Lead Concentrations In Samples Research Articles

Influence of lead concentration on Debye temperature in palladium alloys and microstructure

This article is about palladium-based membrane alloys with promising characteristics. Lead concentration in samples is 5 and 20 wt%. The samples are prepared from high purity metals (99.95 wt%). The samples are characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM) and atomic force microscopy (AFM) techniques. Effect of the concentration of alloying components on the Debye temperature and on the mean-square displacements of atoms is determined. Influence of defects of the first class (point defect – vacancy pairs, pores, dislocation loops of small radius) found to be dominant in alloys.

Control by the accuracy of the results of studies for the lead content in samples applying the microwave laboratory system PLP-01M

The article presents the analysis of the study results of samples for lead content by their determination on the atomic absorption spectrometer “Kvant-2AT”, taking into account the use of the microwave laboratory system PLP-01M and while the sample preparation in accordance with GOST 26929 “Raw materials and food product. Sample preparation. Mineralization to determine the content of toxic elements”. A fundamentally new method of the sample preparation is used in the microwave laboratory system PLP-01M. The decomposition was carried out in a closed system, i.e. sealed fluoroplastic vessels under the influence of high temperature, pressure and microwave field. The microwave field was created by a special generator-magnetron in the operating chamber of the furnace. According to the assessment results of the operational control of the measurement procedure applying samples for the lead control when the microwave laboratory system PLP-01M was introduced in the laboratory; the analysis procedure was found satisfactory.

Lead in breastmilk samples from women living in the West Bank: a cross-sectional study

BackgroundBreastmilk is the recommended form of enteral nutrition for all infants. Infants nourishing on breastmilk contaminated with lead are at high risk of exposure to this neurotoxic heavy metal. The aim of this study was to screen lead concentrations in samples of breastmilk obtained from women living in three main regions of the West Bank and to investigate the sociodemographic characteristics associated with high lead concentrations. MethodsIn this cross-sectional study, breastmilk samples were collected from breastfeeding women living in Nablus, Ramallah, and Jerusalem. The participants' sociodemographic characteristics were recorded, and the lead concentration in breastmilk samples were quantified using a graphite furnace atomic absorption spectrophotometer. Ethical approval was obtained from the Institutional Review Board of An-Najah National University, and all participants provided written informed consent. FindingsBreastmilk samples were obtained from 89 women. The median lead concentration was 4 μg/L (range 2–12 μg/L). The lead concentration was higher than WHO's safety limits for occupationally unexposed population in 17 (19%) samples. Lead concentrations were also significantly higher in samples obtained from women living in refugee camps and cities (p=0·003) than in women living in villages, higher in women with low monthly household income than in women with high monthly household (p=0·020), higher in women living in houses with peeling paint than in women living in houses with no peeling paint (p=0·026), higher in women who worked in agriculture for more than 3 years than in women who worked in agriculture for less than 3 years or less (p=0·005), and higher in women who frequently used eye kohl than in women who did not (p=0·004). Multiple linear regression analysis showed that using eye kohl was a significant predictor (p=0·040) of lead concentration in breastmilk above WHO's safety limits. InterpretationIn this study, about one-fifth of women had concentrations of lead in their breastmilk above the WHO's safety limits. Authorities need to implement measures to eliminate or reduce lead exposure, especially in refugee camps and cities. Eye kohl preparations marketed in the occupied Palestinian territory should be screened for lead content. FundingNone.

Determination of lead at physiological level in human biological materials using the total reflection X‐ray fluorescence analysis

Total reflection X‐ray fluorescence (TXRF) analysis was applied in determination of low concentration of lead in samples of human biological materials. The determination of lead in human serum and hair samples is presented as an example. In serum samples, lead concentration was in the range from 0.013 to 0.051 μg/g (median 0.024 μg/g). The reference ranges of lead content in hair are from 1.41 to 4.08 μg/g for men and from 1.18 to 3.29 μg/g for women groups, respectively. Because of Pb concentration range close to the detection limit of the TXRF method, the measurement needed evaluation of the best analytical conditions. This paper presents the results of this evaluation, namely internal standard selection, measurement conditions, and quantitative calibration of the spectrometer. Finally, as a result of evaluation, the detection limit was found on the level 0.001 μg/g (water solution) and about 0.005 μg/g for human hair samples and 0.007 μg/g for serum samples. The obtained values reach nearly the physiological lead level. The presented results are of practical importance for lead concentration studies in human biological materials using the TXRF method. Copyright © 2016 John Wiley & Sons, Ltd.

Use of a Field Portable X-Ray Fluorescence Analyzer for Environmental Exposure Assessment of a Neighborhood in Cairo, Egypt Adjacent to the Site of a Former Secondary Lead Smelter

The objectives of this study are to demonstrate for the first time the use of a field portable X-Ray Fluorescence Analyzer (XRF) in a multi-media environmental survey and to use the survey results to determine if residual lead from a once-active secondary lead smelter in Cairo, Egypt, still posed a health risk to the residents when comparing results with US EPA standards. Results were analyzed to determine if relationships among the variables indicated that there were residual impacts of the former smelter. Samples collected inside and near a total of 194 dwellings were analyzed. The mean floor dust lead loading was 7.48 μg lead/ft2. Almost 10% of the dwellings had at least one floor dust wipe sample that exceeded the United States Environmental Protection Agency's (USEPA) interior settled dust lead level of 40 μg lead/ft2. The median paint lead level was 0.04 mg lead/cm2. 17% of the dwellings had at least one interior paint sample that exceeded the USEPA standard of 1.0 mg lead/cm2. Mean soil lead concentration in the study area was 458 ppm and 91 ppm outside the study area. Four of nine composite soil samples exceeded the US EPA limit for bare soil in play areas. Lead concentrations in samples collected in locations outside the study area did not exceed the limit. The highest concentration was in the plot closest to the smelter and may represent residual impact from the former smelter. Statistically significant relationships were not detected between interior floor dust lead loading and either interior paint lead loading or exterior dust lead concentration. Thus, no significant exposure from the former smelter was indicated by these analyses. This may have resulted from the time elapsed since the closing of the smelter and/or the relatively low paint lead levels. Further study is needed in other areas of Egypt near former and active lead smelters. Elevated levels of mercury and arsenic detected in soil samples do not appear to be related to the smelter but warrant further study.

Determination of Lead in fish, water and sediment

The objective of the study is to determine the concentration of Lead in water, sediment and the marine species, Indo-Pacific king mackerel popularly known as Spotted Seer fish (Scomberomorus Guttus) collected near seashore of Bay of Bengal from 5 locations (Pulicat, Ennore, Marina, Mahabalipuram and Kalpakkam) in North Chennai in 4 different seasons (Summer, Monsoon, Post-Monsoon, and Winter). The concentrations of Lead in each sample were determined using AAS method. Maximum concentrations of Lead in fish samples collected from different locations were 0.563 mg/kg (Pulicat Summer), 0.722 mg/kg (Ennore Summer), 0.616 mg/kg (Marina Monsoon), 0.363 mg/kg (Mahabalipuram Summer) and 0.673 mg/kg (Kalpakkam Post-Monsoon). Maximum concentration of Lead in water samples collected from different locations were 0.016 mg/l (PulicatSummer), 0.015 mg/l (EnnoreMonsoon), 0.012 mg/l (MarinaMonsoon and winter),0.014 mg/l (MahabalipuramMonsoon) and 0.016 mg/l (KalpakkamMonsoon). The maximum concentrations of Lead in sediments collected from different locations were 1.083 mg/kg (PulicatPostmonsoon), 1.481 mg/kg (EnnoreMonsoon), 0.848 mg/kg (MarinaSummer), 1.004 mg/kg (MahabalipuramSummer) and 0.904 mg/kg (KalpakkamPost-monsoon).

Consumption of lead-shot cervid meat and blood lead concentrations in a group of adult Norwegians

Several recent investigations have reported high concentrations of lead in samples of minced cervid meat. This paper describes findings from a Norwegian study performed in 2012 among 147 adults with a wide range of cervid game consumption. The main aim was to assess whether high consumption of lead-shot cervid meat is associated with increased concentration of lead in blood. A second aim was to investigate to what extent factors apart from game consumption explain observed variability in blood lead levels.Median (5 and 95 percentile) blood concentration of lead was 16.6µg/L (7.5 and 39µg/L). An optimal multivariate linear regression model for log-transformed blood lead indicated that cervid game meat consumption once a month or more was associated with approximately 31% increase in blood lead concentrations. The increase seemed to be mostly associated with consumption of minced cervid meat, particularly purchased minced meat. However, many participants with high and long-lasting game meat intake had low blood lead concentrations. Cervid meat together with number of bullet shots per year, years with game consumption, self-assembly of bullets, wine consumption and smoking jointly accounted for approximately 25% of the variation in blood lead concentrations, while age and sex accounted for 27% of the variance. Blood lead concentrations increased approximately 18% per decade of age, and men had on average 30% higher blood lead concentrations than women. Hunters who assembled their own ammunition had 52% higher blood lead concentrations than persons not making ammunition. In conjunction with minced cervid meat, wine intake was significantly associated with increased blood lead. Our results indicate that hunting practices such as use of lead-based ammunition, self-assembling of lead containing bullets and inclusion of lead-contaminated meat for mincing to a large extent determine the exposure to lead from cervid game consumption.

Peripheral neuropathy—lead astray?

fi lm showed basophilic stippling. Other investigations, including magnesium, zinc, and iron; auto, paraneoplastic, and anti-ganglioside antibodies; plasma electrophoresis, and Lyme serological tests, were normal or negative. Lead toxicity was diagnosed, and chelation therapy with succimer (2,3-dimercaptosuccinic acid) was given. Our patient’s drinking water came from a spring via an underground holding tank. A lead pipe supplied the water in the house from the holding tank. The lead concentrations in samples of water taken from the holding tank and kitchen were 0⋅3 μg/L and 2570 μg/L, respectively (current regulatory standard 25 μg/L). The water was unusually corrosive, with a pH of 6⋅1—giving it an increased potential to dissolve lead from the pipes. 2

Development of a simple method for the determination of lead in lipstick using alkaline solubilization and graphite furnace atomic absorption spectrometry

A simple method was developed for determining the total lead content in lipstick samples by graphite furnace atomic absorption spectrometry (GFAAS) after treatment with tetramethylammonium hydroxide (TMAH). Multivariate optimization was used to establish the optimal conditions of sample preparation. The graphite furnace heating program was optimized through pyrolysis and atomization curves. An aliquot containing approximately 50mg of the sample was mixed with TMAH and heated in a water bath at 60°C for 60min. Using Nb as the permanent modifier and Pd as the chemical modifier, the optimal temperatures were 900°C and 1800°C for pyrolysis and atomization, respectively. Under optimum conditions, the working range was from 1.73 to 50.0μgL−1, with detection and quantification limits of 0.20 and 0.34μgg−1, respectively. The precision was evaluated under conditions of repeatability and intermediate precision and showed standard deviations of 2.37%–4.61% and 4.93%–9.75%, respectively. The % recovery ranged from 96.2% to 109%, and no significant differences were found between the results obtained using the proposed method and the microwave decomposition method for real samples. Lead was detected in 21 tested lipstick samples; the lead content in these samples ranged from 0.27 to 4.54μgg−1.

Investigation of heavy metals (Cadmium, Lead) in Chironomidae and Gammarus pulex Namrood River – Tehran Province

Marine ecosystem pollution is one of the important problems of today environment. In this study the existence of heavy metal in the Namrood River, situated in Firoozkooh in Tehran province, Iran has been investigated. The Namrood River is located near Firoozkooh route, and is affected by pollutant from tourist centers, entertainment, gas stations, nearby villages' sewage systems, farming effluent, and hatchery farms. In some areas, its water is heavily polluted possibly by heavy metals. After selecting two stations in upstream and downstream of the river, they were sampled three times in both cold and hot seasons of year (mid-March, and June) for Chironomidae, and Gammarus plux sediments. The measured heavy metals were cadmium and lead. The results showed that the concentration of cadmium in measured samples varied from 0.010-0.2033 ppm. The concentration of lead in samples varied from 0.11-2.16 ppm. The results also indicated that sediments of samples taken from the upper station in the cold season had a higher proportion of cadmium and a higher concentration of lead than sediments in the lower station during the hot season.

Pb Detection in Soil Samples by Electroanalysis: Cyclic Voltammetry and Osteryoung Square Wave Stripping Voltammetry

Carbon Paste Electrodes (CPE) and Chemical Modified Electrodes (CMEs) are proposed as Pb sensors for soil samples treated with ammonium acetate. The extracted fraction were analyzed by electroanalytical techniques. The use of CPE and CMEs in conjunction with electroanalytical techniques as Cyclic Voltammetry (CV) and Anodic Stripping Voltammetry with Osteryoung Square Wave (OSWSV) showed to be very suitable to analyze the lead content in samples (under 10 ppm) of dangerous residues collected from a historically polluted site in Tijuana B.C., Mexico.

Environmental lead pollution and contamination in food around Lake Victoria, Kisumu, Kenya

Exposure to lead (Pb) through food, water, or contaminated air has adverse health impacts that are particularly severe in children. Many countries have outlawed the use of leaded petrol, and enacted policies and regulations limiting lead pollution, and lead levels in foods. However, African countries, including Kenya, have generally been slow in adopting policies and regulatory structures concerning lead pollution. The main objective of this study was to determine lead contamination levels in the environment around Kisumu (Kenya). Lead content in samples of tap water and other surface water ranged from 140 to 260, and 140 to 690 (μg/g), respectively. All the tap water samples had lead content above10 μg/g, the maximum WHO limit for lead in drinking water. The lead content in vegetables and fish ranged between 0.0 to 2.9 and 1.0 to 3.3 (μg/g), respectively. All the fish samples had lead levels above the WHO maximum limit of 0.2 (μg/g). Lead content in soil samples ranged from 0.2 to 3.9 (μg/g). These results indicate that there is considerable risk of lead poisoning from drinking water and eating some foods from these sites. Key words : Lead, pollution, environment, food safety.

Lead contents in the surface enamel of deciduous teeth sampled in vivo from children in uncontaminated and in lead-contaminated areas

This study aimed to: (1) measure lead contents in the surface enamel of two populations consisting of 4–6-year-old children, one from an apparently uncontaminated area (Ribeirão Preto, São Paulo State, SP, Brazil, n=247) and the other from an area notoriously contaminated with lead (Bauru, São Paulo State, Brazil, n=26); (2) compare biopsy depths between the two populations; (3) correlate biopsy depth with lead content; (4) stratify samples according to biopsy depth to compare lead contents in samples from similar biopsy depths. A surface enamel acid-etch microbiopsy was performed in vivo on a single upper deciduous incisor for each sample. Lead was measured by graphite furnace atomic absorption spectrometry (GFAAS) while phosphorus was measured colorimetrically to establish biopsy depth. Samples from both populations were classified into categories of similar biopsy depths based on biopsy depth quartiles. Median lead contents were statistically different between the Ribeirão Preto population (206 μg/g, range: 5–1399 μg/g) and the Bauru population (786 μg/g, range: 320–4711 μg/g) ( p<0.001); however, biopsy depth did not differ between the Ribeirão Preto (3.9 μm, Standard Deviation, SD=0.9) and Bauru (3.8 μm, SD=0.9) populations ( p=0.7940). Pearson's correlation coefficient for biopsy depths versus log 10 lead values was −0.29 for Ribeirão Preto and −0.18 for Bauru. Lead contents were statistically different between the two populations for all quartiles of biopsy depth. These findings suggest that lead accumulated in the surface enamel of deciduous teeth is linked to the environment in which people reside, indicating that this tissue should be further explored as an accessible biomarker of lead exposure.

Detection of lead-induced oxidative stress in the rat epididymis by chemiluminescence

It has been shown that lead (Pb) is able to induce lipid peroxidation, one of the main manifestations of oxidative stress. In this study we examined the relationship between chronic Pb exposure and level of reactive oxygen species (ROS) in reproductive system tissues of sexually mature male Wistar rats. One group of animals (control, K) was allowed to drink distilled water, the second group (Pb) was allowed to drink freely 1% aqueous solution of lead acetate. Another groups had a following supplements: rats were allowed to drink distilled water containing vitamin C (vit C) at concentration of 500 mg/l or Trolox (a vitamin E analog) at concentration of 48 mg/l or vit C (500 mg/l) + Trolox (48 mg/l). The similar groups among Pb-treated animals were examined after treatment with the same vitamins and using the same vitamin doses, dissolved in 1% aqueous solution of lead acetate. In all cases the time of drinking was 6 months. It was found that lead content in samples of tissues from testis, epididymis and in a whole blood in Pb- and Pb with antioxidants treated rats was significantly elevated. Chemiluminescence (CL) emitted by the Pb-treated tissues was significantly higher when compared to the light emission by tissues isolated from the animals of control group. The increase in the CL caused by lead occurs in the following increasing order within the studied tissues: cauda of epididymis <testis< caput of epididymis (19%, 39% and 51%, respectively). Dietary vit C supplementation to the Pb-treated rats for 6 months period decreased the CL from caput of epididymis, cauda of epididymis and testis (by 43%, 24%, 39%, respectively) more effectively in comparison to the control group (35%, 17%, 33%, respectively). Also stronger quenching effect on the light emission from the above mentioned tissues after Trolox supplementation was observed in the Pb-treated group (42%, 21%, 35%, respectively) than in the control group (23%, 13%, 13% respectively). The combination of both antioxidants treatments (vit C and Trolox) did not give a higher significant quenching effect compared to the treatment with the vitamins separately. No ultrastructural changes were found in the seminiferous epithelium of Pb-treated animals. However, we found abnormalities in ultrastructure of epididymal epithelial cells and epididymal spermatozoa in rats of Pb-treated groups. These findings provide ex vivo evidence that Pb causes oxidative cellular damage in reproductive system tissues of adult male rats, which may be closely associated with the ROS production.

Concentration of lead in mineral salt mixtures used as supplements in cattle food

We measured lead concentrations in samples of mineral salt mixtures used in cattle feed in the states of Paraná and São Paulo, Brazil. Lead content was determined spectrometrically by the atomic plasma induction method. Of the 30 samples analyzed, 9 had lead concentrations above 30 ppm (range 35.7 to 284.5 ppm) which is the maximum concentration recommended by the National Research Council (NRC 1980). These findings show the necessity for careful industrial monitoring because some mineral mixtures contain sufficient lead to cause toxicity.

In Situ Determination of Lead in Paint by Laser-Induced Breakdown Spectroscopy Using a Fiber-Optic Probe

On-site determination of leaded paint in houses is important for minimizing the costs of renovations. A simple fiber-optic probe suitable for remote elemental analysis using laser-induced breakdown spectroscopy has been developed for this purpose and is used to determine the lead concentration in samples of dry paint. Optical fibers transport the laser pulse to the sample and transfer the emission signal to the spectrometer. The use of separate excitation and collection fibers allows coupling of the probe to a conventional spectrometer using simple optics. The measurement takes less than 1 min to perform, requires no sample preparation, and can be made through overlayers of non-lead-containing paint. The limit of detection is 0.014% Pb in latex paint, on a dry weight basis, with relative sample standard deviations of 5−10%.

Lead Concentration in Breast Milk of Nursing Mothers Living in Riyadh

Lead poisoning has proven to be one of the most difficult environmental health problems. Part of this difficulty is based on the lack of distinctive manifestations at an early phase in the process. Breast milk feeding with high lead concentration is one of the first sources of lead exposure in neonates. This study reported that lead in breast milk samples from 81% of nursing mothers varied from a low concentration of 0.318 microg/dL to a high of 2.5 microg/dL with an average of 0.768 +/- 0.42 microg/dL. The high lead concentration of 2.5 microg/dL recorded in this study is similar to the average lead concentration reported by others. Lead concentration was found to be low in young mothers and higher in mothers age 36 years or more with an average of 0.515 +/- 0.14 and 1.344 +/- 0.65 microg/dL respectively. There were no significant differences between lead concentration in samples obtained from right or left breasts and similarly, there were no significant differences in lead concentrations in milk samples in relation to the length of period of lactation (P>/=0.1). Breast milk samples obtained from mothers residing near industrial areas or highways, using copper casserole coated with white (rich in lead) inner coat and eating food material preserved for long periods in metal containers showed higher lead concentration than from those living in remote areas with reduced exposure. The diagnosis of lead poisoning required a constant awareness of its prevalence.

Cloud deposition to a spruce forest edge

Deposition from clouds to a spruce (Picea rubens Sarg.) forest edge on Hunter Mt. in the Catskill Mts of New York State was measured during 1987 and 1988 to determine whether the windward edge of forest floor receives greater deposition of water and ions via cloud water than the interior of a forest. Throughfall was used as a measure of deposition and was collected during cloud-only and mixed cloud-and-rain events along five windward-to-leeward transects in a 30 x 30 m forested area. Ambient cloud water was also collected in a passive collector and chemically analyzed. Trees at the edge of the forest received on average three times, and up to 15 times, greater deposition of ions than those in the interior of the forest. Lead content in samples from Hunter Mt. forest floor at the windward edge, relative to the interior, was enhanced as well. Using a regression of distance vs deposition, the deposition “half-distance”, (i.e. the point at which the rate of cloud water deposition is 50% of the rate at the windward edge of the forest) was found to be 28 m. The cloud deposition data from this study are compared to other studies of Na particle deposition to low-elevation forest edges, which show similar deposition “half distances”, ranging from ∼ 2 to 36 m into the forest. Most models of cloud deposition currently in use assume landscape homogeneity. Montane forest landscapes, however, are often highly heterogeneous, consisting of many “edges”, and thus current models may seriously underestimate cloud deposition.

Determination of Levels of Lead Contamination in Food and Feed Crops

A rapid, precise procedure is described for the determination of lead in food and feed products with electrothermal atomic absorption spectrophotometry. Samples were mineralized in a microwave acid digestion bomb in the presence of nitric acid and vanadium pentoxide. Lead concentrations were determined directly from digested samples. The detection limit was 0.04 ng/mL. Accuracy and precision were checked against National Institute of Standards and Technology standard reference material. The analytical method was tested with 51 food and feed crops from Mediterranean zones in Spain and found to be suitable for these products. Lead concentrations in samples ranged from not detectable to 2.695 micrograms/g (fresh weight).

Lead in bone. IV. Distribution of lead in the human skeleton.

Flameless atomic absorption spectroscopy was used to measure lead concentrations in samples from 5 selected human skeletal sites (tibia, skull, rib, ilium, and vertebra) obtained from 134 hospital autopsies. Lead was distributed unequally among the different bones in distinct patterns that were age-, and to some extent, sex-dependent. To estimate lead concentration of the entire skeleton, all skeletal bones were divided into 5 groups based on their approximate compact/trabecular bone ratios, considering each of our 5 sampled sites to be the prototype for each such group. Regression analysis of the 10 possible bone site pair values at different ages yielded age-related constants. These constants were incorporated into an equation we developed that can be used both to estimate mean skeletal lead concentration (Pb) of the entire body skeleton and also to predict the lead concentration at any of the other 4 bone sites if any 1 of the 5 is measured. Applications of these data to in vivo bone lead measurements are detailed with respect to selection of the site to be measured, estimation of total skeletal lead burden, anticipated variations or error, and dependence of these factors on age and sex of the sampled population.