Median Pb Concentrations Research Articles

Organic contaminants and heavy metals in indoor dust from e-waste recycling, rural, and urban areas in South China: Spatial characteristics and implications for human exposure

The concentrations of several organic contaminants (OCs) and heavy metals were measured in indoor dust from e-waste recycling, rural, and urban areas in South China to illustrate the spatial characteristics of these pollutants and to further evaluate human exposure risks. The median concentrations of polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), decabromodiphenyl ethane (DBDPE), and dechlorane plus (DPs) were 38.6–3560, 2360–30,100, 665–2720, and 19.5–1860ng/g, while the median concentrations of Cd, Pb, Cu, Cr, and Zn were 2.46–40.4, 206–1380, 217- 1200, 25.3–134, and 176–212μg/g in indoor dust. The levels of all pollutants, except Zn, in dust from the e-waste recycling area were significantly higher than those from the other areas. Cd, Pb, and most OCs exhibited similar pollution patterns in the three areas, indicating that e-waste recycling activities are the major pollution source. In contrast, Cu, Cr, Zn, and penta-BDE are likely derived from household products in the rural and urban areas. The highest estimated daily intakes (EDIs) of PCBs, PBDEs, DBDPE, and DPs were 0.15–163, 3.97–1470, 1.26–169, and 0.11–134ng/kg bw/day for toddlers and adults. The highest EDIs of BDE 209 and Pb in toddlers in the e-waste recycling area were 16% and 18 times higher than the reference doses, indicating the high exposure risk of these pollutants in the e-waste recycling area.

Maternal and fetal exposure to cadmium, lead, manganese and mercury: The MIREC study

Given the susceptibility of the fetus to toxicants, it is important to estimate their exposure. Approximately 2000 pregnant women were recruited in 2008–2011 from 10 cities across Canada. Cd, Pb, Mn and total Hg were measured in maternal blood from the 1st and 3rd trimesters, umbilical cord blood, and infant meconium. Nutrient intakes of vitamin D, iron, and calcium (Ca) were assessed using a food frequency questionnaire and a dietary supplement questionnaire.Median concentrations in 1st trimester maternal blood (n = 1938) were 0.20, 8.79 and 0.70 μg/L for Cd, Mn and Hg, respectively, and 0.60 μg/dL for Pb. While the median difference between the paired 1st and 3rd trimester concentrations of Cd was 0, there was a significant decrease in Pb (0.04 μg/dL) and Hg (0.12 μg/L) and an increase in Mn (3.30 μg/L) concentrations over the course of the pregnancy. While Cd was rarely detected in cord blood (19%) or meconium (3%), median Pb (0.77 μg/dL), Mn (31.87 μg/L) and Hg (0.80 μg/L) concentrations in cord blood were significantly higher than in maternal blood. Significant negative associations were observed between estimated Ca intake and maternal Cd, Pb, Mn and Hg, as well as cord blood Pb. Vitamin D intake was associated with lower maternal Cd, Pb, and Mn as well as Pb in cord blood.Even at current metal exposure levels, increasing dietary Ca and vitamin D intake during pregnancy may be associated with lower maternal blood Pb and Cd concentrations and lower Pb in cord blood.

Trace element geochemical evolution and groundwater origin in North Rukuru–Songwe alluvial aquifer of northern Malawi

This study used multivariate analysis and geochemical modeling to appreciate the trace element evolution in North Rukuru–Songwe alluvial aquifer of northern Malawi. From the isotopic studies, the δ2H/δ18O ratios revealed that groundwater is of meteoric origin through vertical recharge and mixing processes. The isotopic depletion along the west–east transect is due to mixing and fractionation processes. Generally, the d-excess value approximated the y-intercept of global meteoric water line of 10, which ruled out the influence of secondary evaporative processes on isotopic variation. Hierarchical cluster analysis identified four distinct clusters (C1, C2, C3 and C4) in the study area. Among these four clusters, it was observed that C1 had relatively high median concentrations of Fe (716.7 µg/L), Cr (0.85 µg/L), Pb (7.90 µg/L) and Sb (3.80 µg/L), while C2 was characterized by high levels of Cu (3.20 µg/L). Cluster 3 was comparably defined by high median levels of F (1.00 mg/L) and Mn (338 µg/L), while C4 revealed high median concentrations of As (8.70 µg/L), Ba (635 µg/L), Li (22.2 µg/L), Ni (2.80 µg/L), Se (6.20 µg/L) and Sr (677 µg/L). Clusters C1 and C4 described a flow path along the North Rukuru River, which is characterized by higher levels of evaporites as shown by higher concentrations of Na, K, Cl and SO4. It was also observed that this path was defined by high levels of HCO3 and total hardness. The principal component analysis suggests that carbonate dissolution and silicate weathering are the main mineralization control mechanisms. Furthermore, it is revealed that samples in the west had higher factor scores for As, Ba, Li, Ni, Se and Sr (with higher TDS), while the eastern is characteristic of higher heavy metals (Fe and Pb). Geochemical modeling using PHREEQC showed that surface complexation reactions significantly impact trace elements of higher redox state. In addition, inverse modeling confirms the significance of carbonate dissolution, silicate weathering and cation exchange processes along the North Rukuru River flow path.

The legacy of lead (Pb) in fluvial bed sediments of an urban drainage basin, Oahu, Hawaii.

The study of fluvial bed sediments is essential for deciphering the impact of anthropogenic activities on water quality and drainage basin integrity. In this study, a systematic sampling design was employed to characterize the spatial variation of lead (Pb) concentrations in bed sediment of urban streams in the Palolo drainage basin, southeastern Oahu, Hawaii. Potentially bioavailable Pb was assessed with a dilute 0.5 N HCl extraction of the <63 μm grain-size fraction from the upper bed sediment layer of 169 samples from Palolo, Pukele, and Waiomao streams. Contamination of bed sediments was associated with the direct transport of legacy Pb from the leaded gasoline era to stream channels via a dense network of storm drains linked to road surfaces throughout the basin. The Palolo Stream had the highest median Pb concentration (134 mg/kg), and the greatest road and storm drain densities, the greatest population, and the most vehicle numbers. Lower median Pb concentrations were associated with the less impacted Pukele Stream (24 mg/kg), and Waiomao Stream (7 mg/kg). The median Pb enrichment ratio values followed the sequence of Palolo (68) > Pukele (19) > Waiomao (8). Comparisons to sediment quality guidelines and potential toxicity estimates using a logistic regression model (LRM) indicated a significant potential risk of Palolo Stream bed sediments to bottom-dwelling organisms.

Lead in Chinese villager house dust: Geographical variation and influencing factors

House dust has been recognized as an important contributor to Pb exposure of children. Here we conducted a comprehensive study to investigate geographical variation of Pb in Chinese villager house dust. The influences of outdoor soil Pb concentrations, dates of construction, house decoration materials, heating types, and site specific pollution on Pb concentrations in house dust were evaluated. The concentrations of Pb in 477 house dust samples collected from twenty eight areas throughout China varied from 12 to 2510 mg/kg, with a median concentration of 42 mg/kg. The median Pb concentrations in different geographical areas ranged from 16 (Zhangjiakou, Hebei) to 195 mg/kg (Loudi, Hunan). No correlations were found between the house dust Pb concentrations and the age of houses, as well as house decoration materials. Whereas outdoor soil, coal combustion, and site specific pollution may be potential Pb sources. Principal component analysis (PCA) confirmed that elemental compositions of the house dust were controlled by both anthropogenic and geogenic sources. Using scanning electron microscopy (SEM), the Pb bearing particles in the house dust were also studied.

Metal and metalloid accumulation in cultivated urban soils: A medium-term study of trends in Toronto, Canada

This study aims to examine the elemental enrichment patterns in low to medium traffic areas over a three year period in Toronto, Canada. Soils were sampled at three locations with different volumes of traffic between 2010 and 2013. A range of elements, including V, Cr, Mn, Cu, Cd, As, Sb and Pb, were measured in acid digested samples using ICP-MS. While the concentrations of Cd, Sb and Pb were found to be relatively low, a significant, albeit small increase in their levels over time was determined for all sites. For the low traffic areas, median Cd, Sb and Pb concentrations increased from 0.18mg Cd/kg, 0.14mg Sb/kg and 12mg Pb/kg in 2010 to 0.38mg Cd/kg, 0.21mg Sb/kg and 15mg Pb/kg in 2012, respectively. For the medium traffic site, the respective levels of Cd and Sb rose from 0.19mg Cd/kg and 0.14mg Sb/kg in 2010 to 0.49mg Cd/kg and 0.28mg Sb/kg in 2012. Median Pb concentrations at the medium traffic site were comparable to those at the low traffic sites (13mg/kg in 2010 and 15mg/kg in 2012). Principal Component Analysis (PCA) revealed the existence of two components (rotated), which explained 77% of the variance for all sites: 1. PC1 with large loadings of V, Cr, Co and Cu that likely originate from the commercial soil originally used for monitoring purposes, and 2. PC2 with high correlations between Cd, Sb and Pb, attributed to traffic sources of emissions. The resuspension and transport of more mobile fractions of contaminated dust and soil particles is hypothesized to be contributing to an elemental enrichment of soils located in low traffic areas.

Prenatal exposure to lead in relation to risk of preterm low birth weight: A matched case-control study in China.

We investigated the association between prenatal exposure to lead (Pb) and the risk of preterm low birth weight (PLBW). Pb concentrations in maternal urine collected at birth from 408 subjects (102 cases and 306 matched controls) were analyzed and adjusted by creatinine. The median Pb concentration in the PLBW cases (10.60μgPb/g creatinine) was higher than that of the controls (7.28μgPb/g creatinine). An adjusted odds ratio (OR) of 2.96 (95% CI=1.49-5.87) for PLBW was observed when the highest tertile was compared to the lowest tertile of Pb levels. The association was more pronounced among female infants (adjusted OR=3.67 for the highest tertile; 95% CI=1.35-9.93) than male infants (adjusted OR=1.91 for the highest tertile; 95% CI=0.74-4.95). Our study suggests that prenatal exposure to levels of Pb encountered today in China is associated with an elevated risk of PLBW.

Microarray-based analysis of gene expression in lycopersicon esculentum seedling roots in response to cadmium, chromium, mercury, and lead.

The effects of heavy metals in agricultural soils have received special attention due to their potential for accumulation in crops, which can affect species at all trophic levels. Therefore, there is a critical need for reliable bioassays for assessing risk levels due to heavy metals in agricultural soil. In the present study, we used microarrays to investigate changes in gene expression of Lycopersicon esculentum in response to Cd-, Cr-, Hg-, or Pb-spiked soil. Exposure to (1)/10 median lethal concentrations (LC50) of Cd, Cr, Hg, or Pb for 7 days resulted in expression changes in 29 Cd-specific, 58 Cr-specific, 192 Hg-specific and 864 Pb-specific genes as determined by microarray analysis, whereas conventional morphological and physiological bioassays did not reveal any toxicant stresses. Hierarchical clustering analysis showed that the characteristic gene expression profiles induced by Cd, Cr, Hg, and Pb were distinct from not only the control but also one another. Furthermore, a total of three genes related to "ion transport" for Cd, 14 genes related to "external encapsulating structure organization", "reproductive developmental process", "lipid metabolic process" and "response to stimulus" for Cr, 11 genes related to "cellular metabolic process" and "cellular response to stimulus" for Hg, 78 genes related to 20 biological processes (e.g., DNA metabolic process, monosaccharide catabolic process, cell division) for Pb were identified and selected as their potential biomarkers. These findings demonstrated that microarray-based analysis of Lycopersicon esculentum was a sensitive tool for the early detection of potential toxicity of heavy metals in agricultural soil, as well as an effective tool for identifying the heavy metal-specific genes, which should be useful for assessing risk levels due to heavy metals in agricultural soil.

Metal contamination of sediment by paint peeling from abandoned boats, with particular reference to lead

Fragments of flaking paint have been sampled from eighteen boats (including sailing barges, houseboats, a trawler and a ferry) abandoned on the intertidal mudflats of two estuaries in eastern England and analysed for Cu, Pb and Zn by X-ray fluorescence (XRF) spectrometry. Median concentrations of Pb on each boat ranged from about 350 to 35,000μgg−1, with individual concentrations exceeding 200,000μgg−1 in several cases. Median concentrations of Cu and Zn ranged from about 50 to 1900μgg−1 and 50 to 10,000μgg−1, respectively, with respective maxima of 172,000μgg−1 and 239,000μgg−1. Because of peeling paint, local sediment (analysed by ICP following acid digestion) was often measurably contaminated by the metals and, based on median, Al-normalised enrichment factors, in the order Pb>Zn>Cu. Due to its abundance and persistence in old paints, Pb is of greatest concern from both environmental and human health perspectives.

Identification of environmental sources of lead exposure in Nunavut (Canada) using stable isotope analyses

BackgroundBlood lead levels (BLLs) were measured in the adult Inuit population of Nunavut, Northern Canada, during the Inuit Health Survey (IHS) in 2007–2008. Approximately 10% of the adult participants had BLL over the Health Canada's guidance of 100μg/L. Objectives1) To repeat the measurement of BLL among the IHS participants with high BLL and household members including pregnant women and children under 10years of age; 2) to measure lead (Pb) concentrations in environmental samples to identify potential sources and 3) to explore how Pb from environmental samples contributes to BLL using Pb stable isotopic analyses. MethodsBlood samples were collected from 100 adults and 56 children in 2012. A total of 169 environmental samples (tap water, house dust, paint, country food, soil, and ammunition) were collected from 14 houses from three communities where the IHS participants had the highest BLL. Total Pb concentrations and Pb isotope mass balance were determined by inductively coupled plasma-mass spectrometry (ICP-MS). ResultsThe geometric mean of BLL was 43.1μg/L; BLL increased with age and was higher in adults than children (71.1 vs. 17.5μg/L). Median Pb concentrations in water (1.9μg/L) and dust (27.1μg/m2 for wiped dust, 32.6mg/kg for vacuum dust coarse fraction, and 141.9mg/kg for vacuum dust fine fraction) were generally higher than in other parts of Canada. Median Pb concentrations of food and soil coarse and fine fractions were low (36.6μg/kg, 5.4mg/kg and 11.8mg/kg respectively); paint chips exceeded the Canadian guidelines in two houses (median: 3.8mg/kg). Discriminant analyses and isotope ratio analyses showed that ammunition and house dust are major sources of Pb in this study population. ConclusionAnalyses of Pb stable isotopes are useful to identify the routes of exposure to Pb. This approach can contribute to develop targeted public health programmes to prevent Pb exposure.

Contemporary lead concentration and stable lead isotope ratio distribution in forest moss across the Czech Republic

Lead concentrations and stable lead isotopes (204Pb, 206Pb, 207Pb, 208Pb) were measured in forest moss samples (Pleurozium schreberi or Scleropodium purum) collected at 273 sites across the Czech Republic during 2010. Continuously decreasing median Pb concentrations in moss were documented over the last two decades: 1995: 11mg/kg, 2000: 5.66mg/kg, 2005: 4.94mg/kg and 2010: 2.85mg/kg. Several local anomalies have decreased in scale, the overall regional distribution patterns remained, however, the same. The regional Pb isotope ratio distributions show that the ratios show little variation for a large central part of the country and provide the large-scale background isotope ratios for the Czech Republic of about 204Pb/206Pb=0.0550, 206Pb/207Pb=1.167, 206Pb/208Pb=0.478 and 207Pb/208Pb=0.409 for 2010. This background Pb isotope ratio signal in moss has been locally (900–7500km2) modified by specific Pb isotopic ratio signals caused by deposition of Pb emissions from known local anthropogenic Pb emission sources, such as industrial combustion of local coal, and a variety of industrial enterprises (metallurgical, engineering and glass works). At some sites where mining of uranium and polymetallic ores took place the moss samples show also a locally specific Pb isotope signal. The in terms of area affected largest deviations in the Pb-isotope ratios, e.g., in the Bohemian Massif, may be due to the input of geogenic dust.

Assessment of metal contamination in sediments in the tributaries of the Euphrates River, using pollution indices and the determination of the pollution source, Turkey

The study area is located between 428120N latitude and 510760E longitude. The collected samples were vertical (sandbar) and stream sediments along the Geli Stream bed. Total concentrations of metals in the sediments were determined to evaluate the level of contamination. The median concentrations of As, Cu, Pb, Zn, Ag, Ni, Co, Mn, Cd, Sb, Cr, Ti and Al exceeded the concentrations in normal/background granodioritic rocks. Sediment pollution assessment was carried out using contamination factor (CF), pollution load index (PLI), enrichment factor (EF) and geoaccumulation index (Igeo). The metal concentrations in the assessed sediment samples (Geli Stream and sandbar) were compared with consensus-based TEC and PEC values.The CF values for As, Cu, Ni, Co and Cr >10 in sediments in the Geli Stream denote very high contamination by these metals. The PLI value indicated that the Geli Stream was moderately polluted. The highest Igeo values of Sb and Cr were found to be extremely polluted in sediments. The highest EF values of Sb, As and Cr were above 50, indicating extremely severe enrichment. Ecotoxicological indices (SQG) were used to assess the contamination levels of surface sediments. In this study, As and Cu in stream sediments were determined to be heavily polluted (37.95ppm and 85.12ppm; and Cr moderately polluted (64.50ppm). Moreover, heavy metal concentrations were assessed from the sediment samples and were compared with consensus-based PEL, TEL, LEL, MET, ERL, PEC and TEC values.In the Geli Stream sediments, As, Ba, Cr, Cu, Pb, Ni and Zn were higher than all these consensus-based values. In the sandbar, As and Cu values were higher than TEL, LEL, MET and TEC values, and Ba values were higher than PEC and TEC values. Anomaly maps were drawn on the drainage networks according to pollutant elements. This indicated that the possible source of pollution was located northeast of the study area. Pollution contributed to the geochemical prospection studies and was determined as a possible mineralization setting. Element distribution in the direction of the stream flow path was assessed by factor analysis. The factor analysis indicated that source of metals are derived from both lithologic units and mineralizations.

Hazardous waste characterization among various thermal processes in South Korea: A comparative analysis

Ministry of Environment, Republic of Korea (South Korea) is in progress of converting its current hazardous waste classification system to harmonize it with the international standard and to set-up the regulatory standards for toxic substances present in the hazardous waste. In the present work, the concentrations along with the trend of 13 heavy metals, F−, CN− and 19 PAH present in the hazardous waste generated among various thermal processes (11 processes) in South Korea were analyzed along with their leaching characteristics. In all thermal processes, the median concentrations of Cu (3.58–209,000mg/kg), Ni (BDL–1560mg/kg), Pb (7.22–5132.25mg/kg) and Zn (83.02–31419mg/kg) were comparatively higher than the other heavy metals. Iron & Steel thermal process showed the highest median value of the heavy metals Cd (14.76mg/kg), Cr (166.15mg/kg) and Hg (2.38mg/kg). Low molecular weight PAH (BDL–37.59mg/kg) was predominant in sludge & filter cake samples present in most of the thermal processes. Comparatively flue gas dust present in most of the thermal processing units resulted in the higher leaching of the heavy metals.

A Preliminary Study on the Use of Meconium for the Assessment of Prenatal Exposure to Heavy Metals in Japan

In recent years, there has been increasing interest in the relevance of environmental pollution to children's health. We investigated whether the concentrations of heavy metals in meconium can be used for the assessmet of prenatal exposure in Japan. Our study subjects were newborns whose mothers were hospitalized for childbirth at Tokai University Hospital between November 2010 and March 2011. The target compounds of this study were lead (Pb), cadmium (Cd) and arsenic (As). Meconium samples collected from 102 newborns were analyzed using ICPMS. The median concentrations of Pb and As in the meconium were 0.71 ppb and 0.03 ppb, respectively. The median concentration of Cd was below the limit of quantification. These concentration values are much lower than those used in previous studies. Further study is needed to compare the concentrations of heavy metals in biological samples and to investigate the availability of meconium for the assessment of exposure to heavy metals during pregnancy.

Road Dust Lead (Pb) in Two Neighborhoods of Urban Atlanta, (GA, USA)

Road dust continues to be a major potential reservoir of Pb in the urban environment, and an important potential component of child Pb exposure. This study presents ICP-AES analyses of metals in 72 samples of road dust (<250 µm) collected in the urban core of Atlanta, Georgia. In the Downtown area, median Pb concentrations are ~63 mg/kg Pb, with high values of 278 mg/kg. For comparison, median Pb values in a nearby residential neighborhood (also in the urban core) were ~93 mg/kg, with a high of 972 mg/kg. Geospatial variability is high, with significant variation observed over tens to hundreds of meters. Spearman Rank Correlation tests suggest that Pb and other metals (Cu, Ni, V, Zn) are associated with iron and manganese oxide phases in the residential area, as reported in other cities. However, Pb in the Downtown area is not correlated with the others, suggesting a difference in source or transport history. Given these complexities and the expected differences between road dust and soil Pb, future efforts to assess exposure risk should therefore be based on spatially distributed sampling at very high spatial resolution.

Spatial distribution of lead and lead isotopes in soil B-horizon, forest-floor humus, grass (Avenella flexuosa) and spruce (Picea abies) needles across the Czech Republic

Abstract Lead concentrations were determined in samples of soil B-horizon ( N = 258), forest-floor humus (O-horizon, N = 259), grass ( Avenella flexuosa , N = 251) and spruce ( Picea abies , N = 253) needles (2nd year) collected at the same locations evenly spread over the territory of the Czech Republic at an average density of 1 site/300 km 2 . Median Pb concentrations differ widely in the four materials: soil B-horizon: 27 mg/kg (3.3–220 mg/kg), humus: 78 mg/kg (19–1863 mg/kg), grass: 0.37 mg/kg (0.08–8 mg/kg) and spruce needles: 0.23 mg/kg (0.07–3 mg/kg). In the Pb distribution maps for humus, grass and spruce a number of well-known Pb-contamination sources are indicated by unusually high concentrations (e.g., the Pb smelter at Pribram, the metallurgical industry in the NE of the Czech Republic and along the Polish border, as well as the metallurgical industry in Upper Silesia and Europe’s largest coal-fired power plant at Bogatynia, Poland). The ratio 206 Pb/ 207 Pb was determined in all four materials. The median value of the 206 Pb/ 207 Pb isotope ratio in the soil B-horizon is 1.184 (variation: 1.145–1.337). In both humus and grass the median value for the 206 Pb/ 207 Pb isotope ratio is 1.162 (variation: 1.130–1.182), in spruce needles the median ratio is 1.159 (variation: 1.116–1.186). In humus, grass and spruce needles the known contamination sources are all marked by higher 206 Pb/ 207 Pb isotope ratios in the maps. Furthermore, the soil B-horizon, humus, grass and spruce needles show distinctly different spatial distribution patterns of the 206 Pb/ 207 Pb isotope ratios. The B-horizon does not provide a viable background value for metal concentrations in the O-horizon or plant materials. None of the maps provides evidence for the importance of traffic-related emissions for the observed isotope ratios at the scale of the Czech Republic.

Breast milk lead and cadmium levels from suburban areas of Ankara

The objectives of this study were (1) to evaluate levels of lead (Pb) and cadmium (Cd) in the breast milk at 2 months postpartum, (2) to investigate the relationship between Pb and Cd levels in breast milk and some sociodemographic parameters and (3) to detect whether these levels have any influence on the infant's physical status or on postpartum depression in the mothers. Pb and Cd levels in breast milk were determined by Inductively Coupled Plasma Mass Spectroscopy (ICP-MS). The median breast milk concentrations of Pb and Cd were 20.59 and 0.67 μg/l, respectively. In 125 (87%) of 144 samples, Pb levels were higher than the limit in breast milk reported by the World Health Organization (WHO) (> 5 μg/l). Breast milk Cd levels were > 1 μg/l in 52 (36%) mothers. The mothers with a history of anemia at any time had higher breast milk Pb levels than those without a history of anemia (21.1 versus 17.9 μg/l; p = 0.0052). The median breast milk Cd levels in active and passive smokers during pregnancy were significantly higher than in non-smokers (0.89, 0.00 μg/l, respectively; p = 0.023). The breast milk Cd levels of the mothers who did not use iron and vitamin supplements for 2 months postpartum were found to be higher than in those who did use the supplements (iron: 0.73, 0.00 μg/l, p = 0.023; vitamin: 0.78, 0.00 μg/l, p = 0.004, respectively). Breast milk Cd levels at the 2nd month were correlated negatively with the z scores of head circumference and the weight for age at birth (r = − 0.257, p = 0.041 and r = − 0.251, p = 0.026, respectively) in girls. We found no correlation between the breast milk Pb and Cd levels and the Edinburgh Postpartum Depression Scale scores. Breast milk monitoring programs should be conducted that have tested considerable numbers of women over time in view of the high levels of Pb in breast milk in this study.

Determination of Lead in Croatian Wines by Graphite Furnace Atomic Absorption Spectrometry

A method has been developed for direct determination of lead in wine by graphite furnace atomic absorption spectrometry (GFAAS) with Zeeman-effect background correction. The thermal behaviour of Pb during pyrolysis and atomisation stages was investigated without matrix modifier and in the presence of Pd(NO(3))(2), Pd(NO(3))(2) + Mg(NO(3))(2) × 6H(2)O, and NH(4)H(2)PO(4) + Mg(NO(3))(2) × 6H(2)O as matrix modifiers. A simple 1:1 dilution of wine samples with Pd(NO3)2 as a matrix modifier proved optimal for accurate determination of Pb in wine. Mean recoveries were 106 % for red and 114 % for white wine, and the detection limit was 3 μg L(-1). Within-run precision of measurements for red and white wine was 2.1 % and 1.8 %, respectively. The proposed method was applied for analysis of 23 Croatian wines. Median Pb concentrations were 33 μg L(-1), range (16 to 49) μg L(-1) in commercially available wines and 46 μg L(-1), range (14 to 559) μg L(-1) in home-made wines. There were no statistically significant differences (P<0.05) in Pb concentration between commercial and home-made wines or between red and white wines.

Toxic Metals (Pb and Cd) and Their Respective Antagonists (Ca and Zn) in Infant Formulas and Milk Marketed in Brasilia, Brazil

In non-ideal scenarios involving partial or non-breastfeeding, cow’s milk-based dairy products are mainstream in infant feeding. Therefore, it is important to study the concentrations of potentially neurotoxic contaminants (Pb and Cd) and their respective counteracting elements (Ca and Zn) in infant dairy products. Fifty-five brands of infant formulas and milk sold in Brasilia, Brazil were analyzed. The dairy products came from areas in the central-west (26%), southeast (29%) and south of Brazil (36%) extending as far as Argentina (7%) and the Netherlands (2%). For toxic Pb and Cd, median concentrations in powdered samples were 0.109 mg/kg and 0.033 mg/kg, respectively; in fluid samples median Pb concentration was 0.084 mg/kg, but median Cd concentration was below the limit of detection and overall values were below reference safety levels. However, 62% of these samples presented higher Pb concentration values than those established by FAO/WHO. Although the inverse correlation between Cd and Zn (Spearman r = −0.116; P = 0.590) was not statistically significant, the positive correlation between Ca and Pb was (Spearman r = 0.619; P < 0.0001). Additionally, there was a significant correlation between Pb and Cd. Furthermore, the study also revealed that provision of the essential trace element Zn in infant formulas can provide adequate amounts of the recommended daily requirements. Infant formulas and milk sold for consumption by infants and children can be an efficient tool to monitor neurotoxic metal risk exposure among young children.

Assessment of soil contamination by potentially toxic elements in the aljustrel mining area in order to implement soil reclamation strategies

AbstractLand pollution due to past mining activities is a major environmental issue in many European countries. The Aljustrel mine (SW Portugal), located in the western sector of the Iberian Pyrite Belt (IBP) presents a negative visual and environmental impact as a consequence of the mining activity that has developed since the Roman era. Its impacts are also a restraint on the life quality of the population. The exposure of pyrite and other sulphides to air are responsible for the pollution observed in soils, surface water and stream sediments. This paper investigates the pollution load of potential toxic elements in soil samples collected around the Aljustrel mining area. The aim is to assess the levels of soil contamination with respect to average concentrations of toxic elements in the region and to understand the partitioning and availability of pollutants in the area.The results showed severe soil contamination (mainly As, Cd, Cu, Pb and Zn). The concentrations of As (up to 3936 mg kg−1) and certain heavy metals (up to 5414 mg kg−1Cu, 61·6 mg kg−1Cd, 20 000 mg kg−1Pb and 20 000 mg kg−1Zn) are two orders of magnitude above the regional South Portuguese Zone (SPZ) background values. The median concentrations of As, Cd, Cu, Pb and Zn exceed the values established for world soils, the European Union, Portugal and Andalusia. The results suggest that the distribution patterns of Co, Cr and Ni element concentrations in the Aljustrel area are primarily influenced by the lithology and geochemistry nature of bedrock. The soil background of this geological domain is characterized by relatively high heavy metal contents, essentially derived from the parent rocks. Copyright © 2010 John Wiley &amp; Sons, Ltd.