Mean Concentrations Of Metals Research Articles

Pollution and risk assessment of heavy metals in water, sediment and fish (Clarias gariepinus) in a fish farm cluster in Niger Delta region, Nigeria.

The study determined the following heavy metals: cadmium (Cd), chromium (Cr), copper (Cu), manganese (Mn), lead (Pb) and zinc (Zn) concentrations in surface water and in fish pond (water, sediments and farmed fish (Clarias gariepinus)) from a fish farm cluster with the view of assessing its pollution level and associated human health exposure risk to these heavy metals through fish consumption. Samples were digested with aqua regia and metal concentrations were determined with an atomic absorption spectrophotometer equipped with an air acetylene flame. Mean concentrations of the heavy metals (ppm) in surface and pond water ranged as follows: cadmium (below detection limit (bdl): 0.298); chromium (bdl: 0.257); copper (bdl: 0.067); manganese (bdl: 0.163); lead (bdl: 0.736) and zinc (bdl: 0.078) while in sediment, the ranges (mg/kg dry weight) were as follows: cadmium (1.156-3.329); chromium (9.439-14.373); copper (26.710-121.819); manganese (3.143-37.202); lead (0.340-1.537) and zinc (87.681-371.060). The mean concentrations of the metals in surface water were significantly different (p < 0.05) from those in sediment in all the sampling sites. The mean metal concentrations (mg/kg dry weight) in C. gariepnus were in the following ranges: cadmium (0.733-1.405); chromium (0.593-1.692); copper (175.882-245.321); manganese (bdl: 3.326); lead (0.221-0.263) and zinc (248.191-292.333). Some of the heavy metal concentrations obtained in water, sediment and catfish analyzed were above the permissible limit set by some National (DPR) and International organisations (WHO, FEPA and FAO). The pollution studies showed that lead, cadmium and chromium contaminated the surface water samples. Sediment from all sites showed low to considerable contamination by the heavy metals. The human exposure risk assessment of the metals showed that the total hazard index was less than one which indicates no probable adverse health effect from the consumption of fish from the ponds, although this case is different for Pb since there is no estimation of oral reference dose (RfDo) for lead according to EPA.

Composition and human health risk analysis of elements in muscle tissues of wild and farmed fish species from Northeast Mediterranean

It was aimed to determine the concentrations of several heavy metals in muscle tissues of 18 wild and 2 farmed fish species obtained from 6 stations and 3 different fish farms, which were located between Hatay and Antalya provinces in the Northeast Mediterranean. The metal analysis of tissue samples was conducted using the Inductively-coupled Plasma Mass Spectrometry (ICP-MS) method. Given all the tissue samples, the mean metal concentrations were found to be as follows; Li: < 0.001–0.15 mg kg−1 ww, Al: < 0.0006–2.54 mg kg−1 ww, Cr: < 0.001–0.49 mg kg−1 ww, Mn: < 0.0002–1.05 mg kg−1 ww, Fe: < 0.001–0.02 mg kg−1 ww, Cu: < 0.006 – 1.30 mg kg−1 ww, Zn: 1.76–15.4 mg kg−1 ww, As: 0.52–35.1 mg kg−1 ww, Sn: < 0.0004–2.04 mg kg−1 ww. Co, Ni, Cd, and Pb were found to be lower than the detectable limits in all tissue samples. For human consumption estimated weekly intakes (EWI), target hazard quotients (THQ), and cancer risk (CR) levels of the metals were determined in muscle tissues of the wild and farmed fish species. The mean EWI, THQ, and CR levels for As were found 34.82, 3.97E+ 00 ± 4.84E+ 00 and 1.06–03 ± 1.30E-03 for wild species while these values for farmed species were as follows; 2.46, 2.80E-01 ± 1.18E-01 and 7.49E-05 ± 3.15E-05 respectively. When compared to the wild species, metal levels were significantly lower in farmed fishes and consuming these fishes was determined not to cause any health problems. For the wild samples, however, inorganic As concentrations were found to be risky from carcinogenic and non-carcinogenic aspects. Moreover, the mean metal concentrations in muscle tissues of fishes obtained from the Northeast Mediterranean were compared to the national/international codex limits and it was found that all the metal concentrations in tissue samples were lower than the upper limits set by Turkish Food Codex (TFC), European Union (EU), and World Health Organization (WHO).

Spatial Distribution of Black Soot and Its Health Effects in Port Harcourt Metropolis, Nigeria

This research presents a novel approach to assessing the health implications of black soot using a MiniVol air sampler. The MiniVol air sampler was used to collect PM from the ambient air at six monitoring sites in Port Harcourt, Nigeria. Sampling was conducted every day for seven days, for 24 hours. PM2.5 concentrations at Uniport Junction, GRA Junction, Slaughter Roundabout, Abuloma Jetty, Rumuomasi Roundabout, and New Road Borokiri were 38.6 g/m3, 28.3 g/m3, 93.7 g/m3, 72.9 g/m3, 30.6 g/m3, and 31.3 g/m3, respectively. PM10 concentrations ranged from 71.2 g/m3 to 60.6 g/m3, with 103.3 g/m3, 85.5 g/m3, 40.1 g/m3, and 35.2 g/m3 being the highest. The level of PM2.5 and PM10 pollution in the ambient air was high across the six sampling sites, with mean PM2.5 and PM10 concentrations exceeding the WHO (2011) guideline. The flame atomic absorption spectrometry (FAAS) technique was used. The presence of heavy metals, such as mean metal concentrations of lead, cadmium, chromium, mercury, and nickel, ranged from 0.009 g/m3 -0.532 g/m3, 0.002 g/m3 - 0.544 g/m3, 0.002 g/m3 -0.338 g/m3, 0.001 g/m3, and 0.001 g/m3 -0.432 g/m3, across the six sampling sites. The GC-MS was used to determine the presence of PAHs in particulate matter. Correlation results revealed a strong positive correlation between PM2.5 and PM10. The findings also revealed a positive relationship between the metals as well as between the metals and PAHs, resulting in asthma, lung cancer, breathing difficulties, and miscarriages among pregnant women, which have affected the health implications of the people living in the environment.

Evaluation of metals contamination using ecological quality indices in the Nayband bay (Northern Persian Gulf, Iran): As one of the biggest petrochemical regions in the world

The present study has investigated the metals contamination (Fe, Ni, V, and Co) using ecological risk indices, source identification, and spatial distribution in Nayband bay, north of the Persian Gulf, Iran A total of 20 sediment samples were collected from Nayband bay, and the heavy metals contents of sediments were determined using Inductively Coupled Plasma Mass Spectrometry (ICP-MS). The mean concentration of metals varied from 7990.97 ±3913.09μg/g (Fe), 19.71 ±8.60μg/g (Ni), 14.90 ±5.87μg/g (V), and 5.71 ±2.29μg/g (Co). The enrichment factor (EF) values for studied metals were obtained between no enrichment to moderate enrichment. The geoaccumulation index revealed low pollution of Fe, V, and Co, and mild to moderate pollution of Ni. The potential ecological risk index indicated that all analyzed metals had a low ecological risk in all studied sampling sites. All studied metals presented significant correlation (99% confidence level) with each other (P <0.01). Principal component analysis (PCA) disclosed that metals in the sediments emanated from natural and anthropogenic sources, respectively. Atmospheric deposition was the main source of Co derived from industrial activity, while Ni and V were mainly released from shipping and sewage wastewater. In conclusion, petrochemical developments in the Persian Gulf have put a serious pressure on unique ecosystems like Nayband Bay, and more efforts should be made to alleviate the adverse effects of industrial contaminants in this region.

Assessment of Carcinogenic and Non-carcinogenic Risk of Exposure to Metals via Consumption of Coffee, Tea, and Herbal Tea in Iranians.

In the current study, we assessed health risk posed to Iranian consumers through exposure to metals via oral consumption of coffee, tea, and herbal tea of various trademarks collected from Iran market. Level of As, Cd, Cr, Cu, Fe, Hg, Ni, and Pb in 243 samples was quantified by inductively coupled plasma-optical emission spectrometry (ICP-OES). The metal levels in coffee samples from different trademarks of a specific country had statistically similar levels of metals; however, metal levels differed significantly among brand names form different countries. Metal levels in tea samples differed significantly between domestic and imported products, while different trademarks of similar countries did not show significant variations in this respect. Metal level in herbal tea samples did not show significant variations among different trademarks. Nevertheless, it should be highlighted that mean concentrations of metals statistically differed among different herbal tea samples. Deterministic hazard quotients (HQs) were <1.0 for all non-carcinogenic metals and total hazard index (HI) values indicated no risk; however, probabilistic assessment calculated HI values >1. In both deterministic and probabilistic scenarios, carcinogenic metals As and Ni had an estimated incremental lifetime cancer risk (ILCR) of medium level while that of Pb indicated no cancer risk. Sensitivity analysis showed that the concentration of metals had the most significant effect on non-carcinogenic and carcinogenic risks.

Metal Release and Surface Degradation of Fixed Orthodontic Appliances during the Dental Levelling and Aligning Phase: A 12-Week Study

The purpose of the present study is twofold: (i) to assess the salivary nickel, chromium, and iron concentrations and (ii) to characterize the surface microstructure of the typical commercially available Ni-containing metallic appliances during the first 12-week orthodontic treatment period. A total of 85 unstimulated saliva samples were collected from patients before treatment, after 2 days, and after 1, 4, and 12 weeks. Salivary ion concentrations were determined by inductively coupled plasma optical emission spectroscopy, and data were analyzed with the Statistical Package for Social Sciences (IBM SPSS) software. The recorded mean metal concentrations were in the ranges of 132–175 µg/L for Ni, 171–192 µg/L for Cr, and 826–1023 µg/L for Fe. No statistically significant variations were observed between the different study times, and the null hypothesis (the concentrations of metallic ions in patients’ saliva did not significantly change after the placement of the orthodontic appliances) was accepted (p &gt; 0.05). Mean salivary metallic ions were below toxic levels, and no adverse clinical reactions were registered. The intraoral surface degradation of the fixed components was corroborated by optical microscopy, scanning electron microscopy, and energy dispersive spectrometry. Microstructural analysis after complete orthodontic procedure confirmed different corrosion types, from pitting to biocorrosion.

Heavy Metals Concentration and Arthropod Population in Some Selected Dumpsites from Calabar, Cross River State, Nigeria

The aim of this research is to investigate the influence of refuse dumping on arthropods population and heavy metals concentration in Calabar Cross River state, Nigeria. Soil, and arthropod samples were collected from Lemna, Nassarawa, University of Calabar female hostel and Goldie market dumpsites which were labeled S1, S2, S3, and S4, respectively while same samples were picked from a plot of land labeled PC as a control. Arthropods were identified using light microscope and identification guide while heavy metals Cd, Pb, Cr, Ni, Co, As and Hg were analysed in soil and arthropods using Atomic absorption spectrophotometer (AAS). The results obtained showed 8363 arthropod individuals consisting of 19 species dominated by Muscidae (flies) family which constitutes about 20.39% whose presence indicates high level of pollution of the dumpsite and a possible health implication on people living around the dumpsites because these organisms are vectors for diseases such as yellow fever, malaria, Heavycholera and typhoid fever. Cadmium was the highest occurring heavy metal in dumpsites soil with a concentration of 1.457±0.493 mg/kg in S4 while As was the lowest with a concentration of 0.001 ± 0.000 mg/kg in S1 and Hg was below detection limit in all dumpsites. In arthropods, Cd had the highest occurrence with a concentration of 0.020 ± 0.001 mg/kg in S4 while Pb in S2 and Co in S1 with concentration of 0.001 ± 0.000 each were the lowest occurring metals. Heavy metals concentration in soil and arthropods from the dumpsites was higher than that of the control which shows the influences of refuse dumping and strong (&gt; 5) positive correlation between mean metal concentrations in soil and arthropods suggests that these arthropods can be used as bio-indicators of heavy metals contamination and accumulation. It is therefore recommended that wastes be segregated and proper disposal methods should be adopted.

Metals and metalloids concentrations in three genotypes of pelagic Sargassum from the Atlantic Ocean Basin-scale

Since 2011, the Caribbean Islands have witnessed unprecedented massive stranding of a pelagic brown algal Sargassum spp. inducing damages for coastal ecosystems and economy. By accumulating heavy metals, Sargassum can play a role in contaminant transportation from offshore to the coast. In 2019, three genotypes of Sargassum (S. fluitans III, S. natans I, and VIII) were sampled in seven stations along a 3400 km transect in the Atlantic Ocean. Concentrations of 15 heavy metal(loid)s elements were analyzed by Inductively Coupled Plasma Optical Emission Spectrometer (ICP-OES). Mean metal concentrations were ranked following descending order: As >Fe > Al > Mn > Cd > Zn > Ni > V > Cu > Cr > Hg. The metalloid As was the most abundant contaminant with a maximum value of 115 ppm, previously observed in the Caribbean area (80–150 ppm). At Atlantic Ocean Basin-scale, metallic element concentrations do not present spatial longitudinal gradients. Genotypes S. fluitans III and S. natans (I and VIII), present differents metal(loid)s contamination distinct patterns.

Metals Bioaccumulation in 15 Commonly Consumed Fishes from the Lower Meghna River and Adjacent Areas of Bangladesh and Associated Human Health Hazards.

The lower Meghna River, the easternmost part of the Ganges Delta, faces severe anthropogenic perturbations as it receives a huge discharge and industrial effluents. To measure the metal concentrations and human health hazards, edible tissues of 15 commercially important fish species were collected from the local fish markets and the lower Meghna River, Bangladesh. Trace and heavy metals such as Pb, Cr, Cu, Zn, Mn, Fe, Hg, Ni, Ca, Co, Se, Rb, Sr, and As were detected using the Energy Dispersive X-ray Fluorescence (EDXRF) method. The hierarchy of mean metal concentrations obtained was: Fe (162.198 mg/kg) > Zn (113.326 mg/kg) > Ca (87.828 mg/kg) > Sr (75.139 mg/kg) > Cu (36.438 mg/kg) > Se (9.087 mg/kg) > Cr (7.336 mg/kg) > Mn (6.637 mg/kg) > Co (3.474 mg/kg) > Rb (1.912 mg/kg) > Hg (1.657 mg/kg) > Ni (1.467 mg/kg) > Pb (0.521 mg/kg) > As (BDL). Based on the metal concentration obtained, the carnivorous species contained more metals than omnivores and herbivores. Similarly, the euryhaline and benthic feeder fishes had more metals than the stenohalines and demersal fishes. The metal pollution index (MPI) suggested that the highly consumed fish species Tilapia (Oreochromis mossambicus) and Rui (Labeo rohita) accumulated higher metals than other fishes. Both the Targeted Hazard Quotient (THQ) and Hazard Index (HI) values for adult and child consumers were <1, indicating that consumers would not experience the non-carcinogenic health effects. Although children were more susceptible than adults, carcinogenic risk (CR) exposure of Cr for all the consumers was found in the acceptable range (10−6 to 10−4), but the CR exposure of Pb was negligible for all the consumers. The correlation, principal component analysis (PCA), and cluster analysis were conducted to identify the sources of metals identified from the fish tissue. The results indicated that the probable sources of the pollutants were anthropogenic, arising from agricultural activities, electroplating materials, and lubricants used near the study area. However, the present study showed a different metal concentration in the samples at different levels but within the threshold levels non-carcinogenic and carcinogenic health risks; hence, the fishes of the area, in general, are safe for human consumption.

Impact and Health Risk Assessment of Heavy metals on Contaminated Tomatoes (Lycopersicum esculentum) Consumed in Gombe Metropolis

Tomatoes consumed in Gombe are contaminated with traces and heavy metals due to accumulation of these metals in soil that absorbed by crop plants, which is the most serious environmental problem with significant implications on human health. This study focused on the comparative studies on concentrations of carcinogenic and non- carcinogenic heavy metals analyzed based on WHO Permissible limits. Sample T1 Tomatoes showed mean concentrations in decreasing order of Zn = 0.094 ± 0.045 mg/kg followed by Mn = 0.0744 ± 0.0031 mg/kg then Ni = 0.0394 ± 0.0014 mg/kg, Fe = 0.0163 ± 0.00113 mg/kg, Cd = 0.0063 ± 0.00106 mg/kg, Pb = 0.0031 ± 0.0062 mg/kg, Co = 0.00152 ± 0.00126 mg/kg, As = 0 respectively. Sample T2 showed mean concentrations of heavy metals with the highest of Ni = 0.2095 ± 0.27 mg/kg followed by Zn = 0.1761 ± 0.134 mg/kg, Mn = 0.0487 ± 0.0023 mg/kg, Fe = 0.0233 ± 0.00195 mg/kg, Cd = 0.0147 ± mg/kg, Pb = 0.0047 ± 0.0062 mg/kg, Co = 0.0075 ± 0.0065 mg/kg respectively with few above WHO limits of 0.002 – 0.005mg/kg. Sample T3 Tomatoes showed mean concentrations with highest in decreasing order of Mn = 0.0829 ± 0.017 mg/kg followed by Ni = 0.0809 ± 0.00412 mg/kg, Zn = 0.0504 ± 0.0031 mg/kg, Co = 0.0225 ±0.00080 mg/kg, Cd = 0.0179 ± 0.00243 mg/kg, Fe = 0.0143 ± 0.00057 mg/kg. As = 0.0011 ± 0.000265 mg/kg, Pb = 0.0004 ± 0.000058 mg/kg respectively. Hazard Index (HI) of non-carcinogenic Heavy metals analyzed in Tomatoes samples showed highest hazard index in all the three pathways with Co = 3.64 E+ 00 followed by Pb = 2.71E+00 then Cd = 5.51E-01, Ni = 1.07E-02, Mn = 6.81E-03, As = 2.16E-03, Zn = 7.79E-04, while the lowest Hazard index was shown by Fe = 5.62E-05 indicating HI &gt; 1 with adverse health risk in decreasing order of Co &gt; Pb &gt; Cd &gt; Ni &gt; Mn &gt; As &gt; Zn &gt; Fe respectively. Cancer risk effects of carcinogenic heavy metals investigated through ingestion showed the highest cancer risk of Cd = 4.10E-05 followed by As = 3.23E-07 then Pb = 7.14E-06 with order of Cd &gt; As &gt; Pb &gt; Co while cancer risk through inhalation showed the highest in Co = 1.27E-11 followed by Cd = 7.06E-12 then As = 4.76E-13, the lowest of Pb = 4.41E-14 with order of Co &gt; Cd &gt; As &gt; Pb indicating that some heavy metals contaminated the tomatoes analyzed were projecting while hazard and cancer risk on human health will persisted on body systems at certain prolong time, examining of these heavy metals levels will safeguard public health.

Risk Assessment of Heavy Metals and Soil Qualities from Different Motor Parks Around Ekiosa Market in Benin City, Nigeria

Soil samples from five motor parks around Ekiosa market in Benin City, Edo State were assessed for physicochemical, microbiological qualities, pollution and health risks due to heavy metals exposure. Standard analytical procedures; Atomic Absorbance Spectrophotometry, pour plate method were utilized in the determination of the physicochemical, heavy metals and heterotrophic microbial flora of the top soils. The pH range from 7.28 ± 5.14 to 7.48 ± 5.14; electrical conductivity (µS/cm) of 138.15 ± 97.69 to 234 ± 165.46. The particle size results were 95.83 ± 67.76 to 98.33 ±69.53 % (sand), 1.09±0.77 to 4.40±3.11 % (silt) and 0.002 to 0.9±0.26% (clay). The mean concentrations of metals recorded were found to be in the range (mg/g) of 0.025 to 1.05; 0.035 to 1.06; 0.05 to 0.15 and 24.05 to 31.10 for lead, cadmium, chromium and iron respectively, which are higher than world soil average abundance of metals except for iron which was lower. Total heterotrophic bacterial and fungal enumeration yielded values that ranged from 0.8 to 1.9 x (105 cfu/g) and 0.3 to 2.7 x (105 cfu/g) respectively, which were lower than the control soil (2.3 x 105 cfu/g and 2.7 x 105 cfu/g) for THB and THF respectively. The pollution assessment indices results indicated low ecological risk and moderate contamination for all metals except cadmium, which showed high ecological risk. Pollution assessment indices results indicated a polluted soil, the current safety of this site would be jeopardized over time due to continuous vehicular activities, therefore it should be suggested that motor parks be kept away from market environment.

Effect of trace metal contamination in sediments on the bioaccumulation of bivalve Meretrix meretrix

A quinquennial seasonal study (2015–2019) has been conducted to evaluate the bioaccumulation pattern of trace metals in Meretrix meretrix. The concentration of trace metals in the clam was observed as Cr > Cu > Ni > Zn > Pb > Cd > Hg, (Body> Mantle > Gills), similar to sediments. Contamination Factor of Cu and Cr in sediments showed strong association with the corresponding metal concentration in the body (r = 0.687, r = 0.962), mantle (r = 0.880, r = 0.956) and gills (r = 0.937, r = 0.863). Bioconcentration Factor was high for Cr followed by Ni. Mean Metal Concentration Rate (MMCR) of Cr was high and Hg was low (Body>Mantle>Gills). Our study establishes that the trace metal intake by Meretrix meretrix is associated with seasonal variation, physicochemical factors, sediment texture, chemical speciation and the metabolic stress created within the species induced from increased demand for protein synthesis. The latter resulted in the augmented rate of accumulation of Cu and Cr.

The Bioaccumulation and Health Risk Assessment of Metals among Two Most Consumed Species of Angling Fish (Cyprinus carpio and Pseudohemiculter dispar) in Liuzhou (China): Winter Should Be Treated as a Suitable Season for Fish Angling.

Wild fish caught by anglers were validated to be commonly polluted by metals, but their contamination status could be varied with changing seasons. To determine the seasonal variation in metal pollution and health risks in these fish, this study took Liuzhou City as an example to investigate the concentrations of eight metals in two dominant angling fishes (Cyprinus carpio and Pseudohemiculter dispar) collected, respectively, in winter and summer. The obtained results suggested the mean concentrations of metals in fish are overall lower in winter. Only Cr, Zn, and Cd in some fish were beyond the thresholds in summer. The significant correlations between fish length and weight and most metals suggested the biological dilution effect could exert its influence in winter. The similar distribution of metals in winter suggested that metal bioaccumulation should be manipulated by living habitats, while the inconsistent distribution of metals in summer may be related to the variation in feeding behavior. The metal pollution index (Pi) values were all below 0.2 in winter, which suggested no metal contamination in fish, but most fish were found to be mostly contaminated by Cr and Cd in summer, which was confirmed by their Pi > 0.2. The fish could be consumed freely in winter due to the total target hazard quotient (TTHQ) below 1, while the consumption of fish was not entirely safe in summer, particularly for children, due to TTHQ values that were generally beyond 1. Given the higher weekly recommended consumption of fish in winter, winter should be treated as a suitable season for fish angling.

Are we at risk because of road dust? An ecological and health risk assessment of heavy metals in a rapid growing city in South India

Here, we focus on the concentration of six heavy metals (Cd, Cr, Cu, Fe, Pb, and Zn) in the road dust collected from Tiruchirappalli city, one of the cleanest Tier II cities in South India. Five metals were detected in the road dust, except for Cd that was below measurable limit in all 22 dust samples (15 from the urban city and 7 from the sub-urban city). The mean metal concentration in the road dust collected in Tiruchirappalli city was in the order: Fe (506.39 μg/g) > Zn (47.08 μg/g) > Cu (11.84 μg/g) > Cr (11.47 μg/g) > Pb (0.24 μg/g). The metal levels were higher in outer city compared with inner city due to the increased industrial activities on the outskirts of the city and the reduced cleaning routine. Using principal component analysis (PCA) and hierarchical cluster analysis (HCA), the metal sources were found to be a mix of both natural and anthropogenic activities. Various pollution valuation indices viz., geoaccumulation index, pollution load index, contamination degree, potential ecological risk, health hazard quotient, and carcinogenic risk (2.5 x 10-7), revealed that Tiruchirappalli city falls in the unpolluted category. Also, an increasing trend in the metal pollution is observed in the industrial zones due to the heavy traffic and metal processing activities in the region. For now, the status of metal pollution in Tiruchirappalli is safe, but continuous monitoring is crucial to sustain the unpolluted status.

Concentration, Distribution, and Potential Sources of Heavy Metals in Households Dust in Al-Fallujah, Iraq

Household dust pollution with heavy metals attracted the attention of researchers and environmental managers due to the risk of the health of these metals. The study aims are to determine heavy metals concentrations (Cd, Cr, Cu, Ni, Pb, Zn), their spatial distribution, and their potential sources in the household dust of Al-Fallujah City, Iraq. The dust was sampled from 50 houses. The heavy metals levels in the dust were measured using the atomic absorption spectrophotometry method. The mean concentration of heavy metal was ordered as following: Zn (292.85 mg/kg) &gt; Cr (289.45 mg/kg) &gt; Ni (105.72 mg/kg) &gt; Pb (75.57 mg/kg) &gt; Cu (65.03 mg/kg) &gt; Cd (14.77 mg/kg). The mean concentration of these metals exceeded the reference values. The areal distribution of the reported heavy metals showed specific and non-specific patterns indicating point and non-point pollution sources. The heavy metals potential sources in house dust in the study area were characterized using correlation, Principle components and cluster analyses. The potential sources for Cd, Cu and Pb were interior and exterior sources, while the Ni and Cr were derived from internal sources. This study provides the environmental protection managers and decision-makers with important information about heavy metals concentrations and their sources in indoor environments.

Heavy metal profile in smoked Atlantic cutlass fish (Trichiurus lepturus, linnaeus 1758) from some major markets in Benin metropolis, Nigeria

The concentrations of heavy metals (Pb, Cd, Cu and Zn), in smoked Trichiurus lepturus (Trichiuridae) from some major Markets in Benin Metropolis, Nigeria, were determined employing Atomic Absorption Spectrophotometric technique, in order to ascertain their suitability for human consumption against the dearth of data regarding the metal content of such fish. The mean concentrations of metals in fish ranged from 0.118 mg/kg for Cd to 72.738 mg/kg for Zn. The mean concentration of Zn in fish ranged from 51.80 mg/kg at New Benin Market to 89.28 mg/kg at Ramat Market while the mean concentration of Cu ranged from 6.58 mg/kg at Oba Market to 9.29 mg/kg at Ramat Market. The mean concentration of Cd ranged from below detection limits at Oba and New Benin Markets to 0.31 mg/kg at Ramat Market while the mean the mean concentration of Pb ranged from 0.39 mg/kg at New Benin Market to 0.75 mg/kg at Uselu Market. There was no significant difference (P&gt;0.05) in the mean concentrations of metals in fish between Markets. The toxicity quotient for heavy metals ranged from 0.271 for Cu to 2.425 for Zn. The mean concentrations of Zn, Cd and Pb in fish exceeded the Food and Agriculture Organization and Commission Regulation maximum limits for heavy metals in fish indicating that fish must be consumed with caution, to avert heavy metal poisoning.

Assessment of significant metals in effluents, soil, and pond water of tanneries south of capital of Sudan state

In the present study, impact of tannery effluents and their subsequent on accumulation of some metals (Ca, K, Na, Mg, Cl, S, Cr, Fe, Mn, Pb, and Zn) in water and soil samples in and around South Khartoum industrial area, Khartoum-Sudan were studied. Concentration of metals in tannery effluents (SA), adjacent contaminated pond water (SB), Soil (SC), and uncontaminated water (SD) were assessed by atomic absorption photometer. The results showed high levels of Ca, K, Na, Mg, Cl, S, Cr, Fe, Mn, Pb, and Zn within the water from all sampling point (SA, SB and SC). The investigation exhibited that tanneries wastewater has high mean concentrations of Cr, Fe, Mn, and Pb in all sampling point of effluent, pond water, soil, and uncontaminated water, except Zn which is high only in soil sampling point (SC). The significant metals accumulation displayed a pattern of mean concentration as follow: Soil &gt; Effluent &gt;contaminated pond water &gt; Un contaminated water. Significant metals toxicity levels within the totally different sampling points were compared with water from WHO. Mean metal concentrations in un contaminated water were among the allowable limit set by WHO except for Magnesium (Mg). The comparison indicated that soil (SC) within the neighboring industrial area accumulated metals, enhanced levels of toxic of metals such as Cr, Ni, Zn and Pb, which also demonstrated higher concentration levels in the adjacent contaminated pond water samples. increased levels of poisonous, that additionally incontestable higher concentration levels within the contaminated pond water.

Human Activity in Antarctica: Effects on Metallic Trace Elements (MTEs) in Plants and Soils.

Colobanthus quitensis (Kunt) is one of the two vascular plant species present in Antarctica and develops under severe environmental conditions, being found in both pristine and human-threatened environments. We determined the Cd, Cr, Cu, Mn, Ni, Pb, and Zn levels in C. quitensis roots, leaves, and soils of origin using flame atomic absorption spectroscopy. In January 2017, we collected samples from four geographical zones on the longitudinal gradient along which C. quitensis is distributed, starting from Punta Arenas (PAR) at the extreme south of mainland Chile and moving southwards to the Antarctic territory from King George Island (KGI) to Hannah Point Peninsula (PHA) and finally Lagotellerie Island (LAT). We used certified reference material to validate the plant tissues and soil samples we collected. The highest concentrations of metals that we measured in the soils and in the C. quitensis roots and leaves were in samples we collected at the KGI station, the zone with the greatest human activity. The lowest concentrations we measured were at the LAT station, an island with little human intervention and scarce fauna. The mean concentrations of metals in the roots and leaves of C. quitensis followed a similar order at all sampling locations: Mn > Zn > Cu > Ni > Pb > Cr > Cd. In contrast, in soil, they followed the following order: Mn > Zn > Cu > Cr > Pb > Ni > Cd. The concentration levels obtained for the different metals in the soil and plants tissue samples in this region of Antarctica indicated that the area was non-polluted. However, the metallic trace element (MTE) concentrations may be at an early stage of contamination, as described in other areas of the Antarctic, being a new threat to this continent.

Depth-related dynamics of physicochemical characteristics and heavy metal accumulation in mangrove sediment and plant: Acanthus ilicifolius as a potential phytoextractor

The focus of this study was to determine the depth-wise variability of physicochemical properties (i.e., pH, TOC, TN, and EC), and heavy metals (i.e., Pb, Cu, Zn, As, and Cr) concentration, and the associated biological and ecological risks of the mangrove sediment. The accumulation of metal contents and the phytoremediation and phytoextraction were also investigated in a mangrove species, Acanthus ilicifolius. The mangrove sediment consists of a higher proportion of sand fraction (56.6–74.7%) followed by clay (10–28%) and silt (10.1–15. 7%) fractions. The concentrations (mg/kg) of Pb, Cu, Zn, As, and Cr were ranged from 22.05–34.3, 8.58–22.77, 85.07–114, 5.56–12.91, and 0.98–5.12 in all the sediment layers. The hierarchy of the mean metal concentration in sediment was Zn (102 mg/kg) > Pb (25.6 mg/kg) > Cu (14.8 mg/kg) > As (8.79 mg/kg) > Cr (2.74 mg/kg) respectively. The examined metal concentrations were below the respective average shale values (ASVs). The degree of environmental, ecological, and biological risks was minimal according to various pollution indices like geoaccumulation index (Igeo), contamination factor (CF), and pollution load index (PLI). According to sediment quality guidelines (SQGs), the adverse biological risk effect was not likely to occur. The result of the potential ecological risk index (PERI) demonstrated that the study area was in the low-risk condition as the corresponded RI value < 100. A combined influence of geogenic and anthropogenic factors was identified as the metal sources by multivariate analysis. The study found that the accumulation rate of the metal contents was higher in leaves than that of roots. The mean descending metal concentration values were Zn (107) > Pb (28. 7) > Cu (16.9) > As (11.2) > Cr (4.99) in leaves and Zn (104.32) > Pb (27.02) > Cu (15.29) > As (10.39) > Cr (3.80) in roots. The translocation and bioaccumulation factors of heavy metals suggested that the mangrove plant species, A. ilicifolius can be used for phytoremediation and phytoextraction since the bio-concentration factor and translocation factor > 1. The studied species exhibited the metal tolerance associated with two following strategies, metal exclusion, and metal accumulation. However, excess metal tolerance can impact the surrounding marine environment.

Macroalgae in biomonitoring of metal pollution in the Bay of Bengal coastal waters of Cox\u2019s Bazar and surrounding areas

Although coastal water marine algae have been popularly used by others as indicators of heavy metal pollution, data within the Bay of Bengal for the estuarine Cox’s Bazar region and Saint Martin’s Island has remained scarce. Using marine algae, the study herein forms an effort in biomonitoring of metal contamination in the aforementioned Bangladesh areas. A total of 10 seaweed species were collected, including edible varieties, analyzed for metal levels through the use of the technique of EDXRF. From greatest to least, measured mean metal concentrations in descending order have been found to be K > Fe > Zr > Br > Sr > Zn > Mn > Rb > Cu > As > Pb > Cr > Co. Potential toxic heavy metals such as Pb, As, and Cr appear at lower concentration values compared to that found for essential mineral elements. However, the presence of Pb in Sargassum oligocystum species has been observed to exceed the maximum international guidance level. Given that some of the algae species are cultivated for human consumption, the non-carcinogenic and carcinogenic indices were calculated, shown to be slightly lower than the maxima recommended by the international organizations. Overall, the present results are consistent with literature data suggesting that heavy metal macroalgae biomonitoring may be species-specific. To the best of our knowledge, this study represents the first comprehensive macroalgae biomonitoring study of metal contamination from the coastal waters of Cox’s Bazar and beyond.