Analysis Of Heavy Metals Research Articles

Spatial Distribution, Pollution Assessment, and Source Analysis of Soil Heavy Metals Under Different Land Use Types in the Southern Area of Laizhou Bay

To ascertain the status of the surface soil heavy metal pollution in the southern area of Laizhou Bay, 263 surface soil samples were collected from seven different land use types in the study area and the contents and pH of eight soil heavy metals （As, Cr, Ni, Cu, Zn, Cd, Pb, and Hg） were determined. The pollution assessment was carried out using the geo-accumulation index method, Nemerow comprehensive index method, and potential ecological risk index method. Then, the source of heavy metal pollution was discussed using correlation analysis and the source analysis was carried out through positive matrix factorization （PMF）. The results showed that the surface soil in the study area was weakly alkaline； As, Ni, Zn, and Hg slightly exceeded the background values of Weifang and the spatial distribution of heavy metals showed a trend of low in the north and high in the south. The results of the geo-accumulation index indicated that the study area was pollution free and the geo-accumulation index of different land types was arranged in the order of As>Ni>Zn>Cr>Pb>Hg>Cu>Cd. The results of the Nemerow comprehensive pollution index indicated that the study area was lightly polluted and the Nemerow comprehensive pollution index of different land types was arranged in the order of town>grassland>forest>agricultural land>vegetable land>industrial land>mudflat. The results of the potential ecological risk index indicated that the study area belonged to low ecological risk and the potential ecological risk index of different land types was arranged in the order of agricultural land>town>forest land>grassland>vegetable land>industrial land>mudflat. The results of PMF analysis indicated that the heavy metal pollution sources in the study area mainly included natural sources, transportation sources, agricultural sources, and industrial sources, with contribution rates of 38.06%, 26.38%, 26.21%, and 9.35%, respectively.

Source Apportionment and Influence Factors Analysis of Heavy Metals in Soils Around a Coal Gangue Heap Using the APCS-MLR Model and GeoDetector

To analyze the source apportionment and influence factors of heavy metals in soils surrounding a coal gangue heap in Chongqing, the absolute principal component scores-multiple linear regression （APCS-MLR） model and GeoDetector were used. The results showed that Cd was the primary pollutant and the average values of Cd, Hg, Pb, Cr, Cu, Zn, and Ni were 1.33, 0.29, 32.9, 142, 68.8, 118, and 54.6 mg·kg-1, respectively. Using the APCS-MLR model analysis, mining sources, which were mainly affected by long-term accumulation of the coal gangue heap, had a contribution rate of 37.1% and the main heavy metal pollutants were Cd, Hg, and Pb. Agriculture and transportation sources, mainly affected by pesticide and fertilizer application and vehicle emissions, had a contribution rate of 36.2%, with the main heavy metal pollutants being Cu, Zn, and Ni. Natural sources, which were mainly affected by geotechnical weathering processes of their parent materials, had a contribution rate of 26.7% and the main heavy metal pollutant was Cr. Using GeoDetector analysis, the "distance from coal gangue heap" had the strongest explanatory power for the contents of Cd, Hg, and Pb, whereas the "distance from rural settlements" had the strongest explanatory power for the contents of Cr, Cu, Zn, and Ni. However, the interaction of each influencing factor was enhanced, which indicated that the spatial distribution characteristics of heavy metals were influenced by multiple factors. The combined application of the APCS-MLR model and GeoDetector can make the results of source apportionment and influence factors more comprehensive, accurate, and reliable.

Physico-chemical and heavy metal analysis of ground and surface water obtained from some selected areas in Kaduna metropolis

Water samples from 10 selected boreholes and 3 hand-dug wells within the three areas of Kaduna Metropolis were collected; Physico-Chemical parameters and heavy metals were determined. The results of the Physico-Chemical analysis were obtained in the following range, temperature (17.3-20.9), conductivity (44-60 mV), alkalinity (184-688 mg/l) BOD (6.5-15.4 mg/l) all within the set limit of WHO standard, TDS value (1197-2340 mg/l) fell above the set limit of WHO standard , the chemical constituents were obtained in the following range pH (7.25-7.67), Magnesium (1.28-6.08 mg/l), Calcium (0.12-0.90 mg/l), Nitrate (0.03-0.32 mg/l) with Chloride value (2.33-495.6) above the set limit of WHO standard, the highest value of 0.1241mg/l was found in Chromium. the concentrations of heavy metals (mg/l) Chromium, Iron, Lead, and Copper in the Groundwater were found in the following range, lead (0.0001- 0.120 mg/l), Chromium (0.0001- 0.124 mg/l), iron (0.0191- 0.3547 mg/l) and Copper (0.0006- 0.0070 mg/l). The results obtained fell within the limit set by World Health Organisation with the exception of Chromium which was 0.124 mg/l in sample SH3 and Lead which was in sample MF2. Which these two had concentrations above the limits set by World Health Organisation.

Physicochemical and Heavy Metal Analysis in Industrial Wastewater: Impact on Biodiversity in Morang District, Koshi Province, Nepal

This study investigates the concentration of heavy metal ions in wastewater samples collected from various industrial facilities located in the Biratnagar-Rangeli corridor of Morang district. The physical and chemical parameters, such as pH, electrical conductivity (EC), biological oxygen demand (BOD), and chemical oxygen demand (COD) were measured, and the presence of heavy metals, including iron (Fe), Zinc (Zn), Chromium (Cr), Nickel (Ni), Lead (Pb), and Arsenic (As), was assessed. Atomic Absorption Spectrophotometer (AAS) (Thermo Scientific, ice3000 series, Thermo Fischer, USA) was used to measure heavy metals. The findings reveal elevated levels of these pollutants, particularly Iron (Fe) and Zinc (Zn), which exceed acceptable safety limits. The study also identifies potential impacts on biodiversity, human health, and the local ecosystem, with significant risks associated with long-term exposure.

Monitoring Heavy Metals and Spatial Analysis Using Pollution Indices and Cartographic Visualization: A Case Study in Kosovo

ABSTRACT Environmental challenges in Kosovo are intensified by extensive anthropogenic activities, leading to significant pollution and degradation of natural resources. This study examines inadequate waste management practices, a major contributor to environmental harm, by analyzing heavy metal concentrations – Cu, Cd, Pb, Ni, Cr, Mn, and Fe – in the water and sediment of Lake Henci and the surrounding soils. We used Inductively Coupled Plasma-Optical Emission Spectrometry (ICP OES) for precise metal determination. To quantify pollution levels, we calculated indices such as the Heavy Metal Index (HMI) and the Contamination Factor (CF). This approach allows for a comprehensive evaluation of metal contamination in the region. The findings are illustrated through thematic maps, developed using interpolation techniques within a Geographic Information System (GIS) at a spatial resolution of 10 meters. Furthermore, spatial analyses were conducted to deepen our understanding of contamination patterns and inform regulatory frameworks. The results show slight pollution in the water samples, with some metal concentrations (Cu, Zn, Cd, Pb, and Ni) exceeding EPA and WHO guidelines. In contrast, sediment and soil samples showed heavy metal levels within normal ranges. These findings underscore the necessity for ongoing monitoring and the implementation of comprehensive oversight and regulatory measures to address the environmental challenges in this area.

Comprehensive analysis of heavy metals and antioxidant properties in various spices and propolis

ABSTRACT In this research, various spices, including curry, fenugreek, allspice, ginseng, abaza herb, nutmeg, mahaleb, coriander, cajun spice, propolis, marjoram, star anise, cardamom, poppy, lavender, tarragon, plantago, vitex seed, French lavender, and yarrow were examined for their trace elements and antioxidant contents. Ethanol extractions were used for DPPH, ABTS, reducing power, and total phenolic content tests, revealing that propolis and plantago exhibited the highest antioxidant and phenolic contents, while fenugreek and cardamom showed the lowest. In the heavy metal analysis, samples were dissolved using a microwave, and trace elements were analysed by ICP-OES. Method accuracy was confirmed with NIST-SRM 1515-Apple Leaves certified reference material. Elemental concentrations ranged from 0.013–27 µg/g for Cu, 29–802 µg/g for Fe, 2.13–430 µg/g for Mn, 0.37–5.00 µg/g for Ni, and 3.13–66 µg/g for Zn. These results were compared with existing literature values. This study highlights the balance needed between the beneficial antioxidant properties and potential risks from trace metals in spices and propolis, emphasising the importance of safety in food consumption.

Uncovering the Anthropogenic Influences on Water Quality: A Case of Lake Victoria Shores, Entebbe, Uganda

Lakes serve as vital ecosystems, providing freshwater resources and habitats for diverse species. However, human activities, particularly around lakeshores, have led to significant environmental degradation, including heavy metal contamination. Lake Victoria, the second-largest freshwater lake globally, has been severely impacted by pollution from industrial, agricultural, and urban sources. This research aims at examining the influence of the anthropogenic activities on the water quality of Lake Victoria. Specifically, the study tried to determine the activities undertaken at the Lake shores of Lake Victoria; determined the physico-chemical parameters of the water from the shores and the heavy metal concentration in the water samples obtained from the shores of Lake Victoria. This study utilized a cross-sectional and experimental research designs to assess water quality and anthropogenic influences around Lake Victoria. A total of 150 residents from selected communities were surveyed using a semi-structured questionnaire to gather demographic information, perceptions of water quality and the activities carried out within the shores of Lake Victoria. Water samples were collected from multiple sites along the lake shores for analysis of heavy metals using the Inductively Coupled Plasma Mass Spectrometry (ICP-MS). Water quality parameters were determined In-situ using a multi-parameter water testing kit and Hanna instrument. Results showed that the anthropogenic activities that could have contributed to water degradation include: fishing, transport, agriculture and construction among others. Apart from pH which was outside the permissible limits, all the other water parameters were within the WHO permissible limits. Considering the heavy metal concentration, all the sampled sites apart from one inlet, had the concentrations above the WHO permissible levels an indication of significant heavy metal contamination in the Lake Victoria shores. These findings highlight the urgent need for targeted pollution control measures and regular monitoring to mitigate further environmental degradation. Effective interventions, including stricter regulations and sustainable land use practices within the Victoria shores are essential for safeguarding the lake's ecosystem and the health of surrounding communities.

Assessment and classification of different ashes from waste incinerators in Thailand

Rapid urbanisation and a growing population have led to a huge production of solid waste worldwide. To mitigate solid wastes, Thailand adapts incineration. As a consequence, a variety of fly ashes being produced in large quantities. Fly ash management is therefore a risk for the future. A comparison of the chemical and physical properties of five sources of ashes from the waste incinerators in three regions in Thailand, namely MFA1, MFA2, IFA, and fly ash that used in a ready-mixed concrete plant, CFA1 and CFA2 was conducted. Additionally, bottom ashes, MBA1, MBA2 and IBA were also characterized similarly. The analysis showed that coal fly ash from ready mixed concrete plant of CFA1 and CFA2 were classified under class F and C, respectively. The heavy metal analysis showed that fly ash from MFA1 and IFA has high amount of Zn (7,523 mg/kg and 28,315 mg/kg), followed by MFA1 has high amount of cadmium (127 mg/kg) and MFA1 and IFA showed high concentration of lead (1,955 mg/kg and 1,425 mg/kg). The present study show that fly ash often contains heavy metals, dioxins, and other hazardous substances, highlighting the need for detailed analysis to determine proper handling and disposal methods. Advanced classification systems, which may include parameters such as leaching behavior, particle size distribution, and contaminant concentrations, are essential for categorizing fly ash into appropriate management pathways, such as landfilling, resource recovery, or reuse in construction materials.

Integrated Application of Innovative Technologies for Oil Spill Remediation in Gran Tarajal Harbor: A Scientific Approach

This study examines recovery efforts at Gran Tarajal Harbor following a significant oil spill, employing a combination of innovative technologies tailored to enhance oil spill remediation. Cleanup operations incorporated advanced absorbent sponges with high reusability, absorbent granulates for targeted hydrocarbon capture, bioremediation techniques using allochthonous microorganisms to accelerate natural degradation processes, and the integration of newly designed oil containment barriers coupled with sponges. These technologies were instrumental in effectively mitigating environmental damage, as evidenced by a reduction in hydrocarbon concentrations in sediments from nearly 60,000 mg/kg to under 1600 mg/kg within seven months. Notably, advanced absorbent sponges demonstrated superior capacity for repeated use, optimizing the cleanup process and contributing to the sustainability of the response efforts. The most important finding of this research is the demonstrated efficacy of integrated approach in not only reducing hydrocarbon contamination but also in promoting ecological recovery. Heavy metal analyses revealed that lead and copper concentrations were primarily associated with routine port activities, while mercury levels, attributed to the spill, decreased significantly over time. Tissue analysis of local organisms showed minimal contamination, and assessments of biological communities indicated signs of ecological recovery. This work highlights the necessity of introduce new disruptive technologies in contingency plans.

Characterizing groundwater contamination flow-paths and heavy metal mobilization near a waste site in Southwestern Nigeria

This study investigates potential groundwater contamination near a waste disposal site in southwestern Nigeria. The area's complex geological setting, characterized by fractured rock formations, posed significant challenges for traditional monitoring methods. To address these challenges and comprehensively assess groundwater conditions, we employed a combined approach utilizing Electrical Resistivity Tomography (ERT), Ground Penetrating Radar (GPR), and geochemical analysis of heavy metals and water conductivity. This approach enabled the investigation of groundwater levels, identification of potential contamination zones, and delineation of contaminant flow paths. GPR identified a shallow zone, termed the “shadow zone,” with conductive residues indicating contaminants with anomalous conductivity ranging from 1 to 1.5 m. An intermittent reflection zone at a depth of 1.5–3.5 m suggested the potential presence of leachate-impacted groundwater. ERT confirmed a shallow resistive layer at depths of 0–2 m, attributed to compacted waste and topsoil, around the abandoned main dumpsite. Below this layer, a zone of low resistivity, decreasing downward through a porous weathered zone, was observed. This corresponded to high water conductivity in well data, ranging from 21 to 147 mS/m (equivalent to 6.80 to 47.62 Ω-m), indicating a high conductive anomaly suspected to be a leachate plume at depths of 2–10 m in a sandy-gravelly weathered zone. Validation against ground truth data confirmed the correlation between radar signatures, geoelectrical imaging, and subsurface lithology. Analysis of well and soil samples revealed concerningly elevated concentrations of cadmium, mercury, lead, arsenic, and cobalt, ranging from 641 to 1175 ppb, exceeding established safety limits for drinking water. Additionally, soil samples showed elevated levels of nickel and chromium, generally ranging from <0 to <1 ppb. These findings highlight the significant risk of groundwater contamination due to the proximity of the leachate zone to the groundwater table in the weathered basement complex. This study demonstrates the effective integration of geophysical and geochemical methods for comprehensive mapping of contaminated zones and identification of preferential pathways for contaminant migration. The findings underscore the critical need for implementing comprehensive risk assessment methodologies in similar complex geological settings.

Measurements of Heavy Elements and Radioactivity Concentration Levels in Types of Fertilizers and Pesticides Commonly Used in Sana’a Yemen

This study aims to measure heavy metals (HMs) concentration and radioactivity concentration levels in fertilizer and pesticide samples collected from local markets in Sana’a, Yemen. Gamma spectroscopy employing a Survey Sodium Iodide NaI (TI) RIIDEYM-G detector was used for radiation and dose assessments. As for heavy metal analyses, this study used Inductively Coupled Optical Emission Spectroscopy (ICP-OES). Thirty samples were collected from local markets in Sana’a, Yemen. Radioactivity measurements show low levels of radioactivity concentration. The average dose rates due to fertilizer and pesticide samples were 1.14 and 1.07 mSv/y, respectively. These values are nearly equal to the recommended annual radiation dose rate limit (1mSv/y) recommended by the International Commission on Radiological Protection (ICRP). For heavy metal analysis, it was found that the average concentrations of heavy metals (HMs) (cadmium (Cd), chromium (Cr), copper (Cu), iron (Fe), nickel (Ni), lead (Pb), and zinc (Zn)) in the fertilizer samples were 1.08 mg/kg, 4.944 mg/kg, 13.8495 mg/kg, 274.371 mg/kg, 3.30446 mg/kg, 15.35686 mg/kg, and 24.4547 mg/kg, respectively. Heavy metal concentrations in fertilizer samples were mainly less than European (EU) guideline limits, with the exception of a few samples. The average concentrations of heavy metals (Cd, Cr, Cu, Fe, Ni, Pb, and Zn) in the pesticide samples were 0.8 mg/kg, 0.5784 mg/kg, 52.280 mg/kg, 73.4651 mg/kg, 2.4482 mg/kg, 3.199 mg/kg, and 1.1309 mg/kg, respectively. The heavy metal concentrations in pesticide samples were less than the corresponding values in fertilizer samples.

Multi-metal resistance and antibiotic susceptibility of biofilm forming bacteria isolated from Kuzhikandam Creek in Kochi, southwest part of India

The purpose of this work was to characterize and identify the bacteria isolated from highly polluted locations that could potentially be able to withstand extremely toxic heavy metals. The study area selected for bacterial isolation from sediment samples was Kuzhikandam Creek, a tributary of the Periyar River and one of the world’s most hazardous hotspots, located in Kochi’s Eloor industrial region. Heavy metal analysis of chromium, copper, and lead in sediment samples was performed, and the results showed that the concentrations were greater than permissible limits. Several metal-resistant bacteria were isolated from sediments, which, upon further screening in solid media at different concentrations of chromium, copper, and lead, found three highly resistant species (S1B1, S2B2, and S3B3), one from each site. The phenotypic and biochemical characterization of these bacteria was examined using standard procedures. The ability of these species to generate biofilm was examined using methods like the crystal violet assay (qualitative assessment) and also using the scanning electron microscope. The antibiotic susceptibility of these species was tested with six different antibiotics, which are used in various disease treatments. These isolates, sequenced using the 16S rRNA Sanger dideoxy method, have been identified as Staphylococcus arlettae, Bacillus paramycoides, and Cellulosimicrobium funkei.

Multivariate Analysis of Water Quality in the Seybouse River: Implications for Pollution Management

ABSTRACTHeavy metal contamination in water bodies is a pervasive and persistent environmental challenge in many parts of the world, especially in developing countries. This study investigates the use of multivariate analysis methods for monitoring variations in water quality along a spatial gradient and for the interpretation of pollution levels at different sampling sites. We assessed the water quality of the Seybouse River and identified possible sources of pollution using three complementary multivariate analysis techniques (PCA, NMDS, and K‐means clustering). The results indicate a longitudinal gradient in water quality associated with industrial and agricultural activities in the middle and lower Seybouse River. Physico‐chemical and heavy metal analyses show high water turbidity with elevated concentrations of iron and chromium. We show that the contamination stems from four different sources, which can be categorized into different pollution levels. Our results suggest that complementary multivariate methods are a robust approach to identifying and categorizing significant sources of pollution in rivers, enabling the development of future successful water quality management strategies based on water pollution levels. This study highlights the importance of monitoring water quality and taking effective measures to control and mitigate pollution from various sources to ensure the safety of the environment and human health.

Exploring Spatial Dynamics of Water Quality in a Tropical Lake Affected by Aquaculture

Lake Maninjau, like many surface water bodies worldwide, faces significant water pollution challenges due to extensive aquaculture activities, making it an ideal site to study the impact of fish farming on water quality, which has contributed to eutrophication and declining water quality. This study investigates the physicochemical parameters and pollution levels in the lake, aiming to provide insights into its environmental health. In August 2022, a comprehensive sampling campaign was undertaken at nine stations within the upper layers of open water and littoral zones of Lake Maninjau. In situ measurements, including temperature, dissolved oxygen, and pH, were conducted, accompanied by water sample collection for laboratory analysis of trace elements and heavy metals. Our study revealed notable variability in water parameters across different sites, with surface water layers exhibiting the greatest differences. While certain parameters such as temperature and conductivity remain relatively stable, pH levels show a decreasing trend with increasing water depth. Dissolved oxygen levels vary widely, while oxidation–reduction potential indicates water pollution, particularly in littoral zones. Potassium dominance within cations likely suggests anthropogenic influences, notably from aquaculture activities, that may also contribute to nutrient enrichment and heavy metal pollution. Elevated levels of total nitrogen and ammonia underscore the lake’s moderate pollution levels, with heavy metals such as mercury exceeding permissible limits, posing risks to aquatic life and human health.

Investigating the role of food pollutants in autismspectrum disorder: a comprehensive analysis of heavy metals, pesticides, and mycotoxins.

Food pollutants, including heavy metals, pesticides, and mycotoxins, have been proposed as potential risk factors for autism spectrum disorder (ASD) during pregnancy and early childhood. This paper examines the impact of food pollutants on ASD risk. A systematic search through PubMed, Google Scholar, and Sciverse yielded studies from 1990 to present. Research indicates elevated levels of heavy metals in children with ASD, linking pesticides and toxins to brain development disruptions. Mycotoxins, specifically, show a correlation with ASD and can contaminate food, posing a threat to neurodevelopment. Strategies like choosing organic foods and reducing exposure to toxins may benefit individuals with ASD and those vulnerable to the disorder. Further research is essential to comprehend the food pollutant-ASD relationship and devise effective exposure reduction strategies.

Health risk assessment of heavy metals in black tea infusion by Monte Carlo simulation.

Tea leaves and their infusion have been interested in the populations because of their therapeutic and relaxing effects. However, tea plant is prone to heavy metals' bioaccumulation. Regarding the high consumption of tea infusion, concentration of arsenic, cadmium, and lead in black tea infusion was determined by inductively coupled plasma mass spectrometry. Tea infusion was prepared by addition of 45 mL deionized water to 1 g tea leaves followed by heating at 90°C for 10 min. After analysis, carcinogenic and noncarcinogenic risks of heavy metals were investigated by Monte Carlo simulation in two age groups of children and adults younger and older than 15 years old, respectively. According to the results, Hazard Quotient (HQ) of three heavy metals in both children and adults was equal and lower than 0.01. Furthermore, incremental lifetime cancer risk (ILCR) of arsenic in Iranian black tea consumers (<1.5 × 10-6) and lead in all consumers (about 2.55 × 10-7) was within the acceptable range introduced by US EPA (≤10-6). ILCR of arsenic in children and adults consuming foreign tea infusion was within the range of 10-6-10-4. Our further investigation revealed that the highest area (75%-85%) of cumulative frequency distribution for arsenic ILCR in foreign tea consumers was related to ILCR ≤10-5 which is the acceptable range determined by the World Health Organization. Therefore, there was no serious concern about the intake of heavy metals by tea infusion in Iranian children and adults.

Physicochemical Analysis and Phytochemical Evaluation of Gokshuradi Churna and its Hydro-Alcoholic Extract

Drug is an essential tool of a physician included in Chatushpada. Many single as well as compound drugs are mentioned in classics in different contexts for internal as well as external use. It is always the cumulative impact of all the ingredients in the solution that plays a critical role in therapeutics, rather than the action of the individual medication. Synergistic action, combined action and toxicity neutralizing action and basic purpose are envisaged to serve drug combinations. One such important formulation prescribed in the Ashtanga Haridya Uttartantra is Gokshuradi Churna provides specifics of the drugs Gokshuradi Churna which was chosen for study. Acharya Vaghbhatta in Uttartantra listed numerous drugs that are useful in the treatment of Alpa, Dushta Retas that specifically influence the properties of Shukrajanana (spermatogenesis) and Shukra Shodhana. This formulation consists of five ingredients i.e., Gokshura (Tribulus terrestris Linn), Ikshura (Asteracantha longifolia Nees), Mash (Phaseolus mungo Linn), Atmagupta seeds (Mucuna prurita Hook) &amp; Shatavari (Asparagus racemosus Wild). Many formulations are available in various texts under the same name Gokshuradi Churna with different ingredients and different Rogadhikara. Keeping this aim into consideration, the present study was designed to scientific evaluation of Gokshuradi Churna and its hydroalcoholic extract on different analytical and phytochemical parameters. The study includes macro and microscopic characters, powder microscopic characteristics, heavy metals analysis and High Performance Thin Layer Chromatography fingerprints (HPTLC). The information generated by this particulars study provides relevant pharmacognostical and physicochemical data needed for proper identification and authentication of Gokshuradi Churna and its hydroalacoholic extract.

Assessing Heavy Metal Contamination in Commonly Used Fertilizers for Polyculture Fish Ponds and Its Implications for Human Health: A Comprehensive Investigation.

Over-fertilizing fish ponds can cause pollution, introducing heavy metals into the food chain and posing health risks. The present study investigated the incidence of heavy metals (Pb, Cu, Cd, and Cr) in commonly applied fertilizers, including nitrogen, phosphorus and potassium (NPK), triple superphosphate (TSP), and di-ammonium phosphate (DAP), and their association with heavy metals in water, sediment, and cultured fish species (Catla catla, Labeo rohita, and Cyprinus carpio) in polyculture fish ponds. The study was conducted over 4months, with four groups in triplicates: control (no fertilizer), group 1 (NPK), group 2 (TSP), and group 3 (DAP). Heavy metal analysis was carried out using atomic absorption spectrophotometry before and after fertilizer application. Significantly (p < 0.05) higher levels of heavy metals were observed in water and sediment after applying fertilizers, with the most pronounced results in group 3 (DAP) followed by group 2 (TSP). The concentration of heavy metals was significantly (p < 0.05) higher in group 3 (DAP) fertilizers compared to other groups. Compared to the control, the concentration and bioaccumulation of heavy metals were significantly (p < 0.05) higher in the fertilizer-applied groups, with notably higher levels in group 3 (DAP). Cluster analysis and the correlation matrix did not show any significant association between the heavy metals and the fertilizers, indicating a complex interplay between the biotic and abiotic factors of the system. The health index (HI) value was < 1 in fish muscles of all studied groups, indicating the fish are safe for consumption. The study recommends monitoring and regulating fertilizer use, especially DAP, to prevent heavy metal contamination, and exploring sustainable alternatives to minimize environmental and health risks.

Influence of localized sources and meteorological conditions on dry-deposited particles: A case study of Gabès, Tunisia

This study investigates the spatial and temporal variations of dry-deposited particles on the surface (by turbulence or gravity) in various sites within Gabès city and its surroundings, South-eastern Tunisia. Monthly samples were collected from five distinct locations: suburban-industrial (S2), suburban-residential (S3), and urban sites (S1, S4, and S5). The average monthly particle deposition flows ranged from 7.35 ± 4.24 g/m2 to 14.41 ± 6.09 g/m2, with the suburban-industrial site (S2) exhibiting the highest deposition rates. They are lower than the reference value of 30 g/m2 in the AFNOR NF-X43-007, but much higher than the Swiss OPair standard (6 g/m2). Compared to the German standard (TALUFT; 10.5 g/m2), only S2 showed significant exceedances. Hierarchical cluster analysis revealed notable statistical affinities among the study sites. Heavy metal analysis indicated fluctuating concentrations across sites, with Zn being the most abundant, followed by Pb, Cu, Ni, and Cd. The enrichment factor (EF) and geoaccumulation index (Igeo) suggested varying degrees of contamination and pollution, highlighting the impact of anthropogenic sources. The findings underscore the need for targeted mitigation strategies to address particle deposition and heavy metal contamination in Gabès and similar regions globally.

Pollution Characteristics, Risk Assessment, and Source Analysis of Heavy Metals in Soil from a Typical Abandoned Antimony Smelting Factory

Considering the surface soil （0-20 cm） from a typical abandoned antimony smelting factory area in Dachang Town, Qinglong County, Guizhou Province, as a case study, a total of 14 soil samples were systematically collected from both within and outside the smelting factory area. The analysis focused on the pollution status, distribution characteristics, and potential ecological risks of heavy metals such as Sb, As, Cd, Cr, Pb, Cu, Zn, Ni, and V in the soil. Additionally, an evaluation and analysis of pollution sources were conducted. The results showed that the mean concentrations of heavy metals including ω（Sb）, ω（As）, ω（Cd）, ω（Cr）, ω（Pb）, ω（Cu）, ω（Zn）, ω（Ni）, and ω（V） in the surface soil of the abandoned antimony smelting factory ranged from 4.58 to 15 049.33 mg·kg-1. With the exception of Cr and Ni, all values exceeded the background values of soils in Guizhou province. The single factor pollution indices of Sb and As were 83.61 and 7.01, respectively, indicating severe contamination. In contrast, Pb fell within the non-polluted to slightly polluted range. The comprehensive potential ecological risk of soil heavy metals was characterized by severe potential ecological risk levels for Sb, As, and Cd, while the remaining heavy metals fell within a range of moderate to substantial potential ecological risk levels. The assessment of the geoaccumulation index revealed that the soil in the study area was primarily contaminated by Sb and As, predominantly exhibiting contamination levels ranging from moderate to severe. The results from the RAC method suggested that Sb was the dominant focus for remediation in this abandoned smelting factory. The two primary pollutants, Sb and As, exhibited elevated levels in leachate toxicity, acid-soluble fraction, available fraction, gastric phase, and intestinal phase in terms of bioavailable content, indicating a certain potential hazard. Further, correlation analysis indicated a certain correlation between the total amount of heavy metals and leachate toxicity, available fraction, acid-soluble fraction, reducible fraction, oxidizable fraction, gastric phase extractable fraction, and intestinal phase extractable fraction. The APCS-MLR model indicated that the sources of Sb, As, Zn, Cu, and Cd were primarily industrial, while the sources of Cr and V were mainly natural, and Pb originated mainly from mixed sources.