concentration of metals, including heavy metals. Fertile soils of mountainous and foothill areas are characterized by relatively high concentrations of mineral components and natural radionuclides. These results are in good agreement with the higher degree of development of herbaceous vegetation, green shrubs and trees observed in foothill areas, which is explained by both high soil fertility and the participation of microelements and natural radionuclides in accelerating photosynthesis processes.

Unlocking Biochar's Potential: Innovative Strategies for Sustainable Remediation of Heavy Metal Stress in Tobacco Plants.

Tobacco, being a globally cultivated crop, holds significant social and economic importance. Tobacco plants are susceptible to the adverse effects of heavy metals (HMs), particularly cadmium (Cd), which hinders root development, disrupts water balance, and impedes nutrient absorption. Higher concentrations of HMs, especially Cd, naturally accumulate in tobacco leaves due to complex interactions within the plant-soil continuum. The uptake of Cd by plants from the soil is influenced by several factors, including soil type, pH, irrigation water quality, and the chemical composition of the metal involved. Different techniques, such as bioremediation, phytoremediation, and mycoremediation, have been employed to tackle the issue of HMs. The use of biochar offers a practical solution to mitigate this problem. With its large surface area and porous nature, biochar can effectively alleviate HMs contamination. Under biochar application, metal adsorption primarily occurs through physical adsorption, where metal ions are trapped within the pores of the biochar. Additionally, electrostatic attraction, in which negatively charged biochar surfaces attract positively charged metal ions, is another major mechanism of metal remediation facilitated by biochar. In this review, we documented, compiled, and interpreted novel and recent information on HMs stress on tobacco plants and explored biochar's role in alleviating HMs toxicity. By providing a comprehensive review of the persistent threat posed by Cd to tobacco crops and exploring biochar's potential as a remediation measure, this work aims to enhance our understanding of HMs stress in tobacco and contribute to the development of sustainable agricultural practices.

Environmental Risk Assessment of Heavy Metals in Dust and Their Impact on Roadside Plants Due to Traffic Activity in Diyala Governorate, Iraq.

ABSTRACT: The current study aims to evaluate the levels of dust pollution on plants grown on roadsides and resulting from traffic in Diyala Governorate. Four locations were chosen that represent different levels of traffic density and industrial activity: Al-Tabu Street, Khuraisan Street, Buhriz Street, and Hay Al-Muallem Street. Concentrations of heavy metals were measured, including lead [Pb], cadmium [Cd], copper [Cu], and zinc [Zn], and the results showed The highest concentration of heavy metals was recorded in zinc, which reached 145.9 mg/kg and lead, 61.2 mg/kg. This is attributed to Due to the high traffic density and industrial activities, the lowest concentrations were in Buhriz Street, where the lowest concentration of cadmium was 1.2 mg/kg, while the copper concentration reached 22.1 mg/kg due to the lack of traffic activity. The current study also included measuring the physiological functions of plants, including [ Photosynthesis rate, stomatal measurement, and chlorophyll concentrations], as the results showed that dust accumulation has effects on the physiological functions of plants, through a decrease in construction efficiency. Photosynthesis and differences in chlorophyll concentrations. The study also showed the impact of traffic and industrial activities on plant life as a result of dust falling on the surfaces of their leaves, which emphasizes the importance of working to reduce dust pollution levels in urban areas to improve environmental quality.

Heavy Metal Spatial Variation Mechanism and Ecological Health Risk Assessment in Volcanic Island Soils: A Case Study of Weizhou Island, China

Heavy metals in volcanic island soils are key for assessing pollution risks and guiding environmental management strategies. However, research on heavy metals in volcanic island soils remains limited. In this study, the concentrations of heavy metals (Cu, Zn, Pb, Cr) in surface soil samples from Weizhou Island, China, were determined using ICP-OES, with average concentrations of 59.18 mg/kg, 119.06 mg/kg, 35.63 mg/kg, and 159.78 mg/kg, respectively. The basalt profiles generally exhibit higher heavy metal content and pH values compared to volcaniclastic rock profiles, as basalt accumulates higher concentrations of heavy metals. However, surface soils over volcaniclastic rocks show significantly higher heavy metal concentrations than those over basalt, indicating spatial variability in metal accumulation. Heavy metal concentrations in Weizhou Island soils are notably elevated at both the western wharf and the island’s tail, both characterized by volcaniclastic rock lithology, with human activities further increasing concentrations at the western wharf compared to the island’s tail. Land use types influence heavy metal content, with higher concentrations in abandoned land and lower concentrations in forest land with dense vegetation and organic matter. Principal component analysis reveals that heavy metals are primarily derived from natural parent material, with the first two principal components comprising 59.77% of the variance. Ecological risk assessment indicates that Weizhou Island soil is generally considered relatively clean, but Pb presents an ecological hazard, with 86.54% of the sites at risk. Overall, heavy metals in volcanic island soil mainly come from natural sources but lead contamination and human-impacted areas require attention.

Study on the Adsorption Performance of Lead Ions in Water by Phosphate Base Polymer with Different Ratio

Red mud, a by-product of the aluminum industry, poses a threat to the environment with its high alkalinity and heavy metal content and may seep into the soil and groundwater, endangering ecology and health. Effective utilization of red mud can reduce pollution and achieve resource recycling. In this study, a metakaolin/red mud geopolymer was prepared by phosphoric acid excitation to investigate its adsorption capacity for lead ions. The ratio of metakaolin to red mud and the additions of phosphoric acid and water were optimized, and the optimal formulations were 3/7 mass ratio of metakaolin to red mud, 2.2 molar ratio of H3PO4/Al2O3, and 0.5 water-solid ratio, which demonstrated good stability and operability.

Research progress on acid mine drainage treatment based on CiteSpace analysis

Acid mine drainage has always been of global concern, primarily due to its low pH, high concentration of heavy metals and toxic substances, and serious impact on the surrounding environment and ecology of mines. However, the research progress and hotspots in this field of acid mine drainage processing are still unclear. To better understand the research hotspots and trends of acid mine drainage processing from 2004 to 2023, we used CiteSpace bibliometric software to visually analyze 1142 English-language research articles and reviews from the Web of Science core database. Results indicated that this field has received increas-ing attention from researchers worldwide, especially since 2017. The USA and China stand out as major contributors, yet their international collaboration doesn't match South Africa robust partnerships. Strengthening cooperation with other nations should be a priority for both the USA and China. The University of Quebec and University of South Africa were the most production institution. Vhahangwele Masindi from South Africa was the most active author. The top two core journals in this field were Science of the Total Environment and Water Re-search. Additionally, through keyword co-occurrence, clustering, and burst analysis, it is evi-dent that research on heavy metal mechanisms and resource recovery will be the future re-search hotspots in this field of acid mine drainage. This study provides researchers with an opportunity to understand the hotspots and trends in acid mine drainage research from a bibliometric perspective, and serves as a reference for future studies.

Determination of Heavy Metals and Hemato-Biochemical Profiling of Bagre marinus and Bagarius bagarius in Jhelum River

Heavy metals enter river basins through industrial effluents, agricultural wastes, surface run-offs, and other human activities, negatively impacting aquatic and terrestrial life by bioaccumulating in the food chain. This problem is on a continuous rise in under-developed and developing countries, such as in Pakistan. Therefore, the current study was aimed to determine concentrations of heavy metals, essential trace elements, and macrominerals (Zn, Pb, Ni, Mn, Mg, Fe, Cu, Cr, Co, Cd, Ca, and As) in the water, sediments, and tissues (gills, liver, and muscles) of Bagarius bagarius and Bagre marinus in the Jhelum River, Pakistan. The hematological and biochemical profiles of these fish across two sampling sites (Jhelum Bridge Khushab, upstream, and Langarwala Pull—downstream) were also evaluated. Results showed greater bioaccumulation of heavy metals in fish downstream, correlating with higher concentrations of these metals in water and sediments downstream. In the case of B. marinus, the highest concentration observed was 16.59 mg/g (Ca), and the lowest concentration was 9.51 mg/g (Fe). In the case of B. bagarius, the highest concentration observed was 17.47 mg/g (Ca), and the lowest concentration was 7.95 mg/g (Mg). Increased activities of alkaline phosphatase (ALP), alanine aminotransferase (ALT), aspartate aminotransferase (AST), and lactate dehydrogenase (LDH) were observed downstream. Hematological changes included increased white blood cells (WBCs) and decreased red blood cells (RBCs), lymphocytes, hemoglobin (Hb), platelets (Plt), and hematocrit (Hct). A significant correlation was observed among heavy metals across the water, sediment, and different tissues of B. marinus and B. bagarius. Moreover, principal component analysis (PCA) for both species along both sampling sites illustrated the relationship between fish tissues and metals. The current study concluded that the fish accumulated a significantly higher concentration of heavy metals downstream, which might be linked with dumping of the domestic wastes and industrial and agricultural runoff, adversely affecting both fish and human health.

Exploration and impact of Metlaoui-Gafsa phosphate rock amendment: the role of Serratia plymuthica BMA1 in phosphate solubilization, heavy metal rhizoaccumulation, and enhanced nutrition in Vicia faba L.

The geochemical analysis of Gafsa rock phosphate (GRP) revealed relatively high concentrations of essential plant minerals and trace heavy metals (HMs). Environmental contamination factors indicated moderate to very strong HM contamination due to GRP soil amendment. The potential use of the Serratia plymuthica BMA1 strain, which is known for its ability to solubilize GRP, to enhance mineral nutrition in Vicia faba L. and its role in HM rhizoaccumulation from GRP were explored. Pot experiments revealed that bacterization with S. plymuthica BMA1 in V. faba grown in sand supplemented with GRP as the sole source of phosphorus significantly increased the potassium concentration by 64% in roots and 40% in shoots, iron by 20% in roots and 10% in shoots, and manganese by 27% in roots and 20% in shoots compared to that in V. faba not inoculated with S. plymuthica BMA1. The total dry biomass of V. faba increased by approximately 85%, while the accumulation of cadmium (Cd), copper (Cu), zinc (Zn), and lead (Pb) in the roots increased by 114%, 30%, 37%, and 44%, respectively. However, in the shoots, they increased by 35%, 10%, 85%, and 25%, respectively, for Cd, Cu, Zn, and Pb compared to those in the non-inoculated V. faba. The evaluation of the HM translocation factor, bioaccumulation factor, and bioconcentration factor with GRP highlighted the key role of S. plymuthica BMA1 in preventing the mobility of toxic HMs from reaching the aerial parts of plants. These findings suggest that S. plymuthica BMA1 has the potential to enhance mineral nutrition in V. faba and facilitate the rhizoaccumulation of toxic HMs, which has implications for plant cultivation and human consumption.

Health Risk Assessment of Heavy Metals in Soil-crop System in Different Ecological Regions of Ningxia

Heavy metals are characterized by toxicity，non-biodegradability，and accumulation in the food chain；hence，o the distribution of heavy metals in farmland soils and crop food safety have attracted much attention. A total of 1 274 soil samples and crop samples were collected from farmland in Ningxia from 2017 to 2021 and bioconcentration coefficients were used based on the analysis of the elemental contents of Zn，Cr，Ni，Cu，Pb，As，Cd，and Hg. The ecological risk index and correlation analysis were used to characterize the heavy metal content and health risk assessment of the soil-crop system in Ningxia. The results showed that the soils in the study area were alkaline and the mechanical composition was dominated by pulverized and sandy grains，with a relatively small content of clay grains. The heavy metal contents in the soils were in the following order：Zn>Cr>Ni>Cu>Pb>As>Cd> Hg. Except for that of Cu and Ni，the contents of other heavy metals in the soils of the northern region were higher than those of the central and southern regions. The ecological risk index of soil heavy metals was Hg>Cd>As>Cu>Pb>Ni>Cr>Zn and the proportion of points with low and medium ecological risk index levels was high（98.58%），indicating that the soil environment was generally good. The average content of the eight heavy metals in crops did not exceed the limit value，and the average health risk index value was <1. However， the health risk index（HRI）of As in individual crops existed at points >1 in all three sub-regions and individual points with high values of HRI（HRI>1）for Cu and Ni were observed in crops in the northern region and for Pb in the north and south of the country，which require further attention. From the bioconcentration factor，crops showed no accumulation effect （BCF<1）for heavy metals such as As，Cd，Cr，Cu，Ni，Pb，and Zn and although the average uptake of Hg by crops did not show accumulation，a total of 31 crops in the three ecological zones showed some accumulation（BCF>1），which also requires further monitoring. Analysis using the Mantel's test showed that except for As and Ni in crops，which had a weak correlation with Cu content in the soil（0.05>Mantel's P>0.01），the other heavy metals in crops did not have a significant correlation with the corresponding soil heavy metals （Mantel's P≥0.05），indicating that the heavy metal contents in crops were less affected by soil heavy metals. RDA analysis showed that the sand content had a strong positive correlation with the transfer coefficients of heavy metals such as Hg，Ni，Pb，and Cd，while the powder content showed a strong negative correlation；however，the transfer coefficients of Cu，Zn，As，and Cr were not much affected by the mechanical composition of soils，and the correlation between the soil organic matter content and the transfer coefficients of heavy metals was also small. In summary，the quality of the soil environment and crops in the study area is generally good；however，attention must still be paid to the areas with high heavy metal content or exceeding the standard value to strictly control the input of pollutants，and at the same time，establishing long-term monitoring of the quality status of soil and agricultural products in the crop production area is a necessary control initiative.

Trace Elements Spatial Distribution in the Groundwater near the Subarnarekha River Basin - Jamshedpur, India

The present study assessed the spatial distribution of trace elements in the groundwater near the Subarnarekha River Basin - Jamshedpur, India. Half of this city's water need (48.11%) relies on groundwater resources. GIS-based maps were constructed using ArcGIS 10.3 software to describe the spatial distribution of Arsenic (As), Barium (Ba), Cadmium (Cd), Chromium (Cr), Cobalt (Co), Copper (Cu), Iron (Fe), Manganese (Mn), Molybdenum (Mo), Nickel (Ni), Selenium (Se), and Strontium (Sr). The concentration of trace elements was investigated in the groundwater sample of 30 wells by the Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). Many samples contained levels of Sr (100 µg/L), Cu (50 µg/L), Co (10 µg/L), and Mn (300 µg/L) that vastly exceeded the limits of the Bureau of Indian Standards (BIS) limit, which may directly affect the human health. The northern region of the study area exhibits higher concentrations of heavy metals. The groundwater table was monitored using a sensor-based water level recorder during pre and post-monsoon seasons. A significant fluctuation of 4.9 meters below ground level (mbgl) was observed, indicating potential water scarcity in the summer. The findings of this study offer valuable insights into various sources of contamination affecting groundwater in river basins within industrial regions.

Morphological and physiological responses of Momordica charantia to heavy metals and nutrient toxicity in contaminated water

This study investigates the impact of industrial wastewater from leather, household, and marble sources on the growth, physiological traits, and biochemical responses of Momordica charantia (bitter melon). Industrial activities often lead to the release of contaminated effluents, which can significantly affect plant health and agricultural productivity. Water analysis revealed that leather effluent contained high concentrations of heavy metals, including cadmium (2.67 mg/L), lead (1.95 mg/L), and nickel (1.02 mg/L), all of which exceeded the recommended safety limits for irrigation. Seed germination was significantly reduced, with only 45% germination in seeds irrigated with leather effluent, compared to 90% in the control group. Similarly, in plants treated with leather wastewater, shoot length, and root length were reduced by 38% and 42%. Chlorophyll content showed a marked decline, with chlorophyll “a” reduced by 25% and chlorophyll “b” by 30% in wastewater-treated plants, indicating impaired photosynthetic activity. Antioxidant enzyme activity, including catalase and superoxide dismutase, increased by up to 40%, reflecting a stress response to heavy metal toxicity. These findings highlight that industrial wastewater severely disrupts plant metabolic processes, leading to stunted growth and physiological stress. To safeguard crop productivity and food security, stringent wastewater treatment protocols must be implemented to mitigate environmental contamination. Future research should focus on developing advanced remediation techniques and sustainable wastewater management practices to reduce heavy metal toxicity and enhance soil health.

Spatial distributions, potential sources, and ecological risks of heavy metals in stream sediments in Zambia

The ecological risk assessment and source identification of heavy metals (HMs) are significant for resource utilization and food security. This study aims to assess the spatial distributions, potential sources, and ecological risks of HMs in stream sediments in Zambia. Using 735 samples collected from stream sediments across the country and methods such as inductively coupled plasma mass spectrometry (ICP-MS), atomic fluorescence spectrometry (AFS), and X-ray fluorescence spectrometry (XRFS), this study determined the concentrations of the seven HMs, i.e., arsenic (As), chromium (Cr), copper (Cu), mercury (Hg), nickel (Ni), lead (Pb), and zinc (Zn). The spatial distributions of these HMs were determined using a Geographic Information System (GIS), and their ecological risks were accessed based on the analytical results of their potential sources. Additionally, this study explored the relationships between mining activities and regions with high heavy metal (HM) concentrations based on the statistical analysis of the HM concentrations and geology of the study area. The results indicate the stream sediments in Zambia exhibit average As, Cr, Cu, Hg, Ni, Pb, and Zn concentrations of 1.49 × 10−6, 19.34 × 10−6, 12.12 × 10−6, 12.70 × 10−9, 7.13 × 10−6, 12.52 × 10−6, and 16.30 × 10−6, respectively. The analytical results of the geoaccumulation index (Igeo) and potential ecological risk index (PERI) reveal the presence of relatively high As and Cu concentrations, especially in Copperbelt and North-Western provinces and areas surrounding Lusaka—the capital of Zambia. The HM contamination in stream sediments in Zambia is primarily caused by Cu and gold (Au) mining. This study exemplifies how to determine potential sources and ecological risks of HMs in stream sediments, holding important implications for nation-scale environmental contamination prevention and land utilization planning.

Molecular disruptions in microalgae caused by Acidithiobacillus ferrooxidans: Photosynthesis, oxidative stress, and energy metabolism in acid mine drainage.

Microalgae are recognized for their potential in the bioremediation of acid mine drainage (AMD), despite the challenges posed by AMD's low pH, high heavy metal content, and oligotrophic conditions. However, the impact of AMD chemoautotrophic microorganisms on microalgal growth and remediation efforts within AMD has been largely overlooked. This study aims to elucidate the effects the chemoautotrophic microorganism, Acidithiobacillus ferrooxidans, on the growth activity and metabolism of acid-tolerant microalgae, and to explore the molecular mechanisms of microalgal response. Our findings reveal that the presence of A. ferrooxidans inhibits the growth and alkaline production of Parachlorella sp. MP1, resulting in a 90.86 % reduction in biomass. Physiological, biochemical, and transcriptomic studies, indicate that oxidative stress, photosynthesis, and energy metabolism are the metabolic processes most affected by A. ferrooxidans. Specifically, A. ferrooxidans introduces an increased production of reactive oxygen species (ROS) in Parachlorella sp. MP1, leading to an upregulation of genes and enzymes associated with peroxisome activity and intensifying oxidative stress within the cells. Downregulation of photosynthesis-related genes disrupts the electron transport chain, inhibiting photosynthesis. Furthermore, alterations in the gene expression of pyruvate and acetyl-CoA metabolic pathways result in energetic pathway disruption. These insights contribute to a better understanding of how A. ferrooxidans influence the growth metabolism of acid-tolerant microalgae in AMD environments and inform the optimization of microalgal application strategies in AMD bioremediation engineering.

Analysis of Heavy Metal Content of Mn, Cu, Fe, Zn, Pb in Agricultural Irrigation Water and Soil After Tin Mining

Abstract The content of heavy metals Mn, Cu, Fe, Zn, and Pb in agricultural irrigation water and precast tin mining soil revealed that heavy metal concentration levels had exceeded the safe limit according to health standards. The concentration of these heavy metal coils affects plant growth and the quality of agricultural products. Analysis methods used include atomic absorption spectrophotometer and flame emission spectrometry. Data collection from various literature sources that discussed the content of heavy metals in the former tin mine area. The study revealed Mn, Cu, Fe, and Zn in water and agricultural rice field soil according to the quality standard, and the Pb level in irrigated water and soil was quite high, more than 0.1 mg/L, exceeding the limit set by the quality standard. High heavy metal concentrations in post-tin mining areas can endanger human health and the environment. Comprehensive recovery efforts are needed to reduce the content of heavy metals in post-tin mining farmland so that water and soil quality can be improved.