Mean Values Of Pb Research Articles

Potential of selected microalgae in the bioremediation of wastewater impacted dam water: A case of Goreangab Dam in Windhoek, Namibia

The study was aimed at determining the efficacy of freshwater microalgae in the treatment of polluted dam water with respect to the reduction of pathogen loads, as well as heavy metals and nutrients concentrations. Microalgae were collected from the Klein Windhoek River, as well as the Avis and Goreangab Dams in Windhoek, Namibia. Identification of the microalgae species revealed the presence of the Microcystis species in the Goreangab Dam (control), Anabaena species in the Klein Windhoek River (treatment 1) and the Scenesdesmus species as well as the Anabaena species in the Avis Dam (treatment 2). During treatment, the water samples were assessed on day 0, day 6 and day 12 for faecal and total coliform bacteria, heavy metals (Pb and Cd) as well as nutrients (phosphorous and nitrates). A one-way analysis of variance (ANOVA) indicated that there were no statistical differences between the mean values of Pb (p = 0.346) and Cd (p = 0.940) concentrations after treatment with microalgae. The Kruskal Wallis tests indicated statistical differences between the mean values of the nitrate levels (H(3) = 8.597, p = 0.035) before and after treatment with microalgae. However, the ANOVA indicated that there were no significant differences between the mean values of total phosphate uptake (p = 0.052) after treatment with microalgae. The results for pathogen loads in the wastewater samples indicated statistically significant differences between the mean values of total coliforms ((H(3) = 10.352, p = 0.015) as well as faecal coliforms (H(3) = 10.421, p = 0.015) before and after treatment with microalgae. We conclude that while our microalgae species were not effective in the removal of heavy metals from the dam water, they were nonetheless effective in the removal of microbial contaminants as well as excessive nutrients from wastewater.

Investigation of Lead, Cadmium, and Nickel in Water Samples from Al-Muthanna Governorate, Iraq, and Evaluation of The Pollution Indicators

Background: The Iraqi environment, especially in the southern region, has been contaminated as a result of human activities. The detection of heavy metals in water samples is the preferred method for monitoring the toxic levels, which are very important for environmental protection and human health. Methods: Heavy metal concentrations of lead (Pb), cadmium (Cd), and nickel (Ni) were investigated in water samples from Al-Muthanna governorate, southern Iraq. The selected water samples were taken from different sources of tap water and river samples from the Euphrates and collected from various locations: residential, agricultural, and industrial. Results: The mean values of Pb, Cd, and Ni in tap water samples are 3.76, 2.62, and 84.88 μg/L, respectively, while the corresponding element levels in river water are 11.21, 7.58, and 104.31 μg/L, respectively. Rivers water samples recorded higher levels of toxic metals than tap water samples. Concentrations of toxic elements in water samples from industrial locations of Al-Muthanna governorate are higher than in the agricultural and residential places. Toxic metals in water samples can be arranged in the following sequence: Ni > Pb > Cd. Conclusion: The levels of heavy metals in most water samples were above the permissible levels according to USEPA; therefore, it is recommended that the water samples should be regularly monitored for heavy metals to prevent the effect of heavy metals contamination in the human food chain.

Water quality assessment in the Moulouya Estuary (Northeastern Morocco): The effect of wastewater on microbiological and physicochemical properties

The study concerns the Moulouya Estuary River, the second-longest African river that flows into the Mediterranean Sea, to evaluate the impact of wastewater discharges on water quality regarding its physicochemical and microbiological composition. The results showed that most studied parameters were influenced by seasonal variation and changed significantly from upstream to downstream (p < 0.05). The mean values of water temperature (22.5°C), pH (8.4), dissolved oxygen (6.7 mg/l), orthophosphate (0.03 mg/l), biological oxygen demand (5.9 mg/l), nitrates (10.12 mg/l), total suspended solids (89.75 mg/l), copper (7.8 µg/l), fecal streptococci (36 CFU/100 ml), fecal coliforms (81.5 CFU/100 ml), and total coliforms (179.5), conforms with the recommended surface water quality limits indicating excellent to good quality, except for, electrical conductivity (31618 µs/cm), sulfate (1049 mg/l), lead (116.67 µg/l), and cadmium (5.09 µg/l) indicating poor surface water quality. The mean values of Pb, Cu, and Cd exceed the limits values recommended for aquatic life. The water quality index (CCMEWQI) represents the overall quality, showing that the river studied is frequently threatened, and the conditions often deviate from desirable levels for aquatic life. The pollution index (PI) indicates that the water of Moulouya Estuary is slightly affected by Pb. However, the Metal Index (MI) indicates a significant environmental risk. Furthermore, a gradient of the Metal Pollution Index (MPI) was recorded in studied sites following the order: S2>S3>S4>S1. Although the study area does not present a significant microbial contamination problem, heavy metals and high-water mineralization are major concerns. These factors can have adverse effects on aquatic organisms and ecosystems, requiring attention and appropriate management measures to limit their impact.

Wild Boar (Sus scrofa L.) as the Biomonitor of Cadmium and Lead Pollution in the Republic of North Macedonia

Until the outbreak of African swine fever in almost the entire Europe and consequently in the Republic of North Macedonia (2022), the population of wild boars was in increase. The biological characteristics of this species make it suitable to be used as a bioindicator for environmental pollution. The concentrations of cadmium and lead (Cd and Pb) were measured using atomic absorption spectrophotometry in the liver of free ranging wild boars. Samples were taken from 608 animals, harvested in a period of 7 years (2016-2022), in 11 hunting locations that cover the whole territory of the Republic of North Macedonia. The mean value of Pb in the liver in all hunting areas was 0.225 mg·kg-1 wet weight with range of 0.154-0.722 mg·kg-1, while mean Cd was 0.366 mg·kg-1 and ranged from 0.177 to 0.464 mg·kg-1. A statistically significant difference in Cd was found between the hunting locations, while Pb differed between hunting years. The mean Cd concentrations were significantly higher in Pelagonisko, Krivorečansko and Ohridsko-Prespansko hunting areas than in those from Pološko hunting area, while the mean Pb values in 2019 and 2020 were significantly higher than the mean value determined in 2021. For Cd, 18.2% of the total number of samples exceeds the maximum allowed limit provided in the legislation, while for Pb it was 6.7%. The maximum mean value for Pb (0.336 mg·kg-1) was measured in 2020 and for Cd (0.449 mg·kg-1) in 2016. The mean values for Pb and Cd obtained in this study were in line with data reported for wild boar from other European countries.

Environmental Assessment of Soils and Crops Based on Heavy Metal Risk Analysis in Southeastern China

Heavy metal pollution in soil–crop systems has attracted great attention globally, caused by rapid urbanization and intensive industrialization. The research aims to investigate the environmental quality of the agricultural production area in Taizhou City, a typical economic region that is along the Yangtze River in the Southeast of China. A total of 370 sampling sites were chosen, with 370 soil, rice (Oryza sativa L.) and wheat (Triticum aestivum L.) samples collected, respectively, for measuring and analyzing the status, spatial distribution and pollution level of different heavy metals. The mean values of soil Cr, Pb, Cd, As and Hg were 66.78, 32.88, 0.23, 8.16 and 0.16 mg/kg, which were lower than the risk control standard values (RCV). However, the mean values of Pb, Cd and Hg were 1.25-, 1.77- and 2-fold larger than their soil background values (SBV) due to the intensive anthropogenic activities. The average content of Cd in rice exceeded its food safety limiting values (FCV) by 0.05 mg/kg, and the average contents of Pb in rice and wheat both exceeded the relevant FSV by 0.42 and 0.186 mg/kg, respectively. In addition, the maximum As and Cr contents in rice and wheat could be 0.13, 0.46 mg/kg and 0.63, 3.5 mg/kg larger than the relative FCVs in certain areas. Most of the high-value areas of soil and crop heavy metals were mainly located in Xinghua City, Taixing City and Jiangyan District, which had a similar distribution pattern with local industries or anthropogenic activities. The heavy metal pollution in soils and crops was found to be inconsistent, as 8.94% of the arable land possessed lightly metal pollution, while 3.18% of the area of rice and 4.0% of the area of wheat suffered severe pollution, with excessive accumulation of Cr, Pb and Cd. Based on the heavy metal pollution assessment of soil–crop systems, approximately 83% of the study area possessed medium or higher environmental quality, which was preferable for agricultural production. Our results implied that the spatial distribution and pollution level of the heavy metals in soil–crop systems were significantly influenced by industrial activities, followed by agricultural sources, transportation emissions and so on. Therefore, continuous monitoring and source control of heavy metals, especially for Cr, Pb and Cd, should be conducted to ensure the regional environmental quality and food security.

Evaluation of the Smoking Factor in the Blood of Workers in Diyala State Company and its Relationship to Heavy Metals (Lead, Nickel and Copper)

Environmental pollution of heavy metals is becoming an increasing problem and has become a major concern due to the adverse effects it causes worldwide. Heavy metals are naturally occurring elements that have a high atomic weight and a density at least five times greater than water. It’s a multiple industrial, domestic, agricultural, medical and technological applications have led to its widespread use in the environment; Raising concerns about their potential effects on human health and the environment. The aim of the current study is Evaluation the relationship between the smoking factor in the blood of workers in Diyala State Company and to the percentage of the heavy metals such as lead (Pb), nickel (Ni) and copper (Cu) . This study was conducted for the period from 1/10/2021 to 1/3/2022, Eighty two blood samples were collected (58 blood samples from workers working in the Diyala State Company affiliated to the Ministry of Industry and Minerals, while, 24 control samples were from control samples for employees who don’t working with industrial emissions).The workers were divided into three groups based on the location work inside the station, sector (A) represented painter workers, sector (B) characterized the workers specialized in the copper coil of the electrical transformer, while sector (C) represented the iron core section of the electrical transformer. Five ml. of venous blood was taken for each sample. The concentration of Pb, Ni and Cu in the blood samples were determined by using the Flameless Atomic Absorption Spectrometer (FLAAS). The results of the intensive study showed the presence of high levels of lead, nickel and copper in smokers and non-smokers workers within the profession compared to control samples during the service period, with significant differences (P < 0.05). The results showed increasing levels of lead, nickel and copper with the progression of the service life, and the elements (lead, nickel and copper) recorded the highest average during the service period of 21-34, The painting worker showed high level of Ni while, Cu level peaked in wires worker . Based on age periods, elements levels (Pb, Ni, and Cu) were increased with age period progression, where it is found the levels of Pb, Ni, and Cu scored highest mean within >50 age period, while the least mean value of Pb, and Cu at 3-40 years age period, and least mean value of Ni was at <30 age. Finally, the results discovered there is positive correlations among metals and worker’s age.

The Concentration of Heavy Metals in the Sediments of the River Nun Estuary, Around Akassa, Niger Delta, Nigeria

Levels of the heavy metals lead (Pb), cadmium (Cd), nickel (Ni), zinc (Zn), and manganese (Mn) were analyzed in the sediments of the River Nun estuary. This was done in order gauge the impact of anthropogenic inputs such as pesticides, fertilizers, oil spillage and other industrial and anthropogenic wastes disposal, especially at the coastal parts of the region on bottom sediments. Three sampling Stations were chosen for the purpose of this research. Station 1 (Buo-Ama Creek) was established close to the entrance of Buo-Ama creek, in the Nun River estuary. Station 2 (Erewei- Kongho) was established along one of the tributaries of the Nun River estuary around Erewei- Kongho. Station 3 was established in Ogbokiri. Sediment samples were collected with the aid of a soil auger and a galvanized metal core cylinder from the three (3) sampling stations along a transect running from the low intertidal level (LIL), through the mid intertidal level (MIL) to the high intertidal level (HIL). Sediment samples were analysed in the laboratory using the method of Atomic Absorption Spectrophotometer (AAS). Means and standard deviations were calculated for all the measured parameters. A one-way ANOVA was employed at the 95% confidence limit to test for differences across stations in the heavy metals. Turkey HSD post HOC test was also employed to separate means and identify where variability and similarities exist. This was aided by the SPSS 20.0 statistical tool kit. The result shows that Pb has the highest concentration, followed by Zn, Ni, Cd, and Mn respectively. The lowest values of all metals were observed at station 2, while the highest concentrations of metals were recorded at sampling stations 1. The results show that the value of Pb was highest in station 1(1.347±0.001), followed by Station 3 (1.24±0.001). Station 2 had the least mean value of Pb (0.884±0.001). Cd showed similar patterns across the three sampling stations 1, 2 and 3, with the values 0.068±0.002, 0.046±0.001, and 0.054±0.002 respectively. Ni also presented slight difference across the three sampling stations. Concentration of Zn were higher in station 1 and 2 (1.265±0.002 and 1.038±0.002), than in station 3 (0.725±0.001). All metal concentration was however lower than the international permissible limited. The concentrations of Mn were also observed to present a similar pattern across the sampling stations. There is a significant difference (P&lt;0.05) in all heavy metal parameters across all stations. Heavy Metal Concentrations were found to decrease with increasing distance from the river mouth, suggesting that anthropogenic inputs, related to agricultural and domestic discharge into the river, are the major sources of heavy metals in the river sediments. Land based activities therefore have a profound effect on aquatic ecosystem stability and health.

Evaluation of the water quality of borehole water from a partially remediated oil spill site in Ikot Ada Udo, Akwa Ibom State, South–South Nigeria

The quality of borehole water from Ikot Ada Udo was studied. Borehole water ( n = 48 ) samples were aseptically collected for 1 year. Samples were collected from 3 boreholes (BH 1, BH 2, BH 3) which were 500, 800, and 1000 meters respectively from the Ibibio 1 capped oil well. Control samples were collected 10,000 meters (Ibagwa, Abak) from the study site. Produced water ( n = 3 ) was also collected. Samples were analyzed for lead (Pb), cadmium (Cd), nickel (Ni), chromium (Cr), iron (Fe), vanadium (V), cobalt (Co), arsenic (As), manganese (Mn) using an inductively coupled plasma optical emission spectrometer; for total petroleum hydrocarbon (TPH) using Agilent 6890N Flame Ionization Detector Gas chromatography; for physico-chemical parameters using their respective equipment and methods. The heavy metals, TPH, and physico-chemical parameters levels varied between boreholes of the study site. The mean heavy metals, physico-chemical parameters (except pH, DO, temperature), and TPH levels of the borehole water from the study site were higher compared to the control. The mean values of Pb, Cd, Cr, and Fe in boreholes were above WHO and NSDWQ acceptable standards for drinking water. The contaminants in the borehole water were potentially introduced by produced water. Water quality index values of boreholes 1 and 3 is not an indication of good water quality. The study revealed unacceptable levels of some contaminants in the borehole water. A thorough clean-up of the spill site is therefore recommended for the total restoration of the aquifer and environment back to normal. • The 2007 spillage led to the release of crude oil into Ikot Ada Udo farmlands.. • Despite the remediation excercise in 2008, recent studies indicate that the site is still contaminated. • No study exist on the water quality of boreholes from the study site. • Borehole water from the study site is contaminated with Pb, Cd, Cr and Fe. • Water quality index revealed poor water quality for boreholes 1 and 3.

Effects of mining activities on the distribution, controlling factors, and sources of metals in soils from the Xikuangshan South Mine, Hunan Province.

In this study, we analyzed 53 topsoil samples from the Xikuangshan South Mine in Hunan Province to investigate the distribution characteristics of pH and the concentrations of selected metals to determine the controlling factors and identify their sources. Kriging interpolation, correlation analysis, principal component analysis, the index of the geoaccumulation index, and Hakanson's potential ecological risk were applied. The results show that the mean values of Pb, As, Cd, and Sb in the study area were larger than the background value of mountain soil in Hunan Province, and only the average Cr concentration was slightly lower than the background value. The spatial distributions of pH and five metals in the soil were very different, indicating that pH had no significant effect on the distribution of the metals. The wind, rivers, and land-use patterns in different regions of the study area may be the main reasons for their distribution patterns. The correlation component and principal component analysis revealed that Pb showed positive correlations with Cr and Cd, respectively, and Sb-As and Cr-Cd showed strong paired correlations. The cumulative proportion of the first two components accounted for 70.516% of the total variance, which suggests that mining activities are a major source of As and Sb, whereas Pb, Cr, and Cd were derived from natural and anthropogenic sources. The geoaccumulation index revealed that the major pollutants in the soils were mainly Cd, followed by Sb and As. The soils in the study area were moderately contaminated with Pb and lightly polluted by Cr. The ecological hazards of each metal in descending order were Cd > Sb > As > Pb > Cr. The index of the comprehensive potential ecological risk for metals indicated that the Xikuangshan South Mine is at or above a moderate ecological risk level, with an extremely strong potential for ecological risks posed by Cd and Sb. Integr Environ Assess Manag 2022;18:748-756. © 2021 SETAC.

COMPARATIVE ANALYSIS OF SOME HEAVY METALS LEVELS IN LEAVES, PEELS AND TUBERS OF CASSAVA PLANTED ALONG EAST-WEST ROAD RIVERS STATE

Introduction: Pollution of the environment by heavy metals has caused serious environmental problems, which threatens the existence of various ecological system, agriculture and human health. This study assessed the comparative analysis of some heavy metals levels in leaves, peels and tubers of cassava planted along East-West Road Rivers State.&#x0D; Materials/Methods: Cassava leaves and tubers samples were collected from farmlands along East-West road (SX, SY and SZ communities, in Emohua, Tai, and Ahoada West LGA respectively), Rivers state, Nigeria. The samples were monitored for heavy metals levels to assess the impact of automobiles on cassava peels, leaves and tubers using Solar Thermo Elementary Atomic Absorption Spectrometer, ModelSG 71906. Metals studied were Lead (Pb), Nickel (Ni), Chromium (Cr), Cadmium (Cd), and Arsenic (As).&#x0D; Results: The mean concentration of Ni present in leaf was 2.81±0.104 mg/kg, tubers recorded 2.23±0.073 mg/kg and peels 3.20±0.06 mg/kg. The highest concentration (4.064±0.035 mg/kg) of Ni was observed in peels while the least concentration (1.80±1.023 mg/kg) was recorded in the tubers. The mean values of Pb in leaves, tubers and peels were 2.22±1.023 mg/kg, 1.80±1.023 mg/kg and 2.64±0.32, highest concentration was recorded in tubers. Arsenic values were 0.16±0.020 mg/kg &gt; 0.51±0.021 mg/kg &gt; 0.38±0.203 mg/kg in peels, tubers and leaves respectively. The values of As were above WHO safe limit of 0.1mg/kg. Also, the mean values of cadmium in leaves, tubers and peels were 0.054±0.570 mg/kg, 0.046±0.057 mg/kg and 0.16±0.609 mg/kg respectively. The highest concentration (0.138±0.109 mg/kg) was in the tubers. Finally, chromium was found to be present in all the cassava samples (leaves, peels and tubers). The mean concentration of chromium (Cr) was 3.58±0.023 mg/kg, 2.76±0.005 mg/kg and 3.83±0.203 mg/kg in leaves, tubers and peels respectively.&#x0D; Conclusion: From the findings, heavy metals were found in the samples and thus, crops should be cultivated far away from major roads.

Water Quality Assessment of Elechi Creek Receiving Effluent Discharges from Industrial Activities in Port Harcourt, Nigeria

The Physico-chemistry and heavy metal analyses of Elechi creek were assessed to determine the level of contamination and concentration of metals in the water body. Standard analytical procedures were used during the study. The study showed that pH recorded 7.00-7.35 in surface water; 6.60-7.00 in wastewater while Temperature of the surface water samples ranged from 27.9-29.0°C, Wastewater samples also recorded temperatures values of 26.9-27.8°C in all sampled stations. The values of metals in the surface water ranged from 0.14 to 0.26 mg l-1 for Fe, 0.04 to 0.09 mg l-1 for Cu and 1.21 to 1.42 mg l-1 for Zn. The mean values for Pb, Cr, Mn and Cd were 0.001 mg l-1 in all the stations. The mean values in the wastewater samples ranged from 7.25 to 16.62 mg l-1 for Fe, 4.70 to 8.50 mg l-1 for Zn, 0.21 to 0.34 mg l-1 for Mn, 0.13 to 0.22 mg l-1 for Cr, 0.06 to 0.12 mg l-1 for Pb, 0.03 to 0.07 mg l-1 for Cu and 0.001 mg l-1 for Cd. There were no significant differences across the sampled stations; although some of the metals were below permissible limits. The study revealed that the water is heavily polluted but not contaminated with the waste products it receives, although the accumulated presence of these pollutants in the water can pose an environmental threat in the near future.

Critical risk analysis of metals toxicity in wastewater irrigated soil and crops: a study of a semi-arid developing region

Toxic elemental exposure through consumption of contaminated crops is becoming a serious concern for human health. Present study is based on the environment and health risk assessment of wastewater irrigated soil and crops in a semi-arid region Faisalabad, Pakistan. The concentrations of potentially toxic elements (Cu, Cr, Mn, Fe, Pb, Zn, Ni) were analysed by atomic absorption spectrometer in five different crops (Corn, rice, wheat, sugarcane and millet), while, their topsoil’s and multi targeted risks analysis were assessed. Results showed, the mean values of Pb and Zn were higher in crop than Food and Agriculture Organization guidelines for food additives and contaminants. A strong positive correlation was found among wastewater and crop’s toxic metals (r2 values in Cu, Zn, Pb, Ni and Cr were 0.913, 0.804, 0.752, 0.694, 0.587 respectively). Whereas, a strong correlation was also found among soil and wastewater lead (r2 = 0.639). The calculations of Nemerow Integrated Pollution Index (NIPI) showed the soil samples maximum pollution limit (NIPI > 3) and Potential Ecological Risk Index (PERI) was found to be higher than maximum limit (PERI > 600) for all samples. While, for non-carcinogenic risk, Hazard Index (HI) values in adult were near threshold (HI > 1) for all crop samples. In children, the HI values for Corn, Rice and Wheat were above threshold limit and for Sugarcane and Millet, these were near to threshold. Cancer risk values for Cr found higher than safe limit (1 × 10–6) in adult and children for crop samples. Crop irrigation by wastewater irrigation is a prominent alternative option for water scarce countries, however prior testing and treatment of such wastewater streams must be employed to minimize the adverse impacts on human health and environment.

Factors associated with lead (Pb) exposure on dogs around a Pb mining area, Kabwe, Zambia

Lead (Pb)-poisoning is a serious public health concern and dogs have been useful as a sentinel-animal for Pb exposure of humans. In the present study, the blood Pb concentrations (BLC), isotope ratios (208 Pb/206 Pb and 207 Pb/206 Pb), and biochemistry of 120 domestically owned dogs living around a Pb mining area, in Kabwe, Zambia were analyzed to determine factors associated with Pb exposure. The overall mean value of Pb in dog blood in the present study was 271.6 μg/L. The BLC in the dogs from sites near the mine were significantly higher than those in the dogs from a site 4 km from the mine (352.9 ± 205.1 μg/L versus 28.0 ± 13.9 μg/L). BLC significantly decreased with both increasing age of the dogs and distance from the mine. The Pb isotope ratios in the dog that resided near the mine showed values similar to those reported at the galena mine in Kabwe, which is considered to be the source of Pb exposure. In contrast to the high metal exposure that was determined in these dogs, the mean values of most analyzed parameters in the blood biochemical analysis were surprisingly within or close to the standard reference values. Moreover, none of the dogs showed overt signs of Pb-poisoning or other clinical symptoms. The results of analysis of Pb exposure of the dogs obtained in the present study, which are similar to the previously reported results in human in this location, suggest that dogs could be useful as a sentinel animal for Pb exposure of humans in Kabwe.

Physico-Chemical Properties of Soil Sourced from Automobile Mechanic Workshop in Ikoku Mechanic Village, Mile 3 Diobu, Port Harcourt, Rivers State, Nigeria

This study investigated the impacts of automobile mechanic workshops on the concentrations of PAHs, T.H.C, T.O.C, pH, EC, Cations, heavy metal and particle size distribution in urban soil sourced from automobile workshops in Ikoku mechanic village, Mile 3 Diobu, Port Harcourt, Rivers state. Six samples were collected at sites of close proximity to the selected automobile workshops (Experimental sites) and sites that are far away from the workshop without the influence of automobile mechanic activities (control sites). The levels of Zinc (Zn), lead (Pb), Chromium (Cr) and cadmium (Cd) were determined using atomic absorption spectrophotometer (AAS), the PAHs were determined using GC-FID and GC-MS. The levels of T.O.C and T.H.C were determined using Titration method and Genesis 10 UV spectrometer, the pH and EC were determined using Pre-calibrated pH and EC meters, the Particle Size Distribution was determined by Sieve analysis method. Data interpretation involved the use of descriptive statistics for test of significant variation in the levels of heavy metals, Physico-chemicals and PAHs between the experimental sites and control site. Findings revealed that concentrations of Heavy metals, PAHs, T.H.C, T.O.C, EC and Cations were generally higher in soils under the influence of automobile mechanic workshop activities than sites with no such influence. The mean values of Pb, Zn, Cr and Cd were 32.94, 74.17, 5.35 and 2.86mg/kg respectively in soils under the influence of automobile mechanic activities and 32.52, 100.69, 10.09 and 3.68mg/kg respectively in soils with no such influence. The mean concentrations of PAHs, T.H.C, T.O.C, EC, pH and Cations as compared to those of the Control sites are 332.35 to 65.28, 2.47 to 1.94, 36.20 to 22.35, 273.2 to 119.7, 7.145 to 7.245 and 30.52 to 42.99 respectively. There were significant variations in the levels of PAHs, Heavy metals and the Physico- chemical parameters between the experimental sites and the control sites. The Particle Size Distribution revealed that the soil is of low permeability thus limiting the degree of seepage and supporting more accumulation of the contaminants at the top soil. It is recommended that mechanic villages should be sited far from residential areas, Quick remediation of polluted soil using various remediation methods should be encouraged and continuous education and training should be provided for the automobile workers, emphasizing on the environmental implications of their poor occupational waste management.

Heavy metals concentrations in selected soil samples of Al-Diwaniyah governorate, Southern Iraq

Heavy metals’ origin, accumulation, and distribution in soil samples have been the focus of much attention by many researchers to monitor soil pollution. The objective of this study is to determine the levels of the heavy metals such as lead (Pb), cadmium (Cd), copper (Cu), and zinc (Zn) in the soil samples collected from different areas residential, industrial and agricultural of Al-Diwaniyah governorate southern Iraq using the effective technique of atomic absorption spectroscopy AAS, so that the degree of pollution could be ascertained. The results show that the mean values of Pb, Cd, Cu and Zn concentrations in soil samples are 31.75, 1.804, 18.51 and 29.82 mg/l, respectively. The results show that the heavy metals concentrations were found to be higher in industrial regions than the other locations. Mean values of Pb and Cd in soils studied were generally higher than the acceptable limits, suggesting some degrees of pollution with heavy metals.

Levels, Distributions and Health Risk Assessment of Lead, Cadmium and Arsenic Found in Drinking Groundwater of Dehgolan’s Villages, Iran

Water contamination by heavy metals has become a serious environmental issue due to its serious threat to human health. The current research was conducted to determine heavy metal concentrations in drinking groundwater samples in villages of Dehgolan, western Iran and to ascertain the potential health risk in terms of estimated non-carcinogenic risks by hazard quotient and hazard index and carcinogenic risk to the residents living in these areas from exposure to the metals via drinking water ingestion and skin contact routes. Health risks were conducted for resident adults based on the USEPA health risk assessment guidelines. The mean values of Pb, Cd, and As in the groundwater samples were 0.0026 mg/L (ranging from 0.0020–0.0030 mg/L), 0.0009 mg/L (ranging from 0.0007–0.0010 mg/L), and 0.0068 mg/L (ranging from 0.0011–0.0360 mg/L), respectively. Compared to the WHO drinking water guidelines for Pb, Cd and As, virtually all the trace elements in the drinking water of villages in the present study could meet the requirements of the regulation except As in some villages. The results of the study obtained in all cases demonstrated that the non-carcinogenic risk was below the safe limit. The calculated carcinogenic risk for adults obtained was all lower than USEPA’s acceptable cancer risk range of 1 × 10−4 to 1 × 10−6, suggesting no potential carcinogenic risk from drinking water consumption.

Comparison of heavy metals in fresh and used engine oil

Used oil considered as a threat to the environment due to presence of hazardous substances. Three brands of engine oil; Total QUARTZ, Carient ULTRA and Shell ADVANCE were taken to compare the heavy metal contents in fresh and used engine oil. Used oil was taken from bikes, cars and public transport. Atomic Absorption Spectrophotometer was used to determine the heavy metal contents. The mean values of Pb, Cu, Cr, Ni and Fe in fresh oil samples ranged from 7.17–9.83, 3.58–3.83, 1.91–20.58, 1.42–3.83, 46.83–108.58 while their used oil metal concentration ranged from 8.58–12.67, 4.33–143.33, 5.75–55.41, 2.17–15.83, 70.75–332.75 ppm respectively.

Large scale study of the within and between spatial variability of lead, arsenic, and cadmium contamination of cow milk in China

This large scale study investigated the spatial variability of Pb, As, and Cd contents in raw milk within and between the 10 main milk producing areas in China. A total of 997 raw milk samples were analysed by inductively coupled plasma mass spectrometry (ICP-MS). Mean values of Pb, As, and Cd in milk were 1.75 μg/L, 0.31 μg/L, and 0.05 μg/L, respectively. The highest level of Pb and As was present in area C, and Cd was highest in area J. The standard deviation suggested a higher heterogeneity of milk heavy metal contamination within area than between areas. Levels of Pb, As, and Cd showed significant differences between studied areas. The estimated root mean squared standardised error obtained by the cross-validation suggested a differentiated quality of Pb, As, and Cd modelling between areas: the predictions obtained were sometimes overestimated or underestimated. These results can be used to define a more appropriate sampling procedure for heavy metal contaminate distribution in raw milk for improved future control of milk contamination by heavy metals in the studied areas. The significant positive correlations between concentrations of Pb-Cd, As-Cd, and Pb-As were observed in nine, six and five areas, respectively. No significant negative correlations were observed. The observed variability of correlation values suggested a different pollution source for Pb, As, and Cd in milk between areas. Further studies are required to clarify the relationships between the contamination of raw milk by heavy metals and the herd environment.

Concentration and exposure assessments of cadmium and lead in pumpkin, sunflower, watermelon, and jabooni seeds collected in Iran

Introduction â�� Heavy metals such as lead (Pb) and cadmium (Cd) are known to have high human toxicity. Their presence at various rates in oilseeds has gained more importance during the last few years in the absence of regulation in seeds. The consumption of seeds has been recently reported to increase in Iran, especially among adolescents and young people, so that heavy metal contamination in these seeds could become a great problem of public health. Materials and methods â�� This study investigated the Cd and Pb levels present in 168 seed samples (pumpkin, sunflower, watermelon and jabooni seeds) collected over the country, using graphite furnace atomic absorption spectrometry after microwave digestion. The data were used to estimate the weekly intake of Cd and Pb in Iranian consumers. Results and discussion â�� The highest concentrations of Pb and Cd were found in pumpkin shells and sunflower kernels, respectively. The concentrations of Pb and Cd detected in the seed samples averaged 77±28 I¼g kg-1 and 264±177 I¼g kg-1, respectively. The Pb content in 39 seed samples was exceeding the limit of 100 I¼g kg-1 established by the Joint FAO/WHO Expert Committee on Food Additives (JECFA). The seeds with the highest Pb contamination were pumpkin seeds (67), followed by sunflower (30), watermelon (25), and jabooni seeds (15). None of the watermelon and jabooni seed samples were contaminated with Cd. The highest concentration (731 I¼g kg-1) and the highest number of samples (35) contaminated with Cd were recorded in the sunflower seeds. The differences in mean value of Pb and Cd among the seeds collected in various Iranian cities were not found statistically significant. Similarly, the mean intake of Pb and Cd estimated from the seed samples was much lower than the tolerable weekly intake (25.0 and 2.5 µg kg-1 week-1 for Pb and Cd, respectively) estimated by the JECFA. Conclusion â�� Although the mean dietary exposure of cadmium and lead was much lower than the reference doses, the high incidence of Pb and Cd in widely consumed oilseeds in Iran, and the toxic effects of Pb and Cd, indicate the necessity for regular surveillance to reduce intake of heavy metals by Iranian population. © ISHS 2018.

Pollution assessment and source apportionment of arsenic, lead and copper in selected soils of Khuzestan Province, southwestern Iran

Due to the intensified industrial activities and excessive application of agrochemicals and organic waste materials over the last few decades, there is a great concern about the accumulation of potentially toxic elements (PTEs) in soils from north of Khuzestan Province, southwestern Iran. Therefore, a comparative study with a total number of 300 composite soil samples (0–10 cm) from industrial, urban, agricultural, forest, and rangelands; and 26 samples from the major types of soils parent materials was conducted to examine sources, pollution status, and the effects of soil properties, land use types, and the local lithology on the total concentrations of As, Pb, and Cu (measured using atomic absorption spectrometer (AAS) equipped with graphite furnace) in the soils studied. The mean values of Pb and Cu were 12.2 ± 4.6 and 13.5 ± 7.6 mg kg−1, respectively, slightly higher than the background values of the study area, but lower than the guideline values of Iranian Environmental Quality Standard for Soils. However, the mean values of As (1.72 ± 1.15 mg kg−1) were lower than both background values and the guideline values of Iranian Environmental Quality Standard for soils. The greatest values of the geo-accumulation index (I geo), enrichment factor (EF), and the concentrations of Pb, Cu, and As were arranged as industrial > urban > agriculture > rangelands = forest land uses. The results also indicated that concentrations of all PTEs were greater in soils as compared to those in parent materials. Using principal component analysis (PCA), the origin of Cu and Pb with moderate to high enrichments was attributed to the inputs from both natural and anthropogenic sources. However, As was found to be mainly influenced by lithogenic origin.