Mean Concentrations Of Trace Metals Research Articles

Spatial and Multivariate Statistical Analyses of Human Health Risk Associated with the Consumption of Heavy Metals in Groundwater of Monterrey Metropolitan Area, Mexico

Groundwater is the main source of drinking water supply in most urban environments around the world. The content of potentially toxic elements is increasing in many groundwater systems owing to inadequate groundwater recharge, aquifer overexploitation, natural source release, or various anthropogenic activities that lead to groundwater quality degradation. The ingestion of groundwater contaminated with potentially toxic elements has been reported to have harmful health effects. This study aimed to assess the presence of several potentially toxic elements (Al, As, B, Cr, Cu, Fe, Mn, and Zn) in groundwater of the Monterrey metropolitan area in Northern Mexico and the carcinogenic and noncarcinogenic human health risks associated with exposure. Multivariate statistics and geospatial analysis were applied to identify the causative determinants that modify the groundwater quality along the metropolitan area. Mean concentrations of trace metals remained below drinking water standards and World Health Organization guidelines. The risk of harmful effects on human health due to ingestion of all eight metal(loid)s in groundwater was assessed as 2.52 × 10−2 for adults and 2.16 × 10−2 for children, which can be considered as negligible chronic risk and a very low cancer risk. However, the risks of oral consumption of Cr being carcinogenic to children and adults were 7.9 × 10−3 and 9.2 × 10−4, respectively. As these values exceeded the target risk of 1 × 10−4, it can thus be considered “unacceptable”.

Possible Sources of Trace Metals in Obese Females Living in Informal Settlements near Industrial Sites around Gauteng, South Africa.

Trace metals have been reported in the literature to be associated with obesity. Exposure to some trace metals such as Mn, Cr, Ni, Cd, and Pb may pose a serious health risk to individuals living around a polluted environment. The present study assessed the levels of trace metals in the blood of obese females living around industrial areas in Gauteng, South Africa. The study was carried out using a mixed method approach. Only females with a BMI ≥ 30.0 were considered. A total of 120 obese females participated in the study (site 1: 40-industrial area, site 2: 40-industrial area, and site 3: 40-residential area), aged 18-45 and not in menopause. Blood samples were analysed for trace metals content using inductively coupled plasma mass spectrometry (ICP-MS). The mean concentrations of trace metals were in the order Pb > Mn > Cr > Co > As > Cd (site 1), Pb > Mn > Co > As > Cd (site 2), and Mn > Cr > Co > As > Pb > Cd (site 3). The blood Mn from site 1 ranged from 6.79 µg/L-33.99 µg/L, and the mean differences obtained from the participants from different sites were significant (p < 0.01). The blood levels of Mn, Pb, Cr, Co, As, and Cd were above the recommended limits set by the WHO in some of the participants. The present study noted, among others, closeness to industrial areas, lifestyle decisions such as the use of tobacco products by their partners indoors, and the method used for cooking as factors that might have accounted for the blood levels of Mn, Pb, Cd and Co. The study showed that there is a need for constant monitoring of the levels of trace metals in the blood of those living in these areas.

Records of trace metals since the Holocene in sediments of Laizhou Bay, Bohai Sea, China

Trace metal (Cu, Pb, Zn, Cr, Cd, As, Hg, Ni, Li, and Co) concentration profiles along a sediment core were investigated to obtain background values, assess depositional trends and contamination levels in the Laizhou Bay, China. The enrichment factors of the metals indicated no anthropogenic enrichment, except for Pb, Cd, and Hg, which have been influenced by human activities since 7 ka. The mean concentrations of trace metals in the 10–7 ka phase can be considered as the background values in the study area. Principal component analysis indicated that the metals were mainly naturally sourced throughout the observed depositional period. Their geoaccumulation indices indicated that the sediments were not contaminated by Cu, Zn, Cr, Ni, and Co, but were contaminated by Pb, Cd, and Hg during the 7–0 ka period.

Pollution level of trace metals (As, Pb, Cr and Cd) in the sediment of Rupsha River, Bangladesh: Assessment of ecological and human health risks

The study area was selected in the Rupsha river basin and the sediment samples were collected to determine trace metal concentrations of As, Pb, Cd, and Cr along with biological effects, and potential ecological and human health hazards for adults and children. The concentrations of trace metals were detected from sixty composite sediment samples using an Atomic Absorption Spectrophotometer (AAS) following some sequential analytical procedures. The mean concentrations of trace metals were organized in the descending order of chromium (Cr) (43.2 mg/kg) &amp;gt; lead (Pb) (29.21 mg/kg) &amp;gt; arsenic (As) (5.18 mg/kg) &amp;gt; cadmium (Cd) (1.8 mg/kg). The current study highlighted that metals were attributed to the riverine sediments from natural sources and other anthropogenic sources, particularly from various industries. Based on the effect-range classifications of threshold effect concentration (TEC) and probable effect concentration (PEC), the trace metal concentrations can impact on the sediment-dwelling organisms occasionally especially for Cr, Cd, and Pb. That is, the concentrations had negative biological consequences on aquatic creatures. The assessed potential ecological risk of Cd offers a significant risk to the aquatic ecosystem, whereas As, Cr, and Cd were in low-risk. Most of the sites of the study area were within the range of moderate risk, indicated by the risk index (RI) values. Furthermore, the applied sediment quality indices, geo-accumulation index (Igeo) indicated that sediment was contaminated by Cd whereas contamination factor (CF) denoted that the sediment of the study area was moderately polluted by Pb. However, pollution load index (PLI) revealed that the study area was polluted for cumulative sence especially in winter season. The age-group risk index (HI) was much lower than the threshold limit of 1, showing that the pollution had no non-carcinogenic risk effect. Total carcinogenic risk (TCR) was less than one-tenth of a percentile. For the sake of human and environmental health, proper monitoring of metal element attribution and strict regulation are required to lessen trace metal pollution.

Analysis of Trace Metal Concentration in Rainwater Samples Collected from Spatially Separated Coastal Cities Facing the South China Sea in Northern Sarawak, Borneo

A comparative analysis of trace metal (Cu, Pb, Fe, Mn, Zn, Cd, Ni and Co) concentration and physical parameters (pH, EC, TDS and DO) in rainwater samples collected from two major coastal cities in Malaysian Borneo (Sarawak state) were determined in the present research. Cumulative monthly rainwater samples were collected from the Limbang city and Miri city during October 2016–September 2017. Rainwater collected from the Limbang city shows slightly alkaline nature with a mean pH≥6.07 whereas the rainwater in Miri city is acidic(mean pH = 5.35). Trace metal concentration in rainwater collected from both locations shows slight variation. Mean concentration of trace metals in rainwater samples follows the decreasing order of Fe>Ni>Pb>Mn> Co>Cu>Zn>Cd and Fe>Ni>Pb>Mn>Zn>Co>Cu>Cd in Limbang city and Miri city respectively. Among the trace metals, Fe (1.09 and 0.98 mg/L) and Ni (0.15 and 0.13 mg/L) shows the highest mean concentration in rainwater samples collected from both locations and maximum concentration of trace metals are observed in rainwater samples collected from the Limbang city. Pearson’s correlation test explained the inter-relationship between the parameters whereas the factor analysis confirmed the contributing sources of trace metals (anthropogenic activities such as pollution from vehicles, petrochemical industries, forest biomass burning and dust particles from exposed land area) and its variation in the rainwater samples by showing a total variance of 80.18% with three factor components in the Limbang city and a variance of 93.11% with four factor components in Miri city. High Pb/Zn ratio also indicates the strong influence of anthropogenic activities present in the region. Backward air mass trajectory analysis supports the findings by indicating a contribution from combined marine and crustal sources of air mass trajectories reaching the sampling locations and is heavily controlled by prevailing monsoon characteristics of the region. Overall, it can be concluded that, the major source of trace metals in rainwater in this region is contributed by anthropogenic processes operated in the region.

Spatial distribution, source apportionment, and associated risks of trace metals (As, Pb, Cr, Cd, and Hg) from a subtropical river, Gomti, Bangladesh

Sediment samples from the Gomti River basin were investigated to determine and evaluate trace metal concentrations, their biological effect, and potential ecological and human health risks for adults and children. The mean concentrations of trace metals were organized in the descending order of mercury (Hg) (0.08 mg/kg) > chromium (Cr) (0.06 mg/kg) > lead (Pb) (0.05 mg/kg) > arsenic (As) (0.02 mg/kg) > cadmium (Cd) (0.01 mg/kg). The current study illustrated that metals were attributed to the area from natural sources and different anthropogenic sources especially from industries. However, the concentration levels were lower than the sediment quality guidelines (SQGs) based on the effect-range classifications of threshold effect concentration (TEC) and probable effect concentration (PEC). Therefore, the concentration of the elements showed no adverse biological effects on aquatic organisms. The evaluated potential ecological risk index also revealed the low toxicity to the aquatic environment. Moreover, the applied sediment quality indices, geo-accumulation index (Igeo), contamination factor (CF), and contamination severity index (CSI) suggested that the contamination levels of the elements were in the acceptable range, and the contamination had not notably impacted on the sediment quality. The risk index (HI) concerning age groups was significantly less than the threshold limit of 1 indicating that the contamination had no non-carcinogenic risk effect. The total carcinogenic risk (TCR) was less than a risk value of 1 × 10−4. Hence, the current study suggests that immediate remediation is not required due to an absence of alarming conditions in the study area. Proper monitoring of the attribution of the metal elements should be done for the betterment of human and environmental health.

Seasonal hydrochemical dynamics of surface water in the Limbang River, Northern Borneo—evaluating for spatial and temporal trends

Limbang River Basin (LRB), an equatorial tropical river basin which witnesses the effect of climate change and terrain modification, is hydro-statistically characterized in the present research. In order to characterize the seasonal dynamics of hydrochemical characteristics of surface water, a total of 72 surface water samples were collected from 24 locations in the Limbang River and its tributaries for three different sampling periods (November 2016 (S1), March 2017 (S2), and September 2017 (S3)). Physical parameters (pH, electrical conductivity (EC), total dissolved solids (TDS), dissolved oxygen (DO), turbidity), nutrients (sulfate, nitrate, ammonia, phosphate), major ions (Ca, Mg, Na, K, Cl, HCO3), and trace metals (Co, Ni, Cd, Fe, Mn, Pb, Zn, Cu) were analyzed using standard procedures and the results were statistically processed through Pearson correlation and factor analysis. Gibbs diagram, Piper plot, partial pressure of carbon dioxide, and saturation index of carbonate minerals were also employed to determine the geochemical characteristics and dominant processes operating in the river basin. Higher mean EC value of 129.28 μS/cm in S3 and higher mean pH (6.77) in S1 were observed. The results show spatial and temporal variations in analyzed parameters but are within tolerable limits of the Malaysian water quality and WHO standards. A decreasing order of HCO3- > Cl- > Na+ > Mg2+ > Ca2+ > K+ was noted in the mean concentration of major ions, whereas the mean concentration of trace metals follows the order of Fe > Ni > Pb > Mn > Zn > Co > Cu > Cd. Higher mean concentration of HCO3 (47.09 mg/L) in S2 and higher mean concentration of Fe (1.77 mg/L) in S1 were observed. The Pearson correlation test (r ≥ ± 0.70) shows varying relationships among the parameters and is different in three sampling periods. Piper diagram revealed two distinct chemical facies such as mixed Ca2+-Mg2+-Cl- and Ca2+-Mg2+-HCO3- irrespective of seasons. At the same time, Gibbs plots indicated dominant control of precipitation (rainfall) with an influence of mineral dissolution over the surface water chemistry. An increasing trend of log pCO2 values from upstream to downstream shows the direct recharge of rainwater with lower log pCO2 values in the upstream side and mixed water with higher log pCO2 in the downstream side. The saturation index indicates the under-saturated state of the carbonate minerals in the order of SIMagnesite > SICalcite > SIAragonite > SIDolomite and suggesting the effect of dilution through monsoon rainfall. Factor analysis revealed the dominance of high sediment load in response to severe rainfall, weathering, leaching and dissolution of bed rocks, hydrolysis of organic nitrogen through decomposition of microorganisms, and the aerobic decomposition of organic nitrogenous matter and atmospheric fallout as the major contributors of surface water geochemistry.

Hydrogeochemical Processes and Trace Metal Contamination in Groundwater: Impact on Human Health in the Maputaland Coastal Aquifer, South Africa

The main objective of the study is to evaluate the hydrogeochemical processes and potential health risk assessment for humans in groundwater of Maputaland coastal aquifer, South Africa. In this study, 53 and 42 groundwater samples were collected from bore wells during 2018 and 2019 and were analysed for major ions, minor ions, nutrients and trace metals. Na–Cl water type was dominant in groundwater followed by Ca–HCO3. Cross plots revealed that ion exchange, reverse ion exchange, silicate weathering, seawater mixing and anthropogenic inputs from agricultural activities govern the groundwater chemistry. GIS methods were adopted to produce spatial distribution maps of major ions through which locations of groundwater contamination and the intensity of hydrogeochemical processes were identified. Mean concentration of trace metals were in the order: Zn > Li > Al > Fe > Mn > Cu > Pb > As > Co > Cd in 2018, Fe > Zn > Mn > Sr > B > Pb > Cu > Co > Cr > Cd > Ag > Al > Ni in 2019. Most of the trace metals were found to be within the WHO standards for drinking water except Cd, Zn, Pb, Mn, Al and Fe. Health risk assessment of trace metals in groundwater via ingestion and dermal absorption pathways were carried out. Hazard Quotients (HQs) and Hazard Index (HI) of all trace metals were below 1, except HQingestion and HI for Co and Pb which were greater than 1 in children. This suggests that these metals pose adverse risks to local people, and children were more sensitive to risks than adults. HI values for adults and children were medium indicating high risk. This is the first baseline study conducted in the study area which identifies the chemical characterization and the potential health risk due to trace metals contamination.

Chronic Kidney Disease of undetermined cause (CKDu), an emerging disease in developing nations

OPS 25: Drinking water contamination and adult health, Room 411, Floor 4, August 26, 2019, 10:30 AM - 12:00 PM Background: There is increasing recognition of epidemics of primarily tubular-interstitial chronic kidney disease (CKD) clustering amongst working-age populations in agricultural communities in low-and-middle-income countries. These conditions have been termed CKD of undetermined cause (CKDu) due to unidentified underlying aetiology. Hypothesised causes include heat stress and heavy metal exposure through potable water. Our aim was to investigate CKDu presence in Malawi, and identify potential risk factors including nephrotoxic heavy metals in potable drinking water. Methods: Blood and urine samples (n=770) taken from an urban and rural study site (January-August 2018) were used to estimate kidney function across the sample population. We applied linear and logistic regression models with postulated risk factors including age, sex, education, residence, vegetarianism, and body mass index to estimate risk of low glomerular filtration rate (eGFR) (<90 ml/min/1.73m2). We collected potable water samples which were tested for trace metals by Nottingham University. We analysed the spatial distribution of trace metals across the study area using inverse distance weighting with standardised z-scores. Results: Mean eGFR was 117.1±15.83ml/min/1.73m2. Prevalence of low eGFR was 5% (95%CI = 3.0, 6.2), and did not vary substantially between sites. Factors associated with low eGFR included low income (<10,000 Malawian Kwacha) [OR (95%CI) = 0.16 (0.02, 1.07)]; and age [4.87 (0.39, 6.00)] per 10-year increase. Mean trace metal concentrations did not exceed permissible limits. However, some sites contained nephrotoxic metal concentrations which neared limits, including Cadmium (2.66µg/L, World Health Organisation limit 3.00µg/L). Conclusions: Reduced kidney function in the absence of known risk factors (eGFR <90 ml/min/1.73m2) was observed across our study area, however little difference in risk between sites was observed. No known nephrotoxic trace metals exceeded permissible limits, however, analyses of heavy metals concentrations in bio samples will be conducted to rule these out as risk factors for reduced kidney function in Malawi.

Heavy metal bio-accumulation in the kidneys of scaly and non-scaly fishes from Epe Lagoon, Nigeria

Introduction: Heavy metal contamination of aquatic ecosystems has been a serious concern throughout the world for many decades, and has caused devastating effects on aquatic organisms. Objective: To evaluate the levels of Cu, Zn, Fe, Pb and Cd in the kidneys of scaly (T. zillii, M. rume and R. ocellatus) and non-scaly (C. gariepinus, Ch. nigrodigitatus and S. filamentosus) fishes in Epe lagoon, Nigeria to understanding the bioaccumulation potential of the kidney relative to other organs in fish that have previously been reported in literature. Methods: We studied concentrations of copper (Cu), iron (Fe), zinc (Zn), cadmium (Cd) and lead (Pb) in the kidneys of 141 scaly fishes (Mo. rume, R. occellatus, T. zillii) and 134 non-scaly fishes (C. gariepinus, S.filamentosus, Ch. nigrodigitatus) and water samples obtained from Epe Lagoon using Standard Atomic Absorption Spectrometry methods. Results: The kidneys of R. ocellatus had the highest levels of Fe (2,92±0,10) and Cd (0,18±0,03), while that of Ch. nigrodigitatus (2,78±0,02) and T. zillii (0,31±0,02) had the lowest concentration of Fe and Cd respectively. T. zillii and M. rume accumulated Cu and Zn in their kidneys respectively more than the others. There was no significant difference (p&lt;0,05) in mean trace metal concentrations among the scaly and non-scaly fishes. The concentrations of metals in fish specimens were below the FEPA and WHO prescribed maximum allowable limits in food fish. Dissolved oxygen (9,0±0,02) and total alkalinity (24,0±0,01) were above FEPA values (dissolved oxygen: 3,0-5,0mg/L and total alkalinity: 3,05-5,3mg/L). The ranking of heavy metals distribution in the water body was Cu (4,70)&gt;Fe (0,72)&gt;Zn (0,13)&gt;Pb (0,007)&gt;Cd (0,006). Bioconcentration factor of Zn was generally high in all species. Conclusion: Close monitoring of these metals in the fishes and the lagoon is important to ensure the safety of fish consumers in the area.

Catchment soils as a factor of trace metal accumulation in sediments of the reservoir Klingenberg (eastern Ore Mountains, Germany)

The release and accumulation dynamics of trace metals in soils and aquatic sediments were exemplarily investigated in the catchment area of the Reservoir Klingenberg (Germany). Catchment soils were examined for mobilizable and total concentrations of arsenic (As), cadmium (Cd), chrome (Cr), iron (Fe), manganese (Mn), nickel (Ni), lead (Pb), and zinc (Zn) and compared with trace metal quantities accumulated in riverbed and reservoir sediments. The comparison of all samples showed relatively small variations of Cr (7.96–46.0 mg/kg), Fe (7.79–40.4 g/kg), and Ni (6.06–56.5 mg/kg), while stronger differences were found for As (11.2–164 mg/kg), Cd (0.14–30.5 mg/kg), Mn (0.08–1.84 g/kg), Pb (20.7–183 mg/kg), and Zn (69.1–916 mg/kg). The catchment soils were slightly enriched by Cd, Pb, and Zn. Especially Cd and Zn were characterized by large mobilizable proportions. The mean trace metal concentrations in riverbed sediments were higher than in catchment soils, while reservoir sediments accumulated the highest amounts of the analyzed elements. The enrichment of trace metals in reservoir sediments was generally determined by the sedimentation of fine particles, while the distribution of As, Fe, and Mn was additionally impacted by redox conditions. For Cd and Zn, which in comparison were most enriched in riverbed and reservoir sediments, a significant release from soils by leaching processes was observed. The accumulation of As and Pb in reservoir sediments was influenced to a greater extent by soil erosion and by anthropogenic or chalcogen sources in the catchment.

Trace Metal Contamination and Risk Assessment of an Urban River in Limpopo Province, South Africa.

Ecological and human health risk assessments were undertaken in an urban river, Sand River. Suitability of river water for irrigation was also determined. Samples were taken on a monthly basis from four sites. Site 1 was upstream of a sewage treatment plant, sites 2, 3 and 4 were downstream. The mean concentrations of trace metals in Sand River water after sewage effluent discharge followed the order Fe > Mn > Pb > Cu > Zn ≥ Cd. Trace metal concentrations in the sediment, grass and fish after discharge followed the order Fe > Mn > Zn > Cu > Pb > Cd. The geo-accumulation index showed that the sediment was not contaminated with trace metals. The health risk assessment index showed that consumption of fish from the Sand River was risky because of the high lead levels. Sodium adsorption ratio and soluble sodium percentage were 2.54% and 49.7% respectively. Both these values indicate that Sand River water is suitable for irrigation after effluent discharge.

Monitoring of seasonal variation of some trace metals concentration in surface water collected from the coastal area of Bangladesh

This study was conducted to determine the seasonal variation of Cr, Ni, Cu, Zn, As, Cd and Pb concentrations in water from four coastal sites of Bangladesh. The mean concentrations of trace metals in the water samples in the range of each elements were Cr (2.6−15.3), Ni (5.1−77.5), Cu (10.2−510), Zn (5.0-1390), As (2.1−13.3), Cd (0.006−0.09), Pb (0.4−109 μg/l) in summer and Cr (3.6−43.7), Ni (10.8−42.4), Cu (7.3−45.2), Zn (18.0-73.9), As (4.0−19.7), Cd (0.025−0.087), Pb (2.8−34.8 μg/l) in winter. The mean concentrations of the metals in water followed a decreasing order of Zn &gt; Cu &gt; Pb &gt; Ni &gt; Cr &gt; As &gt; Cd in the summer and Zn &gt; Ni &gt; Cr &gt; Cu &gt;Pb &gt; As &gt; Cd in the winter. The water of Cox’s Bazar hatchery site showed the highest levels of Zn (1390), Cu (510) and Pb (109 μg/l) in summer while As (19.7 μg/l) showed highest in Cox’s Bazar Bakkhali estuary in the winter samples. The elevated level of Ni (77.5 μg/L) in the summer and Cr (43.7 μg/l) in the winter water samples were also found in the Sundarbans site. The mean concentrations of all estimated trace metals were higher in the winter than in the summer season. It was both in the Chittagong port and Meghna estuary. For the Meghna estuary, the highest concentration of Zn (36.0 μg/l) was observed in the water sample of winter season. Some trace metals exceeded the international quality guidelines. Suspended solid, temperature, rainfall, anthropogenic inputs and geomorphologic setup are influenced by seasonal vagaries which alter the variation of metal distribution.&#x0D; J. Biodivers. Conserv. Bioresour. Manag. 2018, 4(2): 67-80

Evaluation of potentially toxic element contamination in the riparian zone of the River Sava

Contaminated sediments transported onto the river terrace during high water events can contribute significant quantities of potentially toxic elements to riparian soils. Seven trace elements (As, Cd, Cr, Cu, Ni, Pb and Zn) were analysed in the river sediment and riparian soil of the River Sava and their spatial distribution, potential toxicity and ecological risk levels were evaluated. The results showed that levels of all the trace metals were enriched to varying extents in both the sediment (As, Cr, Ni, and Pb) and soil (Ni) when compared to reference levels for sediments and European soils. Mean concentrations of trace metals in sediment and soil, apart from Pb, increased downstream in the River Sava. The similar increasing trend of these elements in sediment and soil may be explained by their increased load due to anthropogenic pressures (As, Cr, Ni, Pb and Zn in sediment and the significant accumulation of Ni in soil) and frequent periodic flooding (As, Cd, Cr, Cu, Ni and Zn in sediment and Cd in soil are influenced by both high water events and natural factors such as the geological substrate), particularly in lowland regions. In this study, soluble As, Cd, Cr, Cu and Ni fractions in sediment and soil <10% indicated their low mobility. The exceptions were readily soluble Pb and Zn in the sediment and soil at some sampling sites. In the lower reaches, levels of Pb in sediment was indicative of a medium environmental hazard, while there was a high environmental hazard in the upper reaches with the average Pb content in sediment higher than the PEL. Pollution factors for Pb in soil indicated a medium environmental hazard in the upper and middle reaches and a high environmental hazard at some sites in the lower stretches of the Sava River, although total Pb content in soil was within the range proposed for European soils.

Assessment of trace metal contamination in the sea cucumber (Holothuria tubulosa) and sediments from the Dardanelles Strait (Turkey).

This study was performed to determine the concentrations of some trace metals (Cd, Cu, Pb, Ni, Zn, and Fe) in Holothuria tubuosa (Gmelin, 1788) belonging to Echinoderm species and in sediments that they live at three different stations (Gelibolu, Umur Bey/Lapseki, and Dardanos) on Dardanelles Strait between April 2013 and March 2014. The mean trace metal concentrations determined in H. tubulosa and sediment were as follows: Cd 0.18mg/kg, Cu 2.43mg/kg, Pb 2.09mg/kg, Ni 14.58mg/kg, Zn 16.86mg/kg, and Fe 73.46mg/kg and Cd 0.70mg/kg, Cu 5.03mg/kg, Pb 14.57mg/kg, Ni 27.15mg/kg, Zn 54.52mg/kg, and Fe 3779.9mg/kg, respectively. It was detected that the statistical difference between trace metals determined seasonally in muscle tissue of H. tubulosa was significant (p > 0.05). As a result of the study, it was detected that H. tubulosa is a bioindicator species in determining Ni trace metal in sediment. The results were compared to the limit values of National and International Food Safety, and it was detected that Cd and Ni concentrations measured in sediment were above LEL of Ni and Cd concentrations according to Sediment Quality Guidelines.

Bioaccumulation of Trace Metals in Selected Plants within Amin Bazar Landfill Site, Dhaka, Bangladesh

The presence of trace metals in landfill soil and plants pose a risk to the environment and human health. This study was conducted to determine trace metal concentrations in soil and different plant parts that grow in the Amin Bazar landfill, Bangladesh, to evaluate the possible human health risk on consumer. The collected soil and plant samples were analyzed for trace metals using a Flame Atomic Absorption Spectrophotometer. The mean concentrations of trace metal found in the soil were in the following order: zinc (Zn) > manganese (Mn) > lead (Pb) > copper (Cu) > chromium (Cr) > nickel (Ni). Considering all selected plant species, the mean concentrations of trace metals were in the following order: Zn > Ni > Mn > Cu. On the other hand considering all measured trace metals, the accumulation trend in plant species were in the following order: Carica papaya > Enhydra flactuans > Amaranthus gangeticus > Ipomoea aquatica > Sesbania cannabina > Musa sapientum. Pb and Cr were not accumulated in the studied plant species. Translocation factor (TF), bioaccumulation factor (BAF) and bioaccumulation coefficient (BAC) were calculated for the assessment of mobility of trace metals from root to shoot, soil to shoot and soil to whole plant, respectively. TF values showed that the plant species effectively translocate trace metals from roots to the shoots, suggesting that they are suitable for phytoextraction. According to BAF all studied plants were excluders for all metals except Ni, and according to BAC, all studied plants were hyperaccumulators of Ni. The daily metal intake and health risk index values of the studied metals, except of Ni, indicated that there is a relative absence of health risks associated with the ingestion of contaminated edible parts of plants.

Phytochemical, trace metals assessment and antimicrobial efficacy of Barleria cristata

Traditional plants contains various secondary metabolites which have shown significant pharmacological activity. In the present paper, we analysed the phytochemical, trace metal and antimicrobial activity of ethanolic leaf extracts of Barleria cristata. The significance of high antimicrobial activity due to their presence of secondary metabolites in this herb. The phytochemical screening revealed the presence of steroids, triterpenes, alkaloids, phenols, flavonoids, saponin, tannins and amino acid. The antimicrobial activity of B.cristata ethanol extract was examined with six various pathogenic microorganisms such as gram positive, gram negative and fungal strains using the disk diffusion test. The two tested concentrations such as 0.60 and 1.20 mg/disc produce zone of inhibition on Muller Hinton Agar (MHA) and Potato Dextrose Agar (PDA) plates for bacteria and fungi, respectively. In this study, higher (1.20 mg) concentration got greater sensitivity than lower (0.60 mg) concentration against all strains. The trace metal analyses of the plants were also carried out. The mean concentration of trace metals such as cadmium (Cd), chromium (Cr), copper (Cu), iron (Fe), nickel (Ni), lead (Pb) and zinc (Zn) were 0.05, BDL, 0.07, 0.88, BDL, 0.23 and 0.24 mg kg -1 , respectively. Therefore, it is signified that B.cristata plant extract is safe to be used as an antimicrobial agent.

Distribution and Pollution Assessment of Trace Metals in the Surface Sediments around Farming Area of Jinhae Bay

Trace metals(As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Pb and Zn) concentrations in surface sediments of Jinhae bay in August of 2013 were measured to investigate the characteristics of trace metals distribution and to evaluate the metal pollution. Assessment for metal pollution was carried out using the sediment quality guidelines(SQGs) such as threshold effects level(TEL) and probable effects level(PEL) proposed by the ministry of onceans and fisheries(MOF) in Korea and geochemical assessment techniques(enrichment factor(EF) and geoaccumulation index ()). The mean concentration of trace metals in the sediments are as follows: 11.1 mg/kg for As, 0.52 mg/kg for Cd, 14.1 mg/kg for Co, 69.8 mg/kg for Cr, 57.2 mg/kg for Cu, 3.7 % for Fe, 0.064 mg/kg for Hg, 600 mg/kg for Mn, 40.1 mg/kg for Pb, 167.2 mg/kg for Zn. The spatial distributions of As, Co, Cr and Fe were not distinguished clearly in whole area. However, Cd, Hg, Pb and Zn were high in northern area of bay, and Cu and Mn were high in southeastern and eastern area of bay, respectively. The distribution pattern of trace metals, correlation matrix and R-mode factor analyses results revealed that the distribution of trace metals were mainly effected by the sediment grain size(Co, Cr and Fe), redox condition of sediments(Mn) and anthropogenic factors(As, Cd, Cu, Hg, Pb and Zn). Comparing the concentrations of several trace metals(As, Cd, Cr, Hg and Pb) with SQGs from Korea(TEL and PEL), the concentrations of Hg, Cd and Pb in sediment of northern area of bay were higher than TEL. EF and values of As, Cd, Cu, Hg, Mn, Pb and Zn showed that these metals in sediments are enriched by anthropogenic activities in some areas, and pollution status for Cd, Hg and Pb in northern area and Cu in southeastern area of bay were concerned about current level, although those for As, Mn and Zn were not.

Trace metal Levels in Some Packaged Fruit Juices Sold in Makurdi Metropolis Markets, Nigeria

The concentrations of ten (10) trace metals (Cr, Mn, Fe, Co, Ni, Cu, Zn, Se, Cd and Pb) in samples of commonly consumed fruit juices in Nigeria were determined using Atomic Absorption Spectrophotometric (AAS) technique. The mean concentration (mg/L) of the trace metals in the samples analyzed were as follows: Cr (0.172±0.05), Mn (2.29±1.0), Fe (14.4±7.9), Co (0.739±0.29), Ni (0.217±0.17), Cu (0.758±0.47), Zn (1.79±1.3) and Se (0.385±0.25). However, Cd and Pb were below the detection limit of the AAS and therefore not detected in all the juice samples analyzed. The mean concentrations of trace metals in descending order for all the fruit juices samples analyzed was; pineapple > orange > apple. Similarly, the pattern of mean concentrations of trace metals for the six different brands investigated were coded as follows: Ceres (CR) > Chivita (CH) > Fumman (FU) > Frutta (FR) > Soy good (SG) > Nature’s fresh (NF). Some of the results obtained were comparable to those found in the literature, but urgent attention is required to address high metal content found in pineapple juice of one brand (CR). Keywords : Atomic Absorption Spectrophotometric, Fruit Juice, Makurdi, Nigeria, Trace metals.

Assessment of Trace Metals Concentration in Tree Barks as Indicator of Atmospheric Pollution within Ibadan City, South-West, Nigeria.

Tree bark species were randomly collected from 65 sites having different anthropogenic activities, such as industrial, high traffic commercial, residential high and residential low traffic volume areas of Ibadan City, Nigeria. Levels of Cd, Cu, Pb, Zn, Co, and Cr of the dry-ashed bark samples were determined by AAS. The mean metal concentrations (mg kg−1) in samples from industrial zone were found as Pb: 3.67 ± 1.97, Cd: 0.10 ± 0.07, Zn: 30.96 ± 32.05, Cu: 7.29 ± 5.17, Co: 0.91 ± 0.58, and Cr: 2.61 ± 1.84. The trend of mean trace metal concentrations at high traffic commercial zone follows the order: Zn > Pb > Cu > Cr > Co > Cd. Residential high traffic and low traffic zones revealed the same trend as Cd < Co < Cr < Pb < Cu < Zn. Relatively strong positive correlation between the heavy metals at ρ < 0.05, such as Zn versus Cu (r = 0.79) and Co versus Cu (r = 0.77), was observed. The results of the study suggest that tree bark samples could potentially serve as bioindicators for Cu, Pb, Zn, Cr, and possibly Co and Cd. Furthermore, interspecies variation of heavy metal concentrations in plants barks is recommended.