Differences In Lead Concentrations Research Articles

Variation in heavy metals concentrations among seaweed species from Mkwiro seaweed farm, Kwale County, Kenya

This study, conducted at the Mkwiro seaweed farm in Kwale County, Kenya, aimed to assess the concentrations of heavy metals (Cd and Pb) and essential elements (Na, Fe, Ca, and K) in selected edible seaweed species. The study used a cross-sectional, descriptive research design and probability sampling method to collect data. Seaweed samples of three selected species, Cottonii (Kappaphycus alvarezii), Sea lettuce (Ulva lactuca), and Bubble-green seaweed (Boergesenia forbesii) were collected in quadrants and subjected to chemical analysis. Statistical analyses were conducted using R Studio version 4.3.2, with a significance level set at α=0.05. The Kruskal-Wallis test revealed significant differences in lead concentrations among seaweed types (χ² (2) = 7.01, p = 0.03). Cadmium concentrations did not show significant differences (χ² (2) = 3.88, p = 0.14). For calcium concentrations, ANOVA indicated no significant effect of seaweed type (F (2,33) = 0.6381, p = 0.5347). Iron concentrations differed significantly among seaweed types (χ² (2) = 23.35, p = 0.00000849), with B. forbesii having the highest median concentration. Potassium and sodium concentrations did not significantly vary among seaweed types (p > 0.05). The study uncovers elevated cadmium levels in seaweed, indicating potential contamination risks. However, concentrations of essential elements were lower. To address these findings, it is recommended to initiate regular monitoring and pollution control measures in seaweed farms. Additionally, diversifying cultivation with low-metal species can enhance product safety and quality.

Spatial, temporal and environmental differences in concentrations of lead in the blood of Mute swans from summer and winter sites in Poland

Lead (Pb) is a highly toxic pollutant and represents a serious threat to wildlife, affecting various systems in animal bodies. Especially prone to Pb poisoning are waterbirds, which may inadvertently ingest spent gunshot, fishing sinkers and contaminated sediments. This research thus focused on evaluating Pb concentrations in the blood of 170 Mute swans (Cygnus olor; a widespread species of waterbirds) at their summer (urban locations in Małopolskie and rural locations in Świętokrzyskie regions) and winter (the urban section of Wisła River in Krakow) sites in Poland (Europe). The study concentrated on comparing blood Pb concentrations according to sites and locations, verifying the influence of sex and age factors, examining the impact on hematocrit (Ht), glutathione (GSH) levels and body condition. Mean blood Pb concentrations (measured with ICP-OES) differed significantly between summer and winter sites (Regression by Maximum Likelihood Estimation (RML), p < 0.001) reaching higher values at winter sites. Concentrations did not differ from year to year (RML, p = 0.028). At summer sites, concentrations differed from location to location: swans from urban locations in Małopolskie had higher blood Pb concentrations (0.055 μg/g) than from rural Świętokrzyskie (0.008 μg/g; RML, p < 0.001). In summer and winter birds, neither sex nor age groups differed significantly the concentrations (RML, p > 0.231). Pb concentrations correlated weakly with Ht and GSH levels (Spearman test) and had no influence on body condition (proxied by scaled mass index; GLM, p = 0.246). We concluded that differences between summer and winter sites were dictated mainly by the type of habitat (rural vs. urban) that birds occupied in different seasons.

Relationship between heavy metal exposure and type 2 diabetes: a large-scale retrospective cohort study using occupational health examinations

ObjectivesTo investigate the associations between heavy metal exposure and serum ferritin levels, physical measurements and type 2 diabetes mellitus (DM).DesignA retrospective cohort study.SettingChangwon, the location of this study, is a...

Assessing the Regulatory Requirements of Lead-Based Perovskite Photovoltaics

Nicole Moody, Samuel Sesena, Dane W. deQuilettes, Benjia Dak Dou, Richard Swartwout, Anna Johnson, Udochukwu Eze, Roberto Brenes, Matthew Johnston, Vladimir Bulovic, and Moungi G. Bawendi are members of Tata-MIT GridEdge Solar, an interdisciplinary research program at the Massachusetts Institute of Technology working toward scalable design and manufacturing of lightweight, flexible solar cells. Joseph T. Buchman and Christy L. Haynes are part of the Center for Sustainable Nanotechnology, a multi-institutional partnership aimed at understanding the fundamental chemical and physical processes that govern the transformations and interactions of nanoparticles in the environment.

Comparison of lead contamination among related scavenging birds sharing food sources: a call for caution when using surrogate species

Lead contamination is a global problem affecting a large number of bird species around the world. Among the different avian guilds, vultures and facultative scavengers are particularly threatened by this toxic metal. However, little information is available about differences in exposure to this metal for sympatric vulture species that share food resources. We compared blood lead concentrations of two closely related sympatric obligate scavenger species, the abundant Black Vulture Coragyps atratus and the threatened Andean Condor Vultur gryphus in north‐western Patagonia, Argentina. We sampled 28 Andean Condors and 29 Black Vultures trapped foraging in the same area in the steppe. We also sampled 16 Black Vultures foraging in a rubbish dump to determine whether there were differences in lead contamination among foraging sites. Andean Condors had significantly higher mean blood lead concentrations than Black Vultures. There was no difference in lead concentrations between Black Vultures trapped in the steppe and in the rubbish dump. The prevalence and probability of lead concentrations above the threshold level (20 µg/dL) was higher for Andean Condors than for Black Vultures, potentially producing different effects on their health. This disparity in lead contamination may be due to differences in their foraging habits or in their susceptibility to this toxic metal. Overall, our results suggest caution in using an abundant surrogate species to infer lead contamination in a closely related but harder to sample species.

Environmental Impact Assessment of Tehran- Karaj Highway by Using Plants Indicators

Lead pollution is one of the negative impacts of roads on environment, which can be assessed using environmental impact assessment. As a study case, Tehran- Karaj highway was selected for studying environmental lead pollution in pine tree needles (plants indicators). Samples were collected from seven stations and five distances (0, 10, 20, 50, 100 meter). The results showed that transport has a direct effect on lead pollution in trees. The differences in lead concentrations were significant for both stations and distances. The average lead concentration was 11.34 mg/Kg in the station close to Tehran, and 3.8 mg/Kg in the closest station to Karaj. This is because heavier transfer and higher density of cars in Tehran compared to Karaj. The average Pb concentrations in the stations besides the highway was 8.77 mg/Kg and decreased to 6.57 mg/kg in stations located in 100 meter away from the highway. While the average Pb concentration in station E was 1.53 mg/Kg, it was decreased constantly in all distances, due to tree coverage. A conclusion, the analytical method of roads environmental impact assessment can be used effectively for monitoring Pb pollution. The pollution can be decreased by using pine trees and emphasis on using windbreakers.

Determination of lead concentration in water and in different organs of Carrasobarbus luteus and Cyprinus carpio Tigris River

The present study was carried out during the period from November 2015 to April 2016 to determine the concentration of lead in Tigris River. A total of 75 fish of Hamri Carrasobarbus luteus and 82 specimen of common carp Cyprinus carpio were sampled at three different stations. Atomic absorption spectrometry is a technique for measuring quantities of Lead present in water and fish. The results showed that the mean concentration of lead in water more than in fish organs. Statistical analysis showed no significant differences in lead concentration between all stations. In C. luteus and C. carpio showed no significant differences in gills, muscles, liver and kidney between different length groups for each station. Length group 21- 30 cm at station 2 showed increasing differences compared with the same length group at station 1, Also C. carpio of Length group 31-40 cm at station 2 showed significantly increasing (P≤0.05) compared with the same length group at station 1. The highest concentration of lead was recorded in studied organs of C. luteus at station1as the following sequence: Gills &gt; kidney &gt; liver &gt; muscles, while station 2: kidney &gt; gills &gt; liver &gt; muscles, station 3 characterized as following sequence: Kidney &gt; liver &gt; gills &gt; muscles. The highest concentration of lead was recorded in studied organs of C.carpio at station1as the following sequence: Gills &gt; liver &gt; muscles &gt; kidney, while station 2: Gills &gt; kidney &gt; liver &gt; muscles, station 3 characterized looks like a sequence of station 1 as following: Gills &gt; liver &gt; muscles &gt; kidney. In conclusion, the result of the present study approved the presence of lead in the water of Tigris River and fish living inside it. In addition, the mean concentration of lead in water was more than in fish organs. The results also reported that lead concentration was higher than the allowable WHO concentration.

The Effect of Cocoa Beans Heavy and Trace Elements on Safety and Stability of Confectionery Products

Abstract The aim of the study was to evaluate cocoa beans quality produced in Cameroon, Ecuador, Nigeria and Ghana from safety position determining heavy and trace metals concentration and evaluating the oxidative stability of confectionery products prototypes (trials) with analysing cocoa beans. For evaluation of oxidative stability of confectionery products, the main ingredients - butter and cocoa beans kernels were tested making trials as milk chocolate prototype. The composition of confectionery ingredients affects quality of products; therefore it is very important to evaluate quality of raw materials in confectionery industry, as they are purchased practically in all regions of the world. Mercury, arsenic, lead, cadmium concentration was determined in whole cocoa beans as their presence in foods have toxic effect on human beings and their concentration are strictly limited as maximum residue limits for processing. Cocoa shells can be used as additive to confectionery products recipes therefore the object of the study was cocoa beans and cocoa shells. Analyzing cocoa beans quality indices there was established that lead, cadmium, aluminium and zinc concentrations vary in cocoa beans significantly. Differences in lead concentration in cocoa beans from Ghana, Cameroon and Ecuador were significant (p &lt; 0.05) compared with concentration of lead in cocoa beans from Nigeria (p &gt; 0.05). Cadmium concentration in cocoa beans from Cameroon was significantly different comparing with cocoa beans from Nigeria, Ecuador and Ghana (p &gt; 0.05). Differences in aluminium concentration in cocoa beans kernels were significant (p &lt; 0.05) in all analyzed samples. Concentration of zinc was higher in shells of cocoa beans, especially in shells of cocoa beans from Ecuador (p &lt; 0.05). The presence of cocoa products in milk chocolate prototypes inhibited the speed of lipid peroxidation. The different trace and heavy metals concentrations in cocoa beans should be taken into account choosing ingredients and components for confectionary products production particularly those with high content of cocoa (chocolates, sweets, cocoa fillings, cocoa creams and others) with the aim to prevent oxidation process during shelf-life of products.

The bioaccumulation of lead in the organs of roe deer (Capreolus capreolus L.), red deer (Cervus elaphus L.), and wild boar (Sus scrofa L.) from Poland.

The aim of this study was to evaluate the level of lead (Pb) in the livers and kidneys of free-living animals from Poland, with regard to the differences in tissue Pb content between the species. The research material consisted of liver and kidney samples collected from roe deer (Capreolus capreolus), red deer (Cervus elaphus), and wild boar (Sus scrofa) that had been hunted in 16 voivodeships of Poland. The concentration of lead had been measured using inductively coupled plasma optical emission spectrometry (ICP-OES) method. The results show that differences in lead concentration in the organs depended on the geographic location. In roe deer and red deer, the highest mean lead concentrations in the livers and kidneys, observed in the central region of Poland, were twice as high as the lowest concentration of Pb in these animals from the northeastern region of the country. In wild boar, the highest mean concentration of Pb was noted in the livers of animals from the central region of Poland and in the kidneys of animals from the northwestern region, while the lowest lead concentrations in both organs were typical for wild boar from the southeast part of the country. Our results show that areas located in the center and in the north of Poland carry most of the burden of lead bioaccumulation.

Using Community-Based Participatory Research to Explore Backyard Gardening Practices and Soil Lead Concentrations in Urban Neighborhoods.

Lead exposure is a serious health threat for children. Soil is an important exposure pathway, primarily through ingestion and inhalation. Urban agriculture is increasing. Potential environmental health risks associated with residential gardening may not be well known to community residents. A community-based participatory research (CBPR) approach was implemented to explore the relationship between urban residential vegetable gardening and lead exposure in children. The primary objectives were to characterize local backyard vegetable gardening practices, measure residential and commercial soil lead concentrations and spatial distributions, and identify priorities for individual and collective action. Participants were recruited in two stages. In phase 1, adult gardeners participated in structured interviews. In phase 2, a multistage representative sampling approach was implemented to recruit adult gardeners for interviews and soil testing. Twenty adults participated in gardening practice interviews. Adults perceive many benefits from backyard gardening and initially expressed few concerns about lead exposure risk. Results indicate that children are actively involved in backyard gardening. Total soil lead concentrations from 17 residential properties ranged from 7 to 3,234 mg kg-1(median, 187; mean, 432). Commercial soils had lead concentrations that ranged from 6 to 13 mg kg(-1) (median, 6.5; mean, 7.6). Nonparametric Mann-Whitney comparisons indicated a significant difference in lead concentration between commercial soil and residential soil (p<0.0001). Advocacy for resources needed to eliminate dangerous levels of lead from the environment, especially in communities where divestment has occurred, is enhanced through CBPR. Increasing access to soil testing is an important action step.

Assessment of Toxic Metals in Dairy Milk and Animal Feed in Peshawar, Pakistan

Aims: To assess the concentration of toxic heavy metals [Cadmium, Copper, Lead and Nickle] in dairy milk and animal feed of urban and rural areas and correlate them. Study Design: It was a cross-sectional comparative study. Place and Duration of Study: The study was conducted on the dairy milk and animal feed in milk farms of Peshawar. The samples were collected during June – July of 2010. Methodology: The study area was divided into two zones: urban area which was located in the centre of the city and rural area comprising of peri urban villages. Fifty milk samples were collected, 30 from urban and 20 from rural areas. Feed samples were also collected. Milk and feed samples were prepared by wet digestion method using HNO3 and H2O2 as described by Association of Official Analytical Chemists (AOAC) of North America, 1990. This was followed by analysis on Atomic Absorption Spectrometer. Results: The results showed that the mean concentration of toxic heavy metals under study namely Cadmium, Copper, Lead and Nickle were greater in dairy milk than the maximum residue limits (MRLs) of these elements as given by Joint Expert Committee on Food and Agriculture and World Health Organization. In comparison of urban and rural areas it was found that higher concentration of Cadmium, Copper, and Nickle was found Original Research Article British Biotechnology Journal, 4(8): 883-893, 2014 884 in dairy milk samples from urban areas than rural areas but there was no significant difference in Lead concentration of the two areas. Their concentration in urban and rural samples were respectively Cadmium 0.69 and 0.037 with P-value <0.001, Copper 1.40 and 0.09 with P-value 0.001, Nickel 0.806 and 0.024 with P-value <0.001, Lead 2.243 and 2.082 with P -value 0.026. However in this study all these elements were within the permissible limits in animal feed except for copper in cotton khal which was 83.3mg kg against the MRL of 10 mg kg given by National Research Council, NRC, 2005. Also there was no significant difference in the concentration of these elements in feed of urban and rural areas. Correlation study between the concentration of these elements in milk and feed showed positive pearson’s correlation coefficient between the two particularly for copper (0.451) in sugarcane khal and (0.341) in wheat grain, Nickle (0.342) in maize, and (0.30) in wheat bran and cotton khal. Conclusion: The concentrations of toxic metals were higher than the maximum residue limits in milk but were within their normal limits in animal feed suggesting that milk is being contaminated by various other sources but not farm feed. Comparison between urban and rural areas showed higher concentration in urban milk samples as compared to rural except for lead probably because urban farms are located in polluted areas in the centre of the city. However no significant difference was found in animal feed of urban and rural areas because it is supplied from common source.

Assessment of lead exposure in Spanish imperial eagle (Aquila adalberti) from spent ammunition in central Spain

The Spanish imperial eagle (Aquila adalberti) is found only in the Iberian Peninsula and is considered one of the most threatened birds of prey in Europe. Here we analyze lead concentrations in bones (n=84), livers (n=15), primary feathers (n=69), secondary feathers (n=71) and blood feathers (n=14) of 85 individuals collected between 1997 and 2008 in central Spain. Three birds (3.6%) had bone lead concentration>20μg/g and all livers were within background lead concentration. Bone lead concentrations increased with the age of the birds and were correlated with lead concentration in rachis of secondary feathers. Spatial aggregation of elevated bone lead concentration was found in some areas of Montes de Toledo. Lead concentrations in feathers were positively associated with the density of large game animals in the area where birds were found dead or injured. Discontinuous lead exposure in eagles was evidenced by differences in lead concentration in longitudinal portions of the rachis of feathers.

Excess Lead in the Neural Retina in Age-Related Macular Degeneration

To measure lead and cadmium in retinal tissues of human donor eyes with and without age-related macular degeneration (AMD). Laboratory investigation. Lead and cadmium concentrations in retinal tissues (neural retina and retinal pigment epithelium [RPE]-choroid complex) in 25 subjects with AMD (50 donor eyes) and 36 normal subjects (72 donor eyes) were determined by using inductively coupled plasma-mass spectrometry. Severity of AMD was graded by using color fundus photographs and the Minnesota Grading System. Differences in metal concentrations were compared by using Wilcoxon rank-sum tests. The neural retinas of subjects with AMD had increased lead concentrations (median, 12.0 ng/g; 25% to 75% interquartile range, 8 to 18 ng/g; n = 25) compared with normal subjects (median, 8.0 ng/g; 25% to 75% interquartile range, 0 to 11 ng/g; P = .04; n = 36). There was no difference in lead concentration in the RPE-choroid complex between subjects with AMD (median, 198 ng/g; 25% to 75% interquartile range, 87 to 381 ng/g) and normal subjects (median, 172 ng/g; 25% to 75% interquartile range, 100 to 288 ng/g; P = .25). Cadmium concentration in the neural retina (median, 0.9 microg/g; 25% to 75% interquartile range, 0.7 to 1.8 microg/g) and RPE-choroid complex (median, 2.2 microg/g; 25% to 75% interquartile range, 1.8 to 3.7 microg/g) in subjects with AMD was not different from concentrations in the neural retina (median, 0.9 microg/g; 25% to 75% interquartile range, 0.7 to 1.4 microg/g; P = .32) and RPE-choroid complex (median, 1.5 microg/g; 25% to 75% interquartile range, 0.9 to 2.5 microg/g; P = .12) of normal subjects. AMD is associated with excess lead in the neural retina, and this relationship suggests that metal homeostasis in AMD eyes is different from normal.

Ingestion of lead from ammunition and lead concentrations in white-tailed sea eagles ( Haliaeetus albicilla) in Sweden

In this study we show for the first time that lead poisoning from ammunition is a significant mortality factor for white-tailed sea eagle (WSE) ( Haliaeetus albicilla) in Sweden. We analyzed 118 WSEs collected between 1981 and 2004 from which both liver and kidney samples could be taken. A total of 22% of all eagles examined had elevated (> 6 µg/g d.w.) lead concentrations, indicating exposure to leaded ammunition, and 14% of the individuals had either liver or kidney lead concentrations diagnostic of lethal lead poisoning (> 20 µg/g d.w.). Lead concentrations in liver and kidney were significantly correlated. In individuals with lead levels < 6 µg/g, concentrations were significantly higher in kidney than in liver; in individuals with lead levels > 20 µg/g, concentrations were significantly higher in liver. The lead isotope ratios indicate that the source of lead in individuals with lethal concentrations is different from that of individuals exhibiting background concentrations of lead (< 6 µg/g d.w.) There were no significant sex or age differences in lead concentrations. A study from the Baltic reported in principle no biomagnification of lead, but background lead concentrations in WSE liver in this study were still four to > 10 times higher than concentrations reported for Baltic fish from the same time period. In contrast to other biota there was no decrease in lead concentrations in WSE over the study period. The proportion of lead poisoned WSE remained unchanged over the study period, including two years after a partial ban of lead shot was enforced in 2002 for shallow wetlands. The use of lead in ammunition poses a threat to all raptors potentially feeding on shot game or offal. The removal of offal from shot game and alternatives to leaded ammunition needs to be implemented in order to prevent mortality from lead in raptors and scavengers.

Entry of Heavy Metals into Food Chains: a 20-year Comparison Study in Northern Moravia (Czech Republic)

The aim of the study presented here was to assess cadmium, lead and mercury contamination of wild-living animals and cattle in Northern Moravia (Czech Republic). Samples were collected in 2005–2007 at the same locations as in 1986–1989, in the same season of the year, and they were analyzed using the same methods (AAS ). In 2005–2007, a significant decrease (P &lt; 0.01) in cadmium concentrations in plant fodders was found, while changes in lead and mercury concentrations were less marked, and they depended on the type of commodity. In the 2005–2007 period, a marked decrease (P &lt; 0.01) in cadmium concentrations in the muscle and kidneys of the cattle, fallow deer, roe deer and pheasants (muscle 0.002–0.009 mg kg-1, kidneys 0.11–0.69 mg kg-1) was found. In the same period, mercury concentrations in the muscle, liver and kidneys were significantly lower (P &lt; 0.01) in cattle, roe deer and hare tissues (muscle: 0.6–3.5 μg kg-1, liver 3.3–41.0 μg kg-1, kidney 16.3–43.2 μg kg-1). Lower lead concentrations in the 2005–2007 period were only found in cows (0.04 mg kg-1, 0.1 mg kg-1 and 0.6 mg kg-1 in muscle, liver and kidney samples, respectively). No significant differences in lead concentrations were found in the tissues of other animals. The study demonstrated a reduction in the amounts of heavy metals entering food chains in the study area in recent years.

Regional and long-term patterns of lead concentrations in riverine, marine and terrestrial systems and humans in northwest Europe

Lead contamination of abiotic and biotic systems has beenstudied closely since the early 1970s, when lead was firstperceived as an environmental problem. Lead emission reductionpolicies were implemented throughout Europe during that time.Nonetheless, analyses of lead loads in aquatic systems, such asthe River Elbe, showed no decline over time in either suspendedmatter or surface sediments. Regional differences in leadconcentrations of fluvial, i.e. riverine systems were found,due to tidal influence, runoff and local emissions. Leadcontamination of sediments from the North Sea was highest inestuaries. Concentrations in sediment cores were quite stabledown to the depth of background values, due to bioturbation,flow, waves and meandering channels. Terrestrial soils inEurope were highly polluted in industrial and ore mining areasand large cities. No decline in lead concentrations was evident in foraminifera,bladder wrack or fish. It was found that contamination insediments, mammals and fish livers was higher in coastal zonesthan in the open sea. In contrast to aquatic organisms,positive impacts of lead reduction regulations were detected interrestrial plants, which adsorbed or took up lead mainlythrough atmospheric lead deposition. European leadconcentrations in plants decreased coincidently with leademissions. That trend could also be identified in the bloodlead levels of the human population in Europe: since 1979 theyhave declined in every group of the population. Mainlyinfluenced by age, sex and the living environment, overall, thelead loads of humans had never been high enough to cause healtheffects.

Elevated dentine-lead levels in deciduous teeth collected from remote first nation communities located in the western James Bay region of northern Ontario, Canada.

Teeth were collected from First Nation schoolchildren inhabiting the remote western James Bay region of northern Ontario, Canada. Lead levels in dentine chips were determined by graphite furnace atomic absorption spectrometry, for naturally exfoliated deciduous teeth. Within exfoliated teeth (one tooth supplied per person), no significant differences in lead concentrations between tooth type were found (P = 0.36). The mean lead concentration of exfoliated teeth of 9.2 microg g(-1) dry weight (N = 61) from this remote region was comparable to levels reported by others for children inhabiting urban centers or residing near smelters. Further, 24.6% (N = 15) had elevated dentine-lead levels ( > 10 microg g(-1)). Lead levels in soil, water, and air have been reported as being low and unimportant sources of exposure for people of the western James Bay area. Evidence is reviewed suggesting that lead contaminated game meat was one source of environmental lead exposure. Consumption data indicate that wildlife is still an important food source for First Nation people of the western James Bay region; 98% (46/47) of the children surveyed consumed some type of wild meat.

Determination of urinary lead in school children in Manzini, Swaziland, Southern Africa

Two hundred and fifty-seven urine samples collected from school children living in the Manzini region, Swaziland, were analysed for lead (Pb), using a graphite furnace atomic absorption spectrometer. The mean urine lead concentration for the urban schools ranged from 0.038–0.040 μg⋅ml−1, while that for the rural schools ranged from 0.017–0.022 μg⋅ml−1. The observed range shown by the urban schools was above the normal (for healthy humans) urine lead concentration of 0.035 μg⋅ml−1. However, the mean urine lead concentration for the rural schools was found to be lower than this value. The mean urine lead concentration for the urban schools was significantly higher than that of the rural schools. The differences in the mean urine lead concentrations for boys and girls from both urban and rural schools were found not to be significant, despite the higher values shown by the girls. The difference in lead concentrations between urban and rural schools in Manzini was thought to be due to the traffic density within the urban area.

Lead isotope measurements on aerosol samples with ICP-MS.

Size fractionated aerosols were collected with low pressure Berner impactors on a radio/TV tower 110 m above ground on a hill 10 km east of Bern at a total elevation of 1060 m asl. Two different wind sectors were chosen with the goal of assessing any differences in lead concentration and the 3 radiogenic lead isotopes (206,207,208) for east and west wind, respectively. A leaching technique was used to extract the lead quantitatively from the surface of the impaction foils. This method has been proven to be better suited for airborne particles than complete microwave digestion because it is less time consuming and contamination risk is smaller. Blank considerations played a major role in choosing all the chemicals, tubes, beakers and selecting the analytical method. Lead concentrations were determined with GF-AAS and lead isotopes with two different ICP-MS systems, one being a multicollector system. Precision of the simultaneous multicollector system was found to be at least a factor of 3 better than that of the sequentially operating ICP-MS. The small variations in isotope ratios from the two wind sectors can be distinctly seen with this enhanced precision. The observed relative difference in isotope ratios between east- and westwind was approximately 0.6% for 207Pb/206Pb and approximately 0.5% for 208Pb/206Pb.

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.