Mean Concentrations Of Metals Research Articles

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.

Levels of selected metals in the fruits of a wild edible plant (Rubus steudneri Schweinf) and its underlying soil

ABSTRACT. This study was focused on investigation of amount of macro and trace metals present in the fruit samples of Rubus steudneri Schweinf plant and its underlying soil samples collected from Chencha, Dega Damot and Fiche areas of Ethiopia. The levels of selected metals (K, Ca, Mg, Fe, Mn, Zn, Cu, Cd, and Pb) were determined by microwave plasma-atomic emission spectroscopy using wet-digestion technique. The validity of the method was checked by the analysis of spiked samples whose recovery was found in the range of 90.5-108%. The mean concentration of metals K, Mg, Fe, Ca, Zn, Cu, Mn, Pb and Cd in the fruit samples were found in the range of 9463-9836, 973-1099, 328-639, 2663-2999, 29.6-52.8, 6.70-8.87, 128-639, 2.54-3.37 and 0.26-1.21 mg/kg, respectively. The level of metals in the soil samples were found in the range of 1375-1790, 1169-1388, 74951-104145, 2079-3502, 122-149, 21.6-40.4, 1359-1931, 7.11-17.0 and ND mg/kg, respectively. The accumulation factor values for the tested metals were found in the range of 0.003 (Fe) - 7.07 (K). The Rubus steudneri Schweinf fruit is good source of essential metals and useful to human health. However, the concentration of toxic metals viz. Cd and Pb were found in amount excess as compared to WHO/FAO maximum permissible limit.&#x0D; &#x0D; KEY WORDS: Rubus steudneri Schweinf, Wild edible plant, Fruit, Heavy metals, Soil, Ethiopia&#x0D; &#x0D; Bull. Chem. Soc. Ethiop. 2021, 35(2), 217-228.&#x0D; DOI: https://dx.doi.org/10.4314/bcse.v35i2.1

Evaluation of Health Risk Index of Heavy Metals of Lead, Nickel, Zinc, Iron and Copper in Liza Klunzingeri Muscle in Hormozgan Province

This study was performed to measure the amounts of heavy metals lead, nickel, zinc, iron and copper in garish fish of islands (Qeshm, Hengam and Hormoz) in Hormozgan province. A total of 180 samples were collected in the study areas during the two seasons of summer and winter in 1398. After bioassay, the concentration of elements in muscle tissue was measured using an atomic absorption spectrometer.The results showed that the highest mean concentrations of metals lead, nickel, zinc and copper in Qeshm (lead: 0.082 ± 0.009, nickel: 0.646 ± 0.07, zinc: 31.97 ± 1.33 and copper : 0.881 ± 0.03 μg / g) and iron metal in Hormoz (iron: 19.30 ± 0.75 μg / kg) and the lowest average concentration of metals in Hengam (lead: 0.036 ± 0.007 Nickel: 0.348 ± 0.05, Zinc: 15.13 ± 1.06, Copper: 0.657 ± 0.03 and Iron: 12.13 ± 0.4 μg / gram. The results also showed that there is a direct relationship between metal concentration and length and total body weight of fish. On the other hand, the concentrations of lead, nickel, zinc and copper in barley fish samples in the study areas were lower than the international standards of FAO, WHO, FDA, NHMRC and UKMAFF. Also, the level of potential risk and risk index for non-cancerous diseases in adults and children in the aquifer muscle tissue was less than 1. Therefore, it can be concluded that there are currently no problems for human health in terms of consumption of this fish.

Assessment of heavy metal contaminations in water and sediment of River Godavari, India

Abstract The Godavari is the largest river of peninsular India and receives a significant quantity of pollutants from diverse sources, including many industries, urban developments and agricultural fields. Such pollution is more prominent in the upper stretch of the river. This work aimed to assess the water and sediment contaminations of River Godavari for the presence of trace metals Cd, Cr, Cu, Mn, Pb and Zn. Samples were collected from 10 sampling stations covering the entire stretch of the river. Sediment pollution characteristics and potential ecological risks were evaluated by calculating contamination factor, degree of contamination, pollution load index, geo-accumulation, and the potential ecological risk index. Pearson's correlation analysis and principal component analysis were used to predict the probable sources of heavy metals. The concentrations of studied heavy metals in water were mostly observed below the detection limit using the flame mode of an Atomic Absorption Spectroscope and recorded safe for the biotic community. The mean concentrations of metals in the sediments were calculated and also recorded to be safe with respect to the guideline values of the United States Environmental Protection Agency (USEPA, 1999). However, the sampling site-specific calculated contamination factors indicated moderate contamination of some of the stretches as: S1 for the presence of Cu, Mn, Zn; S2 for Cu, Zn; S3 and S4 for Cu; S5 for the dominance of Mn. The rest of the sites were free from sediment metal contaminations. The degree of contamination values specified S2 as moderately contaminated. Pollution load index indicated sites S1 and S2 as contaminated. Both geo-accumulation and potential ecological risk index designated lower levels of pollution in the river owing to sediment metal contaminations. Furthermore, a comparison of the heavy metal concentrations with sediment quality guidelines signified that the heavy metal pollutions (Cu, Cr, Mn and Zn) tend to pose occasional harmful effects on the ecosystem. From Pearson's correlation analysis and principal component analysis, two main sources of metal pollution were predicted. The Cu, Cr and Zn contaminants were mainly derived from human activities and Mn from natural sources as well as human activities.

Seasonal Dynamics of Heavy Metal Concentrations in Water, Fish and Sediments from Haor Region of Bangladesh

Heavy metal concentrations in water, fish, and sediments from Bangladesh's haor region were investigated. Fish and sediment samples were taken once a season and evaluated using standard methods, while water samples were collected monthly. Results showed that metals in water (mg/L) were found in order of Mn (0.1694) > Cu (0.0189) > Zn (0.0045) > Pb (0.0040) > Cd (0.0028) within the maximum permissible level of Environment Conservation Rules (ECR). Mean concentrations of metal in fish (mg/kg–dry wt.) found in order of Zn (56.16) > Cu (25.47) > Mn (4.36) > Pb (2.19) > Cd (1.27) that were higher than maximum allowable level of Food and Agricultural Organization (FAO) except Cu. Metal in sediments (mg/kg) found in order of Mn (127.61) > Zn (32.51) > Pb (10.09) > Cu (5.40) > Cd (0.43), and except Cu all metal concentrations were lower than the Environmental Protection Agency's (EPA) probable effect concentrations. In water and sediments, pollution indices revealed a critical pollution threshold for water, and a range of unpolluted to highly polluted for sediments. Sampling sites had low potential ecological risk, despite the fact that metals were showing signs of a negative impact on people' health. Furthermore, bio-concentration factor for fish and water was low to extremely high, but for fish and sediment was low. The level of heavy metal contamination in haor shows the situation is alarming for biota and residents of the region. The relevant authority should control and monitor the aquatic ecology in order to protect it.

Association of Sulfur, Transition Metals, and the Oxidative Potential of Outdoor with Acute Cardiovascular Events: A Case-Crossover Study of Canadian Adults.

Background:We do not currently understand how spatiotemporal variations in the composition of fine particulate air pollution [fine particulate matter with aerodynamic diameter ()] affects population health risks. However, recent evidence suggests that joint concentrations of transition metals and sulfate may influence the oxidative potential (OP) of and associated health impacts.Objectives:The purpose of the study was to evaluate how combinations of transition metals/OP and sulfur content in outdoor influence associations with acute cardiovascular events.Methods:We conducted a national case-crossover study of outdoor and acute cardiovascular events in Canada between 2016 and 2017 (93,344 adult cases). Monthly mean transition metal and sulfur (S) concentrations in were determined prospectively along with estimates of OP using acellular assays for glutathione (), ascorbate (), and dithiothreitol depletion (). Conditional logistic regression models were used to estimate odds ratios (OR) [95% confidence intervals (CI)] for across strata of transition metals/OP and sulfur.Results:Among men, the magnitudes of observed associations were strongest when both transition metal and sulfur content were elevated. For example, an OR of 1.078 (95% CI: 1.049, 1.108) (per ) was observed for cardiovascular events in men when both copper and S were above the median, whereas a weaker association was observed when both elements were below median values (, 95% CI: 1.007, 1.031). A similar pattern was observed for OP metrics. was not associated with acute cardiovascular events in women.Discussion:The combined transition metal and sulfur content of outdoor influences the strength of association with acute cardiovascular events in men. Regions with elevated concentrations of both sulfur and transition metals in should be examined as priority areas for regulatory interventions. https://doi.org/10.1289/EHP9449

Occurrence and distribution of heavy metals in the tissues of Physa acuta (D.) in relation to the contamination level of sediments from Boumerzoug wadi (Algeria)

The aim of this study was to assess the metallic contamination of sediments, and metals bioaccessibility via their distribution in the gastropod Physa acuta (Pulmonata). The concentrations of Cd, Co, Cr, Cu, Mn, Ni, Pb and Zn in the soft tissue and shell of P. acuta, as well as in fresh surface sediments from the Boumerzoug wadi and its tributaries, northeastern Algeria, were determined by flame atomic absorption spectrophotometry. The samples were collected from ten sites on five occasions (May, September and December 2016, March and July 2017). Results showed that the trace metal mean concentrations in sediments, tissues and shells of the gasteropod, followed a decreasing order: Mn > Zn > Cr > Cu > Ni > Pb > Co > Cd. The pseudo-total contents of Cd, Co, Cr, Cu, Mn, Ni, Pb, and Zn in sediment were about 0.45 ± 0.43, 12.19 ± 2.49, 51.70 ± 19.82, 46.70 ± 39.60, 296.15 ± 105.83, 36.50 ± 10.93, 32.40 ± 9.10, and 186.72 ± 118.93 mg/kg dw, respectively. The concentrations of the metals studied in P. acuta were age dependent, with adults having significantly higher concentrations than juveniles. All heavy metal concentrations detected were higher in soft tissue with the lowest coefficient of variation than in shells for both adults and juveniles. The presence of a significant direct relationship between the Cd content in the sediment and in the soft tissues of P. acuta in both adults (r = 0.83; P < 0.01) and juveniles (r = 0.53; P < 0.01), and the high bioaccumulation factor observed make this gastropod a good indicator for the monitoring of freshwater sediment contamination by this metal.

Physicochemical Characteristics and Heavy Metals Contents in Soils and Cassava Plants from Farmlands within Nnamdi Azikiwe University, Awka, Anambra State

Soil samples and cassava tubers collected from farmlands within Nnamdi Azikiwe University, Awka vicinity were analyzed for their heavy metal levels using Atomic Absorption Spectrophotometer (AAS) in order to assess their levels of contamination on the environment as a result of excessive fertilizers and automobile emission. Physiochemical properties of the soil samples were determined using standard methods. The soil pH had a mean value of 6.27 ± 0.07, 6.10 ± 0.06 and 6.57 ± 0.03 respectively indicating that the soils were slightly acidic to neutrality. Total organic carbon and nitrate mean values were 105.20 ± 6.20, 95.75 ± 9.57 and 94.6 ± 2.27 and 138.07 ± 12.09, 149.35 ± 14.25 and 149.20 ± 1.17 respectively showing presence of some organic matters. The mean levels of heavy metals in the soil samples were 0.01 ± 0.01, 0.05 ± 0.03 and 0.05 ± 0.03 for lead (Pb), 0.24 ± 0.16, 0.001 ± 0.001 and 0.001 ± 0.000 for cadmium (Cd) and 0.00 ± 0.00, 0.010 ± 0.006 and 0.001 ± 0.001 for chromium (Cr). These metals levels were in the abundance trend of Pb&gt;Cd&gt; Cr. The mean metal concentrations obtained in the cassava tubers respectively were 0.001 ± 0.001, 0.001 ± 0.001 and 0.005 ± 0.005 for lead (Pb), 0.000 ± 0.000, 0.0003 ± 0.0003 and 0.000 ± 0.000 for cadmium (Cd) and 0.002 ± 0.002, 0.000 ± 0.000 and 0.002 ± 0.002 for chromium (Cr). These metals levels were in the abundance trend of Pb&gt; Cr &gt; Cd. For both the soil and cassava samples, there were no significant variations in the heavy metal concentrations and also in physicochemical parameter except for pH; this showed that there is low heavy metal enrichment in the soils studied. Based on the study, the following heavy metals (Pb, Cd, and Cr) falls within the Codex maximum permissible limits 0.1mg/l or ppm expect soil cadmium in science village which is above the Codex limit. The overall results showed that the farmlands (on soils and cassava tuber) appear to be free from poisoning or some metal enrichment and safe for agricultural purposes and also safe for human health and consumption.

Metals concentration levels in printed circuit boards of discarded cathode ray tube television: trends over the years

ABSTRACT The main objective of this study was to investigate the trends of Cu, Pb, Ni, Cr and Cd concentrations present in printed circuit boards of cathode ray televisions over the years. Dismantling, shredding, pulverisation, digestion and chemical analysis were followed for sorting, separation, and analysis of metal concentrations in printed circuit boards of cathode ray televisions. After digestion using EPA SW 846 method 3050B, the extracts were analysed for metal concentrations using atomic absorption spectrophotometric technique. The results obtained showed that the mean metal concentrations in all televisions’ printed circuit boards studied were – Cu: 11.73 ± 2.91%, Pb: 3.30 ± 0.86%, Ni: 0.106 ± 0.138%, Cr: 0.00523 ± 0.00130% and Cd: 0.00291 ± 0.00148%. There was virtually no regular pattern in the average metal levels from 1975 to 1999; they initially decreased, increased and then decreased. However, an observable decrease in the level of these metals was noticed from 2000 to 2009. Cu, Pb, Ni, Cr and Cd were noticed to have decreased from 2000–2004 to 2004–2009.

Risk Assessment of Heavy Metals in Basmati Rice: Implications for Public Health

Basmati rice is increasingly recognized and consumed in different parts of the world due to its different tastes and nutritional properties. This research focused on determining the cadmium (Cd), cobalt (Co), Copper (Cu), iron (Fe), manganese (Mn), nickel (Ni) and zinc (Zn) content in locally grown basmati rice in Pakistan and assessing the risks of these values to human health. Root, shoot and grain samples of basmati rice were taken, along with soil samples from the five regions studied. Metal mean concentrations (mg/kg) in grains fluctuated from 2.70 to 9.80 for Cd, 4.80 to 9.85 for Zn, 1.16 to 1.46 for Cu, 1.84 to 10.86 for Co, 2.05 to 13.07 for Fe, 5.03 to 11.11 for Mn and 3.24 to 13.28 for Ni, respectively. All metal values were within permissible limits except for Cd. The enrichment factor for Cd was highest among all sites. Cobalt and zinc had the highest bioaccumulation factor and translocation factor. The highest enrichment factor was noticed for Cd and the lowest for Cu. The health risk index at all examined sites was less than one. Consistent examination is recommended to limit health hazards instigated by the use of rice polluted with a greater concentration of Cd.

Concentrations and health risks of heavy metals in five major marketed marine bivalves from three coastal cities in Guangxi, China

Seafood consumption provides essential elements to humans while also posing risks to human health. A total of 2610 individuals of five edible marine bivalve species (Ruditapes philippinarum, Paphia undulata, Meretrix meretrix, Sinonovacula constricta and Meretrix lyrata) were randomly sampled from six farmer markets in three cities (Beihai, Qinzhou and Fangchenggang) in the southernmost coastal region of China. The concentrations of heavy metals (Cu, Pb, Zn, Cd, Cr, Hg and As) were determined by inductively coupled plasma mass spectrometry (ICP-MS). The estimated daily intake (EDI), target hazard quotient (THQ), total hazard index (HI), and target cancer risk (TR) were calculated to evaluate potential human health risks from bivalve consumption. The mean concentrations of metals in the tissues of bivalves descended in the order Zn > Cu > As > Cd > Cr >Pb > Hg in descending order, and the concentrations varied substantially among the five bivalves. Heavy metal concentrations in edible tissues of most bivalve samples were below the safety limits set by national and international regulations, and there were significant correlations between certain metal concentrations. The EDI values for each metal in each bivalve were significantly lower than the corresponding PTDI (provisional tolerable daily intake) values. Health risk assessment showed that although there is no noncarcinogenic health risk for local residents exposed to individual or combined metals from these bivalves, there is a carcinogenic risk from Cd and Cr exposure. Thus, in the long term, monitoring and controlling bivalve consumption will be important. Although current accumulation levels of bivalves are safe, continued and excessive lifetime consumption over 70 years may pose a target cancer risk.

Assessment of trace metal contamination by geochemical normalisation in sediments of two lagoons: A comparative study of the Kpeshie and Muni lagoons, Ghana

Heavy metal contamination status of bottom sediments of two lagoons was compared by the employment of Enrichment Factor (EF) analysis for Iron (Fe), Manganese (Mn), Cupper (Cu), Lead (Pb), Chromium (Cr), Nickel (Ni), Silver (Ag), Zinc (Zn) and Mercury (Hg). Kpeshie Lagoon recorded enrichment (EF ≥ 1) for Cd, Pb, Ag, Hg and Zn, whilst Muni Lagoon recorded enrichment for Cd, Mn, Ag, Hg and Zn as metals of anthropogenic influence. Kpeshie, situated in a highly urbanized area, has 75% spatial distribution of Pb enrichment. The assessment shows that Ag and Hg are the most enriched metals in the sediments of both Lagoons, reaching extremely severe levels. Only Mn showed statistically significant difference in mean concentration of metals for both Lagoons. Pearson correlation matrix indicated that Pb had a strong relation with Ag, Hg and Zn (r = 0.956; p &lt; 0.05) which is significant in Kpeshie. It also had a strong association with Ag and Hg but not with Zn (r = 0.240) in the Muni. The study clearly delineates Pb as a pollutant that designates the urban status of Kpeshie. Its associated metals; Ag, Hg and Zn which may be coming from a common source are from industrialized zones.

Characterization of Airborne Particulates and Worker Exposures in Electro-static Powder Coating Operations.

This study was to examine the airborne particulates/dusts and worker exposures in electro-static powder coating operations. Temporal variation and size distribution of dusts were assessed using direct-reading instrument, while the worker task-specific dust exposures (n = 41) were measured in three factories using conventional filter method. Additionally, toxic metal levels in the coating powder (n = 27) were analyzed to assess hazard potentials. Continuous monitoring of airborne respirable dust levels indicated large temporal variation across a normal working day. The particulate levels outside spraying booths were generally low (below 0.10 mg m-3) during normal spraying operation, but short-term level may reach as high as 21.8 mg m-3 (averaged at 4-5 mg m-3) when specific task such as cleaning the pipelines and spraying booth, was performed. Exploratory assessment on particle size distribution at four major working zones, administration, uploading, spraying, and baking, indicated no major difference among the zones, and between factories. The particle count median aerodynamic diameter was 0.88-1.69 µm, while the mean number concentrations were 10.97, 15.17, 18.49, and 27.03 (# cm-3) for zones administration, uploading, spraying, and baking, respectively. The worker task-specific dust exposures were found low during normal spraying, with the mean short-term total and respirable dust concentrations being 0.88 and 0.41 mg m-3, respectively. Both levels increased to 3.48 and 5.19 mg m-3, respectively (P < 0.05), if powder changing and system cleaning were done. Short-term total and respirable dust concentrations were 94.2 and 56.1 mg m-3, respectively, when complete cleaning process was performed inside spraying booth. Both levels exceeded the short-term exposure limits. The mean concentration of metals in the powder samples were 6.78, 9.52, 10 717, 2805, 1020, and 1361 µg g-1 for Pb, Cr (total), Al, Fe, Cu, and Sr, respectively. This study demonstrated that cleaning of spraying booth resulted in high dust exposures well exceeding the exposure limit. Toxic metals, particularly Pb, Cd, and Cr (total), levels measured in the powder samples were found low, and the resulting exposures were below the exposure limits, indicating relative low risks associated with the exposure at current dust levels.

SELECTED HEAVY METAL CONTENT OF ANAMBRA-GROWN OIL PALM BUNCH ASH (NGU): HUMAN HEALTH RISK ASSESSMENT.

Edibles can be contaminated by heavy metals as described in various patents. The study determined the potential human health risk associated with the consumption of palm bunch ash (PBA) from Anambra State, Nigeria. Concentrations of Cd, Pb, Hg and Zn were determined using Atomic Absorption Spectrophotometer (AAS). Human health risk assessment employed Estimated Daily Intake (EDI), Target Hazard Quotient (THQ), Hazard Index (HI), and Carcinogenic Risk. The EDI values (5.14x10-6 – 5.22x10-4, 9.97x10-5 – 1.23x10-3, 4.14x10-7 – 5.91x10-4, 4.29x10- 7 – 1.36x10-2) mg/kg/day and the THQ values were (9.43x10-3 -5.22x10-1, 7.84x10-4 – 0.586, 5.86x10-3 – 3.83, 1.43x10-6 – 3.90x10-1) for Cd, Pb, Hg and Zn respectively. There was a violation of permissible Tolerable Daily Intakes (PTDI) set by JECFA. Hazard indices of some samples were more than 1, another indication of health concern. The mean concentration of metals in PBA ranged from 0.0041 - 95.012mg/kg. When compared with standards by WHO, EU and USEPA, violation was observed in Cd, Pb and Hg. Cadmium showed very high carcinogenic risk with values of 3.18 x10-3mg/kg/day. Consumption of palm ash from Anambra State Nigeria may pose significant health risk.

Assessment of Heavy Metal Contamination in the Soils of the Gulf of Aqaba (Northwestern Saudi Arabia): Integration of Geochemical, Remote Sensing, GIS, and Statistical Data

Ghrefat, H.; Zaman, H.; Batayneh, A.; El Waheidi, M.M.; Qaysi, S.; Al-Taani, A.; Jallouli, C., and Badhris, O., 2021. Assessment of heavy metal contamination in the soils of the Gulf of Aqaba (Northwestern Saudi Arabia): Integration of geochemical, remote sensing, GIS, and statistical data. Journal of Coastal Research, 37(4), 864–872. Coconut Creek (Florida), ISSN 0749-0208.Rock and soil sample geochemical analysis was conducted to investigate the extent and causes of soil contamination in the Gulf of Aqaba region in NW Saudi Arabia. The inductively coupled plasma mass spectrometry was used to determine the concentrations of Pb, Zn, Cu, Co, Cr, Mn, Fe, Hg, Mo, and Cd in 23 soil samples and 25 samples from granitic and Cenozoic marine sedimentary formations. The geochemical results have been integrated with remote sensing, GIS, and statistical analysis to assess the severity of soil pollution in the area. The concentrations of heavy metals (ppm) in the collected soil samples were as follows: Fe (2259.70), Mn (101.85), Zn (20.15), Pb (10.74), Cr (8.67), Cu (6.10), Co (1.35), Mo (0.69), Hg (0.30), and Cd (0.17). A significant variation in the mean metal concentrations was observed for the rock samples. The correlation analysis results showed that different degrees of positive and negative relationships exist among different metals in the area. Two factors (PC1 and PC2) were identified using the principal component analysis (PCA) and were responsible for about 60% of the total variance in the data. The studied metals were separated and classified into two factors based on their geochemical features and source. In contrast, the hierarchical cluster analysis grouped the identified metals into different groups based on the similarity of their characteristics. The principal component (PC2) applied to the Sentinel-2A image classified the land cover in the area into three classes: vegetation, barren rocks, and urban area. The enrichment factor shows a relatively higher percentage of enriched Mo; however, the indices of geo-accumulation and potential ecological risk generally reveal no substantial metallic contamination in the study area. The main sources of soil contamination with metals are rock-weathering processes and various agricultural works that are widely practiced in the area.

Distribution characteristics, chemical speciation and human health risk assessment of metals in surface dust in Shenyang City, China

Surface dust samples were collected in 2018 at 30 different sites in Shenyang City, China. Concentrations of chromium (Cr), arsenic (As), cupper (Cu), lead (Pb), zinc (Zn), nickel (Ni), mercury (Hg) and cadmium (Cd) were determined, and chemical speciation of metals were analyzed. Mean metal concentrations followed the order Zn > Cu > Pb > Cr > Ni > As > Cd > Hg. Although concentrations of metals in dust samples were lower than previously reported, a measurable metal pollution signature in dust still exists. Metals (except for As), are influenced by anthropogenic activities. Spatial variation in mean metal dust concentrations and speciation varied significantly and were influenced by land-use and industrial activities. Source appointment Results revealed that pollution of surface dust was derived from three main source profiles (industrial and traffic pollution, coal combustion, and urban pollution), contributing to 90.7% of the variance. Health risk assessment indicated that risks were low, but children were susceptible to metals in surface dust. Results indicated oral ingestion was the dominant exposure pathway. Non-carcinogenic Cr and Pb and carcinogenic As were the main metal contaminants in surface dust.

Risk assessment of the anthropogenic activities (quarrying) and heavy metal profile in mining environment.

The need to generate internal revenue by most individuals and government in Nigeria has led to the establishment of quarries in different parts of Ebonyi state of Nigeria. This study was aimed at determining the risk associated with the heavy metal burden in the state. Soil samples from the quarrying environments designated as MS1, MS2, and MS3 were analyzed for the metal profile using inductively coupled plasma optical emission spectrometry (ICP-OES). The result showed that the mean concentration of metals which is a representation of the whole sites showed a higher concentration of Ca (40.065 ± 1.011ppm), Mg (12.450 ± 8.815ppm), K (16.631 ± 14.670ppm), and Mn (19.539 ± 3.225ppm) while Na (1.326 ± 0.117ppm) was low. The heavy metal profile showed Pb (0.120 ± 0.027ppm), Fe (27.718 ± 1.523ppm), Zn (2.227 ± 0.570ppm), Cu (6.267 ± 1.402ppm), Ni (1.856 ± 0.472ppm), Mo (1.758 ± 0.258ppm), Cd (0.023 ± 0.006ppm), Cr (0.037 ± 0.011ppm), etc. Hg was found to be below detectable limit while the Cs was not radioactive. The mean values were found to be lower than the permissible limit of each metal. The pollution index (PI) was calculated for the different sites, and the result reveals that MS3 (0.0426) had a higher PI when compared to MS1 (0.0341) and MS2 (0.0317). Therefore, the PI of the sites showed MS3 > MS1 > MS2. These results showed that the environment is still as safe as PI < 1. The geoaccumulation index also showed a safe environment since its values were less than 0 which means that the environment is practically uncontaminated. Other risk determining parameters showed that the three locations were still within a safe level. Although the results of the study have shown a safe environment, it is still necessary to keep close monitoring of the heavy metal profile of the environment, since these metals can bioaccumulate in living tissues with time.

Levels of selected toxic and essential elements in fish and oysters from Western Indian Ocean, Coast of Tanzania

Concentrations of toxic and essential elements in selected finfish and shellfish collected from Dar es Salaam and Tanga, Indian Ocean coast of Tanzania are presented. The elemental concentrations were determined using Energy Dispersive X-ray Fluorescence (EDXRF) spectrometer coupled with X-lab ProTM software. The mean concentrations of metals observed in finfish and shellfish collected from Tanga ranged from 3.40–5.75, 1.8–37.17, 3.5–7.1, 0.6–1.3, 0.53–0.73 and 16.80–96.70 mg kg–1 for As, Cu, Mn, Ni, Pb and Zn, respectively. For Dar es Salaam, the mean concentrations of metals ranged from 3.34–9.46, 2.90–30.53, 3.4–6.9, 0.7–1.0, 0.57–0.80 and 14.2–100.90 mg kg–1 for As, Cu, Mn, Ni, Pb and Zn, respectively. Thumbprint emperor showed the highest levels of Cu and Ni; octopus showed the highest values of As and Pb, while sardines showed the highest level of Mn. Oysters, used as pollution indicators in this study showed the highest elemental concentrations and exceeded their mean levels in finfish from Dar es Salaam by factors of 1.30, 7.15, 6.27, 2.72, 1.29 and 35.57 for As, Cu, Mn, Ni, Pb and Zn, respectively. In samples from Tanga, the metal concentrations in oysters were several times higher (3.76, 17.68, 1.12, 3.89, 1.88 and 66.92 for As, Cu, Mn, Ni, Pb and Zn) than in finfish, respectively. Based on metal concentrations in oysters, it can be concluded that coastal waters are contaminated with heavy metals. However, with an exception of arsenic and copper, the elemental levels in finfish are within the maximum permissible levels recommended by various international standards and guidelines.&#x0D; Keywords: Finfish, toxic elements, essential elements, pollution, EDXRF