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Lead Exposure (lead + exposure)
Kinds of Lead Exposure Selected AbstractsEffect of Maternal Lead Exposure on Craniofacial Ossification in Rat Fetuses and the Role of Antioxidant TherapyANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 5 2009H. A. Saleh Summary Lead exposure during intrauterine life was found to result in reduced birth weight, impaired skeletal development and post-natal neurotoxic effects. In this study, the effect of pre-natal exposure to different doses of lead on the development of craniofacial skeleton in rat fetuses was investigated. Vitamin E was tested as a concomitant treatment, aiming to improve the fetotoxic effects of lead. Positively pregnant female rats were randomly divided into four groups; groups I and II (L250 and L500), exposed to lead acetate in doses of 250 and 500 mg/l respectively, group III (L500 + E), exposed to lead acetate (500 mg/l) wit concomitant vitamin E and group IV (Control) which was given sodium acetate only. All the treatments started from the first day of gestation till the 20th day, where all rats were sacrificed and the fetuses were recovered. Fetuses were processed to alizarin red staining for ossified components. Twenty-seven bones of the craniofacial skeleton were studied in each fetus where the ossification was scored as being complete, delayed or absent. In all studied fetuses from all groups, changes were found only in eight bones while the remaining craniofacial bones were normally ossified. In affected bones there was a significant decrease in the number of completely ossified bones; associated with a significant increase of both partially ossified and absent bones in L250 and L500 treated groups when compared to the control group. These differences were more significant in the L500 treated group. Giving vitamin E improved the percentage of completely ossified craniofacial bones and decreased the percentage of both partially ossified and absent bones. The most affected bone was presphenoid, then to a lesser extent supraoccipital, squamosal, parietal, interparietal and frontal bone respectively. In conclusion, lead exposure to rats during pregnancy led to varying degrees of fetal growth retardation as well as delayed ossification of some craniofacial bones which were dose dependent and the concomitant supplementation with vitamin E greatly improved the deleterious effect of lead. [source] Lead accumulation in feathers of nestling black-crowned night herons (Nycticorax nycticorax) experimentally treated in the fieldENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 7 2003Nancy H. Golden Abstract Although lead can attain high concentrations in feathers, interpretation of the biological significance of this phenomenon is difficult. As part of an effort to develop and validate noninvasive methods to monitor contaminant exposure in free-ranging birds, lead uptake by feathers of nestling black-crowned night herons (Nycticorax nycticorax) was evaluated in a controlled exposure study. Four- to 6-d-old heron nestlings (one/nest) at Chincoteague Bay, Virginia (USA), received a single intraperitoneal injection of dosing vehicle (control, n = 7) or a dose of lead nitrate in water (0.01, 0.05, or 0.25 mg Pb/g body wt of nestling; n = 6 or 7/dose) chosen to yield feather lead concentrations found at low- to moderately polluted sites. Nestlings were euthanized at 15 d of age. Lead accumulation in feathers was associated with concentrations in bone, kidney, and liver (r = 0.32,0.74, p < 0.02) but exhibited only modest dose dependence. Blood delta-aminolevulinic acid dehydratase activity was inhibited by lead, although effects on other biochemical endpoints were marginal. Tarsus growth rate was inversely related to feather lead concentration. Culmen growth rate was depressed in nestlings treated with the highest dose of lead but not correlated with feather lead concentration. These findings provide evidence that feathers of nestling herons are a sensitive indicator of lead exposure and have potential application for the extrapolation of lead concentrations in other tissues and the estimation of environmental lead exposure in birds. [source] Lead and cadmium uptake in the marine fungi Corollospora lacera and Monodictys pelagicaFEMS MICROBIOLOGY ECOLOGY, Issue 3 2005Michael A.S. Taboski Abstract This study provides observations on the effects of lead and cadmium ions on the growth of two species of marine fungi, Corollospora lacera and Monodictys pelagica. On solid media lead appeared to have no effect on the radial rate of growth of fungi. Exposure to increasing cadmium concentrations on solid media resulted in significant reduction (P < 0.05) in the radial mycelial growth rates of both fungi, especially in M. pelagica. These results reveal significant difference in species sensitivity toward cadmium and, essentially, insensitivity toward lead exposure. In liquid cultures, the metal content of mycelia (metal mass found in mycelium, in mg), and the concentration of metal in dry mycelium (metal mass in 1 g of mycelium, in mg g,1) were both found to increase (P < 0.05) with the increase in the metal cation concentration, while mycelium dry mass decreased. As it was observed on solid media, cadmium cation affected more severely (P < 0.05) the growth of M. pelagica in liquid cultures. Ergosterol content of mycelia of C. lacera exposed to increasing cadmium cation concentration decreased, similarly to the trend observed for dry mycelial mass. It was found that ca. 93% of all lead sequestered by C. lacera is located extracellularly. M. pelagica was found to bioaccumulate over 60 mg of cadmium and over 6 mg of lead per 1 g of mycelium, while C. lacera bioaccumulated over 7 mg of cadmium and up to 250 mg of lead per 1 g of mycelium. Overall, the results indicate that both metal ions affect the growth of marine fungi with lead being accumulated extracellularly in the mycelia. Both metals accumulated by fungi may then enter the marine ecosystem food web, of which marine fungi are integral members. [source] Brain cancer mortality and potential occupational exposure to lead: Findings from the National Longitudinal Mortality Study, 1979,1989INTERNATIONAL JOURNAL OF CANCER, Issue 5 2006Edwin van Wijngaarden Abstract We evaluated the association between potential occupational lead exposure and the risk of brain cancer mortality in the National Longitudinal Mortality Study (NLMS), which is a prospective census-based cohort study of mortality among the noninstitutionalized United States population (1979,1989). The present study was limited to individuals for whom occupation and industry were available (n = 317,968). Estimates of probability and intensity of lead exposure were assigned using a job-exposure matrix (JEM). Risk estimates for the impact of lead on brain cancer mortality were computed using standardized mortality ratio (SMR) and proportional hazards and Poisson regression techniques, adjusting for the effects of age, gender and several other covariates. Brain cancer mortality rates were greater among individuals in jobs potentially involving lead exposure as compared to those unexposed (age- and gender-adjusted hazard ratio (HR) = 1.5; 95% confidence interval (CI) = 0.9,2.3) with indications of an exposure,response trend (probability: low HR = 0.7 (95% CI = 0.2,2.2), medium HR = 1.4 (95% CI = 0.8,2.5), high HR = 2.2 (95% CI = 1.2,4.0); intensity: low HR = 1.2 (95% CI = 0.7,2.1), medium/high HR = 1.9 (95% CI = 1.0,3.4)). Brain cancer risk was greatest among individuals with the highest levels of probability and intensity (HR = 2.3; 95% CI = 1.3,4.2). These findings provide further support for an association between occupational lead exposure and brain cancer mortality, but need to be interpreted cautiously due to the consideration of brain cancer as one disease entity and the absence of biological measures of lead exposure. © 2006 Wiley-Liss, Inc. [source] Teeth and blood lead levels in egyptian schoolchildren: relationship to health effectsJOURNAL OF APPLIED TOXICOLOGY, Issue 4 2001Magdy Omar Abstract The objective of this work was to study teeth and blood lead levels in Egyptian schoolchildren and to relate lead levels to sociodemographic and environmental factors, the degree of urbanization and suspected manifestations of possible lead exposure. The study was conducted on 60 children aged 6,12 years: 30 children living in an urban area at Alexandria City and 30 children living in a rural area at Kafr El-Sheikh Province. Both groups are matched for age and gender. Every child was subjected to history taking, clinical examination and IQ measurements. Laboratory investigations included measuring teeth and blood lead levels, haemoglobin, serum iron and total iron binding capacity. The results showed that the mean blood lead level of children in Alexandria was significantly higher than that of the children in Kafr El-Sheikh; also 56.7% and 6.7% of children from Alexandria and Kafr El-Sheikh had a blood lead level of >20 µg dl,1, with the most frequent symptoms of headache, arthralgia and lack of school interest. The children in Alexandria had significantly lower mean teeth lead and haemoglobin levels than those of the Kafr El-Sheikh group. A history of wrapping sandwiches in newspapers, age and distance between the home and school were significant predictors of lead exposure. These findings support the concept that teeth lead concentration may be a valid addition to the indicators used for assessment of the body burden of environmental lead. In addition, children living in urban areas such as Alexandria need special consideration regarding protection from lead exposure, as well as teeth and blood lead evaluation. Copyright © 2001 John Wiley & Sons, Ltd. [source] Lead-induced alterations of apoptosis and neurotrophic factor mRNA in the developing rat cortex, hippocampus, and cerebellumJOURNAL OF BIOCHEMICAL AND MOLECULAR TOXICOLOGY, Issue 5 2007Shirley L. Chao Abstract Previous reports have recently shown the prototypic neurotoxicant, lead, to induce apoptosis in the brains of developing organisms. In the current study, timed-pregnant rats were exposed to lead acetate (0.2% in the drinking water) 24 h following birth at postnatal day 1 (PND 1). Dams and pups were continuously exposed to lead through the drinking water of the dam until PND 20. Postnatal exposure in the pups resulted in altered mRNA levels of the following apoptotic and neurotrophic factors: caspase 2 and 3, bax, bcl-x, brain-derived neurotrophic factor (BDNF). Ribonuclease protection assays were conducted to measure the factors simultaneously at the following postnatal time points: 9, 12, 15, 20, 25, days. Our results suggest a brain region- and time-specific response following lead acetate exposure. The region most vulnerable to alterations occurs in the hippocampus with alterations beginning at PND 12, in which caspase 3, bcl-x, BDNF increase with lead exposure. Significant treatment effects were not observed for both the cortex and cerebellum. © 2007 Wiley Periodicals, Inc. J Biochem Mol Toxicol 21:265,272, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jbt.20191 [source] Low-level lead exposure and childrenJOURNAL OF PAEDIATRICS AND CHILD HEALTH, Issue 5 2001NR Wigg Abstract: The adverse effects of environmental lead exposure on the mental development of young children are well established. There is no safe level of blood lead below which children are not affected. Recent research expands our understanding of the impact of lead exposure continuing into later childhood, as well as its effects on children's behaviour. However, social and other environmental factors also contribute to variance in measures of developmental and behavioural outcomes. Lead is associated with only modest effects on children's development, but is a potentially modifiable risk factor. As environmental exposure to lead declines for the whole population, continued specific attention is needed for children living in industrial areas. [source] The effect of adding cadmium and lead alone or in combination to the diet of pigs on their growth, carcase composition and reproductionJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 13 2003Clive Phillips Abstract Limits for cadmium and lead concentrations in food animal products have been established independently, whereas these two toxic metals often co-exist in polluted regions. Weaned pigs (60) were allocated to ten treatments: control; low (0.5 mg kg,1), medium (1 mg kg,1) or high cadmium (2.5 mg kg,1) in feed; low (5 mg kg,1) medium (10 mg kg,1) or high (25 mg kg,1) lead in feed; and low, medium and high cadmium plus lead in feed. Growth rates and concentrations of cadmium and lead in body tissues (kidney, liver, spleen, lungs, heart, testicle, ribs, hair and teeth) were measured after 137 days. There was a similar reduction in weight gain for pigs in the cadmium and lead treatments, compared with the control, and a greater reduction for the pigs in the cadmium plus lead treatments. The reduction increased with the level of metal included. There was an increase in cadmium concentration of all tissues and blood with increasing feed cadmium concentration, which was usually less when lead was also included in the feed. There was also an increase in tissue lead concentration with increasing dietary lead, and this was in most cases increased when cadmium was also included in the feed. The most sensitive tissues for cadmium and lead exposure were the kidney, liver, hair and teeth, and regression equations were developed for the accumulation rates in these tissues. Tissue and blood cadmium concentrations increased gradually with increasing dietary lead, whereas tissue lead concentration was not sensitive to dietary cadmium, except in the ribs and heart. In a second experiment, 10 sows were allocated to a control diet or the same diet but with a supplement of cadmium and lead. The birth weight of piglets was decreased by the supplement and their mortality increased. Lead accumulated most in the ovary and oviduct of the sows, and there were increases in the lead and, to a lesser extent, cadmium concentrations of tissues of the piglets from these sows. Copyright © 2003 Society of Chemical Industry [source] Parental exposure to lead and small for gestational age birthsAMERICAN JOURNAL OF INDUSTRIAL MEDICINE, Issue 6 2006Pau-Chung Chen MD Abstract Background Previous studies about the effect of lead exposure on adverse birth outcomes are still inconsistent and few studies estimate the relationship between parental lead exposure and small for gestational age (SGA) infants. An occupational cohort study to assess whether parental lead exposure would be related to decreased birth weight and shortened gestational ages of their offspring was conducted. Whether higher lead exposure doses would increase risks of low birth weight (LBW), preterm delivery, and SGA births was also investigated. Methods A Program to Reduce Exposure by Surveillance System,Blood Lead Levels (Press-BLLS) was established in Taiwan in July 1993. The names of workers exposed to lead was collected from this occupational blood-lead notification database. The birth outcomes of their offspring were determined by linking to the Taiwan birth registration database from 1993 to 1997. Only singleton births whose parental blood-lead concentrations were tested during pregnancy or prior to conception, or within a 1-year span before these two periods were included. Results Among 1,611 eligible births, 72 births were LBW, 74 were preterm deliveries, and 135 were SGA. Maternal blood-lead concentrations (PbBs) equal to or more than 20 µg/dl had a higher risk of mothering a SGA child (risk ratio (RR),=,2.15; 95% confidence interval (CI), 1.15,3.83). Conclusions Additional evidence of the effects of lead on adverse birth outcomes, especially for SGA births is reported. Maternal exposure to lead plays a more important role in the adverse effect on birth outcome than does paternal exposure. Am. J. Ind. Med. 2006. © 2006 Wiley-Liss, Inc. [source] Plasma-lead concentration: Investigations into its usefulness for biological monitoring of occupational lead exposureAMERICAN JOURNAL OF INDUSTRIAL MEDICINE, Issue 2 2006Ingvar A. Bergdahl Abstract Background The lead concentration in plasma is correlated to that in whole blood with a two to fourfold variation. It has never been investigated if this variation is inter-individual. Methods Lead and hemoglobin were determined in blood and plasma from 13 lead workers with a history of relatively high blood-lead concentrations, sampled three times during 1 day. The variation in the distribution of lead between cells and plasma was studied, but not the variation in the lead concentrations as such. Results Blood hemoglobin decreased with rising plasma lead (0.9,3.0 µg/L). Regarding the distribution of lead, no effect of current exposure during the day or of recent meals appeared. As much as 84% of the overall variance of the distribution of lead between cells and plasma could be attributed to individual factors. After adjustment for erythrocyte volume fraction this decreased to 67%. Plasma samples with elevated hemoglobin concentrations (due to in vitro hemolysis) had somewhat elevated lead concentrations. Conclusions Plasma lead is not significantly altered by variation in a single day's exposure and, therefore, the choice of time of the day is not critical for sampling. However, plasma lead is negatively correlated to blood hemoglobin and mild hemolysis (not visible by the eye) in a sample may increase plasma lead with up to 30%. Finally, plasma provides lead exposure information that differs from whole blood, but it is not clear which one of these is the biomarker with the closest relation to exposure and/or effects. Am. J. Ind. Med. 49:93,101, 2006. © 2006 Wiley-Liss, Inc. [source] Association between bone lead concentration and blood pressure among young adultsAMERICAN JOURNAL OF INDUSTRIAL MEDICINE, Issue 2 2002Fredric Gerr MD Abstract Background Occupational and environmental exposure to lead has been examined for its effect on blood pressure (BP) in adults with varying results. The present analyses assessed the association between bone lead concentration and BP in early adult life in persons exposed during childhood. Methods Study participants included young adult members of two cohorts with different past histories of lead exposure. Lead exposure was assessed using noninvasive K-X-ray fluorescence spectroscopy to quantify bone lead concentration, an index of long-term lead exposure superior to current blood lead concentration. Systolic and diastolic BP measurements were obtained using conventional clinical methods. Multiple linear regression models were constructed to allow for control of covariates of BP identified a priori. Results Analyses were performed on 508 participants. While controlling for potential confounders, systolic BP was 4.3 mm,Hg greater among members of the highest of four bone lead concentration groups (>,10 ,gPb/g bone) when compared with the lowest bone lead concentration group (<,1 ,gPb/g bone; P,=,0.004), and diastolic BP was 2.8 mm,Hg greater among members of the highest bone lead concentration group when compared with the lowest bone lead concentration group (P,=,0.03). Conclusions These results suggest that substantial lead exposure during childhood can increase BP during young adulthood. Am. J. Ind. Med. 42:98,106, 2002. © 2002 Wiley-Liss, Inc. [source] A pilot evaluation of tibia lead concentrations in TaiwanAMERICAN JOURNAL OF INDUSTRIAL MEDICINE, Issue 2 2001Andrew C. Todd Abstract Background The aims of this study were to examine some of the factors that influence tibia lead concentrations, tibia lead x-ray fluorescence measurement uncertainty and blood lead concentrations, and to compare tibia lead concentrations in Taiwanese lead workers to those observed in lead workers from other countries. Methods A pilot evaluation of 43 adult lead workers who underwent measurements of tibia lead and blood lead concentrations. Results Mean and maximum tibia lead concentrations were 54 ,g of Pb per g of bone mineral(,g/g) and 193 ,g/g, respectively. Mean and maximum blood lead concentrations were 44 ,g/dl and 92 ,g/dl, respectively. Conclusion Past occupational control of lead exposure in Taiwan, ROC, did not prevent these workers from accumulating tibia lead concentrations greater than those in similar workers elsewhere in the world. Am. J. Ind. Med. 40:127,132, 2001. © 2001 Wiley-Liss, Inc. [source] Environmental enrichment reverses cognitive and molecular deficits induced by developmental lead exposureANNALS OF NEUROLOGY, Issue 1 2003Tomás R. Guilarte PhD Long-term deficits in cognitive function are the principal effects of lead (Pb2+) exposure in children and can be modeled in experimental animals. Current therapeutic approaches in the treatment of childhood Pb2+ intoxication are not effective in reversing learning deficits once they have occurred. We report that environmental enrichment reverses long-term deficits in spatial learning produced by developmental Pb2+ exposure in rats. Enhanced learning performance of Pb2+ -exposed animals reared in an enriched environment was associated with recovery of deficits in N- methyl- D -aspartate receptor subunit 1 (NR1) mRNA and induction of brain-derived neurotrophic factor (BDNF) mRNA in the hippocampus. The effect of environmental enrichment on NR1 and BDNF gene expression was specific to Pb2+ -exposed animals and was present in the absence of changes in the NR2B subunit of the N- methyl- D -aspartate receptor, GluR1, ,CamKII, or PSD-95 gene expression measured in the same animals. Our findings demonstrate that the learning impairments and NR1 subunit mRNA deficits resulting from developmental Pb2+ exposure are reversible if the animals are provided with an enriched environment even after the exposure has occurred. We propose environmental enrichment as a basis for the treatment of childhood Pb2+ intoxication. [source] Residual-Based Diagnostics for Structural Equation ModelsBIOMETRICS, Issue 1 2009B. N. Sánchez Summary Classical diagnostics for structural equation models are based on aggregate forms of the data and are ill suited for checking distributional or linearity assumptions. We extend recently developed goodness-of-fit tests for correlated data based on subject-specific residuals to structural equation models with latent variables. The proposed tests lend themselves to graphical displays and are designed to detect misspecified distributional or linearity assumptions. To complement graphical displays, test statistics are defined; the null distributions of the test statistics are approximated using computationally efficient simulation techniques. The properties of the proposed tests are examined via simulation studies. We illustrate the methods using data from a study of in utero lead exposure. [source] Parental lead exposure and total anomalous pulmonary venous returnBIRTH DEFECTS RESEARCH, Issue 4 2004Leila W. Jackson Abstract BACKGROUND Investigators from the Baltimore-Washington Infant Study (BWIS) reported an association between self-reported maternal lead exposure and total anomalous pulmonary venous return (TAPVR) in their offspring. This association was further evaluated in the BWIS population using a more sensitive exposure estimate. METHODS Cases included 54 live-born infants with TAPVR; controls were a stratified random sample of 522 live-born infants from the BWIS control group. Parental lead exposure was based on three assessment methods, including: an industrial hygiene assessment, an a priori job exposure matrix, and self-reported exposures. A parent was classified as exposed to lead if he/she was classified as exposed by any one of the assessment methods. RESULTS Approximately 17% of case mothers and 11% of control mothers were classified as exposed to lead during the three months prior to conception through the first trimester (odds ratio [OR], 1.57; 95% confidence interval [CI], 0.64,3.47). Among fathers, 61% of case fathers and 46% of control fathers were classified as exposed to lead during the six months prior to conception (paternal critical period) (OR, 1.83; 95% CI, 1.00,3.42). During the paternal critical period, when only the father was exposed compared to neither parent exposed, the OR for any lead exposure and TAPVR was 1.65 (95% CI, 0.84,3.25). CONCLUSIONS This study supports a possible association between paternal lead exposure and TAPVR. Further studies are warranted using validated assessment methods for occupational and nonoccupational lead exposures to corroborate this association and to elucidate the possible biological mechanism. Birth Defects Research (Part A), 2004. © 2004 Wiley-Liss, Inc. [source] Blood lead levels in Egyptian children from high and low lead-polluted areas: impact on cognitive functionACTA NEUROLOGICA SCANDINAVICA, Issue 1 2009G. A. Mostafa Objectives,,, Many children are harmed by low-level lead exposure which impairs cognitive development with subsequent poor scholastic achievement. We investigated blood lead levels in children in relation to cognitive function. Materials and methods,,, Blood lead levels were measured in 100 children recruited from high (n = 50) and low (n = 50) lead-polluted areas. Results,,, Blood lead levels ranged between 3 and 28 ,g/dl (median 9, interquartile range 6 ,g/dl). In addition, 43% of children had levels ,10 ,g/dl, of whom 90.1% were living in high-risk areas for lead pollution. Cognitive dysfunction was found in 37% of children. Children with cognitive dysfunction had significantly higher blood lead and lower hemoglobin than those without (P < 0.001). Conclusions,,, Increased blood lead level in many children is one of the health problems in Egypt which may be the reason, at least in part, for cognitive dysfunction with subsequent poor scholastic achievement. Thus, interventions to control lead exposure are mandatory. [source] Burden of disease attributable to selected environmental factors and injury among children and adolescents in EuropeCHILD: CARE, HEALTH AND DEVELOPMENT, Issue 6 2004Richard Reading Burden of disease attributable to selected environmental factors and injury among children and adolescents in Europe . ValentF, LittleD, BertolliniR, NemerLE, BarboneF & TamburliniG . ( 2004 ) Lancet , 363 , 2032 , 2039 . Background Environmental exposures contribute to the global burden of disease. We have estimated the burden of disease attributable to outdoor and indoor air pollution, inadequate water and sanitation, lead exposure, and injury among European children and adolescents. Methods Published studies and reports from international agencies were reviewed for calculation of risk-factor exposure in Europe. Disability-adjusted life years (DALYs) or deaths attributable to each factor, or both, were estimated by application of the potential impact fraction to the estimates of mortality and burden of disease from the WHO global database of burden of disease. Findings Among children aged 0,4 years, between 1.8% and 6.4% of deaths from all causes were attributable to outdoor air pollution; acute lower-respiratory-tract infections attributable to indoor air pollution accounted for 4.6% of all deaths and 3.1% of DALYs; and mild mental retardation resulting from lead exposure accounted for 4.4% of DALYs. In the age-group 0,14 years, diarrhoea attributable to inadequate water and sanitation accounted for 5.3% of deaths and 3.5% of DALYs. In the age-group 0,19 years, injuries were the cause of 22.6% of all deaths and 19.0% of DALYs. The burden of disease was much higher in European subregions B and C than subregion A. There was substantial uncertainty around some of the estimates, especially for outdoor air pollution. Interpretation Large proportions of deaths and DALYs in European children are attributable to outdoor and indoor air pollution, inadequate water and sanitation, lead exposure, and injuries. Interventions aimed at reducing children's exposure to environmental factors and injuries could result in substantial gains. The pronounced differences by subregion and age indicate the need for targeted action. [source] INTERPLAY OF REACTIVE OXYGEN SPECIES AND NITRIC OXIDE IN THE PATHOGENESIS OF EXPERIMENTAL LEAD-INDUCED HYPERTENSIONCLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY, Issue 9 2007ND Vaziri SUMMARY 1Lead is a common environmental and industrial toxin that can cause a variety of acute and chronic illnesses. For example, chronic exposure to low levels of lead has been shown to raise arterial pressure and promote renal and cardiovascular complications. 2Several mechanisms have been identified by which chronic lead exposure can cause hypertension and cardiovascular disease. In recent years, increasing evidence has emerged pointing to the role of oxidative stress as a major mediator of lead-induced hypertension. 3The present article provides an overview of the published studies on this subject. [source] Evaluation of a second-generation portable blood lead analyzer in an occupational settingAMERICAN JOURNAL OF INDUSTRIAL MEDICINE, Issue 12 2007Noel V. Stanton MS Abstract Background A new blood lead testing instrument has qualities that make the instrument attractive for on-site testing of occupational lead exposures. This study evaluated the accuracy of the instrument when used in a manufacturing setting, and examined the impact of blood storage and shipment on results. Methods Venous blood specimens (n,=,121) were obtained and immediately analyzed on-site using the new instrument. They were then shipped to a reference laboratory and analyzed using electro-thermal atomization atomic absorption spectrometry (ETAAS), and retested using the new instrument. Results The cohort blood lead concentration averaged 40.1 µg/dl. Results obtained on the new analyzer with freshly collected blood averaged 38.7 µg/dl. The mean difference of 1.2 µg/dl on paired samples was not statistically significant. Following blood shipment and storage, results on the analyzer increased to an average of 42.4 µg/dl. The mean increase of 3.0 µg/dl on stored blood samples also failed to reach statistical significance. Under OSHA proficiency test acceptability requirements, 94% of the results had satisfactory agreement. Conclusions The new analyzer might be a useful tool for on-site monitoring of occupational lead exposures. The manufacturer's instructions should be adhered to with respect to specimen age and storage requirements. Am. J. Ind. Med. 50:1018,1024, 2007. © 2007 Wiley-Liss, Inc. [source] Parental lead exposure and total anomalous pulmonary venous returnBIRTH DEFECTS RESEARCH, Issue 4 2004Leila W. Jackson Abstract BACKGROUND Investigators from the Baltimore-Washington Infant Study (BWIS) reported an association between self-reported maternal lead exposure and total anomalous pulmonary venous return (TAPVR) in their offspring. This association was further evaluated in the BWIS population using a more sensitive exposure estimate. METHODS Cases included 54 live-born infants with TAPVR; controls were a stratified random sample of 522 live-born infants from the BWIS control group. Parental lead exposure was based on three assessment methods, including: an industrial hygiene assessment, an a priori job exposure matrix, and self-reported exposures. A parent was classified as exposed to lead if he/she was classified as exposed by any one of the assessment methods. RESULTS Approximately 17% of case mothers and 11% of control mothers were classified as exposed to lead during the three months prior to conception through the first trimester (odds ratio [OR], 1.57; 95% confidence interval [CI], 0.64,3.47). Among fathers, 61% of case fathers and 46% of control fathers were classified as exposed to lead during the six months prior to conception (paternal critical period) (OR, 1.83; 95% CI, 1.00,3.42). During the paternal critical period, when only the father was exposed compared to neither parent exposed, the OR for any lead exposure and TAPVR was 1.65 (95% CI, 0.84,3.25). CONCLUSIONS This study supports a possible association between paternal lead exposure and TAPVR. Further studies are warranted using validated assessment methods for occupational and nonoccupational lead exposures to corroborate this association and to elucidate the possible biological mechanism. Birth Defects Research (Part A), 2004. © 2004 Wiley-Liss, Inc. [source] | |||||||||||||||||||