Mean Concentrations Of Pb Research Articles

Assessment of Heavy Metal Pollution in Urban Agricultural Soils of Jilin City, China

ABSTRACTDue to rapid industrialization and urbanization during the last two decades, contamination of urban agricultural soils by heavy metals is on an increase all over China. In this study, fifty soil samples were collected from urban vegetable fields in a chemical industrial area and non chemical industrial area in Jilin City to investigate the heavy metal pollution level. The mean Pb, Cr, Cu, Ni, Zn, and Cd contents (30.84, 65.65, 26.41, 23.07, 135.14, and 0.1434 mg kg−1 dry weight, respectively) in the urban vegetable soils were higher than their corresponding natural background values. The principal component analysis (PCA) was performed to identify the possible sources of metal contamination in the study area. The results indicated that Cu and Zn were mainly from industrial activities, while Pb and Cd were derived from traffic activities and agricultural activities, and Cr and Ni tended to be from parent material. The distribution of comprehensive pollution index values showed that Pb, Cr, Cu, Ni, Zn, and Cd concentrations in most of the agricultural fields did not exceed the baseline values affecting the safety of agricultural production and human health according to the soil environmental quality standard of China, indicating an insignificant contamination of these metals in Jilin City.

Determination of Environmental Deposition of Lead (Pb) in Certain Selected Samples in the Industrial Areas of Gazipur District of Bangladesh

Hasty industrialization affects the environment in different ways by discharging the large quantity of effluents as dissipate water in the surrounding water bodies, causing the solemn problems to environment. Twenty (n=20) samples of each category were collected from different locations of Gazipur. 3-5 goat of each sample was considered for analytical procedure. The results of analysis of variance of mean Pb-concentration in different samples collected from different locations differed significantly (P<0.05). The detected mean value of lead (Pb) concentration in drinking water (ground water), surface water, industrial waste water and agricultural soil (crop land) was 0.048±0.005mg/L ml/L, 0.428±0.098 ml/L, and 38.859±5.766 ml/L and 79.059±16.261 mg/kg. The mean value of concentrations of lead (Pb) was also detected in poultry tissue and litter samples. The highest level of lead (Pb) concentration was found in bone followed by brain, kidney, liver and muscles. The detected mean value of lead (Pb) in bone, brain, kidney, liver and muscles were 0.082±0.005 mg/kg, 0.073±0.007 mg/kg, 0.071±0.007 mg/kg, 0.052±0.011 mg/kg and 0.038±0.005, respectively. As regards biological samples, the highest natural accumulation of lead (Pb) was found in chicken bone while the lowest concentration (Pb) was detected in muscles. The natural accumulation of Pb was highly and significantly (P<0.001). The poultry litter (0.580±0.059 mg/kg) was also detected significantly (P<0.05) as a major toxic agent in respect of lead (Pb) for environmental degradation due to the use of poultry litter in agricultural soil (crop land) to grow more crops and vegetables.

Fetal Exposure to Environmental Neurotoxins in Taiwan

Mercury (Hg), lead (Pb), cadmium (Cd), and arsenic (As) are recognized neurotoxins in children that particularly affect neurodevelopment and intellectual performance. Based on the hypothesis that the fetal basis of adult disease is fetal toxic exposure that results in adverse outcomes in adulthood, we explored the concentrations of key neurotoxins (i.e., Hg, Pb, Cd, and As) in meconium to identify the risk factors associated with these concentrations. From January 2007 to December 2009, 545 mother-infant pairs were recruited. The geometric mean concentrations of Pb and As in the meconium of babies of foreign-born mothers (22.9 and 38.1 µg/kg dry weight, respectively) were significantly greater than those of babies of Taiwan-born mothers (17.5 and 33.0 µg/kg dry weight, respectively). Maternal age (≥30 y), maternal education, use of traditional Chinese herbs during pregnancy, and fish cutlet consumption (≥3 meals/wk) were risk factors associated with concentrations of key prenatal neurotoxins. The Taiwan government should focus more attention on providing intervention programs for immigrant mothers to help protect the health of unborn babies. Further investigation on how multiple neurotoxins influence prenatal neurodevelopment is warranted.

Trace elements and heavy metals in mineral and bottled drinking waters on the Iranian market

A survey of Iranian waters, sampled from 2010 to 2013, is presented. A total of 128 water samples from 42 different brands of bottled mineral and drinking water were collected and analysed for contamination levels of lead (Pb), cadmium (Cd), copper (Cu), arsenic (As) and mercury (Hg). Determinations were performed using a graphite furnace atomic absorption spectrophotometer for Pb, Cd and Cu, a hydride vapour generation as well as an Arsenator digital kit (Wagtech WTD, Tyne and Wear, UK) for As and a direct mercury analyser for Hg. Arsenic concentration in six bottled gaseous mineral samples was higher than the related limit. Regardless of these, mean concentrations of Pb, Cd, Cu, As and Hg in all types of water samples were 4.50 ± 0.49, 1.08 ± 0.09, 16.11 ± 2.77, 5.80 ± 1.63 and 0.52 ± 0.03 µg L−1, respectively. Values obtained for analysed heavy metals in all samples were permissible according to the limits of national and international standards.

A Comparative Study on the Physicochemical Parameters and Trace Elements in Raw Milk Samples Collected from Misurata- Libya

This research work was carried out to compare the physicochemical parameters of milk samples from four different animal species namely cow, goat, camel and sheep. Milk samples were collected from different areas of Misurata, Libya and analyzed for the key physiochemical parameters, pH, titratable acidity, total solids, ash, fat, protein and lactose. Furthermore in this study the concentrations of Zinc (Zn), Cadmium (Cd), Chromium (Cr), Magnesium (Mg), Manganese (Mn), Potassium (K), Calcium (Ca) Copper (Cu), Iron (Fe) and Lead (Pb) in similar commercial milk specimens from the same area were determined using microwave plasmaatomic emission spectrometry In fresh cow’s milk, the mean concentrations of Pb, Cd, Cr, Cu, Fe, Zn, Mg, Mn, Ca and K were 0.13± 0.19 (mg/l), 0.004± 0.001 (mg/l), 0.04± 0.01 (mg/l), 0.17± 0.11 (mg/l), 0.72± 0.02 (mg/l), 1.98± 0.04 (mg/l), 214.00± 0.20 (mg/l), 0.080± 0.05 (mg/l), 423.0± 3.5 (mg/l) and 427.0± 2.5 (mg/l), respectively. While the mean concentration of Pb, Cd, Cr, Cu, Fe, Zn, Mg, Mn, Ca and K, in the goat’s milk were 0.761 ± 0.78 (mg/l), 0.085 ± 0.02 (mg/l), 1.253 ± 0.18 (mg/l), 0.400± 0.08 (mg/l), 1.23± 0.21 (mg/l), 3.110± 0.15 (mg/l), 140.0± 0.31 (mg/l), 0.097± 0.07 (mg/l), 473± 5.12 (mg/l) and 510± 6.05 (mg/l), respectively. The concentration of Pb, Cd, Cr, Cu, Fe, Zn, Mg, Mn, Ca and K, in the camel’s milk were 0.025 ± 0.019 (mg/l), 0.091± 0.05 (mg/l), 0.069± 0.07 (mg/l), 0.080 ± 0.05 (mg/l), 1.680 ± 0.43 (mg/l), 5.380 ± 1.17 (mg/l), 120.0 ± 0.11 (mg/l), 0.094 ± 0.04 (mg/l), 520.0 ± 0.32 (mg/l) and 571.0± 0.81 (mg/l), respectively. The concentration of Pb, Cd, Cr, Cu, Fe, Zn, Mg, Mn, Ca and K, in the sheep’s milk were 0.062± 0.03, 0.106± 0.11, 0.040± 0.01, 0.201± 0.10, 0.880± 0.31, 5.350± 0.50, 180± 1.20, 0.072± 0.01, 478± 3.10, and 593.96± 1.87, respectively.

Determination of some heavy metal levels in soft drinks on the Ghanaian market using atomic absorption spectrometry method.

Twenty-three soft drink samples (i.e., four pineapple-based fruit drinks, eight citrus-based fruit juices, one soya-based drink, three cola carbonated drinks, one apple-based fruit drink, and six cocktail fruit drinks) were randomly purchased from retail outlets in an urban market in Accra and analyzed for the concentrations of iron, cobalt, cadmium, zinc, lead, and copper using flame atomic absorption spectrometry. The mean concentration of iron and cadmium were 0.723 ± 0.448mg/L and 0.032 ± 0.012mg/L, respectively. The mean cobalt concentration was 0.071 ± 0.049mg/L, while the mean Zn concentration in the samples was 0.060 ± 0.097mg/L. The mean concentrations of Pb and Cu in the fruit juice samples were 0.178 ± 0.091mg/L and 0.053 ± 0.063mg/L respectively. About 78% of the samples exceeded the United States Environmental Protection Agency (USEPA) maximum contaminant level of 0.3mg/L prescribed for iron, whereas all the samples exceeded the USEPA maximum contaminant level of 0.005mg/L prescribed for cadmium. About 91% of the samples exceeded the EU maximum contaminant level prescribed for lead insoft drinks.

Grain-size distribution and heavy metal contamination of road dusts in urban parks and squares in Changchun, China.

Due to rapid urbanization and the scarcity of land, most of the urban parks and squares in cities are built close to major roads or industrial areas, where they are subject to many potential pollution sources, including vehicle exhaust and industrial emissions. The aims of this study were to determine the concentrations of selected metals (Pb, Cr, Cu, Ni, Zn, and Cd) in road dusts collected in urban parks and squares in Changchun, China, on June 1, 2013 (International Children's Day) and to estimate the pollution sources. The mean Pb, Cr, Cu, Ni, Zn, and Cd contents (70.89, 60.30, 43.56, 23.16, 170.80, and 0.3111 mg kg(-1) dry weight, respectively) in urban dusts were higher than their corresponding natural background values, particularly Pb, Cu, Zn, and Cd, which had about 2.5, 1.4, 1.9, and 2.6-fold higher levels, respectively. The results of principal component analysis indicated that Cr and Ni concentrations were mainly of natural origin, while Pb, Cu and Zn were derived from anthropogenic activities, and Cd tended to be from both sources. The geoaccumulation index (I geo) of these metals in the urban dusts under study indicates that they are uncontaminated with Cr and Ni; uncontaminated to moderately contaminated with Cu and Zn; and moderately contaminated with Pb and Cd. In addition, five particle sizes were analyzed separately for heavy metal concentrations. In all studied areas, there are large differences in the metal-loading percentage of different particle-size fractions among the samples, and the particles in 250-2,000-μm fraction are dominant in the total metal loading.

Determining prenatal, early childhood and cumulative long-term lead exposure using micro-spatial deciduous dentine levels.

The aim of this study was to assess the validity of micro-spatial dentine lead (Pb) levels as a biomarker for accurately estimating exposure timing over the prenatal and early childhood periods and long-term cumulative exposure to Pb. In a prospective pregnancy cohort sub-sample of 85 subjects, we compared dentine Pb levels measured using laser ablation-inductively coupled plasma mass spectrometry with Pb concentrations in maternal blood collected in the second and third trimesters, maternal bone, umbilical cord blood, and childhood serial blood samples collected from the ages of 3 months to ≥6 years. We found that Pb levels (as 208Pb:43Ca) in dentine formed at birth were significantly associated with cord blood Pb (Spearman ρ = 0.69; n = 27; p<0.0001). The association of prenatal dentine Pb with maternal patella Pb (Spearman ρ = 0.48; n = 59; p<0.0001) was stronger than that observed for tibia Pb levels (Spearman ρ = 0.35; n = 41; p<0.03). When assessing postnatal exposure, we found that Pb levels in dentine formed at 3 months were significantly associated with Pb concentrations in children’s blood collected concurrently (Spearman ρ = 0.64; n = 55; p<0.0001). We also found that mean Pb concentrations in secondary dentine (that is formed from root completion to tooth shedding) correlated positively with cumulative blood lead index (Spearman ρ = 0.38; n = 75; p<0.0007). Overall, our results support that micro-spatial measurements of Pb in dentine can be reliably used to reconstruct Pb exposure timing over the prenatal and early childhood periods, and secondary dentine holds the potential to estimate long-term exposure up to the time the tooth is shed.

Lead concentration in meat an meat products of different origin

Meat is very rich and convenient source of nutrients including also a large extent of microelements. Contamination with heavy metals is a serious threat because of their toxicity, bioaccumulation and biomagnifications in the food chain. The lead concentrations depend on the environmental conditions and the food production methods. Ingestion of contaminants, especially heavy metals, by animals causes deposition of residues in meat. The aim of this study was to determine the levels of lead in the Malokarpatska and Lovecka salami during the technological processing with comparison to the raw materials originating from domestic and foreign production. Lead content was determined by atomic absorption spectrometry. The starting materials in the Malokarpatska salami were found to contain the highest level of lead in the beef of foreign production (7.58 ppb), followed pork from foreign production (3.43 ppb), beef from domestic production (3.27 ppb), pork bacon from foreign production (2.41 ppb), pork from domestic production (1.63 ppb) and pork bacon from domestic production (1.57 ppb). The average concentration of lead was higher in homogenized samples with addition of additives and spices and ranged between 6.49 to 7.56 ppb. The lead concentration in final product Malokarpatska salami was in the range from 8.57 to 8.89 ppb. The highest mean Pb concentrations in the Lovecka salami in the starting materials were beef from foreign production, beef from domestic production, pork from foreign production, pork bacon from foreign production, pork from domestic production and pork bacon from domestic production (7.31, 3.77, 3.21, 2.40, 2.03, 1.97 ppb, respectively). Increasing concentration of lead was found after the addition of additives, spices and curing compounds causing a threefold increase in the concentration of lead in final products Lovecka and Malokarpatska salami. Technological process of meat processing can create a potential source of heavy metals in final products. Improvements in the food production and processing technology are increasing the chances of food contamination with various environmental pollutants, especially heavy metals.

Radiological and Toxic Risk Assessment of Nigerian Kohl as Cosmetic Compared with Imported Kohl Cosmetics

A total of 38 different samples of Kohl comprising of 23 indigenous mined products and 15 imported products as control and were analyzed for general elemental composition but with particular interest in those reported to be of relevance (As, Cd, Hg, Ni, Co and Sb) in cosmetics. Energy dispersive X-ray Fluorescence Analysis EDXRA was used for the assay. Only Pb, As, Ni and Cr were detected among the elements of interest. Mean Pb concentrations of 277300 ppm; Ni at 2256 ppm concentration; and As at 810 ppm which are considerably higher than their safety limits (20 ppm p<0.01) were obtained in both the indigenous and imported products. The same risk was statistically observed to be involved following the use of both local and imported kohl products. Again Pb concentrations in excess of what was claimed on the labels of the imported kohl products were observed (p<0.01), hence the need for scrutiny of imported products by the relevant agency. The high concentration of Cr (7460 ppm, p<0.05) in the imported samples signifies its presence as colorant and the need for chromium control for the brands concerned. Also the observed presence of Th in the indigenous (local) samples suggests that Nigerian products may be of radiological effect to health. Measurements were made of gross alpha and beta count of indigenous mined and imported kohl samples The results reveals that all the forms of kohl products assayed, emit both particles but with β’s count substantially higher than the α’s (p<0.5) at a mean β count 4695×10-3 cpm and α count as 283×10-3 cpm. One of the samples from Zamfara State of Nigeria (known for Pb poisoning due to mining activities) shows an exceptionally high count in both α = 8998100 cpm and β = 9315700 cpm which reveals that products from Zamfara State, need a special attention. Application of this product is therefore very much likely to produce radiation damage to the cornea due to low penetration of α and to the internal tissue of the eye due to the relatively high penetration of β s. However, the non-existence of defined safety limits for these particles in Kohl as cosmetic, suggests the need for further research.

Concentrations and Health Risk Assessments of Heavy Metals in Fish from the Fosu Lagoon

Concentrations of Cu, Pb, Cr, Cd, Mn, Ni, Fe and Zn were determined in the muscle samples of Sarotherodon melanotheron from the Fosu Lagoon in Cape Coast using atomic absorption spectrophotometer. The results showed that, metal concentration in the fish muscle was in the order Mn > Zn > Fe > Pb > Ni > Cd > Cu > Cr. Mean concentrations of Pb and Cd in the fish exceeded the maximum tolerable limit set by the European Union. Although the mean concentrations of some metals exceeded this limit, their estimated daily intakes were below their oral reference dose recommended by the international regulatory bodies. Health risk assessment of consumers from the intake of metal contaminated in the muscle of S. melanotheron from the lagoon was evaluated by using Health Risk Index (HRI) calculations. In this study, the total HRI through consumption of fish calculated by adding the individual HRIs was less than 1, indicating that there is no significant potential health risk associated with the consumption of fish from the Fosu Lagoon.

Lead in Meat and Meat Products Consumed by the Population in Slovakia

The presence of heavy metals in food is the consequence of atmosphere contamination of polluted soil, waters and results in contaminated feed with heavy metals. The lead concentrations depend on the environmental conditions and the food production methods. The monitoring of lead concentration in meat is important for human health. The aim of this study was to determine the level of lead in the traditional and popular meat products consumed in Slovak republic. This study was carried out to determine the levels of lead in Lovecka salami and selected Ham products during the technological processing. The raw materials originating from domestic and foreign production were compared. Lead concentrations were measured by the method of AA spectrometry with the graphite furnace (Perkin Elmer A Analyst 800; MA, USA). Mean concentration of lead in the starting materials in Lovecka salami for the pork of foreign production had the highest mean lead level (0.607 ppm), followed by beef from foreign production (0.518 ppm), pork from domestic production (0.377 ppm), pork bacon from foreign production (0.173 ppm), beef from domestic production (0.142 ppm) and pork bacon from domestic production (0.106 ppm). The highest concentrations of lead were found in the homogenized samples with addition of additives and spices (salt, sodium ascorbate, erythorbic acid, ground black pepper, sugar, garlic, starter culture) from foreign starting materials and final samples from foreign and domestic production in Lovecka salami (0.769; 0.811 and 0.676 ppm, respectively). The highest concentrations of lead in the selected Ham product were found in final sample from foreign production (0.813 ppm), followed by final sample from domestic production (0.740 ppm), homogenized sample with additives (salt, Sodium Nitrite, Sodium Pyrophosphate, Sodium Tripolyphosphate and Ascorbic acid) from foreign starting material and domestic starting material (0.791 and 0.697 ppm, respectively). The lowest mean Pb concentration in selected Ham was found in the starting materials (pork thigh) from domestic and foreign production (0.344 and 0.397 ppm, respectively). In the present study, samples of lead were higher than the maximum lead levels allowed by Commission Regulations (EC) No1881/2006. The allowable level for lead is 0.1 mg kg-1. Technological process of meat processing can create a potential source of heavy metals risk in final products. Improvements in the food production and processing technology are increasing the chances of food contamination with various environmental pollutants, especially heavy metals.

Concentration of lead, cadmium, and mercury in tissues of European beaver (Castor fiber) from the north-eastern Poland

Abstract The aim of the study was to determine the concentrations of lead (Pb), cadmium (Cd), and mercury (Hg) in the liver, kidneys, and muscles of European beavers (Castor fiber) and thus to evaluate the degree of heavy metals contamination in Warmia and Mazury region in Poland. The study was conducted on free-living beavers captured in region of Warmia and Mazury during autumn 2011. Concentrations of the elements were determined by atomic absorption spectrometry. The presence of the metals was detected in all individual tissue samples. Mean Pb and Hg concentrations were relatively low. However, the high mean Cd level, especially in the kidneys (7.933 mg/kg) and liver (0.880 mg/kg) was demonstrated. Despite the fact that region of Warmia and Mazury is considered to be “ecologically clean”, the conducted studies indicate that systematic monitoring for the presence of heavy metals is necessary not only in industrialised but also in agricultural regions, as well as in natural ecosystems.

Assessment of Heavy Metals in Edible Clays Sold in Onitsha Metropolis of Anambra State, Nigeria

Aim: To determine and compare the levels of zinc (Zn), lead (Pb), cadmium (Cd), copper (Cu), mercury (Hg), and cobalt (Co) in edible clay samples. Place and Duration of Study: Department of Chemistry Laboratory, Federal College of Education (Technical), Asaba between June and October 2013. Methodology: Two species of edible clay (Nzu and Ulo) bought in replicates from four spatially located markets namely Ochanja, Ose, Relief and Okpokoin Onitsha were used for the study. The samples were digested with aqua regia solution and analyzed for heavy metals by atomic absorption spectrophotometry. Mean concentrations were computed from three replicate measurements. Data from the markets were compared by One-Way ANOVA while data between the clay types were analyzed by independent t-test. Results: Mean concentrations (ppm) of Zn, Pb, Cd, Cu, and Co showed no significant difference [(P =.981, .479, .335, .333 and .613) for Zn, Pb, Cd, Cu, and Co respectively] among markets. The mean concentration (ppm) of Hg (2.335±0.276) in Ochanja market however, differ significantly (P =.045) from those of the other markets, 0.621±0.244, Original Research Article British Journal of Applied Science & Technology, 4(14): 2114-2124, 2014 2115 0.796±0.280 and 0.251±0.190 for Ose, Relief and Okpoko respectively. Statistically reliable differences were found for Zn (P =.000) and Co (P =.003) type 1 and 11 mean concentrations. However, mean concentrations of Pb, Cd, Cu and Hg in type 1 and type 11 clays did not differ significantly [(P =.391, .288, .243, and .613) for Pb, Cd, Cu and Hg respectively]. There were high concentrations of Hg invirtually all samples and Cd in few samples. Conclusion: The high levels of Cd and Hgin the analyzed edible clays make them unhealthy for human consumption. However, further research is required to validate the reliability of these findings.

Determination of Concentrations of Heavy Metals in Municipal Dumpsite Soil and Plants at Oke-ogi, Iree, Nigeria

The study examined the concentration of heavy metals [Cd, Co. Cu, Pb, Ni, Mn, Pb and Zn) in dumpsite soil and waterleaf [Talinum triangulare) growing wildly on Oke-ogi dumpsite, Osun state, Nigeria. Soil samples from different layers [0-15cm, 15-30 cm and 30-45 cm) were collected in triplicate and analysed using Atomic Absorption Spectrophotometer. Pb had the highest mean ± SD 91.67±13.80 mgkgfollowed by Zn, which is 20.85±4.80 mgkg. Mean concentration of Pb and Zn in the soil of the control site is significantly lower than [Pb, 10.67±2.08 mgkg) and [Zn, 2.58±0.38 mgkg) respectively. Concentration of Pb in both the dumpsite soil and plant in excess of allowable limit. Concentration of Co in the dumpsite soil [0.02 – 0.72 mgkg). Fe is the most abundant element in the vegetable with a mean value of 186 mgkg followed by Zn [8.63 mgkg). Heavy metal concentrations followed the order of Pb>Zn>Mn>Cu>Cd>Co in the both the control and dumpsite soils most of which falls below the critical permissible concentration level, their persistence in these soils of the dumpsite may lead to increase Original Research Article International Research Journal of Pure & Applied Chemistry, 4(6): 656-669, 2014 657 uptake by plants. Transfer factor for Cd and Mn were 1, while others values are below 1. Elevated heavy metal concentrations at dumpsite need to be properly addressed given the fact, that inorganic waste are being dumped by the people. This can be done if the sitting of dumpsite is regulated, minimizing waste and remediation techniques, such as bioremediation that have shown potential for their ability to degrade and detoxify certain contaminants.

Metals in Honeys from Different Areas of Southern Italy

The aim of the study was to quantify the cadmium (Cd), lead (Pb), chromium (Cr) and arsenic (As) contents in ninety honey samples from nine areas of southern Italy. Results showed that As content was below the detection limit, while Cd, Pb, and Cr contents were below the recommended maximum acceptable levels. Mean Cd, Pb, and Cr contents were 0.013, 0.289 and 0.707 mg kg(-1), respectively. The metal contents in honey varied greatly depending on considered area. Correlations between the metals were statistically significant (p < 0.05), suggesting that polluting sources involve the simultaneous presence of metals in honey.

Identification of Heavy Metals in Wild Plants Grown on Battery Waste

The presence of heavy metals in concentrations higher than their natural level in the environment poses a threat to man, his resources and other components that make up the environment. This study was carried out on wild plants and soil in an abandoned slag deposit site of Exide Battery. Lead (Pb), Cadmium (Cd), Nickel (Ni) and Chromium (Cr) in plant shoots, plant rocks and soil were determined with “Atomic Absorption Spectroscopy”. The trend of accumulation in the plant and soil followed the concentration trend of Pb > Ni > Cr > Cd. The mean concentrations of Pb, Ni, Cr and Cd in the soils were 3262.0 ± 8212.99 mg/kg, 27.89 ± 10.23 mg/kg, 21.65 ± 6.25 mg/kg and 0.60 mg/kg respectively. The mean concentrations of Pb, Ni, Cr, and Cd in plants shoots were 259.21 ± 1012.55 mg/kg, 7.30 ± 10.39 mg/kg, 6.64 ± 10.55 mg/kg and 0.90 ± 1.17 mg/kg respectively. The mean concentrations of Pb, Ni, Cr and Cd in plants roots were: 1515.78 ± 4776.01 mg/kg, 12.86 ± 16.06 mg/kg, 4.60 ± 3.52 mg/kg and 0.76 ± 1.20 mg/kg. From the results obtained it showed that plants have the ability to absorb heavy metals from contaminated soils. Some of these plants had accumulated heavy metals in their tissue but still thrived. The resistant nature and accumulative property of these plants could be looked into and enhanced for phyto-remediation.

The Effect of Spent Engine Oil Discharge on Soil Properties in an Automobile Mechanic Village in Nekede, Imo State, Nigeria

The study investigated the concentration of heavy metal in soil around Nekede automobile mechanic village in Southeastern Nigeria. Sample plots were established in a randomized method along a transect at 100m interval for five (5) different locations within the study area, these sample point were constantly receiving spent engine oil (SEO) and were labeled treatment SA, SB, SC, SD, SE. A composite soil sample was drawn from depths of 0 - 15cm and 15 - 30cm for each of the five treatments. These were air dried, passed through a 2mm sieve and properly labeled for laboratory analysis. Soil samples were then analysed for heavy metal (Pb) using Atomic Absorption Spectrophotometer (AAS). Two (2) soil samples were collected at each sample point and two (2) soil samples CF and CG were also collected 2 km away from the study area in an undisturbed forest as control. Soil pH, cation exchange capacity (CEC) and particle size distribution were also determined. Results showed that the concentrations of Pb from soil samples were random across sample point. The concentration of Pb in the contaminated soil at a depth of 0 - 15cm (topsoil) varies, the highest value was observed at SD (482.2mg/kg) and the lowest value at SE (146.8mg/kg). At the depth of 15 - 30cm (subsoil) concentration of Pb is highest at SB (397.6mg/kg) and lowest at SC (140.1mg/kg). The mean concentration of Pb in the contaminated soil sample has its highest concentration at SB (382.9mg/kg) and lowest at SC (157.8mg/kg). The level of Pb in the control site was lower (CF, 46.5mg/kg and CG, 11.8mg/kg) when compared to the various concentrations of the contaminated soil. pH range was between 5.43 and 6.79. CEC varied across the sample area and showed no variation within the control site. The highest value was observed at CF and CG (3.65cmol/kg) respectively while the lowest value was observed at SA (2.15cmol/kg). The % sand distribution varied across the sample point and showed a higher distribution in the study area than % clay and % silt, the soil texture (sandy loam) was not significantly affected by the SEO. The study concluded that improper disposal of SEO in the study area elevated the soil Pb content thereby causing Lead pollution. Keywords: Spent Engine Oil (SEO), Lead Pollution, Soil properties, auto-mechanic village with a population of about five thousand workers. These workers are mainly motor mechanics which constitute about 60% of the total workforce and includes panel-beaters, welders, automobile electricians, painters, automobile upholstery workers, automobile spare part dealers, vulcanizers and blacksmiths. Complimentary service workers found in the area include confectionaries, commercial phone call service operators, textile dealers, audio and video cassette retailers etc. Most of these artisans and vendors belong to the informal sector of the economy. They neither pay tax, nor register with the government. Their level of education ranges between first school leaving certificate and the senior secondary school certificate, this partly explains the difficulty of

Soil risk assessment of heavy metal contamination near Oil Refinery area, Northeastern India

The present paper aims to maps Cr, Cd, Ni and Pb concentration and assess the hazard in the soils of surrounding agricultural fields affected by oil refinery drainage of Digboi refinery of Tinsukia district, Assam using statistics, geostatistics and GIS techniques. The amounts of Cr, Cd, Ni and Pb were determined from 97 samples collected within the contaminated area. Among the heavy metals studied, the mean concentration of Pb was high. The greatest and the smallest standard deviation were observed in the Ni (44.1) and pH (0.47), respectively. Analysis of the isotropic variogram indicated that the Cr and Cd semivariograms were well described with the circular model, with the distance of spatial dependence being 1240 and 1022 m, respectively, while the Pb and Ni were well describe with Gaussain model, with the distance of spatial dependence being 1930 and 2321 m, respectively. The ordinary kriging maps of Cr, Cd, Ni and Pb showed that high concentrations of heavy metals were located in the low lying area. Indicator kriged probability maps of soil Cr, Cd, Ni and Pb were prepared based on the concentrations to exceed the respective Food and Agriculture Organization maximum permissible limit (MPL) value of 100, 3, 30 and 50 mg kg−1, respectively. It was seen that whole studied area had a higher than 0.99% probability to exceed the MPL value of Pb. About 10% area of the study site was having higher concentration than MPL value of Cd and Ni concentrated at the centre and north-west corner of the study area, respectively.

Evaluation of arsenic, lead and cadmium concentrations in fish samples of Zayanderoud districts

Aims: This research was conducted to evaluate the Arsenic (As), Lead (Pb), and Cadmium (Cd) concentrations in fish flesh samples of Bara'an (east of Isfahan) as a contaminated zone. In addition, the obtained result was compared with a control fish group from behind dam area (west of Isfahan). Material and Methods: In this cross sectional study, 21 fish samples were collected from both the areas and heavy metals concentration was measured by flame Atomic absorption spectrometric method (PERKIN Elmer model 2380). Results: The mean amount of As were 2.97 ± 1.51 and 2.87 ± 0.3 mg/kg in the behind dam and the Bara'an areas, respectively. The mean amount of Pb were 0.66 ± 0.37 and 0.32 ± 0.17 mg/kg in the behind dam and the Bara'an areas, respectively. The mean concentration of Cd were 3.7 ± 4.11 and 86.64 ± 32.4 mg/kg in the behind dam and the Bara'an areas, respectively. The t-test showed no significant differences between the mean concentrations of As in both groups (2.97 Vs 2.87) (P = 0.78). The mean concentrations of Pb in the Bara'an area was significantly less than the behind dam area (0.32 Vs 0.66) (P < 0.001). Instead the mean concentration of Cd in the Bara'an area was significantly more than behind dam area (86.64 Vs 3.7) (P < 0.001). Conclusion: This study confirmed that the fish samples from Zayanderoud at Bara'an and behind dam was contaminated by As, Pb, and Cd. Therefore, we suggest that the heavy metal levels should be monitored regularly.