Heavy Metals Cr Research Articles

Effect of Lead and Chromium on the Toxicity of Glyphosate Herbicides to African Catfish Clarias Gariepinus (Burchell 1822)

There is a growing increase in pollution of the aquatic ecosystems with a wide range of chemicals including herbicides and heavy metals input through anthropogenic activities, leading to disruption of ecological balance. This study used a static toxicity bioassay to examine the interaction between heavy metals (Pb and Cr) and organophosphorus herbicides (analytical grade glyphosate, commercially formulated - Roundup and Forceup) on African catfish (Clarias gariepinus BURCHELL 1822). Lethal concentrations (LC50) for roundup (RU), forceup (FU), analytical grade glyphosate (AGG), chromium (Cr), and lead (Pb) were 17.23 mg/l, 4877 mg/l, 131.12 mg/l, 21.16 mg/l, and 74.82 mg/l respectively. In addition, fish exposed to varying concentration of chromium (5.0 mg/l and 7.5 mg/l) and lead (20 mg/l and 25 mg/l) with glyphosate (RU: 10 mg/l; FU: 4300 mg/l; and AGG: 100 mg/l) for 96 hours were examined for biochemical parameters. Blood plasma examined for liver and kidney profile indices showed that kidney functions’ parameters (protein, albumin, AST-aspartate aminotransferase, ALT-alanine aminotransferase and Bilirubin) and liver functions parameters (urea and creatinine) increased significantly (p<0.05) when glyphosates combined with lead and chromium treated groups compared with the control group. This study therefore, showed that low concentrations of combined toxicants of glyphosates and heavy metals (Cr and Pb) will synergistically induce deleterious effects on the liver and kidney of Clarias gariepinus.

Composition of heavy metals in sediment, water, and fish of the Ganga and Yamuna Rivers in two major cities of India.

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.

Phytoremediation mechanism and role of plant growth promoting rhizobacteria in weed plants for eco-restoration of hazardous industrial waste polluted site: a review.

Plants have numerous strategies for phytoremediation depending upon the characteristic of pollutants. Plant growth promoting rhizobacteria (PGPR) are essential to the process of phytoremediation and play a key part in it. The mechanism of PGPR for phytoremediation is mediated by two methods; under the direct method there is phytohormone production, nitrogen fixation, nutrient mineral solubilization, and siderophore production while the indirect method includes quorum quenching, antibiosis, production of lytic enzyme, biofilm formation, and hydrogen cyanide production. Due to their economic and environmental viability, most researchers have recently concentrated on the potential of weed plants for phytoremediation. Although weed plants are considered unwanted and noxious, they have a high growth rate and adaptability which opens a high scope for its role in phytoremediation of contaminated site. The interaction of plant with rhizobacteria starts from root exudates containing various organic acids and peptides which act as nutrients essential for colonization and siderophore production by the rhizospheric bacteria. The rhizobacteria, while colonizing, tend to promote plant growth and health either directly by providing phytohormones and minerals or indirectly by suppressing growth of possible phytopathogens. Recently, several weed plants have been reported for phytoextraction of heavy metals (Ni, Pb, Zn, Hg, Cd, Cu, As, Fe, and Cr) contaminants from various agro-based industries. These potential native weed plants have high prospect of eco-restoration of polluted site with complex organo-metallic waste for sustainable development.

Porphyrin nanoparticles-based portable smartphone platform for visual monitoring heavy metal Cr (Ⅲ) in the environment

Chromium ions exist in various valence states in the environment, and their pollution poses serious harm to social ecology and human health. The existing detection is mostly focused on Cr6+, while the detection related to Cr3+ is often overlooked. Cr3+ has a certain impact on soil, water, and the growth of animals and plants and even disrupts ecological balance. Accordingly, it is necessary to explore sensitive, convenient, and fast detection devices for Cr3+ in the environment. Here, we have designed a ratio fluorescence probe with porphyrin nanoparticles formed by block copolymers as the sensing core for ultra sensitive detection of Cr3+. The porphyrin nanoparticles can effectively bind with Cr3+ to form metal complexes, leading to ligand metal charge transfer (LMCT), which will result in a significant color change of the probe from red to blue. Furthermore, we have developed two portable fluorescence sensors for Cr3+ in soil and water, respectively. These portable sensing platforms based on designed nanoprobes and smartphones can convert the color information of fluorescent photos into digital information for real-time analysis. Thus, the method reported in this article can provide a possibility for rapid on-site and visual inspection of Cr3+ in soil and water from different regions.

Source Apportionment and Health Risk Assessment of Heavy Metals in Dust Around Bus Stops in Kaifeng City Based on APCS-MLR Model

In order to reveal the influence of urban transportation systems on the quality of urban ecological environment, this study selected surface dust from bus stops, which is strongly disturbed by transportation, as the research object. The contents of eight heavy metals (V, Cr, Co, Ni, Cu, Zn, Cd, and Pb) in the dust were determined through inductively coupled plasma mass spectrometry (ICP-MS) and inductively coupled plasma atomic emission spectroscopy (ICP-ASE). The spatial distribution characteristics and pollution levels of the eight heavy metals in the dust were analyzed using the geo-accumulation index method. A combined qualitative (correlation analysis and principal component analysis) and quantitative (absolute principal component scores-multiple linear regression model (APCS-MLR)) method was used to explore the sources of heavy metals in surface dust near bus stops. The spatial distribution characteristics of heavy metals from different sources were elucidated using the Kriging interpolation method. The health risk assessment model proposed by the United States Environmental Protection Agency was used to evaluate the human health risks. The results showed that the average values of ω(V), ω(Cr), ω(Co), ω(Ni), ω(Cu), ω(Zn), ω(Cd), ω(Pb), and ω(As) in the bus stop surface dust were 68.36, 59.73, 5.81, 19.34, 40.10, 208.32, 1.01, and 49.46 mg·kg-1, respectively. The concentrations of heavy metals (Cd, Zn, Pb, Cu, and Cr) in the dust were all higher than the background values in the surrounding dust, exceeding them by 3.37, 2.70, 2.01, 1.95, and 1.28 times, respectively. The order of the geo-accumulation index for the eight heavy metals was Cd > Zn > Pb > Cu > Cr > V > Ni > Co, with Cd, Zn, Cu, and Pb in the dust indicating mild pollution levels and the others showing no pollution. The source analysis results showed that Cr, Co, and Ni were natural sources, whereas Cu, Zn, Pb, and Cd were traffic sources, and V was derived from a combination of industrial and natural sources. The APCS-MLR results indicated that the average contribution rates of the four sources were as follows:natural source (34.17 %), traffic source (29.84 %), industrial-natural mixed source (14.64 %), and unknown source (21.35 %). The spatial distribution map of the contribution rate of the traffic source was consistent with the trends of traffic volume and bus route density distribution. According to the health risk assessment, the cancer risk and non-cancer risk for children were both higher than those for adults. Cr was the main non-cancer factor, and Cd was the main cancer-causing factor. Natural and traffic sources contributed the most to non-cancer risk and cancer risk, respectively.

Removal of trivalent chromium ions in model contaminated groundwater using hexagonal boron nitride as an adsorbent

The feasibility of using hexagonal boron nitride (h-BN) to treat heavy metal Cr(III) from model contaminated groundwater was evaluated in this study by adsorption experiments and characterizations. To the best of our knowledge, this study is the first attempt to conduct the adsorption of Cr(III) by h-BN under various experimental conditions such as exposure time, ratio of adsorbates and adsorbents, solution pH, background ions with different ionic strength, and the presence of humic acids (HA) in model contaminated groundwater. The optimized h-BN showed excellent maximum adsorption capacity (i.e., 177 mg ∙ g−1) when the concentrations of Cr(III) and h-BN were 10 and 10 mg ∙ L−1, respectively. Subsequently, we confirmed there was a negligible change in the adsorption performance of Cr(III) by h-BN in the presence of co-ions (i.e., K and Mg) in concentrations in a range from 50 to 1000 mg ∙ L−1. Furthermore, the adsorption performance of Cr(III) gradually improved with HA concentrations from 2.5 to 25 mg ∙ L−1. Interestingly, the maximum adsorption performance of Cr(III) by both HA and h-BN increased until 500 mg ∙ g−1 in the presence of 25 mg ∙ L−1 HA. The adsorption mechanism was clarified by Fourier-transform infrared spectroscopy and X-ray photoelectron spectroscopy. Additionally, we successfully confirmed that h-BN could be reused until five cycles. On the basis of the adsorption performance results and characterizations, h-BN can be utilized as an efficient and practical adsorbent to treat Cr(III) in groundwater treatment.

Influence of vegetation on heavy metal Cr release process from bottom sediment under unidirectional flows and regular waves

As human activities become more intensive, a substantial number of heavy metals are discharged into estuarine or wetland environments. Due to the poor degradability, heavy metals are prone to adsorption and deposition on suspended particles in bottom sediments. Subsequently, under the influence of disturbances, there is a potential for their re-release, causing secondary pollution. To investigate the release process of the heavy metal Cr from sediment, laboratory experiments were conducted under both unidirectional flow and regular wave conditions. At the initial stage, the temporal trends of particulate (CrP) and dissolved (CrD) Chromium concentrations were both characterized by initial increments followed by stabilization and continuous escalation. Vertically, the stable concentrations of CrP and CrD increased with the presence of vegetation and the enhancement of hydrodynamics. The Elovich equation, pseudo-second-order kinetic equation, Double constant equation (Freundlich model), and parabolic diffusion equation were employed to predict the release process of CrD from bottom sediment. The Elovich equation proved most suitable for describing the release process of CrD, with an R2 exceeding 0.9. In order to assess the influence of vegetation on the Cr release process, the Stem-Reynolds were introduced to modify the Elovich equation. The final maximum error was 12 % (excluding the initial stage), which was much lower than that using the original Elovich equation (maximum error of 32 %). The study findings provide practical support for estuarine and wetland managers to formulate effective heavy metal management measures, which contribute to the conservation and sustainable management of aquatic ecosystems.

Estimation of heavy metals in sediments and aquatic plant species in two rivers of Punjab, Pakistan

This research highlights the distribution of heavy metals (Ni, Cu, Zn, Cr, Co and Mn) in Ravi and Chenab and assesses their effect on ecosystem health. Samples of plant species and sediments at eight sampling sites were collected and analysed by the PIXE technique. Heavy metal concentrations (µg/g) of Zn (7.98–411.23), Ni (12.59–209), Cu (3.74–38.77) and Mn (0–730.21) in river Ravi and concentrations of Zn (49.32–274.30), Ni (1.05–141.21) and Mn (41.66–519.47) in river Chenab were found to be high but Heavy metal concentration in the two compartments were in the following order plants > sediments. Heavy metals of sediments and plants depict that there are significant correlations between Cu (0.994), Zn (0.986) and Cr (0.978) in river Ravi and Ni (1.000), Zn (.990) and Cr (.978) in river Chenab. The results show the potential of heavy metals from plants in two rivers of Pakistan.

Pollution assessment and index properties of Okpulor soils, Rivers State, Nigeria: geochemical characterization, geotechnical and geoenvironmental implications

This study assessed soil pollution and index properties in Okpulor through geochemical, geotechnical, and geoenvironmental analyses. Twenty samples, comprising 14 surface and 6 shallow subsurface ones, underwent geochemical analysis for heavy metals (Fe, Cr, Cu, Zn, Ni, and Pb). Five geochemical indices, including the Geoaccumulation Index (Igeo), Enrichment Factor (EF), Contamination Factor (CF), Metal Pollution Index (MPI), and Potential Ecological Risk Index (PERI), were utilized. Simultaneously, six subsurface samples underwent geotechnical analysis for Natural Moisture, Grain Size, Specific Gravity, Bulk Density, and Atterberg Limits, following Unified Soil Classification System (USCS) and American Association of State Highway and Transportation Officials (AASHTO) guidelines. The Igeo highlighted significant heavy metal contamination in Okpulor soils, particularly Cd. EF values exceeding 1.5 underscored a strong anthropogenic influence, with CF indicating Cd's substantial contribution to overall contamination. PERI underscored the ecological risks associated with Cd contamination. Natural moisture content, ranging from 18.21% to 21.45%, indicated a notable presence of water in the soil during the dry season, potentially leading to increased leaching and migration of water-soluble contaminants. Bulk density values suggested moderate to lightly packed soils, impacting porosity and permeability, and influencing contaminant movement. Atterberg limits indicated low soil plasticity, impacting moisture retention and contaminant behaviour. Grain size analysis revealed poorly graded soils with a close sand-to-clay ratio, affecting water drainage. These geotechnical properties and heavy metal contamination reveal the intricate interplay between soil characteristics and contamination risks in the Okpulor area, emphasizing the need for targeted interventions to safeguard the environment.

Assessment of metals and metalloids agglutinated to airborne suspended particulate matter in selected plant species during the pre-and post-monsoon in the urban area

The elemental accumulation has emerged as a major environmental concern due to various anthropogenic sources such as vehicles, road dust, and industrial activities, contributing to the agglutination of elements to airborne Suspended Particulate Matter (SPM). SPM-bound elements accumulate on plant surfaces impact air quality and human health due to their noxiousness. Therefore, plants' ability to capture and mitigate air pollutants plays a crucial role in urban areas. This study aimed to investigate the levels and distribution of twenty-six elements, comprised of heavy metals (Cd, Pb, Cr, Cu Zn, Co, Ni, Fe, Mn, Ag, Mo, V, Ga, and Bi), light metals (B, As, Te, and Se), and metalloids (Al, Li, Sr, K, Mg, Na, Ca, and Ba) accumulated on the surface and inside the leaves of dominant plant species during the pre-and post-monsoon at six categorized (commercial, traffic-prone, residential, educational, greenbelt and industrial areas) locations in Delhi, India. In addition, the Metal Accumulation Index (MAI) was determined, and the statistical analysis was conducted using two-way ANOVA, Principal Component Analysis (PCA), and Hierarchical Cluster Analysis (HCA). In the pre-and post-monsoon, two-way ANOVA revealed significant differences (P < 0.05) in metal concentrations. During the pre-monsoon plants exhibited the highest metal accumulation (∼21%) at the Anand Vihar (commercial) in Delhi, with the maximum average concentrations of Cr (118.25 mg/kg), Cu (204.38 mg/kg), Zn (293.27 mg/kg), and Fe (2721.17 mg/kg). Ficus benghalensis L exhibited the maximum 213.73 MAI at the Anand Vihar in the pre-monsoon. Ni and Cr indicated the highest correlation (P < 0.05, r = 0.82) in the PCA test. HCA test revealed similarity (∼87.7%) at ITO (traffic-prone) and Okhla Phase-2 (industrial) in F. religiosa regarding metal concentration patterns. Findings highlighted seasonal elemental pollutants uptake dynamics of plant species and explored species-specific metal accumulation, revealing potential implications of metal-tolerant plants for urban greenbelt.

Performance of the silica adsorbent from snake fruit peel for removing heavy metals of Ag, Cu, Mn, and Cr in SCW

Silver crafts wastewater (SCW) typically contains environmentally harmful heavy metals, including Ag, Cu, Mn, and Cr, necessitating treatment before disposal. This study explores a promising solution using silica (SiO2) adsorbents derived from snake fruit peel through acidic activation with HCl concentrations of 2, 4, and 6 M. Qualitative analysis of the adsorbent involved Fourier-transform infrared spectrometer (FTIR) and x-ray fluorescence (XRF) techniques. XRF analysis revealed major compositions of Si (26%) and Cl (71.46%), with minor elements such as Ca (0.91%), P (0.42%), K (0.37%), Fe (0.12%), and others. FTIR analysis indicated the presence of siloxane (Si-O-Si) and silanol (Si-OH) on the adsorbent. The SiO2 adsorbent demonstrated effectiveness in removing heavy metals (Ag, Cu, Mn, and Cr) from SCW, achieving removal percentages of approximately 16.96%, 24.38%, 19.34%, and 9.82%, respectively. This research contributes to the development of an environmentally friendly approach for SCW treatment using silica adsorbents derived from agricultural waste.

Soil-forming accumulation of heavy metals in geological high background areas: Constraints of structure, lithology, and overlying soil geochemistry

Heavy metals (HMs) are often abnormally enriched in soils in geologically high background areas, posing a serious threat to the ecosystem and human health. However, the material origin of HMs in overlying soils is unclear. In this paper, we studied the accumulation control and formation process of HMs (Cd, Hg, As, Pb, Cr, Cu, Ni, and Zn) in soils overlying bedrock from different geological periods in a typical anticline structure area in southwest of Guizhou province. The results revealed that the content of HMs in the bedrock were ranked as Carboniferous carbonate rocks < Permian carbonate rocks < Triassic clastic rocks, while the opposite trend was observed for the HMs content in the overlying soil. The slopes of the EF-Q values of HMs in the soils overlying the Carboniferous, Permian, and Triassic rocks were 0.003, 0.007, and 0.83, respectively, which suggests that HMs enrichment or leaching was more complicated in the process of carbonate weathering soil-forming, whereas it was mainly in situ weathering during the process of clastic weathering soil-forming. The soils overlying the bedrock of the three geological periods experienced similar weathering processes and had the same source of soil-forming matrices, as it was observed that their Fe2O3-Al2O3, Hf-Zr, Nb-Ta, Th/Sc-Zr/Sc and Y/Ho-Y contents were significantly correlated (with R2 values of 0.80, 0.94, 0.72, 0.60, and 0.76, respectively) with very similar REE assignment patterns. The results corroborated the causes of the high background geological heterogeneity of HMs in the overlying soils in karst areas and supported the theory of the source of weathering soil-forming materials from carbonate rocks in karst areas.

Hyperbranched polymeric membranes for industrial water purification

This work aims at the preparation and characterization of dual-layer (DL) nano-fibrous mat (NFM) of hydrophobic and mechanical stable polyacrylonitrile (PAN) nano-fibers (NFs), as a supporter, and polyamide 6 (PA)/chitosan (Ch) NFs as a top hydrophilic coating layer.PAN and PA fibers, as residual wastes from textile processes, were collected and dissolved in their proper solvents. PAN was electro-spuned under certain conditions of electro-spinning (voltage, flow rate, and distance between spinneret and collector) to obtain PAN-NFM. Different ratios of PA/Ch composite were prepared and then electro-spun above the PAN-NFM that was previously prepared to obtain hydrophobic/hydrophilic functional dual-layer nano-fibrous membrane (DLNFM). The efficiency of the prepared DLNFM for capturing dye residues and heavy metals from wastewater was investigated.The viscosities of the prepared composite solutions were measured. The prepared dual-layer nano-fiber membranes (DLNFMs) were chemically and physically characterized by Fourier transform infrared spectroscopy, scanning electron microscope, X-ray diffraction, and thermogravimetric analyzer. The potential of the prepared mats for the adsorption of some heavy metal ions, i.e., Cu+2, Cr+3, and Pb+2 cations in addition to dyes from wastewater was evaluated. The effect of using different concentrations of PA/Ch composite as well as the thickness of the obtained DLNFM on the filtration efficiency was studied.The results of this study show the success of functional DLNFM in dye and heavy metal removal. The maximum removal efficiency of acid dyes was reached to 73.4 % and of reactive dye was approximately 61 % for PAN/PA-1.25%Ch DLNFM after 3 days at room temperature. The removal efficiency percent of heavy metal ions reached to 54 % by DLNFM. Additionally, the results showed that 0.08 mm is the ideal thickness for maximum absorption capacity. This value is correlated with the membrane's highest Ch percentage, which is (PAN/PA-1.25%Ch). Furthermore, the results demonstrate that the presence of the Ch polymer strengthened the produced bi-layered membrane to achieve the highest thermal stability when compared to the other nano-fibrous membranes (NFMs), with the breakdown temperature of the Ch functionalized dual-layer membranes (DLMs) reaching approximately 617 °C and a maximum weight loss of 60 %.

Adsorption of Cr(VI) and Cr(III) on layered pipe scales and the effects of disinfectants in drinking water distribution systems

Pipe scales in drinking water distribution systems (DWDS) potentially adsorb chromium (Cr). Meanwhile, the fate of Cr in pipe scales and water could be influenced by the disinfectants used in DWDS since they might influence the valence state of Cr. Therefore, the adsorption of Cr (Cr(VI) and Cr(III)) on pipe scales, the transformation between different valence states, and the effects of disinfectants present in DWDS are important research topics for improving tap water quality but have not yet been sufficiently investigated. This study investigated the properties of layered pipe scales and conducted adsorption kinetic experiments in single and binary Cr(VI) and Cr(III) systems, as well as experiments related to the oxidation and adsorption of Cr(III) under the influence of decaying disinfectants. According to the results, pipe scales exhibited distinct layered structures with varying mechanisms for the adsorption of Cr(VI) and Cr(III). Cr(VI) was adsorbed through surface complexation on the surface and porous core layers, while redox reactions predominantly occurred on the shell-like layer. Furthermore, Cr(III) was adsorbed via surface precipitation on the three-layer pipe scales. Importantly, disinfectants promoted the transformation of Cr(III) to the less readily released Cr(VI) in pipe scales, reducing the Cr exposure risk from the pipe scale phase. Pipe scales also decreased the Cr(VI) concentration in water (almost 0 mg/L), enhancing the safety of DWDS. This study provides theoretical guidance on the safe operation of DWDS.

Bioaccumulation of heavy metals in Capoeta tinca fish and health risk assessment

The This study evaluates the potential human health risks associated with five heavy metals (Zn, Pb, Cu, Cd, and Cr) in Capoeta tinca fish. It assesses the heavy metal burden in the muscle, gill, and liver tissues of C. tinca, and estimates the potential health risks for consumers by employing estimated daily intake (EDI) and standard hazard ratios (THQ) related to heavy metal consumption. Fish and water samples were taken from three different Regions as Sincan Brook (Sivas–Hafik), Habeş Brook (Sivas–Zara), and Tozanlı Brook (Sivas–Hafik), Turkey. The heavy metal concentrations in the brook water were found to be higher than the established safe for safety threshold in all the sampling points. Besides that, the values were observed to be lower than the allowed limits. Considering the fish tissues, the Pb, Cd, and Cr concentrations were found to be higher than the safe limits predicted by WHO. The findings indicate that the liver of C. tinca fish exhibited the highest accumulation of heavy metals across all sampling areas. The highest heavy metal concentrations found in fish muscles were found to be (Cu) 2.51 ± 0.91 μg·g-1, (Cr) 0.45 ± 0.03 μg·g-1, (Cd) 0.88 ± 0.04 μg·g-1, (Pb) 2.04 ± 0.03 μg·g-1, and (Zn) 13.12 ± 1.08 μg·g-1. The descending order of heavy metal accumulation in gills was found to be Zn &gt; Cu &gt;Pb &gt; Cd &gt; Cr. Moreover, for each heavy metal, the Bio–concentration factor (BCF) index, Acceptable Daily Intake, EDI, and THQ (&lt;1) values were found to be lower than the limits set in the international standards, indicating that no elements posing a threat to public health were encountered, thus not posing a short–term risk.

Atomic Absorption Spectroscopic Analysis of Heavy Metals in Cancerous Breast Tissues Among Women in Jos, Nigeria

Breast cancer is prevalent in northern Nigerian women most especially Jos, Plateau State owing to anthropogenic activities such as solid earth mineral mining. In this study, Atomic Absorption Spectrometry was used to determine the levels of eight heavy metals (Cd, As, Cr, Cu, Fe, Pb, Ni and Zn) in cancerous and non-cancerous breast tissues of Jos Nigerian Women. The concentration of heavy metals ranged from 1.08 to 29.34 mg/kg, 0.29 to 10.76 mg/kg, 0.35 to 51.93 mg/kg, 5.15 to 62.93 mg/kg, 11.64 to 51.10 mg/kg, 0.42 to 83.16 mg/kg, 2.08 to 43.07 mg/kg and 1.67 to 71.53 mg/kg for Cd, As, Cr, Cu, Fe, Pb, Ni and Zn respectively. Using MATLAB R2016a, significant differences (t&amp;lt;sub&amp;gt;v&amp;lt;/sub&amp;gt; = 0.0041 – 0.0317) existed between the levels of all the heavy metals in cancerous and non-cancerous breast tissues except Fe. At 0.01 level of significance, positive significant correlation existed between Pb and Fe, Pb and Cu, Pb and Fe, Ni and Fe, Cr and Pb, as well as Ni and Cr (r = 0.583 – 0.998) in cancerous breast tissues. Using ANOVA, significant differences also occurred in the levels of these heavy metals in cancerous breast tissues (p = 1.910510×10&amp;lt;sup&amp;gt;-26&amp;lt;/sup&amp;gt;). The relatively high levels of the cancer-induced heavy metals (Cd, As, Cr and Pb) compared with control indicated contamination or exposure to heavy metals which could be the major cause of cancer in these female subjects.

Assessment of genotoxicity of air pollution in urban areas using an integrated model of passive biomonitoring

Atmospheric pollution is a major public health issue and has become increasingly critical for human health. Urban atmospheric pollution is typically assessed through physicochemical indicators aligned with environmental legislation parameters, providing data on air quality levels. While the effects of pollution on sensitive organisms serve as a warning for public health decision-makers, there remains a need to explore the interpretation of environmental data on pollutants. The use of species adapted to urban environments as sentinels enables continuous and integrated monitoring of environmental pollution implications on biological systems. In this study, we investigated the use of the plant species Tradescantia pallida as a biomonitor to evaluate the genotoxic effects of atmospheric pollution under diverse vehicular traffic conditions. T. pallida was strategically planted at the leading urban intersections in Uberlândia, Brazil. During COVID-19 pandemic lockdowns, we compared indicators such as physical, biological, and traffic data at different intersections in residential and commercial zones. The reduction in vehicular traffic highlighted the sensitivity of plant species to changes in air and soil pollutants. T. pallida showed bioaccumulation of heavy metals Cd and Cr in monitored areas with higher traffic levels. Additionally, we established a multiple linear regression model to estimate genotoxicity using the micronucleus test, with chromium concentration in the soil (X1) and particulate matter (PM) in the atmosphere (X2) identified as the primary independent variables. Our findings provide a comprehensive portrait of the impact of vehicular traffic changes on PM and offer valuable insights for refining parameters and models of Environmental Health Surveillance.

Adsorption and distribution of heavy metals in aquatic environments: The role of colloids and effects of environmental factors

The study investigated the distributions of heavy metals (Cd, Cr, Cu, Mn, and Pb) between dissolved fraction (<0.7 µm) and particles (>0.7 µm) during the adsorption process. The dissolved fraction was further separated into truly dissolved (<3 kDa) and colloidal (3 kDa-0.7 µm) fractions. Significant metal adsorption occurred on the colloids, resulting in their aggregation into particles, which in turn influenced the particle adsorption kinetics. Colloids could either accelerate or inhibit the transformation of metal ions into particulates, depending on their stability. Competitive metals for colloids (Pb and Cr) were more susceptible to the effects of colloids than other elements. DOM was the predominant environmental factor influencing colloid behavior. The XDLVO theory showed that DOM enhanced the negative charge of colloids and made the colloid surface more hydrophilic, inhibiting the aggregation of colloids. DOM resulted in substantial increases in the concentrations of colloidal Pb and Cr from 0.31 μg/L and 4.58 μg/L to 20.52 μg/L and 43.51 μg/L, respectively, whereas the increment for less competitive metals (Cd and Mn) was smaller. These findings suggest that the distribution of heavy metals is influenced not only by adsorption from particles and ions but also by the complex dynamics of colloids.

Assessment of dumpsites leachate, geotechnical properties of the soil, and their impacts on surface and groundwater quality of Sunyani, Ghana

Leachate from sanitary landfill and dumpsites have potential to cause soil and groundwater contamination, and disrupt ecosystems. However, there is little information about dumpsite leachates and geotechnical properties and their impacts on surface and groundwater in Bono region, Ghana. This study assessed dumpsites leachate, geotechnical properties of the soil, and their impacts on surface and groundwater quality in Sunyani. Six triplicate leachates, eleven triplicate groundwater and three triplicate surface water samples were taken at (up-stream, mid-stream and down-stream) urban dumpsite, and eight triplicate groundwater samples taken around peri-urban dumpsite. Water samples were stored (<4°C) in polyethylene bottle for laboratory analysis. Physicochemical properties of leachate and water samples were analyzed using standard methods. Heavy metals (Cd, Hg, Pb, Zn, Cr, Fe, Cu, and Ni) were determined using atomic absorption spectroscopy. Water quality index (WQI) and leachate pollution loads (LPL) were investigated, while plasticity index (Ip) and liquid index (Il) were determined using Atterberg limit test. The results showed that all leachate samples were heavily polluted with mean concentrations of chlorides ranged between (2830±220 and 63810±340), biochemical oxygen demand (358±36 to 820±80), ammonium ions (82.8±2.2 to 267.6±62), and cadmium (0.49±0.02 to 5.32±1.0); with their leachate pollution index (LPI) and LPL exceeding their leachate disposal standards (LDS>100). WQI ranged from 6.51 to 289, indicating excellent to heavily polluted groundwater sources. Surface water was heavily polluted with WQI between 0.84 and 776.75, with majority having WQI>100. The heavily polluted samples were located 75-155 m away from urban dumpsite. Moderate significant negative association was established between (WQI-P and WQI-H) and distance with multiple R2=0.4709, p=0.0191 and R2= 0.4482, p=0.02425 respectively. Statistically, strong significant negative association between (WQI-P & WQI-H) and Ip (p < 0.05). This implies that when plasticity index and distance from groundwater sources to dumpsite increased, WQI values decreased, and groundwater quality improved.

Simultaneous Removal of Setazol Navy Blue and Cr(VI) By Mixed Microbial Culture Isolated from the Çubuk Stream

Water samples taken from the Çubuk Stream (Ankara, Turkey) were inoculated into nutrient broth media containing Setazol Navy Blue SBG (SNB), an organic pollutant, and heavy metal Cr(VI), an inorganic pollutant, to obtain a pollutant-resistant mixed microbial culture. Experiments were conducted with this culture to remove SNB and heavy metal. The optimum conditions, where the mixed bacterial culture removed the pollutants most effectively, were determined, showing that the highest capacity for removal took place at pH 8 with removal percentages 96.3% for Cr(VI) and 78.5% for SNB. In media with 50.4 mg/L SNB and 9.7 mg/L Cr(VI), the SNB removal was 87.3%, and the Cr(VI) removal was 96.6% at the end of the 7-day incubation period. The highest removal was observed with a biomass concentration of 8% (v/v) of mixed culture [50 mg/L SNB dye+25 mg/L Cr(VI)]. The removal was 100% for both Cr(VI) and the SNB dye. The bacteria with the highest removal were isolated and identified using 16S rDNA gene sequence analysis as Microbacterium oxydans and Leucobacter aridicollis. The role of various functional groups and the structures of the microorganisms that might be involved in the removal mechanisms were discussed using their FTIR spectra. This report is the first study that investigates a mixed bacterial culture and pure cultures (M. oxydans and L. aridicollis) isolated from that mixed culture, removing both SNB and Cr(VI) simultaneously.