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Sample records for lead exposure stimulates

  1. Lead exposure stimulates VEGF expression in the spinal cord and extends survival in a mouse model of ALS

    PubMed Central

    Barbeito, Ana G.; Martinez-Palma, Laura; Vargas, Marcelo R.; Pehar, Mariana; Mañay, Nelly; Beckman, Joseph S.; Barbeito, Luis; Cassina, Patricia

    2009-01-01

    Exposure to environmental lead (Pb) is a mild risk factor for Amyotrophic Lateral Sclerosis (ALS), a paralytic disease characterized by progressive degeneration of motor neurons. However, recent evidence has paradoxically linked higher Pb levels in ALS patients with longer survival. We investigated the effects of low-level Pb exposure on survival of mice expressing the ALS-linked superoxide dismutase-1 G93A mutation (SOD1G93A). SOD1G93A mice exposed to Pb showed longer survival and increased expression of VEGF in the ventral horn associated with reduced astrocytosis. Pretreatment of cultured SOD1G93A astrocytes with low, non toxic Pb concentrations upregulated VEGF expression and significantly abrogated motor neuron loss in co-culture, an effect prevented by neutralizing antibodies to VEGF. The actions of Pb on astrocytes might explain its paradoxical slowing of disease progression in SOD1G93A mice and the improved survival of ALS patients. Understanding how Pb stimulates astrocytic VEGF production and reduces neuroinflammation may yield a new therapeutic approach for treating ALS. PMID:19914377

  2. Food Exposures to Lead

    PubMed Central

    Kolbye, Albert C.; Mahaffey, Kathryn R.; Fiorino, John A.; Corneliussen, Paul C.; Jelinek, Charles F.

    1974-01-01

    Exposures to lead have emanated from various sources, including food, throughout human history. Occupational and environmental exposures (especially pica) appear to account for much of the identified human disease, however, food-borne exposures deserve further investigation. Lead residues in food can result from: biological uptake from soils into plants consumed by food animals or man, usage of lead arsenate pesticides, inadvertent addition during food processing, and by leaching them improperly glazed pottery used as food storage or dining utensils. Estimates of total dietary exposure should reflect frequency distribution data on lead levels in specific food commodities in relation to the quantities actually ingested by various sample populations to distinguish degrees of risk associated with particular dietary habits. Earlier estimates of average total dietary intake of lead by adults have been reported to range from above 500 μg/day downward with more recent estimates suggesting averages of 200 μg/day or lower. The strengths and weaknesses of these data are discussed along with analytical and sampling considerations. FDA programs related to food surveillance, epidemiology, and toxicological investigation are briefly described. PMID:4406646

  3. Exposure to Amphetamines Leads to Development of Amphetamine Type Stimulants Associated Cardiomyopathy (ATSAC).

    PubMed

    Jafari Giv, Mahsa

    2017-01-01

    With rapidly rising prevalence of exposure to Amphetamine Type Stimulants (ATS), novel insights into cardiotoxic effects of this substance are being presented in the literature and remarkably ATS Associated Cardiomyopathy (ATSAC) is emerging as a novel cardiovascular condition with its distinctive pathogenesis, risk factors, clinical features and prognosis. A comprehensive systematic review was performed to explore and analyze the current evidence on the association between ATS exposure and development of cardiomyopathy, biological mechanisms involved in pathogenesis of ATSAC, risk factors, clinical features and course of patients with ATSAC. Several animal studies, case reports, case series and case-control studies support the association between ATS exposure and ATSAC. Oxidative stress, accelerated apoptosis, increased p53 activity, cardiomyocyte necrosis, perfusion defects, fatty acid toxicity, altered gene expression, abnormal cardiac protein synthesis and function in addition to defects in intracellular calcium hemostasis present themselves as likely mechanisms of cardiotoxicity in ATSAC. Majority of patients with ATSAC were found to be male, young and presented late with severe dilated cardiomyopathy. Female ATS users predominantly develop Takotsubo type of ATSAC and in particular its atypical basal variant. Overall, cessation of ATS exposure seems to be associated with some degree of reversibility and recovery in ATSAC sufferers.

  4. DETERMINANTS OF RESIDENTIAL LEAD EXPOSURE

    EPA Science Inventory

    The phase-out of leaded gasoline, and the accompanying decrease in lead emissions, resulted in a dramatic decline in mean blood lead levels from the late 1970s through the early 1990s. Nonetheless, lead exposures remain a public health concern. Long-term exposures to even low...

  5. DETERMINANTS OF RESIDENTIAL LEAD EXPOSURE

    EPA Science Inventory

    The phase-out of leaded gasoline, and the accompanying decrease in lead emissions, resulted in a dramatic decline in mean blood lead levels from the late 1970s through the early 1990s. Nonetheless, lead exposures remain a public health concern. Long-term exposures to even low...

  6. Neurohumoral blood pressure regulation in lead exposure

    SciTech Connect

    Boscolo, P.; Carmignani, M.

    1988-06-01

    Previous human studies demonstrated that lead exposure may modify the metabolism of catecholamines and of hormones controlled by the hypothalamo-pituitary axis and may affect the kallikrein-kinin system. This paper reports unpublished data on the plasma renin activity of lead-exposed workers; these results are in agreement with those of previous human and experimental studies suggesting that the synthesis or release of renin is increased after short and moderate exposure to inorganic lead and reduced whenever the exposure is prolonged. Previous experimental investigations demonstrated that lead may act on the cardiovascular system, with effects on the renin-angiotensin system, on the reactivity to stimulation of peripheral catecholaminergic receptors, on sympathetic and vagal tone, and on reactivity to the stimulation of baroreceptors. This paper reports the results of a study on male Sprague-Dawley rats that received 0, 15, 30, and 60 ..mu..g/mL of lead in drinking water for 18 months. Blood pressure was increased in the rats receiving 30 and 60 ppm of lead; cardiac inotropism was augmented only in those receiving the higher dose of the metal, and heart rate was not modified. Cardiovascular responses to agonists indicated that lead exposure affects the renin-angiotensin system and induces sympathetic hyperactivity be acting on central and peripheral sympathetic junctions increasing the responsiveness to stimulation of ..cap alpha../sub 2/-adrenoreceptors and by increasing the reactivity to stimulation of cardiac and vascular ..beta..-adrenergic and dopaminergic receptors.

  7. Lead Aprons Are a Lead Exposure Hazard.

    PubMed

    Burns, Kevin M; Shoag, Jamie M; Kahlon, Sukhraj S; Parsons, Patrick J; Bijur, Polly E; Taragin, Benjamin H; Markowitz, Morri

    2017-05-01

    To determine whether lead-containing shields have lead dust on the external surface. Institutional review board approval was obtained for this descriptive study of a convenience sample of 172 shields. Each shield was tested for external lead dust via a qualitative rapid on-site test and a laboratory-based quantitative dust wipe analysis, flame atomic absorption spectrometry (FAAS). The χ(2) test was used to test the association with age, type of shield, lead sheet thickness, storage method, and visual and radiographic appearance. Sixty-three percent (95% confidence interval [CI]: 56%-70%) of the shields had detectable surface lead by FAAS and 50% (95% CI: 43%-57%) by the qualitative method. Lead dust by FAAS ranged from undetectable to 998 μg/ft(2). The quantitative detection of lead was significantly associated with the following: (1) visual appearance of the shield (1 = best, 3 = worst): 88% of shields that scored 3 had detectable dust lead; (2) type of shield: a greater proportion of the pediatric patient, full-body, and thyroid shields were positive than vests and skirts; (3) use of a hanger for storage: 27% of shields on a hanger were positive versus 67% not on hangers. Radiographic determination of shield intactness, thickness of interior lead sheets, and age of shield were unrelated to presence of surface dust lead. Sixty-three percent of shields had detectable surface lead that was associated with visual appearance, type of shield, and storage method. Lead-containing shields are a newly identified, potentially widespread source of lead exposure in the health industry. Copyright © 2016 American College of Radiology. Published by Elsevier Inc. All rights reserved.

  8. Neurohumoral blood pressure regulation in lead exposure.

    PubMed Central

    Boscolo, P; Carmignani, M

    1988-01-01

    Previous human studies demonstrated that lead exposure may modify the metabolism of catecholamines and of hormones controlled by the hypothalamo-pituitary axis and may affect the kallikrein-kinin system. This paper reports unpublished data on the plasma renin activity of lead-exposed workers; these results are in agreement with those of previous human and experimental studies suggesting that the synthesis or release of renin is increased after short and moderate exposure to inorganic lead and reduced whenever the exposure is prolonged. Previous experimental investigations demonstrated that lead may act on the cardiovascular system, with effects on the renin-angiotensin system, on the reactivity to stimulation of peripheral catecholaminergic receptors, on sympathetic and vagal tone, and on reactivity to the stimulation of baroreceptors. This paper reports the results of a study on male Sprague-Dawley rats that received 0, 15, 30, and 60 micrograms/mL of lead in drinking water for 18 months. Blood pressure was increased in the rats receiving 30 and 60 ppm of lead; cardiac inotropism was augmented only in those receiving the higher dose of the metal, and heart rate was not modified. Cardiovascular responses to agonists indicated that lead exposure affects the renin-angiotensin system and induces sympathetic hyperactivity by acting on central and peripheral sympathetic junctions increasing the responsiveness to stimulation of alpha 2-adrenoreceptors and by increasing the reactivity to stimulation of cardiac and vascular beta-adrenergic and dopaminergic receptors. The cAMP-dependent availability of Ca2+ for contractile mechanisms of the cardiovascular muscle cells was affected by lead. PMID:3060351

  9. Reducing lead exposure in children

    SciTech Connect

    Farfel, M.R.

    1985-01-01

    The near elimination of lead-related childhood fatalities and encephalopathy by the 1970s and the sharp decline in mean blood lead levels nationwide documented between 1976 and 1980 are two milestones in the fight against lead poisoning. In the case of the latter, we know the antecedents, such as controls on the sale, use, and lead content of lead paint, improved chelation therapy, and increased awareness and case finding; however, the antecedents' relative contributions are not known due to a lack of evaluation. Similarly, the effect of a variety of social-welfare programs has not been evaluated. Since the 1970s, our perception of the problem of lead toxicity and consequently its control has changed. First steps have been made toward attaining one primary preventive objective, controlling the multiple sources of new inputs of lead to the biosphere that contribute to asymptomatic lead toxicity. The lead content of widely used commodities has been reduced (canned foods and gasoline) or virtually eliminated (paint). The benefits of passive measures used to attain reductions in lead exposure have been documented to a greater extent than those of active programs. The best example of a successful primary and passive preventive measure is the availability of lead-free gasoline since 1974, which largely accounts for decreases in ambient air lead concentrations nationwide and the recent shift to lower values in the distribution curve of children's blood lead levels. The latter provides a margin of safety for children before known toxic levels are reached. The contribution of reductions in dietary lead to changes in blood lead levels has not been well documented. Studies also show the benefits of the use of lead-free paint in new housing. Compared to children living in older homes with deteriorating lead paint, those living in lead-free homes are at low risk for lead toxicity.

  10. DNA methylation changes in whole blood is associated with exposure to the environmental contaminants, mercury, lead, cadmium and bisphenol A, in women undergoing ovarian stimulation for IVF.

    PubMed

    Hanna, Courtney W; Bloom, Michael S; Robinson, Wendy P; Kim, Dongsul; Parsons, Patrick J; vom Saal, Frederick S; Taylor, Julia A; Steuerwald, Amy J; Fujimoto, Victor Y

    2012-05-01

    Changes in DNA methylation may play an important role in the deleterious reproductive effects reported in association with exposure to environmental pollutants. In this pilot study, we identify candidate methylation changes associated with exposure to pollutants in women undergoing in vitro fertilization (IVF). Blood and urine were collected from women on the day of oocyte retrieval. Whole blood was analyzed for mercury and lead, and urine for cadmium using inductively coupled plasma mass spectrometry. Unconjugated bisphenol A (BPA) was analyzed in serum using high-performance liquid chromatography with Coularray detection. Participants were dichotomized as higher or lower exposure groups by median concentrations. Using the Illumina GoldenGate Methylation Cancer Panel I, DNA methylation in whole blood from 43 women was assessed at 1505 CpG sites for association with exposure levels of each pollutant. Candidate CpG sites were identified using a Diff Score >|13| (P< 0.05) and an absolute difference >10% which were confirmed using bisulfite pyrosequencing. Methylation of the GSTM1/5 promoter was increased for women with higher mercury exposure (P= 0.04); however, no correlation was observed (r= 0.17, P= 0.27). Reduced methylation was detected in the COL1A2 promoter in women with higher exposure to lead (P= 0.004), and an inverse correlation was observed (r = - 0.45, P= 0.03). Lower methylation of a promoter CpG site at the TSP50 gene was detected in women with higher BPA exposure (P= 0.005), and again an inverse correlation was identified (r = - 0.51, P= 0.001). Altered DNA methylation at various CpG sites was associated with exposure to mercury, lead or BPA, providing candidates to be investigated using a larger study sample, as the results may reflect an independently associated predictor (e.g. socioeconomic status, diet, genetic variants, altered blood cell composition). Further studies accommodating variations in these factors will be needed to confirm these

  11. Effects of occupational lead exposure.

    PubMed

    Wang, Y L; Lu, P K; Chen, Z Q; Liang, Y X; Lu, Q M; Pan, Z Q; Shao, M

    1985-01-01

    Fifty-three workers in a battery factory, 52 solderers in a television factory, and 50 embroidery workers (a reference group) were studied. The average air lead levels of the three workplaces were 0.578 mg/m3, 0.002 mg/m3, and 0.001 mg/m3, respectively. Adverse effects in terms of clinical manifestations and biochemical criteria were evident among the battery factory workers. A significant dose-response relationship existed between the toxic effects and the air lead levels. The solderers showed no apparent abnormalities in comparison with the embroidery workers. The early clinical manifestations were dysfunction of the central nervous system, indigestion, arthralgia, and myalgia in the extremities. A positive association was observed between the prevalence of fatigue, mild abdominal pain, and arthralgia and the blood lead (PbB), urinary lead (PbU), and zinc protoporphyrin (ZPP) levels. The symptomatic threshold values of PbB, PbU, and ZPP were 30 micrograms/dl (1.5 mumol/l), 0.045 mg/l (0.2 mumol/l), and 40 micrograms/dl (0.7 mumol/l), respectively. The PbB, PbU, free erythrocyte protoporphyrin, and ZPP levels and the blood aminolevulinic dehydratase ratio could be used as indicators of lead exposure, although ZPP is preferred for a preventive monitoring program. The motor and sensory conduction velocities of the median nerve were slower in the exposed groups than in the reference group. No effects on behavioral function were observed among the solderers.

  12. Lead exposure in a firing range.

    PubMed Central

    Novotny, T; Cook, M; Hughes, J; Lee, S A

    1987-01-01

    We report lead exposure in four employees of a privately owned shooting range, one of whom had neurological toxicity due to lead. Increasing time worked at the range was associated with elevation of blood lead. This incident emphasizes the risk of airborne lead exposure to employees of firing ranges. PMID:3618861

  13. Developmental Effects of Lead Exposure in Children.

    ERIC Educational Resources Information Center

    Tesman, Johanna Rich; Hills, Amanda

    1994-01-01

    This report presents an overview of research on childhood lead exposure and poisoning, and the related social issues. The report first summarizes the history of lead poisoning and its prevalence in the United States, and discusses the basis for recent changes in guidelines for lead exposure by the Centers for Disease Control (CDC). The report then…

  14. Vestibular stimulation leads to distinct hemodynamic patterning

    NASA Technical Reports Server (NTRS)

    Kerman, I. A.; Emanuel, B. A.; Yates, B. J.

    2000-01-01

    Previous studies demonstrated that responses of a particular sympathetic nerve to vestibular stimulation depend on the type of tissue the nerve innervates as well as its anatomic location. In the present study, we sought to determine whether such precise patterning of vestibulosympathetic reflexes could lead to specific hemodynamic alterations in response to vestibular afferent activation. We simultaneously measured changes in systemic blood pressure and blood flow (with the use of Doppler flowmetry) to the hindlimb (femoral artery), forelimb (brachial artery), and kidney (renal artery) in chloralose-urethane-anesthetized, baroreceptor-denervated cats. Electrical vestibular stimulation led to depressor responses, 8 +/- 2 mmHg (mean +/- SE) in magnitude, that were accompanied by decreases in femoral vasoconstriction (23 +/- 4% decrease in vascular resistance or 36 +/- 7% increase in vascular conductance) and increases in brachial vascular tone (resistance increase of 10 +/- 6% and conductance decrease of 11 +/- 4%). Relatively small changes (<5%) in renal vascular tone were observed. In contrast, electrical stimulation of muscle and cutaneous afferents produced pressor responses (20 +/- 6 mmHg) that were accompanied by vasoconstriction in all three beds. These data suggest that vestibular inputs lead to a complex pattern of cardiovascular changes that is distinct from that which occurs in response to activation of other types of somatic afferents.

  15. Time To Pregnancy and occupational lead exposure

    PubMed Central

    Joffe, M; Bisanti, L; Apostoli, P; Kiss, P; Dale, A; Roeleveld, N; Lindbohm, M; Sallmen, M; Vanhoorne, M; Bonde, J

    2003-01-01

    Background: Lead exposure is known to be harmful to the male reproductive system, including impairment of fertility. However, it is unclear whether currently existing low levels of exposure have this effect. Aims: To study retrospectively current workers in lead using industries (battery manufacture, smelting, etc), and in non-lead using control industries, in four European countries, with Time To Pregnancy as the outcome variable, as part of the EU funded Asclepios Project. Methods: Exposure assessment was mainly by blood lead values, which were available from the late 1970s, supplemented by imputed values where necessary. Three exposure models were studied: (1) short term (recent) exposure; (2) total duration of work in a lead using industry; and (3) cumulative exposure. A Cox proportional hazards model with discrete ties was used for the statistical analysis, with covariates for both partners. Results: A total of 1104 subjects took part, of whom 638 were occupationally exposed to lead at the relevant time. Blood lead levels were mainly less than 50 µg/dl. No consistent association of Time To Pregnancy with lead exposure was found in any of the exposure models, although reduced fertility was observed in one category each in models (2) and (3). Conclusions: This basically negative result is unlikely to be due to the misclassification of key variables, to insufficient statistical power, or to bias, for example, response bias. If any impairment of male reproductive function exists at the levels of occupational lead exposure now current, it does not appear to reduce biological fertility. PMID:14504363

  16. Time To Pregnancy and occupational lead exposure.

    PubMed

    Joffe, M; Bisanti, L; Apostoli, P; Kiss, P; Dale, A; Roeleveld, N; Lindbohm, M-L; Sallmén, M; Vanhoorne, M; Bonde, J P

    2003-10-01

    Lead exposure is known to be harmful to the male reproductive system, including impairment of fertility. However, it is unclear whether currently existing low levels of exposure have this effect. To study retrospectively current workers in lead using industries (battery manufacture, smelting, etc), and in non-lead using control industries, in four European countries, with Time To Pregnancy as the outcome variable, as part of the EU funded Asclepios Project. Exposure assessment was mainly by blood lead values, which were available from the late 1970s, supplemented by imputed values where necessary. Three exposure models were studied: (1) short term (recent) exposure; (2) total duration of work in a lead using industry; and (3) cumulative exposure. A Cox proportional hazards model with discrete ties was used for the statistical analysis, with covariates for both partners. A total of 1104 subjects took part, of whom 638 were occupationally exposed to lead at the relevant time. Blood lead levels were mainly less than 50 microg/dl. No consistent association of Time To Pregnancy with lead exposure was found in any of the exposure models, although reduced fertility was observed in one category each in models (2) and (3). This basically negative result is unlikely to be due to the misclassification of key variables, to insufficient statistical power, or to bias, for example, response bias. If any impairment of male reproductive function exists at the levels of occupational lead exposure now current, it does not appear to reduce biological fertility.

  17. Fetal lead exposure: antenatal factors

    SciTech Connect

    Ernhart, C.B.; Wolf, A.W.; Sokol, R.J.; Brittenham, G.M.; Erhard, P.

    1985-10-01

    It was hypothesized that maternal blood lead level at delivery and cord blood lead level of the neonate would be affected by maternal use of alcohol, history of alcohol abuse, and smoking. The possibility that iron status, as reflected in maternal serum ferritin, would be related to lead level was also explored. The maternal history of alcohol abuse was unrelated to lead level in 208 samples of maternal blood and 178 samples of cord blood. However, alcohol use during pregnancy was related in a dose-response fashion to maternal and to cord blood lead level. This effect was significant with and without control of maternal smoking. The effect of maternal smoking and serum thiocyanate on maternal and cord blood lead level were also highly significant with and without control of the maternal drinking variable. Serum ferritin was marginally related to lead level for white women and for black infants, but tests of the dichotomized maternal ferritin variable did not yield a significant linkage with maternal or cord blood lead level. The results further support recommendations that women abstain from alcohol consumption and cigarette smoking in pregnancy.

  18. Lead Exposure Hazard Management Guide

    DTIC Science & Technology

    1993-12-01

    one of the most common and preventable pediatric health problems in the United States today. Children are particularly susceptible to lead’s toxic...that have large percentages of children without lead poisoning problems can suspend the universal screening PROGRAM by submitting a letter of request, to...be frequented/used by children under the age of seven. Air Force Policy prioritizes specific facilities as follows: child development centers, annexes

  19. Relationship between prenatal lead exposure and infant blood lead levels.

    PubMed

    Archer, Natalie P; Bradford, Carrie M; Klein, David M; Barnes, Jim; Smith, L J; Villanacci, John F

    2012-10-01

    Recent literature has shown that analyzing newborn dried blood spots (DBS) may be effective in assessing some prenatal environmental exposures, such as exposure to lead. The purpose of this study was to evaluate the relationship between prenatal exposure to lead (as measured by newborn DBS results) and blood lead levels (BLLs) in infants 6 months of age or younger, using public health registry data for infants born in Texas from July 2002 through July 2006. The Texas Child Lead Registry (TCLR) was used to identify infants with documented elevated BLLs of 10 μg/dL or higher as well as infants with documented low BLLs. BLLs for these children were compared to their corresponding newborn DBS results using Pearson correlation coefficients and exact logistic regression models. Overall, a significant but weak positive correlation was found between infant BLLs and corresponding newborn DBS lead levels (r = 0.48). However, the odds of an infant with an elevated newborn DBS lead level having an elevated BLL at 6 months of age or younger were much greater than for an infant with a low newborn DBS lead level of <5 μg/dL (adjusted odds ratio 27.95, 95% CI: 5.52-277.28). Although an association was observed between newborn DBS lead levels and BLLs in infants tested between 0 to 6 months of age, our findings suggest that prenatal exposure may not be the only significant source of lead exposure for infants ≤6 months of age.

  20. Psychiatric epidemiologic study of occupational lead exposure

    SciTech Connect

    Parkinson, D.K.; Ryan, C.; Bromet, E.J.; Connell, M.M.

    1986-02-01

    The association of occupational lead exposure with neuropsychiatric functioning was evaluated using data collected in 1982 in eastern Pennsylvania from 288 lead-exposed workers and 181 nonexposed subjects. Both current and cumulative exposure indices were used. After controlling for age, education, and income, few meaningful differences between exposed and control workers were found on either neuropsychologic or psychosocial variables. Dose-response analyses indicated that among lead-exposed workers, cumulative and current exposure were unrelated to neuropsychologic performance. The only meaningful associations occurred between exposure and level of conflict in interpersonal relationships. The results thus give evidence against hypotheses suggesting adverse neuropsychologic effects.

  1. Environmental lead exposure and the kidney

    SciTech Connect

    Bernard, B.P.; Becker, C.E.

    1988-01-01

    Lead and its components remain widely distributed in the environment and in some workplaces. Lead serves no useful physiological function, yet is potentially toxic to several organ systems. For many years human health effects have been recognized after heavy lead exposure. Recently more subtle human effects have been suggested invoking nervous system, reproductive and kidney function. Assessing lead body burden and dose-response relationships of this metal by blood lead determination, porphyrin assessments, chelation testing or bone lead studies may be difficult. Quantitative assessment of subtle changes in kidney function by routine BUN, creatinine, or urinalysis also poses problems. There is now mounting evidence that chronic low level environmental lead exposure may subtly effect kidney function. This paper first examines the history of lead and kidney function and then examines critically the evidence associating low-level environmental lead exposure and effects on renal function. 119 references.

  2. Lead absorption in cows: biological indicators of ambient lead exposure

    SciTech Connect

    Karacic, V.; Prpic-Majic, D.; Skender, L.

    1984-03-01

    In order to determine actual lead exposure from residual amounts of lead in the environmental soil following the introduction of effective engineering emission controls in a lead smeltery, the absorption of lead in cows grazing in the vicinity was investigated. Four groups of cows were examined: two groups of cows exposed to different ambient lead concentration, compared with two normal groups of cows. In each cow aminolevulinic acid dehydratase (ALAD), erythrocyte protoporphyrin (EP) and blood lead (Pb-B) were determined, two years prior to and four years after the technical sanitation of the lead emission source. The results demonstrated normalization of ALAD, EP and Pb-B after the technical sanitation. In spite of normalization, biological indicators ALAD and Pb-B determined four years after the technical sanitation showed increased lead absorption in comparison with the results of the control group. This indirectly indicates lead contamination of the environment from residual amounts of lead in the soil.

  3. Overview of radon, lead and asbestos exposure

    SciTech Connect

    Demers, R. )

    1991-11-01

    Reducing the incidence of diseases caused by exposure to radon, lead and asbestos is a major public health challenge. Radon gas, which usually enters a home through the foundation, can cause lung cancer. Exposure to lead through paint, auto emissions and other sources can cause neurologic deficits, as well as anemia, abnormal vitamin D metabolism, nephropathy, hypertension and reproductive abnormalities. Asbestos, which is used in a vast number of products, is primarily associated with parenchymal asbestosis, pleural fibrosis, mesothelioma and lung cancer. The family physician can play a pivotal role in providing information about hazardous exposure, sources of exposure, epidemiology and disease prevention.29 references.

  4. DIETARY EXPOSURE OF CHILDREN TO LEAD

    EPA Science Inventory

    Children are the most susceptible population to lead exposure because 1) they have more opportunity for contact with lead sources due to their activities, 2) lead adsorption occurs more readily in a child as compared to an adult, and 3) the child's development is more vulnerable ...

  5. DIETARY EXPOSURE OF CHILDREN TO LEAD

    EPA Science Inventory

    Children are the most susceptible population to lead exposure because 1) they have more opportunity for contact with lead sources due to their activities, 2) lead adsorption occurs more readily in a child as compared to an adult, and 3) the child's development is more vulnerable ...

  6. High lead exposure in two leaded bronze ingot foundry workers.

    PubMed

    Song, Yoojun; Suh, Chunhui; Kim, Shin-Ae; Kim, Nami; Kim, Sung-Min; Jeong, Seong-Wook; Kim, Se-Yeong; Kim, Kun-Hyung; Kim, Jeong-Ho; Son, Byung-Chul; Lee, Chae-Kwan; Lee, Jong-Tae

    2014-01-01

    Awareness about lead poisoning in South Korea has increased; however, occupational exposures occurring in small-scale businesses have not been thoroughly investigated. We report two cases of high lead exposure in a leaded bronze ingot foundry. Two employees, a 54-year-old primary operator and a 46-year-old assistant, at a small-scale metalworking company who had been employed for 18 years and 1 month, respectively, showed elevated blood lead levels (61.1 μg/dL and 51.7 μg/dL, respectively) at an occupational health checkup. Neither worker complained of abnormal symptoms nor signs related to lead poisoning. Health assessment follow-ups were conducted and biological exposure indices of lead were calculated every four weeks. After the initial follow-up assessment, both workers were relocated from the foundry process to the metalworking process. In addition, a localized exhaust system was installed after the second follow-up. Foundry workers in a small-scale businesses might be at high risk of lead exposure because these businesses might be vulnerable to poor industrial hygiene. Therefore, regular occupational health checkups are required.

  7. Blood pressure and industrial lead exposure.

    PubMed

    Maheswaran, R; Gill, J S; Beevers, D G

    1993-03-15

    The association between environmental lead exposure and raised blood pressure remains controversial. This association was examined in a cross-sectional study in 1981 on 809 male workers who were occupationally exposed to lead in a factory manufacturing car lead accumulator batteries in Birmingham, United Kingdom. Lead exposure was assessed by blood lead levels, blood zinc protoporphyrin levels, and years of industrial exposure to lead. The geometric mean blood lead level was 31.6 micrograms/dl with minimum and maximum values of 0 microgram/dl and 98 micrograms/dl, respectively. Unadjusted systolic blood pressure rose with increasing blood lead levels (analysis of variance, F = 3.3, p < 0.05) from 127 mmHg (95% confidence interval (CI) 123.5-130.5) in men with blood lead levels less than 21 micrograms/dl to 133 mmHg (95% CI 128.7-137.3) in men with levels exceeding 50 micrograms/dl. Following adjustment for the confounding effects of age, body mass index, and alcohol consumption, however, the effect of blood lead on systolic pressure was diminished (analysis of variance, F = 1.3, not significant) to 129 mmHg and 132 mmHg in the respective categories. There was no association between diastolic blood pressure and blood lead. Zinc protoporphyrin levels and years of industrial lead exposure did not raise adjusted systolic or diastolic pressure. In conclusion, subject to the limitations inherent in a cross-sectional survey, the findings are consistent with a weak effect of industrial lead exposure on systolic blood pressure, within the range of exposures observed in this study.

  8. Human biomonitoring issues related to lead exposure.

    PubMed

    Nieboer, Evert; Tsuji, Leonard J S; Martin, Ian D; Liberda, Eric N

    2013-10-01

    Lead as a toxic environmental metal has been an issue of concern for 30-40 years. Even though the exposures experienced by the general public have been significantly reduced, so have the acceptable blood lead concentrations assessed to safeguard health (specifically of children). The impact of these concurrent changes are reviewed and discussed in terms of the following: blood lead as the primary biomarker of exposure; pertinent toxicokinetic issues including modelling; legacy and newer sources of this toxic metal; improvements in lead quantification techniques and its characterization (chemical forms) in exposure media; and in vivo markers of lead sources. It is concluded that the progress in the quantification of lead and its characterization in exposure media have supported the efforts to identify statistical associations of lead in blood and tissues with adverse health outcomes, and have guided strategies to reduce human exposure (especially for children). To clarify the role of lead as a causative factor in disease, greater research efforts in biomarkers of effect and susceptibility seem timely.

  9. Occupational lead exposure and blood pressure.

    PubMed Central

    Parkinson, D K; Hodgson, M J; Bromet, E J; Dew, M A; Connell, M M

    1987-01-01

    Recent community studies have suggested that low level lead exposure is significantly associated with blood pressure in the general population. This finding is inconsistent with the results of recent occupational studies of lead exposed workers, although the occupational studies contained serious methodological weaknesses. The present study examined the relation between occupational lead exposure and diastolic and systolic blood pressure in randomly selected samples of 270 exposed and 158 non-exposed workers. Four exposure indicators were examined: employment at a lead battery plant nu a control plant, current blood lead value, current zinc protoporphyrin value, and time weighted average blood lead value. After controlling for other known risk factors such as age, education, income, cigarette usage, alcohol consumption, and exercise, the associations between exposure and blood pressure were small and non-significant. In the absence of a biologically feasible hypothesis regarding the mechanism by which low level lead exposure would influence blood pressure the present findings challenge the validity of the general population association. PMID:3689706

  10. Lead exposure in outdoor firearm instructors

    SciTech Connect

    Tripathi, R.K.; Sherertz, P.C.; Llewellyn, G.C.; Armstrong, C.W. )

    1991-06-01

    This study was conducted to determine lead exposure of firearm instructors at an outdoor firing range, while cadets were firing nonjacketed and jacketed lead ammunitions. The breathing zone air for lead exceeded the Occupational Safety and Health Administration standard of 50 micrograms/m3 for two instructors during firing exercises using nonjacketed bullets. The use of totally copper-jacketed bullets reduced the breathing zone lead levels by 92 percent for instructor {number sign}1 and by 96 percent for instructor {number sign}2; subsequent blood lead levels showed a significant decline in both instructors.

  11. Sources of lead exposure in Mexico City.

    PubMed Central

    Romieu, I; Palazuelos, E; Hernandez Avila, M; Rios, C; Muñoz, I; Jimenez, C; Cahero, G

    1994-01-01

    Many countries, including Mexico, are facing a largely unrecognized epidemic of low-level lead poisoning. Mexico is the sixth largest lead-producing country in the world, and 40% of its production is used locally in different industrial processes that cause lead contamination of the environment. The major sources and pathways of lead exposure among the Mexican population are gasoline emissions, lead-glazed ceramics, leaded paint, and lead in canned foods and beverages. In this paper we present evidence for the presence of lead in different environmental media and its impact on blood lead levels of the Mexican population. Although during the last few years important measures have been implemented to decrease lead exposure, our findings suggest that lead poisoning is still an important problem in Mexico. There is an urgent need for regulatory policies that implement stricter control to protect the Mexican population. There is also a need to develop adequate programs to reduce the lead burden and the associated health effects in the population that has been chronically exposed. Images Figure 1. PMID:7523102

  12. Sources of lead exposure in Mexico City.

    PubMed

    Romieu, I; Palazuelos, E; Hernandez Avila, M; Rios, C; Muñoz, I; Jimenez, C; Cahero, G

    1994-04-01

    Many countries, including Mexico, are facing a largely unrecognized epidemic of low-level lead poisoning. Mexico is the sixth largest lead-producing country in the world, and 40% of its production is used locally in different industrial processes that cause lead contamination of the environment. The major sources and pathways of lead exposure among the Mexican population are gasoline emissions, lead-glazed ceramics, leaded paint, and lead in canned foods and beverages. In this paper we present evidence for the presence of lead in different environmental media and its impact on blood lead levels of the Mexican population. Although during the last few years important measures have been implemented to decrease lead exposure, our findings suggest that lead poisoning is still an important problem in Mexico. There is an urgent need for regulatory policies that implement stricter control to protect the Mexican population. There is also a need to develop adequate programs to reduce the lead burden and the associated health effects in the population that has been chronically exposed.

  13. Lead exposure among lead-acid battery workers in Jamaica.

    PubMed

    Matte, T D; Figueroa, J P; Burr, G; Flesch, J P; Keenlyside, R A; Baker, E L

    1989-01-01

    To assess lead exposure in the Jamaican lead-acid battery industry, we surveyed three battery manufacturers (including 46 production workers) and 10 battery repair shops (including 23 battery repair workers). Engineering controls and respiratory protection were judged to be inadequate at battery manufacturers and battery repair shops. At manufacturers, 38 of 42 air samples for lead exceeded a work-shift time-weighted average concentration of 0.050 mg/m3 (range 0.030-5.3 mg/m3), and nine samples exceeded 0.50 mg/m3. Only one of seven air samples at repair shops exceeded 0.050 mg/m3 (range 0.003-0.066 mg/m3). Repair shop workers, however, had higher blood lead levels than manufacturing workers (65% vs. 28% with blood lead levels above 60 micrograms/dl, respectively). Manufacturing workers had a higher prevalence of safe hygienic practices and a recent interval of minimal production had occurred at one of the battery manufacturers. Workers with blood lead levels above 60 micrograms/dl tended to have higher prevalences of most symptoms of lead toxicity than did workers with lower blood lead levels, but this finding was not consistent or statistically significant. The relationship between zinc protoporphyrin concentrations and increasing blood lead concentrations was consistent with that described among workers in developed countries. The high risk of lead toxicity among Jamaican battery workers is consistent with studies of battery workers in other developing countries.

  14. [Children exposure to lead in contaminated sites].

    PubMed

    Flores-Ramírez, Rogelio; Rico-Escobar, Edna; Núñez-Monreal, Jorge E; García-Nieto, Edelmira; Carrizales, Leticia; Ilizaliturri-Hernández, César; Díaz-Barriga, Fernando

    2012-01-01

    To assess the exposure to lead in children living in various types of contaminated sites. The study was conducted from June 2008 to December 2009 at four sites in Mexico: Avalos metallurgical, Chihuahua; Morales metallurgical, San Luis Potosí (SLP); Trinidad pottery area, Tlaxcala and Cedral mine site, SLP. These sites contain different sources of lead. The metal levels were quantified in outdoor dust and in peripheral blood of children. Lead dust concentrations exceed the National Guidelines for residential soils (400 mg/kg) in a range of values for the four sites from 62 to 5 187 mg/kg. Regarding biological monitoring, the studied children showed maximum lead blood levels of 22 µg/dL in Cedral, 31 µg/dL in Morales, 32 µg/dL in Avalos, and 52 µg/dL in Trinidad. It is important to mention that in all the studied sites, a significative positive correlation was found between blood lead levels and the lead concentrations in dust. These sites are an example of the health risks related to lead exposure in Mexico; therefore, there is an urgent need for a national public health program aimed at reducing lead exposure in vulnerable populations.

  15. Human lead exposure: Some recent research findings

    SciTech Connect

    Saryan, L.A.

    1999-09-01

    One of the practical problems facing industrial hygienists and safety managers in the lead industry is finding new ways to limit or reduce lead intake in order to protect workers from the deleterious effects of this metal. Exposure to lead generally takes place by inhalation of airborne particles and by ingestion. Airborne exposure is comparatively well understood and methods for the control of airborne lead have been developed and put into place in industrial facilities. Both for the general public and for workers, however, it is thought that a significant fraction of the total lead intake occurs by ingestion as opposed to inhalation. Furthermore, factors such as personal hygiene, hand washing, diet, cigarette smoking, alcohol consumption, use of medications, bone injury, existing disease, and others may also have positive or negative effects on lead absorption and blood lead levels. How these variables actually operate in practice for lead-exposed workers is unfortunately not very well understood. As scientific and medical knowledge increases, progress has been made in the understanding of some of the factors affecting blood lead levels. In this article, the author summarizes the findings of a few interesting recent reports that point the way toward future progress in this area.

  16. Neural alterations from lead exposure in zebrafish.

    PubMed

    Roy, Nicole M; DeWolf, Sarah; Schutt, Alexius; Wright, Ashia; Steele, Latina

    2014-01-01

    Lead was used extensively as a gas additive and pesticide, in paints, batteries, lead shot, pipes, canning and toy manufacturing. Although uses of lead have been restricted, lead persists in our environment especially in older homes, and generally in soil and water. Although extensive studies have determined that fetal and childhood exposures to lead have been associated with childhood and adolescent memory impairments and learning disabilities, there are limited studies investigating early neural and morphological effects that may lead to these behavioral and learning abnormalities. Here we utilize the zebrafish vertebrate model system to study early effects of lead exposure on the brain. We treat embryos with 0.2mM lead for 24, 48 and 72 h and analyze neural structures through live imagery and transgenic approaches. We find structural abnormalities in the hindbrain region as well as changes in branchiomotor neuron development and altered neural vasculature. Additionally, we find areas of increased apoptosis. We conclude that lead is developmentally neurotoxic to a specific region of the brain, the hindbrain and is toxic to branchiomotor neurons residing in rhombomeres 2 through 7 of the hindbrain and hindbrain central artery vasculature.

  17. Lead exposure from aluminum cookware in Cameroon.

    PubMed

    Weidenhamer, Jeffrey D; Kobunski, Peter A; Kuepouo, Gilbert; Corbin, Rebecca W; Gottesfeld, Perry

    2014-10-15

    Blood lead levels have decreased following the removal of lead from gasoline in most of the world. However, numerous recent studies provide evidence that elevated blood lead levels persist in many low and middle-income countries around the world at much higher prevalence than in the more developed countries. One potential source of lead exposure that has not been widely investigated is the leaching of lead from artisanal aluminum cookware, which is commonly used in the developing world. Twenty-nine samples of aluminum cookware and utensils manufactured by local artisans in Cameroon were collected and analyzed for their potential to release lead during cooking. Source materials for this cookware included scrap metal such as engine parts, radiators, cans, and construction materials. The lead content of this cookware is relatively low (<1000 ppm by X-ray fluorescence), however significant amounts of lead, as well as aluminum and cadmium were released from many of the samples using dilute acetic acid extractions at boiling and ambient temperatures. Potential exposures to lead per serving were estimated to be as high as 260 μg, indicating that such cookware can pose a serious health hazard. We conclude that lead, aluminum and cadmium can migrate from this aluminum cookware during cooking and enter food at levels exceeding recommended public health guidelines. Our results support the need to regulate lead content of materials used to manufacture these pots. Artisanal aluminum cookware may be a major contributor to lead poisoning throughout the developing world. Testing of aluminum cookware in other developing countries is warranted.

  18. [Lead exposure among Kaohsiung traffic policemen].

    PubMed

    Chiang, H C; Chang, P Y

    1989-06-01

    In this recent century there has been increasing concern over the possible harmful effects of lead from automobile exhaust on human health. Traffic policemen are heavily exposed to automobile exhaust. In Kaohsiung city because of the increasing number of motor vehicles due to rapid urbanization and heavy traffic transportation from suburbs for export trade, traffic policemen have varied exposure experiences. The automobile exhaust of lead additive gasoline was found to be the major type of exposure for traffic policemen whose duties were in the city, while those who worked in the suburb areas were generally exposed to diesel oil exhaust gas. In this study 98 traffic policemen were studied with 118 students used as a control group. Subjects were evaluated for lead absorption and other metabolic effects. The average value of blood lead for traffic policemen (24.43 +/- 5.31 micrograms/dl) in the city of Kaohsiung was significantly (p less than 0.01) higher than for the control group (20.14 +/- 5.07 micrograms/dl). According to other bioindicators it was also found that the mean values of carboxyhemoglobin, urine lead and urine coproporphyrin were significantly higher in the traffic policemen group. Linear regression between blood lead and the duration of employment was also found in this study (R = -0.2447, p less than 0.05). The most reasonable explanations for these findings are the effects of lead emission from motor vehicles and the employment shifting system that cause this effect.

  19. Lead exposure and radiator repair work

    SciTech Connect

    Lussenhop, D.H.; Parker, D.L.; Barklind, A.; McJilton, C. )

    1989-11-01

    In 1986, the ambient air for lead in radiator repair shops in the Minneapolis-St. Paul metropolitan area exceeded the Occupational Safety and Health Administration (OSHA) action level in nine of 12 shops sampled by Minnesota OSHA. We therefore sought to determine the prevalence of lead exposure/toxicity in this industry. Thirty-five radiator shops were identified, 30 were visited, and 53 workers were studied. The mean blood lead level was 1.53 (range 0.24-2.80). Seventeen individuals had blood lead levels greater than or equal to 1.93 mumol/L (40 micrograms/dl). The mean zinc protoporphyrin level (ZPP) was 0.55 mumol/L (range 0.16-1.43). No single worksite or personal characteristic was a strong determinant of either blood lead or ZPP level.

  20. Lead exposure and radiator repair work.

    PubMed Central

    Lussenhop, D H; Parker, D L; Barklind, A; McJilton, C

    1989-01-01

    In 1986, the ambient air for lead in radiator repair shops in the Minneapolis-St. Paul metropolitan area exceeded the Occupational Safety and Health Administration (OSHA) action level in nine of 12 shops sampled by Minnesota OSHA. We therefore sought to determine the prevalence of lead exposure/toxicity in this industry. Thirty-five radiator shops were identified, 30 were visited, and 53 workers were studied. The mean blood lead level was 1.53 (range 0.24-2.80). Seventeen individuals had blood lead levels greater than or equal to 1.93 mumol/L (40 micrograms/dl). The mean zinc protoporphyrin level (ZPP) was 0.55 mumol/L (range 0.16-1.43). No single worksite or personal characteristic was a strong determinant of either blood lead or ZPP level. PMID:2817174

  1. Lead exposure and radiator repair work.

    PubMed

    Lussenhop, D H; Parker, D L; Barklind, A; McJilton, C

    1989-11-01

    In 1986, the ambient air for lead in radiator repair shops in the Minneapolis-St. Paul metropolitan area exceeded the Occupational Safety and Health Administration (OSHA) action level in nine of 12 shops sampled by Minnesota OSHA. We therefore sought to determine the prevalence of lead exposure/toxicity in this industry. Thirty-five radiator shops were identified, 30 were visited, and 53 workers were studied. The mean blood lead level was 1.53 (range 0.24-2.80). Seventeen individuals had blood lead levels greater than or equal to 1.93 mumol/L (40 micrograms/dl). The mean zinc protoporphyrin level (ZPP) was 0.55 mumol/L (range 0.16-1.43). No single worksite or personal characteristic was a strong determinant of either blood lead or ZPP level.

  2. Lead exposure in Mexican radiator repair workers.

    PubMed

    Dykeman, Ronald; Aguilar-Madrid, Guadalupe; Smith, Tom; Juárez-Pérez, Cuauhtemoc Arturo; Piacitelli, Gregory M; Hu, Howard; Hernandez-Avila, Mauricio

    2002-03-01

    Lead exposure was investigated among 73 Mexican radiator repair workers (RRWs), 12 members of their family (4 children and 8 wives), and 36 working controls. RRWs were employed at 4 radiator repair shops in Mexico City and 27 shops in Cuernavaca and surrounding areas. Exposure was assessed directly through the use of personal air sampling and hand wipe samples. In addition, industrial hygiene inspections were performed and detailed questionnaires were administered. Blood lead levels were measured by graphite furnace atomic absorption spectroscopy (AAS). The mean (SD) values for blood lead of the RRWs, 35.5 (13.5) microg/dl, was significantly greater than the same values for the working controls, 13.6 (8.7) microg/dl; P < 001. After excluding a single outlier (247 microg/m(3)), air lead levels ranged from 0 to 99 microg/m(3) with a mean (SD) value of 19 (23) microg/m(3) (median = 7.9 microg/m(3)). In a final multivariate regression model of elevated blood lead levels, the strongest predictors were smoking (vs. non-smoking), the number of radiators repaired per day on average, and the use (vs. non-use) of a uniform while at work, which were associated with blood lead elevations of 11.4 microg/dl, 1.95 microg/dl/radiator/day, and 16.4 microg/dl, respectively (all P <.05). Uniform use was probably a risk factor because they were not laundered regularly and consequently served as reservoir of contamination on which RRWs frequently wiped their hands. Lead exposure is a significant problem of radiator repair work, a small industry that is abundant in Mexico and other developing countries. Copyright 2002 Wiley-Liss, Inc.

  3. [Lead exposure of people living in a lead high exposure area from local diet].

    PubMed

    Zhou, Yong; He, Liping; Huang, Xiao; He, Junshan

    2011-11-01

    To study the lead exposure of people living in a lead high exposure area from local diet, and to assess its health risks. Thirty five subjects were selected by random from a mining area and another 30 subjects were selected from a non-polluted area. The exposure of lead was estimated by the content of lead in drinking water and vegetables, and health risks was estimated by the levels of lead in blood and urine. The content of lead in drinking water and vegetables in the mining area was 20.6 microg/L and 1.61mg/kg (geometric mean) respectively, which were higher than that in the unpolluted area (6.0 microg/L and 0.56 mg/kg, geometric mean) (P < 0.01). The daily lead exposure of male and female inhabitants in the mining area from diet was 16.88 microg/kg and 16.09 microg/kg respectively, which was higher than that in the unpolluted area (P < 0.01), but the sex difference was not significant statistically (P > 0.05). Blood lead and urine lead of inhabitants in the mining-area were higher than those in the unpolluted area. The health risks for male and female inhabitants in the mining area were 4.73 and 4.51. The health risks of lead exposure caused by diet (drinking water and food) were relatively high in the mining area.

  4. Exposure to lead exacerbates dental fluorosis.

    PubMed

    Leite, G A S; Sawan, R M M; Teófilo, J M; Porto, I M; Sousa, F B; Gerlach, R F

    2011-07-01

    Our aim was to test the hypothesis that co-exposure to lead and fluoride alter the severity of enamel fluorosis. Wistar rats were allocated in four groups: control, and 3 groups that received water containing 100 ppm of fluoride (F), 30 ppm of lead (Pb), or 100 ppm of F and 30 ppm of Pb (F+Pb) from the beginning of gestation. Enamel analysis and F and Pb determinations in enamel, dentine, and bone were performed in 81-day-old animals. Fluorosis was quantified using a new fluorosis index based on the identification of incisor enamel defects (white bands and white islets, representing hypomineralization, and cavities) weighted according to their severity and quantity. Hypomineralization was validated histopathologically by polarizing microscopy and microradiography. Scores were given by two blinded calibrated examiners (intra and interexaminer kappa values were 0.8 and 0.86, respectively). The control and the Pb groups presented normal enamel. The F+Pb group presented more severe enamel defects compared with the F group (P<0.0001). This study shows that lead exacerbates dental fluorosis in rodents, suggesting that co-exposure to lead may affect the degree of fluorosis. Copyright © 2011 Elsevier Ltd. All rights reserved.

  5. The Australian Work Exposures Study: Occupational Exposure to Lead and Lead Compounds.

    PubMed

    Driscoll, Timothy R; Carey, Renee N; Peters, Susan; Glass, Deborah C; Benke, Geza; Reid, Alison; Fritschi, Lin

    2016-01-01

    The aims of this study were to produce a population-based estimate of the prevalence of work-related exposure to lead and its compounds, to identify the main circumstances of exposures, and to collect information on the use of workplace control measures designed to decrease those exposures. Data came from the Australian Workplace Exposures Study, a nationwide telephone survey which investigated the current prevalence and circumstances of work-related exposure to 38 known or suspected carcinogens, including lead, among Australian workers aged 18-65 years. Using the web-based tool, OccIDEAS, semi-quantitative information was collected about exposures in the current job held by the respondent. Questions were addressed primarily at tasks undertaken rather than about self-reported exposures. A total of 307 (6.1%) of the 4993 included respondents were identified as probably being exposed to lead in the course of their work. Of these, almost all (96%) were male; about half worked in trades and technician-related occupations, and about half worked in the construction industry. The main tasks associated with probable exposures were, in decreasing order: soldering; sanding and burning off paint while painting old houses, ships, or bridges; plumbing work; cleaning up or sifting through the remains of a fire; radiator-repair work; machining metals or alloys containing lead; mining; welding leaded steel; and working at or using indoor firing ranges. Where information on control measures was available, inconsistent use was reported. Applied to the Australian working population, approximately 6.3% [95% confidence interval (CI) = 5.6-7.0] of all workers (i.e. 631000, 95% CI 566000-704000 workers) were estimated to have probable occupational exposure to lead. Lead remains an important exposure in many different occupational circumstances in Australia and probably other developed countries. This information can be used to support decisions on priorities for intervention and control

  6. Monitoring wild bird populations for lead exposure

    SciTech Connect

    Scheuhammer, A.M. )

    1989-07-01

    Delta-aminolevulinic acid dehydratase (ALA-d), an enzyme in the heme biosynthetic pathway is extremely sensitive to inhibition by lead (Pb). I evaluated the erythrocyte ALA-d activity ratio (the ratio between the fully restored enzyme activity and that measured without removing any inhibitory influence that might be present) as an indicator of Pb exposure in free-living birds. In the absence of elevated Pb exposure, birds, had comparable ALA-d activity ratios regardless of species, geographical location, or time of year sampled. The normal range of ratios for free-living species was similar to that for aviary-raised birds (1.0-1.3). Individuals with enzyme inhibition were readily identified. In blood collected from free-living mallards (Anas platyrhynchos), ALA-d activity ratios were better correlated with blood-Pb than were blood-protoporphyrin (PP) concentrations. At least 9.5% of mallards with blood-Pb>80 {mu}g/dL did not have elevated PP levels. Underestimation of Pb exposure did not occur using the ALA-d activity ratio method. The ALA-d activity ratio was as accurate as blood-Pb measurements for monitoring the relative degree of recent Pb exposure in the wild bird populations studied. Unlike blood-Pb analyses, ALA-d determinations do not require exposure in the wild bird populations studied. Unlike blood-Pb analyses, ALA-d determinations do not require exposure in the wild bird populations studied. Unlike blood-Pb analyses, ALA-d determinations do not require sophisticated and expensive instrumentation, and assays can be performed efficiently with minimal training.

  7. Prenatal lead exposure enhances methamphetamine sensitization in rats.

    PubMed

    Clifford, P Shane; Hart, Nigel; Thompson, Jeff; Buckman, Sam; Wellman, Paul J; Bratton, Gerald R; Nation, Jack R

    2009-08-01

    Adult female rats were exposed to lead-free sodium acetate via gavage [0 mg (vehicle control)] or to 16 mg lead as lead acetate for 30 days prior to breeding. Following confirmation of breeding, the female animals continued to be exposed to their respective doses throughout gestation and lactation. When weaned, 16 control and 16 lead-exposed offspring were placed on regular water and food (lead-exposure was discontinued) until postnatal day (PND) 70. At this time, one-half of the control animals and one-half of the lead-treatment animals received intraperitoneal (i.p.) injections of the vehicle (saline) for 10 successive days and the remaining animals in each exposure conditions received daily injections of 1.0 mg/kg (+)-methamphetamine (METH) for 10 days (N=8/group). Locomotion in automated chambers was monitored daily for 45 min post-injection. Subsequently, during dose-effect testing, all animals received consecutive daily i.p. injections of 0, 1.0, 2.0, and then 4.0 mg/kg METH. The results of the experiment showed that both control and lead-exposed animals exhibited heightened locomotor activity (i.e. behavioral sensitization) to the repeated administration of 1.0 mg/kg METH. More importantly, animals developmentally (perinatally) exposed to lead showed more rapid sensitization than did their control counterparts. These data indicate that early lead exposure increases sensitivity to the locomotor-stimulating effects of METH. In contrast, identically exposed lead animals exhibit diminished METH dose-effect responding when tested in an intravenous (i.v.) self-administration paradigm [Rocha A., Valles R., Bratton G.R., Nation J.R. Developmental lead exposure alters methamphetamine self-administration in the male rat: acquisition and reinstatement. Drug Alcohol Depend 2008a;95:23-29, Rocha A., Valles R., Hart N., Bratton G.R., Nation J.R. Developmental lead exposure attenuates methamphetamine dose-effect self-administration performance and progressive ratio

  8. Late Spontaneous Migration of a Dorsal Column Stimulator Paddle Lead.

    PubMed

    Li, Chao; Galgano, Michael A; Carter, David A

    2016-08-17

    The most frequently encountered complication of dorsal column stimulators is lead migration. The vast majority of these events are seen in the first few weeks to months. Late paddle lead migration is a very uncommon occurrence in this setting. We describe a case of a 51-year-old male with a history of reflex sympathetic dystrophy having undergone dorsal column stimulator insertion at the level of C1-C2. A good clinical benefit was appreciated in the postoperative period once the stimulator was turned on. Approximately six months postoperatively, the patient suddenly lost coverage. Radiographic imaging revealed that the lead had migrated caudally to the C3-C4 level. Subsequent revision surgery took place. This description highlights a common complication, but occurring outside the expected time frame after surgery.

  9. Late Spontaneous Migration of a Dorsal Column Stimulator Paddle Lead

    PubMed Central

    Li, Chao; Carter, David A

    2016-01-01

    The most frequently encountered complication of dorsal column stimulators is lead migration. The vast majority of these events are seen in the first few weeks to months. Late paddle lead migration is a very uncommon occurrence in this setting. We describe a case of a 51-year-old male with a history of reflex sympathetic dystrophy having undergone dorsal column stimulator insertion at the level of C1-C2. A good clinical benefit was appreciated in the postoperative period once the stimulator was turned on. Approximately six months postoperatively, the patient suddenly lost coverage. Radiographic imaging revealed that the lead had migrated caudally to the C3-C4 level. Subsequent revision surgery took place. This description highlights a common complication, but occurring outside the expected time frame after surgery. PMID:27672531

  10. SOURCES AND PATHWAYS OF LEAD EXPOSURE

    EPA Science Inventory

    Exposure is defined here as the amount of a substance that comes into contact with an absorbing surface during a specified period of time. The normal units of exposure are expressed as micrograms per day. The two components of exposure are the concentration of the substance in ...

  11. SOURCES AND PATHWAYS OF LEAD EXPOSURE

    EPA Science Inventory

    Exposure is defined here as the amount of a substance that comes into contact with an absorbing surface during a specified period of time. The normal units of exposure are expressed as micrograms per day. The two components of exposure are the concentration of the substance in ...

  12. Lead exposure in US worksites: A literature review and development of an occupational lead exposure database from the published literature

    PubMed Central

    Koh, Dong-Hee; Locke, Sarah J.; Chen, Yu-Cheng; Purdue, Mark P.; Friesen, Melissa C.

    2016-01-01

    Background Retrospective exposure assessment of occupational lead exposure in population-based studies requires historical exposure information from many occupations and industries. Methods We reviewed published US exposure monitoring studies to identify lead exposure measurement data. We developed an occupational lead exposure database from the 175 identified papers containing 1,111 sets of lead concentration summary statistics (21% area air, 47% personal air, 32% blood). We also extracted ancillary exposure-related information, including job, industry, task/location, year collected, sampling strategy, control measures in place, and sampling and analytical methods. Results Measurements were published between 1940 and 2010 and represented 27 2-digit standardized industry classification codes. The majority of the measurements were related to lead-based paint work, joining or cutting metal using heat, primary and secondary metal manufacturing, and lead acid battery manufacturing. Conclusions This database can be used in future statistical analyses to characterize differences in lead exposure across time, jobs, and industries. PMID:25968240

  13. Biological tests of lead absorption following a brief massive exposure

    SciTech Connect

    Williams, M.K.

    1984-07-01

    A contractor's man suffered a brief, massive exposure to lead fume by contaminating and then smoking hand-rolled cigarettes. His blood lead concentration rose very rapidly to very high levels, but zinc erythrocyte protoporphyrin, urinary lead, and urinary coproporphyrin did not. It is possible that only the blood lead concentration is of value in detecting brief massive exposure.

  14. MRI-induced heating of deep brain stimulation leads.

    PubMed

    Mohsin, Syed A; Sheikh, Noor M; Saeed, Usman

    2008-10-21

    The radiofrequency (RF) field used in magnetic resonance imaging is scattered by medical implants. The scattered field of a deep brain stimulation lead can be very intense near the electrodes stimulating the brain. The effect is more pronounced if the lead behaves as a resonant antenna. In this paper, we examine the resonant length effect. We also use the finite element method to compute the near field for (i) the lead immersed in inhomogeneous tissue (fat, muscle, and brain tissues) and (ii) the lead connected to an implantable pulse generator. Electric field, specific absorption rate and induced temperature rise distributions have been obtained in the brain tissue surrounding the electrodes. The worst-case scenario has been evaluated by neglecting the effect of blood perfusion. The computed values are in good agreement with in vitro measurements made in the laboratory.

  15. Racial differences in Urban children's environmental exposures to lead.

    PubMed Central

    Lanphear, B P; Weitzman, M; Eberly, S

    1996-01-01

    OBJECTIVES: This study explored whether differences in environmental lead exposures explain the racial disparity in children's blood lead levels. METHODS: Environmental sources of lead were identified for a random sample of 172 urban children. RESULTS: Blood lead levels were significantly higher among Black children. Lead-contamination of dust was higher in Black children's homes, and the condition of floors and interior paint was generally poorer. White children were more likely to put soil in their mouths and to suck their fingers, whereas Black children were more likely to put their mouths on window sills and to use a bottle. Major contributors to blood lead were interior lead exposures for Black children and exterior lead exposures for White children. CONCLUSIONS: Differences in housing conditions and exposures to lead-contaminated house dust contribute strongly to the racial disparity in urban children's blood lead levels. PMID:8876521

  16. Lead exposure in Canada geese of the Eastern Prairie Population

    USGS Publications Warehouse

    DeStefano, S.; Brand, C.J.; Rusch, D.H.; Finley, Daniel L.; Gillespie, M.M.

    1991-01-01

    We monitored lead exposure in Eastern Prairie Population Canada geese during summer-winter, 1986-1987 and 1987-1988 at 5 areas. Blood lead concentrations in geese trapped during summer at Cape Churchill Manitoba were below levels indicative of recent lead exposure (0.18 ppm). Geese exposed to lead (≥0.18 ppm blood lead) increased to 7.6% at Oak Hammock Wildlife Management Area (WMA), southern Manitoba, where lead shot was still in use, and to 10.0% at Roseau River WMA, northern Minnesota, when fall-staging geese were close to a source of lead shot in Manitoba. Proportion of birds exposed to lead dropped to <2% at Lac Qui Parle WMA, Minnesota, a steel shot zone since 1980. On the wintering grounds at Swan Lake National Wildlife Refuge in Missouri, 4.9% of all geese showed exposure to lead before the hunting season. Lead exposure rose to 10.0% after hunting ended and then decreased to 5.2% in late winter. Incidence of lead shot in gizzards and concentrations of lead in livers supported blood assay data. Soil samples indicated that lead shot continues to be available to geese at Swan Lake, even though the area was established as a non-toxic shot zone in 1978. Steel shot zones have reduced lead exposure in the Eastern Prairie Population, but lead shot persists in the environment and continues to account for lead exposure and mortality in Eastern Prairie Population Canada geese.

  17. Occupational and environmental human lead exposure in Brazil

    SciTech Connect

    Paoliello, M.M.B. . E-mail: monibas@sercomtel.com.br; De Capitani, E.M.

    2007-02-15

    The purpose of this paper is to present a review of data on assessment of exposure and adverse effects due to environmental and occupational lead exposure in Brazil. Epidemiological investigations on children lead exposure around industrial and mining areas have shown that lead contamination is an actual source of concern. Lead in gasoline has been phasing out since the 1980s, and it is now completely discontinued. The last lead mining and lead refining plant was closed in 1995, leaving residual environmental lead contamination which has recently been investigated using a multidisciplinary approach. Moreover, there are hundreds of small battery recycling plants and secondary smelting facilities all over the country, which produce focal urban areas of lead contamination. Current regulatory limits for workplace lead exposure have shown to be inadequate as safety limits according to a few studies carried out lately.

  18. Effects of low level exposure to lead on neurophysiological functions among lead battery workers.

    PubMed

    Kovala, T; Matikainen, E; Mannelin, T; Erkkilä, J; Riihimäki, V; Hänninen, H; Aitio, A

    1997-07-01

    Assessment of neurophysiological functions in workers with low level exposure to lead and evaluation of the efficacy of bone lead measurements in the prediction of effects of lead. Exposure to lead of 60 workers from a lead battery battery factory was estimated from historical blood lead measurements and analysis of lead in the tibial and calcaneal bones with x ray fluorescence. Peripheral and central nervous system functions were assessed by measuring conduction velocities, sensory distal latencies, sensory amplitudes, and vibration thresholds as well as by quantitative measurement of the absolute and relative powers and mean frequencies of different electroencephalograph (EEG) channels. Sensory amplitudes, and to a smaller degree sensory or motor conduction velocities, showed a negative correlation with long term exposure to lead, most clearly with integrated blood lead concentration and exposure time. Vibration thresholds measured in the arm were related to recent exposure to lead, those measured in the leg to long term exposure. The alpha and beta activities of the EEG were more abundant in subjects with higher long term exposure to lead. Calcaneal lead content reflected short term exposure, tibial lead content reflected long term exposure. Blood lead history showed a closer relation with effects of lead than the tibial or calcaneal lead concentrations. Vibratory thresholds, quantitative EEG, and to a smaller extent the sensory amplitude, provide sensitive measures of effects of lead in occupationally exposed adults. Most accurate estimates of health risks induced by lead can be obtained from a good history of blood lead measurements. If such a history of blood lead concentrations is not available, analysis of bone lead may be used for the assessment of health risks.

  19. Sacral nerve stimulation lead implantation using the o-arm

    PubMed Central

    2013-01-01

    Background Sacral neuromodulation operations have usually been performed based on 2D fluoro images. However, sacral nerve stimulation lead implantation may be challenging when the normal anatomy is confused by obesity or congenital anomalies. Thus the surgical navigation and intraoperative imaging methods could be helpful as those same methods have proven to be feasible methods for guiding other surgical operations. Our recent knowledge about the O-arm in trauma pelvic operations encouraged us to evaluate the usefulness of O-arm guided navigation in sacral neuromodulation. Similar navigation would be useful for complex sacral nerve stimulation lead implantations. Methods In this preliminary article we report our experience of utilizing the orthopedically optimized O-arm to implant the S3 stimulation electrode in a patient. The 3D O-arm imaging was performed intraoperatively under surgical navigation control. General anesthesia was used. The obtained 3D image dataset was registered automatically into the patient’s anatomy. The stimulation needle was guided and the tined lead electrode was implanted using navigation. Results The bony sacral structures were clearly visualized. Due to automatic registration, the navigation was practicable instantly after the O-arm scanning and operation could be performed successfully under navigation control. Conclusions To our knowledge, this is the first published tined lead implantation which was guided based on the surgical navigation and intraoperative O-arm images. In this case, the applied method was useful and helped the surgeon to demarcate the region of surgical interest. The method is slightly more invasive than the formal technique but could be an option in anatomically challenging cases and reoperations. However, further evaluation with larger patient series is required before definitive recommendations can be made. PMID:24131790

  20. Soil is an important pathway of human lead exposure.

    PubMed Central

    Mielke, H W; Reagan, P L

    1998-01-01

    This review shows the equal or greater importance of leaded gasoline-contaminated dust compared to lead-based paint to the child lead problem, and that soil lead, resulting from leaded gasoline and pulverized lead-based paint, is at least or more important than lead-based paint (intact and not pulverized) as a pathway of human lead exposure. Because lead-based paint is a high-dose source, the biologically relevant dosage is similar to lead in soil. Both lead-based paint and soil lead are associated with severe lead poisoning. Leaded gasoline and lead in food, but not lead-based paint, are strongly associated with population blood lead levels in both young children and adults. Soil lead and house dust, but not lead-based paint, are associated with population blood lead levels in children. Most soil lead and house dust are associated with leaded gasoline. Lead-based paint dust is associated with cases of renovation of either exterior or interior environments in which the paint was pulverized. Based upon the limited data to date, abatement of soil lead is more effective than abatement of lead-based paint in reducing blood lead levels of young children. About equal numbers of children under 7 years of age are exposed to soil lead and lead-based paint. Seasonality studies point to soil lead as the main source of population blood lead levels. Soil lead is a greater risk factor than lead-based paint to children engaged in hand-to-mouth and pica behavior. In summary, soil lead is important for addressing the population of children at risk of lead poisoning. When soil lead is acknowledged by regulators and the public health community as an important pathway of human lead exposure, then more effective opportunities for improving primary lead prevention can become a reality. Images Figure 1 PMID:9539015

  1. Lead Exposure and Cardiovascular Disease—A Systematic Review

    PubMed Central

    Navas-Acien, Ana; Guallar, Eliseo; Silbergeld, Ellen K.; Rothenberg, Stephen J.

    2007-01-01

    Objective This systematic review evaluates the evidence on the association between lead exposure and cardiovascular end points in human populations. Methods We reviewed all observational studies from database searches and citations regarding lead and cardiovascular end points. Results A positive association of lead exposure with blood pressure has been identified in numerous studies in different settings, including prospective studies and in relatively homogeneous socioeconomic status groups. Several studies have identified a dose–response relationship. Although the magnitude of this association is modest, it may be underestimated by measurement error. The hypertensive effects of lead have been confirmed in experimental models. Beyond hypertension, studies in general populations have identified a positive association of lead exposure with clinical cardiovascular outcomes (cardiovascular, coronary heart disease, and stroke mortality; and peripheral arterial disease), but the number of studies is small. In some studies these associations were observed at blood lead levels < 5 μg/dL. Conclusions We conclude that the evidence is sufficient to infer a causal relationship of lead exposure with hypertension. We conclude that the evidence is suggestive but not sufficient to infer a causal relationship of lead exposure with clinical cardiovascular outcomes. There is also suggestive but insufficient evidence to infer a causal relationship of lead exposure with heart rate variability. Public Health Implications These findings have immediate public health implications. Current occupational safety standards for blood lead must be lowered and a criterion for screening elevated lead exposure needs to be established in adults. Risk assessment and economic analyses of lead exposure impact must include the cardiovascular effects of lead. Finally, regulatory and public health interventions must be developed and implemented to further prevent and reduce lead exposure. PMID:17431501

  2. Measuring Lead Exposure in Infants, Children, and Other Sensitive Populations.

    ERIC Educational Resources Information Center

    National Academy of Sciences - National Research Council, Washington, DC.

    Adverse health effects from exposure to lead are now recognized to be among industrialized society's most important health problems. This report, prepared by the National Research Council's Committee on Measuring Lead Exposure in Critical Populations, concurs with new findings issued by the Centers for Disease Control which state that lead…

  3. Lead exposures in the human environment. Final report

    SciTech Connect

    Elias, R.W.

    1985-01-01

    Humans consume lead by inhaling air, drinking beverages, eating food and ingesting dust. The natural source of this lead is primarily soil. Anthropogenic sources are lead in gasoline, fossil fuels and industrial products and processes. Lead is ubiquitous in the human environment, and pinpointing the primary sources of lead in any particular environmental component is difficult. Nevertheless, our purpose is to describe the total exposure of humans to environmental lead and to determine the sources of lead contributing to this exposure. The total exposure is the total amount of lead consumed by ingestion and inhalation. Excluding lead exposure from choice or circumstance, a baseline level of potential human exposure can be defined for a normal individual eating a typical diet and living in a non-urban community remote from industrial sources of lead in a house without lead-based paints. Beyond this level, additive exposure factors can be determined for other environments (e.g. urban, occupational and smelter communities) and for certain habits and activities (e.g. pica, smoking, drinking and hobbies), with variation for age, sex or socioeconomic status.

  4. Trends in occupational lead exposure since the 1978 OSHA lead standard.

    PubMed

    Okun, Andrea; Cooper, Gregory; Bailer, A John; Bena, James; Stayner, Leslie

    2004-06-01

    The purpose of the study was to evaluate trends in occupational lead exposures throughout U.S. industry after the establishment of the general industry lead standard in 1978 and the construction industry standard in 1993. Lead exposure measurements collected by the Occupational Safety and Health Administration (OSHA) under their compliance and consultation programs were analyzed. Time trends in the distributions of exposure levels were evaluated graphically. Trends in the proportion of exposures above the OSHA permissible exposure limit (PEL) were analyzed using logistic regression models. The distribution of lead exposure levels declined over the study time period for general industry, but not for construction. The median exposure levels for general industry facilities decreased five- to tenfold. Logistic regression models reveal statistically significant declines in the odds of a lead exposure exceeding the PEL. This study provides evidence for relatively large decreases in lead exposure levels in general industry facilities over time. The study does not provide similar evidence for the construction industry. Given the limited number of years of data available since the implementation of the revised construction standard for lead, re-analysis of lead exposure levels within this industry would be worthwhile when more data become available.

  5. Lead exposure from battery recycling in Indonesia.

    PubMed

    Haryanto, Budi

    2016-03-01

    In Indonesia, more than 200 illegal used lead acid battery (ULAB) smelters are currently operating. Only a few health studies support the finding of lead-related symptoms and diseases among populations living near the smelters. To assess the blood lead levels (BLLs) and potential health impacts among the population surrounding ULAB recycling smelters, we evaluated health effects reported from 2003 to 2013, conducted focus group discussions with lead smelter owner/workers and a group of 35 female partners of smelter owners or workers not actively engaged in smelter work, and retook and measured BLLs. It was found that many children in the areas were having difficulty achieving high grades at school and having stunting or other problems with physical development. The average mean of BLLs increased by almost double in 2015, compared with in 2011. The risk of having hypertension, interference in the ability to make red blood cells in females occurred among 24% of respondents; Elevated blood pressure, hearing loss, and interference in the ability to make red bloods cell occurred in 20% of males; Kidney damage, infertility in male, nerve problems, including decreased sensation and decreased ability to move quickly occurred in 13%; Decreased ability to make red blood cells (20%), and; Frank anemia, decreased life-span, coma/seizures were experienced by 22%. The populations living in areas surrounding ULAB smelters are experiencing severe chronic health problems. It is recommended that the smelters must be moved and placed far away from the municipality.

  6. Incremental exposure facilitates adaptation to sensory rearrangement. [vestibular stimulation patterns

    NASA Technical Reports Server (NTRS)

    Lackner, J. R.; Lobovits, D. N.

    1978-01-01

    Visual-target pointing experiments were performed on 24 adult volunteers in order to compare the relative effectiveness of incremental (stepwise) and single-step exposure conditions on adaptation to visual rearrangement. The differences between the preexposure and postexposure scores served as an index of the adaptation elicited during the exposure period. It is found that both single-step and stepwise exposure to visual rearrangement elicit compensatory changes in sensorimotor coordination. However, stepwise exposure, when compared to single-step exposur in terms of the average magnitude of visual displacement over the exposure period, clearly enhances the rate of adaptation. It seems possible that the enhancement of adaptation to unusual patterns of sensory stimulation produced by incremental exposure reflects a general principle of sensorimotor function.

  7. Incremental exposure facilitates adaptation to sensory rearrangement. [vestibular stimulation patterns

    NASA Technical Reports Server (NTRS)

    Lackner, J. R.; Lobovits, D. N.

    1978-01-01

    Visual-target pointing experiments were performed on 24 adult volunteers in order to compare the relative effectiveness of incremental (stepwise) and single-step exposure conditions on adaptation to visual rearrangement. The differences between the preexposure and postexposure scores served as an index of the adaptation elicited during the exposure period. It is found that both single-step and stepwise exposure to visual rearrangement elicit compensatory changes in sensorimotor coordination. However, stepwise exposure, when compared to single-step exposur in terms of the average magnitude of visual displacement over the exposure period, clearly enhances the rate of adaptation. It seems possible that the enhancement of adaptation to unusual patterns of sensory stimulation produced by incremental exposure reflects a general principle of sensorimotor function.

  8. Preclinical evaluation of a miniaturized Deep Brain Stimulation electrode lead.

    PubMed

    Villalobos, Joel; Fallon, James B; McNeill, Peter M; Allison, Rachel K; Bibari, Olivier; Williams, Chris E; McDermott, Hugh J

    2015-01-01

    The effect of miniaturizing the electrode lead for Deep Brain Stimulation (DBS) therapy was investigated in this work. A direct comparison was made between a miniature lead (0.65 mm diameter) and a lead of standard size (1.3 mm). Acute in vivo implantation in two cat brains was performed to evaluate surgical trauma and confirm capacity to target thalamic nuclei. Insertion into a homogeneous gel model of neural tissue was used to compare insertion forces while visualizing the process. The standard size cannula, used first to guide lead insertion, required substantially higher insertion force compared with the miniature version and produced a significantly larger region of tissue disruption. The characteristic hemorrhage and edema extended 119-352 μm from the implanted track surface of the miniature lead and cannula, while these extended 311-571 μm for the standard size lead and cannula. A miniature DBS implant can reduce the extent of trauma and could potentially help improve neural function preservation after functional neurosurgery.

  9. Neurotoxicity and biomarkers of lead exposure: a review.

    PubMed

    Liu, Kang-sheng; Hao, Jia-hu; Zeng, Yu; Dai, Fan-chun; Gu, Ping-qing

    2013-09-01

    Appropriate selection and measurement of lead biomarkers of exposure are critically important for health care management purposes, public health decision making, and primary prevention synthesis. Lead is one of the neurotoxicants that seems to be involved in the etiology of psychologies. Biomarkers are generally classified into three groups: biomarkers of exposure, effect, and susceptibility.The main body compartments that store lead are the blood, soft tissues, and bone; the half-life of lead in these tissues is measured in weeks for blood, months for soft tissues, and years for bone. Within the brain, lead-induced damage in the prefrontal cerebral cortex, hippocampus, and cerebellum can lead to a variety of neurological disorders, such as brain damage, mental retardation, behavioral problems, nerve damage, and possibly Alzheimer's disease, Parkinsons disease, and schizophrenia. This paper presents an overview of biomarkers of lead exposure and discusses the neurotoxic effects of lead with regard to children and adults.

  10. Worker lead exposures during renovation of homes with lead-based paint

    SciTech Connect

    Sussell, A.; Gittleman, J.; Singal, M.

    1998-11-01

    The authors evaluated lead exposures among full-time home renovators and part-time volunteers working primarily in pre-1960 homes with lead-based paint. Potentially hazardous lead exposures were measured during two tasks: exterior dry scraping and wet scraping. Maximum exposures were 120 and 63 {micro}g/m{sup 3}, respectively. Exposures during other tasks, including general repair, weatherization, exterior scraping/painting, window replacement, demolition, and plumbing, were low, as were all 13 full-shift personal exposures. Blood lead levels for full-time workers ranged up to 17.5 {micro}g/dl, with a GM of 5.2 {micro}g/dl; the GM for volunteers was 3.2 {micro}g/dl. All of the paint samples collected from work surfaces had detectable amounts of lead, with 65% of the work surfaces tested having an average lead concentration of >0.5%.

  11. Lead exposure increases blood pressure by increasing angiotensinogen expression.

    PubMed

    Jiao, Jiandong; Wang, Miaomiao; Wang, Yiqing; Sun, Na; Li, Chunping

    2016-01-01

    Lead exposure can induce increased blood pressure. Several mechanisms have been proposed to explain lead-induced hypertension. Changes in angiotensinogen (AGT) expression levels or gene variants may also influence blood pressure. In this study, we hypothesized that AGT expression levels or gene variants contribute to lead-induced hypertension. A preliminary HEK293 cell model experiment was performed to analyze the association between AGT expression and lead exposure. In a population-based study, serum AGT level was measured in both lead-exposed and control populations. To further detect the influence of AGT gene single nucleotide polymorphisms (SNPs) in lead-induced hypertension, two SNPs (rs699 and rs4762) were genotyped in a case-control study including 219 lead-exposed subjects and 393 controls. Lead exposure caused an increase in AGT expression level in HEK 293 cell models (P < 0.001) compared to lead-free cells, and individuals exposed to lead had higher systolic and diastolic blood pressure (P < 0.001). Lead-exposed individuals had higher serum AGT levels compared to controls (P < 0.001). However, no association was found between AGT gene SNPs (rs699 and rs4762) and lead exposure. Nevertheless, the change in AGT expression level may play an important role in the development of lead-induced hypertension.

  12. Effect of Prenatal Exposure to Lead on Estrogen Action in the Prepubertal Rat Uterus

    PubMed Central

    Tchernitchin, Andrei N.; Gaete, Leonardo; Bustamante, Rodrigo; Báez, Aracelly

    2011-01-01

    Lead is a widely spread environmental pollutant known to affect both male and female reproductive systems in humans and experimental animals and causes infertility and other adverse effects. The present paper investigated the effects of prenatal exposure to lead on different parameters of estrogen stimulation in the uterus of the prepubertal rat. In prenatally and perinatally exposed rats, estrogen-induced endometrial eosinophilia, endometrial stroma edema, and eosinophil migration towards the endometrium, and uterine luminal epithelial hypertrophy are enhanced while several other responses to estrogen appear unchanged. These effects may contribute to decrease in fertility following prenatal exposure to lead. The striking difference between most of these effects of prenatal exposure and the previously reported effects of chronic exposure to lead suggests that prenatal exposure to lead may neutralize the effects of chronic exposure to lead, providing partial protection of cell function against the adverse effects of chronic exposure to lead. We propose that the mechanism involved, named imprinting or cell programming, persisted through evolution as a nongenetic adaptive mechanism to provide protection against long-term environmental variations that otherwise may cause the extinction of species not displaying this kind of adaptation. PMID:22263113

  13. The management of lead exposure in pediatric populations

    SciTech Connect

    Barker, P.O.; Lewis, D.A. )

    1990-12-01

    Chronically elevated lead levels are a common problem affecting children. Although this problem occurs most frequently in the inner city, no community is safe from excessive pediatric lead exposure. Screening by erythrocyte protoporphyrin is a sensitive early indicator of rising lead levels. A Centers for Disease Control report recommends that all children be screened starting at 9 to 12 months. A classification system of various lead levels helps determine proper treatment. Health care practitioners need to be well-informed about lead exposure and how it occurs in order to educate parents. 10 refs.

  14. Dietary exposure to lead of adults in Shenzhen city, China.

    PubMed

    Pan, Liubo; Wang, Zhou; Peng, Zhaoqiong; Liu, Guihua; Zhang, Huimin; Zhang, Jinzhou; Jiang, Jie; Pathiraja, Nimal; Xiao, Ying; Jiao, Rui; Huang, Wei

    2016-07-01

    Lead, a ubiquitous heavy metal, can be found in the environment and food. The present study is the first to estimate the lead dietary exposure of Shenzhen adults (≥ 20 years old) in various age-gender subgroups, and to assess the associated health risk. Food samples that represented the Shenzhen people's dietary pattern were collected and prepared for analysis. Lead was determined in 13 food groups using 276 individual cooked samples by inductively coupled plasma-mass spectrometry (ICP-MS). Dietary exposures were estimated by combining the analytical results with the local food consumption data of Shenzhen adults. The mean and 95th percentile lead exposure of Shenzhen adults were 0.59-0.73 and 0.75-0.94 μg kg(-1) bw day(-1), respectively. In all food groups, the highest lead exposure was from 'Eggs and their products' (42.4-51.6% of the total exposure); preserved eggs being the main contributor. The other major contributors to lead exposure of Shenzhen adults were 'Fish and seafood, and their products' (14.3-16.7% of the total exposure) and 'Vegetables and their products' (15.5-16.2% of the total exposure). The margin of exposure (MOE) approach was used for the risk assessment of lead, and the results showed that the risk was considered to be low in all age-gender groups for Shenzhen adults. However, having considered a number of toxic effects of lead, it is suggested that more efforts should be made to reduce the lead levels in foodstuff for Shenzhen adults.

  15. DIETARY EXPOSURE OF CHILDREN IN LEAD-LADEN ENVIRONMENTS

    EPA Science Inventory

    Children are the most susceptible population to lead exposure because of three interacting factors; they have more opportunity for contact with lead sources due to their activities, lead absorption occurs more readily in a child compared to an adult, and the child's development i...

  16. DIETARY EXPOSURE OF CHILDREN LIVING IN LEAD-LADEN ENVIRONMENTS

    EPA Science Inventory

    Children are the most susceptible population to lead exposure because of three interacting factors: they have more opportunity for contact with lead sources due to their activities; lead absorption occurs more readily in a child as compared to an adult; and the child's developmen...

  17. DIETARY EXPOSURE OF CHILDREN IN LEAD-LADEN ENVIRONMENTS

    EPA Science Inventory

    Children are the most susceptible population to lead exposure because of three interacting factors; they have more opportunity for contact with lead sources due to their activities, lead absorption occurs more readily in a child compared to an adult, and the child's development i...

  18. DIETARY EXPOSURE OF CHILDREN LIVING IN LEAD-LADEN ENVIRONMENTS

    EPA Science Inventory

    Children are the most susceptible population to lead exposure because of three interacting factors: they have more opportunity for contact with lead sources due to their activities; lead absorption occurs more readily in a child as compared to an adult; and the child's developmen...

  19. Biological monitoring of child lead exposure in the Czech Republic.

    PubMed Central

    Cikrt, M; Smerhovsky, Z; Blaha, K; Nerudova, J; Sediva, V; Fornuskova, H; Knotkova, J; Roth, Z; Kodl, M; Fitzgerald, E

    1997-01-01

    The area around the Pribram lead smelter has been recognized to be heavily contaminated by lead (Pb). In the early 1970s, several episodes of livestock lead intoxication were reported in this area; thereafter, several epidemiological and ecological studies focused on exposure of children. In contrast to earlier studies, the recent investigation (1992-1994) revealed significantly lower exposure to lead. From 1986-1990, recorded average blood lead levels were about 37.2 micrograms lead (Pb)/100 ml in an elementary school population living in a neighborhood close to the smelter (within 3 km of the plant). The present study, however, has found mean blood lead levels of 11.35 micrograms/100 ml (95% CI = 9.32; 13.82) among a comparable group of children. In addition to blood lead, tooth lead was used to assess exposure among children. Statistically significant differences (p < 0.05) were observed between the geometric mean tooth lead level of 6.44 micrograms Pb/g (n = 13; 95% CI = 3.95; 10.50) in the most contaminated zone and 1.43 micrograms Pb/g (n = 35; 95% CI = 1.11; 1.84) in zones farther away from the point source. Both biomarkers, blood and tooth lead levels, reflect a similar pattern of lead exposure in children. This study has attempted a quantitative assessment of risk factors associated with elevated lead exposure in the Czech Republic. Content of lead in soil, residential distance from the smelter, consumption of locally grown vegetables or fruits, drinking water from local wells, the mother's educational level, cigarette consumption among family members, and the number of children in the family were factors positively related (p < 0.05) to blood lead levels. The resulting blood lead level was found to be inversely proportional to the child's age. Images Figure 1. PMID:9189705

  20. Chronic lead exposure reduces junctional resistance at an electrical synapse.

    PubMed

    Audesirk, G; Audesirk, T

    1984-01-01

    Both acute and chronic lead exposure have been found to inhibit transmission at chemical synapses, possibly by interfering with inward calcium current. We have found that chronic lead exposure slightly reduces input resistance and greatly reduces the junctional resistance between two strongly electrically coupled neurons in the pond snail Lymnaea stagnalis. The net effect is to increase the strength of electrical coupling. A reduction in gap junctional resistance would also be expected to increase the flow of small molecules between cells. However, Lucifer Yellow injections did not reveal dye-coupling between the cells. Lead exposure also increases the capacitance of the neurons.

  1. Effect of exposure to lead on reproduction in male rats

    SciTech Connect

    Piasek, M.; Kostial, K.

    1987-09-01

    The objective of present study was to determine the effect of chronic oral exposure to different levels of lead on male reproductive performance since oral exposure data are more relevant to human environmental exposure. Additionally, most previous results have been obtained after parenteral administration of lead. These experiments were performed on rats by using the incidence of pregnancy to assess male fertility and litter size and pup weight as indicators of the lead effect on perinatal development. Similar parameters were used in reproduction studies by other authors.

  2. Epigenetics, obesity and early-life cadmium or lead exposure.

    PubMed

    Park, Sarah S; Skaar, David A; Jirtle, Randy L; Hoyo, Cathrine

    2017-01-01

    Obesity is a complex and multifactorial disease, which likely comprises multiple subtypes. Emerging data have linked chemical exposures to obesity. As organismal response to environmental exposures includes altered gene expression, identifying the regulatory epigenetic changes involved would be key to understanding the path from exposure to phenotype and provide new tools for exposure detection and risk assessment. In this report, we summarize published data linking early-life exposure to the heavy metals, cadmium and lead, to obesity. We also discuss potential mechanisms, as well as the need for complete coverage in epigenetic screening to fully identify alterations. The keys to understanding how metal exposure contributes to obesity are improved assessment of exposure and comprehensive establishment of epigenetic profiles that may serve as markers for exposures.

  3. Environmental exposure to lead (Pb) and variations in its susceptibility.

    PubMed

    Kim, Jina; Lee, Youngeun; Yang, Mihi

    2014-01-01

    Based on exposure frequency and intrinsic toxicity, lead (Pb) ranks one of the highest priority toxic materials. Continuous regulation of environmental Pb exposure has contributed to dramatically diminished exposure levels of Pb, for example, blood level of Pb. However, the safety level of Pb is not established, as low-level exposure to Pb still shows severe toxicity in high susceptible population and late onset of some diseases from early exposure. In the present study, we focused on food-borne Pb exposure and found broad variations in Pb exposure levels via food among countries. In addition, there are genetic or ethnical variations in Pb-targeted and protective genes. Moreover, various epigenetic alterations were induced by Pb poisoning. Therefore, we suggest a systemic approach including governmental (public) and individual prevention from Pb exposure with continuous biological monitoring and genetic or epigenetic consideration.

  4. Childhood Lead Exposure from Battery Recycling in Vietnam.

    PubMed

    Daniell, William E; Van Tung, Lo; Wallace, Ryan M; Havens, Deborah J; Karr, Catherine J; Bich Diep, Nguyen; Croteau, Gerry A; Beaudet, Nancy J; Duy Bao, Nguyen

    2015-01-01

    Battery recycling facilities in developing countries can cause community lead exposure. To evaluate child lead exposure in a Vietnam battery recycling craft village after efforts to shift home-based recycling outside the village. This cross-sectional study evaluated 109 children in Dong Mai village, using blood lead level (BLL) measurement, parent interview, and household observation. Blood samples were analyzed with a LeadCare II field instrument; highest BLLs (≥45 μg/dL) were retested by laboratory analysis. Surface and soil lead were measured at 11 households and a school with X-ray fluorescence analyzer. All children had high BLLs; 28% had BLL ≥45 μg/dL. Younger age, family recycling, and outside brick surfaces were associated with higher BLL. Surface and soil lead levels were high at all tested homes, even with no recycling history. Laboratory BLLs were lower than LeadCare BLLs, in 24 retested children. In spite of improvements, lead exposure was still substantial and probably associated with continued home-based recycling, legacy contamination, and workplace take-home exposure pathways. There is a need for effective strategies to manage lead exposure from battery recycling in craft villages. These reported BLL values should be interpreted cautiously, although the observed field-laboratory discordance may reflect bias in laboratory results.

  5. Childhood Lead Exposure from Battery Recycling in Vietnam

    PubMed Central

    Van Tung, Lo; Wallace, Ryan M.; Havens, Deborah J.; Karr, Catherine J.; Bich Diep, Nguyen; Croteau, Gerry A.; Beaudet, Nancy J.; Duy Bao, Nguyen

    2015-01-01

    Background. Battery recycling facilities in developing countries can cause community lead exposure. Objective. To evaluate child lead exposure in a Vietnam battery recycling craft village after efforts to shift home-based recycling outside the village. Methods. This cross-sectional study evaluated 109 children in Dong Mai village, using blood lead level (BLL) measurement, parent interview, and household observation. Blood samples were analyzed with a LeadCare II field instrument; highest BLLs (≥45 μg/dL) were retested by laboratory analysis. Surface and soil lead were measured at 11 households and a school with X-ray fluorescence analyzer. Results. All children had high BLLs; 28% had BLL ≥45 μg/dL. Younger age, family recycling, and outside brick surfaces were associated with higher BLL. Surface and soil lead levels were high at all tested homes, even with no recycling history. Laboratory BLLs were lower than LeadCare BLLs, in 24 retested children. Discussion. In spite of improvements, lead exposure was still substantial and probably associated with continued home-based recycling, legacy contamination, and workplace take-home exposure pathways. There is a need for effective strategies to manage lead exposure from battery recycling in craft villages. These reported BLL values should be interpreted cautiously, although the observed field-laboratory discordance may reflect bias in laboratory results. PMID:26587532

  6. Immunological effects of occupational exposure to lead (Review).

    PubMed

    Fenga, Concettina; Gangemi, Silvia; Di Salvatore, Valentina; Falzone, Luca; Libra, Massimo

    2017-05-01

    It is well-known that occupational and environmental exposure to several factors, including benzene, heavy metals, chemicals and mineral fibers, is associated with the risk of developing a great number of diseases. Numerous studies have been carried out in order to investigate the mechanisms of toxicity of these substances, with particular regard to the possible toxic effects on the immune system. However, little is known about the influence of heavy metals, such as lead, on the immune system in human populations. Lead is a heavy metal still used in many industrial activities. Human exposure to lead can induce various biological effects depending upon the level and duration of exposure, such as toxic effects on haematological, cardiovascular, nervous and reproductive systems. Several studies demonstrated that exposure to lead is associated to toxic effects also on the immune system, thus increasing the incidence of allergy, infectious disease, autoimmunity or cancer. However, the effects of lead exposure on the human immune system are not conclusive, mostly in occupationally exposed subjects; nevertheless some immunotoxic abnormalities induced by lead have been suggested. In particular, in vivo, in vitro and ex vivo lead is able to improve T helper 2 (Th2) cell development affecting Th1 cell proliferation. Further studies are required to better understand the mechanisms of lead immunotoxicity and the ability of lead to affect preferentially one type of immune response.

  7. The Yugoslavia Prospective Study of environmental lead exposure.

    PubMed Central

    Factor-Litvak, P; Wasserman, G; Kline, J K; Graziano, J

    1999-01-01

    The Yugoslavia Prospective Study of environmental lead exposure has studied the associations between exposure to lead and pregnancy outcomes; childhood neuropsychological, behavioral, and physical development; and hematologic, renal, and cardiovascular function. The cohort comprises 577 children born to women recruited at midpregnancy in two towns in Kosovo, Yugoslavia; one town is the site of a lead smelter, refinery, and battery plant and the other is 25 miles away and relatively unexposed. A sample of these children has been followed at 6-month intervals through 7.5 years of age. Blood lead concentrations ranged from 1 to 70 microg/dl. Exposure to lead was not associated with adverse pregnancy outcomes. Exposure was associated with modest decrements in intelligence, small increases in blood pressure, higher risks of proteinuria, small increases in behavior problems, and perturbed hematopoiesis. Only at low level exposures (i.e., <16 microg/dl) were small associations with decreased height found. We discuss methodological problems that may hinder causal interpretation of these data, namely, use of blood lead concentration as an exposure measure, confounding, and town-specific associations. We conclude that while reported associations are small, collectively they lend support to the notion that lead is a toxicant with numerous adverse health effects. Images Figure 1 PMID:9872712

  8. Association between Prenatal Lead Exposure and Blood Pressure in Children

    PubMed Central

    Zhang, Aimin; Sánchez, Brisa N.; Ettinger, Adrienne S.; Park, Sung Kyun; Cantonwine, David; Schnaas, Lourdes; Wright, Robert O.; Lamadrid-Figueroa, Hector; Tellez-Rojo, Martha Maria

    2011-01-01

    Background: Lead exposure in adults is associated with hypertension. Altered prenatal nutrition is associated with subsequent risks of adult hypertension, but little is known about whether prenatal exposure to toxicants, such as lead, may also confer such risks. Objectives: We investigated the relationship of prenatal lead exposure and blood pressure (BP) in 7- to 15-year-old boys and girls. Methods: We evaluated 457 mother–child pairs, originally recruited for an environmental birth cohort study between 1994 and 2003 in Mexico City, at a follow-up visit in 2008–2010. Prenatal lead exposure was assessed by measurement of maternal tibia and patella lead using in vivo K-shell X-ray fluorescence and cord blood lead using atomic absorption spectrometry. BP was measured by mercury sphygmomanometer with appropriate-size cuffs. Results: Adjusting for relevant covariates, maternal tibia lead was significantly associated with increases in systolic BP (SBP) and diastolic BP (DBP) in girls but not in boys (p-interaction with sex = 0.025 and 0.007 for SBP and DBP, respectively). Among girls, an interquartile range increase in tibia lead (13 μg/g) was associated with 2.11-mmHg [95% confidence interval (CI): 0.69, 3.52] and 1.60-mmHg (95% CI: 0.28, 2.91) increases in SBP and DBP, respectively. Neither patella nor cord lead was associated with child BP. Conclusions: Maternal tibia lead, which reflects cumulative environmental lead exposure and a source of exposure to the fetus, is a predisposing factor to higher BP in girls but not boys. Sex-specific adaptive responses to lead toxicity during early-life development may explain these differences. PMID:21947582

  9. Biomarkers of lead exposure and DNA methylation within retrotransposons.

    PubMed

    Wright, Robert O; Schwartz, Joel; Wright, Rosalind J; Bollati, Valentina; Tarantini, Letizia; Park, Sung Kyun; Hu, Howard; Sparrow, David; Vokonas, Pantel; Baccarelli, Andrea

    2010-06-01

    DNA methylation is an epigenetic mark that regulates gene expression. Changes in DNA methylation within white blood cells may result from cumulative exposure to environmental metals such as lead. Bone lead, a marker of cumulative exposure, may therefore better predict DNA methylation than does blood lead. In this study we compared associations between lead biomarkers and DNA methylation. We measured global methylation in participants of the Normative Aging Study (all men) who had archived DNA samples. We measured patella and tibia lead levels by K-X-Ray fluorescence and blood lead by atomic absorption spectrophotometry. DNA samples from blood were used to determine global methylation averages within CpG islands of long interspersed nuclear elements-1 (LINE-1) and Alu retrotransposons. A mixed-effects model using repeated measures of Alu or LINE-1 as the dependent variable and blood/bone lead (tibia or patella in separate models) as the primary exposure marker was fit to the data. Overall mean global methylation (+/- SD) was 26.3 +/- 1.0 as measured by Alu and 76.8 +/- 1.9 as measured by LINE-1. In the mixed-effects model, patella lead levels were inversely associated with LINE-1 (beta = -0.25; p < 0.01) but not Alu (beta = -0.03; p = 0.4). Tibia lead and blood lead did not predict global methylation for either Alu or LINE-1. Patella lead levels predicted reduced global DNA methylation within LINE-1 elements. The association between lead exposure and LINE-1 DNA methylation may have implications for the mechanisms of action of lead on health outcomes, and also suggests that changes in DNA methylation may represent a biomarker of past lead exposure.

  10. The identification of lead ammunition as a source of lead exposure in First Nations: the use of lead isotope ratios.

    PubMed

    Tsuji, Leonard J S; Wainman, Bruce C; Martin, Ian D; Sutherland, Celine; Weber, Jean-Philippe; Dumas, Pierre; Nieboer, Evert

    2008-04-15

    The use of lead shotshell to hunt water birds has been associated with lead-contamination in game meat. However, evidence illustrating that lead shotshell is a source of lead exposure in subsistence hunting groups cannot be deemed definitive. This study seeks to determine whether lead shotshell constitutes a source of lead exposure using lead isotope ratios. We examined stable lead isotope ratios for lichens, lead shotshell and bullets, and blood from residents of Fort Albany and Kashechewan First Nations, and the City of Hamilton, Ontario, Canada. Data were analyzed using ANOVA and regression analyses. ANOVA of isotope ratios for blood revealed significant differences with respect to location, but not sex. Hamilton differed from both Kashechewan and Fort Albany; however, the First Nations did not differ from each other. ANOVA of the isotope ratios for lead ammunition and lichens revealed no significant differences between lichen groups (north and south) and for the lead ammunition sources (pellets and bullets). A plot of (206)Pb/(204)Pb and (206)Pb/(207)Pb values illustrated that lichens and lead ammunition were distinct groupings and only the 95% confidence ellipse of the First Nations group overlapped that of lead ammunition. In addition, partial correlations between blood-lead levels (adjusted for age) and isotope ratios revealed significant (p<0.05) positive correlations for (206)Pb/(204)Pb and (206)Pb/(207)Pb, and a significant negative correlation for (208)Pb/(206)Pb, as predicted if leaded ammunition were the source of lead exposure. In conclusion, lead ammunition was identified as a source of lead exposure for First Nations people; however, the isotope ratios for lead shotshell pellets and bullets were indistinguishable. Thus, lead-contaminated meat from game harvested with lead bullets may also be contributing to the lead body burden.

  11. Excessive exposure stimulates epicormic branching in young northern hardwoods

    Treesearch

    Barton M. Blum

    1963-01-01

    Sudden and excessive exposure of northern hardwood trees often causes growth responses that degrade tree quality, injuries that lead to tree deterioration, or both. The most sensitive and visible tree reaction to increased exposure is the formation of epicormic branches. Such branches may arise along the tree bole from either dormant or adventitious buds in response to...

  12. Control of excessive lead exposure in radiator repair workers

    SciTech Connect

    Not Available

    1991-03-01

    In 1988, 83 automotive repair workers with blood lead levels (BLLs) greater than 25 micrograms/dL were reported to state health departments in the seven states that collaborated with CDC's National Institute for Occupational Safety and Health (NIOSH) in maintaining registries of elevated BLLs in adults. In 18 (22%) of these 83 persons, BLLs were greater than 50 micrograms/dL. Among automotive repair workers for whom a job category was specified, radiator repair work was the principal source of lead exposure. The major sources of exposure for radiator repair workers are lead fumes generated during soldering and lead dust produced during radiator cleaning. This report summarizes current BLL surveillance data for radiator repair workers and describes three control technologies that are effective in reducing lead exposures in radiator repair shops.

  13. Control of excessive lead exposure in radiator repair workers.

    PubMed

    1991-03-01

    In 1988, 83 automotive repair workers with blood lead levels (BLLs) greater than 25 micrograms/dL were reported to state health departments in the seven states that collaborated with CDC's National Institute for Occupational Safety and Health (NIOSH) in maintaining registries of elevated BLLs in adults. In 18 (22%) of these 83 persons, BLLs were greater than 50 micrograms/dL. Among automotive repair workers for whom a job category was specified, radiator repair work was the principal source of lead exposure. The major sources of exposure for radiator repair workers are lead fumes generated during soldering and lead dust produced during radiator cleaning. This report summarizes current BLL surveillance data for radiator repair workers and describes three control technologies that are effective in reducing lead exposures in radiator repair shops.

  14. Exposure to lead in stained glass work. An environmental evaluation.

    PubMed

    Pant, B C; Harrison, J R; Long, G W; Gupta, S

    1994-01-25

    An environmental evaluation was conducted to determine lead exposure in a group of crafts people who produce stained glass and Tiffany glass. The environmental evaluation consisted of air sampling for potential lead emissions from solder and of work area dusts. In addition, the completion of a questionnaire, observation of work practices and noting of other details relevant to hazardous exposures were carried out. Lead concentrations in air were found to be well below the ACGIH TLV-TWA of 150 micrograms/m3. High lead concentrations were found in the work area dust samples. Exposure to high concentrations of lead could occur by ingestion as a result of neglect of basic hygiene precautions.

  15. Lead exposure and neurobehavior development in later infancy

    SciTech Connect

    Dietrich, K.N.; Succop, P.A.; Bornschein, R.L.; Hammond, P.B.; Buncher, C.R.; Berger, O. ); Krafft, K.M. )

    1990-11-01

    A prospective methodology was used to assess the neurobehavioral effects of fetal and postnatal lead exposure during the first 2 years of life. Lead was measured in whole blood prenatally in mothers and at quarterly intervals in the infant. Prenatal blood lead levels were low (mean = 8.0 {mu}g/dL). However, approximately 25% of the study infants had at least one serial blood lead level of 25 {mu}g/dL or higher during the second year of life. Multiple regression and structural equation analyses revealed statistically significant relationships between prenatal and neonatal blood lead level and 3- and 6-month Bayley Mental and/or Psychomotor Development Index. However, by 2 years of age, no statistically significant effects of prenatal or postnatal lead exposure on neurobehavioral development could be detected. Data consistent with the hypothesis that a postnatal neurobehavioral growth catch-up occurred in infants exposed fetally to higher levels of lead are presented.

  16. Lead exposure and neurobehavioral development in later infancy.

    PubMed Central

    Dietrich, K N; Succop, P A; Bornschein, R L; Krafft, K M; Berger, O; Hammond, P B; Buncher, C R

    1990-01-01

    A prospective methodology was used to assess the neurobehavioral effects of fetal and postnatal lead exposure during the first 2 years of life. Lead was measured in whole blood prenatally in mothers and at quarterly intervals in the infant. Prenatal blood lead levels were low (mean = 8.0 micrograms/dL). However, approximately 25% of the study infants had at least one serial blood lead level of 25 micrograms/dL or higher during the second year of life. Multiple regression and structural equation analyses revealed statistically significant relationships between prenatal and neonatal blood lead level and 3- and 6-month Bayley Mental and/or Psychomotor Development Index. However, by 2 years of age, no statistically significant effects of prenatal or postnatal lead exposure on neurobehavioral development could be detected. Data consistent with the hypothesis that a postnatal neurobehavioral growth catch-up occurred in infants exposed fetally to higher levels of lead are presented. PMID:2088739

  17. Study and models of total lead exposures of battery workers.

    PubMed

    Chavalitnitikul, C; Levin, L; Chen, L C

    1984-12-01

    In an attempt to establish a more realistic and reliable model for relating environmental exposure measurements to the biological indices of exposure, a study was undertaken to quantify the total sources of lead exposure among lead storage battery workers. In addition to the usual personal and area lead air sampling, quantitative and repeatable measurements of removable lead from work surfaces and the workers' hands and faces were obtained daily for ten consecutive work days in the pasting and battery assembly departments. Mathematical correlations of blood lead and zinc protoporphyrin (ZPP) levels as the dependent variable with the lead exposure sources were derived and demonstrated most strongly as log-log relationships. Statistical analyses by computer programming indicated that the airborne, hand, facial and work surface levels have a high degree of inter-correlation with a very significant positive individual correlation with blood lead levels and a somewhat lower correlation with ZPP. The results suggest that contaminated personal and work surfaces may play a more significant role in toxic occupational and environmental exposures, generally, than had heretofore been demonstrated or suspected.

  18. Site-specific lead exposure from lead pellet ingestion in sentinel mallards

    USGS Publications Warehouse

    Rocke, T.E.; Brand, C.J.; Mensik, John G.

    1997-01-01

    We monitored lead poisoning from the ingestion of spent lead pellets in sentinel mallards (Anas platyhrynchos) at the Sacramento National Wildlife Refuge (SNWR), Willows, California for 4 years (1986-89) after the conversion to steel shot for waterfowl hunting on refuges in 1986. Sentinel mallards were held in 1.6-ha enclosures in 1 hunted (P8) and 2 non-hunted (T19 and TF) wetlands. We compared site-specific rates of lead exposure, as determined by periodic measurement of blood lead concentrations, and lead poisoning mortality between wetlands with different lead pellet densities, between seasons, and between male and female sentinels. In 1986, the estimated 2-week rate of lead exposure was significantly higher (P < 0.005) in P8 (43.8%), the wetland with the highest density of spent lead pellets (>2,000,000 pellets/ha), than in those with lower densities of lead pellets, T19 (18.1%; 173,200 pellets/ha) and TF (0.9%; 15,750 pellets/ha). The probability of mortality from lead poisoning was also significantly higher (P < 0.01) in sentinel mallards enclosed in P8 (0.25) than T19 (0) and TF (0) in 1986 and remained significantly higher (P < 0.001) during the 4-year study. Both lead exposure and the probability of lead poisoning mortality in P8 were significantly higher (P < 0.001) in the fall of 1986 (43.8%; 0.25), before hunting season, than in the spring of 1987 (21.6%; 0.04), after hunting season. We found no significant differences in the rates of lead exposure or lead poisoning mortality between male and female sentinel mallards. The results of this study demonstrate that in some locations, lead exposure and lead poisoning in waterfowl will continue to occur despite the conversion to steel shot for waterfowl hunting.

  19. Site-specific lead exposure from lead pellet ingestion in sentinel mallards

    USGS Publications Warehouse

    Rocke, T.E.; Brand, C.J.; Mensik, John G.

    1997-01-01

    We monitored lead poisoning from the ingestion of spent lead pellets in sentinel mallards (Anas platyhrynchos) at the Sacramento National Wildlife Refuge (SNWR), Willows, California for 4 years (1986-89) after the conversion to steel shot for waterfowl hunting on refuges in 1986. Sentinel mallards were held in 1.6-ha enclosures in 1 hunted (P8) and 2 non-hunted (T19 and TF) wetlands. We compared site-specific rates of lead exposure, as determined by periodic measurement of blood lead concentrations, and lead poisoning mortality between wetlands with different lead pellet densities, between seasons, and between male and female sentinels. In 1986, the estimated 2-week rate of lead exposure was significantly higher (P < 0.005) in P8 (43.8%), the wetland with the highest density of spent lead pellets (>2,000,000 pellets/ha), than in those with lower densities of lead pellets, T19 (18.1%; 173,200 pellets/ha) and TF (0.9%; 15,750 pellets/ha). The probability of mortality from lead poisoning was also significantly higher (P < 0.01) in sentinel mallards enclosed in P8 (0.25) than T19 (0) and TF (0) in 1986 and remained significantly higher (P < 0.001) during the 4-year study. Both lead exposure and the probability of lead poisoning mortality in P8 were significantly higher (P < 0.001) in the fall of 1986 (43.8%; 0.25), before hunting season, than in the spring of 1987 (21.6%; 0.04), after hunting season. We found no significant differences in the rates of lead exposure or lead poisoning mortality between male and female sentinel mallards. The results of this study demonstrate that in some locations, lead exposure and lead poisoning in waterfowl will continue to occur despite the conversion to steel shot for waterfowl hunting.

  20. Association of Cumulative Lead Exposure with Parkinson’s Disease

    PubMed Central

    Weisskopf, Marc G.; Weuve, Jennifer; Nie, Huiling; Saint-Hilaire, Marie-Helene; Sudarsky, Lewis; Simon, David K.; Hersh, Bonnie; Schwartz, Joel; Wright, Robert O.; Hu, Howard

    2010-01-01

    Background Research using reconstructed exposure histories has suggested an association between heavy metal exposures, including lead, and Parkinson’s disease (PD), but the only study that used bone lead, a biomarker of cumulative lead exposure, found a nonsignificant increase in risk of PD with increasing bone lead. Objectives We sought to assess the association between bone lead and PD. Methods Bone lead concentrations were measured using 109Cd excited K-shell X-ray fluorescence from 330 PD patients (216 men, 114 women) and 308 controls (172 men, 136 women) recruited from four clinics for movement disorders and general-community cohorts. Adjusted odds ratios (ORs) for PD were calculated using logistic regression. Results The average age of cases and controls at bone lead measurement was 67 (SD = 10) and 69 (SD = 9) years of age, respectively. In primary analyses of cases and controls recruited from the same groups, compared with the lowest quartile of tibia lead, the OR for PD in the highest quartile was 3.21 [95% confidence interval (CI), 1.17–8.83]. Results were similar but slightly weaker in analyses restricted to cases and controls recruited from the movement disorders clinics only (fourth-quartile OR = 2.57; 95% CI, 1.11–5.93) or when we included controls recruited from sites that did not also contribute cases (fourth-quartile OR = 1.91; 95% CI, 1.01–3.60). We found no association with patella bone lead. Conclusions These findings, using an objective biological marker of cumulative lead exposure among typical PD patients seen in our movement disorders clinics, strengthen the evidence that cumulative exposure to lead increases the risk of PD. PMID:20807691

  1. Association of cumulative lead exposure with Parkinson's disease.

    PubMed

    Weisskopf, Marc G; Weuve, Jennifer; Nie, Huiling; Saint-Hilaire, Marie-Helene; Sudarsky, Lewis; Simon, David K; Hersh, Bonnie; Schwartz, Joel; Wright, Robert O; Hu, Howard

    2010-11-01

    Research using reconstructed exposure histories has suggested an association between heavy metal exposures, including lead, and Parkinson's disease (PD), but the only study that used bone lead, a biomarker of cumulative lead exposure, found a nonsignificant increase in risk of PD with increasing bone lead. We sought to assess the association between bone lead and PD. Bone lead concentrations were measured using 109Cd excited K-shell X-ray fluorescence from 330 PD patients (216 men, 114 women) and 308 controls (172 men, 136 women) recruited from four clinics for movement disorders and general-community cohorts. Adjusted odds ratios (ORs) for PD were calculated using logistic regression. The average age of cases and controls at bone lead measurement was 67 (SD = 10) and 69 (SD = 9) years of age, respectively. In primary analyses of cases and controls recruited from the same groups, compared with the lowest quartile of tibia lead, the OR for PD in the highest quartile was 3.21 [95% confidence interval (CI), 1.17-8.83]. Results were similar but slightly weaker in analyses restricted to cases and controls recruited from the movement disorders clinics only (fourth-quartile OR = 2.57; 95% CI, 1.11-5.93) or when we included controls recruited from sites that did not also contribute cases (fourth-quartile OR = 1.91; 95% CI, 1.01-3.60). We found no association with patella bone lead. These findings, using an objective biological marker of cumulative lead exposure among typical PD patients seen in our movement disorders clinics, strengthen the evidence that cumulative exposure to lead increases the risk of PD.

  2. Parental occupational lead exposure and lead concentration of newborn cord blood

    SciTech Connect

    Wang, J.D.; Shy, W.Y.; Chen, J.S.; Yang, K.H.; Hwang, Y.H.

    1989-01-01

    The purpose of this study was to determine the influence of parental occupational lead exposure on the lead levels of newborn cord blood in the Taipei area. From September 1984 to June 1985, 5,000 pregnant women voluntarily participated in the study at the Taipei Municipal Maternal and Child Hospital. Each woman was interviewed regarding her and her husband's occupational exposures; 2,948 successfully delivered healthy newborns, and cord blood samples were obtained using Terumo Venoject, and 242 samples were analyzed by graphite furnace atomic absorption spectrometry using an Instrumentation Laboratory 251 instrument. Nine cord blood samples were from newborns with both parents exposed, 26 samples had maternal exposure only, 105 samples had paternal exposure only, and 102 were nonexposed. The results showed that the average lead level of cord blood with both parents exposed was 8.9 +/- 2.9 micrograms%, maternal exposure 9.0 +/- 3.8 micrograms%, paternal exposure 8.3 +/- 3.4 micrograms%, and 6.9 +/- 3.2 micrograms% in the nonexposed group. There were significant differences between the nonexposed and the maternal exposure groups, and also between the nonexposed and paternal exposure groups. All 26 maternal exposures were from lead soldering operations. Multivariate analysis revealed that, after control of father's exposure status, newborn cord blood lead level increased 0.27 micrograms% for each hour the mother spent on lead soldering during a normal working day, thus suggesting that soldering during pregnancy may be hazardous to newborns. Paternal contribution to the cord blood lead levels seemed to be through either working at home with the pregnant mother also at home or bringing work clothes home for laundering.

  3. Early childhood lead exposure and exceptionality designations for students.

    PubMed

    Miranda, Marie Lynn; Maxson, Pamela; Kim, Dohyeong

    2010-01-01

    The achievement gap continues to be an important educational issue, with disadvantaged groups exhibiting poorer school performance. Recently, literature has shown that even very low levels of early lead exposure affect cognitive and academic performance. As individuals at the lower end of the socioeconomic spectrum are more likely to be exposed to lead, this exposure may be an important contributor to the achievement gap. In this paper, we explore whether early childhood blood lead levels are associated with membership in exceptionality designation groups. In addition, we examine the racial and socioeconomic composition of these exceptional groups. Data from the North Carolina Childhood Lead Poisoning Prevention Program surveillance registry were linked at the individual child level to educational outcomes available through the North Carolina Education Research Data Center. Designation into exceptionality groups was obtained from the end-of-grade (EOG) data. Both standard bivariate and multivariate analyses were employed. Bivariate analyses indicate that blood lead levels and reading EOG scores differ by exceptionality, as well as by race and enrollment in free/reduced lunch. Logistic regression confirmed the relationship between blood lead levels and likelihood of exceptionality. Contextual factors - enrollment in the free/reduced lunch program, race, and parental education - are also significant with regard to exceptionality. This study demonstrates that early childhood lead exposure significantly influences the likelihood of being designated exceptional. These results provide additional evidence that early childhood lead exposure is a significant explanator of the achievement gap.

  4. Artificial Christmas trees: how real are the lead exposure risks?

    PubMed

    Maas, Richard P; Patch, Steven C; Pandolfo, Tamara J

    2004-12-01

    Exposure to lead has long been recognized as a major public health issue in the United States and other industrialized nations. The health risks associated with low lead levels mean that consumer products (such as those made from polyvinyl chloride [PVC] plastic, which often incorporates lead as a stabilizer) with even moderate lead exposure risks could be dangerous. The purpose of the experiments reported in this article was to test for lead exposure from artificial Christmas trees made of PVC, which are now present in an estimated 50 million U.S. households. The first phase of experimentation tested artificial Christmas trees in the laboratory for lead content in branches, lead transfer from hand contact, and lead dust levels under the tree. The second phase was based on a field-testing survey of households with artificial Christmas trees. Results from these experiments show that, while the average artificial Christmas tree does not present a significant exposure risk, in the worst-case scenarios a substantial health risk to young children is quite possible.

  5. Multimedia lead exposure and associated risk assessment in Dhaka, Bangladesh

    SciTech Connect

    Sarwar, M.

    1998-12-31

    Motor vehicles consume the largest amount of leaded gasoline in Bangladesh. The number of vehicles and fuel consumption have increased significantly in recent years. These vehicles, which are believed to be the major sources of lead emissions in Dhaka, may cause an excessive level of lead exposure in children. The paper describes the results of a study conducted to determine risk associated with the multimedia lead exposure for children in Dhaka. Specifically, data related to lead content in air and soil in Dhaka were collected and used to estimate the blood lead levels in children. The Integrated Exposure Uptake Biokinetics Model, developed by the United States Environmental Protection Agency (USEPA), was used. Bangladesh is yet to adopt any blood lead standards. The results of the study indicated that the model predicted geometric blood lead levels in children in Dhaka are significantly below the blood lead standard recommended by the World Health Organization (WHO). It was also found that children in Dhaka are not expected to contain blood lead levels higher than the WHO recommended standard.

  6. Biochemical diagnosis of occupational exposure to lead toxicity

    SciTech Connect

    Somashekaraiah, B.V.; Venkaiah, B.; Prasad, A.R.K. )

    1990-02-01

    Lead has been shown to interfere with the biosynthesis of heme in a number of in vitro systems and in experimental animals as well as in human beings. Several steps of the heme biosynthetic chain are subject to the toxic effects of lead. ALA- dehydratase and Ferrochelatase, in particular, are two enzymes which are strongly inhibited by lead, leading to decreased heme synthesis, a constituent of hemoglobin. The inhibition of ALA dehydratase in the red blood cells by lead is generally recognized as the most sensitive index of the individuals exposure to this environmental chemical. Earlier reports show that the determination of blood lead content (Pb-B), zinc protoporphyrin levels and erythrocyte Aminolevulinic acid dehydratase (ALA.D) are widely used as biological indicators for lead toxicity. Hence, the aim of the present study was to screen for occupational exposure to lead in the workers of three different occupations and correlate their blood lead levels with erythrocyte ALA.D and total blood porphyrin content as biochemical indicators of lead exposure.

  7. Maternal lead exposure and the secondary sex ratio.

    PubMed

    Jarrell, John F; Weisskopf, Marc G; Weuve, Jennifer; Téllez-Rojo, Maria Martha; Hu, Howard; Hernández-Avila, Mauricio

    2006-07-01

    A reduction in the secondary sex ratio may be associated with exposure to environmental toxicants. Little data exists relating this outcome to lead exposure, a well-known reproductive toxicant. We studied 1980 women having singleton births from 1994 to 1995 and from 1997 to 2001 who participated in a cohort study of lead exposure and infant outcomes in Mexico City. Levels of lead were measured in maternal and cord blood using graphite furnace atomic absorption spectroscopy, and levels of lead in maternal patella and tibia bone (a reflection of cumulative exposure) were measured using noninvasive K-X-ray fluorescence measurements. Using logistic regression models, we evaluated the relations of these measures to secondary sex ratio in the offspring, adjusting for maternal age, parity and year of infants' birth. We found no consistent association between any of the lead measures and secondary sex ratio. Results were unchanged when we adjusted for infants' year of birth, maternal age and parity. Despite a large sample size and the use of sensitive biomarkers, we did not find evidence that maternal and fetal lead exposure is associated with a lower secondary sex ratio among newborns.

  8. Environmental lead exposure: a public health problem of global dimensions.

    PubMed Central

    Tong, S.; von Schirnding, Y. E.; Prapamontol, T.

    2000-01-01

    Lead is the most abundant of the heavy metals in the Earth's crust. It has been used since prehistoric times, and has become widely distributed and mobilized in the environment. Exposure to and uptake of this non-essential element have consequently increased. Both occupational and environmental exposures to lead remain a serious problem in many developing and industrializing countries, as well as in some developed countries. In most developed countries, however, introduction of lead into the human environment has decreased in recent years, largely due to public health campaigns and a decline in its commercial usage, particularly in petrol. Acute lead poisoning has become rare in such countries, but chronic exposure to low levels of the metal is still a public health issue, especially among some minorities and socioeconomically disadvantaged groups. In developing countries, awareness of the public health impact of exposure to lead is growing but relatively few of these countries have introduced policies and regulations for significantly combating the problem. This article reviews the nature and importance of environmental exposure to lead in developing and developed countries, outlining past actions, and indicating requirements for future policy responses and interventions. PMID:11019456

  9. A discriminant analysis of neuropsychological effect of low lead exposure.

    PubMed

    Boey, K W; Jeyaratnam, J

    1988-05-01

    The purpose of this study is to determine the contribution of psychological tests in discriminating neuropsychological effects of low lead exposure. The sample consists of 49 workers occupationally exposed to lead and a control group of 36 non-exposed workers. Their performance on various neuropsychological measures was subject to a discriminant analysis using the SPSS DISCRIMINANT subprogramme. The results indicate that simple reaction time, Digit Symbol (WAIS) and Trail-Making Test (Part A) provide the best combination of tests for the detection of neurotoxic effect of low lead exposure.

  10. Environmental lead exposure to toll booth workers in Hong Kong

    SciTech Connect

    Tan, T.C.; Wong, L.T.L.; Lam, C.W.K.

    1988-01-01

    A survey of workers in the Lion Rock Tunnel toll booths was conducted, as they were regarded as a high risk group in lead exposure due to high density of vehicular traffic. The exposure of the workers to lead was determined by continuous sapling of air around the breathing zone of workers inside the booths. Blood lead concentration of 50 workers showed a mean of 0.65 {mu}mol/L and the mean urine lead concentration was 0.14 {mu}mol/L. Other tests, such as urinary amino-levulinic acid (ALA), erythrocyte zinc protoporphyrin (ZnPP) and hemoglobin concentration (Hb), were also preformed. The blood lead concentrations and other biological parameters of the toll-booth workers were acceptable and may be attributed to the recent legislation to lower the lead content in petrol and to the good preventive measures taken by the management.

  11. Reassessment of lead exposure in New Jersey using GIS technology.

    PubMed

    Guthe, W G; Tucker, R K; Murphy, E A; England, R; Stevenson, E; Luckhardt, J C

    1992-12-01

    In order to prevent children's exposure to lead, a variety of sources must be controlled. The New Jersey Department of Environmental Protection and Energy (NJDEPE) is using its Geographic Information System to identify areas within Newark, East Orange, and Irvington, New Jersey, where there may be greater environmental exposure to lead. Sensitive populations are identified through the U.S. Bureau of the Census information. Blood screening data provided by the New Jersey Department of Health (NJDOH) provide reported patterns of elevated blood lead in the study area. Comparisons of these spatial patterns will assist the NJDEPE in its soil sampling activities and lead exposure research, will provide information for public education, and will provide valuable information on sections of the study area where further screening and public education may be needed.

  12. Lead uptake and lead loss in the fresh water field crab, Barytelphusa guerini, on exposure to organic and inorganic lead

    SciTech Connect

    Tulasi, S.J.; Yasmeen, R.; Reddy, C.P.; Rao, J.V.R.

    1987-07-01

    Lead is a heavy metal which is widely used in paint industry, pigments, dyes, electrical components and electronics, plastic chemicals and in various other things. Since some of the lead salts are soluble in water, lead presents a potential threat to aquatic organisms. Studies dealing with invertebrates include those on mortality, growth and lead uptake in Lymnaea palustris and bioaccumulation of heavy metals in oysters and mussels. Little information exists regarding the effect of lead on the fresh water crustaceans. Hence the present investigation has been undertaken to study the uptake and loss of lead on exposure to subtoxic levels or organic and inorganic lead.

  13. Environmental urban lead exposure and blood lead levels in children of Mexico City.

    PubMed Central

    Romieu, I; Carreon, T; Lopez, L; Palazuelos, E; Rios, C; Manuel, Y; Hernandez-Avila, M

    1995-01-01

    Lead contamination is now a leading public health problem in Mexico. However, there are few data on the lead content of various environmental sources, and little is known about the contribution of these sources to the total lead exposure in the population of children residing in Mexico City. We conducted a cross-sectional study in a random sample of 200 children younger than 5 years of age who lived in one of two areas of Mexico City. Environmental samples of floor, window, and street dust, paint, soil, water, and glazed ceramics were obtained from the participants' households, as well as blood samples and dirt from the hands of the children. Blood lead levels ranged from 1 to 31 micrograms/dl with a mean of 9.9 micrograms/dl (SD 5.8 micrograms/dl). Forty-four percent of the children 18 months of age or older had blood lead levels exceeding 10 micrograms/dl. The lead content of environmental samples was low, except in glazed ceramic. The major predictors of blood lead levels were the lead content of the glazed ceramics used to prepare children's food, exposure to airborne lead due to vehicular emission, and the lead content of the dirt from the children's hands. We conclude that the major sources of lead exposure in Mexico City could be controlled by adequate public health programs to reinforce the use of unleaded gasoline and to encourage production and use of unleaded cookware instead of lead-glazed ceramics. PMID:8605853

  14. Environmental urban lead exposure and blood lead levels in children of Mexico City.

    PubMed

    Romieu, I; Carreon, T; Lopez, L; Palazuelos, E; Rios, C; Manuel, Y; Hernandez-Avila, M

    1995-11-01

    Lead contamination is now a leading public health problem in Mexico. However, there are few data on the lead content of various environmental sources, and little is known about the contribution of these sources to the total lead exposure in the population of children residing in Mexico City. We conducted a cross-sectional study in a random sample of 200 children younger than 5 years of age who lived in one of two areas of Mexico City. Environmental samples of floor, window, and street dust, paint, soil, water, and glazed ceramics were obtained from the participants' households, as well as blood samples and dirt from the hands of the children. Blood lead levels ranged from 1 to 31 micrograms/dl with a mean of 9.9 micrograms/dl (SD 5.8 micrograms/dl). Forty-four percent of the children 18 months of age or older had blood lead levels exceeding 10 micrograms/dl. The lead content of environmental samples was low, except in glazed ceramic. The major predictors of blood lead levels were the lead content of the glazed ceramics used to prepare children's food, exposure to airborne lead due to vehicular emission, and the lead content of the dirt from the children's hands. We conclude that the major sources of lead exposure in Mexico City could be controlled by adequate public health programs to reinforce the use of unleaded gasoline and to encourage production and use of unleaded cookware instead of lead-glazed ceramics.

  15. Prenatal lead exposure and childhood blood pressure and kidney function.

    PubMed

    Skröder, Helena; Hawkesworth, Sophie; Moore, Sophie E; Wagatsuma, Yukiko; Kippler, Maria; Vahter, Marie

    2016-11-01

    Exposure to lead, a common environmental pollutant, is known to cause cardiovascular and nephrotoxic effects in adults. Potential effects of early-life lead exposure on these functions are, however, less well characterized. To assess blood pressure and kidney function in preschool-aged children in relation to prenatal lead exposure. This prospective study in rural Bangladesh measured children's systolic and diastolic blood pressure in triplicate at the follow-up at 4.5±0.11 years. Their kidney function was assessed by the estimated glomerular filtration rate (eGFR), calculated based on serum cystatin C concentrations, and by kidney volume, measured by sonography. Exposure to lead was assessed by concentrations in the mothers' blood (erythrocyte fraction; Ery-Pb) in gestational weeks (GW) 14 and 30, the effects of which were evaluated separately in multivariable-adjusted linear regression analyses. We found no associations between maternal exposure to lead [n~1500 for GW14 and 700 for GW30] and children's blood pressure or eGFR. However, we found an inverse association between late gestation lead and kidney volume, although the sample size was limited (n=117), but not with early gestation lead (n=573). An increase of 85µg/kg in Ery-Pb (median concentration at GW30) was associated with a 6.0cm(3)/m(2) decrease in kidney volume (=0.4SD; p=0.041). After stratifying on gender, there seemed to be a somewhat stronger association in girls. Prenatal lead exposure may cause long-lasting effects on the kidney. This warrants follow-up studies in older children, as well as additional studies in other populations. Copyright © 2016. Published by Elsevier Inc.

  16. Toddler temperament and prenatal exposure to lead and maternal depression.

    PubMed

    Stroustrup, Annemarie; Hsu, Hsiao-Hsien; Svensson, Katherine; Schnaas, Lourdes; Cantoral, Alejandra; Solano González, Maritsa; Torres-Calapiz, Mariana; Amarasiriwardena, Chitra; Bellinger, David C; Coull, Brent A; Téllez-Rojo, Martha M; Wright, Robert O; Wright, Rosalind J

    2016-06-16

    Temperament is a psychological construct that reflects both personality and an infant's reaction to social stimuli. It can be assessed early in life and is stable over time Temperament predicts many later life behaviors and illnesses, including impulsivity, emotional regulation and obesity. Early life exposure to neurotoxicants often results in developmental deficits in attention, social function, and IQ, but environmental predictors of infant temperament are largely unknown. We propose that prenatal exposure to both chemical and non-chemical environmental toxicants impacts the development of temperament, which can itself be used as a marker of risk for maladaptive neurobehavior in later life. In this study, we assessed associations among prenatal and early life exposure to lead, mercury, poverty, maternal depression and toddler temperament. A prospective cohort of women living in the Mexico City area were followed longitudinally beginning in the second trimester of pregnancy. Prenatal exposure to lead (blood, bone), mercury, and maternal depression were assessed repeatedly and the Toddler Temperament Scale (TTS) was completed when the child was 24 months old. The association between each measure of prenatal exposure and performance on individual TTS subscales was evaluated by multivariable linear regression. Latent profile analysis was used to classify subjects by TTS performance. Multinomial regression models were used to estimate the prospective association between prenatal exposures and TTS performance. 500 mother-child pairs completed the TTS and had complete data on exposures and covariates. Three latent profiles were identified and categorized as predominantly difficult, intermediate, or easy temperament. Prenatal exposure to maternal depression predicted increasing probability of difficult toddler temperament. Maternal bone lead, a marker of cumulative exposure, also predicted difficult temperament. Prenatal lead exposure modified this association

  17. Brainstem auditory evoked potentials in children with lead exposure.

    PubMed

    Alvarenga, Katia de Freitas; Morata, Thais Catalani; Lopes, Andrea Cintra; Feniman, Mariza Ribeiro; Corteletti, Lilian Cassia Bornia Jacob

    2015-01-01

    Earlier studies have demonstrated an auditory effect of lead exposure in children, but information on the effects of low chronic exposures needs to be further elucidated. To investigate the effect of low chronic exposures of the auditory system in children with a history of low blood lead levels, using an auditory electrophysiological test. Contemporary cross-sectional cohort. Study participants underwent tympanometry, pure tone and speech audiometry, transient evoked otoacoustic emissions, and brainstem auditory evoked potentials, with blood lead monitoring over a period of 35.5 months. The study included 130 children, with ages ranging from 18 months to 14 years, 5 months (mean age 6 years, 8 months ± 3 years, 2 months). The mean time-integrated cumulative blood lead index was 12 μg/dL (SD ± 5.7, range: 2.433). All participants had hearing thresholds equal to or below 20 dBHL and normal amplitudes of transient evoked otoacoustic emissions. No association was found between the absolute latencies of waves I, III, and V, the interpeak latencies I-III, III-V, and I-V, and the cumulative lead values. No evidence of toxic effects from chronic low lead exposures was observed on the auditory function of children living in a lead contaminated area. Copyright © 2014 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

  18. The intersection of aggregate-level lead exposure and crime.

    PubMed

    Boutwell, Brian B; Nelson, Erik J; Emo, Brett; Vaughn, Michael G; Schootman, Mario; Rosenfeld, Richard; Lewis, Roger

    2016-07-01

    Childhood lead exposure has been associated with criminal behavior later in life. The current study aimed to analyze the association between elevated blood lead levels (n=59,645) and crime occurrence (n=90,433) across census tracts within St. Louis, Missouri. Longitudinal ecological study. Saint Louis, Missouri. Blood lead levels. Violent, Non-violent, and total crime at the census tract level. Spatial statistical models were used to account for the spatial autocorrelation of the data. Greater lead exposure at the census-tract level was associated with increased violent, non-violent, and total crime. In addition, we examined whether non-additive effects existed in the data by testing for an interaction between lead exposure and concentrated disadvantage. Some evidence of a negative interaction emerged, however, it failed to reach traditional levels of statistical significance (supplementary models, however, revealed a similar negative interaction that was significant). More precise measurements of lead exposure in the aggregate, produced additional evidence that lead is a potent predictor of criminal outcomes. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. Exposure of migrant bald eagles to lead in prairie Canada.

    PubMed

    Miller, M J; Wayland, M E; Bortolotti, G R

    2001-01-01

    The prevalence of elevated exposure to lead was assessed in a migrant population of bald eagles (Haliaeetus leucocephalus) at a waterfowl staging area in the southern portion of the Canadian prairies, from September to November, 1992-1995. Of 103 eagles, 8% exhibited blood lead (PbB) concentrations suggestive of elevated exposure to lead (> or = 0.200 microgram ml-1 wet wt.). PbB concentrations in eagles from the study area ranged from < 0.01 to 0.585 microgram ml-1, while those of nestling eagles from a reference site indicated normal or background exposure (< 0.01 microgram ml-1). No differences in the prevalence of elevated exposure were detected among genders or age classes (0.5- and > or = 1.5-year-old birds) (P > 0.05). The prevalence of elevated exposure was significantly greater in November than in October (21.7 vs. 3.8%) (all years: chi 2Y = 5.75, P = 0.017). Eagles with shotshell pellets in the digestive tract did not have accompanying high PbB concentrations. The prevalence of elevated lead exposure in this study was low in comparison to other areas in North America. Potential biases in the trapping technique as they relate to interpreting the results are addressed.

  20. Exposure to lead and human health in the Czech Republic.

    PubMed

    Bláha, K; Bencko, V; Cikrt, M

    1996-12-01

    The aim of presented review is to address the most relevant issues related to the health effects caused by the human exposure to lead, as they have been recognized in Czech Republic in the period of 1992-1994 within the framework of the National Integrated Programme on Environment and Health (NIPEH) approved in 1992 and supported by WHO-European Centre for Environment and Health (WHO-ECEH), Bilthoven, The Netherlands and by the Government of the Netherlands. Basic sources of environment exposure to lead are identified and the fate of lead in the individual compartments of the environment is discussed. Relevant methods used for the exposure evaluation are summarized and the highest-risk group of population is defined. Attention is being paid to the effects of the long-term exposure to low lead levels, while other exposure settings are intentionally omitted. Interventional measures developed in the Czech Republic in attempt to reduce the environmental exposure are introduced. Instead of presenting specific data, current state-of-art and general trends are presented; list of references tries to combine the internationally recognized studies with those coming from national sources.

  1. Window renovation and exposure to lead--an observational study.

    PubMed

    Mason, Howard; Gallagher, Frank; Sen, Dil

    2005-12-01

    Renovation of windows in old houses has recently established itself as an industry. A recognizable occupational lead exposure exists, which has not been studied previously. To compare lead exposure amongst window renovators with other groups of lead-exposed workers. Using blood lead results measured at the Health and Safety Laboratory (HSL), Sheffield, comparisons were made between three cohorts: window renovation workers, all male workers monitored by HSL during the period 1999-2001 and 63 male subjects involved in chemical paint-stripping of wood. Both the window renovation and the wood-stripping cohorts show significantly higher blood lead distributions than the 'all workers' cohort (P < 0.001). A similar pattern was also found for comparison of the prevalence of subjects above the UK suspension level of 60 microg/dl (2.89 microM) (window renovation, P < 0.001; wood-stripping, P < 0.0001). Blood lead results at or above the suspension level in wood-strippers were significantly higher compared to window renovators (P = 0.034). Window renovation is shown to present a potential for significant lead exposure, and suspension from work under The Control of Lead at Work Regulations 2002. Two groups of risk factors predominate: the well-documented potential for release of lead from old paint, and the peripatetic nature of the work.

  2. Stimulating creativity via the exposure to other people's ideas.

    PubMed

    Fink, Andreas; Koschutnig, Karl; Benedek, Mathias; Reishofer, Gernot; Ischebeck, Anja; Weiss, Elisabeth M; Ebner, Franz

    2012-11-01

    As it is the case in brainstorming, each single idea a person generates to a specific problem may stimulate new ideas or solutions in others. In this fMRI study, we investigate the effects of cognitive stimulation via the exposure to other people's ideas on the originality of generated ideas. Participants are requested to generate alternative uses of conventional everyday objects subsequent to a short cognitive stimulation intervention in which they are exposed to other ideas, which were either common or highly original. In a control condition, meaningless pseudowords are shown. Results suggest that cognitive stimulation via common or moderately creative ideas was effective in improving creativity. At the neurophysiological level, temporo-parietal brain regions (primarily right-hemispheric) turned out to be particularly sensitive to cognitive stimulation, possibly indicating that cognitive stimulation via relevant memory cues results in a state of heightened focused attention to memory that facilitates efficient retrieval and recombination of existing knowledge. Copyright © 2011 Wiley Periodicals, Inc.

  3. Occupational exposure to airborne lead in Brazilian police officers.

    PubMed

    Rocha, Ernesto Díaz; Sarkis, Jorge E Souza; Carvalho, Maria de Fátima H; Santos, Gerson Vechio Dos; Canesso, Claudemir

    2014-07-01

    Shooting with lead-containing ammunition in indoor firing ranges is a known source of lead exposure in adults. Police officers may be at risk of lead intoxication when regular training shooting exercises are yearly mandatory to law enforcement officers. Effects on health must be documented, even when low-level elemental (inorganic) lead exposure is detected. Forty police officers (nineteen cadets and twenty-one instructors) responded to a questionnaire about health, shooting habits, and potential lead exposure before a training curse. Blood samples were collected and analyzed for blood lead level (BLL) before and after a three days training curse. The mean BLL for the instructors' group was 5.5 μg/dL ± 0.6. The mean BLL for the cadets' group before the training was 3.3 μg/dL ± 0.15 and after the training the main BLL was 18.2 μg/d L± 1.5. Samples were analyzed by Inductively Coupled Plasma Mass Spectrometer (ICP-MS). All the participants in the training curse had significantly increased BLL (mean increment about 15 μg/dL) after the three days indoor shooting season. In conclusion, occupational lead exposure in indoor firing ranges is a source of lead exposure in Brazilian police officers, and appears to be a health risk, especially when heavy weapons with lead-containing ammunition are used in indoor environments during the firing training seasons. Copyright © 2013 Elsevier GmbH. All rights reserved.

  4. Take home lead exposure in children of oil field workers.

    PubMed

    Khan, Fahad

    2011-06-01

    Childhood lead poisoning is a major, preventable environmental health problem. While residential lead-based paint and lead contaminated dust and soil are the most common sources of childhood lead poisoning, children can also be at risk if they live with an adult with a job or hobby that involves exposure to lead. Currently, the Oklahoma Childhood Lead Poisoning Prevention Program (OCLPPP) has a small number of cases of "take home" lead exposure in children of oil field workers. These workers may come in contact with a threading compound, "pipe dope" that can contain large amounts of lead. Workers handling this product may be exposed to lead by not following safety instructions. Additionally workers may not be provided the facilities to shower and change out of the contaminated clothing before leaving the work location. The OCLPPP recommends employers and worksites should consider effective alternative options like lead free biodegradable pipe dopes or dope free connections to prevent workers and their families from adverse health effects associated with lead.

  5. Lead exposure from backyard chicken eggs: a public health risk?

    PubMed

    Bautista, Adrienne C; Puschner, Birgit; Poppenga, Robert H

    2014-09-01

    Although the USA has made significant strides in reducing lead exposure, new and emerging sources are raising cause for public concern. Recent reports of finding lead in eggs from chickens raised in urban gardens has highlighted the need to consider the potential health risks of consuming eggs from backyard chickens. Following the detection of 0.33 μg/g lead in the edible portion of eggs submitted for lead analysis from a backyard chicken owner, further investigation was conducted to determine the source and extent of lead exposure in the flock. Several birds, almost two dozen eggs, and environmental samples were submitted to the California Animal Health and Food Safety Laboratory for further testing. Lead was detected in the blood, liver, kidney, and bone at varying concentrations in all birds but was not detected in the muscle tissue. All egg shells contained detectable amounts of lead, while only a little over half of the edible portion of the eggs contained lead. The detected concentrations in the edible portion approached or exceeded the recommended threshold of lead consumption per day that should not be exceeded by young children if a child consumed one average-sized egg. Peeling paint from a wooded structure adjacent to the flock's coop was the likely lead source containing 3,700 μg/g lead. Thus, removal of the chickens from the source and periodic testing of eggs for lead were recommended. This case illustrates the need for consumers and health care workers to be aware of potential sources for lead exposure such as backyard chickens.

  6. The cultural parameters of lead poisoning: A medical anthropologist's view of intervention in environmental lead exposure

    SciTech Connect

    Trotter, R.T. II )

    1990-11-01

    This article identifies four culturally shaped sources of lead exposure in human societies: modern and historic technological sources; food habits; culturally defined health beliefs; and beauty practices. Examples of these potential sources of lead poisoning are presented from current cultures. They include the use of lead-glazed cooking pottery in Mexican-American households; folk medical use of lead in Hispanic, Arabic, South Asian, Chinese, and Hmong communities; as well as the use of lead as a cosmetic in the Near East, Southeast Asia, and South Asia. Four interacting cultural conditions that create barriers to the reduction of lead exposure and lead poisoning are identified and discussed. These are knowledge deficiencies, communication resistance, cultural reinterpretations, and incongruity of explanatory models.

  7. The cultural parameters of lead poisoning: a medical anthropologist's view of intervention in environmental lead exposure.

    PubMed Central

    Trotter, R T

    1990-01-01

    This article identifies four culturally shaped sources of lead exposure in human societies: modern and historic technological sources: food habits; culturally defined health beliefs; and beauty practices. Examples of these potential sources of lead poisoning are presented from current cultures. They include the use of lead-glazed cooking pottery in Mexican-American households; folk medical use of lead in Hispanic, Arabic, South Asian, Chinese, and Hmong communities; as well as the use of lead as a cosmetic in the Near East, Southeast Asia, and South Asia. Four interacting cultural conditions that create barriers to the reduction of lead exposure and lead poisoning are identified and discussed. These are knowledge deficiencies, communication resistance, cultural reinterpretations, and incongruity of explanatory models. PMID:2088759

  8. Lead exposure in firearms instructors of the Italian State Police.

    PubMed

    Di Lorenzo, L; Borraccia, V; Corfiati, Marisa; Mantineo, G A; Caciari, Tiziana; Marino, Marina; Soleo, L

    2010-01-01

    Several studies evaluated exposure to lead in relatively small groups of firearms instructors and shooters, mainly operating at indoor ranges. To assess the levels of lead exposure in a large sample of firearms instructors of the Italian State Police (SP) operating at either indoor or outdoor ranges. A crosssectional study was conducted in firearms instructors working in indoor (No. 188) and outdoor (No. 188) ranges compared with 170 foodplant workers. The personal and work characteristics and current blood lead (Pb-B) levels were evaluated The concentrations of environmental lead (Pb-E) were measured using personal samplers in 6 indoor and 6 outdoor firing ranges. The Pb-B levels in the two groups of firearms instructors were well below the ACGIH BEI, but significantly higher than in food plant workers. In the entire study sample the Pb-B level was seen to be influenced by age and job group. An excess risk of having Pb-B >100 microg/l was found in indoor range instructors and in those with greater job seniority. Pb-E <25 pg/m3 was measured in all the firing ranges examined. The low Pb-B and Pb-E levels assessed are the result of primary and secondary prevention interventions carried out over the years by the Italian State Police. The current Pb-B levels also seemed to be poorly influenced by higher past environmental and/or occupational lead exposure. In fact a certain number of firearms instructors, mainly operating at indoor ranges and with greater job seniority, had Pb-B levels consistent with occupational exposure to lead. Environmental and biological monitoring of lead exposure and specific health surveillance are therefore still necessary in this job group topreventpossible adverse health effects of lead even at low doses.

  9. Tremor secondary to neurotoxic exposure: mercury, lead, solvents, pesticides.

    PubMed

    Lucchini, Roberto G; Hashim, Dana

    2015-01-01

    Lead, mercury, solvents, and pesticide exposures are common in certain occupations and may cause nervous system dysfunction. Tremors may be the herald manifestation among a constellation of acute toxicity signs and symptoms. However, since tremors may also be the only sign on clinical presentation and since tremors also occur in other diseases, relating tremors to a specific occupational exposure can be challenging. Diagnosis of tremor etiology must be based on other findings on physical exam, laboratory results, and/or imaging. Discerning whether the tremor resulted from the occupational environment versus other etiologies requires knowledge of potential exposure sources, additional detail in history taking, and support of other health and industrial professionals. Reduction or removal from the exposure source remains the key first step in treating patients suffering from tremor that had resulted from occupational exposure toxicity.

  10. Selenium protects reproductive system and foetus development in a rat model of gestational lead exposure.

    PubMed

    Shen, W; Chen, J; Yin, J; Wang, S-L

    2016-01-01

    Lead is a common environmental contaminant. Lead accumulation in the body is especially dangerous for pregnant women and newborns. Selenium is a trace element which may rectify the damaging effects of lead. Here we tested potential protective effects of selenium against gestational lead exposure. Pregnant SD rats were exposed to 200 mg/L of lead acetate (given with water), with or without sodium selenite supplementation (2-8 mg/kg/day via intragastric administration). Pregnant rats not exposed to lead or selenium served as control animals. The outcomes in pregnant rats were serum lead and selenium levels, reproductive hormone (follicle-stimulating hormone, luteinizing hormone, prolactin, oestradiol, progesterone) levels, and uterine and ovarian morphological changes. The outcomes in the offspring were sex differentiation, survival rates (day 21 after birth), weight (days 0-35 after birth), weight of reproductive organs, and puberty onset (foreskin separation or vaginal opening). Selenium supplementation dose-dependently decreased serum lead levels, rectified reproductive hormone levels, and attenuated reproductive morphological changes caused by lead exposure. Lead exposure did not affect sex differentiation, but significantly (p < 0.05 vs. control animals) decreased the offspring weight on days 0-28 and the weight of their reproductive organs. Furthermore, lead exposure delayed the onset of puberty. These pathological changes were dose-dependently rectified or attenuated by selenium supplementation. Gestational lead exposure causes damages to the reproductive system of pregnant rats, and negatively modulates growth and reproductive system development of the offspring. These adverse effects are rectified or attenuated by selenium supplementation.

  11. Pediatric lead exposure from imported Indian spices and cultural powders.

    PubMed

    Lin, Cristiane Gurgel; Schaider, Laurel Anne; Brabander, Daniel Joseph; Woolf, Alan David

    2010-04-01

    Significant lead poisoning has been associated with imported nonpaint products. To describe cases of pediatric lead intoxication from imported Indian spices and cultural powders, determine lead concentrations in these products, and predict effects of ingestion on pediatric blood lead levels (BLLs). Cases and case-study information were obtained from patients followed by the Pediatric Environmental Health Center (Children's Hospital Boston). Imported spices (n = 86) and cultural powders (n = 71) were analyzed for lead by using x-ray fluorescence spectroscopy. The simple bioaccessibility extraction test was used to estimate oral bioavailability. The integrated exposure uptake biokinetic model for lead in children was used to predict population-wide geometric mean BLLs and the probability of elevated BLLs (>10 microg/dL). Four cases of pediatric lead poisoning from Indian spices or cultural powders are described. Twenty-two of 86 spices and foodstuff products contained >1 microg/g lead (for these 22 samples, mean: 2.6 microg/g [95% confidence interval: 1.9-3.3]; maximum: 7.6 microg/g). Forty-six of 71 cultural products contained >1 microg/g lead (for 43 of these samples, mean: 8.0 microg/g [95% confidence interval: 5.2-10.8]; maximum: 41.4 microg/g). Three sindoor products contained >47% lead. With a fixed ingestion of 5 microg/day and 50% bioavailability, predicted geometric mean BLLs for children aged 0 to 4 years increased from 3.2 to 4.1 microg/dL, and predicted prevalence of children with a BLL of >10 microg/dL increased more than threefold (0.8%-2.8%). Chronic exposure to spices and cultural powders may cause elevated BLLs. A majority of cultural products contained >1 microg/g lead, and some sindoor contained extremely high bioaccessible lead levels. Clinicians should routinely screen for exposure to these products.

  12. Environmental contamination and human exposure to lead in Brazil.

    PubMed

    Paoliello, Monica M B; De Capitani, Eduardo M

    2005-01-01

    Adverse effects caused by environmental lead pollution are well recognized. Being a widespread agent in the environment and a major harmful element to organic systems, mostly to children, lead has been investigated all over the world, aiming to improve measures regarding its control. The purpose of this chapter is to present a review of the situation of production, uses, assessment of exposure, and adverse effects from environmental lead contamination in Brazil. It also presents aspects of Brazilian legislation setting up maximum permissible levels of lead in several environmental compartments such as surface and drinking water, soils, sediment, urban air, and also in commercially sold food, vegetables, fish, and meat, in an effort to control industrial emissions. Epidemiological investigations on children's lead exposure around industrial and mining areas are revised, showing that many situations where lead contamination is potentially present still need to be addressed by governmental agencies. In Brazil, lead was withdrawn from gasoline by the end of the 1980s, and the last lead mining and primary smelting plant was closed in 1995, leaving residual environmental lead contamination, which has recently been investigated using a multidisciplinary approach. Nevertheless, there are hundreds of small secondary battery recycling plants all over the country, running smelting facilities that produce local urban areas of lead contamination.

  13. Assessment of soil lead exposure in children in Shenyang, China.

    PubMed

    Ren, H M; Wang, J D; Zhang, X L

    2006-11-01

    Soil lead pollution is serious in Shenyang, China. The paper brings together the soil work, the bioaccessibility, and the blood lead data to assess the soil lead exposure in children in Shenyang, China. Approximately 15.25% of the samples were above China Environment Protection Agency guideline concentration for soil Pb to protect human from health risk (350 mgkg(-1)). Pb concentrations varied among use scenarios. The main lead contamination sources are industry emission and automobile exhaust. Bioaccessibility also varied among use scenarios. Children, who ingested soil from industrial area, public parks, kindergarten playground, and commercial area, are more susceptible to soil lead toxicity. The industrial area soil samples presented higher bioaccessibility compared to the other use scenario soil samples contaminated by automobile exhaust. The result also suggested a most significant linear relationship between the level of Pb contamination and the amount of Pb mobilized from soil into ingestion juice. Soil pH seemed to have insignificant influence on bioaccessibility in the present study. Bioaccessibility was mainly controlled by other factors that are not investigated in this study. A linear relationship between children blood lead and soil intestinal bioaccessibility was present in the study. Children who are 4-5 years old are more likely to demonstrate the significant relationship between soil lead bioaccessibility and blood lead as their behaviors place them at greatest risk of soil lead toxicity, and their blood lead levels are more likely to represent recent exposure.

  14. OSHA lead in construction compliance directive: Exposure assessment

    SciTech Connect

    Vernon, L.S.

    1994-07-01

    This article is the second in a series that reviews the Occupational Health and Safety Administration (OSHA) Instruction CPL 2-2.58, a compliance directive for 29 CFR 1926.62, Lead Exposure in Construction. The OSHA document is intended to provide guidance to those charged with field enforcement of the lead regulation; however, it also provides vital information to those in industry who must comply with the regulation. This month, the requirements for compliance with 29 CFR 1926.62 (d) Exposure Assessment are discussed.

  15. Environmental and biological monitoring for lead exposure in California workplaces.

    PubMed Central

    Rudolph, L; Sharp, D S; Samuels, S; Perkins, C; Rosenberg, J

    1990-01-01

    Patterns of environmental and biological monitoring for lead exposure were surveyed in lead-using industries in California. Employer self-reporting indicates a large proportion of potentially lead-exposed workers have never participated in a monitoring program. Only 2.6 percent of facilities have done environmental monitoring for lead, and only 1.4 percent have routine biological monitoring programs. Monitoring practices vary by size of facility, with higher proportions in industries in which larger facilities predominate. Almost 80 percent of battery manufacturing employees work in job classifications which have been monitored, versus only 1 percent of radiator-repair workers. These findings suggest that laboratory-based surveillance for occupational lead poisoning may seriously underestimate the true number of lead poisoned workers and raise serious questions regarding compliance with key elements of the OSHA Lead Standard. PMID:2368850

  16. Neonatal lead exposure impairs development of rodent barrel field cortex

    PubMed Central

    Wilson, Mary Ann; Johnston, Michael V.; Goldstein, Gary W.; Blue, Mary E.

    2000-01-01

    Childhood exposure to low-level lead can permanently reduce intelligence, but the neurobiologic mechanism for this effect is unknown. We examined the impact of lead exposure on the development of cortical columns, using the rodent barrel field as a model. In all areas of mammalian neocortex, cortical columns constitute a fundamental structural unit subserving information processing. Barrel field cortex contains columnar processing units with distinct clusters of layer IV neurons that receive sensory input from individual whiskers. In this study, rat pups were exposed to 0, 0.2, 1, 1.5, or 2 g/liter lead acetate in their dam's drinking water from birth through postnatal day 10. This treatment, which coincides with the development of segregated columns in the barrel field, produced blood lead concentrations from 1 to 31 μg/dl. On postnatal day 10, the area of the barrel field and of individual barrels was measured. A dose-related reduction in barrel field area was observed (Pearson correlation = −0.740; P < 0.001); mean barrel field area in the highest exposure group was decreased 12% versus controls. Individual barrels in the physiologically more active caudoventral group were affected preferentially. Total cortical area measured in the same sections was not altered significantly by lead exposure. These data support the hypothesis that lead exposure may impair the development of columnar processing units in immature neocortex. We demonstrate that low levels of blood lead, in the range seen in many impoverished inner-city children, cause structural alterations in a neocortical somatosensory map. PMID:10805810

  17. Chronic lead exposure in children living in Miskolc Hungary, on the basis of teeth lead levels

    SciTech Connect

    Selypes, A.; Banfalvi, S.; Bokros, F.

    1997-03-01

    The lead pollution of the environment is a global problem. The major part of lead pollution can derive from the traffic, from exhausted gases of vehicles. Adverse health effects of lead exposure in childhood are well documented. Blood lead (Pb) levels are indicis of absorption during the previous 21- 30 days, whereas measurements of Pb in bone and in teeth reflect cumulative lead exposure. On the basis of that knowledge, we wanted to determine the tooth lead levels of children living in Miskolc, Hungary. The city of Miskolc is situated on the North-East part of Hungary, and can be characterized by urban-industrial air pollution. The population of the city is about 200,000. 10 refs., 1 fig., 3 tabs.

  18. Neurotoxic Effects and Biomarkers of Lead Exposure: A Review

    PubMed Central

    Sanders, Talia; Liu, Yiming; Buchner, Virginia; Tchounwou, Paul B.

    2010-01-01

    Biological monitoring techniques are useful for risk assessment of toxic agents in the field of environmental health. Lead, a systemic toxicant affecting virtually every organ system, primarily affects the central nervous system, particularly the developing brain. Consequently, children are at a greater risk than adults of suffering from the neurotoxic effects of lead. The ability of lead to pass through the blood-brain barrier is due in large part to its ability to substitute for calcium ions. Within the brain, lead-induced damage in the prefrontal cerebral cortex, hippocampus, and cerebellum can lead to a variety of neurological disorders, such as brain damage, mental retardation, behavioral problems, nerve damage, and possibly Alzheimer’s disease, Parkinson’s disease, and schizophrenia. At the molecular level, lead interferes with the regulatory action of calcium on cell functions and disrupts many intracellular biological activities. Experimental studies have also shown that lead exposure may have genotoxic effects, especially in the brain, bone marrow, liver, and lung cells. This paper presents an overview of biomarkers of lead exposure and discusses the neurotoxic effects of lead with regard to children, adults, and experimental animals, updated to January 2009. PMID:19476290

  19. Influence of social factors on lead exposure and child development.

    PubMed Central

    Bornschein, R L

    1985-01-01

    A brief overview of current views of child development is provided, with particular attention given to the role the child's physical and social environment plays in influencing the developmental process. Examples from the recent literature are used to illustrate how these factors can influence lead exposure and most importantly how they might interact with lead to ameliorate or exacerbate possible lead effects. An example is provided which demonstrates that failure to control adequately and to adjust the data statistically to correct for the influence of these factors can lead one erroneously to attribute cognitive and behavioral changes to lead. Finally, data from the Cincinnati Prospective Lead Study are presented to illustrate the application of structural equation modeling as a means for unraveling the complex web of sociodemographic, environmental and behavioral influences on childhood lead exposure. The latter analysis indicates that for children less than 24 months of age, lead-containing dust in the home and on the children's hands are important determinates of their blood lead levels. This relationship is influenced by the amount of maternal involvement with their child and other indices of interaction between the child and primary caregiver. PMID:2417831

  20. Lead exposure and behavioral changes: comparisons of four occupational groups with different levels of lead absorption.

    PubMed

    Valciukas, J A; Lilis, R; Singer, R; Fischbein, A; Anderson, H A; Glickman, L

    1980-01-01

    The association between lead absorption and objective psychological performance tests in five groups with different levels of lead absorption was studied in the following groups: (1) a control, non-lead-exposed group; (2) cable splicers, (3) cable manufactures, and (4) secondary lead smelter workers. The following performance tests were used: Block Design, Digit Symbol, and Embedded Figures. Age-corrected performance test scores and the average of three test scores (INDEX) were used throughout. A significant association between performance tests scores and increased lead absorption was found. Zinc protoporphyrin level was a more "powerful" (in the statistical sense) indicator of lead-induced CNS effects than blood lead levels. This study provides additional evidence that neurotoxic effects associated with occupational exposure to lead can be demonstrated by means of performance tests. It has been known and widely accepted that increased lead absorption is associated with "non-specific" subjective symptoms: tiredness, sleep disturbance, irritability, etc. Psychometric techniques (including an appropriate statistical analysis strategy) are highly sensitive for the early detection of CNS neurotoxicity, such as metal toxicity. Moreover, even in lead-exposed but asymptomatic individuals, a significant correlation (negative) between test scores and levels of lead absorption could be detected. It is concluded that workers exposed to lead at levels considered "safe" might be at risk of developing brain dysfunction with long term exposure.

  1. Lead

    MedlinePlus

    ... EPA United States Environmental Protection Agency Search Search Lead Contact Us Share Lead Poisoning is Preventable If your home was built ... to protect people from harmful lead exposures. Less Lead in Drinking Water = Better Health Learn about the ...

  2. Hypertension`s lead connection: Does low-level exposure to lead cause high blood pressure?

    SciTech Connect

    Fackelmann, K.

    1996-06-15

    {open_quotes}Paying for the sins of the past.{close_quotes} is how researcher Howard Hu describes a proposed disease process in which lead stored for decades in the skeleton puts people at risk of high blood pressure. Previous research has linked this silvery white, poisonous metal to a host of ill effects in children, including learning disabilities, behavior problems, and brain damage. Now, Hu`s study indicates that past exposure may be causing today`s high blood pressure. If he`s right, the public health impact would be significant. {open_quotes}Tens of millions of Americans have been exposed over the years to lead,{close_quotes} says Philip J. Landrigan of Mount Sinai Medical Center in New York. {open_quotes}Adults today grew up at a time when we were still putting several hundred thousand tons of lead into gasoline each year.{close_quotes} Indeed, the men who developed high blood pressure during the recent study had in their bones lead concentrations, or lead burdens, that came from decades of everyday exposure. Such exposures resulted principally from breathing in fumes from leaded gasoline, drinking tap water from lead pipes or pipes soldered with lead, and inhaling or ingesting lead-laced paint dust or chips. This article goes on to discuss other studies and questions which still need to be answered.

  3. Developmental lead exposure has mixed effects on butterfly cognitive processes.

    PubMed

    Philips, Kinsey H; Kobiela, Megan E; Snell-Rood, Emilie C

    2017-01-01

    While the effects of lead pollution have been well studied in vertebrates, it is unclear to what extent lead may negatively affect insect cognition. Lead pollution in soils can elevate lead in plant tissues, suggesting it could negatively affect neural development of insect herbivores. We used the cabbage white butterfly (Pieris rapae) as a model system to study the effect of lead pollution on insect cognitive processes, which play an important role in how insects locate and handle resources. Cabbage white butterfly larvae were reared on a 4-ppm lead diet, a concentration representative of vegetation in polluted sites; we measured eye size and performance on a foraging assay in adults. Relative to controls, lead-reared butterflies did not differ in time or ability to search for a food reward associated with a less preferred color. Indeed, lead-treated butterflies were more likely to participate in the behavioral assay itself. Lead exposure did not negatively affect survival or body size, and it actually sped up development time. The effects of lead on relative eye size varied with sex: lead tended to reduce eye size in males, but increase eye size in females. These results suggest that low levels of lead pollution may have mixed effects on butterfly vision, but only minimal impacts on performance in foraging tasks, although follow-up work is needed to test whether this result is specific to cabbage whites, which are often associated with disturbed areas.

  4. Antibiotic impregnated catheter coverage of deep brain stimulation leads facilitates lead preservation after hardware infection.

    PubMed

    Dlouhy, Brian J; Reddy, Ambur; Dahdaleh, Nader S; Greenlee, Jeremy D W

    2012-10-01

    Deep brain stimulation (DBS) has become a reliable and effective treatment for many disorders. However, the risk of long-term hardware-related complications is notable, and most concerning is hardware-related infections. Given the risk of hardware removal in the setting of infection, we retrospectively examined the implementation of a novel technique using antibiotic covered catheter protection of DBS leads after infection. The effect on hardware salvage and ease of reimplantation of the DBS extension and implantable pulse generator (IPG) was examined. A total of nine (9%) out of 100 DBS patients met the inclusion criteria with 11 DBS hardware-related infections at either the frontal, parietal, or IPG sites, from June 2003 to November 2010, at our institution. Subsequent to the initial patient in the series, a total of eight patients had placement of a short segment (approx. 4 cm long) of antibiotic impregnated catheter (Bactiseal, Codman, Johnson & Johnson, Raynham, MA, USA) over the distal end of the DBS leads at the parietal incision. Seven of these eight patients presented with pus and deep tissue infections around the hardware at either the frontal, parietal, or chest incisions. In seven of these eight patients (87.5%) we were able to protect and salvage their DBS leads without need for removal. In conclusion, this novel technique provides a simple reimplantation operation, with a decreased risk of DBS lead damage. It may improve the preservation of DBS leads when hardware infection occurs, is inexpensive, and confers no additional risks to patients. Copyright © 2012 Elsevier Ltd. All rights reserved.

  5. Cardiotoxicity and hypertension in rats after oral lead exposure.

    PubMed

    Lal, B; Murthy, R C; Anand, M; Chandra, S V; Kumar, R; Tripathi, O; Srimal, R C

    1991-01-01

    The rats were exposed to lead (0.25, 0.5 and 1.0 per cent lead acetate through drinking water) for 90 days to study its effect on some physiological and morphological parameters of the cardiovascular system. Blood lead levels increased in a dose dependent manner but heart tissue showed rise at only two higher doses in exposed animals. The two higher doses of lead resulted in an increased arterial blood pressure and calcium influx in atrial trabeculae and papillary muscles. No marked pathological or histochemical changes were observed in heart tissue excepting congestion and slightly reduced activity of succinic dehydrogenase in the highest dosed group. It was concluded that lead exposure through drinking water may produce increased arterial blood pressure and minor changes in the myocardium. Whether these changes are mediated through the effect of lead on the calcium transport needs further investigation.

  6. Public health. Childhood lead exposure in Wisconsin in 1990

    SciTech Connect

    Schirmer, J.; Anderson, H.; Peterson, D.E. )

    1991-01-01

    It will take the cooperation of many people to address the issue of lead poisoning. The recent death has dramatized the problem of high dose exposures. But a larger challenge is posed by the fact that most preschool children in Wisconsin are not screened for lead and as a result many asymptomatic children without signs of pica behavior will experience subtle neurological damage as a result of low to moderate elevations of lead in blood. Because many of these cases occur in children without recognized pica behavior, doctors need to expand screening, especially during well child visits, to identify children with elevated blood lead levels. Additionally, the public health community and property owners need to evaluate and control sources of lead. Major efforts are needed to address the lead hazards which now impair hundreds of Wisconsin children each year.

  7. CHRONIC DEVELOPMENTAL LEAD EXPOSURE REDUCES NEUROGENESIS IN ADULT HIPPOCAMPUS.

    EPA Science Inventory

    CHRONIC DEVELOPMENTAL LEAD EXPOSURE REDUCES NEUROGENESIS IN ADULT HIPPOCAMPUS. ME Gilbert1, ME Kelly2, S. Salant3, T Shafer1, J Goodman3 1Neurotoxicology Div, US EPA, RTP, NC, 27711, 2Children's Hospital, Philadelphia, PA, 19104, 3Helen Hayes Hospital, Haverstraw, NY, 10993.
    ...

  8. CHRONIC DEVELOPMENTAL LEAD EXPOSURE REDUCES NEUROGENESIS IN ADULT HIPPOCAMPUS.

    EPA Science Inventory

    CHRONIC DEVELOPMENTAL LEAD EXPOSURE REDUCES NEUROGENESIS IN ADULT HIPPOCAMPUS. ME Gilbert1, ME Kelly2, S. Salant3, T Shafer1, J Goodman3 1Neurotoxicology Div, US EPA, RTP, NC, 27711, 2Children's Hospital, Philadelphia, PA, 19104, 3Helen Hayes Hospital, Haverstraw, NY, 10993.
    ...

  9. Lead exposure and educational proficiency: moderate lead exposure and educational proficiency on end-of-grade examinations.

    PubMed

    Amato, Michael S; Moore, Colleen F; Magzamen, Sheryl; Imm, Pamela; Havlena, Jeffrey A; Anderson, Henry A; Kanarek, Marty S

    2012-10-01

    To investigate and quantify the impact of moderate lead exposure on students' ability to score at the "proficient" level on end-of-grade standardized tests. We compared the scores of 3757 fourth grade students from Milwaukee, Wisconsin, on the Wisconsin Knowledge and Concepts Exam (WKCE). The sample consisted of children with a blood lead test before age 3 years that was either unquantifiable at the time of testing (<5 μg/dL) or in the range of moderate exposure (10-19 μg/dL). After controlling for gender, poverty, English language learner status, race/ethnicity, school disciplinary actions, and attendance percentage, results showed a significant negative effect of moderate lead exposure on academic achievement for all 5 subtests of the WKCE. Test score deficits owing to lead exposure were equal to 22% of the interval between student categorization at the "proficient" or "basic" levels in Reading, and 42% of the interval in Mathematics. Children exposed to amounts of lead before age 3 years that are insufficient to trigger intervention under current policies in many states are nonetheless at a considerable educational disadvantage compared with their unexposed peers 7 to 8 years later. Exposed students are at greater risk of scoring below the proficient level, an outcome with serious negative consequences for both the student and the school. Copyright © 2012 Elsevier Inc. All rights reserved.

  10. Leaded crystal as a source of dietary lead: An exposure assessment

    SciTech Connect

    Shorten, C.V.; Glowacki, M.L.

    1995-12-31

    Lead is a potent systemic toxic with many environmental sources. It can enter the body through a number of pathways, the most significant is ingestion. While many investigators of lead ingestion have focused on paint and dust sources, the authors examined food contaminated with lead from crystal ware. The rates and amounts of lead leached into vinegar stored in leaded crystal cruets were measured over the course of a 42-day laboratory study. Replicate lead oxide (PbO, 24%) crystal cruets (N = 13) were filled with vinegar, and sample aliquots were periodically removed for analysis. Lead leaching rates were determined by fitting a two-stage, non-linear model to the data, and observed rate coefficients were 0.066 hr{sup {minus}1} and 0.0019{sup {minus}1} for the first and second stages of leaching, respectively (R{sup 2} = 0.9680). Average lead concentrations in the stored vinegar range from 118 {micro}g/L at 8 parameters (ingestion rate, exposure frequency and duration, body weight, and averaging time) was generated to characterize the realm of potential intake estimates. Lead concentrations were input using the fitted model. Results indicated that a worst case lead intake estimate from this source could be as high as 420 {micro}g/kg/yr for a child. Crystal ware can be considered to be a potentially significant dietary source of lead, and risk characterizations cannot ignore this potential avenue when combining risks across all exposure pathways.

  11. Low level exposures to lead and neurobehavioral development: the Sydney lead study

    SciTech Connect

    Cooney, G.H.; Bell, A.; McBride, W.; Carter, C.

    1988-01-01

    The Sydney lead study is a prospective five year study investigating the relationship between low level lead exposures and neurobehavioral development during the first five years of life. From an initial cohort of 318 children, 207 remained at the end of the fourth year. Average blood lead levels at 42 and 48 months were 10.6 ug/dL and 10.1 ug/dL respectively, with only a minority of the observations exceeding 15 ug/dL. The series of regression analyses reported in this paper support earlier findings from the study, that exposures to lead which give rise to the range of blood lead levels found in this cohort of children are not associated with cognitive or motor deficits in the preschool years.

  12. Effect of prenatal and neonatal exposure to lead on gonadotropin receptors and steroidogenesis in rat ovaries

    SciTech Connect

    Wiebe, J.P.; Barr, K.J.; Buckingham, K.D.

    1988-01-01

    Sprague-Dawley rats were treated with lead chloride (20 or 200 ppm) or sodium chloride (controls) in their drinking water, either prior to pregnancy or during pregnancy and lactation, and female offspring were examined at weaning (21 d) or at 150 d. Other female rats were treated from d 21 to 35. Tissue (blood, kidney, bone) lead levels, body, ovary, and uterus weights, ovarian steroidogenesis, and gonadotropin (luteinizing hormone and follicle-stimulating hormone) levels, and gonadotropin-receptor binding were determined. Prenatal and/or postnatal exposure to lead at these levels (20 and 200 ppm) did not affect tissue weights but did cause a significant decrease in gonadotropin-receptor binding in the prepubertal, pubertal and adult females. Conversion of progesterone to androstenedione and dihydrotestosterone was significantly decreased in 21-d-old rats; in 150-d-old females, the prenatal and/or postnatal exposure to lead resulted in significantly increased conversion to the 5-alpha-reduced steroid, normally high during puberty. The results demonstrate that lead exposure prior to mating may affect gonadotropin-receptor binding in the offspring and that lead exposure (in utero, via mother's milk, or post weaning) may significantly alter steroid production and gonadotropin binding in ovaries of the prepubertal, pubertal, and adult female.

  13. Anemia risk in relation to lead exposure in lead-related manufacturing.

    PubMed

    Hsieh, Nan-Hung; Chung, Shun-Hui; Chen, Szu-Chieh; Chen, Wei-Yu; Cheng, Yi-Hsien; Lin, Yi-Jun; You, Su-Han; Liao, Chung-Min

    2017-05-05

    Lead-exposed workers may suffer adverse health effects under the currently regulated blood lead (BPb) levels. However, a probabilistic assessment about lead exposure-associated anemia risk is lacking. The goal of this study was to examine the association between lead exposure and anemia risk among factory workers in Taiwan. We first collated BPb and indicators of hematopoietic function data via health examination records that included 533 male and 218 female lead-exposed workers between 2012 and 2014. We used benchmark dose (BMD) modeling to estimate the critical effect doses for detection of abnormal indicators. A risk-based probabilistic model was used to characterize the potential hazard of lead poisoning for job-specific workers by hazard index (HI). We applied Bayesian decision analysis to determine whether BMD could be implicated as a suitable BPb standard. Our results indicated that HI for total lead-exposed workers was 0.78 (95% confidence interval: 0.50-1.26) with risk occurrence probability of 11.1%. The abnormal risk of anemia indicators for male and female workers could be reduced, respectively, by 67-77% and 86-95% by adopting the suggested BPb standards of 25 and 15 μg/dL. We conclude that cumulative exposure to lead in the workplace was significantly associated with anemia risk. This study suggests that current BPb standard needs to be better understood for the application of lead-exposed population protection in different scenarios to provide a novel standard for health management. Low-level lead exposure risk is an occupational and public health problem that should be paid more attention.

  14. [Association between low blood lead exposure and nervous system symptoms].

    PubMed

    Dou, Qianru; Wang, Yan; Cai, Chang; Li, Jimeng; Tan, Hongzhuan

    2015-05-01

    To explore the association between low blood lead exposure and nervous system symptoms among the workers exposed to oil paint. Through cluster sampling, workers with occupational oil paint exposure in 2 factories were selected to conduct a questionnaire survey, biochemical detection and health examination. χ2 test and unconditional logistic regression analysis were performed for the determinants analysis. A total of 525 oil paint workers completed the survey, in whom, 55 (10.5%) were blood lead positive, the mean of blood lead concentration was (0.0884±0.0539) mg/L, 278 (52.95%) had nervous system like symptoms and 69 (13.14%) had peripheral neuropathy symptoms. Multinomial logistic regression analysis showed that working age (OR=1.827), drinking (OR=1.607), health status (OR=3.862), blood lead (OR=1.983) were risk factors for nervous system like symptoms. Working age (OR=2.282), and drinking (OR=2.704) were risk factors for peripheral neuropathy. Low blood lead exposure might be associated with nervous system like symptoms.

  15. Behavioral effects of low level neonatal lead exposure.

    PubMed

    Hastings, L; Cooper, G P; Bornschein, R L; Michaelson, I A

    1977-07-01

    Rats exposed to lead via maternal milk were tested at various stages of development on a number of behavioral tasks. Beginning at paturition, the dams were given either tap water, 0.02%, or 0.10% lead acetate in the drinking water. Pups from all three groups were weaned to normal chow and tap water at 21 days of age. The mean lead concentration of the dam's blood and of neonatal (20 days of age) brain and blood were all below 50 microgram/100 ml. No significant differences were found between the high lead-exposed group and controls in general as measured by wheel running over a 21 day period beginning at 30 days of age. However, there was a significant difference in wheel running behavior during the first three hr of testing. Both lead-exposed groups were found to display significantly less aggressive behavior as measured by the shock-elicited aggression test. Low level lead exposure had no discernable effect on the acquisition and subsequent reversal of a successive brightness discrimination task. Lead exposure under these conditions appears to affect some aspects of emotional behavior, while having little effect on general activity or cognitive function.

  16. Environmental and Occupational Lead Exposure Among Children in Cairo, Egypt

    PubMed Central

    Moawad, Eman Mohamed Ibraheim; Badawy, Nashwa Mostafa; Manawill, Marie

    2016-01-01

    Abstract The aim of this study was to assess childhood lead exposure in a representative sample of Cairo, and to investigate the possible risk factors and sources of exposure. This cross-sectional study was conducted from November 2014 through April 2015. The target population was children aged 6 to 18 years, recruited into 4 groups, garbage city, moderate-living standard area, urban and suburban schools, and workshops in the city of Cairo. Blood lead levels (BLLs) and hemoglobin (Hb) concentrations were measured. Also, potential local environmental sources were assessed for hazardous lead contamination. Analysis on 400 participants has been carried out. A total of 113 children had BLLs in the range 10 to 20 μg/dL. Smoking fathers, housing conditions, playing outdoors, and exposure to lead in residential areas were significantly correlated with high BLLs. The mean values of hemoglobin were inversely correlated with BLLs. Children involved in pottery workshops had the highest BLLs and the lowest Hb values with a mean of (43.3 μg/dL and 8.6 g/dL, respectively). The mean value of environmental lead in workshop areas exceeded the recommended levels. Also, those values measured in dust and paint samples of garbage city were significantly high. Moreover, the mean lead levels in the soil samples were significantly higher in urban schools (P = 0.03) than the suburban ones. Childhood lead poisoning accounts for a substantial burden in Egypt, which could be preventable. Development of national prevention programs including universal screening program should be designed to reduce incidence of lead toxicity among children. PMID:26945415

  17. Occupational exposure to lead: effects on renal function

    SciTech Connect

    Hong, C.D.; Hanenson, I.B.; Lerner, S.; Hammond, P.B.; Pesce, A.J.; Pollak, V.E.

    1980-10-01

    Although nephrotoxicity is common following exposure to lead, the dose-response relationship in adults with occupational exposure is not well understood because information is lacking on early nephrotoxic effects. By the time serum urea nitrogen and creatinine levels are elevated, renal damage may be advanced and not fully reversible. Detailed investigations of renal glomerular and tubular function were performed in six adults with occupational exposure to lead. In all patients, the serum creatinine and urea nitrogen concentrations were within the normal range. GFR was decreased in all but two. Glucose reabsorptive capacity (TmG) was decreased in all, and this decrease was disproportionately greater than expected from the reduced GFR in all but one. Normal values for renal plasma flow (RFP) were observed in four of the six, and for rho-aminohippurate (PAH) secretory capacity (TmPAh) in all but one. Bicarbonate reabsorptive capacity (TmHCO3) and urinary excretion of beta2-microglobulin were normal in all. Routine clinical laboratory tests are insensitive for the detection of early renal effects of heavy metal exposure. Measurements of renal tubular reabsorptive capacity for glucose appears to be a sensitive method for the early detection of renal effect of lead.

  18. [Lead exposure in pregnant women and newborns: a screening update].

    PubMed

    Yazbeck, C; Cheymol, J; Dandres, A-M; Barbéry-Courcoux, A-L

    2007-01-01

    Human lead exposure has many sources. Relative importance of these sources varies widely according to geographic regions and human lifestyle. The impact of lead exposure on health has been well studied and public health interventions have been conducted. The aim of this study was to evaluate current prevalence of lead burden in neonates, and seek for sources of maternal and fetal intoxication. A prospective multicentre study was conducted by the "Réseau périnatal 92" on a population of pregnant women attending 3 maternal wards in the north of 'Hauts-de-Seine' department in France. Between December 2003 and May 2004, a total of 1021 pregnant women were included. All patients signed an informed consent before participating in the study. Cord blood samples were collected at delivery for lead measurements. The mean cord blood lead concentration was 23.2 microg/l. Eighteen neonates over 1021 (1.8%) had lead levels above 100 microg/l. An environmental query was conducted by the social and public health office of the department (DDASS), and data were collected regarding the state of the housing and the lifestyle of the concerned family. Main sources of lead intoxication were 'tagine' food plates in 83.3% of cases, 'khôl' powder (used as eyeliner) in 88.9% of cases and substandard housings in 22.2% of cases. A specialized paediatric follow-up for the 18 neonates was performed. With the exception of substandard housing (old lead painting), other sources of lead intoxication were discovered: 'tagine' plates and 'khôl' powder. Almost all of these products came from Morocco. A public health intervention would be able to inform the population about these yet unknown sources of lead intoxication.

  19. Influence of the degree of exposure to lead on relations between alcohol consumption and the biological indices of lead exposure: epidemiological study in a lead acid battery factory.

    PubMed Central

    Cezard, C; Demarquilly, C; Boniface, M; Haguenoer, J M

    1992-01-01

    Alcohol has been shown to interact with lead to influence haem biosynthesis. The aim of this study was to define the dependence of this interaction on the degree of exposure to lead. Exposure to alcohol was estimated by measurement of alcohol concentrations in a sample of urine collected during the morning (AlcUM) (0.82 (SD 4.36) mmol/l) and in a sample collected during the afternoon (AlcUA) (1.15 (SD 3.49) mmol/l). The biological monitoring of exposure to lead included measurements of blood lead (Pb-B) (1.82 (SD 0.72) mumol/l), urinary delta-aminolaevulinic acid (ALAU) (35.33 (SD 28.00) mumol/l; d = 1.015), and erythrocyte zinc-protoporphyrin (ZPP) (112.90 (SD 83.71) nmol/mmol Hb) concentrations. The study of the influence of the degree of occupational exposure to lead on relations between alcohol consumption and effects of the exposure to lead led to the consideration of two different groups--namely, mildly and strongly exposed subjects. In the first group, individual biological susceptibility seemed to play a preponderant part. In the second, the pool of lead present in the body seemed to be sufficiently important to mask the effects of individual susceptibility. PMID:1390270

  20. Primary Prevention of Lead Exposure: The Philadelphia Lead Safe Homes Study

    PubMed Central

    Campbell, Carla; Tran, Mary; Gracely, Edward; Starkey, Naomi; Kersten, Hans; Palermo, Peter; Rothman, Nancy; Line, Laura; Hansen-Turton, Tine

    2011-01-01

    Objective Lead exposure in children can lead to neuropsychological impairment. This study tested whether primary prevention interventions in the newborn period prevent elevated blood lead levels (BLLs). Methods The Philadelphia Lead Safe Homes (LSH) Study offered parental education, home evaluation, and lead remediation to the families of urban newborns. Households were randomized to a standard lead education group or maintenance education group. We conducted home visits at baseline, six months, and 12 months. To compare BLLs, we identified a matched comparison group. Results We enrolled and randomized 314 newborns in the intervention component; 110 completed the study. There were few significant differences between the randomized groups. In the combined intervention groups, positive results on visual inspection declined from baseline to 12 months (97.0% to 90.6%, p=0.007). At baseline, 36.9% of homes were above the U.S. Environmental Protection Agency's lead dust standard, compared with 26.9% at 12 months (p=0.032), mainly due to a drop in windowsill dust levels. Both groups showed a significant increase in parental scores on a lead education test. Children in the intervention and matched control groups had similar geometric mean initial BLLs (2.6 vs. 2.7, p=0.477), but a significantly higher percentage of children in the intervention group had an initial blood lead screening compared with those in the matched group (88.9% vs. 84.4%, p=0.032). Conclusions A study of primary prevention of lead exposure showed a higher blood lead screening rate for the combined intervention groups and mean BLLs at one year of age not statistically different from the comparison group. Most homes had lead hazards. Lead education significantly increased knowledge. PMID:21563715

  1. Protoporphyrin (FEP/ZPP) screening in industrial lead exposure

    SciTech Connect

    Saryan, L.A.

    1988-11-01

    Lead-acid battery manufacturers, as a group, are among the largest industrial users of lead in the United States, and every industry using this metal is confronted with a maze of federal regulations governing workplace conditions and employee health. In the biological testing category, particular emphasis has been placed on the periodic testing of blood for lead, to assess absorption of the metal, and protoporphyrin (abbreviated ZPP or FEP) testing as a means of monitoring the biological effects resulting from lead exposure. The protoporphyrin test, however, remains a matter of general confusion among industry managers and medical directors, and this article attempts to provide a concise and understandable explanation of this topic. 10 references, 3 figures, 1 table.

  2. Peripheral blood findings associated with asymptomatic lead exposure

    SciTech Connect

    Day, C.M.; Tennant, F.S. Jr.

    1982-02-01

    This study was done to determine whether erythroid alterations can be found on a peripheral blood smear from an asymptomatic person exposure to excess atmospheric lead. Thirty healthy, asymptomatic adults who lived within five miles of a major Los Angeles, California freeway for five consecutive years were studied. Erythroid cytologic alterations-including-anisocytosis, poikilocytosis, polychromasia and basophilic stippling were statistically associated with increased free erythrocyte protoporphyrin levels. These findings indicate that erythroid alterations may be found on a peripheral blood smear prior to the development of clinical symptoms of lead intoxication.

  3. Exposure to lead in South African shooting ranges.

    PubMed

    Mathee, Angela; de Jager, Pieter; Naidoo, Shan; Naicker, Nisha

    2017-02-01

    Lead exposure in shooting ranges has been under scrutiny for decades, but no information in this regard is available in respect of African settings, and in South Africa specifically. The aim of this study was to determine the blood lead levels in the users of randomly selected private shooting ranges in South Africa's Gauteng province. An analytical cross sectional study was conducted, with participants recruited from four randomly selected shooting ranges and three archery ranges as a comparator group. A total of 118 (87 shooters and 31 archers) were included in the analysis. Shooters had significantly higher blood lead levels (BLL) compared to archers with 36/85 (42.4%) of shooters versus 2/34 (5.9%) of archers found to have a BLL ≥10μg/dl (p<0.001). Shooting ranges may constitute an import site of elevated exposure to lead. Improved ventilation, low levels of awareness of lead hazards, poor housekeeping, and inadequate personal hygiene facilities and practices at South African shooting ranges need urgent attention. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  4. Elevated blood lead levels from exposure via a radiator workshop.

    PubMed

    Treble, R G; Thompson, T S; Morton, D N

    1998-04-01

    Elevated lead levels were discovered in blood samples collected from family members where both the father and the mother worked in a radiator repair workshop. The father and mother were found to have blood lead levels of 2.0 and 0.5 mumol/L (41.7 and 10.4 micrograms/dL), respectively. The father's blood lead level was just below the Canadian occupational health and safety intervention level (2.5 mumol/L or 52.1 micrograms/dL). The two children had blood lead levels of 1.0 and 0.8 mumol/L (20.8 and 16.7 micrograms/dL), both of which are in excess of the recommended guideline for intervention in the case of children (0.5 mumol/L or 10.4 micrograms/dL). The exposure of the two children was possibly due to a combination of pathways including exposure at the workshop itself during visits and also the transportation of lead-containing dust to the home environment.

  5. Early (in uterus and infant) exposure to mercury and lead.

    PubMed

    Dorea, Jose G; Donangelo, Carmen M

    2006-06-01

    Mercury and lead are toxic metals widely spread in the environment with bio-accumulative features that raises public health concerns. Both metals are equally dispersed in the human food chain but exposure and risk of toxicity during early human development are modulated by the diet and nutritional status. Understanding how Hg and Pb occur and interact with nutrients is fundamental to establish guidelines for diminishing exposure and the risk of toxicity. The risk of fetal and infant exposure to Hg can be influenced by maternal amalgam filling (inorganic Hg) and fish consumption (monomethyl Hg), whereas the risk of exposure to Pb is complex: maternal absorption depends on nutrient interactions (Ca and P); and maternal body Pb accumulation responds to all factors known to interact with bone and calcium metabolism. Maternal exposure to Hg and Pb is more important during fetal development than during breastfeeding. Moreover, these metals (especially Pb) are frequently higher in infant formulas which do not carry the nutritional and psychological advantages and protection of breastfeeding. Infant's reference dose is lower for Hg than for Pb, but risk of Pb contamination for fetuses and infant (breast- or formula-fed) is higher and lasts longer than Hg. Breastfeeding is essential to complete infant development. Interruption or suppression of breast-feeding with cow's milk-based formulas is not an option to environmental pollution.

  6. Methods for integrated exposure monitoring of lead and cadmium

    SciTech Connect

    Vahter, M.; Berglund, M.; Friberg, L. ); Slorach, S. ); Saric, M. ); Zheng Xingquan ); Fujita, Masahiko )

    1991-10-01

    An international pilot monitoring study on exposure to lead (Pb) and cadmium (Cd) has been implemented in Beijing, Yokohama, Stockholm, and Zagreb as part of the UNEP/WHO human exposure assessment locations (HEAL) Program. The main objective was to develop and test methods, including methods for quality assurance, for monitoring of personal exposure to Pb and Cd. The study included analytical training for Pb and Cd in blood, air filters, dust, diets, and feces, as well as exposure monitoring activities in small groups of nonsmoking women, 23-53 years of age, during 7 consecutive days. Airborne particulates, duplicate diets, feces, and blood were collected. An extensive quality assurance program was implemented in order to assure the reliability and comparability of the monitoring data. The main problem in the sample collection was associated with the air monitoring. The pumps were noisy, and the batteries had to be recharged every 6-8 hr. Collection of duplicate diets during 1 week gave good estimates of average dietary intakes of Pb and Cd. The metal contents in feces were found useful for evaluation of total peroral intakes. The methods used made it possible to demonstrate that the diet was the main source of Cd exposure at all the HEAL sites.

  7. Prevalence of elevated blood leads and exposure to lead in construction trades in Iowa and Illinois.

    PubMed

    Reynolds, S J; Seem, R; Fourtes, L J; Sprince, N L; Johnson, J; Walkner, L; Clarke, W; Whitten, P

    1999-08-01

    Despite lowering of the permissible exposure level for lead in construction from 200 to 50 microg/m3 in 1993, excessive lead exposure continues to be a problem. Relatively little data are available from the Midwestern U.S. on the environmental lead concentrations generated during various construction activities and the potential for worker exposure. This study characterized the prevalence of blood lead concentrations in high-risk construction trades in Iowa/Illinois, and identified risk factors for occupational exposure to lead in these construction workers. A sample of 459 workers was selected from the total population of all union members from trade groups of painters, plumbers/pipefitters, ironworkers, laborers, and electricians. Participants completed an interviewer-administered questionnaire obtaining information on demographics, symptoms, occupational history, work practices, personal protective equipment, and training. Venous blood samples were collected from each participant and analyzed for blood lead (using atomic absorption spectroscopy) and free erythrocyte protoporphyrin levels. Blood lead levels (BLLs) of construction workers ranged from 0.1 to 50 microg/dL. Geometric mean blood lead concentrations by trade group were: laborers (7.6 microg/dL, n = 80); painters (5.9 microg/dL, n = 83); ironworkers (5.2 microg/dL, n = 87); plumbers (4.4 microg/dL, n = 82); electricians (2.4 microg/dL, n = 91). Blood lead levels for painters and laborers were significantly higher than other trade groups, and levels for electricians were significantly lower (p < 0. 01). Participants reported working primarily on commercial and industrial projects including new construction, renovation, and demolition. There were significant differences between the types of projects performed by different trade groups with laborers performing more highway/bridge renovation (p < 0.01), and plumbers reporting more residential remodeling (p = 0.05), repair of water lines containing lead (p

  8. Reproductive toxicity of low-level lead exposure in men

    SciTech Connect

    Telisman, Spomenka Colak, Bozo; Pizent, Alica; Jurasovic, Jasna; Cvitkovic, Petar

    2007-10-15

    Parameters of semen quality, seminal plasma indicators of secretory function of the prostate and seminal vesicles, sex hormones in serum, and biomarkers of lead, cadmium, copper, zinc, and selenium body burden were measured in 240 Croatian men 19-52 years of age. The subjects had no occupational exposure to metals and no known other reasons suspected of influencing male reproductive function or metal metabolism. After adjusting for age, smoking, alcohol, blood cadmium, and serum copper, zinc, and selenium by multiple regression, significant (P<0.05) associations of blood lead (BPb), {delta}-aminolevulinic acid dehydratase (ALAD), and/or erythrocyte protoporphyrin (EP) with reproductive parameters indicated a lead-related increase in immature sperm concentration, in percentages of pathologic sperm, wide sperm, round sperm, and short sperm, in serum levels of testosterone and estradiol, and a decrease in seminal plasma zinc and in serum prolactin. These reproductive effects were observed at low-level lead exposure (BPb median 49 {mu}g/L, range 11-149 {mu}g/L in the 240 subjects) common for general populations worldwide. The observed significant synergistic effect of BPb and blood cadmium on increasing serum testosterone, and additive effect of a decrease in serum selenium on increasing serum testosterone, may have implications on the initiation and development of prostate cancer because testosterone augments the progress of prostate cancer in its early stages.

  9. A novel lead design enables selective deep brain stimulation of neural populations in the subthalamic region

    NASA Astrophysics Data System (ADS)

    van Dijk, Kees J.; Verhagen, Rens; Chaturvedi, Ashutosh; McIntyre, Cameron C.; Bour, Lo J.; Heida, Ciska; Veltink, Peter H.

    2015-08-01

    Objective. The clinical effects of deep brain stimulation (DBS) of the subthalamic nucleus (STN-DBS) as a treatment for Parkinson’s disease are sensitive to the location of the DBS lead within the STN. New high density (HD) lead designs have been created which are hypothesized to provide additional degrees of freedom in shaping the stimulating electric field. The objective of this study is to compare the performances of a new HD lead with a conventional cylindrical contact (CC) lead. Approach. A computational model, consisting of a finite element electric field model combined with multi-compartment neuron and axon models representing different neural populations in the subthalamic region, was used to evaluate the two leads. We compared ring-mode and steering-mode stimulation with the HD lead to single contact stimulation with the CC lead. These stimulation modes were tested for the lead: (1) positioned in the centroid of the STN, (2) shifted 1 mm towards the internal capsule (IC), and (3) shifted 2 mm towards the IC. Under these conditions, we quantified the number of STN neurons that were activated without activating IC fibers, which are known to cause side-effects. Main results. The modeling results show that the HD lead is able to mimic the stimulation effect of the CC lead. Additionally, in steering-mode stimulation there was a significant increase of activated STN neurons compared to the CC mode. Significance. From the model simulations we conclude that the HD lead in steering-mode with optimized stimulation parameter selection can stimulate more STN cells. Next, the clinical impact of the increased number of activated STN cells should be tested and balanced across the increased complexity of identifying the optimized stimulation parameter settings for the HD lead.

  10. A novel lead design enables selective deep brain stimulation of neural populations in the subthalamic region.

    PubMed

    van Dijk, Kees J; Verhagen, Rens; Chaturvedi, Ashutosh; McIntyre, Cameron C; Bour, Lo J; Heida, Ciska; Veltink, Peter H

    2015-08-01

    The clinical effects of deep brain stimulation (DBS) of the subthalamic nucleus (STN-DBS) as a treatment for Parkinson's disease are sensitive to the location of the DBS lead within the STN. New high density (HD) lead designs have been created which are hypothesized to provide additional degrees of freedom in shaping the stimulating electric field. The objective of this study is to compare the performances of a new HD lead with a conventional cylindrical contact (CC) lead. A computational model, consisting of a finite element electric field model combined with multi-compartment neuron and axon models representing different neural populations in the subthalamic region, was used to evaluate the two leads. We compared ring-mode and steering-mode stimulation with the HD lead to single contact stimulation with the CC lead. These stimulation modes were tested for the lead: (1) positioned in the centroid of the STN, (2) shifted 1 mm towards the internal capsule (IC), and (3) shifted 2 mm towards the IC. Under these conditions, we quantified the number of STN neurons that were activated without activating IC fibers, which are known to cause side-effects. The modeling results show that the HD lead is able to mimic the stimulation effect of the CC lead. Additionally, in steering-mode stimulation there was a significant increase of activated STN neurons compared to the CC mode. From the model simulations we conclude that the HD lead in steering-mode with optimized stimulation parameter selection can stimulate more STN cells. Next, the clinical impact of the increased number of activated STN cells should be tested and balanced across the increased complexity of identifying the optimized stimulation parameter settings for the HD lead.

  11. Environmental lead exposure as a risk for childhood aplastic anemia.

    PubMed

    Ahamed, M; Akhtar, M J; Verma, S; Kumar, A; Siddiqui, M K J

    2011-01-01

    Concern about environmental lead exposure as a significant public health threat has increased as evidence has accumulated regarding adverse health effects at successively lower levels. Aplastic anemia is a hematological disorder of unknown etiology with a high lethality rate. Lead is a known toxicant for the hematopoietic system. Oxidative stress appears to be the possible mode of lead toxicity. We evaluated the effects of blood lead level on oxidative stress parameters in children suffering from aplastic anemia disease. Seventeen children with aplastic anemia disease (15 male and 2 female, age 3-12 y) were recruited in the study group. Fifty one healthy children (45 male and 6 female, age 3-12 y) having normal blood profiles and not suffering from any chronic disease(s) were used as controls. Blood lead level and oxidative stress parameters were determined. Mean blood lead level was significantly higher while δ-aminolevulinic acid dehydratase (δ-ALAD) activity, a biomarker for lead exposure was significantly lower in the study group as compared to the control group (p < 0.05 for each). Thiobarbituric acid reactive species (TBARS), a marker of lipid peroxidation, was significantly higher while the antioxidant glutathione (GSH) level was significantly lower in the study group as compared to the control group (p < 0.05 for each). Activity of the antioxidant enzyme catalase (CAT) was significantly higher in the study group than in the control group (p < 0.05). There was a significant negative correlation of blood lead levels with δ-ALAD (r = -0.45; p < 0.05) and GSH (r = -0.32; p < 0.05), and a positive correlation with TBARS (r = 0.41; p < 0.05) and CAT (r = 0.37; p < 0.05). Although a causal pathway cannot be determined from this study, our results indicated that lead induces oxidative stress in children suffering from aplastic anemia. Lead-induced oxidative stress as an underlying mechanism for aplastic anemia warrants further research.

  12. Modeling the impact of spinal cord stimulation paddle lead position on impedance, stimulation threshold, and activation region.

    PubMed

    Xiaoyi Min; Kent, Alexander R

    2015-08-01

    The effectiveness of spinal cord stimulation (SCS) for chronic pain treatment depends on selection of appropriate stimulation settings, which can be especially challenging following posture change or SCS lead migration. The objective of this work was to investigate the feasibility of using SCS lead impedance for determining the location of a SCS lead and for detecting lead migration, as well as the impact of axial movement and rotation of the St. Jude Medical PENTA™ paddle in the dorsal-ventral or medial-lateral directions on dorsal column (DC) stimulation thresholds and neural activation regions. We used a two-stage computational model, including a finite element method model of field potentials in the spinal cord during stimulation, coupled to a biophysical cable model of mammalian, myelinated nerve fibers to calculate tissue impedance and nerve fiber activation within the DC. We found that SCS lead impedance was highly sensitive to the distance between the lead and cerebrospinal fluid (CSF) layer. In addition, among all the lead positions studied, medial-lateral movement resulted in the most substantial changes to SC activation regions. These results suggest that impedance can be used for detecting paddle position and lead migration, and therefore for guiding SCS programming.

  13. Stimulation of cardiovascular adaptability during prolonged space exposure

    NASA Technical Reports Server (NTRS)

    Gorman, H. A.

    1971-01-01

    The deconditioning effects of weightlessness on the cardiovascular system of astronauts are discussed. It is believed that man cannot tolerate indefinite exposure to weightlessness without considerable circulatory deterioration. Analyses of data collected from space flights to date substantiate these beliefs, and confirm the fact that some form of compensation must be provided to keep the cardiovascular system of space travelers properly conditioned. Sequential pulsatile devices were investigated to produce periodic hydrostatic pressure gradients in the venous system of eight subhuman primates. Intermittent venous pooling of blood in the extremities triggers and stimulates the vascular reflex mechanisms of the cardiovascular system that may have significant benefits in maintaining the circulatory system in proper tone under weightless conditions. Electrocardiograms, blood pressure measurements, cardiac output and stroke volume determinations were used to evaluate the efficiency of the described technique. Results were amazingly consistent to indicate an efficient system for intermittently exercising the heart within safe and medically acceptable limits.

  14. Maternal self-esteem, exposure to lead, and child neurodevelopment.

    PubMed

    Surkan, Pamela J; Schnaas, Lourdes; Wright, Rosalind J; Téllez-Rojo, Martha M; Lamadrid-Figueroa, Héctor; Hu, Howard; Hernández-Avila, Mauricio; Bellinger, David C; Schwartz, Joel; Perroni, Estela; Wright, Robert O

    2008-03-01

    The notion that maternal personality characteristics influence cognitive development in their children has been grounded in stress moderation theory. Maternal personality traits, such as self-esteem, may buffer maternal stressors or lead to improved maternal-child interactions that directly impact neurodevelopment. This can be extended to suggest that maternal personality may serve to attenuate or exacerbate the effects of other neurotoxicants, although this has not been studied directly. We examined whether mothers' self-esteem had a direct or main effect on their children's cognitive outcomes. We also explored the modifying effects of maternal self-esteem on the association between exposure to lead and neurodevelopment in these children. Study participants included 379 mother-child pairs from Mexico City. Data included the Coopersmith Self-Esteem Scale in mothers, children's Bayley's Scale of Infant Development (BSID) scores, and sociodemographic information. Linear regression was used to model the relationship between maternal self-esteem and the Bayley's Mental Development Index (MDI) and Psychomotor Development Index (PDI) scores at age 24 months using models stratified by levels of maternal self-esteem. In adjusted models, each point increase in maternal self-esteem was associated with children having 0.2 higher score on the Bayley's MDI (p=0.04). Similar results were observed using the PDI outcome. Moreover, there was evidence that maternal self-esteem attenuated the negative effects of lead exposure, although the interaction fell short of conventional levels of statistical significance.

  15. Transcriptome Changes in Hirschfeldia incana in Response to Lead Exposure.

    PubMed

    Auguy, Florence; Fahr, Mouna; Moulin, Patricia; El Mzibri, Mohamed; Smouni, Abdelaziz; Filali-Maltouf, Abdelkarim; Béna, Gilles; Doumas, Patrick

    2015-01-01

    Hirschfeldia incana, a pseudometallophyte belonging to the Brassicaceae family and widespread in the Mediterranean region, was selected for its ability to grow on soils contaminated by lead (Pb). The global comparison of gene expression using microarrays between a plant susceptible to Pb (Arabidopsis thaliana) and a Pb tolerant plant (H. incana) enabled the identification of a set of specific genes expressed in response to lead exposure. Three groups of genes were particularly over-represented by the Pb exposure in the biological processes categorized as photosynthesis, cell wall, and metal handling. Each of these gene groups was shown to be directly involved in tolerance or in protection mechanisms to the phytotoxicity associated with Pb. Among these genes, we demonstrated that MT2b, a metallothionein gene, was involved in lead accumulation, confirming the important role of metallothioneins in the accumulation and the distribution of Pb in leaves. On the other hand, several genes involved in biosynthesis of ABA were shown to be up-regulated in the roots and shoots of H. incana treated with Pb, suggesting that ABA-mediated signaling is a possible mechanism in response to Pb treatment in H. incana. This latest finding is an important research direction for future studies.

  16. Transcriptome Changes in Hirschfeldia incana in Response to Lead Exposure

    PubMed Central

    Auguy, Florence; Fahr, Mouna; Moulin, Patricia; El Mzibri, Mohamed; Smouni, Abdelaziz; Filali-Maltouf, Abdelkarim; Béna, Gilles; Doumas, Patrick

    2016-01-01

    Hirschfeldia incana, a pseudometallophyte belonging to the Brassicaceae family and widespread in the Mediterranean region, was selected for its ability to grow on soils contaminated by lead (Pb). The global comparison of gene expression using microarrays between a plant susceptible to Pb (Arabidopsis thaliana) and a Pb tolerant plant (H. incana) enabled the identification of a set of specific genes expressed in response to lead exposure. Three groups of genes were particularly over-represented by the Pb exposure in the biological processes categorized as photosynthesis, cell wall, and metal handling. Each of these gene groups was shown to be directly involved in tolerance or in protection mechanisms to the phytotoxicity associated with Pb. Among these genes, we demonstrated that MT2b, a metallothionein gene, was involved in lead accumulation, confirming the important role of metallothioneins in the accumulation and the distribution of Pb in leaves. On the other hand, several genes involved in biosynthesis of ABA were shown to be up-regulated in the roots and shoots of H. incana treated with Pb, suggesting that ABA-mediated signaling is a possible mechanism in response to Pb treatment in H. incana. This latest finding is an important research direction for future studies. PMID:26793211

  17. MATERNAL SELF-ESTEEM, EXPOSURE TO LEAD, AND CHILD NEURODEVELOPMENT

    PubMed Central

    Surkan, Pamela J.; Schnaas, Lourdes; Wright, Rosalind J.; Téllez-Rojo, Martha M.; Lamadrid-Figueroa, Héctor; Hu, Howard; Hernández-Avila, E. Mauricio; Bellinger, David C.; Schwartz, Joel; Perroni, Estela; Wright, Robert O.

    2008-01-01

    The notion that maternal personality characteristics influence cognitive development in their children has been grounded in stress moderation theory. Maternal personality traits, such as self-esteem, may buffer maternal stressors or lead to improved maternal-child interactions that directly impact neurodevelopment. This can be extended to suggest that maternal personality may serve to attenuate or exacerbate the effects of other neurotoxicants, although this has not been studied directly. We examined whether mothers’ self-esteem had a direct or main effect on their children's cognitive outcomes. We also explored the modifying effects of maternal self-esteem on the association between exposure to lead and neurodevelopment in these children. Study participants included 379 mother-child pairs from Mexico City. Data included the Coopersmith self-esteem scale in mothers, children's Bayley's Scale of Infant Development (BSID) scores, and sociodemographic information. Linear regression was used to model the relationship between maternal self-esteem and the Bayley's Mental Development Index (MDI) and Psychomotor Development Index (PDI) scores at age 24 months using regression models stratified by levels of maternal self-esteem. In adjusted models, each point increase in maternal self-esteem was associated with children having 0.2 higher score on the Bayley's MDI (p=0.04). Similar results were observed using the PDI outcome. Moreover, there was evidence that maternal self-esteem attenuated the negative effects of lead exposure, although the interaction fell short of conventional levels of statistical significance. PMID:18261800

  18. Radiation exposure benefit of a lead cap in invasive cardiology.

    PubMed

    Kuon, E; Birkel, J; Schmitt, M; Dahm, J B

    2003-10-01

    Occupational head exposure to radiation in cardiologists may cause radiation induced cataracts and an increased risk of brain cancer. To determine the effectiveness of 0.5 mm lead equivalent caps, not previously used in invasive cardiology, in comparison with a 1.0 mm lead equivalent ceiling mounted lead glass screen. An anthropomorphic Alderson-Rando phantom was used to represent the patient. Scatter entrance skin air kerma to the operator position (S-ESAK-O) was measured during fluoroscopy for all standard angulations and the S-ESAK-O per dose-area product (DAP) calculated, as applied to the phantom. Measured mean (SD) left/right anterior oblique angulation ratios of S-ESAK-O without lead devices were 23.1 (10.1), and varied as a function of tube angulation, body height, and angle of incidence. S-ESAK-O/DAP decreased with incremental operator body height by 10 (3)% per 10 cm. A 1.0 mm lead glass shield reduced mean S-ESAK-O/DAP originating from coronary angiography from 1089 (764) to 54 (29) nSv/Gy x cm2. A 0.5 mm lead cap was effective in lowering measured levels to 1.8 (1.1) nSv/Gy x cm2. Both devices together enabled attenuation to 0.5 (0.1) nSv/Gy x cm2. The most advantageous line of vision for protection of the operator's eyes was > or = 60 degrees rightward. Use of 0.5 mm lead caps proved highly effective, attenuating S-ESAK-O to 2.7 (2.0) x 10(-3) of baseline, and to 1.2 (1.4) x 10(-3) of baseline where there was an additional 1.0 mm lead glass shield. These results could vary according to the x ray systems used, catheterisation protocols, and correct use of radiation protection devices.

  19. Early umbilical cord clamping contributes to elevated blood lead levels among infants with higher lead exposure.

    PubMed

    Chaparro, Camila M; Fornes, Raymond; Neufeld, Lynnette M; Tena Alavez, Gilberto; Eguía-Líz Cedillo, Raúl; Dewey, Kathryn G

    2007-11-01

    To investigate whether infant iron status, modified by umbilical cord clamping time and infant feeding mode, affected infant blood lead concentration at 6 months of age. Participants were a subset of women and their infants randomized to receive early (10 seconds) or delayed (2 minutes) umbilical cord clamping and were monitored to 6 months postpartum in Mexico City. Iron and lead status was analyzed in maternal, placental, and 6-month infant blood samples. Baseline maternal lead exposure data and infant feeding data at 2, 4, and 6 months were collected. In the total sample, maternal blood lead concentration, infant ferritin, and breast-feeding practices predicted infant blood lead concentration. Among infants with higher placental blood lead concentration and breast-fed infants not receiving any iron-fortified formula or milk at 6 months, early clamping increased infant blood lead concentration, an effect mediated in part via decreased infant iron status. Early cord clamping, by decreasing infant iron status, contributes to higher blood lead concentrations at 6 months of age among infants at high risk.

  20. [Use of urine lead level as an exposure indicator and its relationship to blood lead].

    PubMed

    Moreira, Maria de Fátima Ramos; Neves, Eduardo Borba

    2008-09-01

    The aim of this work was to verify whether there are statistically significant correlation between the concentrations of lead in blood (Pb-B) and urine (Pb-U). Electrothermal atomic absorption spectrometry was used in the determination of lead concentration in biological material. Venous blood and spot urine were collected from workers occupationally exposed (95), adults (130) and children up to 15 years old (22) environmentally exposed. After a test showing significant differences between Pb-U and the three categories previously determined, cutting points for Pb-U were established to predict Pb-B values by the ROC curve. Thus, it is expected that Pb-B is lower than 10 microg.dL-(1) with Pb-U up to 0.55 microg.dL-(1), whereas lead levels in blood below 27.6 microg.dL-(1) are expected when the amount of the metal in urine is lower than 2.05 microg.dL-(1). So, urine can be used to replace blood for the assessment of the occupational exposure to lead. However, caution is advised in the case of environmental exposure, since urinary lead should be used just as an estimation of the metal content in blood.

  1. The social costs of childhood lead exposure in the post-lead regulation era.

    PubMed

    Muennig, Peter

    2009-09-01

    To estimate the benefits that might be realized if all children in the United States had a blood lead level of less than 1 microg/dL. Data were obtained from published and electronic sources. A Markov model was used to project lifetime earnings, reduced crime costs, improvements in health, and reduced welfare costs using 2 scenarios: (1) maintaining the status quo and (2) reducing the blood lead level of all children to less than 1 microg/dL. The cohort of US children between birth and age 6 years in 2008, with economic and health outcomes projected for 65 years. Increased primary prevention efforts aimed at reducing lead exposure among children and pregnant women. Societal costs and quality-adjusted life years (QALYs) gained. Reducing blood lead levels to less than 1 microg/dL among all US children between birth and age 6 years would reduce crime and increase on-time high school graduation rates later in life. The net societal benefits arising from these improvements in high school graduation rates and reductions in crime would amount to $50 000 (SD, $14 000) per child annually at a discount rate of 3%. This would result in overall savings of approximately $1.2 trillion (SD, $341 billion) and produce an additional 4.8 million QALYs (SD, 2 million QALYs) for US society as a whole. More aggressive programs aimed at reducing childhood lead exposure may produce large social benefits.

  2. [Chronic exposure to environmental lead in Chilean infants. II: Effects on the psychomotor development].

    PubMed

    Vega, J; Frenz, P; Marchetti, N; Torres, J; Kopplin, E; Delgado, I; Vega, F

    1999-01-01

    Lactating children are specially susceptible to lead toxicity due to their underdeveloped nervous system, lower body mass, higher intestinal absorption and lower elimination rates. To determine the effects of lead exposure, comparing Chilean lactating children residing in rural areas with low lead exposure, and in urban areas with high lead exposure. Newborns from public maternity hospitals of the rural locality of San Felipe and from Metropolitan Santiago, were recruited for the study. On admission to the study, umbilical cord and maternal blood samples were obtained and an inquiry about perinatal, sociohereditary and lead exposure history was done. Children were followed every 6 months until 24 months of age, measuring blood parameters and neurobehavioral development using Bayley scales. Three hundred twelve children from Santiago and 113 from San Felipe were studied. Maternal and children blood lead levels were higher in Santiago, but lower than those reported in other international studies. At 24 months of age, 4.5% of children from Santiago and 0.7% of children from San Felipe had levels over 10 micrograms/dl. No differences in neurobehavioral development were observed between children of both cities. At 24 months, scores of MDI scales were 91 in Santiago and 97 in San Felipe. The figures for PDI scale were 93 in Santiago and 93 in San Felipe. Main risk factors for a retarded neurobehavioral development were socieconomic level with a mean Odds ratio of 3.5 (0.99-12.4), made sex with an Odds ratio of 2.3 (1.09-5.07) and stimulation at home with an Odds ratio of 0.7 (0.53-0.82). In this cohort of children, no effect of lead levels on neurobehavioral development was found.

  3. Occupational Lead Exposure from Indoor Firing Ranges in Korea.

    PubMed

    Park, Won-Ju; Lee, Suk-Ho; Lee, Se-Ho; Yoon, Hye-Sik; Moon, Jai-Dong

    2016-04-01

    Military personnel often use ammunitions that contain lead. The present study aimed to identify the risks for lead exposure and lead poisoning among workers at indoor firing ranges. A special health examination, including blood lead level (BLL) testing, was performed for all 120 workers at the indoor firing ranges of the Republic of Korea's Air Force, Navy, and Armed Forces Athletic Corps. The overall mean BLL was 11.3 ± 9.4 µg/dL (range: 2.0-64.0 µg/dL). The arithmetic mean of the BLL for professional shooters belong to Armed Forces Athletic Corps was 14.0 ± 8.3 µg/dL, while those of shooting range managers and shooting range supervisors were 13.8 ± 11.1 µg/dL and 6.4 ± 3.1 µg/dL, respectively. One individual had a BLL of 64 µg/dL, and ultimately completed chelation treatment (with CaNa2-ethylenediaminetetraacetic acid) without any adverse effects. These findings indicate that indoor firing range workers are exposed to elevated levels of lead. Therefore, when constructing an indoor firing range, a specialist should be engaged to design and assess the ventilation system; and safety guidelines regarding ammunition and waste handling must be mandatory. Moreover, workplace environmental monitoring should be implemented for indoor firing ranges, and the workers should undergo regularly scheduled special health examinations.

  4. Occupational Lead Exposure from Indoor Firing Ranges in Korea

    PubMed Central

    Lee, Suk-Ho; Lee, Se-Ho; Yoon, Hye-Sik

    2016-01-01

    Military personnel often use ammunitions that contain lead. The present study aimed to identify the risks for lead exposure and lead poisoning among workers at indoor firing ranges. A special health examination, including blood lead level (BLL) testing, was performed for all 120 workers at the indoor firing ranges of the Republic of Korea’s Air Force, Navy, and Armed Forces Athletic Corps. The overall mean BLL was 11.3 ± 9.4 µg/dL (range: 2.0–64.0 µg/dL). The arithmetic mean of the BLL for professional shooters belong to Armed Forces Athletic Corps was 14.0 ± 8.3 µg/dL, while those of shooting range managers and shooting range supervisors were 13.8 ± 11.1 µg/dL and 6.4 ± 3.1 µg/dL, respectively. One individual had a BLL of 64 µg/dL, and ultimately completed chelation treatment (with CaNa2-ethylenediaminetetraacetic acid) without any adverse effects. These findings indicate that indoor firing range workers are exposed to elevated levels of lead. Therefore, when constructing an indoor firing range, a specialist should be engaged to design and assess the ventilation system; and safety guidelines regarding ammunition and waste handling must be mandatory. Moreover, workplace environmental monitoring should be implemented for indoor firing ranges, and the workers should undergo regularly scheduled special health examinations. PMID:27051231

  5. Lead exposure at firing ranges-a review.

    PubMed

    Laidlaw, Mark A S; Filippelli, Gabriel; Mielke, Howard; Gulson, Brian; Ball, Andrew S

    2017-04-04

    Lead (Pb) is a toxic substance with well-known, multiple, long-term, adverse health outcomes. Shooting guns at firing ranges is an occupational necessity for security personnel, police officers, members of the military, and increasingly a recreational activity by the public. In the United States alone, an estimated 16,000-18,000 firing ranges exist. Discharge of Pb dust and gases is a consequence of shooting guns. The objectives of this study are to review the literature on blood lead levels (BLLs) and potential adverse health effects associated with the shooting population. The search terms "blood lead", "lead poisoning", "lead exposure", "marksmen", "firearms", "shooting", "guns", "rifles" and "firing ranges" were used in the search engines Google Scholar, PubMed and Science Direct to identify studies that described BLLs in association with firearm use and health effects associated with shooting activities. Thirty-six articles were reviewed that included BLLs from shooters at firing ranges. In 31 studies BLLs > 10 μg/dL were reported in some shooters, 18 studies reported BLLs > 20 μg/dL, 17 studies > 30 μg/d, and 15 studies BLLs > 40 μg/dL. The literature indicates that BLLs in shooters are associated with Pb aerosol discharge from guns and air Pb at firing ranges, number of bullets discharged, and the caliber of weapon fired. Shooting at firing ranges results in the discharge of Pb dust, elevated BLLs, and exposures that are associated with a variety of adverse health outcomes. Women and children are among recreational shooters at special risk and they do not receive the same health protections as occupational users of firing ranges. Nearly all BLL measurements compiled in the reviewed studies exceed the current reference level of 5 μg/dL recommended by the U.S. Centers for Disease Control and Prevention/National Institute of Occupational Safety and Health (CDC/NIOSH). Thus firing ranges, regardless of type and user classification

  6. Stimulation of erythrocyte phosphatidylserine exposure by mercury ions

    SciTech Connect

    Eisele, Kerstin; Lang, Philipp A.; Kempe, Daniela S.; Klarl, Barbara A.; Niemoeller, Olivier; Wieder, Thomas; Huber, Stephan M.; Duranton, Christophe; Lang, Florian . E-mail: florian.lang@uni-tuebingen.de

    2006-01-15

    The sequelae of mercury intoxication include induction of apoptosis. In nucleated cells, Hg{sup 2+}-induced apoptosis involves mitochondrial damage. The present study has been performed to elucidate effects of Hg{sup 2+} in erythrocytes which lack mitochondria but are able to undergo apoptosis-like alterations of the cell membrane. Previous studies have documented that activation of a Ca{sup 2+}-sensitive erythrocyte scramblase leads to exposure of phosphatidylserine at the erythrocyte surface, a typical feature of apoptotic cells. The erythrocyte scramblase is activated by osmotic shock, oxidative stress and/or energy depletion which increase cytosolic Ca{sup 2+} activity and/or activate a sphingomyelinase leading to formation of ceramide. Ceramide sensitizes the scramblase to Ca{sup 2+}. The present experiments explored the effect of Hg{sup 2+} ions on erythrocytes. Phosphatidylserine exposure after mercury treatment was estimated from annexin binding as determined in FACS analysis. Exposure to Hg{sup 2+} (1 {mu}M) indeed significantly increased annexin binding from 2.3 {+-} 0.5% (control condition) to 23 {+-} 6% (n = 6). This effect was paralleled by activation of a clotrimazole-sensitive K{sup +}-selective conductance as measured by patch-clamp recordings and by transient cell shrinkage. Further experiments revealed also an increase of ceramide formation by {approx}66% (n = 7) after challenge with mercury (1 {mu}M). In conclusion, mercury ions activate a clotrimazole-sensitive K{sup +}-selective conductance leading to transient cell shrinkage. Moreover, Hg{sup 2+} increases ceramide formation. The observed mechanisms could similarly participate in the triggering of apoptosis in nucleated cells by Hg{sup 2+}.

  7. Impact of chronic lead exposure on selected biological markers.

    PubMed

    Jangid, Ambica P; John, P J; Yadav, D; Mishra, Sandhya; Sharma, Praveen

    2012-01-01

    Lead poisoning remains a major problem in India due to the lack of awareness of its ill effects among the clinical community. Blood lead, δ-aminolevulinic acid dehydratase (δ-ALAD) and zinc protoporphyrin (ZPP) concentrations are widely used as biomarkers for lead toxicity The present study was designed to determine the impact of chronic lead exposure on selected biological markers. A total of 250 subjects, of both sexes, ranging in age from 20 to 70 years, were recruited. On the basis of BLLs, the subjects were categorized into four groups: Group A (BLL: 0-10 μg/dl), Group B (BLL: 10-20 μg/dl). Group C (BLL: 20-30 μg/dl) and Group D (BLL: 30-40 μg/dl) having BLLs of 3.60 ± 2.71 μg/dl, 15.21 ± 2.65 μg/dl, 26.82 ± 2.53 μg/dl and 36.38 ± 2.83 μg/dl, respectively. Significant changes in biological markers due to elevated BLLs were noted. The relation of BLL and biological markers to demographic characteristics such as sex, habits, diet and substances abuse (smoking effect) were also studied in the present investigation. Males, urban population, non-vegetarians, and smokers had higher blood lead levels. δ-ALAD activity was found to be significantly lower with increased BLL (P < 0.001), while the ZPP level was significantly higher with increased BLL (P < 0.001). Further, BLL showed a negative correlation with δ-ALAD (r = -0.425, P < 0.001, N = 250) and a positive correlations with ZPP (r = 0.669, P < 0.001, N = 250). Chronic lead exposure affects the prooxidant-antioxidant equilibrium leading to cellular oxidative stress.

  8. Lifestyles, diets, and Native American exposure factors related to possible lead exposures and toxicity.

    PubMed

    Harris, S; Harper, B L

    2001-06-01

    Lead exposure is still a national concern, and it is possible that Native Americans who live on reservations and pursue traditional lifestyles may be at higher risk through both their unique exposure profiles and their potentially greater sensitivity. A major component of the exposure assessment is the diet. For tribal members, traditional lifestyles that include native foods, medicines, and traditional practices have evolved and proven to be the most healthful over many thousands of years of coexistence with the environment. However, a completely traditional diet may not be fully available for a variety of reasons; so, one must also consider the adverse health consequences caused by the loss of healthy native foods and medicines, the contamination of remaining native foods, the inability to practice one's religion, and the possibly lower quality of the substitute diet. Health evaluations of lead exposure on reservations should therefore consider at least two types of diets in addition to the typical suburban diet: (a) traditional diets composed of native foods and medicines that would result in increased exposure if the plants and animals are contaminated and (b) disadvantaged or commodity food diets that result in widespread vitamin and mineral deficits of the sort known to increase absorption of and response to lead. Additional exposure to lead might come from reservation housing which is often older, although the prevalence of lead-based paint on reservations is unknown. The degree of physiological response could also be affected by widespread exposures to other neurotoxins (such as mercury and PCBs in fish), underlying disease patterns, and genetics. Although each of these factors is plausible, their prevalence singly or in combination is unknown. Any correlation between these risk factors and blood lead levels on reservations is also unknown. This paper begins to address these gaps by discussing the range of traditional and current diets that may exist among

  9. Potential Mechanism Leading to Impaired Thermoregulation Following Microgravity Exposure

    NASA Technical Reports Server (NTRS)

    Crandall, C. G.; Etzel, R. A.

    1999-01-01

    Prolonged exposure to microgravity or its analogues impairs thermoregulation in humans evidenced by higher internal temperatures following the exposure during a thermal challenge. Although the mechanism leading to this response has not been clearly delineated, we identified that prolonged head-down tilt (HDT) markedly impairs thermoregulatory reflex control of skin blood flow, as demonstrated by an increased internal temperature threshold for cutaneous vasodilation, and by a reduced slope of the relationship between the elevation in skin blood flow relative to the elevation in internal temperature. Recently, Fortney et al. identified similar responses in two individuals following 115 days of microgravity exposure. One possible mechanism leading to altered cutaneous vasodilation during a thermal challenge following actual or simulated microgravity exposure may be associated with baroreflex-mediated attenuation in the elevation of skin blood flow. During a heat stress the elevation in skin blood flow is accomplished through a combination of increased cutaneous vascular conductance and cardiac output, both of which result in central venous pressure (CVP) decreasing 2-6 mmHg. Reductions in CVP of this magnitude in normothermia decrease muscle blood flow and skin blood flow presumably through unloading the cardiopulmonary baroreceptors. It is unclear whether the reduction in CVP, and accompanying cardiopulmonary baroreceptor unloading, during passive heating buffers the elevation in skin blood flow. That is, would the elevation in skin blood flow be greater if CVP did not decrease, or decreased to a lesser extent during the heat stress? Conversely, if CVP decreased to a greater extend during a thermal challenge following a perturbation such as prolonged HDT, would the elevation in skin blood flow be attenuated during that thermal challenge? Given that prolonged HDT decreases plasma volume and central venous pressure, such a finding would provide a plausible hypothesis

  10. Potential Mechanism Leading to Impaired Thermoregulation Following Microgravity Exposure

    NASA Technical Reports Server (NTRS)

    Crandall, C. G.; Etzel, R. A.

    1999-01-01

    Prolonged exposure to microgravity or its analogues impairs thermoregulation in humans evidenced by higher internal temperatures following the exposure during a thermal challenge. Although the mechanism leading to this response has not been clearly delineated, we identified that prolonged head-down tilt (HDT) markedly impairs thermoregulatory reflex control of skin blood flow, as demonstrated by an increased internal temperature threshold for cutaneous vasodilation, and by a reduced slope of the relationship between the elevation in skin blood flow relative to the elevation in internal temperature. Recently, Fortney et al. identified similar responses in two individuals following 115 days of microgravity exposure. One possible mechanism leading to altered cutaneous vasodilation during a thermal challenge following actual or simulated microgravity exposure may be associated with baroreflex-mediated attenuation in the elevation of skin blood flow. During a heat stress the elevation in skin blood flow is accomplished through a combination of increased cutaneous vascular conductance and cardiac output, both of which result in central venous pressure (CVP) decreasing 2-6 mmHg. Reductions in CVP of this magnitude in normothermia decrease muscle blood flow and skin blood flow presumably through unloading the cardiopulmonary baroreceptors. It is unclear whether the reduction in CVP, and accompanying cardiopulmonary baroreceptor unloading, during passive heating buffers the elevation in skin blood flow. That is, would the elevation in skin blood flow be greater if CVP did not decrease, or decreased to a lesser extent during the heat stress? Conversely, if CVP decreased to a greater extend during a thermal challenge following a perturbation such as prolonged HDT, would the elevation in skin blood flow be attenuated during that thermal challenge? Given that prolonged HDT decreases plasma volume and central venous pressure, such a finding would provide a plausible hypothesis

  11. Cadmium, lead and mercury exposure in non smoking pregnant women

    SciTech Connect

    Hinwood, A.L.; Callan, A.C.; Ramalingam, M.; Boyce, M.; Heyworth, J.; McCafferty, P.; Odland, J.Ø.

    2013-10-15

    Recent literature suggests that exposure to low concentrations of heavy metals may affect both maternal and child health. This study aimed to determine the biological heavy metals concentrations of pregnant women as well as environmental and dietary factors that may influence exposure concentrations. One hundred and seventy three pregnant women were recruited from Western Australia, each providing a sample of blood, first morning void urine, residential soil, dust and drinking water samples. Participants also completed a questionnaire which included a food frequency component. All biological and environmental samples were analysed for heavy metals using ICP-MS. Biological and environmental concentrations of lead and mercury were generally low (Median Pb Drinking Water (DW) 0.04 µg/L; Pb soil <3.0 µg/g; Pb dust 16.5 µg/g; Pb blood 3.67 µg/L; Pb urine 0.55; µg/L Hg DW <0.03; Hg soil <1.0 µg/g; Hg dust <1.0 µg/g; Hg blood 0.46 µg/L; Hg urine <0.40 µg/L). Cadmium concentrations were low in environmental samples (Median CdDW 0.02 µg/L; Cdsoil <0.30 ug/g; Cddust <0.30) but elevated in urine samples (Median 0.55 µg/L, creatinine corrected 0.70 µg/g (range <0.2–7.06 µg/g creatinine) compared with other studies of pregnant women. Predictors of increased biological metals concentrations in regression models for blood cadmium were residing in the Great Southern region of Western Australia and not using iron/folic acid supplements and for urinary cadmium was having lower household annual income. However, these factors explained little of the variation in respective biological metals concentrations. The importance of establishing factors that influence low human exposure concentrations is becoming critical in efforts to reduce exposures and hence the potential for adverse health effects. -- Highlights: • Biological heavy metals concentrations in women in their 3rd trimester of pregnancy. • Exposure assessment including environmental, lifestyle and activity

  12. Lead exposure in indigenous communities of the Amazon basin, Peru.

    PubMed

    Anticona, Cynthia; Bergdahl, Ingvar A; Lundh, Thomas; Alegre, Yuri; Sebastian, Miguel San

    2011-12-01

    Since 2006, three studies have reported elevated levels of lead (Pb) among the indigenous population of the Corrientes river, in the Amazon basin of Peru. Due to the large evidence of environmental pollution related to oil exploitation in the area, this activity has been suggested as the source of exposure. This study aimed to evaluate Pb levels in the population and environment of two communities exposed and one community non-exposed to the oil exploitation activity. Blood lead levels (BLL) were determined by the instrument Leadcare. A comparison with the graphite furnace atomic absorption technique was performed in order to validate the Leadcare results. Environmental samples were analyzed by inductively coupled plasma atomic emission spectroscopy. Among 361 capillary samples, the mean BLL was 9.4 μg/dl. Mean BLL of the communities exposed (n=171, x¯=9.5 μg/dl) and non-exposed (n=190, x¯=9.2 μg/dl) to the oil activity were not significantly different. Pb levels in environmental samples were below the maximum permissible levels. The sources of exposure could not be identified. Elevated levels of Pb in the oil-non-exposed community pointed out at other sources not yet clarified.

  13. The Yugoslavia Prospective Lead Study: contributions of prenatal and postnatal lead exposure to early intelligence.

    PubMed

    Wasserman, G A; Liu, X; Popovac, D; Factor-Litvak, P; Kline, J; Waternaux, C; LoIacono, N; Graziano, J H

    2000-01-01

    To investigate associations between the timing of lead (Pb) exposure on early intelligence, we examined the results of psychometric evaluations at ages 3, 4, 5, and 7 years, from 442 children whose mothers were recruited during pregnancy from a smelter town and a non-lead-exposed town in Yugoslavia. We compared the relative contribution of prenatal blood lead (BPb) with that of relative increases in BPb in either the early (0-2 years) or the later (from 2 years on) postnatal period to child intelligence measured longitudinally at ages 3 and 4 (McCarthy GCI), 5 (Wechsler Preschool and Primary Scale of Intelligence-Revised, WPPSI-R IQ), and 7 (Wechsler Intelligence Scale for Children-version III, WISC-III IQ), controlling for: Home Observation for Measurement of the Environment (HOME) quality; maternal age, intelligence, education, and ethnicity; and birthweight and gender. Elevations in both prenatal and postnatal BPb were associated with small decrements in young children's intelligence.

  14. Developmental lead exposure causes startle response deficits in zebrafish.

    PubMed

    Rice, Clinton; Ghorai, Jugal K; Zalewski, Kathryn; Weber, Daniel N

    2011-10-01

    Lead (Pb(2+)) exposure continues to be an important concern for fish populations. Research is required to assess the long-term behavioral effects of low-level concentrations of Pb(2+) and the physiological mechanisms that control those behaviors. Newly fertilized zebrafish embryos (<2h post fertilization; hpf) were exposed to one of three concentrations of lead (as PbCl(2)): 0, 10, or 30 nM until 24 hpf. (1) Response to a mechanosensory stimulus: Individual larvae (168 hpf) were tested for response to a directional, mechanical stimulus. The tap frequency was adjusted to either 1 or 4 taps/s. Startle response was recorded at 1000 fps. Larvae responded in a concentration-dependent pattern for latency to reaction, maximum turn velocity, time to reach V(max) and escape time. With increasing exposure concentrations, a larger number of larvae failed to respond to even the initial tap and, for those that did respond, ceased responding earlier than control larvae. These differences were more pronounced at a frequency of 4 taps/s. (2) Response to a visual stimulus: Fish, exposed as embryos (2-24 hpf) to Pb(2+) (0-10 μM) were tested as adults under low light conditions (≈ 60 μW/m(2)) for visual responses to a rotating black bar. Visual responses were significantly degraded at Pb(2+) concentrations of 30 nM. These data suggest that zebrafish are viable models for short- and long-term sensorimotor deficits induced by acute, low-level developmental Pb(2+) exposures.

  15. Relative contribution of lead from anthropogenic sources to the total human lead exposure in the United States. Final report

    SciTech Connect

    Elias, R.W.

    1986-08-01

    The paper evaluates human exposure to lead at a baseline level for persons living in non-urban communities away from stationary or mobile sources of lead, eating typical diets, and engaging in no lead-related occupational or avocational activities. Relative contributions of atmospheric and metallic lead are evaluated for each exposure pathway. For this baseline situation, perhaps 40 to 55% of the total human exposure to lead is of atmospheric origin. Beyond the baseline level, additional exposure factors can be determined for other environments (e.g. urban, occupational, smelter communities) and for certain habits and activities (e.g., pica, smoking, drinking, and various hobbies), with variations for age, sex, or socioeconomic status. Although quantification of these factors is uncertain, they provide guidelines in determining relative exposures under differing environmental conditions. The added exposure factors can also be partitioned into atmospheric, metallic, and pigment lead.

  16. Feather lead concentrations and (207)Pb/(206)Pb ratios reveal lead exposure history of California Condors (Gymnogyps californianus).

    PubMed

    Finkelstein, M E; George, D; Scherbinski, S; Gwiazda, R; Johnson, M; Burnett, J; Brandt, J; Lawrey, S; Pessier, A P; Clark, M; Wynne, J; Grantham, J; Smith, D R

    2010-04-01

    Lead poisoning is a primary factor impeding the survival and recovery of the critically endangered California Condor (Gymnogyps californianus). However, the frequency and magnitude of lead exposure in condors is not well-known in part because most blood lead monitoring occurs biannually, and biannual blood samples capture only approximately 10% of a bird's annual exposure history. We investigated the use of growing feathers from free-flying condors in California to establish a bird's lead exposure history. We show that lead concentration and stable lead isotopic composition analyses of sequential feather sections and concurrently collected blood samples provided a comprehensive history of lead exposure over the 2-4 month period of feather growth. Feather analyses identified exposure events not evident from blood monitoring efforts, and by fitting an empirically derived timeline to actively growing feathers, we were able to estimate the time frame for specific lead exposure events. Our results demonstrate the utility of using sequentially sampled feathers to reconstruct lead exposure history. Since exposure risk in individuals is one determinant of population health, our findings should increase the understanding of population-level effects from lead poisoning in condors; this information may also be helpful for other avian species potentially impacted by lead poisoning.

  17. Comparison of blood and tissue lead concentrations from cattle with known lead exposure.

    PubMed

    Bischoff, Karyn; Hillebrandt, Joseph; Erb, Hollis N; Thompson, Belinda; Johns, Sonia

    2016-10-01

    Blood lead (Pb) is used to diagnose Pb poisoning and exposure in cattle, but there are limited data comparing circulating Pb with concentrations in beef from the same cattle. This study determines whether there is a correlation between blood Pb and tissue Pb concentrations in accidentally exposed cattle. Pb analyses were carried out on ante-mortem blood and post-mortem tissues (including, if available, brain, liver, skeletal muscle, bone, gastrointestinal contents and kidney, and also foetal tissues from one cow) collected from 13 cattle known to have accidental Pb exposure and from three control cows with no known exposure. Variables from cattle were analysed statistically using a Shapiro-Wilk normality test and non-parametric descriptive and association statistics. Blood Pb from exposed cattle rank-correlated with liver, bone and kidney Pb concentrations, but not with the Pb concentrations of brain, skeletal muscle or gastrointestinal contents. The lowest blood Pb concentration associated with a detectable skeletal muscle Pb concentration (> 0.1 mg kg(-)(1) dry matter) was 4.57 μg dl(-1). Based on these findings, we recommend that cattle with blood Pb > 2.5 μg dl(-1) be withheld from slaughter and that liver, bone and kidney from all cattle with known Pb exposure be withheld from the human food chain.

  18. The Influence of Lead Exposure and Toxicity to Children's Neurological Development and School Performance.

    ERIC Educational Resources Information Center

    Kimball, Sarah L.

    This report discusses the effects of lead exposure and toxicity on children's cognitive development and school performance and addresses the role of schools in prevention of lead poisoning. Sources of lead exposure include mining, smelting and refining activities, lead paint, leaded gasoline, and industrial emissions. The results of lead poisoning…

  19. Air lead exposures and blood lead levels within a large automobile manufacturing workforce, 1980-1985.

    PubMed

    Kononen, D W; Kintner, H J; Bivol, K R

    1989-01-01

    Recent (1980-1985) trends in air lead (PbA) exposures and blood lead (PbB) levels experienced by approximately 10,000 workers employed in various stages of the automobile manufacturing process (i.e., auto assembly, lead-acid battery manufacture, foundry work, and "other" manufacturing-related operations) are described. Between 1980-1985, the mean PbB levels of assembly, battery, foundry, and "other" workers decreased by 28, 24, 3, and 27%, respectively, to 16.6, 23.6, 15.9, and 11.8 micrograms Pb/dl. Workers in the following job categories experienced the highest annual mean PbB levels: paste machine operators (battery plants), solder-grinders (assembly plants), and crane operators (foundries). During the same period, median 8-h Time Weighted Average PbA exposures (micrograms Pb/m3) in assembly plants, battery plants, and foundries decreased by 10, 12, and 20%, respectively, to 8.1, 13.6, and 10.9 micrograms/m3.

  20. Reproductive hazards of lead exposure among urban Egyptian men.

    PubMed

    El-Zohairy, E A; Youssef, A F; Abul-Nasr, S M; Fahmy, I M; Salem, D; Kahil, A K; Madkour, M K

    1996-01-01

    Fifty-five urban Egyptian males, aged 20-40, were assigned to two main groups to study the effects of their exposure to lead (Pb). Group I, infertile men (INF, n = 30), was divided into environmentally exposed (INF-E, n = 15) and environmentally and occupationally exposed (INF-EO, n = 15). A matching group (II) of fertile men (F, n = 25) was divided into fertile, environmentally exposed (F-E, n = 10), which was the control group, and fertile, environmentally and occupationally exposed (F-EO, n = 15). Semen parameters (i.e., count, morphology, motility, and volume), blood and semen Pb levels, and reproductive hormonal indices (i.e., serum testosterone, FSH, and LH) were measured in all subjects. Lead levels were always higher in blood than semen. Semen lead levels were significantly higher in all groups vs. the control (F-E) group. While no changes were observed in testosterone levels across groups, variable effects on LH and FSH levels were observed. Infertile-EO subjects showed a definite pattern of impaired semen parameters in comparison with infertile-E. No abnormalities were detected in hematologic, hepatic or renal function.

  1. A comparison of elementary schoolchildren's exposure to arsenic and lead.

    PubMed

    Chiang, Wan-Fu; Yang, Hao-Jan; Lung, Shih-Chun Candice; Huang, Shuai; Chiu, Chih-Yuan; Liu, I-Ling; Tsai, Ching-Ling; Kuo, Chung-Yih

    2008-01-01

    One hundred fifty seven fifth-grade students (aged 10-12 years) from three elementary schools in three different towns in Taichung County, Taiwan were chosen as study subjects for the present arsenic and lead exposure study. The three towns--Longgang, Shalach, and Shuntain--are known to be highly, moderately, and lightly (control) polluted by As and Pb, respectively. Spot morning urine samples of students were collected and analyzed for arsenic and lead. The levels of As in the urine of Longgang schoolchildren showed the highest value among the three schools, while those of the control group (Shuntain) had the lowest values. In addition, the levels of Pb in the urine of the schoolchildren in Shuntain were significantly lower than those in Longgang and Shalach, while the levels of Pb in the urine of the schoolchildren in Longgang and Shalach showed no significant difference. Results of daily intake of metals from the different exposure pathways (i.e., ingestion from drinking water, household dust and food, and inhalation from airborne particles) showed that the Longgang area had the highest daily intake of As and Pb among the three areas, while the lowest daily intake of As and Pb occurred in the control area (Shuntain). A significant correlation between the doses of daily intake and urinary concentrations of As (p = 0.002) and Pb (p = 0.020) was observed. This correlation suggests that the increase of unit dose of the daily intake for As resulted in an increase of 0.953 microg g(-1) creatinine of As, whereas the increase of unit dose of the daily intake for Pb led to an increase of 0.053 microg g(-1) creatinine of Pb. These data indicate that the level of As in urine increased about 18 times higher than that of Pb for the same amount of increase in daily intake.

  2. Feather lead concentrations and207Pb/206Pb ratios reveal lead exposure history of California condors (Gymnogyps californianus)

    USGS Publications Warehouse

    Finkelstein, M.E.; George, D.; Scherbinski, S.; Gwiazda, R.; Johnson, M.; Burnett, J.; Brandt, J.; Lawrey, S.; Pessier, Allan P.; Clark, M.; Wynne, J.; Grantham, And J.; Smith, D.R.

    2010-01-01

    Lead poisoning is a primary factor impeding the survival and recovery of the critically endangered California Condor (Gymnogyps californianus). However, the frequency and magnitude of lead exposure in condors is not well-known in part because most blood lead monitoring occurs biannually, and biannual blood samples capture only ???10% of a bird's annual exposure history. We investigated the use of growing feathers from free-flying condors in California to establish a bird's lead exposure history. We show that lead concentration and stable lead isotopic composition analyses of sequential feather sections and concurrently collected blood samples provided a comprehensive history of lead exposure over the 2-4 month period of feather growth. Feather analyses identified exposure events not evident from blood monitoring efforts, and by fitting an empirically derived timeline to actively growing feathers, we were able to estimate the time frame for specific lead exposure events. Our results demonstrate the utility of using sequentially sampled feathers to reconstruct lead exposure history. Since exposure risk in individuals is one determinant ?? 2010 American Chemical Society.

  3. Influence of abatement of lead exposure in Croatia on blood lead and ALAD activity.

    PubMed

    Zorana, Kljaković-Gašpić; Alica, Pizent; Jasna, Jurasović

    2016-01-01

    We evaluated the effect of lead (Pb) abatement measures in Croatia on blood lead (BPb) concentrations, and delta-aminolevulinic acid dehydratase (ALAD) activity in blood, as a sensitive indicator of early Pb effect. Data on BPb and ALAD activity were obtained from 829 Croatian men (19-64 years of age), with no known occupational exposure to metals. Data obtained in 2008-2009, after the ban of leaded gasoline in Croatia in 2006, were compared with similar data collected in 1981 and 1989, when the concentration of Pb in gasoline was 0.6 g/L. Our results showed a highly significant (p < 0.001) decrease in median BPb from 114.5 (range, 46.0-275.0) μg/L in 1981/1989 to 30.3 (range, 3.2-140.8) μg/L in 2008-2009 and an increase in median ALAD activity from 49.8 (range, 24.9-79.4) EU in 1981/1989 to 60.9 (range, 35.8-84.0) EU in 2008-2009. Individual factors influencing BPb values were, in the order of decreasing importance, Pb in ambient air (APb), alcohol consumption, age, and smoking. Increased ALAD activity was significantly associated with the decrease of APb, alcohol consumption, and smoking. These results show that lead abatement measures had a positive impact on both BPb concentrations (73.5% decrease) and the activity of ALAD (22.1% increase) in general population. Our results contribute to growing evidence that ALAD activity may be used as one of the earliest and sensitive diagnostic biomarkers of low-level Pb exposure.

  4. Hypothalamic sensing of ketone bodies after prolonged cerebral exposure leads to metabolic control dysregulation

    PubMed Central

    Carneiro, Lionel; Geller, Sarah; Hébert, Audrey; Repond, Cendrine; Fioramonti, Xavier; Leloup, Corinne; Pellerin, Luc

    2016-01-01

    Ketone bodies have been shown to transiently stimulate food intake and modify energy homeostasis regulatory systems following cerebral infusion for a moderate period of time (<6 hours). As ketone bodies are usually enhanced during episodes of fasting, this effect might correspond to a physiological regulation. In contrast, ketone bodies levels remain elevated for prolonged periods during obesity, and thus could play an important role in the development of this pathology. In order to understand this transition, ketone bodies were infused through a catheter inserted in the carotid to directly stimulate the brain for a period of 24 hours. Food ingested and blood circulating parameters involved in metabolic control as well as glucose homeostasis were determined. Results show that ketone bodies infusion for 24 hours increased food intake associated with a stimulation of hypothalamic orexigenic neuropeptides. Moreover, insulinemia was increased and caused a decrease in glucose production despite an increased resistance to insulin. The present study confirms that ketone bodies reaching the brain stimulates food intake. Moreover, we provide evidence that a prolonged hyperketonemia leads to a dysregulation of energy homeostasis control mechanisms. Finally, this study shows that brain exposure to ketone bodies alters insulin signaling and consequently glucose homeostasis. PMID:27708432

  5. Reducing lead in air and preventing childhood exposure near lead smelters: learning from the U.S. experience.

    PubMed

    Sullivan, Marianne

    2015-05-01

    Childhood lead exposure and poisoning near primary lead smelters continues in developed and developing countries. In the United States, the problem of lead poisoning in children caused by smelter emissions was first documented in the early 1970s. In 1978, Environmental Protection Agency set National Ambient Air Quality Standards for lead. Attainment of this lead standard in areas near operating lead smelters took twenty to thirty years. Childhood lead exposure and poisoning continued to occur after the lead National Ambient Air Quality Standards were set and before compliance was achieved. This article analyzes and discusses the factors that led to the eventual achievement of the 1978 lead National Ambient Air Quality Standards near primary smelters and the reduction of children's blood lead levels in surrounding communities. Factors such as federal and state regulation, monitoring of emissions, public health activities such as blood lead surveillance and health education, relocation of children, environmental group and community advocacy, and litigation all played a role.

  6. Environmental Lead Exposure and Otoacoustic Emissions in Andean Children

    PubMed Central

    Buchanan, Leo H.; Counter, S. Allen; Ortega, Fernando

    2012-01-01

    Studies relating sensory hearing impairment to lead (Pb) exposure in children have presented inconsistent results. The objective of this study was to measure distortion product otoacoustic emissions (DPOAE), sounds emanating from the outer hair cells of the inner ear, in Pb-exposed children to determine the effects of Pb poisoning on the inner ear. DPOAE were recorded for 9 f2 frequencies from 1187 to 7625 Hz on 102 ears of 53 Pb-exposed children (aged 6–16 years) residing in Pb-contaminated environments in the Andes Mountains of Ecuador where Pb-glazing of ceramics is the primary livelihood. Blood lead (PbB) levels ranged from 4.2 to 94.3 µg/dl (mean: 37.7; SD: 25.7; median: 36.4). The median PbB level was significantly higher than the CDC and WHO’s 10 µg/dl action level. Spearman rho correlation analyses of the relation between PbB level and DPOAE amplitude, and between PbB level and DPOAE signal-to-noise ratio revealed no significant associations at any of the f2 frequencies tested. In addition, no significant correlation (Spearman rho) between PbB level and hearing sensitivity for 6 pure-tone test frequencies from 1000–8000 Hz was found. Although the study group was found to have abnormally elevated PbB levels, in contrast to some earlier reports, the results of the current study showed no consistent Pb-induced sensory effects on the cochlea of Pb-intoxicated children. PMID:21830857

  7. Environmental lead exposure and otoacoustic emissions in Andean children.

    PubMed

    Buchanan, Leo H; Counter, S Allen; Ortega, Fernando

    2011-01-01

    Studies relating sensory hearing impairment to lead (Pb) exposure in children have presented inconsistent results. The objective of this study was to measure distortion product otoacoustic emissions (DPOAE), sounds emanating from the outer hair cells of the inner ear, in Pb-exposed children to determine the effects of Pb poisoning on the inner ear. DPOAE were recorded for 9 f(2) frequencies from 1187 to 7625 Hz on 102 ears of 53 Pb-exposed children (aged 6-16 yr) residing in Pb-contaminated environments in the Andes Mountains of Ecuador where Pb glazing of ceramics is the primary livelihood. Blood lead (PbB) levels ranged from 4.2 to 94.3 μg/dl (mean: 37.7; SD: 25.7; median: 36.4). The median PbB level was markedly higher than the Centers for Disease Control and Prevention (CDC) and World Health Organization (WHO) 10-μg/dl action level. Spearman rho correlation analyses of the relation between PbB level and DPOAE amplitude and between PbB level and DPOAE signal-to-noise ratio revealed no significant associations at any of the f(2) frequencies tested. In addition, no significant correlation (Spearman rho) between PbB level and hearing sensitivity for 6 pure-tone test frequencies from 1000 to 8000 Hz was found. Although the study group was found to have abnormally elevated PbB levels, in contrast to some earlier reports, the results of the current study showed no consistent Pb-induced sensory effects on the cochlea of Pb-intoxicated children.

  8. Childhood lead exposure in an industrial town in China: coupling stable isotope ratios with bioaccessible lead.

    PubMed

    Li, Hong-Bo; Chen, Kai; Juhasz, Albert L; Huang, Lei; Ma, Lena Q

    2015-04-21

    Fingerprinting based on stable isotopes of lead (Pb) in blood and environmental media helps to identify Pb exposure pathways in children. However, previous studies used stable isotopes of total Pb in media. In this study, a wire rope production town in China (Zhuhang) was selected for investigating the effectiveness of using isotope ratios in bioaccessible Pb to identify childhood Pb exposure pathways. Blood Pb levels of 115 children in Zhuhang were 1.7-20.4 μg dL(-1), averaging 6.1 ± 3.2 μg dL(-1) (mean ± standard deviation), and were ∼1.6 times the national average in China (3.9 ± 1.8 μg dL(-1)). Among different environmental media (housedust, soil, PM10, vegetables, rice, and drinking water), housedust (695 ± 495 mg kg(-1)) and vegetables [0.36 ± 0.40 mg (kg of fresh weight)(-1)] contained elevated Pb concentrations. The isotope ratios ((207)Pb/(206)Pb and (208)Pb/(206)Pb) of total Pb were the highest in housedust (0.8587 ± 0.0039 and 2.1049 ± 0.0087) but lower than blood Pb ratios (0.8634 ± 0.0027 and 2.1244 ± 0.0061). When using bioaccessible Pb in housedust (0.8639 ± 0.0018 and 2.1171 ± 0.0036), the isotope ratios overlapped with blood Pb ratios, suggesting that incidental ingestion of housedust was the predominant contributor to children's blood Pb. Coupling the stable isotope technique with bioaccessible Pb is more reliable for identifying Pb exposure pathways than total Pb determinations.

  9. Levels and source apportionment of children's lead exposure: could urinary lead be used to identify the levels and sources of children's lead pollution?

    PubMed

    Cao, Suzhen; Duan, Xiaoli; Zhao, Xiuge; Wang, Beibei; Ma, Jin; Fan, Delong; Sun, Chengye; He, Bin; Wei, Fusheng; Jiang, Guibin

    2015-04-01

    As a highly toxic heavy metal, the pollution and exposure risks of lead are of widespread concern for human health. However, the collection of blood samples for use as an indicator of lead pollution is not always feasible in most cohort or longitudinal studies, especially those involving children health. To evaluate the potential use of urinary lead as an indicator of exposure levels and source apportionment, accompanying with environmental media samples, lead concentrations and isotopic measurements (expressed as (207)Pb/(206)Pb, (208)Pb/(206)Pb and (204)Pb/(206)Pb) were investigated and compared between blood and urine from children living in the vicinities of a typical coking plant and lead-acid battery factory. The results showed urinary lead might not be a preferable proxy for estimating blood lead levels. Fortunately, urinary lead isotopic measurements could be used as an alternative for identifying the sources of children's lead exposure, which coincided well with the blood lead isotope ratio analysis.

  10. Analysis of the role of lead resistivity in specific absorption rate for deep brain stimulator leads at 3T MRI.

    PubMed

    Angelone, Leonardo M; Ahveninen, Jyrki; Belliveau, John W; Bonmassar, Giorgio

    2010-04-01

    Magnetic resonance imaging (MRI) on patients with implanted deep brain stimulators (DBSs) can be hazardous because of the antenna-effect of leads exposed to the incident radio-frequency field. This study evaluated electromagnetic field and specific absorption rate (SAR) changes as a function of lead resistivity on an anatomically precise head model in a 3T system. The anatomical accuracy of our head model allowed for detailed modeling of the path of DBS leads between epidermis and the outer table. Our electromagnetic finite difference time domain (FDTD) analysis showed significant changes of 1 g and 10 g averaged SAR for the range of lead resistivity modeled, including highly conductive leads up to highly resistive leads. Antenna performance and whole-head SAR were sensitive to the presence of the DBS leads only within 10%, while changes of over one order of magnitude were observed for the peak 10 g averaged SAR, suggesting that local SAR values should be considered in DBS guidelines. With rho(lead) = rho(copper) , and the MRI coil driven to produce a whole-head SAR without leads of 3.2 W/kg, the 1 g averaged SAR was 1080 W/kg and the 10 g averaged SAR 120 W/kg at the tip of the DBS lead. Conversely, in the control case without leads, the 1 g and 10 g averaged SAR were 0.5 W/kg and 0.6 W/kg, respectively, in the same location. The SAR at the tip of lead was similar with electrically homogeneous and electrically heterogeneous models. Our results show that computational models can support the development of novel lead technology, properly balancing the requirements of SAR deposition at the tip of the lead and power dissipation of the system battery.

  11. Analysis of the Role of Lead Resistivity in Specific Absorption Rate for Deep Brain Stimulator Leads at 3T MRI

    PubMed Central

    Angelone, Leonardo M.; Ahveninen, Jyrki; Belliveau, John W.; Bonmassar, Giorgio

    2011-01-01

    Magnetic resonance imaging (MRI) on patients with implanted deep brain stimulators (DBSs) can be hazardous because of the antenna-effect of leads exposed to the incident radio-frequency field. This study evaluated electromagnetic field and specific absorption rate (SAR) changes as a function of lead resistivity on an anatomically precise head model in a 3T system. The anatomical accuracy of our head model allowed for detailed modeling of the path of DBS leads between epidermis and the outer table. Our electromagnetic finite difference time domain (FDTD) analysis showed significant changes of 1 g and 10 g averaged SAR for the range of lead resistivity modeled, including highly conductive leads up to highly resistive leads. Antenna performance and whole-head SAR were sensitive to the presence of the DBS leads only within 10%, while changes of over one order of magnitude were observed for the peak 10 g averaged SAR, suggesting that local SAR values should be considered in DBS guidelines. With ρlead = ρcopper, and the MRI coil driven to produce a whole-head SAR without leads of 3.2 W/kg, the 1 g averaged SAR was 1080 W/kg and the 10 g averaged SAR 120 W/kg at the tip of the DBS lead. Conversely, in the control case without leads, the 1 g and 10 g averaged SAR were 0.5 W/kg and 0.6 W/kg, respectively, in the same location. The SAR at the tip of lead was similar with electrically homogeneous and electrically heterogeneous models. Our results show that computational models can support the development of novel lead technology, properly balancing the requirements of SAR deposition at the tip of the lead and power dissipation of the system battery. PMID:20335090

  12. Impact of the California Lead Ammunition Ban on Reducing Lead Exposure in Golden Eagles and Turkey Vultures

    PubMed Central

    Kelly, Terra R.; Bloom, Peter H.; Torres, Steve G.; Hernandez, Yvette Z.; Poppenga, Robert H.; Boyce, Walter M.; Johnson, Christine K.

    2011-01-01

    Predatory and scavenging birds may be exposed to high levels of lead when they ingest shot or bullet fragments embedded in the tissues of animals injured or killed with lead ammunition. Lead poisoning was a contributing factor in the decline of the endangered California condor population in the 1980s, and remains one of the primary factors threatening species recovery. In response to this threat, a ban on the use of lead ammunition for most hunting activities in the range of the condor in California was implemented in 2008. Monitoring of lead exposure in predatory and scavenging birds is essential for assessing the effectiveness of the lead ammunition ban in reducing lead exposure in these species. In this study, we assessed the effectiveness of the regulation in decreasing blood lead concentration in two avian sentinels, golden eagles and turkey vultures, within the condor range in California. We compared blood lead concentration in golden eagles and turkey vultures prior to the lead ammunition ban and one year following implementation of the ban. Lead exposure in both golden eagles and turkey vultures declined significantly post-ban. Our findings provide evidence that hunter compliance with lead ammunition regulations was sufficient to reduce lead exposure in predatory and scavenging birds at our study sites. PMID:21494329

  13. Impact of the California lead ammunition ban on reducing lead exposure in golden eagles and turkey vultures.

    PubMed

    Kelly, Terra R; Bloom, Peter H; Torres, Steve G; Hernandez, Yvette Z; Poppenga, Robert H; Boyce, Walter M; Johnson, Christine K

    2011-04-06

    Predatory and scavenging birds may be exposed to high levels of lead when they ingest shot or bullet fragments embedded in the tissues of animals injured or killed with lead ammunition. Lead poisoning was a contributing factor in the decline of the endangered California condor population in the 1980s, and remains one of the primary factors threatening species recovery. In response to this threat, a ban on the use of lead ammunition for most hunting activities in the range of the condor in California was implemented in 2008. Monitoring of lead exposure in predatory and scavenging birds is essential for assessing the effectiveness of the lead ammunition ban in reducing lead exposure in these species. In this study, we assessed the effectiveness of the regulation in decreasing blood lead concentration in two avian sentinels, golden eagles and turkey vultures, within the condor range in California. We compared blood lead concentration in golden eagles and turkey vultures prior to the lead ammunition ban and one year following implementation of the ban. Lead exposure in both golden eagles and turkey vultures declined significantly post-ban. Our findings provide evidence that hunter compliance with lead ammunition regulations was sufficient to reduce lead exposure in predatory and scavenging birds at our study sites.

  14. Lead exposure and growth in the early preschool child: A follow-up report from the Cincinnati Lead Study

    SciTech Connect

    Shukla, R.; Dietrich, K.N.; Bornschein, R.L.; Berger, O.; Hammond, P.B. )

    1991-11-01

    This report is a follow-up of an earlier study of the effects of low to moderate prenatal and postnatal lead exposure on children's growth in stature. Two hundred thirty-five subjects were assessed every 3 months for lead exposure (blood lead level) and stature (recumbent length) up to 33 months of age. Fetal lead exposure was indexed by maternal blood lead level during pregnancy. The adverse effects of lead on growth during the first year of life were reported previously. This analysis covers essentially the second and third years of life. The results indicate that mean blood lead level during this period was negatively associated with attained height at 33 months of age (P = .002). This association was, however, evidenced only among those children who had mean blood lead levels greater than the cohort median (greater than or equal to 10.77 micrograms/dL) during the 3- to 15-month interval. The results also suggest that the effect of lead exposure (both in utero as well as during the first year of life) are transient provided that subsequent exposure to lead is not excessive. It appears that maintaining an average blood lead level of 25 micrograms/dL or more during the second and third year of life was detrimental to the child's attained stature at 33 months of age. Approximately 15% of this cohort experienced these levels of lead exposure. Continued follow-up of this cohort will reveal whether these lead-related deficits persist and whether they continue to be dependent on the level of exposure in an earlier period.

  15. Lead exposure changes gastric acid secretion in rat: role of nitric oxide (NO).

    PubMed

    Vahedian, Zakieh; Nabavizadeh, Fatemeh; Keshavarz, Mansoor; Vahedian, Jalal; Mirershadi, Fatemeh

    2011-01-01

    Sub chronic exposure to lead in rats slows gastric emptying, but little is known about the effects of lead on gastric secretion. This study was designed to investigate the effects of lead on gastric acid secretion and its possible mechanisms in rats. Lead acetate was dissolved in drinking water in a concentration of 1%. Sodium acetate-containing water with a molar concentration similar to lead was also prepared. We had nine groups of animals (n=8); four of them were exposed to lead for 1, 2, 3, and 4 weeks (Pb1, Pb2, Pb3 and Pb4 groups, respectively). Sodium acetate solution was given to another four groups for 1, 2, 3, and 4 weeks (Na1, Na2, Na3 and Na4 groups, respectively). Gastric secretion was collected by washout technique and its acid output was measured in the basal (Basal Acid Output, BAO), vogotomy (Vagotomized Acid Output, VAO), and vagally stimulated (Vagally Stimulated Acid Output, VSAO) states using titrator instrument. Nitric oxide (NO) metabolite of gastric tissue was determined by Griess micro assay method to evaluate the possible mechanism of lead effect on gastric secretion. VSAO was significantly less in Pb1 and Pb2 groups than Na1 and Na2 ones respectively (1.75 ± 0.17, 2.10 ± 0.30 vs. 5.79 ± 0.20, 6.18 ± 0.27 µmol/15min) (P=0.001, P=0.001). BAO was significantly more in Pb3 and Pb4 groups than Na3 and Na4 ones respectively (2.77 ± 0.37, 2.80 ± 0.31 vs. 1.73 ± 0.16, 1.79 ± 0.34 µmol/15min) (P=0.01, P=0.02), but it was the same after vagotomy. VSAO was more in Pb3 and Pb4 groups than their Na counterparts (P=0.001, P=0.0001). NO metabolite of gastric tissue was more in all Pb groups in comparison to their Na counterparts (P=0.0001). In this study, it seems that lead exposure, via NO mechanism, has different effects on acid secretion. Nitric oxide in small and large amounts decrease and increase gastric acid secretion, respectively.

  16. Cranial plate anchoring of spinal cord stimulation paddle leads: technical note.

    PubMed

    Tomycz, Nestor D; Cameron, Jeffrey; Whiting, Donald M; Oh, Michael Y

    2012-09-01

    Lead migration is a frequent complication of spinal cord stimulation (SCS) and requires revision surgery. The evolution of wider paddle leads has necessitated more extensive laminotomy and epidural adhesiolysis, which may increase the risk of lead migration. We describe a novel anchoring technique for SCS paddle leads with use of a cranial "dogbone" plate. We retrospectively reviewed a consecutive series of 11 patients who underwent placement of paddle lead spinal cord stimulators with titanium plate anchoring. Patients were followed for a mean of 29.5 months from SCS implantation (range, 5-65 months). A 4-hole linear titanium cranial plate and two 4-mm screws were used to tightly affix the proximal paddle lead wiring to the lamina below the laminotomy defect. All patients continue to have satisfactory spinal cord stimulation with no loss of efficacy or need for revision. No complications have been attributed to titanium plate anchoring, and there have been no cases of lead migration with this technique. Titanium plate anchoring added minimal time (approximately 3-5 minutes) to the operative case. We report a safe and effective anchoring technique for paddle lead SCS with the use of a cranial plate. Our experience has been that this technique, which anchors the proximal lead wiring to the remaining lamina at the inferior laminotomy defect, is superior to anchoring methods that rely on suturing of lead wiring.

  17. MAPK pathway activation by chronic lead-exposure increases vascular reactivity through oxidative stress/cyclooxygenase-2-dependent pathways

    SciTech Connect

    Simões, Maylla Ronacher; Aguado, Andrea; Fiorim, Jonaína; Silveira, Edna Aparecida; Azevedo, Bruna Fernandes; Toscano, Cindy Medice; Zhenyukh, Olha; Briones, Ana María; Alonso, María Jesús; Vassallo, Dalton Valentim; Salaices, Mercedes

    2015-03-01

    Chronic exposure to low lead concentration produces hypertension; however, the underlying mechanisms remain unclear. We analyzed the role of oxidative stress, cyclooxygenase-2-dependent pathways and MAPK in the vascular alterations induced by chronic lead exposure. Aortas from lead-treated Wistar rats (1st dose: 10 μg/100 g; subsequent doses: 0.125 μg/100 g, intramuscular, 30 days) and cultured aortic vascular smooth muscle cells (VSMCs) from Sprague Dawley rats stimulated with lead (20 μg/dL) were used. Lead blood levels of treated rats attained 21.7 ± 2.38 μg/dL. Lead exposure increased systolic blood pressure and aortic ring contractile response to phenylephrine, reduced acetylcholine-induced relaxation and did not affect sodium nitroprusside relaxation. Endothelium removal and L-NAME left-shifted the response to phenylephrine more in untreated than in lead-treated rats. Apocynin and indomethacin decreased more the response to phenylephrine in treated than in untreated rats. Aortic protein expression of gp91(phox), Cu/Zn-SOD, Mn-SOD and COX-2 increased after lead exposure. In cultured VSMCs lead 1) increased superoxide anion production, NADPH oxidase activity and gene and/or protein levels of NOX-1, NOX-4, Mn-SOD, EC-SOD and COX-2 and 2) activated ERK1/2 and p38 MAPK. Both antioxidants and COX-2 inhibitors normalized superoxide anion production, NADPH oxidase activity and mRNA levels of NOX-1, NOX-4 and COX-2. Blockade of the ERK1/2 and p38 signaling pathways abolished lead-induced NOX-1, NOX-4 and COX-2 expression. Results show that lead activation of the MAPK signaling pathways activates inflammatory proteins such as NADPH oxidase and COX-2, suggesting a reciprocal interplay and contribution to vascular dysfunction as an underlying mechanisms for lead-induced hypertension. - Highlights: • Lead-exposure increases oxidative stress, COX-2 expression and vascular reactivity. • Lead exposure activates MAPK signaling pathway. • ROS and COX-2 activation by

  18. Radiation exposure in percutaneous spinal cord stimulation mapping: a preliminary report.

    PubMed

    Wininger, Kevin L; Deshpande, Kedar K; Deshpande, Keshav K

    2010-01-01

    The utilization of spinal cord stimulation (SCS) to treat intractable pain has increased substantially in recent years. Integral to this therapy, the fluoroscope assists with requisite mapping protocols during trialing procedures to identify topographical dermatomal representations of spinal segments, and its use demands measurements of radiation exposure. However, such data is not found in the literature. The aim of this study was to report on radiation exposure during percutaneous SCS trialing procedures. An observational study. A non-university out-patient Interventional Pain Management practice in the United States. Fluoroscopy time from 110 SCS trialing procedures performed in a non-university, outpatient setting was studied retrospectively. Summary statistics were reported for all procedures collectively, as well as for lead arrangement and location. The interventional spine team carried out all procedural cases with the same mobile C-arm fluoroscopy system. Incident air kerma was evaluated by simplistic modeling. Mean total fluoroscopy time was 133.4 s with a standard deviation of 84.8 s, and the mean percentage of time allocated to pulsed fluoroscopy was 31.9%. Fluoroscopy time for the most common lead arrangement/location, neural canal dual leads/low-thoracic (n=87), ranged from 28.5 s to 387.4 s. Incident air kerma was 1.8-43.7 mGy. A preliminary report with a sample size of 110. Various lead placement options are available to the spinal interventionalist to treat pain with SCS. Our data set provides first steps to obtain benchmark reference estimates on fluoroscopy times and radiation exposure during SCS trialing procedures/spinal segment mapping. Fluoroscopy times for such interventions may be considerable when compared to more commonly performed pain medicine procedures; however, skin injury is improbable.

  19. Lead exposure: Public and Occupational Health Hazards. (Latest citations from Pollution Abstracts). Published Search

    SciTech Connect

    Not Available

    1992-06-01

    The bibliography contains citations concerning the effects of chronic lead exposure in humans and animals. The citations explore lead exposure resulting from occupational hazards, automobile emissions, and air pollution. Lead absorption in children is discussed. The clinical features of lead toxicity are noted, and biochemical assays for the quantification of blood and tissue lead levels are discussed. D-aminolevulenic acid dehydratase and its relation to blood lead levels are cited. (Contains 250 citations and includes a subject term index and title list.)

  20. Childhood Exposure to Lead: A Common Cause of School Failure.

    ERIC Educational Resources Information Center

    Needleman, Herbert L.

    1992-01-01

    According to the U.S. Public Health Service, lead poisoning remains the most common and societally devastating environmental disease of young children. About 16 percent all American children have blood lead levels in the neurotoxic range. Being poor dramatically increases this risk. The lead industry has long camouflaged lead's toxicity.…

  1. Lead exposure in radiator repair workers: a survey of Washington State radiator repair shops and review of occupational lead exposure registry data.

    PubMed

    Whittaker, Stephen G

    2003-07-01

    Radiator repair workers in Washington State have the greatest number of very elevated (> or =60 microg/dL) blood lead levels of any other worker population. The goals of this study were to determine the number of radiator repair workers potentially exposed to lead; estimate the extent of blood lead data underreporting to the Occupational Lead Exposure Registry; describe current safety and health practices in radiator repair shops; and determine appropriate intervention strategies to reduce exposure and increase employer and worker awareness. Lead exposure in Washington State's radiator repair workers was assessed by reviewing Registry data and conducting a statewide survey of radiator repair businesses. This study revealed that a total of 226 workers in Washington State (including owner-operators and all employees) conduct repair activities that could potentially result in excessive exposures to lead. Approximately 26% of radiator repair workers with elevated blood lead levels (> or =25 microg/dL) were determined to report to Washington State's Registry. This study also revealed a lack of awareness of lead's health effects, appropriate industrial hygiene controls, and the requirements of the Lead Standard. Survey respondents requested information on a variety of workplace health and safety issues and waste management; 80% requested a confidential, free-of-charge consultation. Combining data derived from an occupational health surveillance system and a statewide mail survey proved effective at characterizing lead exposures and directing public health intervention in Washington State.

  2. Developmental Ethanol Exposure Leads to Long-Term Deficits in Attention and Its Underlying Prefrontal Circuitry

    PubMed Central

    Bignell, Warren

    2016-01-01

    Abstract Chronic prenatal exposure to ethanol can lead to a spectrum of teratogenic outcomes that are classified in humans as fetal alcohol spectrum disorders (FASD). One of the most prevalent and persistent neurocognitive components of FASD is attention deficits, and it is now thought that these attention deficits differ from traditional attention deficit hyperactivity disorder (ADHD) in their quality and response to medication. However, the neuronal mechanisms underlying attention deficits in FASD are not well understood. We show here that after developmental binge-pattern ethanol exposure, adult mice exhibit impaired performance on the five-choice serial reaction time test for visual attention, with lower accuracy during initial training and a higher rate of omissions under challenging conditions of high attention demand. Whole-cell electrophysiology experiments in these same mice find dysregulated pyramidal neurons in layer VI of the medial prefrontal cortex, which are critical for normal attention performance. Layer VI neurons show decreased intrinsic excitability and increased responses to stimulation of both nicotinic acetylcholine receptors and α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) glutamate receptors. Moreover, although nicotinic acetylcholine responses correlate with performance on the five-choice task in control mice, these relationships are completely disrupted in mice exposed to ethanol during development. These findings demonstrate a novel outcome of developmental binge-pattern ethanol exposure and suggest that persistent alterations to the function of prefrontal layer VI neurons play an important mechanistic role in attention deficits associated with FASD. PMID:27844059

  3. Toxic exposure of songbirds to lead in the Southeast Missouri Lead Mining District

    USGS Publications Warehouse

    Beyer, W. Nelson; Franson, J. Christian; French, John B.; May, Thomas; Rattner, Barnett A.; Shearn-Bochsler, Valerie I.; Warner, Sarah E.; Weber, John; Mosby, David

    2013-01-01

    Mining and smelting in the Southeast Missouri Lead Mining District has caused widespread contamination of soils with lead (Pb) and other metals. Soils from three study sites sampled in the district contained from approximately 1,000–3,200 mg Pb/kg. Analyses of earthworms [33–4,600 mg Pb/kg dry weight (dw)] collected in the district showed likely high Pb exposure of songbirds preying on soil organisms. Mean tissue Pb concentrations in songbirds collected from the contaminated sites were greater (p < 0.05) than those in songbirds from reference sites by factors of 8 in blood, 13 in liver, and 23 in kidney. Ranges of Pb concentrations in livers (mg Pb/kg dw) were as follows: northern cardinal (Cardinalis cardinalis) = 0.11–3.0 (reference) and 1.3–30 (contaminated) and American robin (Turdus migratorius) = 0.43–8.5 (reference) and 7.6–72 (contaminated). Of 34 adult and juvenile songbirds collected from contaminated sites, 11 (32 %) had hepatic Pb concentrations that were consistent with adverse physiological effects, 3 (9 %) with systemic toxic effects, and 4 (12 %) with life-threatening toxic effects. Acid-fast renal intranuclear inclusion bodies, which are indicative of Pb poisoning, were detected in kidneys of two robins that had the greatest renal Pb concentrations (952 and 1,030 mg/kg dw). Mean activity of the enzyme delta-aminolevulinic acid dehydratase (ALAD) in red blood cells, a well-established bioindicator of Pb poisoning in birds, was decreased by 58–82 % in songbirds from the mining sites. We conclude that habitats within the mining district with soil Pb concentrations of ≥1,000 mg Pb/kg are contaminated to the extent that they are exposing ground-feeding songbirds to toxic concentrations of Pb.

  4. Toxic exposure of songbirds to lead in the Southeast Missouri Lead Mining District.

    PubMed

    Beyer, W Nelson; Franson, J Christian; French, John B; May, Thomas; Rattner, Barnett A; Shearn-Bochsler, Valerie I; Warner, Sarah E; Weber, John; Mosby, David

    2013-10-01

    Mining and smelting in the Southeast Missouri Lead Mining District has caused widespread contamination of soils with lead (Pb) and other metals. Soils from three study sites sampled in the district contained from approximately 1,000-3,200 mg Pb/kg. Analyses of earthworms [33-4,600 mg Pb/kg dry weight (dw)] collected in the district showed likely high Pb exposure of songbirds preying on soil organisms. Mean tissue Pb concentrations in songbirds collected from the contaminated sites were greater (p < 0.05) than those in songbirds from reference sites by factors of 8 in blood, 13 in liver, and 23 in kidney. Ranges of Pb concentrations in livers (mg Pb/kg dw) were as follows: northern cardinal (Cardinalis cardinalis) = 0.11-3.0 (reference) and 1.3-30 (contaminated) and American robin (Turdus migratorius) = 0.43-8.5 (reference) and 7.6-72 (contaminated). Of 34 adult and juvenile songbirds collected from contaminated sites, 11 (32%) had hepatic Pb concentrations that were consistent with adverse physiological effects, 3 (9%) with systemic toxic effects, and 4 (12%) with life-threatening toxic effects. Acid-fast renal intranuclear inclusion bodies, which are indicative of Pb poisoning, were detected in kidneys of two robins that had the greatest renal Pb concentrations (952 and 1,030 mg/kg dw). Mean activity of the enzyme delta-aminolevulinic acid dehydratase (ALAD) in red blood cells, a well-established bioindicator of Pb poisoning in birds, was decreased by 58-82% in songbirds from the mining sites. We conclude that habitats within the mining district with soil Pb concentrations of ≥1,000 mg Pb/kg are contaminated to the extent that they are exposing ground-feeding songbirds to toxic concentrations of Pb.

  5. Childhood lead exposure and uptake in teeth in the Cleveland area during the era of leaded gasoline.

    PubMed

    Robbins, Norman; Zhang, Zhong-Fa; Sun, Jiayang; Ketterer, Michael E; Lalumandier, James A; Shulze, Richard A

    2010-09-01

    Childhood uptake of lead from exposure to atmospheric leaded gasoline in the United States has been studied using mainly blood lead levels. Since reliable blood lead techniques were used only after the peak use of leaded gasoline, the prior exposure history is unclear. The well-documented decline in blood lead levels after the mid-1970s could represent the continuation of a historic steady decline in exposure from many sources. Alternatively, the post-1970s decline might represent the declining phase of a unimodal rise and fall corresponding closely to usage of leaded gasoline. To assess these possibilities, lead concentration and 207Pb/206Pb isotope ratios were measured in the enamel of permanent molar teeth formed between 1936 and 1993 in mainly African-American donors who grew up in the Cleveland area. Tooth enamel preserves the lead concentration and isotope ratio that prevails during tooth formation. Historical trends in enamel lead concentration were significantly correlated with surrogates of atmospheric lead exposure: lead in sediments of two dated Lake Erie cores, and lead consumed in gasoline. About two-thirds of the total lead uptake into enamel in this period was attributable to leaded gasoline, and the remainder to other sources (e.g. paint). Enamel 207Pb/206Pb isotope ratios were similar to those of one lake sediment. Multivariate analysis revealed significant correlation in neighborhoods with higher levels of traffic, and including lake sediment data, accounted for 53% of the variation in enamel lead levels. Enamel lead concentration was highly correlated with reported African-American childhood blood levels. The extrapolated peak level of 48microg/dL (range 40 to 63) is associated with clinical and behavioral impairments, which may have implications for adults who were children during the peak gasoline lead exposure. In sum, leaded gasoline emission was the predominant source of lead exposure of African-American Cleveland children during the latter

  6. Investigation of lead concentrations in whole blood, plasma and urine as biomarkers for biological monitoring of lead exposure.

    PubMed

    Sommar, Johan Nilsson; Hedmer, Maria; Lundh, Thomas; Nilsson, Leif; Skerfving, Staffan; Bergdahl, Ingvar A

    2014-01-01

    Lead in blood is a major concept in biomonitoring of exposure but investigations of its alternatives are scarce. The aim of the study was to describe different lead biomarkers' variances, day-to-day and between individuals, estimating their fraction of the total variance. Repeated sampling of whole blood, plasma and urine were conducted for 48 lead-exposed men and 20 individuals under normal environmental lead exposure, in total 603 measurements. For lead workers, the fraction of the total variance attributed to differences between individuals was 91% for whole-blood lead (geometric mean 227 μg/l; geometric standard deviation (GSD): 1.55 μg/l); plasma 78% (0.57 μg/l; GSD: 1.84 μg/l); density-adjusted urine 82%; and unadjusted urine 75% (23.7 μg/l; GSD: 2.48 μg/l). For the individuals under normal lead exposure, the corresponding fractions were 95% of the total variance for whole blood (20.7 μg/l; GSD: 8.6 μg/l), 15% for plasma (0.09 μg/l; GSD: 0.04 μg/l), 87% for creatinine-adjusted urine and 34% for unadjusted (10.8 μg/l; GSD: 6.7 μg/l). Lead concentration in whole blood is the biomarker with the best ability to discriminate between individuals with different mean concentration. Urinary and plasma lead also performed acceptably in lead workers, but at low exposures plasma lead was too imprecise. Urinary adjustments appear not to increase the between-individual fraction of the total variance among lead workers but among those with normal lead exposure.

  7. Interrelations of lead levels in bone, venous blood, and umbilical cord blood with exogenous lead exposure through maternal plasma lead in peripartum women.

    PubMed Central

    Chuang, H Y; Schwartz, J; Gonzales-Cossio, T; Lugo, M C; Palazuelos, E; Aro, A; Hu, H; Hernandez-Avila, M

    2001-01-01

    Recent research has raised the possibility that fetal lead exposure is not estimated adequately by measuring lead content in maternal whole blood lead because of the variable partitioning of lead in whole blood between plasma and red blood cells. Lead in maternal plasma may derive in large part from maternal bone lead stores. In this study we aimed to estimate the contribution of maternal whole blood lead, maternal bone lead levels, and environmental lead to umbilical cord blood lead levels (as a measure of fetal lead exposure). In the model, we assumed that lead from all of these sources reaches the fetus through the maternal plasma lead pathway. In 1994-1995, we recruited 615 pregnant women for a study of lead exposure and reproductive outcomes in Mexico City. We gathered maternal and umbilical cord blood samples within 12 hr of each infant's delivery and measured maternal lead levels in cortical bone and trabecular bone by a K-X-ray fluorescence (K-XRF) instrument within 1 month after delivery. We administered a questionnaire to assess use of lead-glazed ceramics (LGC) to cook food and we obtained data on regional air lead levels during the 2 months before delivery. We used structural equation models (SEMs) to estimate plasma lead as the unmeasured (latent) variable and to quantify the interrelations of plasma lead, the other lead biomarkers, and environmental lead exposure. In the SEM analysis, a model that allowed plasma lead to vary freely from whole blood lead explained the variance of cord blood lead (as reflected by a total model R(2); R(2) = 0.79) better than did a model without plasma lead (r(2) = 0.67). Cortical bone lead, trabecular bone lead, use of LGC, and mean air lead level contributed significantly to plasma lead. The exchange of lead between plasma and red blood cells was mostly in the direction of plasma to cells. According to the final model, an increase in trabecular bone lead and cortical bone lead was associated with increases in cord blood

  8. Cervical spinal cord stimulation with 5-column paddle lead in Raynaud's disease.

    PubMed

    Issa, Mohammed A; Kim, Chong H

    2012-01-01

    To report a case of Raynaud disease and its successful treatment with spinal cord stimulation utilizing the newly designed five-column Penta lead paddle. Specific electrode design, programming characteristics, and surgical technique are also discussed in this case. Case Report. University pain management center. A 65-year-old man with Raynaud disease presented with neck and upper extremity pain. The patient also had herniation and spondylosis of the lumbar spine and intervertebral disc disease of the cervical spine. An examination revealed venous changes, chronic ulceration, and digit discoloration in upper and lower extremities. Conservative management and pharmacological treatment were ineffective. Sympathetic block produced significant but limited improvement. Treatment with spinal cord stimulation was tried after a successful 7-day trial. Initial stimulation of the cervical spine with two octapolar leads at the C2 level produced greater than 75% pain improvement. However, the patient lost coverage shortly after discharge due to lead migration which could not be regained with reprogramming. A revision with Penta lead paddles produced sustainable and significant paresthesia coverage. A case report. We report the successful application of spinal cord stimulation utilizing a five-column paddle lead in an individual with severe refractory Raynaud disease.

  9. [Treatment of an infection from an intravenous cardiac stimulation lead with extracorporeal circulation].

    PubMed

    Castedo Mejuto, E; Toquero Ramos, J; Burgos Lázaro, R; García Montero, C; Castro Conde, A; Ortigosa Aso, J; Ugarte Basterrechea, J

    1999-08-01

    The infection of a transvenous lead implanted for cardiac stimulation is a rare but serious complication, because it can lead to the development of septicemia, tricuspid endocarditis, recurrent pulmonary emboli or thrombus formation in right cardiac chambers. The most efficient treatment is the removal of the entire pacing system (generator and lead). We describe our experience with the removal of infected leads with the aid of cardiopulmonary bypass. Indications of this technique and its advantages and disadvantages over the percutaneous extraction methods are discussed. A review of the literature is also presented.

  10. Renal ultrastructure, renal function, and parameters of lead toxicity in workers with different periods of lead exposure

    PubMed Central

    CramÉr, Kim; Goyer, Robert A.; Jagenburg, Rudolf; Wilson, Marion H.

    1974-01-01

    Cramér, K., Goyer, R. A., Jagenburg, R., and Wilson, Marion H. (1974).British Journal of Industrial Medicine,31, 113-127. Renal ultrastructure, renal function, and parameters of lead toxicity in workers with different periods of lead exposure. Renal biopsies were obtained from five men with heavy occupational exposure to lead and compared with studies of their renal function and parameters of lead toxicity. Two men had lead exposure of less than one year while three men had been exposed for from four to more than 30 years. In addition, renal function studies were performed in two men from whom renal biopsies could not be obtained. Their lead exposures were five and 12 years, respectively. Significantly lower plasma levels, when compared with non-exposed controls, were found for proline, valine, tyrosine, and phenylalanine although no excessive aminoaciduria was found. Renal function tests were normal in all except for a reduced glomerular filtration rate (GFR) in one worker. Plasma ALA was measured by a new and highly specific method and ALA clearance was found to follow GFR closely. Those workers with prolonged lead exposure showed a lower urinary lead excreation. Typical lead-induced intranuclear inclusion bodies were found only in those with short exposure. The ultrastructural changes were localized to the proximal tubules, while the glomeruli were only nonspecifically affected. Mitochondrial changes were found in all men. Reasons for the decrease in inclusion body formation in chronic lead nephropathy are uncertain but may be due to an increased rate of renal cell turnover or a consequence of chelation therapy. Images PMID:4830763

  11. Management of phrenic nerve stimulation caused by epicardial pacemaker leads in children.

    PubMed

    Wells, Winfield J; Batra, Anjan S

    2003-11-01

    To find a suitable site with good sensing and low pacing thresholds, it may be necessary to place an epicardial pacemaker lead in close proximity to the phrenic nerve. To prevent phrenic stimulation, a silastic patch can be sewn over the area of the pacing electrode to shield it from the nerve. This simple technique prevents diaphragm contraction and has not interfered with long-term pacemaker lead function.

  12. Change in childhood lead exposure prevalence with new reference level.

    PubMed

    Leafe, Morgan; Irigoyen, Matilde; DeLago, Cynthia; Hassan, Amman; Braitman, Leonard

    2015-06-01

    In 2012, the Centers for Disease Control and Prevention changed the "actionable" reference blood lead level from 10 μg/dL to 5 μg/dL, representing the highest 2.5 percentile of lead levels nationwide. In a high-risk urban community, the prevalence of children classified as lead exposed increased ninefold, from 1% to 9.1% (p < .0001) with the new reference level. This dramatic increase in the prevalence of children newly classified as lead exposed will require additional health care and public health resources for tracking, surveillance, and home lead abatement.

  13. Percutaneous adjustment method for transversely migrated spinal cord stimulation leads: a technical report.

    PubMed

    Jeon, Sang Yoon; Ji, Jae Young; Yoo, Sie Hyeon; Chon, Jin Young; Jung, Sung Hoon; Moon, Ho Sik

    2015-12-01

    Lead migration is the most common complication of spinal cord stimulation (SCS). However, the only corrective method for lead migration is revision surgery, which may cause additional complications. Here, we describe a new technique for adjusting a transversely migrated SCS lead. The medical records of four patients diagnosed with complex regional pain syndrome (n = 3) or failed back surgery syndrome (n = 1) who underwent implantation of percutaneous leads for SCS were retrospectively reviewed. Transverse lead migration was diagnosed radiographically after patients reported recurrence of pain or numbness in treated sites. The guide wire from the SCS implant kit was bent and inserted into the target epidural space using a 14-gauge Tuohy needle. When the guide wire contacted the migrated SCS lead, they were advanced to the correct location under C-arm guidance. After re-adjustment of the SCS lead, good coverage of the electrical stimulation was confirmed. Patients were followed for 9-19 months and they reported satisfactory pain relief and good electrical coverage after adjusting the SCS lead. Here, we describe a new technique for adjusting a transversely migrated SCS lead using a percutaneous epidural approach as a simple, safe, and cost-effective alternative to revision surgery.

  14. Neuromuscular electrical stimulation leads to physiological gains enhancing postural balance in the pre-frail elderly

    PubMed Central

    Mignardot, Jean-Baptiste; Deschamps, Thibault; Le Goff, Camille G; Roumier, François-Xavier; Duclay, Julien; Martin, Alain; Sixt, Marc; Pousson, Michel; Cornu, Christophe

    2015-01-01

    Physiological aging leads to a progressive weakening of muscles and tendons, thereby disturbing the ability to control postural balance and consequently increasing exposure to the risks of falls. Here, we introduce a simple and easy-to-use neuromuscular electrical stimulation (NMES) training paradigm designed to alleviate the postural control deficit in the elderly, the first hallmarks of which present as functional impairment. Nine pre-frail older women living in a long-term care facility performed 4 weeks of NMES training on their plantarflexor muscles, and seven nontrained, non-frail older women living at home participated in this study as controls. Participants were asked to perform maximal voluntary contractions (MVC) during isometric plantarflexion in a lying position. Musculo-tendinous (MT) stiffness was assessed before and after the NMES training by measuring the displacement of the MT junction and related tendon force during MVC. In a standing position, the limit of stability (LoS) performance was determined through the maximal forward displacement of the center of foot pressure, and related postural sway parameters were computed around the LoS time gap, a high force requiring task. The NMES training induced an increase in MVC, MT stiffness, and LoS. It significantly changed the dynamics of postural balance as a function of the tendon property changes. The study outcomes, together with a multivariate analysis of investigated variables, highlighted the benefits of NMES as a potential tool in combating neuromuscular weakening in the elderly. The presented training-based strategy is valuable in alleviating some of the adverse functional consequences of aging by directly acting on intrinsic biomechanical and muscular properties whose improvements are immediately transferable into a functional context. PMID:26229006

  15. Neuromuscular electrical stimulation leads to physiological gains enhancing postural balance in the pre-frail elderly.

    PubMed

    Mignardot, Jean-Baptiste; Deschamps, Thibault; Le Goff, Camille G; Roumier, François-Xavier; Duclay, Julien; Martin, Alain; Sixt, Marc; Pousson, Michel; Cornu, Christophe

    2015-07-01

    Physiological aging leads to a progressive weakening of muscles and tendons, thereby disturbing the ability to control postural balance and consequently increasing exposure to the risks of falls. Here, we introduce a simple and easy-to-use neuromuscular electrical stimulation (NMES) training paradigm designed to alleviate the postural control deficit in the elderly, the first hallmarks of which present as functional impairment. Nine pre-frail older women living in a long-term care facility performed 4 weeks of NMES training on their plantarflexor muscles, and seven nontrained, non-frail older women living at home participated in this study as controls. Participants were asked to perform maximal voluntary contractions (MVC) during isometric plantarflexion in a lying position. Musculo-tendinous (MT) stiffness was assessed before and after the NMES training by measuring the displacement of the MT junction and related tendon force during MVC. In a standing position, the limit of stability (LoS) performance was determined through the maximal forward displacement of the center of foot pressure, and related postural sway parameters were computed around the LoS time gap, a high force requiring task. The NMES training induced an increase in MVC, MT stiffness, and LoS. It significantly changed the dynamics of postural balance as a function of the tendon property changes. The study outcomes, together with a multivariate analysis of investigated variables, highlighted the benefits of NMES as a potential tool in combating neuromuscular weakening in the elderly. The presented training-based strategy is valuable in alleviating some of the adverse functional consequences of aging by directly acting on intrinsic biomechanical and muscular properties whose improvements are immediately transferable into a functional context.

  16. Lead exposure in Latin America and the Caribbean. Lead Research Group of the Pan-American Health Organization.

    PubMed Central

    Romieu, I; Lacasana, M; McConnell, R

    1997-01-01

    As a result of the rapid industrialization of Latin America and the Caribbean during the second half of this century, exposure to lead has become an increasingly important problem. To obtain an estimate of the magnitude of lead exposure in the region, we carried out a survey and a literature search on potential sources of lead exposure and on blood lead concentrations. Sixteen out of 18 Latin American and 2 out of 10 Caribbean countries responded to the survey. Lead in gasoline remains a major problem, although the lead content has decreased in many countries in the last few years. The impact of leaded fuel is more important in urban settings, given their high vehicular density. Seventy-five percent of the population of the region lives in urban areas, and children younger than 15 years of age, the most susceptible group, comprise 30% of the population. Other sources of lead exposure identified in the region included industrial emissions, battery recycling, paint and varnishes, and contaminated food and water. Lead is recognized as a priority problem by national authorities in 72% of the countries that responded to the survey, and in 50% of the countries some legislation exists to regulate the lead content in certain products. However, compliance is low. There is an urgent need for a broad-based coalition between policy makers, industry, workers, unions, health care providers, and the community to take actions to reduce environmental and occupational lead exposures in all the Latin American and Caribbean countries. Images Figure 1. Figure 2. PMID:9189704

  17. Lead exposure in Laysan albatross adults and chicks in Hawaii: prevalence, risk factors, and biochemical effects.

    PubMed

    Work, T M; Smith, M R

    1996-07-01

    Prevalence of lead exposure and elevated tissue lead was determined in Laysan albatross (Diomedea immutabilis) in Hawaii. The relationship between lead exposure and proximity to buildings, between elevated blood lead and droopwing status, and elevated liver lead and presence of lead-containing paint chips in the proventriculus in albatross chicks was also examined. Finally, the effects of lead on the enzyme delta-aminolevulinic acid dehydratase (ALAD) was determined. There was a significant association between lead exposure or elevated tissue lead and proximity to buildings in albatross chicks and presence of lead paint chips in the proventriculus and elevated liver lead in carcasses. Although there was a significant association between elevated blood lead and droopwing chicks, there were notable exceptions. Prevalence of elevated tissue lead in albatross chicks was highest on Sand Island Midway and much less so on Kauai and virtually nonexistent in other areas. Prevalence of lead exposure decreased as numbers of buildings to which chicks were exposed on a given island decreased. Laysan albatross adults had minimal to no lead exposure. There was a significant negative correlation between blood lead concentration and ALAD activity in chicks. Based on ALAD activity, 0.03-0.05 microg/ml was the no effect range for blood lead in albatross chicks.

  18. Lead exposure in Laysan albatross adults and chicks in Hawaii: Prevalence, risk factors, and biochemical effects

    USGS Publications Warehouse

    Work, Thierry M.; Smith, M.R.

    1996-01-01

    Prevalence of lead exposure and elevated tissue lead was determined in Laysan albatross (Diomedea immutabilis) in Hawaii. The relationship between lead exposure and proximity to buildings, between elevated blood lead and droopwing status, and elevated liver lead and presence of lead-containing paint chips in the proventriculus in albatross chicks was also examined. Finally, the effects of lead on the enzyme δ-amino-levulinic acid dehydratase (ALAD) was determined. There was a significant association between lead exposure or elevated tissue lead and proximity to buildings in albatross chicks and presence of lead paint chips in the proventriculus and elevated liver lead in carcasses. Although there was a significant association between elevated blood lead and droopwing chicks, there were notable exceptions. Prevalence of elevated tissue lead in albatross chicks was highest on Sand Island Midway and much less so on Kauai and virtually nonexistent in other areas. Prevalence of lead exposure decreased as numbers of buildings to which chicks were exposed on a given island decreased. Laysan albatross adults had minimal to no lead exposure. There was a significant negative correlation between blood lead concentration and ALAD activity in chicks. Based on ALAD activity, 0.03-0.05 μg/ml was the no effect range for blood lead in albatross chicks.

  19. Toxic lead exposure in the urban rock dove

    SciTech Connect

    DeMent, S.H.; Chisolm, J.J. Jr.; Eckhaus, M.A.; Strandberg, J.D.

    1987-04-01

    Thirteen adult urban rock doves (Columba livia), 12 captured alive and one found dead, were studied from the Baltimore zoo. The mean concentration of lead in the blood for the 12 live birds was 184.5 +/- 531.2 (range 10.5-1,870 micrograms/dl). Three of the 13 birds with high measured blood and tissue lead concentrations were found at necropsy with lead shot pellets in their gizzards. Correlations were not found between concentrations of lead in the blood and body weight or hematocrit. Conversely, high correlations were noted between concentrations of lead in the blood and measured liver and kidney concentrations (r = 0.946, P less than 0.01; r = 0.993, P less than 0.01, respectively). Numbers of intranuclear acid-fast inclusions per 10 consecutive fields (100x oil immersion lens) correlated well with measured kidney lead concentrations (r = 0.990, P less than 0.001).

  20. Prenatal Cigarette Exposure and Infant Learning Stimulation as Predictors of Cognitive Control in Childhood

    ERIC Educational Resources Information Center

    Mezzacappa, Enrico; Buckner, John C.; Earls, Felton

    2011-01-01

    Prenatal exposures to neurotoxins and postnatal parenting practices have been shown to independently predict variations in the cognitive development and emotional-behavioral well-being of infants and children. We examined the independent contributions of prenatal cigarette exposure and infant learning stimulation, as well as their…

  1. Prenatal Cigarette Exposure and Infant Learning Stimulation as Predictors of Cognitive Control in Childhood

    ERIC Educational Resources Information Center

    Mezzacappa, Enrico; Buckner, John C.; Earls, Felton

    2011-01-01

    Prenatal exposures to neurotoxins and postnatal parenting practices have been shown to independently predict variations in the cognitive development and emotional-behavioral well-being of infants and children. We examined the independent contributions of prenatal cigarette exposure and infant learning stimulation, as well as their…

  2. Lead in housing paints: an exposure source still not taken seriously for children lead poisoning in China.

    PubMed

    Lin, G Z; Peng, R F; Chen, Q; Wu, Z G; Du, L

    2009-01-01

    After prohibitions on lead gasoline additives, which have proved to be a public health accomplishment world wide, many countries focus on other exposure source of children lead poisoning. Removing lead from paints is one of the important measures. Although there have been regulatory limits on lead in paints in China, evidence reported in this article indicates that lead-based paints were very common in new paints available for housing and in existing residential paints. Twenty-nine of 58 new paint samples (50%) had lead content equal to or exceeding 600 ppm, including 14 (24%) equal to or exceeding 5000 ppm. The highest sample contained 153,000 ppm lead, about 15% of the paint weight. Thirty-two new paints (55%) contained "soluble" lead exceeding 90 ppm, the current lead limit on paints in China. Of the existing paints, 16 of 28 samples of existing paint (57%) collected from 24 kindergartens and primary schools had lead concentrations equal to or exceeding 600 ppm, including six samples (21%) equal to or exceeding 5000 ppm. The highest concentration sample contained 51,800 ppm lead, accounting for 5.2% of the paint weight. It has been shown in many areas that paint lead is a major exposure source for lead poisoning in children. This is particularly true after the phasing out of lead from gasoline. Effective limitation on lead content in new paint, and lead hazard control measures directed towards existing paint, could reduce children blood lead levels (BLLs). There has been a lead standard for paints in China since 1986 and a stricter limit was introduced in recent years. Governments should take it seriously and enforce regulations, commit a long-term challenge to eliminate paint lead as it is the threat to current and the next generation.

  3. An empirical comparison of lead exposure pathway models.

    PubMed Central

    Succop, P; Bornschein, R; Brown, K; Tseng, C Y

    1998-01-01

    Structural equation modeling is a statistical method for partitioning the variance in a set of interrelated multivariate outcomes into that which is due to direct, indirect, and covariate (exogenous) effects. Despite this model's flexibility to handle different experimental designs, postulation of a causal chain among the endogenous variables and the points of influence of the covariates is required. This has motivated the researchers at the University of Cincinnati Department of Environmental Health to be guided by a theoretical model for movement of lead from distal sources (exterior soil or dust and paint lead) to proximal sources (interior dust lead) and then finally to biologic outcomes (handwipe and blood lead). The question of whether a single structural equation model built from proximity arguments can be applied to diverse populations observed in different communities with varying lead amounts, sources, and bioavailabilities is addressed in this article. This reanalysis involved data from 1855 children less than 72 months of age enrolled in 11 studies performed over approximately 15 years. Data from children residing near former ore-processing sites were included in this reanalysis. A single model adequately fit the data from these 11 studies; however, the model needs to be flexible to include pathways that are not frequently observed. As expected, the more proximal sources of interior dust lead and handwipe lead were the most important predictors of blood lead; soil lead often had a number of indirect influences. A limited number of covariates were also isolated as usually affecting the endogenous lead variables. The blood lead levels surveyed at the ore-processing sites were comparable to and actually somewhat lower than those reported in the the Third National Health and Nutrition Examination Survey. Lessened bioavailability of the lead at certain of these sites is a probable reason for this finding. PMID:9860917

  4. Pediatric lead exposure and the water crisis in Flint, Michigan.

    PubMed

    DeWitt, Rachel D

    2017-02-01

    Changing the source of the water supply to save money had the unintended consequence of exposing residents of Flint, Mich., to elevated lead levels in their drinking water. A study done at Flint's Hurley Children's Hospital demonstrated that the incidence of elevated blood lead levels of children living in the affected area nearly doubled after the change in the water source. This article reviews the recommendations for lead screening and for reporting, following, and treating children with blood lead levels greater than 5 mcg/dL.

  5. Childhood Lead Exposure After the Phaseout of Leaded Gasoline: An Ecological Study of School-Age Children in Kampala, Uganda

    PubMed Central

    Graber, Lauren K.; Asher, Daniel; Anandaraja, Natasha; Bopp, Richard F.; Merrill, Karen; Cullen, Mark R.; Luboga, Samuel; Trasande, Leonardo

    2010-01-01

    Background Tetraethyl lead was phased out of gasoline in Uganda in 2005. Recent mitigation of an important source of lead exposure suggests examination and re-evaluation of the prevalence of childhood lead poisoning in this country. Ongoing concerns persist about exposure from the Kiteezi landfill in Kampala, the country’s capital. Objectives We determined blood lead distributions among Kampala schoolchildren and identified risk factors for elevated blood lead levels (EBLLs; ≥ 10 μg/dL). Analytical approach Using a stratified, cross-sectional design, we obtained blood samples, questionnaire data, and soil and dust samples from the homes and schools of 163 4- to 8-year-old children representing communities with different risks of exposure. Results The mean blood lead level (BLL) was 7.15 μg/dL; 20.5% of the children were found to have EBLL. Multivariable analysis found participants whose families owned fewer household items, ate canned food, or used the community water supply as their primary water source to have higher BLLs and likelihood of EBLLs. Distance < 0.5 mi from the landfill was the factor most strongly associated with increments in BLL (5.51 μg/dL, p < 0.0001) and likelihood of EBLL (OR = 4.71, p = 0.0093). Dust/soil lead was not significantly predictive of BLL/EBLL. Conclusions Lead poisoning remains highly prevalent among school-age children in Kampala. Confirmatory studies are needed, but further efforts are indicated to limit lead exposure from the landfill, whether through water contamination or through another mechanism. Although African nations are to be lauded for the removal of lead from gasoline, this study serves as a reminder that other sources of exposure to this potent neurotoxicant merit ongoing attention. PMID:20194080

  6. Multicolumn spinal cord stimulation lead implantation using an optic transligamentar minimally invasive technique.

    PubMed

    Rigoard, Philippe; Luong, Anh Tran; Delmotte, Alexandre; Raaholt, Mille; Roulaud, Manuel; Monlezun, Olivier; Triphose, Audrey; Guetarni, Farid; Brugière, Benjamin; Misbert, Lorraine; Diallo, Bakari; Bataille, Benoit

    2013-09-01

    A new generation of neurostimulation surgical leads is used to increase the success of spinal cord stimulation in difficult-to-treat indications such as failed back surgery syndrome. Minimal access spinal technologies (MASTs) have previously been used for surgical lead implantation. However, only a unilateral approach was possible, causing difficulties for median lead placement, and not always preventing laminectomy. A recent MAST technique was used to implant spinal cord stimulation leads without these limitations. To describe the MAST technique used in a pilot study. Twenty-four consecutive patients were implanted with a multicolumn surgical lead for refractory chronic back and leg pain by using the optic transligamentar MAST technique. The MAST technique allowed median lead placement, facilitated visualization of the spine, and permitted transligamentar insertion that minimized scarring and muscle damage. No technique-related adverse events or lead revisions were reported. Use of a MAST approach could be useful in safe implantation of multicolumn surgical leads in difficult-to-treat, refractory lower back pain conditions such as failed back surgery syndrome.

  7. [Lead exposure in the ceramic tile industry: time trends and current exposure levels].

    PubMed

    Candela, S; Ferri, F; Olmi, M

    1998-01-01

    There is a high density of industries for the production of ceramic tiles in the District of Scandiano (province of Reggio Emilia, Emilia Romagna region). In this area, since the beginning of 1970s, the time trend of Pb exposure in ceramic tile plants has been evaluated by means of biological monitoring (BM) data collected at the Service of Prevention and Safety in the Work Environment and its associated Toxicology Laboratory. From these data, a clear decreasing time trend of exposure levels is documented, the reduction being more evident during the seventies and in 1985-88. During the seventies BM was introduced systematically in all ceramic tile plants with the determination of delta-aminolevulinic acid in urine (ALA-U). As a consequence of the BM programme, hygienic measures for the abatement of pollution inside the plants were implemented, and a reduction, from 20.6% to 2%, of ALA-U values exceeding 10 mg/l, was observed. In 1985, the determination of lead in blood (PbB) replaced that of ALA-U in the BM programmes and highlighted the persistence of high level of exposure to Pb, which could not be outlined by means of ALA-U because of its lower sensitivity. PbB levels were 36.1 micrograms/100 ml and 25.7 micrograms/100 ml in male and female workers, respectively. These results required the implementation, within the plants, of additional hygienic measures and a significant reduction of PbB was obtained in the following three years. In 1988 PbB levels were 26.0 +/- 10.7 and 21.6 +/- 10.3 micrograms/100 ml in male and female workers, respectively. In 1993-95 Pb levels were obtained from 1328 male and 771 female workers of 56 plants, accounting for about 40% of the total number of workers in the ceramic industry, in the zones of Sassuolo and Scandiano. Exposure levels are not different from those observed in the preceding years, with PbB levels of 25.3 +/- 11.1 and 19.1 +/- 9.2 micrograms/100 ml in male and female workers, respectively.

  8. Relationship of biological indices of lead exposure to the health status of workers in a secondary lead smelter

    SciTech Connect

    Hammond, P.B.; Lerner, S.I.; Gartside, P.S.; Hanenson, I.B.; Roda, S.B.; Foulkes, E.C.; Johnson, D.R.; Pesce, A.J.

    1980-07-01

    The fidelity with which common indices of lead exposure correlate with renal and hematopoietic function and with frequency of symptoms was studied. The subjects were men working in a secondary lead smelter. Among several indices of renal function, only serum urea nitrogen (SUN) was consistely correlated with any of the indices of lead exposure. The concentration of lead in blood (PbB), the rate of urinary excretion of lead (PbU) and of delta aminolevulinic acid in the urine (ALAU) correlated with SUN. By contrast, erythrocytic porphyrin concentration (EP) did not correlate with SUN. Similarly, the frequency of occurrence of symptoms correlated well with PbB and ALAU but did not correlate with EP. All of the above indices of lead exposure, with the exception of PbU, correlated well with hemoglobin (Hb) status. In summary, these results suggest that PbB rather than EP is the best single exposure index for biological monitoring of lead workers. This measurement should be supplemented by periodic determination of SUN and Hb.

  9. Removal of Vagus Nerve Stimulator Leads and Reuse of Same Site for Reimplantation: Technique and Experience.

    PubMed

    Kumar, Ramesh; Winston, Ken R; Folzenlogen, Zach

    2016-07-01

    This report describes the authors' experience and technique in removing vagus nerve stimulator leads, including coils, and reuse of the same site on the vagus nerve for implantation of new coils. The charts of all patients who underwent complete removal by the authors of vagus nerve stimulator leads between 1 September 2001 and 1 July 2015 were retrospectively reviewed. Thirty patients underwent 31 surgeries for removal of vagus nerve stimulator leads. Complete removal, including proximal coils around the vagus nerve, was achieved in all cases. Reimplantation was performed immediately at the same location in 24 patients, delayed in 1 patient, and never replaced in 6. Long-term vocal cord paralysis followed 2 of 9 surgeries performed with sharp dissection and followed one of 22 surgeries in which dissection was performed with monopolar microneedle electrocautery. Vagus nerve stimulator coils can be removed from the vagus nerve, via monopolar microneedle electrocautery, and the same site reused for immediate reimplantation with relative safety. Copyright © 2016 Elsevier Inc. All rights reserved.

  10. Inequitable Chronic Lead Exposure: A Dual Legacy of Social and Environmental Injustice.

    PubMed

    Leech, Tamara G J; Adams, Elizabeth A; Weathers, Tess D; Staten, Lisa K; Filippelli, Gabriel M

    2016-01-01

    Both historic and contemporary factors contribute to the current unequal distribution of lead in urban environments and the disproportionate impact lead exposure has on the health and well-being of low-income minority communities. We consider the enduring impact of lead through the lens of environmental justice, taking into account well-documented geographic concentrations of lead, legacy sources that produce chronic exposures, and intergenerational transfers of risk. We discuss the most promising type of public health action to address inequitable lead exposure and uptake: primordial prevention efforts that address the most fundamental causes of diseases by intervening in structural and systemic inequalities.

  11. Childhood lead exposure in France: benefit estimation and partial cost-benefit analysis of lead hazard control

    PubMed Central

    2011-01-01

    Background Lead exposure remains a public health concern due to its serious adverse effects, such as cognitive and behavioral impairment: children younger than six years of age being the most vulnerable population. In Europe, the lead-related economic impacts have not been examined in detail. We estimate the annual costs in France due to childhood exposure and, through a cost benefit analysis (CBA), aim to assess the expected social and economic benefits of exposure abatement. Methods Monetary benefits were assessed in terms of avoided national costs. We used results from a 2008 survey on blood-lead (B-Pb) concentrations in French children aged one to six years old. Given the absence of a threshold concentration being established, we performed a sensitivity analysis assuming different hypothetical threshold values for toxicity above 15 μg/L, 24 μg/L and 100 μg/L. Adverse health outcomes of lead exposure were translated into social burden and economic costs based on literature data from literature. Direct health benefits, social benefits and intangible avoided costs were included. Costs of pollutant exposure control were partially estimated in regard to homes lead-based paint decontamination, investments aiming at reducing industrial lead emissions and removal of all lead drinking water pipes. Results The following overall annual benefits for the three hypothetical thresholds values in 2008 are: €22.72 billion, €10.72 billion and €0.44 billion, respectively. Costs from abatement ranged from €0.9 billion to 2.95 billion/year. Finally, from a partial CBA of lead control in soils and dust the estimates of total net benefits were € 3.78 billion, € 1.88 billion and €0.25 billion respectively for the three hypothesized B-Pb effect values. Conclusions Prevention of childhood lead exposure has a high social benefit, due to reduction of B-Pb concentrations to levels below 15 μg/L or 24 μg/L, respectively. Reducing only exposures above 100 μg/L B-Pb has

  12. Lead exposure and recovery rates of black ducks banded in Tennessee

    USGS Publications Warehouse

    Samuel, Michael D.; Bowers, E. Frank; Franson, J. Christian

    1992-01-01

    American black ducks (Anas rubripes) wintering in Tennessee during 1986 to 1988 were tested for exposure to lead. Twelve percent of the birds had blood lead concentrations exceeding 0.2 ppm. Significant differences in the prevalence of lead exposure were found for adults (14.4%) and juveniles (8.2%). Exposed birds had higher blood lead concentrations at one study site, corresponding with a lower survival index.

  13. An evaluation of worker lead exposures and cleaning effectiveness during removal of deteriorated lead-based paint.

    PubMed

    Sussell, A; Hart, C; Wild, D; Ashley, K

    1999-03-01

    We evaluated worker lead exposures and cleaning effectiveness during initial cleanup of 19th-century buildings with highly deteriorated lead-based paint. Eighteen rooms of similar size and condition in two university-owned buildings were selected for a pilot project to compare three methods for removing loose paint, paint chips, and dust. The methods used were: dry scraping followed by dry sweeping (no engineering or work practice controls); wet scraping and high-efficiency particulate air (HEPA) vacuuming; and the latter method with the addition of a portable HEPA-filtered exhaust fan in the room providing about 40 air changes per hour. The final step for all methods was wet-mopping once with tri-sodium phosphate solution. During a single day 18 rooms were cleaned; each of three two-person work crews cleaned six rooms, two with each method. Air and surface samples were collected before, during, and after cleaning. All of the methods were potentially hazardous to workers: 44 percent of the method-based exposures (range: 5.0-360 micrograms/m3) and one of five full-shift exposures exceeded the OSHA PEL (range 9.4-110 micrograms/m3). Lowest worker exposures were during the wet scraping and vacuuming method (mean: 24 micrograms/m3). Providing general ventilation in rooms did not reduce worker exposures and appeared to increase them (mean: 73 micrograms/m3). Overall, the mean floor surface lead levels were reduced 50 percent after cleaning (from 2,600 to 1,300 micrograms/ft2), but the effectiveness of the three methods in reducing floor lead levels did not differ significantly. Overall, the method, mean paint lead concentration, pre-cleaning surface lead concentration, and work crew were significantly associated with the mean worker exposures during cleaning (p = 0.023), but not with the post-cleaning surface lead concentrations (p = 0.13).

  14. Neurodevelopment in Early Childhood Affected by Prenatal Lead Exposure and Iron Intake.

    PubMed

    Shah-Kulkarni, Surabhi; Ha, Mina; Kim, Byung-Mi; Kim, Eunjeong; Hong, Yun-Chul; Park, Hyesook; Kim, Yangho; Kim, Bung-Nyun; Chang, Namsoo; Oh, Se-Young; Kim, Young Ju; Kimʼs, Young Ju; Lee, Boeun; Ha, Eun-Hee

    2016-01-01

    No safe threshold level of lead exposure in children has been recognized. Also, the information on shielding effect of maternal dietary iron intake during pregnancy on the adverse effects of prenatal lead exposure on children's postnatal neurocognitive development is very limited. We examined the association of prenatal lead exposure and neurodevelopment in children at 6, 12, 24, and 36 months and the protective action of maternal dietary iron intake against the impact of lead exposure. The study participants comprise 965 pregnant women and their subsequent offspring of the total participants enrolled in the Mothers and Children's environmental health study: a prospective birth cohort study. Generalized linear model and linear mixed model analysis were performed to analyze the effect of prenatal lead exposure and mother's dietary iron intake on children's cognitive development at 6, 12, 24, and 36 months. Maternal late pregnancy lead was marginally associated with deficits in mental development index (MDI) of children at 6 months. Mothers having less than 75th percentile of dietary iron intake during pregnancy showed significant increase in the harmful effect of late pregnancy lead exposure on MDI at 6 months. Linear mixed model analyses showed the significant detrimental effect of prenatal lead exposure in late pregnancy on cognitive development up to 36 months in children of mothers having less dietary iron intake during pregnancy. Thus, our findings imply importance to reduce prenatal lead exposure and have adequate iron intake for better neurodevelopment in children.

  15. Uses and limits of empirical data in measuring and modeling human lead exposure.

    PubMed Central

    Mushak, P

    1998-01-01

    This paper examines the uses and limits of empirical data in evaluating measurement and modeling approaches to human lead exposure. Empirical data from experiment or observation or both have been used in studies of lead exposure. For example, experimental studies have elucidated and quantified physiologic or biokinetic parameters of lead exposure under controlled conditions. Observation, i.e., epidemiology, has been widely applied to study population exposures to lead. There is growing interest in the use of lead exposure prediction models and their evaluation before use in risk assessment. Empirical studies of lead exposure must be fully understood, especially their limits, before they are applied as "standards" or reference information for evaluation of exposure models, especially the U.S. Environmental Protection Agency's lead biokinetic model that is a focus of this article. Empirical and modeled datasets for lead exposure may not agree due to a) problems with the observational data or b) problems with the model; caution should be exercised before either a model or observational data are rejected. There are at least three sources of discordance in cases where there is lack of agreement: a) empirical data are accurate but the model is flawed; b) the model is valid but reference empirical data are inaccurate; or c) neither empirical data nor model is accurate, and each is inaccurate in different ways. This paper evaluates some of the critical empirical input to biokinetic models, especially lead bioavailability. Images Figure 3 PMID:9860906

  16. Correlation between biochemical indicators of lead exposure and semen quality in a lead-poisoned firearms instructor

    SciTech Connect

    Fisher-Fischbein, J.; Fischbein, A.; Melnick, H.D.; Bardin, C.W.

    1987-02-13

    Lead poisoning is a disease of great public health concern, particularly because of the hazards that lead can pose to children as a result of ingestion of lead-based paint and perhaps as a consequence of the effects of lead pollution of the ambient air. However, lead poisoning is also a common occupational disease among adults. Persons who work as instructors at indoor firing ranges are likewise at high risk for occupational lead poisoning. The typical biochemical features of lead poisoning include inhibition of heme synthesis manifested by elevated levels of erythrocyte protoporphyrin and decreased activity of sigma-aminolevulinic acid dehydratase. Reproductive effects of lead have been reported in both men and women, but these effects rarely present themselves as practical clinical problems in occupational medicine practice. The current Department of Labor standard for occupational exposure to inorganic lead has been promulgated with special emphasis on the protection of the worker from damage to the reproductive system. The authors had the opportunity of measuring biologic indicators of lead exposure and of assessing semen quality in a firearms instructor with lead poisoning and infertility, who was treated and who fathered a child. They report herein the results of these longitudinal observations.

  17. Understanding international crime trends: the legacy of preschool lead exposure.

    PubMed

    Nevin, Rick

    2007-07-01

    This study shows a very strong association between preschool blood lead and subsequent crime rate trends over several decades in the USA, Britain, Canada, France, Australia, Finland, Italy, West Germany, and New Zealand. The relationship is characterized by best-fit lags (highest R2 and t-value for blood lead) consistent with neurobehavioral damage in the first year of life and the peak age of offending for index crime, burglary, and violent crime. The impact of blood lead is also evident in age-specific arrest and incarceration trends. Regression analysis of average 1985-1994 murder rates across USA cities suggests that murder could be especially associated with more severe cases of childhood lead poisoning.

  18. Can realtor education reduce lead exposures for vulnerable populations?

    PubMed

    Phoenix, Janet A; Green, Rodney D; Thompson, Aisha M

    2013-01-01

    Lead is known for its devastating effects on people, particularly children under the age of six. Disturbed lead paint in homes is the most common source of lead poisoning of children. Preventive approaches including consumer education on the demand side of the housing market (purchasers and renters of housing units) and disclosure regulations on supply side of the housing market (landlords, homeowners, developers, and licensed realtors) have had mixed outcomes. The study described in this article considered whether a novel supply-side intervention that educates licensed real estate agents about the specific dangers of lead poisoning would result in better knowledge of lead hazards and improved behavior with respect to the information they convey to potential home buyers. Ninety-one licensed realtors were trained for four hours on lead hazards and their health impacts. Pre- and postsurveys and a six-month follow-up interview were conducted to assess the impact of the intervention on their knowledge and self-reported behaviors with clients. The findings suggest that supply-side education could have a salutary impact on realtor knowledge and behavior.

  19. Evaluation of preventive and control measures for lead exposure in a South African lead-acid battery recycling smelter.

    PubMed

    Dyosi, Sindiswa

    2007-10-01

    In South Africa, new lead regulations released in February 2002 served as motivation for a cross-sectional study investigating the effectiveness of preventive and control measures implemented in a lead smelter that recycles lead-acid batteries. Twenty-two workers were observed and interviewed. Structured questionnaires were used to gather workers' personal information, perception about their work environment, health risks, and work practices. Retrospective data from air monitoring and medical surveillance programs were obtained from the plant's records. The smelter implemented a number of control measures for lead exposure, including engineering controls, administrative controls, and, as a last resort, personal protective equipment. Engineering controls were rated the best control measure and included local exhaust ventilation systems and wet methods. Positive pressure systems were used in the offices and laboratory. The local exhaust ventilation system was rated the best engineering control measure. Although control measures were used, areas such as smelting and refinery had average lead in air levels above 0.15 mg/m(3), the occupational exposure limit for lead. This was a concern especially with regard to the smelting area because those workers had the second highest mean blood lead levels; workers in the battery breaking area had the highest. Regular use of personal protective equipment by some workers in the "lead exposure zones" was not observed. Although the mean blood lead levels had been below 40 micro g/dL for more than 90% of the workers since 2001, more than 70% of workers reported concerns about their health while working in the smelter. Even though control measures were implemented, they were not adequate because in some areas lead in air exceeded the occupational exposure limit. Therefore, improvement of existing measures and regular monitoring of personal protective equipment use were included in the recommendations given to the smelter.

  20. Prenatal lead exposure and relationship with maternal exposure determinants in a public maternity hospital of La Plata, Argentina.

    PubMed

    Martins, Enrique; Varea, Ana; Apezteguía, María; González, Horacio F; Girardelli, Ana; Caro, Laura Sanchez; Lobisuto, Mario; Delgado, Griselda; Disalvo, Liliana

    2014-03-01

    Prenatal lead exposure is a health hazard that may cause cognitive development impairments and other adverse effects in children. We conducted a cross sectional study analyzing cord blood lead levels (CBLL) of newborns and their relationship with maternal determinants of lead exposure. Mothers answered a questionnaire about socio-demographic, lifestyle habits and environmental characteristics. We used Mann-Whitney's test to compare CBLL geometrical means (GM) corresponding to the presence or absence of each lead exposure determinant, and Chi square test to study the relationship between CBLL and maternal lead exposure determinants. A total of 159 newborns participated in the study. CBLL GM was 2.1 μg/dL; and 25% of the participants had a measurable CBLL (LOQ=3.3 μg/dl). Although the participants had several determinants of lead exposure, we only found a significant relationship with inside household determinants, such as presence of lead piping (p=0.026), unplastered walls (p=0.046) and peeling paint (p=0.048). Our results show that CBLL GM was similar to that reported in several studies conducted around the world. However, 25% of the participants might have some degree of risk for lead poisoning.

  1. Investigation into Deep Brain Stimulation Lead Designs: A Patient-Specific Simulation Study

    PubMed Central

    Alonso, Fabiola; Latorre, Malcolm A.; Göransson, Nathanael; Zsigmond, Peter; Wårdell, Karin

    2016-01-01

    New deep brain stimulation (DBS) electrode designs offer operation in voltage and current mode and capability to steer the electric field (EF). The aim of the study was to compare the EF distributions of four DBS leads at equivalent amplitudes (3 V and 3.4 mA). Finite element method (FEM) simulations (n = 38) around cylindrical contacts (leads 3389, 6148) or equivalent contact configurations (leads 6180, SureStim1) were performed using homogeneous and patient-specific (heterogeneous) brain tissue models. Steering effects of 6180 and SureStim1 were compared with symmetric stimulation fields. To make relative comparisons between simulations, an EF isolevel of 0.2 V/mm was chosen based on neuron model simulations (n = 832) applied before EF visualization and comparisons. The simulations show that the EF distribution is largely influenced by the heterogeneity of the tissue, and the operating mode. Equivalent contact configurations result in similar EF distributions. In steering configurations, larger EF volumes were achieved in current mode using equivalent amplitudes. The methodology was demonstrated in a patient-specific simulation around the zona incerta and a “virtual” ventral intermediate nucleus target. In conclusion, lead design differences are enhanced when using patient-specific tissue models and current stimulation mode. PMID:27618109

  2. Long-term human exposure to lead from different media and intake pathways.

    PubMed

    Pizzol, Massimo; Thomsen, Marianne; Andersen, Mikael Skou

    2010-10-15

    Lead (Pb) is well known as an environmental pollutant: it can accumulate in various media, so actual lead exposure reflects both historical and present contaminations. Two main challenges then emerge: obtaining updated information to gain an overall picture of the sources of exposure, and predicting the resulting internal body exposure levels and effects that occur under long-term exposure conditions. In this paper, a modeling approach is used to meet these challenges with reference to Danish exposure conditions. Levels of lead content in various media have been coupled with data for lead intake and absorption in the human body, for both children and adults. An age-dependent biokinetic model allows then for determination of the blood lead levels resulting from chronic exposure. The study shows that the actual intake of lead is up to 27% of the Provisional Tolerable Daily Intake (PTDI) for children and around 8% for adults. It is confirmed that the critical route of exposure is via ingestion, accounting for 99% of total lead intake, while inhalation contributes only to 1% of total lead intake. The resulting lead levels in the blood after 2 years of exposure to actual contamination conditions have been estimated as up to 2.2μg/dl in children and almost 1μg/dl in adults. Impacts from lead can occur even at such levels. The role of historical and present sources to lead in the environment is discussed, and, for specific child and adult exposure scenarios, external-internal concentration relationships for the direct linkage between lead in environmental media and resulting concentrations of lead in blood are then presented. Copyright © 2010 Elsevier B.V. All rights reserved.

  3. Implications of new data on lead toxicity for managing and preventing exposure.

    PubMed Central

    Silbergeld, E K

    1990-01-01

    Recent advances in research on low-level lead poisoning point to the need to increase efforts to prevent exposure. Current biomedical consensus accepts that blood lead levels as low as 5 to 15 mcg/dL are risky to fetuses, young children, and adults. Lead at low dose is associated with increased blood pressure in adults, and chronic exposure has been associated in cohort studies with kidney disease and cancer. Data on lead toxicokinetics also points to the hazards of low-level, chronic exposure, since the lead that is accumulated over time in bone can be released at a relatively rapid rate during pregnancy and menopause. Sources that contribute to current lead exposure of the general population include unabated lead-based paint and contaminated soils, as well as lower level but pervasive sources in drinking water, food, and consumer products. PMID:2088754

  4. Implications of new data on lead toxicity for managing and preventing exposure

    SciTech Connect

    Silbergeld, E.K. )

    1990-11-01

    Recent advances in research on low-level lead poisoning point to the need to increase efforts to prevent exposure. Current biomedical consensus accepts that blood lead levels as low as 5 to 15 mcg/dL are risky to fetuses, young children, and adults. Lead at low dose is associated with increased blood pressure in adults, and chronic exposure has been associated in cohort studies with kidney disease and cancer. Data on lead toxicokinetics also points to the hazards of low-level, chronic exposure, since the lead that is accumulated over time in bone can be released at a relatively rapid rate during pregnancy and menopause. Sources that contribute to current lead exposure of the general population include unabated lead-based paint and contaminated soils, as well as lower level but pervasive sources in drinking water, food, and consumer products.

  5. Coordinate-based lead location does not predict Parkinson's disease deep brain stimulation outcome.

    PubMed

    Nestor, Kelsey A; Jones, Jacob D; Butson, Christopher R; Morishita, Takashi; Jacobson, Charles E; Peace, David A; Chen, Dennis; Foote, Kelly D; Okun, Michael S

    2014-01-01

    Effective target regions for deep brain stimulation (DBS) in Parkinson's disease (PD) have been well characterized. We sought to study whether the measured Cartesian coordinates of an implanted DBS lead are predictive of motor outcome(s). We tested the hypothesis that the position and trajectory of the DBS lead relative to the mid-commissural point (MCP) are significant predictors of clinical outcomes. We expected that due to neuroanatomical variation among individuals, a simple measure of the position of the DBS lead relative to MCP (commonly used in clinical practice) may not be a reliable predictor of clinical outcomes when utilized alone. 55 PD subjects implanted with subthalamic nucleus (STN) DBS and 41 subjects implanted with globus pallidus internus (GPi) DBS were included. Lead locations in AC-PC space (x, y, z coordinates of the active contact and sagittal and coronal entry angles) measured on high-resolution CT-MRI fused images, and motor outcomes (Unified Parkinson's Disease Rating Scale) were analyzed to confirm or refute a correlation between coordinate-based lead locations and DBS motor outcomes. Coordinate-based lead locations were not a significant predictor of change in UPDRS III motor scores when comparing pre- versus post-operative values. The only potentially significant individual predictor of change in UPDRS motor scores was the antero-posterior coordinate of the GPi lead (more anterior lead locations resulted in a worse outcome), but this was only a statistical trend (p<.082). The results of the study showed that a simple measure of the position of the DBS lead relative to the MCP is not significantly correlated with PD motor outcomes, presumably because this method fails to account for individual neuroanatomical variability. However, there is broad agreement that motor outcomes depend strongly on lead location. The results suggest the need for more detailed identification of stimulation location relative to anatomical targets.

  6. Australia's leading public health body delays action on the revision of the public health goal for blood lead exposures.

    PubMed

    Taylor, Mark Patrick; Winder, Chris; Lanphear, Bruce P

    2014-09-01

    Globally, childhood blood lead levels have fallen precipitously in developed countries since the 1970s following action by international bodies such as the WHO and Food and Agricultural Organization (FAO) of the United Nations. These reductions have been affected by the activities of national agencies such as the US EPA and US Centers for Disease Control and Prevention in the establishment of air lead and blood lead standards, the introduction of legislation to remove lead from petrol, paint and consumer products and tighter restrictions on lead emissions. The outcome of recent major international reviews of research into the effects of low-level lead exposures (e.g. by WHO, USA health and environmental agencies, German and Canadian health bodies) has resulted in recommendations to reduce and eliminate lead exposures. By contrast, Australian policy responses to the incontrovertible evidence that adverse neurocognitive and behavioural effects that occur at levels well below the current national goal of 10μg/dL have stalled. The delayed response by Australia occurs at a time when blood lead levels in two of Australia's three primary lead mining and smelting cities: Port Pirie, South Australia and Broken Hill, New South Wales, are rising. In the third city, Mount Isa, Queensland, there is still no systematic, annual testing of childhood blood lead values. This is despite the fact that Mount Isa has the highest lead (and other toxic metals such as cadmium and arsenic) emissions to the environment (120tonnes of lead in 2011/12) from any single point source in Australia. It is clear that both state and national policy approaches to the ongoing risks of lead exposure need to be revised urgently and in line with contemporary international standards. Recommended changes should include a new lower blood lead intervention level of no more than 5μg/dL, with a national goal for all children under 5years of age to have a blood lead level of below 1μg/dL by 2020. In order to

  7. Lead shot contribution to blood lead of First Nations people: the use of lead isotopes to identify the source of exposure.

    PubMed

    Tsuji, Leonard J S; Wainman, Bruce C; Martin, Ian D; Sutherland, Celine; Weber, Jean-Philippe; Dumas, Pierre; Nieboer, Evert

    2008-11-01

    Although lead isotope ratios have been used to identify lead ammunition (lead shotshell pellets and bullets) as a source of exposure for First Nations people of Canada, the actual source of lead exposure needs to be further clarified. Whole blood samples for First Nations people of Ontario, Canada, were collected from participants prior to the traditional spring harvest of water birds, as well as post-harvest. Blood-lead levels and stable lead isotope ratios prior to, and after the harvest were determined by ICP-MS. Data were analyzed by paired t-tests and Wilcoxon Signed-Ranks tests. All participants consumed water birds harvested with lead shotshell during the period of study. For the group excluding six males who were potentially exposed to other sources of lead (as revealed through a questionnaire), paired t-tests and Wilcoxon Signed-Ranks tests showed consistent results: significant (p<0.05) increases in blood-lead concentrations and blood levels of (206)Pb/(204)Pb and (206)Pb/(207)Pb towards the mean values we previously reported for lead shotshell pellets; and a significant decrease in (208)Pb/(206)Pb values towards the mean for lead shotshell pellets. However, when we categorized the group further into a group that did not use firearms and did not eat any other traditional foods harvested with lead ammunition other than waterfowl, our predictions for (206)Pb/(204)Pb, (206)Pb/(207)Pb and (208)Pb/(206)Pb hold true, but there was not a significant increase in blood-lead level after the hunt. It appears that the activity of hunting (i.e., use of a shotgun) was also an important route of lead exposure. The banning of lead shotshell for all game hunting would eliminate a source of environmental lead for all people who use firearms and/or eat wild game.

  8. Lead exposure in American black ducks after implementation of non-toxic shot

    USGS Publications Warehouse

    Samuel, M.D.; Bowers, E. Frank

    2000-01-01

    Lead poisoning from the ingestion of spent shotgun pellets has been recognized as an important disease of North American waterfowl since Bellrose's (1959) research >40 years ago. Nation-wide regulations banning the use of lead shot for waterfowl hunting were established in 1991. We compared the prevalence of lead exposure in American black ducks (Anas rubripes) wintering on 2 areas in Tennessee before (1986-88) and after the ban (1997-99) to assess the effect of the ban on lead shot on this species. Prevalence of elevated blood lead in black ducks declined by 44% from before (11.7% prevalence) to after (6.5% prevalence) the implementation of non-toxic shot. The reduction in lead exposure was pronounced in adult black ducks (from 14.3% to 5.3%). However, prevalence in lead exposure remained similar in juvenile black ducks (from 8.2% to 8.3%). Additional evidence from lead ingestion and lead poisoning mortality events also indicates that lead exposure has declined in waterfowl in the Mississippi flyway. We believe that lead ingestion will continue to decline, despite the persistence of lead shot in some wetlands. The impact of reduced lead exposure on waterfowl populations needs to be assessed.

  9. High-dose allergen exposure leads to tolerance.

    PubMed

    Woodfolk, Judith A

    2005-02-01

    Reports of decreased sensitization to cat allergen (Fel d 1) among individuals living with a cat or subjects exposed to high-dose cat allergen may be explained by the development of a form of high-dose tolerance resulting from natural exposure to an inhalant allergen. Although the epidemiological data regarding the relationship between exposure and sensitization to Fel d 1 are conflicting, the ability for high-dose Fel d 1 to induce a characteristic nonallergic immune response with a distinctive serum antibody profile has been established. Definition of this modified T-helper (Th)2 response to cat allergen, coupled with the renewed interest in regulatory T cells within the immunology field, has provided an avenue for exploring the mechanism by which IgE antibody-mediated responses are controlled. There is mounting evidence to suggest that the modified Th2 response is a variation of the allergic response and that the modified Th2-allergic axis is influenced by allergen dose and genetics. This article discusses putative immune mechanisms of tolerance within the context of an allergen-specific system. The relevance of high-dose allergen exposure and alternate factors such as endotoxin to the development of tolerance is considered. Fel d 1 exhibits unique molecular and immunological characteristics that may contribute to its tolerogenic properties. Major T-cell epitopes of Fel d 1 that preferentially induce regulatory factors have been defined. Furthermore, high-titer IgE antibody responses associated with atopic dermatitis are characterized by a defect in the T-cell repertoire that is specific to these epitopes. Identification of Fel d 1 epitopes that induce interleukin-10 may provide new targets for treatment.

  10. Impact of robotics and a suspended lead suit on physician radiation exposure during percutaneous coronary intervention.

    PubMed

    Madder, Ryan D; VanOosterhout, Stacie; Mulder, Abbey; Elmore, Matthew; Campbell, Jessica; Borgman, Andrew; Parker, Jessica; Wohns, David

    Reports of left-sided brain malignancies among interventional cardiologists have heightened concerns regarding physician radiation exposure. This study evaluated the impact of a suspended lead suit and robotic system on physician radiation exposure during percutaneous coronary intervention (PCI). Real-time radiation exposure data were prospectively collected from dosimeters worn by operating physicians at the head- and chest-level during consecutive PCI cases. Exposures were compared in three study groups: 1) manual PCI performed with traditional lead apparel; 2) manual PCI performed using suspended lead; and 3) robotic PCI performed in combination with suspended lead. Among 336 cases (86.6% manual, 13.4% robotic) performed over 30weeks, use of suspended lead during manual PCI was associated with significantly less radiation exposure to the chest and head of operating physicians than traditional lead apparel (chest: 0.0 [0.1] μSv vs 0.4 [4.0] μSv, p<0.001; head: 0.5 [1.9] μSv vs 14.9 [51.5] μSv, p<0.001). Chest-level radiation exposure during robotic PCI performed in combination with suspended lead was 0.0 [0.0] μSv, which was significantly less chest exposure than manual PCI performed with traditional lead (p<0.001) or suspended lead (p=0.046). In robotic PCI the median head-level exposure was 0.1 [0.2] μSv, which was 99.3% less than manual PCI performed with traditional lead (p<0.001) and 80.0% less than manual PCI performed with suspended lead (p<0.001). Utilization of suspended lead and robotics were observed to result in significantly less radiation exposure to the chest and head of operating physicians during PCI. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Stimulation of TRPC5 cationic channels by low micromolar concentrations of lead ions (Pb2+).

    PubMed

    Sukumar, Piruthivi; Beech, David J

    2010-02-26

    Lead toxicity is long-recognised but continues to be a major public health problem. Its effects are wide-ranging and include induction of hyper-anxiety states. In general it is thought to act by interfering with Ca(2+) signalling but specific targets are not clearly identified. Transient receptor potential canonical 5 (TRPC5) is a Ca(2+)-permeable ion channel that is linked positively to innate fear responses and unusual amongst ion channels in being stimulated by trivalent lanthanides, which include gadolinium. Here we show investigation of the effect of lead, which is a divalent ion (Pb(2+)). Intracellular Ca(2+) and whole-cell patch-clamp recordings were performed on HEK 293 cells conditionally over-expressing TRPC5 or other TRP channels. Extracellular application of Pb(2+) stimulated TRPC5 at concentrations greater than 1 microM. Control cells without TRPC5 showed little or no response to Pb(2+) and expression of other TRP channels (TRPM2 or TRPM3) revealed partial inhibition by 10 microM Pb(2+). The stimulatory effect on TRPC5 depended on an extracellular residue (E543) near the ion pore: similar to gadolinium action, E543Q TRPC5 was resistant to Pb(2+) but showed normal stimulation by the receptor agonist sphingosine-1-phosphate. The study shows that Pb(2+) is a relatively potent stimulator of the TRPC5 channel, generating the hypothesis that a function of the channel is to sense metal ion poisoning.

  12. Lead concentration in meat from lead-killed moose and predicted human exposure using Monte Carlo simulation.

    PubMed

    Lindboe, M; Henrichsen, E N; Høgåsen, H R; Bernhoft, A

    2012-01-01

    Lead-based hunting ammunitions are still common in most countries. On impact such ammunition releases fragments which are widely distributed within the carcass. In Norway, wild game is an important meat source for segments of the population and 95% of hunters use lead-based bullets. In this paper, we have investigated the lead content of ground meat from moose (Alces alces) intended for human consumption in Norway, and have predicted human exposure through this source. Fifty-two samples from different batches of ground meat from moose killed with lead-based bullets were randomly collected. The lead content was measured by atomic absorption spectroscopy. The lead intake from exposure to moose meat over time, depending on the frequency of intake and portion size, was predicted using Monte Carlo simulation. In 81% of the batches, lead levels were above the limit of quantification of 0.03 mg kg(-1), ranging up to 110 mg kg(-1). The mean lead concentration was 5.6 mg kg(-1), i.e. 56 times the European Commission limit for lead in meat. For consumers eating a moderate meat serving (2 g kg(-1) bw), a single serving would give a lead intake of 11 µg kg(-1) bw on average, with maximum of 220 µg kg(-1) bw. Using Monte Carlo simulation, the median (and 97.5th percentile) predicted weekly intake of lead from moose meat was 12 µg kg(-1) bw (27 µg kg(-1) bw) for one serving per week and 25 µg kg(-1) bw (45 µg kg(-1) bw) for two servings per week. The results indicate that the intake of meat from big game shot with lead-based bullets imposes a significant contribution to the total human lead exposure. The provisional tolerable weekly intake set by the World Health Organization (WHO) of 25 µg kg(-1) bw is likely to be exceeded in people eating moose meat on a regular basis. The European Food Safety Authority (EFSA) has recently concluded that adverse effects may be present at even lower exposure doses. Hence, even occasional consumption of big game meat with lead levels as

  13. Immune stimulation following dermal exposure to unsintered indium tin oxide

    PubMed Central

    Brock, Kristie; Anderson, Stacey E.; Lukomska, Ewa; Long, Carrie; Anderson, Katie; Marshall, Nikki; Meade, B. Jean

    2015-01-01

    In recent years, several types of pulmonary pathology, including alveolar proteinosis, fibrosis, and emphysema, have been reported in workers in the indium industry. To date, there remains no clear understanding of the underlying mechanism(s). Pulmonary toxicity studies in rats and mice have demonstrated the development of mediastinal lymph node hyperplasia and granulomas of mediastinal lymph nodes and bronchus-associated lymphoid tissues following exposure to indium tin oxide. Given the association between exposure to other metals and the development of immune-mediated diseases, these studies were undertaken to begin to investigate the immuno-modulatory potential of unsintered indium tin oxide (uITO) in a mouse model. Using modifications of the local lymph node assay, BALB/c mice (five animals/group) were exposed topically via intact or breached skin or injected intradermally at the base of the ear pinnae with either vehicle or increasing concentrations 2.5–10% uITO (90:10 indium oxide/tin oxide, particle size <50 nm). Dose-responsive increases in lymphocyte proliferation were observed with a calculated EC3 of 4.7% for the intact skin study. Phenotypic analysis of draining lymph node cells following intradermal injection with 5% uITO yielded a profile consistent with a T-cell-mediated response. These studies demonstrate the potential for uITO to induce sensitization and using lymphocyte proliferation as a biomarker of exposure, and demonstrate the potential for uITO to penetrate both intact and breached skin. PMID:24164313

  14. Immune stimulation following dermal exposure to unsintered indium tin oxide.

    PubMed

    Brock, Kristie; Anderson, Stacey E; Lukomska, Ewa; Long, Carrie; Anderson, Katie; Marshall, Nikki; Meade, B Jean

    2014-01-01

    In recent years, several types of pulmonary pathology, including alveolar proteinosis, fibrosis, and emphysema, have been reported in workers in the indium industry. To date, there remains no clear understanding of the underlying mechanism(s). Pulmonary toxicity studies in rats and mice have demonstrated the development of mediastinal lymph node hyperplasia and granulomas of mediastinal lymph nodes and bronchus-associated lymphoid tissues following exposure to indium tin oxide. Given the association between exposure to other metals and the development of immune-mediated diseases, these studies were undertaken to begin to investigate the immuno-modulatory potential of unsintered indium tin oxide (uITO) in a mouse model. Using modifications of the local lymph node assay, BALB/c mice (five animals/group) were exposed topically via intact or breached skin or injected intradermally at the base of the ear pinnae with either vehicle or increasing concentrations 2.5-10% uITO (90:10 indium oxide/tin oxide, particle size <50 nm). Dose-responsive increases in lymphocyte proliferation were observed with a calculated EC3 of 4.7% for the intact skin study. Phenotypic analysis of draining lymph node cells following intradermal injection with 5% uITO yielded a profile consistent with a T-cell-mediated response. These studies demonstrate the potential for uITO to induce sensitization and using lymphocyte proliferation as a biomarker of exposure, and demonstrate the potential for uITO to penetrate both intact and breached skin.

  15. Lead exposure: Public and occupational health hazards. (Latest citations from Pollution abstracts). Published Search

    SciTech Connect

    1995-12-01

    The bibliography contains citations concerning the effects of chronic lead exposure in humans and animals. The citations explore lead exposure resulting from occupational hazards, automobile emissions, and air pollution. Lead absorption in children is discussed. The clinical features of lead toxicity are noted, and biochemical assays for the quantification of blood and tissue lead levels are discussed. D-aminolevulinic acid dehydratase and its relation to blood lead levels are cited.(Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

  16. In vivo genotoxic effects of smoking and occupational lead exposure in printing press workers.

    PubMed

    Rajah, T; Ahuja, Y R

    1995-02-01

    The objective of the present study was to evaluate the genotoxicity of a combination exposure to lead and smoking in workers from the printing industry and also to examine the possible interaction between the two agents. Individuals were classified into 4 different groups: control group, lead-exposed group, smokers and the double-exposure group. Chromosomal analysis was carried out according to conventional methods. Our preliminary study shows that lead-exposed individuals had a significantly increased frequency of sister chromatid exchanges. Further, double exposure to smoking and lead inhibits mitosis.

  17. MC-LR Exposure Leads to Subfertility of Female Mice and Induces Oxidative Stress in Granulosa Cells.

    PubMed

    Wu, Jiang; Yuan, Mingming; Song, Yuefeng; Sun, Feng; Han, Xiaodong

    2015-12-02

    Health risk of human exposure to microcystin-leucine arginine (MC-LR) has aroused more and more attention over the past few decades. In the present study, MC-LR was orally administered to female mice at 0, 1, 10 and 40 μg/L for three and six months. We found that chronic exposure to MC-LR at environmental levels could stimulate follicle atresia and lead to decreased developmental follicles, accompanied by a reduction of gonadosomatic index (GSI). In line with the irregular gonadal hormone level and estrus cycles, subfertility of female mice was also confirmed by analyzing numbers of litters and pups. The in vitro study suggested that granulosa cells could uptake MC-LR and should be the target of the toxicant. Oxidative stress in granulose cells induced by MC-LR promoted follicle atresia and eventually leads to female subfertility.

  18. MC-LR Exposure Leads to Subfertility of Female Mice and Induces Oxidative Stress in Granulosa Cells

    PubMed Central

    Wu, Jiang; Yuan, Mingming; Song, Yuefeng; Sun, Feng; Han, Xiaodong

    2015-01-01

    Health risk of human exposure to microcystin-leucine arginine (MC-LR) has aroused more and more attention over the past few decades. In the present study, MC-LR was orally administered to female mice at 0, 1, 10 and 40 μg/L for three and six months. We found that chronic exposure to MC-LR at environmental levels could stimulate follicle atresia and lead to decreased developmental follicles, accompanied by a reduction of gonadosomatic index (GSI). In line with the irregular gonadal hormone level and estrus cycles, subfertility of female mice was also confirmed by analyzing numbers of litters and pups. The in vitro study suggested that granulosa cells could uptake MC-LR and should be the target of the toxicant. Oxidative stress in granulose cells induced by MC-LR promoted follicle atresia and eventually leads to female subfertility. PMID:26633508

  19. Prenatal tobacco, marijuana, stimulant, and opiate exposure: outcomes and practice implications.

    PubMed

    Minnes, Sonia; Lang, Adelaide; Singer, Lynn

    2011-07-01

    Abuse of drugs by pregnant women both in the United States and worldwide has raised many questions regarding the effects of prenatal drug exposure on the developing fetus and subsequent child outcomes. Studies using the neurobehavioral teratology model have been undertaken to determine specific prenatal drug effects on cognitive and behavioral development. Here we summarize the findings of studies that have investigated the developmental effects of prenatal exposure to tobacco, marijuana, stimulants, and opiates. These studies consider the timing and amount of prenatal exposure; other drug exposures; maternal characteristics; and other health, nutritional, and environmental factors. We review treatment options for pregnant, substance-dependent women and therapeutic interventions for exposed children.

  20. Multi-Omics Reveals that Lead Exposure Disturbs Gut Microbiome Development, Key Metabolites, and Metabolic Pathways.

    PubMed

    Gao, Bei; Chi, Liang; Mahbub, Ridwan; Bian, Xiaoming; Tu, Pengcheng; Ru, Hongyu; Lu, Kun

    2017-03-16

    Lead exposure remains a global public health issue, and the recent Flint water crisis has renewed public concern about lead toxicity. The toxicity of lead has been well established in a variety of systems and organs. The gut microbiome has been shown to be highly involved in many critical physiological processes, including food digestion, immune system development, and metabolic homeostasis. However, despite the key role of the gut microbiome in human health, the functional impact of lead exposure on the gut microbiome has not been studied. The aim of this study is to define gut microbiome toxicity induced by lead exposure in C57BL/6 mice using multiomics approaches, including 16S rRNA sequencing, whole genome metagenomics sequencing, and gas chromatography-mass spectrometry (GC-MS) metabolomics. 16S rRNA sequencing revealed that lead exposure altered the gut microbiome trajectory and phylogenetic diversity. Metagenomics sequencing and metabolomics profiling showed that numerous metabolic pathways, including vitamin E, bile acids, nitrogen metabolism, energy metabolism, oxidative stress, and the defense/detoxification mechanism, were significantly disturbed by lead exposure. These perturbed molecules and pathways may have important implications for lead toxicity in the host. Taken together, these results demonstrated that lead exposure not only altered the gut microbiome community structures/diversity but also greatly affected metabolic functions, leading to gut microbiome toxicity.

  1. Towards the prevention of lead exposure in South Africa: contemporary and emerging challenges.

    PubMed

    Mathee, Angela

    2014-12-01

    The prevention of lead exposure continues to constitute a major public health challenge in developed countries. In well-resourced countries major lead exposure reduction interventions have resulted in significant improvements in childhood blood lead distributions. In developing countries on the other hand, while lead exposure and poisoning remain serious public health concerns, a range of prevailing factors and circumstances, such as poverty, a large informal sector, competing public health challenges, low levels of awareness of lead hazards and weak capacity to enforce legislation, contribute to an increase in the scale and intensity of the challenge, and limit the prospects of comparable success in the foreseeable future. This paper collates available information to illustrate that despite some progress, a wide range of sources of lead exist in South Africa, and that certain settings and groups continue to be at high risk of lead exposure. Lead exposure in relation to paint, mining, lead melting in subsistence fishing communities, the consumption of Ayurvedic medicines and food production is described, and discussed with regard to the key factors hindering efforts to prevent lead poisoning and exposure in South Africa and many other developing countries. Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.

  2. Transcranial direct current stimulation (tDCS) of the parietal cortex leads to increased false recognition.

    PubMed

    Pergolizzi, Denise; Chua, Elizabeth F

    2015-01-01

    A robust finding is that brain activity in the lateral posterior parietal cortex (PPC) correlates with successful recognition. Here we test whether the PPC has a causal role in memory retrieval using transcranial direct current stimulation (tDCS). Participants were given a modified version of the Deese-Roediger-McDermott (DRM) paradigm, a well-established method for producing false recognition with high confidence. In Experiment 1, false recognition was significantly greater for active compared to sham tDCS when the anode was placed over left parietal cortex (CP3) and the cathode over right parietal cortex (CP4). These findings were replicated in Experiment 2, with both anode CP3/cathode CP4 and anode CP4/cathode CP3 active stimulation leading to greater false recognition. Differences also emerged, with anode CP4/cathode CP3 active stimulation leading to greater hits. Our findings support the proposal that the lateral PPC plays a causal role in episodic memory retrieval and can lead to enhanced subjective aspects of memory.

  3. Occupational lead exposure in Los Angeles County: an occupational risk surveillance strategy.

    PubMed

    Papanek, P J; Ward, C E; Gilbert, K M; Frangos, S A

    1992-01-01

    To better understand occupational lead exposures in Los Angeles County, we undertook a questionnaire survey of lead-using industrial facilities not previously identified by county health department staff. Previously our staff had identified 112 lead-using companies with approximately 2,000 lead-exposed workers countywide. For this survey, we developed a database of 1,353 possible lead-using industrial facilities from several sources, including community "right-to-know" databases, air pollution or sewer permit records, or other environmental databases. A questionnaire interview was completed with 1,001 (81%) of these companies, yielding 178 previously unidentified facilities employing 7,734 workers with potentially significant occupational lead exposures. Compliance with the OSHA lead standard was often poor in these facilities, particularly for workplaces with 20 or fewer employees. Devoting more public health resources to targeted identification of such industrial facilities and to educational outreach would likely help control occupational lead exposure.

  4. Glutathione, glutathione-related enzymes, and oxidative stress in individuals with subacute occupational exposure to lead.

    PubMed

    Dobrakowski, Michał; Pawlas, Natalia; Hudziec, Edyta; Kozłowska, Agnieszka; Mikołajczyk, Agnieszka; Birkner, Ewa; Kasperczyk, Sławomir

    2016-07-01

    The aim of the study was to investigate the influence of subacute exposure to lead on the glutathione-related antioxidant defense and oxidative stress parameters in 36 males occupationally exposed to lead for 40±3.2days. Blood lead level in the examined population increased significantly by 359% due to lead exposure. Simultaneously, erythrocyte glutathione level decreased by 16%, whereas the activity of glutathione-6-phosphate dehydrogenase in erythrocytes and leukocytes decreased by 28% and 10%, respectively. Similarly, the activity of glutathione-S-transferase in erythrocytes decreased by 45%. However, the activity of glutathione reductase in erythrocytes and leukocytes increased by 26% and 6%, respectively, whereas the total oxidant status value in leukocytes increased by 37%. Subacute exposure to lead results in glutathione pool depletion and accumulation of lipid peroxidation products; however, it does not cause DNA damage. Besides, subacute exposure to lead modifies the activity of glutathione-related enzymes.

  5. Lead Exposure and Oxidative Stress: A Systematic Review.

    PubMed

    Lopes, Ana Carolina B Almeida; Peixe, Tiago S; Mesas, Arthur E; Paoliello, Monica M B

    2016-01-01

    Lead is an environmental toxicant that can induce oxidative stress (OS) via reactive oxygen species (ROS) generation, which has been reported as an important mechanism underlying lead toxicity (Gurer and Ercal 2000; Pande and Flora 2002; Kasperczyk et al. 2004a; Farmand et al. 2005; Verstraeten et al. 2008; Wang et al. 2009; Martinez-Haro et al. 2011). OS occurs when the generation of ROS exceeds the antioxidant system's ability to defend cells against oxidized molecules. ROS is a term generally used to refer to free radicals derived from O2 (e.g., superoxide anions [O2-] and hydroxyl radicals [OH-]) or to non-radical species (e.g. hydrogen peroxide [H2O2]) (Halliwell and Cross 1994).

  6. [Risk assessment of lead exposure from different intake pathways for children in Wuhan City].

    PubMed

    Hao, Han-Zhou; Chen, Tong-Bin; Wu, Ji-Liang; Lei, Mei; Tian, Hui; Zu, Wen-Pu; Zhong, Xue-Bin

    2012-06-01

    70 sampling points were set in Wuhan City to collect soil, dust, air and food samples. According to the U. S. EPA recommended childhood lead exposure parameters, U. S. EPA human exposure risk assessment method was used to assess the potential health risk of different pathway exposures of children in Wuhan City to lead. The results of calculation show: Wuhan urban children's daily lead exposure is 1.20 x 10(-3) mg x (kg x d)(-1). The digestive tract is the main way for children's exposure to lead, with the exposure of 1.04 x 10(-3) mg x (kg x d)(-1), followed by the respiratory route and dermal absorption route, the exposures were 0.153 x 10(-3) mg x (kg x d)(-1) and 8.56 x 10(-7) mg x (kg x d)(-1) respectively. Pathways of the digestive tract, ingestion of soil or dust lead exposure accounted for 52.0% of the total exposure, through the digestive tract of soil or dust ingestion is the main route of exposure. Monte-Carlo method was used to simulate the pathway in the digestive tract, the amount of lead exposure through ingestion of soil was 2. 48 x 10(-2) mg x d(-1). The probability that exceeded the PTDI (Provisional Tolerable Daily Intake) specified by JECFA (The Joint FAO/WHO Expert Committee on Food Additives) was 2.1%. The results of the risk assessment indicate that lead exposure risks from the digestive tract, respiratory tract, skin absorption are less than the maximum acceptable risk level 5.0 x 10(-5) respectively and the risk associated with skin absorption of lead is less than the negligible risk level 1 x 10(-8). Application of Kriging interpolation method, Wuhan City children lead exposure value on spatial distribution were obtained, and Qingshan district and Jiangan district have a high level of children lead exposure. The aggregate risk index of Wuhan City children lead exposure was yield by using the indicator Kriging.

  7. Mission-Area Guide to Lead-Exposure Control

    DTIC Science & Technology

    1996-03-01

    Project, American Journal of Public Health, Vol. 83, No. 3, March 1993. Block, Seamer S., Disinfection , Sterilization , and Preservation, 4th Edition...Thomas Lillich, Disinfection and Sterilization in Dental Practice, McGraw-Hill, 1978. Center for Disease Control, Adult Blood Lead Epidemiology and...Data Sheets for Sterilizers . MDT Biological Company. 1985. McLaughlin, William J. President, ToxCo, Claremont, California, telephone conversation

  8. Can a father's exposure lead to illness in his children

    SciTech Connect

    Stone, R.

    1992-10-02

    There is an urgent need for studies to elucidate mechanisms underlying evidence mechanisms underlying evidence that many different types of paternal exposure induce changes in sperm or semen that could affect children's health. Epidemiology, of course, is only half of the equation that describes male-mediated toxicity. The other half is the biological examination of mechanisms whereby damage to sperm might affect the next generation. In this area, geneticists and toxicologists have had a firm starting point: It's been known for decades that certain toxins and radiation can damage sperm. Research suggests that different chemicals exert their maximum damage on sperm at three stages of sperm production, with most chemicals tested affecting the stage during which early spermatozoa and late spermatids are formed. The problem, however, is that none of these defects has been linked specifically to certain types of birth defects or diseases.

  9. Remilling of salvaged wood siding coated with lead-based paint. Part 1, Lead exposure

    Treesearch

    Robert H. Falk; John J. Janowiak; Stephen D. Cosper; Susan A. Drozdz

    2005-01-01

    It is well known that the lead contained in lead-based paint (LBP) can pose a serious human health risk if ingested. In our nation’s building infrastructure, millions of meters of high quality salvageable lumber have been coated with LBP. The study presented in this and a companion paper investigated the feasibility of producing several standardized wood product...

  10. Airborne exposure and soil levels associated with lead abatement of a steel tank.

    PubMed

    Lange, John H

    2002-02-01

    This study reports on airborne exposure levels and soil concentrations of lead in regard to abatement of a steel structure (water tank). The tank was de-leaded by abrasive sand blasting. The ball of the tank had a lead surface level that exceeded the Environmental Protection Agency (EPA) definition of lead-based paint (LBP) (0.5% lead), but paint on stem and base was below this criterion. Personal and area airborne samples were collected during different activities of lead abatement of the tank. Summary results suggest during abrasive blasting of ball and stem/base personal exposure levels, as reported with arithmetic and geometric means, exceed the Occupational Safety and Health Administration (OSHA) permissible exposure limit (50 microg/m3). Highest personal exposure (occupational exposure) was associated with blasting of ball. Distribution of airborne and soil samples suggest non-normality and is best represented by a logarithmic form. Geometric standard deviations for air and soil lead support a non-normal distribution. Outlying values were found for personal and area air samples. Exposure levels associated with blasting stem/base section of tank support OSHA's policy requiring air monitoring of work at levels below the criterion established by EPA in identifying LBP. Area samples were statistically lower than personal samples associated with blasting ball and stem/base of tank. Exposure data suggest that workers performing abatement on steel structures have elevated lead exposure from surface lead. Respirator protection requirements are discussed. Soil lead concentration was suggested to decrease as distance increased from tank. Soil lead is suggested to be a result of deposition from LBP on tank surface. Minimal efforts were required to reduce average lead soil levels below EPA's upper acceptable criterion (1200 ppm Pb).

  11. In situ repair of vagus nerve stimulator lead damage: technical note.

    PubMed

    Ralston, Ashley; Ogden, Patti; Kohrman, Michael H; Frim, David M

    2016-12-01

    Vagus nerve stimulators (VNSs) are currently an accepted treatment for intractable epilepsy not amenable to ablative surgery. Battery death and lead damage are the main reasons for reoperation in patients with VNSs. In general, any damage to the lead requires revision surgery to remove the helical electrodes from the vagus nerve and replace the electrode array and wire. The electrodes are typically scarred and difficult to remove from the vagus nerve without injury. The authors describe 6 patients with VNSs who presented with low lead impedance on diagnostic testing, leading to the intraoperative finding of lead insulation disruption, or who were found incidentally at the time of implantable pulse generator battery replacement to have a tear in the outer insulation of the electrode wire. Instead of replacement, the wire insulation was repaired and reinforced in situ, leading to normal impedance testing. All 6 devices remained functional over a follow-up period of up to 87 months, with 2 of the 6 patients having a relatively shorter follow-up of only 12 months. This technique, applicable in a subset of patients with VNSs requiring lead exploration, obviates the need for lead replacement with its attendant risks.

  12. Lead exposure in adult males in urban Transvaal Province, South Africa during the apartheid era.

    PubMed

    Hess, Catherine A; Cooper, Matthew J; Smith, Martin J; Trueman, Clive N; Schutkowski, Holger

    2013-01-01

    Human exposure to lead is a substantial public health hazard worldwide and is particularly problematic in the Republic of South Africa given the country's late cessation of leaded petrol. Lead exposure is associated with a number of serious health issues and diseases including developmental and cognitive deficiency, hypertension and heart disease. Understanding the distribution of lifetime lead burden within a given population is critical for reducing exposure rates. Femoral bone from 101 deceased adult males living in urban Transvaal Province (now Gauteng Province), South Africa between 1960 and 1998 were analyzed for lead concentration by Inductively Coupled Plasma Mass Spectrometry (ICP-MS). Of the 72 black and 29 white individuals sampled, chronic lead exposure was apparent in nearly all individuals. White males showed significantly higher median bone lead concentration (ME = 10.04 µg·g(-1)), than black males (ME = 3.80 µg·g(-1)) despite higher socioeconomic status. Bone lead concentration covaries significantly, though weakly, with individual age. There was no significant temporal trend in bone lead concentration. These results indicate that long-term low to moderate lead exposure is the historical norm among South African males. Unexpectedly, this research indicates that white males in the sample population were more highly exposed to lead.

  13. Low level of lead can induce phosphatidylserine exposure and erythrophagocytosis: a new mechanism underlying lead-associated anemia.

    PubMed

    Jang, Won-Hee; Lim, Kyung-Min; Kim, Keunyoung; Noh, Ji-Yoon; Kang, Seojin; Chang, Youn-Kyeong; Chung, Jin-Ho

    2011-07-01

    Anemia is probably one of the most well-known toxic effects of lead. Previously, lead-induced anemia was considered to be from the inhibition of δ-aminolevulinic acid dehydratase participating in the heme biosynthesis. However, little is known whether lead could affect the destruction of erythrocyte, another important factor for anemia. In the present study, we demonstrated that lead could accelerate the splenic sequestration of erythrocytes through phosphatidylserine (PS) exposure and subsequently increased erythrophagocytosis. In freshly isolated human erythrocytes, Pb(2+)- induced PS exposure at relatively low concentrations (∼0.1 μM) by inhibiting flippase, a key aminophospholipid translocase for the maintenance of PS asymmetry and adenosine triphosphate depletion appeared to underlie this phenomenon. Abnormal shape changes of erythrocytes and microvesicle generation and other triggers for the erythrophagocytosis were also observed in the Pb(2+)-exposed erythrocytes. In vitro data showed that human macrophage indeed recognized and phagocytosis PS-exposed erythrocytes. In good accordance with these in vitro results, the oral administration of Pb(2+) increased PS exposure on erythrocytes in rat in vivo. In addition, reduction of hematocrit and hemoglobin and increased spleen weight were observed along with enhanced splenic sequestration of erythrocytes in the rats exposed to Pb(2+) subchronically for 4 weeks through drinking water. In conclusion, these results suggest that Pb(2+)-induced anemia may be explained at least in part by increased PS exposure on erythrocytes, erythrophagocytosis, and splenic sequestration.

  14. Urban gardens: lead exposure, recontamination mechanisms, and implications for remediation design.

    PubMed

    Clark, Heather F; Hausladen, Debra M; Brabander, Daniel J

    2008-07-01

    Environmental lead contamination is prevalent in urban areas where soil represents a significant sink and pathway of exposure. This study characterizes the speciation of lead that is relevant to local recontamination and to human exposure in the backyard gardens of Roxbury and Dorchester, MA, USA. One hundred forty-one backyard gardens were tested by X-ray fluorescence, and 81% of gardens have lead levels above the US EPA action limit of 400 microg/g. Raised gardening beds are the in situ exposure reduction method used in the communities to promote urban gardening. Raised beds were tested for lead and the results showed that the lead concentration increased from an initial range of 150+/-40 microg/g to an average of 336 microg/g over 4 years. The percent distribution of lead in the fine grain soil (<100 microm) and the trace metal signature of the raised beds support the conclusion that the mechanism of recontamination is wind-transported particles. Scanning electron microscopy and sequential extraction were used to characterize the speciation of lead, and the trace metal signature of the fine grain soil in both gardens and raised gardening beds is characteristic of lead-based paint. This study demonstrates that raised beds are a limited exposure reduction method and require maintenance to achieve exposure reduction goals. An exposure model was developed based on a suite of parameters that combine relevant values from the literature with site-specific quantification of exposure pathways. This model suggests that consumption of homegrown produce accounts for only 3% of children's daily exposure of lead while ingestion of fine grained soil (<100 microm) accounts for 82% of the daily exposure. This study indicates that urban lead remediation on a yard-by-yard scale requires constant maintenance and that remediation may need to occur on a neighborhood-wide scale.

  15. Urban gardens: Lead exposure, recontamination mechanisms, and implications for remediation design

    SciTech Connect

    Clark, Heather F. Hausladen, Debra M.; Brabander, Daniel J.

    2008-07-15

    Environmental lead contamination is prevalent in urban areas where soil represents a significant sink and pathway of exposure. This study characterizes the speciation of lead that is relevant to local recontamination and to human exposure in the backyard gardens of Roxbury and Dorchester, MA, USA. One hundred forty-one backyard gardens were tested by X-ray fluorescence, and 81% of gardens have lead levels above the US EPA action limit of 400 {mu}g/g. Raised gardening beds are the in situ exposure reduction method used in the communities to promote urban gardening. Raised beds were tested for lead and the results showed that the lead concentration increased from an initial range of 150{+-}40 {mu}g/g to an average of 336 {mu}g/g over 4 years. The percent distribution of lead in the fine grain soil (<100 {mu}m) and the trace metal signature of the raised beds support the conclusion that the mechanism of recontamination is wind-transported particles. Scanning electron microscopy and sequential extraction were used to characterize the speciation of lead, and the trace metal signature of the fine grain soil in both gardens and raised gardening beds is characteristic of lead-based paint. This study demonstrates that raised beds are a limited exposure reduction method and require maintenance to achieve exposure reduction goals. An exposure model was developed based on a suite of parameters that combine relevant values from the literature with site-specific quantification of exposure pathways. This model suggests that consumption of homegrown produce accounts for only 3% of children's daily exposure of lead while ingestion of fine grained soil (<100 {mu}m) accounts for 82% of the daily exposure. This study indicates that urban lead remediation on a yard-by-yard scale requires constant maintenance and that remediation may need to occur on a neighborhood-wide scale.

  16. Mapping the spatio-temporal risk of lead exposure in apex species for more effective mitigation.

    PubMed

    Mateo-Tomás, Patricia; Olea, Pedro P; Jiménez-Moreno, María; Camarero, Pablo R; Sánchez-Barbudo, Inés S; Rodríguez Martín-Doimeadios, Rosa C; Mateo, Rafael

    2016-07-27

    Effective mitigation of the risks posed by environmental contaminants for ecosystem integrity and human health requires knowing their sources and spatio-temporal distribution. We analysed the exposure to lead (Pb) in griffon vulture Gyps fulvus-an apex species valuable as biomonitoring sentinel. We determined vultures' lead exposure and its main sources by combining isotope signatures and modelling analyses of 691 bird blood samples collected over 5 years. We made yearlong spatially explicit predictions of the species risk of lead exposure. Our results highlight elevated lead exposure of griffon vultures (i.e. 44.9% of the studied population, approximately 15% of the European, showed lead blood levels more than 200 ng ml(-1)) partly owing to environmental lead (e.g. geological sources). These exposures to environmental lead of geological sources increased in those vultures exposed to point sources (e.g. lead-based ammunition). These spatial models and pollutant risk maps are powerful tools that identify areas of wildlife exposure to potentially harmful sources of lead that could affect ecosystem and human health. © 2016 The Author(s).

  17. Mapping the spatio-temporal risk of lead exposure in apex species for more effective mitigation

    PubMed Central

    Mateo-Tomás, Patricia; Olea, Pedro P.; Jiménez-Moreno, María; Camarero, Pablo R.; Sánchez-Barbudo, Inés S.; Rodríguez Martín-Doimeadios, Rosa C.; Mateo, Rafael

    2016-01-01

    Effective mitigation of the risks posed by environmental contaminants for ecosystem integrity and human health requires knowing their sources and spatio-temporal distribution. We analysed the exposure to lead (Pb) in griffon vulture Gyps fulvus—an apex species valuable as biomonitoring sentinel. We determined vultures' lead exposure and its main sources by combining isotope signatures and modelling analyses of 691 bird blood samples collected over 5 years. We made yearlong spatially explicit predictions of the species risk of lead exposure. Our results highlight elevated lead exposure of griffon vultures (i.e. 44.9% of the studied population, approximately 15% of the European, showed lead blood levels more than 200 ng ml−1) partly owing to environmental lead (e.g. geological sources). These exposures to environmental lead of geological sources increased in those vultures exposed to point sources (e.g. lead-based ammunition). These spatial models and pollutant risk maps are powerful tools that identify areas of wildlife exposure to potentially harmful sources of lead that could affect ecosystem and human health. PMID:27466455

  18. Screening for lead exposure using a geographic information system

    SciTech Connect

    Wartenberg, D. )

    1992-12-01

    Screening programs for lead overexposure typically target high-risk populations by identifying regions with common risk markers (older housing, poverty, etc.). While more useful than untargeted screening programs, targeted programs are limited by the geographic resolution of the risk-factor information. A geographic information system can make screening programs more effective and more cost-efficient by mapping cases of overexposure, identifying high-incidence neighborhoods warranting screening, and validating risk-factor-based prediction rules. 5 refs., 5 figs., 2 tabs.

  19. Report on radiation exposure of lead-scintillator stack

    SciTech Connect

    Underwood, D.G.

    1990-11-08

    A stack of lead and scintillator was placed in a neutral beam obtained from targeting 800 GeV protons. Small pieces of film containing radiochromic dye were placed adjacent to the layers of scintillator for the purpose of measuring the radiation dose to the scintillator. Our motivation was to calibrate the radiation dose obtainable in this manner for future tests of scintillator for SSC experiments and to relate dose to flux to check absolute normalization for calculations. We also observed several other radiation effects which should be considered for both damage and compensation in a calorimeter.

  20. Occupational lead exposure among automotive garage workers – a case study for Jimma town, Ethiopia

    PubMed Central

    2012-01-01

    Background In Ethiopia, although there are numerous small-scale and medium industries which use lead-based raw materials that may pose health risks to workers, there are no workplace regulations for lead exposure. Moreover, there are no studies carried out on the blood lead levels (BLLs) of workers or on the contribution of common workplace practices to lead poisoning. Method A cross-sectional study on the BLLs of 45 automotive garage workers and 40 non-garage workers was carried out in the town of Jimma, Ethiopia. In addition to BLL analysis, data on some risk factors such as smoking, and chewing ‘khat’ (the leaves of Catha adulis) were gathered through structured questionnaires and interviews and data analysis was performed using SPSS (version 16). The t-test was used to compare mean BLLs of study groups. The analysis of variance (ANOVA), Kruskal-Wallis, Pearson chi-square and odds ratio tests were used to investigate the associations between specific job type, smoking and/or ‘khat’ chewing, service years and occurrence of non-specific symptoms with BLLs. Results The mean BLL of the automotive-garage workers was found to be significantly greater than that of the controls. The BLLs of all the lead-exposed individuals were found to be over 10 μg/dL, and 53% of them had BLLs ranging 12 – 20 μg/dL, with the remaining 47% having over 20 μg/dL. The BLL of the workers increased with the duration of working in an automotive garage. Individuals involved in manual car painting comprise a larger percentage (58%) of those with the highest BLLs (≥ 20 μg/dL). Lead accumulation in individuals who chew ‘khat’ in the work place was found to be faster than in those who are not used to chewing ‘khat’. ‘Khat’ is an evergreen shrub native to tropical East Africa, with dark green opposite leaves which are chewed when fresh for their stimulating effects. Conclusion The findings of the study have clearly demonstrated that the BLLs of automotive

  1. Lead-Related Genetic Loci, Cumulative Lead Exposure and Incident Coronary Heart Disease: The Normative Aging Study

    PubMed Central

    Weisskopf, Marc G.; Sparrow, David; Schwartz, Joel; Hu, Howard; Park, Sung Kyun

    2016-01-01

    Background Cumulative exposure to lead is associated with cardiovascular outcomes. Polymorphisms in the δ-aminolevulinic acid dehydratase (ALAD), hemochromatosis (HFE), heme oxygenase-1 (HMOX1), vitamin D receptor (VDR), glutathione S-transferase (GST) supergene family (GSTP1, GSTT1, GSTM1), apolipoprotein E (APOE),angiotensin II receptor-1 (AGTR1) and angiotensinogen (AGT) genes, are believed to alter toxicokinetics and/or toxicodynamics of lead. Objectives We assessed possible effect modification by genetic polymorphisms in ALAD, HFE, HMOX1, VDR, GSTP1, GSTT1, GSTM1, APOE, AGTR1 and AGT individually and as the genetic risk score (GRS) on the association between cumulative lead exposure and incident coronary heart disease (CHD) events. Methods We used K-shell-X-ray fluorescence to measure bone lead levels. GRS was calculated on the basis of 22 lead-related loci. We constructed Cox proportional hazard models to compute adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for incident CHD. We applied inverse probability weighting to account for potential selection bias due to recruitment into the bone lead sub-study. Results Significant effect modification was found by VDR, HMOX1, GSTP1, APOE, and AGT genetic polymorphisms when evaluated individually. Further, the bone lead-CHD associations became larger as GRS increases. After adjusting for potential confounders, a HR of CHD was 2.27 (95%CI: 1.50–3.42) with 2-fold increase in patella lead levels, among participants in the top tertile of GRS. We also detected an increasing trend in HRs across tertiles of GRS (p-trend = 0.0063). Conclusions Our findings suggest that lead-related loci as a whole may play an important role in susceptibility to lead-related CHD risk. These findings need to be validated in a separate cohort containing bone lead, lead-related genetic loci and incident CHD data. PMID:27584680

  2. Lead exposure among automobile radiator repair workers and their children in New York City.

    PubMed

    Nunez, C M; Klitzman, S; Goodman, A

    1993-05-01

    Despite a comprehensive Occupational Safety and Health Administration lead standard, exposure to lead continues in many industries. This paper describes a blood lead screening and education program for automobile radiator repair workers and their families in New York City. Results showed that 67% of automobile radiator repair workers (n = 62) in 89% of the shops tested (n = 24) had blood lead levels in excess of 25 micrograms/dl. The vast majority of workers had never been tested previously, and none had received health and safety training regarding occupational lead exposure. Although none of the workers' children's blood lead levels were in excess of then-current guidelines, several had levels which may be associated with subclinical toxicity and in excess of the revised Centers for Disease Control guidelines of 10 micrograms/dl. This project demonstrates that lead exposure in the automotive radiator repair industry continues to be widespread and that local health departments can assist in hazard identification and remediation.

  3. A review of environmental lead exposure and management in Mount Isa, Queensland.

    PubMed

    Forbes, Malcolm; Taylor, Mark Patrick

    2015-01-01

    The public health leadership and management of lead exposure in a lead mining and smelting community in Mount Isa is an ongoing issue. There exists deficiencies in public health and environmental legal frameworks that regulate lead exposure and management in Mount Isa, Queensland. Although some positive practical measures on lead containment have been implemented, evidence suggests they are currently inadequate. Greater investments in public health leadership at a local and state level are required to address the ongoing issue of lead in Mount Isa.

  4. Secondhand Tobacco Smoke: A Source of Lead Exposure in US Children and Adolescents

    PubMed Central

    Apostolou, Andria; Garcia-Esquinas, Esther; Fadrowski, Jeffrey J.; McLain, RN, Pat; Weaver, Virginia M.

    2012-01-01

    Objectives. We evaluated the relationship between secondhand tobacco smoke (SHS) exposure and blood lead levels in US children and adolescents. Methods. We analyzed data from 6830 participants aged 3–19 years in the National Health and Nutrition Examination Survey (1999–2004) who were not active smokers and for whom SHS exposure information and blood lead measurements were available. Results. After multivariable adjustment, participants in the highest quartile of serum cotinine (≥ 0.44 μg/L) had 28% (95% confidence interval = 21%, 36%) higher blood lead levels than had those in the lowest quartile (< 0.03 μg/L). Similarly, blood lead levels were 14% and 24% higher in children who lived with 1 or with 2 or more smokers, respectively, than they were in children living with no smokers. Among participants for whom lead dust information was available, the associations between SHS and blood lead levels were similar before and after adjustment for lead dust concentrations. Conclusions. SHS may contribute to increased blood lead levels in US children. Lead dust does not appear to mediate this association, suggesting inhalation as a major pathway of exposure. Eliminating SHS exposure could reduce lead exposure in children. PMID:21852639

  5. Association between GSTP1 CpG methylation and the early phase of lead exposure.

    PubMed

    Li, Chunping; Yang, Xiaolin; Xu, Ming; Zhang, Jinlong; Sun, Na

    2014-02-01

    GSTP1 is induced by lead, and thus serves as a biomarker of lead exposure. Lead exposure changes DNA methylation status. We attempted to prove that the methylation of the GSTP1 promoter plays an important role in lead toxicity. We conducted a case-control study of 53 workers from a battery plant and 53 age and sex matched healthy volunteers to determine whether the methylation level of the GSTP1 promoter is associated with the risk of lead poisoning. We employed methylation-specific PCR (MSP) in cell models to determine the relationship between the GSTP1 methylation level and lead exposure. We found no association between GSTP1 methylation and lead exposure. The difference in methylation frequencies between the exposure group and the controls was not statistically significant (p = 0.401), and individuals with the methylated GSTP1 gene was not associated with the risk of lead poisoning (adjusted OR = 1.36, 95% CI, 0.22-8.24). This study suggests that GSTP1 methylation is not involved in the early phase of lead toxicity. Further studies should be performed to detect the association between GSTP1 methylation and the risk of lead poisoning in later phases.

  6. Secondhand tobacco smoke: a source of lead exposure in US children and adolescents.

    PubMed

    Apostolou, Andria; Garcia-Esquinas, Esther; Fadrowski, Jeffrey J; McLain, Pat; Weaver, Virginia M; Navas-Acien, Ana

    2012-04-01

    We evaluated the relationship between secondhand tobacco smoke (SHS) exposure and blood lead levels in US children and adolescents. We analyzed data from 6830 participants aged 3-19 years in the National Health and Nutrition Examination Survey (1999-2004) who were not active smokers and for whom SHS exposure information and blood lead measurements were available. After multivariable adjustment, participants in the highest quartile of serum cotinine (≥ 0.44 μg/L) had 28% (95% confidence interval = 21%, 36%) higher blood lead levels than had those in the lowest quartile (< 0.03 μg/L). Similarly, blood lead levels were 14% and 24% higher in children who lived with 1 or with 2 or more smokers, respectively, than they were in children living with no smokers. Among participants for whom lead dust information was available, the associations between SHS and blood lead levels were similar before and after adjustment for lead dust concentrations. SHS may contribute to increased blood lead levels in US children. Lead dust does not appear to mediate this association, suggesting inhalation as a major pathway of exposure. Eliminating SHS exposure could reduce lead exposure in children.

  7. Impact of developmental lead exposure on splenic factors

    SciTech Connect

    Kasten-Jolly, Jane; Heo, Yong; Lawrence, David A.

    2010-09-01

    Lead (Pb) is known to alter the functions of numerous organ systems, including the hematopoietic and immune systems. Pb can induce anemia and can lower host resistance to bacterial and viral infections. The anemia is due to Pb's inhibition of hemoglobin synthesis and Pb's induction of membrane changes, leading to early erythrocyte senescence. Pb also increases B-cell activation/proliferation and skews T-cell help (Th) toward Th2 subset generation. The specific mechanisms for many of the Pb effects are, as yet, not completely understood. Therefore, we performed gene expression analysis, via microarray, on RNA from the spleens of developmentally Pb-exposed mice, in order to gain further insight into these Pb effects. Splenic RNA microarray analysis indicated strong up-regulation of genes coding for proteolytic enzymes, lipases, amylase, and RNaseA. The data also showed that Pb affected the expression of many genes associated with innate immunity. Analysis of the microarray results via GeneSifter software indicated that Pb increased apoptosis, B-cell differentiation, and Th2 development. Direct up-regulation by Pb of expression of the gene encoding the heme-regulated inhibitor (HRI) suggested that Pb can decrease erythropoiesis by blocking globin mRNA translation. Pb's high elevation of digestive/catabolizing enzymes could generate immunogenic self peptides. With Pb's potential to induce new self-peptides and to enhance the expression of caspases, cytokines, and other immunomodulators, further evaluation of Pb's involvement in autoimmune phenomena, especially Th2-mediated autoantibody production, and alteration of organ system activities is warranted.

  8. Fetal lead exposure at each stage of pregnancy as a predictor of infant mental development.

    PubMed

    Hu, Howard; Téllez-Rojo, Martha María; Bellinger, David; Smith, Donald; Ettinger, Adrienne S; Lamadrid-Figueroa, Héctor; Schwartz, Joel; Schnaas, Lourdes; Mercado-García, Adriana; Hernández-Avila, Mauricio

    2006-11-01

    The impact of prenatal lead exposure on neurodevelopment remains unclear in terms of consistency, the trimester of greatest vulnerability, and the best method for estimating fetal lead exposure. We studied prenatal lead exposure's impact on neurodevelopment using repeated measures of fetal dose as reflected by maternal whole blood and plasma lead levels. We measured lead in maternal plasma and whole blood during each trimester in 146 pregnant women in Mexico City. We then measured umbilical cord blood lead at delivery and, when offspring were 12 and 24 months of age, measured blood lead and administered the Bayley Scales of Infant Development. We used multivariate regression, adjusting for covariates and 24-month blood lead, to compare the impacts of our pregnancy measures of fetal lead dose. Maternal lead levels were moderately high with a first-trimester blood lead mean (+/- SD) value of 7.1 +/- 5.1 microg/dL and 14% of values >or=10 microg/dL. Both maternal plasma and whole blood lead during the first trimester (but not in the second or third trimester) were significant predictors (p < 0.05) of poorer Mental Development Index (MDI) scores. In models combining all three trimester measures and using standardized coefficients, the effect of first-trimester maternal plasma lead was somewhat greater than the effect of first-trimester maternal whole blood lead and substantially greater than the effects of second- or third-trimester plasma lead, and values averaged over all three trimesters. A 1-SD change in first-trimester plasma lead was associated with a reduction in MDI score of 3.5 points. Postnatal blood lead levels in the offspring were less strongly correlated with MDI scores. Fetal lead exposure has an adverse effect on neurodevelopment, with an effect that may be most pronounced during the first trimester and best captured by measuring lead in either maternal plasma or whole blood.

  9. Effect of sublethal lead exposure on gastric motility of red-tailed hawks.

    PubMed

    Lawler, E M; Duke, G E; Redig, P T

    1991-07-01

    In order to determine the effects of low level lead exposure on gastric motility in raptors, strain gage transducers were surgically implanted on the serosal surface of the muscular stomach of three red-tailed hawks. The frequency and amplitude of gastric contractions during ingestion and early digestion were monitored for 1 week under control conditions and for 3 weeks while the birds were fed 0.82 or 1.64 mg lead (as lead acetate) per kg body weight each day. Exposure to these doses did not appreciably affect either the frequency or amplitude of gastric contractions in these birds. This low level lead exposure also had no consistent effect on the regular egestion of pellets of undigested material by hawks. Daily exposure to doses up to 6.55 mg lead/kg body weight did not affect the frequency or timing of pellet egestion, and exposure to 1.64 mg lead/kg did not affect the gastric contractions associated with pellet egestion. Although gastrointestinal dysfunction is often associated with clinical cases of acute lead toxicity, chronic exposure to these low levels of lead acetate did not significantly alter gastric motility in red-tailed hawks.

  10. Differential Effect of Postnatal Lead Exposure on Gene Expression in the Hippocampus and Frontal Cortex

    PubMed Central

    Schneider, J.S.; Mettil, W.; Anderson, D.W.

    2011-01-01

    Although developmental lead exposure is known to have detrimental effects on a variety of cognitive functions that depend on the integrity of the hippocampus and frontal cortex, little is known about how low levels of lead exposure affect expression of key families of genes in these structures. The present study examined the effects of exposure to environmentally-relevant levels of lead during the sensitive early post-weaning period in the rat on the expression profiles of a select number of neurobiologically relevant genes (i.e., genes for neurotrophic factors, NMDA receptors, metabotropic glutamate receptors, synaptic function/plasticity, cell signaling, and transcription/regulation) in the rat hippocampus and frontal cortex. Exposure to lead (180 and 375 ppm lead acetate in food for 30 days) significantly increased blood lead levels (5.8 to 10.3 μg/dl) and significantly affected expression of many of the genes examined. In many instances, lead exposure had different effects on the same gene depending on the brain region in which the expression of that gene was examined. Gene expression in the frontal cortex was often more sensitive to modification than gene expression in the hippocampus. These results suggest that even past infancy, exposures to low levels of lead can have significant effects on gene expression in frontal cortex and the hippocampus with the potential to exert long-term effects on behavior and cognition. PMID:22160880

  11. A task-based approach to assessing lead exposure among iron workers engaged in bridge rehabilitation.

    PubMed

    Goldberg, M; Levin, S M; Doucette, J T; Griffin, G

    1997-03-01

    The assessment of worker exposures to airborne contaminants in the dynamic environment present at most construction sites poses considerable challenges to the industrial hygienist. In this study, we applied a task-based approach to the assessment of lead exposure among structural steel iron workers engaged in a large, complex bridge rehabilitation project. We evaluated the usefulness of task-based exposure data for the development of worker protection programs. Task-specific and multitask samples were collected, and operation-specific and 8-hr time-weighted averages were calculated. The task-specific data showed significant differences in exposure levels among different tasks. Arithmetic mean exposures varied from 1,357 micrograms/m3 lead for torch cutting and 989 micrograms/m3 for scaling to 31 micrograms/m3 for reaming and 4 micrograms/m3 for drilling. Our task-specific data were compared with the task-based exposure levels presented by OSHA in its Lead Exposure in Construction-Interim Final Rule (29 CFR 1926). There was good general agreement between our results and OSHA's reported data. Task-based data were very useful in exposure assessment and much more precise than full-shift and operation-based measurements in guiding strategies for worker protection. These findings suggest that task-based data should routinely be collected in evaluating exposure to lead and perhaps other toxic substances in construction work.

  12. Improved spatial targeting with directionally segmented deep brain stimulation leads for treating essential tremor

    NASA Astrophysics Data System (ADS)

    Keane, Maureen; Deyo, Steve; Abosch, Aviva; Bajwa, Jawad A.; Johnson, Matthew D.

    2012-08-01

    Deep brain stimulation (DBS) in the ventral intermediate nucleus of thalamus (Vim) is known to exert a therapeutic effect on postural and kinetic tremor in patients with essential tremor (ET). For DBS leads implanted near the caudal border of Vim, however, there is an increased likelihood that one will also induce paresthesia side-effects by stimulating neurons within the sensory pathway of the ventral caudal (Vc) nucleus of thalamus. The aim of this computational study was to (1) investigate the neuronal pathways modulated by therapeutic, sub-therapeutic and paresthesia-inducing DBS settings in three patients with ET and (2) determine how much better an outcome could have been achieved had these patients been implanted with a DBS lead containing directionally segmented electrodes (dDBS). Multi-compartment neuron models of the thalamocortical, cerebellothalamic and medial lemniscal pathways were first simulated in the context of patient-specific anatomies, lead placements and programming parameters from three ET patients who had been implanted with Medtronic 3389 DBS leads. The models showed that in these patients, complete suppression of tremor was associated most closely with activating an average of 62% of the cerebellothalamic afferent input into Vim (n = 10), while persistent paresthesias were associated with activating 35% of the medial lemniscal tract input into Vc thalamus (n = 12). The dDBS lead design demonstrated superior targeting of the cerebello-thalamo-cortical pathway, especially in cases of misaligned DBS leads. Given the close proximity of Vim to Vc thalamus, the models suggest that dDBS will enable clinicians to more effectively sculpt current through and around thalamus in order to achieve a more consistent therapeutic effect without inducing side-effects.

  13. Prenatal cigarette exposure and infant learning stimulation as predictors of cognitive control in childhood

    PubMed Central

    Mezzacappa, Enrico; Buckner, John C.; Earls, Felton

    2010-01-01

    Prenatal exposures to neurotoxins and postnatal parenting practices have been shown to independently predict variations in the cognitive development and emotional-behavioral well being of infants and children. We examined the independent contributions of prenatal cigarette exposure and infant learning stimulation, as well as their inter-relationships in predicting variations in the proficiency of executive attention, a core element of cognitive control and self-regulation. Participants were an ethnic-racially, socio-economically diverse sample of 249 children followed from birth in the Project on Human Development in Chicago Neighborhoods. We obtained histories of prenatal exposure to alcohol, cigarettes, and other drugs, and we assessed socio-economic status and learning stimulation during a home visit when the participants were infants. In childhood we utilized the Attention Networks Test to assess the proficiency of executive attention during two home visits, one year apart. Accounting for age, SES, prenatal alcohol exposure, and baseline performance, we found that prenatal cigarette exposure impaired the speed of executive attention. Infant learning stimulation mitigated these effects, and predicted better accuracy of executive attention as well, suggestive of both protective and health promoting effects. Effect sizes for these relations, whether examined independently or by their inter-relationships, were comparable if not greater in magnitude to the effects of age on speed and accuracy, highlighting the importance of these very early experiences in shaping the proficiency of self-regulation. Since executive attention is central to cognitive control and self-regulation, previously described relations between prenatal cigarette exposure, parenting practices, and some forms of childhood psychopathology, may be contingent on how early learning stimulation contributes to the proficiency of executive attention through direct and indirect effects. Furthermore

  14. Prenatal lead exposure modifies the impact of maternal self-esteem on children's inattention behavior

    PubMed Central

    Xu, Jian; Hu, Howard; Wright, Rosalind; Sánchez, Brisa N.; Schnaas, Lourdes; Bellinger, David C.; Park, Sung Kyun; Martínez, Sandra; Hernández-Avila, Mauricio; Téllez-Rojo, Martha Maria; Wright, Robert O.

    2015-01-01

    Objective To prospectively evaluate the association of maternal self-esteem measured when their offspring were toddlers with the subsequent development of attention-deficit-hyperactivity-disorder (ADHD)-like behavior in their school-age offspring and the potential modifying effects of prenatal lead exposure. Study design We evaluated a subsample of 192 mother-child pairs from a long-running birth-cohort project that enrolled mothers in Mexico from 1994 to 2011. Prenatal lead exposure was assessed using cord blood lead and maternal bone lead around delivery (tibia and patella lead, measured by K-x-ray-fluorescence). When children were 2 years old, maternal self-esteem was measured using the Coopersmith-Self-esteem-Inventory. When children were 7-to-15 years old, children's blood lead levels and ADHD symptoms were assessed, and Conners’ Parental-Rating-Scales-Revised (CPRS-R) and Behavior-Rating-Inventory-of-Executive-Function-Parent Form (BRIEF-P) were used as measures of ADHD-like behavior. Results Adjusting for family economic status, marital status, maternal education and age, child's age and sex, and children's current blood lead levels, increased maternal self-esteem was associated with reduced child inattention behavior. Compared with those among high prenatal lead exposure (P25-P100), this association was stronger among low prenatal lead exposure groups (P1-P25, p-values for the interaction effects between prenatal lead exposure and maternal self-esteem levels < 0.10). Each 1-point increase in maternal self-esteem scores was associated with 0.6-to-1.3-point decrease in CPRS-R and BRIEF-P T-scores among groups with low cord blood lead and patella lead (P1-P25). Conclusions Children experiencing high maternal self-esteem during toddlerhood were less likely to develop inattention behavior at school-age. Prenatal lead exposure may play a role in attenuating this protective effect. PMID:26047683

  15. Prenatal Lead Exposure Modifies the Impact of Maternal Self-Esteem on Children's Inattention Behavior.

    PubMed

    Xu, Jian; Hu, Howard; Wright, Rosalind; Sánchez, Brisa N; Schnaas, Lourdes; Bellinger, David C; Park, Sung Kyun; Martínez, Sandra; Hernández-Avila, Mauricio; Téllez-Rojo, Martha Maria; Wright, Robert O

    2015-08-01

    To prospectively evaluate the association of maternal self-esteem measured when their offspring were toddlers with the subsequent development of attention deficit hyperactivity disorder (ADHD)-like behavior in their school-age offspring and the potential modifying effects of prenatal lead exposure. We evaluated a subsample of 192 mother-child pairs from a long-running birth-cohort project that enrolled mothers in Mexico from 1994-2011. Prenatal lead exposure was assessed using cord blood lead and maternal bone lead around delivery (tibia and patella lead, measured by K-x-ray-fluorescence). When children were 2 years old, maternal self-esteem was measured using the Coopersmith Self-Esteem Inventory. When children were 7-15 years old, children's blood lead levels and ADHD symptoms were assessed, and Conners' Parent Rating Scale-Revised and Behavior Rating Inventory of Executive Function-Parent Form were used as measures of ADHD-like behavior. Adjusting for family economic status, marital status, maternal education and age, child's age and sex, and children's current blood lead levels, increased maternal self-esteem was associated with reduced child inattention behavior. Compared with those among high prenatal lead exposure (P25-P100), this association was stronger among low prenatal lead exposure groups (P1-P25, P values for the interaction effects between prenatal lead exposure and maternal self-esteem levels of <.10). Each 1-point increase in maternal self-esteem scores was associated with 0.6- to 1.3-point decrease in Conners' Parent Rating Scale-Revised and Behavior Rating Inventory of Executive Function-Parent Form T-scores among groups with low cord blood lead and patella lead (P1-P25). Children experiencing high maternal self-esteem during toddlerhood were less likely to develop inattention behavior at school age. Prenatal lead exposure may play a role in attenuating this protective effect. Copyright © 2015 Elsevier Inc. All rights reserved.

  16. Exploring Childhood Lead Exposure through GIS: A Review of the Recent Literature

    PubMed Central

    Akkus, Cem; Ozdenerol, Esra

    2014-01-01

    Childhood exposure to lead remains a critical health control problem in the US. Integration of Geographic Information Systems (GIS) into childhood lead exposure studies significantly enhanced identifying lead hazards in the environment and determining at risk children. Research indicates that the toxic threshold for lead exposure was updated three times in the last four decades: 60 to 30 micrograms per deciliter (µg/dL) in 1975, 25 µg/dL in 1985, and 10 µb/dL in 1991. These changes revealed the extent of lead poisoning. By 2012 it was evident that no safe blood lead threshold for the adverse effects of lead on children had been identified and the Center for Disease Control (CDC) currently uses a reference value of 5 µg/dL. Review of the recent literature on GIS-based studies suggests that numerous environmental risk factors might be critical for lead exposure. New GIS-based studies are used in surveillance data management, risk analysis, lead exposure visualization, and community intervention strategies where geographically-targeted, specific intervention measures are taken. PMID:24945189

  17. Lead Exposure in Free-Flying Turkey Vultures Is Associated with Big Game Hunting in California

    PubMed Central

    Kelly, Terra R.; Johnson, Christine K.

    2011-01-01

    Predatory and scavenging birds are at risk of lead exposure when they feed on animals injured or killed by lead ammunition. While lead ammunition has been banned from waterfowl hunting in North America for almost two decades, lead ammunition is still widely used for hunting big game and small game animals. In this study, we evaluated the association between big game hunting and blood lead concentration in an avian scavenger species that feeds regularly on large mammals in California. We compared blood lead concentration in turkey vultures within and outside of the deer hunting season, and in areas with varying wild pig hunting intensity. Lead exposure in turkey vultures was significantly higher during the deer hunting season compared to the off-season, and blood lead concentration was positively correlated with increasing wild pig hunting intensity. Our results link lead exposure in turkey vultures to deer and wild pig hunting activity at these study sites, and we provide evidence that spent lead ammunition in carrion poses a significant risk of lead exposure to scavengers. PMID:21494326

  18. Lead exposure in free-flying turkey vultures is associated with big game hunting in California.

    PubMed

    Kelly, Terra R; Johnson, Christine K

    2011-04-06

    Predatory and scavenging birds are at risk of lead exposure when they feed on animals injured or killed by lead ammunition. While lead ammunition has been banned from waterfowl hunting in North America for almost two decades, lead ammunition is still widely used for hunting big game and small game animals. In this study, we evaluated the association between big game hunting and blood lead concentration in an avian scavenger species that feeds regularly on large mammals in California. We compared blood lead concentration in turkey vultures within and outside of the deer hunting season, and in areas with varying wild pig hunting intensity. Lead exposure in turkey vultures was significantly higher during the deer hunting season compared to the off-season, and blood lead concentration was positively correlated with increasing wild pig hunting intensity. Our results link lead exposure in turkey vultures to deer and wild pig hunting activity at these study sites, and we provide evidence that spent lead ammunition in carrion poses a significant risk of lead exposure to scavengers.

  19. The conceptual structure of the integrated exposure uptake biokinetic model for lead in children.

    PubMed Central

    White, P D; Van Leeuwen, P; Davis, B D; Maddaloni, M; Hogan, K A; Marcus, A H; Elias, R W

    1998-01-01

    The integrated exposure uptake biokinetic model for lead in children was developed to provide plausible blood lead distributions corresponding to particular combinations of multimedia lead exposure. The model is based on a set of equations that convert lead exposure (expressed as micrograms per day) to blood lead concentration (expressed as micrograms per deciliter) by quantitatively mimicking the physiologic processes that determine blood lead concentration. The exposures from air, food, water, soil, and dust are modeled independently by several routes. Amounts of lead absorbed are modeled independently for air, food, water, and soil/dust, then combined as a single input to the blood plasma reservoir of the body. Lead in the blood plasma reservoir, which includes extracellular fluids, is mathematically allocated to all tissues of the body using age-specific biokinetic parameters. The model calculation provides the estimate for blood lead concentration for that age. This value is treated as the geometric mean of possible values for a single child, or the geometric mean of expected values for a population of children exposed to the same lead concentrations. The distribution of blood lead concentrations about this geometric mean is estimated using a geometric standard deviation, typically 1.6, derived from the analysis of well-conducted community blood studies. PMID:9860910

  20. The effect of occupational exposure to lead on the non-enzymatic antioxidant system.

    PubMed

    Dobrakowski, Michał; Zalejska-Fiolka, Jolanta; Wielkoszyński, Tomasz; Świętochowska, Elżbieta; Kasperczyk, Sławomir

    2014-01-01

    The role of non-enzymatic antioxidants, such as uric acid, albumin, bilirubin, and α-tocopherol, in lead poisoning remains unclear. Therefore, the aim of the study was to explore the association between occupational exposure to lead and non-enzymatic antioxidant concentrations in serum and plasma. The study population consisted of 278 healthy male employees of lead-zinc plants, with 129 workers classified as having low lead exposure (blood lead level - PbB = 20-39.9 µg/dl) and 149 workers classified as having high lead exposure (PbB = 40-59.8 µg/dl). The control group was composed of 73 healthy male administrative workers. No one from this group had blood lead level or zinc protoporphyrin (ZPP) level greater than normal levels, being 10 µ/dl and 2.5 µg/g of hemoglobin, respectively. In addition to the levels of PbB and ZPP, serum levels of uric acid (UA), albumin, thiol groups of albumin, and bilirubin were determined. The ferric reducing ability of plasma (FRAP) and the plasma level of α-tocopherol were also evaluated. Lead exposure indices were significantly elevated in the examined subgroups as compared with the controls. Serum uric acid levels were significantly elevated in both subgroups, particularly in the group with high exposure. Serum bilirubin concentration was significantly elevated in the group with high exposure compared with the control group, while in the group with low exposure, it showed only a non-significant trend towards an increase. In contrast, ferric-reducing ability of plasma was not significantly greater in the examined subgroups as compared with the control group. Nevertheless, levels of albumin, thiol groups of albumin, and α-tocopherol levels were significantly decreased in the exposed subgroups compared with the control group. Occupational exposure to lead interferes with the blood non-enzymatic antioxidant system.

  1. Lead exposure in starter battery production: investigation of the correlation between air lead and blood lead levels.

    PubMed

    Kentner, M; Fischer, T

    1994-01-01

    The threshold limit value (TLV) for lead (in Germany, the MAK value) is based on a certain blood lead concentration (in Germany BAT value = biological tolerance value for working materials) that is not to be exceeded; thereby a statistically significant association between air lead (PbA) and blood lead (PbB) is assumed. On the basis of a 10-year period of (1982-1991) biological and ambient monitoring of 134 battery factory staff and their workplaces, a PbA/PbB correlation with the regression equation PbB = 62.183 + 21.242 x Log 10 (PbA) (n = 1089, r = 0.274, P < 0.001) was calculated. These results are in line with those of several other investigations. The shape of the regression curve and the wide scattering of values led to the assumption that PbA values above the MAK value (0.1 mg/m3) do not necessarily result in increased PbB values. Similarly, PbA values lower than the MAK value do not guarantee PbB levels below the BAT value in every case. These observations are influenced by numerous confounders and intervening variables. It is concluded that lowering MAK values as a consequence of lowering BAT values is not mandatory.

  2. Cadmium but not lead exposure affects Xenopus laevis fertilization and embryo cleavage.

    PubMed

    Slaby, Sylvain; Lemière, Sébastien; Hanotel, Julie; Lescuyer, Arlette; Demuynck, Sylvain; Bodart, Jean-François; Leprêtre, Alain; Marin, Matthieu

    2016-08-01

    Among the toxicological and ecotoxicological studies, few have investigated the effects on germ cells, gametes or embryos, while an impact at these stages will result in serious damage at a population level. Thus, it appeared essential to characterize consequences of environmental contaminant exposures at these stages. Therefore, we proposed to assess the effects of exposure to cadmium and lead ions, alone or in a binary mixture, on early stages of Xenopus laevis life cycle. Fertilization and cell division during segmentation were the studied endpoints. Cadmium ion exposures decreased in the fertilization rates in a concentration-dependent manner, targeting mainly the oocytes. Exposure to this metal ions induced also delays or blockages in the embryonic development. For lead ion exposure, no such effect was observed. For the exposure to the mixture of the two metal ions, concerning the fertilization success, we observed results similar to those obtained with the highest cadmium ion concentration.

  3. Childhood lead toxicity and impaired release of thyrotropin-stimulating hormone

    SciTech Connect

    Huseman, C.A.; Moriarty, C.M.; Angle, C.R.

    1987-04-01

    Decreased stature of children is epidemiologically associated with increased blood lead independent of multiple socioeconomic and nutritional variables. Since endocrine dysfunction occurs in adult lead workers, they studied two girls, 2 years of age, before and after calcium disodium edetate chelation for blood leads (PbB) of 19-72 ..mu..g/dl. The height of both children had crossed from the 50th to below the 10th percentile during the course of chronic lead toxicity. Basal free T/sub 4/, T/sub 4/, T/sub 3/, cortisol, somatomedin C, and sex steroids were normal. A decrease in the growth hormone response and elevation of basal prolcatin and gonadotropins were noted in one. Both children demonstrated blunted thyrotropin-stimulating hormone (TSH) responses to thyrotropin-releasing hormone (TRH) in six of seven challenges. This prompted in vitro studies of cultured cells from rat pituitarities. After incubation of pituitary cells with 0.1-10 ..mu..M Pb/sup 2 +/ for 2 hr, followed by the addition of TRH, there was a dose-dependent inhibition of TSH release Lead did not interfere with the assay of TSH. To investigate the interaction of lead and calcium, /sup 45/Ca/sup 2 +/ kinetic analyses were done on rat pituitary slices after 1 hr incubation with 1.0 ..mu..M lead. The impaired late efflux was consistent with a decrease in the size and exchangeability of the tightly bound pool of intracellular microsomal or mitochondrial calcium. The rat pituitary cell model provides a model for the decreased TSH release of lead poisoning, supports the biological plausibility of a neuroendocrine effect on growth, and suggests that interference with calcium-mediated intracellular responses is a basic mechanism of lead toxicity.

  4. An experimental study of deep brain stimulation lead fracture: possible fatigue mechanisms and prevention approach.

    PubMed

    Jiang, Changqing; Mo, Xiaolong; Dong, Yantao; Meng, Fangang; Hao, Hongwei; Zhang, Jianguo; Feng, Xiqiao; Li, Luming

    2015-06-01

    Lead fracture is a common and troublesome hardware-related complication in deep brain stimulation therapy. Frequent cervical movements are suspected as the main cause, but the underlying mechanisms are still unclear. We propose the integrity of the helical structure of the lead wires is important and conduct systematic experiments to demonstrate this. We aim to provide a new view on how lead fracture takes place. Flexural fatigue tests were conducted on intact and stretched lead wires with a custom-made testing machine. Number of cycles until failure was recorded as the fatigue life, and the fracture morphology was observed under optical and scanning electron microscopes. The fatigue life of the lead wires showed dramatic decline with the severity of deformation, from 434,112 ± 10,277 cycles for an intact specimen down to 19,435 ± 2,622 cycles for a specimen elongated by approximately 20%. The morphology of the fractures revealed characteristic beach marks and striations indicating a fatigue failure. We demonstrate that integrity of the helical structure of the wires is crucial to the fatigue performance of the lead. Although the results cannot be directly extrapolated to human subjects, they suggest a possible lead fracture mechanism. The implanted lead may undergo deformation due to large-amplitude motions (e.g., falls) and develop fracture due to the deterioration in fatigue resistance, especially when it is placed at or migrates to the neck. It may be possible to effectively protect the lead by using certain surgical techniques during implantation, such as placing the connector on the calvaria or in a drilled trough at the retroauricular region with reliable fixation. © 2014 International Neuromodulation Society.

  5. DEVELOPMENTAL EXPOSURE TO A THYROID DISRUPTING CHEMICAL STIMULATES PHAGOCYTOSIS IN JUVENILE SPRAGUE-DAWLEY RATS

    EPA Science Inventory

    Developmental Exposure to a Thyroid Disrupting Chemical Stimulates Phagocytosis in Juvenile Sprague-Dawley Rats.
    AA Rooney1, R Matulka2, and R Luebke3. 1NCSU/US EPA CVM, Department of Anatomy, Physiological Sciences and Radiology, Raleigh, NC;2UNC Department of Toxicology, Cha...

  6. DEVELOPMENTAL EXPOSURE TO A THYROID DISRUPTING CHEMICAL STIMULATES PHAGOCYTOSIS IN JUVENILE SPRAGUE-DAWLEY RATS

    EPA Science Inventory

    Developmental Exposure to a Thyroid Disrupting Chemical Stimulates Phagocytosis in Juvenile Sprague-Dawley Rats.
    AA Rooney1, R Matulka2, and R Luebke3. 1NCSU/US EPA CVM, Department of Anatomy, Physiological Sciences and Radiology, Raleigh, NC;2UNC Department of Toxicology, Cha...

  7. Perinatal lead exposure affects nitric oxide and cyclooxygenase pathways in aorta of weaned rats.

    PubMed

    Grizzo, Larissa Tercilia; Cordellini, Sandra

    2008-05-01

    Perinatal Pb exposure may modulate arterial tone through nitric oxide (NO) and cyclooxygenase products. To investigate this, Wistar dams received 1000 ppm of Pb or sodium acetate (control) in drinking water during pregnancy and lactation. Curves were constructed in phenylephrine-precontracted intact and/or denuded rings of thoracic aortas of weaned (23-day-old) male pups from their responses to N(omega)-nitro-L-arginine methyl ester (L-NAME, NO synthase inhibitor) and ACh in the absence or presence of indomethacin (10(-5)M, cyclooxygenase inhibitor) or L-NAME (3 x 10(-7)M and 3 x 10(-4)M). Blood lead concentration and systolic blood pressure (SBP) were higher in intoxicated than control pups (blood lead microg/dl: control < 3.0, Pb 58.7 +/- 6.5*; SBP mmHg: control 111.4 +/- 2.3, Pb 135.5 +/- 2.4*). In L-NAME-treated rings maximal responses increased in Pb-exposed rats, and were higher in intact than in denuded aortas (contraction [% of phenylephrine] intact: control 184.3 +/- 23.7, Pb 289.1 +/- 18.3*; denuded: control 125.1 +/- 4.5, Pb 154.8 +/- 13.3*). ACh-induced relaxation in intact aortas from Pb-exposed rats presented rightward shift in L-NAME presence (EC50 x 10(-7)M: control 1.32 [0.33-5.18], Pb 4.88 [3.56-6.69]*) but moved left under indomethacin (EC50 x 10(-7)M: control 8.95 [3.47-23.07], Pb 0.97 [0.38-2.43]*). *p < 0.05 significant relative to the respective control; N = 7-9. Endothelium removal abolished ACh-induced relaxation. Perinatal Pb exposure caused hypertension associated with alterations in the production and/or release of basal and stimulated endothelium-derived relaxing factors-NO and constricting cyclooxygenase products. These findings may help explain the contribution of NO and cyclooxygenase products to the etiology and/or maintenance of Pb-induced hypertension and could ultimately lead to therapeutic advantages in plumbism.

  8. Formal recycling of e-waste leads to increased exposure to toxic metals: an occupational exposure study from Sweden.

    PubMed

    Julander, Anneli; Lundgren, Lennart; Skare, Lizbet; Grandér, Margaretha; Palm, Brita; Vahter, Marie; Lidén, Carola

    2014-12-01

    Electrical and electronic waste (e-waste) contains multiple toxic metals. However, there is currently a lack of exposure data for metals on workers in formal recycling plants. The objective of this study was to evaluate workers' exposure to metals, using biomarkers of exposure in combination with monitoring of personal air exposure. We assessed exposure to 20 potentially toxic metals among 55 recycling workers and 10 office workers at three formal e-waste recycling plants in Sweden. Workers at two of the plants were followed-up after 6 months. We collected the inhalable fraction and OFC (37-mm) fraction of particles, using personal samplers, as well as spot samples of blood and urine. We measured metal concentrations in whole blood, plasma, urine, and air filters using inductively coupled plasma-mass spectrometry following acid digestion. The air sampling indicated greater airborne exposure, 10 to 30 times higher, to most metals among the recycling workers handling e-waste than among the office workers. The exposure biomarkers showed significantly higher concentrations of chromium, cobalt, indium, lead, and mercury in blood, urine, and/or plasma of the recycling workers, compared with the office workers. Concentrations of antimony, indium, lead, mercury, and vanadium showed close to linear associations between the inhalable particle fraction and blood, plasma, or urine. In conclusion, our study of formal e-waste recycling shows that workers performing recycling tasks are exposed to multiple toxic metals. Copyright © 2014. Published by Elsevier Ltd.

  9. Lead Exposures in U.S. Children, 2008: Implications for Prevention

    PubMed Central

    Levin, Ronnie; Brown, Mary Jean; Kashtock, Michael E.; Jacobs, David E.; Whelan, Elizabeth A.; Rodman, Joanne; Schock, Michael R.; Padilla, Alma; Sinks, Thomas

    2008-01-01

    Objective We reviewed the sources of lead in the environments of U.S. children, contributions to children’s blood lead levels, source elimination and control efforts, and existing federal authorities. Our context is the U.S. public health goal to eliminate pediatric elevated blood lead levels (EBLs) by 2010. Data sources National, state, and local exposure assessments over the past half century have identified risk factors for EBLs among U.S. children, including age, race, income, age and location of housing, parental occupation, and season. Data extraction and synthesis Recent national policies have greatly reduced lead exposure among U.S. children, but even very low exposure levels compromise children’s later intellectual development and lifetime achievement. No threshold for these effects has been demonstrated. Although lead paint and dust may still account for up to 70% of EBLs in U.S. children, the U.S. Centers for Disease Control and Prevention estimates that ≥30% of current EBLs do not have an immediate lead paint source, and numerous studies indicate that lead exposures result from multiple sources. EBLs and even deaths have been associated with inadequately controlled sources including ethnic remedies and goods, consumer products, and food-related items such as ceramics. Lead in public drinking water and in older urban centers remain exposure sources in many areas. Conclusions Achieving the 2010 goal requires maintaining current efforts, especially programs addressing lead paint, while developing interventions that prevent exposure before children are poisoned. It also requires active collaboration across all levels of government to identify and control all potential sources of lead exposure, as well as primary prevention. PMID:18941567

  10. EPA Settlements Help Protect Public Against Health Hazards from Lead Exposure

    EPA Pesticide Factsheets

    WASHINGTON -- The U.S. Environmental Protection Agency (EPA) today announced 75 enforcement actions from the past year that require renovation contractors and training providers to protect people from harmful exposure to lead dust and debris, as req

  11. Prospective associations between childhood low-level lead exposure and adult mental health problems: the Port Pirie cohort study.

    PubMed

    McFarlane, Alexander C; Searle, Amelia K; Van Hooff, Miranda; Baghurst, Peter A; Sawyer, Michael G; Galletly, Cherrie; Sim, Malcolm R; Clark, Levina S

    2013-12-01

    Low-level environmental lead exposure during childhood is associated with poorer emotional/behavioural functioning in later childhood and adolescence. Scarce research has examined whether these apparent effects persist into adulthood. This study is the first to examine prospective associations between lead exposure across early childhood and several common adult mental health problems. Childhood data (including blood lead concentrations) and adult data (from mental health questionnaires and psychiatric interviews) were available for 210 participants (44% males, mean age=26.3 years) from the Port Pirie cohort study (1979-1982 birth cohort). Participants had a mean childhood (to 7 years) average blood lead concentration of 17.2μg/dL. Among females, childhood blood lead showed small significant positive associations with lifetime diagnoses of drug and alcohol abuse and social phobia, and with anxiety, somatic and antisocial personality problems. For example: for a 10μg/dL blood lead increase, females were 2.84 times (95% CI 1.10, 7.30) more likely to have an alcohol abuse diagnosis. However, adjustment for childhood covariates - particularly stimulation within the home environment - rendered these associations non-significant. No significant or sizeable unadjusted or adjusted associations were seen for males. The associations between early lead exposure and emotional/behavioural functioning in children might persist into adulthood, at least for females. However, it is unclear whether such results arise from residual confounding, or other mechanisms. Interventions that focus on improving the childhood home environment may have a long-term positive impact on adult mental health outcomes. However, more prospective research using large and representative samples is needed to substantiate these results.

  12. Early Childhood Lead Exposure and Academic Achievement: Evidence From Detroit Public Schools, 2008–2010

    PubMed Central

    Baker, Harolyn W.; Tufts, Margaret; Raymond, Randall E.; Salihu, Hamisu; Elliott, Michael R.

    2013-01-01

    Objectives. We assessed the long-term effect of early childhood lead exposure on academic achievement in mathematics, science, and reading among elementary and junior high school children. Methods. We linked early childhood blood lead testing surveillance data from the Detroit Department of Health and Wellness Promotion to educational testing data from the Detroit, Michigan, public schools. We used the linked data to investigate the effect of early childhood lead exposure on academic achievement among school-aged children, both marginally and adjusted for grade level, gender, race, language, maternal education, and socioeconomic status. Results. High blood lead levels before age 6 years were strongly associated with poor academic achievement in grades 3, 5, and 8. The odds of scoring less than proficient for those whose blood lead levels were greater than 10 micrograms per deciliter were more than twice the odds for those whose blood lead levels were less than 1 micrograms per deciliter after adjustment for potential confounders. Conclusions. Early childhood lead exposure was negatively associated with academic achievement in elementary and junior high school, after adjusting for key potential confounders. The control of lead poisoning should focus on primary prevention of lead exposure in children and development of special education programs for students with lead poisoning. PMID:23327265

  13. Determination of exposure to lead of subjects from southwestern Poland by human hair analysis.

    PubMed

    Michalak, Izabela; Wołowiec, Paulina; Chojnacka, Katarzyna

    2014-04-01

    The aim of the present work was to investigate the exposure to lead from various sources by investigation of mineral composition of human scalp hair. The research was carried out on hair sampled from 267 young adults living in Wrocław (southwest Poland). The effect of the place of residence, diet, and lifestyle on lead content in hair was examined by inductively coupled plasma optical emission spectrometry (ICP-OES). Lead was determined at the wavelength 220.353 nm. These outcomes were reached by linking the results of lead level in hair with the results of questionnaire survey. The mean lead level in hair of the whole examined population was 2.01 ± 2.10 mg kg(-1). Lead can enter the human body mainly by inhalation and gastrointestinal absorption. It was found that consuming cheese, fish, and lettuce caused increased level of lead in hair. On the other hand, drinking of milk, tea, coffee, or lemon resulted in decreased content of lead in hair. Additional source of exposure to lead could be cigarette smoking, distance to the traffic road, painting the walls, amalgam filling. Based on the results, it can be concluded that exposure to lead can occur mainly from eating habits and environmental exposure.

  14. Cumulative Lead Exposure and Age-related Hearing Loss: The VA Normative Aging Study

    PubMed Central

    Park, Sung Kyun; Elmarsafawy, Sahar; Mukherjee, Bhramar; Spiro, Avron; Vokonas, Pantel S.; Nie, Huiling; Weisskopf, Marc G.; Schwartz, Joel; Hu, Howard

    2010-01-01

    Although lead has been associated with hearing loss in occupational settings and in children, little epidemiologic research has been conducted on the impact of cumulative lead exposure on age-related hearing loss in the general population. We determined whether bone lead levels, a marker of cumulative lead exposure, are associated with decreased hearing ability in 448 men from the Normative Aging Study, seen between 1962 and 1996 (2,264 total observations). Air conduction hearing thresholds were measured at 0.25 to 8 kHz and pure tone averages (PTA) (mean of 0.5, 1, 2 and 4 kHz) were computed. Tibia and patella lead levels were measured using K x-ray fluorescence between 1991 and 1996. In cross-sectional analyses, after adjusting for potential confounders including occupational noise, patella lead levels were significantly associated with poorer hearing thresholds at 2, 3, 4, 6 and 8 kHz and PTA. The odds of hearing loss significantly increased with patella lead levels. We also found significant positive associations between tibia lead and the rate change in hearing thresholds at 1, 2, and 8 kHz and PTA in longitudinal analyses. Our results suggest that chronic low-level lead exposure may be an important risk factor for age-related hearing loss and reduction of lead exposure could help prevent or delay development of age-related hearing loss. PMID:20638461

  15. Lessons from a Danish study on neuropsychological impairment related to lead exposure

    SciTech Connect

    Grandjean, P.; Lyngbye, T. ); Hansen, O.N. )

    1991-08-01

    Serious problems emerge when evaluating evidence on lead neurotoxicity in children. The extent of these problems and ways to control them were explored in a study of 1291 children from the first class in the schools of Aarhus municipality, Denmark. The lead retention in circumpulpal dentin in shed deciduous teeth was used as an indicator of cumulated lead exposure; it correlated most strongly with traffic density at the residence of each family and at the day-care institutions. In a nested case-control group selected on the basis of dentin lead concentrations, 29 of 200 children had encountered obstetrical complications and other medical risks for neurobehavioral dysfunction; these children primarily belonged to the low-lead group. As lead-related neurobehavioral effects are nonspecific, inclusion of these children in the data analysis would therefore have distorted the results toward the null hypothesis. Children from the high-lead group who had experienced neonatal jaundice showed impaired performance when compared to other high-lead children; this finding may suggest a synergistic effect. The Bender gestalt test scored by the Goettingen system was the test that was most sensitive to lead exposure. The conclusion that neurobehavioral effects can be caused by the relatively low lead exposures in Denmark may not be surprising, as current exposures to this toxic metal greatly exceed the prepollution levels to which the human body originally adapted.

  16. Prenatal or lactational exposure of male rats to lead acetate. Effect on reproductive function

    SciTech Connect

    Thoreux-Manlay, A.; Pinon-Lataillade, G.; Coffigny, H.; Masse, R.; Soufir, J.C.

    1995-02-01

    Lead is an environmental pollutant which has received much attention, partly because of the particular sensitivity of children to this element. As regards the consequences of exposure to lead during fetal life or childhood, epidemiological studies have so far focused on its neuropsychological effects and little is known about the consequences of fetal or childhood exposure for reproduction. With respect to animals, the reproductive toxicity of lead in males exposed during prenatal life or the suckling period has only been considered in a few studies. Four such studies concerned the rat, the most current model of lead toxicity for male reproduction; two of studies considered the long term effects (i.e. during adulthood) of moderate in utero lead exposure, another covered the prenatal and neonatal periods and focused on the possible impact of lead intoxication on steriodogenesis before weaning, while the remaining study dealt with pituitary hormone level at the end of lead gavage in newborns. None of these investigations compared the effects of exposure during prenatal life to those of exposure via lactation, or the early effects (at about weaning time) to the long-term consequences during adulthood. Because of the paucity of data on these points, we conducted two experiments: in one, rats were exposed to lead prenatally, and in the other via maternal milk. In both cases male reproductive function at weaning and adulthood was examined. 12 refs., 1 fig., 2 tabs.

  17. Relative exposure of children to lead from dust and drinking water.

    PubMed

    Alexander, L M; Heaven, A; Delves, H T; Moreton, J; Trenouth, M J

    1993-01-01

    The Blackpool, Wyre and Fylde Health Authority, in the North West of England, could be described as a "low-level lead exposure area." Primary sources of lead exposure are atmospheric fallout (both indoors and outdoors) and potable water consumption. Deciduous teeth were collected from children living in this area as were water samples and outdoor dust samples. Both total lead concentrations and 206Pb:207Pb ratios were determined for a defined subset of teeth. Significant differences in the total lead concentrations were found for teeth collected from children resident in different targeted areas (i.e., Blackpool, Fleetwood, and Garstang). No significant differences were found between the total lead concentrations or the 206Pb:207Pb ratios from dust and water samples in these areas. Examination of the 206Pb:207Pb ratios for dust, water, and teeth obtained from each area separately revealed differing patterns of exposure to lead. Determination of 206Pb:207Pb ratios, in addition to total lead concentrations, enabled the differences in sources of exposure to be identified in these communities. The authors conclude that isotopic analyses are an important aspect of community survey work, and these analyses can be helpful in accurately targeting intervention strategies aimed at reducing exposure to lead.

  18. Fetal Lead Exposure at Each Stage of Pregnancy as a Predictor of Infant Mental Development

    PubMed Central

    Hu, Howard; Téllez-Rojo, Martha María; Bellinger, David; Smith, Donald; Ettinger, Adrienne S.; Lamadrid-Figueroa, Héctor; Schwartz, Joel; Schnaas, Lourdes; Mercado-García, Adriana; Hernández-Avila, Mauricio

    2006-01-01

    Background The impact of prenatal lead exposure on neurodevelopment remains unclear in terms of consistency, the trimester of greatest vulnerability, and the best method for estimating fetal lead exposure. Objective We studied prenatal lead exposure’s impact on neurodevelopment using repeated measures of fetal dose as reflected by maternal whole blood and plasma lead levels. Methods We measured lead in maternal plasma and whole blood during each trimester in 146 pregnant women in Mexico City. We then measured umbilical cord blood lead at delivery and, when offspring were 12 and 24 months of age, measured blood lead and administered the Bayley Scales of Infant Development. We used multivariate regression, adjusting for covariates and 24-month blood lead, to compare the impacts of our pregnancy measures of fetal lead dose. Results Maternal lead levels were moderately high with a first-trimester blood lead mean (± SD) value of 7.1 ± 5.1 μg/dL and 14% of values ≥10 μg/dL. Both maternal plasma and whole blood lead during the first trimester (but not in the second or third trimester) were significant predictors (p < 0.05) of poorer Mental Development Index (MDI) scores. In models combining all three trimester measures and using standardized coefficients, the effect of first-trimester maternal plasma lead was somewhat greater than the effect of first-trimester maternal whole blood lead and substantially greater than the effects of second- or third-trimester plasma lead, and values averaged over all three trimesters. A 1-SD change in first-trimester plasma lead was associated with a reduction in MDI score of 3.5 points. Postnatal blood lead levels in the offspring were less strongly correlated with MDI scores. Conclusions Fetal lead exposure has an adverse effect on neurodevelopment, with an effect that may be most pronounced during the first trimester and best captured by measuring lead in either maternal plasma or whole blood. PMID:17107860

  19. Lead Exposure Risk from Trash Ingestion by the Endangered California Condor (Gymnogyps californianus).

    PubMed

    Finkelstein, Myra E; Brandt, Joseph; Sandhaus, Estelle; Grantham, Jesse; Mee, Allan; Schuppert, Patricia Jill; Smith, Donald R

    2015-10-01

    Lead poisoning from ingestion of spent lead ammunition is one of the greatest threats to the recovery of California Condors (Gymnogyps californianus) in the wild. Trash ingestion by condors is well documented, yet the extent that trash presents a lead exposure risk is unknown. We evaluated 1,413 trash items collected from condor nest areas and nestlings in the Transverse Range of Ventura County, California, US, from 2002 to 2008, for their potential as a lead exposure risk to condors. We visually identified 71 items suspected to contain sufficient lead to be of toxicologic concern. These items were leached with weak acid and analyzed for lead. Twenty-seven of the 71 leached items (~2% of the 1,413 items) were "lead containing" based on criteria of a leachate lead concentration >1 μg/mL, with the majority of these items (22; 81% of the 27 lead items) being ammunition related (e.g., spent bullet casings and jacketed bullets). Only three of the 1,413 items collected were lead containing but were clearly not ammunition related; the other two lead-containing items were unidentified. Our results suggest that trash ingestion of nonammunition items does not pose a significant lead exposure risk to the California Condor population in California.

  20. Recruitment and blocking properties of the CardioFit stimulation lead

    NASA Astrophysics Data System (ADS)

    Ahilea Anholt, Tamar; Ayal, Shai; Goldberg, Joshua A.

    2011-06-01

    The CardioFit vagal stimulation system has been developed as a proposed therapy for congestive heart failure (CHF). CardioFit is to be implanted in several hundred CHF patients enrolled in the INOVATE-HF clinical trial, an FDA approved study. The CardioFit stimulation lead (CSL), which is a cuff electrode that delivers stimulation pulses to the right cervical vagus, was designed to recruit efferent cardiac vagal fibers while minimizing unwanted recruitment of other fibers. This paper presents the CSL and measurements of its recruiting and blocking properties when placed on isolated porcine vagus nerves maintained at an elevated temperature in oxygenated artificial cerebrospinal fluid. Using charge balanced quasi-trapezoidal pulses driven through the CSL, we show in eight out of nine nerves a 63% ± 13% (mean ± SD) unidirectional attenuation of the A-fiber compound action potential attained at a current of 3.0 ± 0.8 mA. The threshold for the activation of A- and B-fibers was found to be 0.3 ± 0.17 mA and 2.5 ± 1.1 mA, respectively. The results presented here should help to guide the optimal parameters used in the upcoming deployment of the CardioFit system.

  1. Influence of occupational low-level lead exposure on renal parameters

    SciTech Connect

    Verschoor, M.; Wibowo, A.; Herber, R.; van Hemmen, J.; Zielhuis, R.

    1987-01-01

    The influence of lead exposure on renal function was examined. In 155 lead workers and 126 control workers, lead in blood (PbB) and zinc protoporphyrin in blood (ZPP) were measured as indicators of exposure to lead; various proteins in urine were measured as parameters of renal functions. Regression and matched-pair analyses suggest that tubular parameters may be more influenced by lead exposure than glomerular parameters. Changes in renal function parameters may already occur at PbB levels below 3 mumol/liter (600 micrograms/liter). The excretion of N-acetyl-beta-D-glucosaminidase appears to be the most consistent and sensitive parameter of an early effect on the tubular function.

  2. Progressive supranuclear palsy-like parkinsonism resulting from occupational exposure to lead sulphate batteries.

    PubMed

    Sanz, P; Nogué, S; Vilchez, D; Vilchez, J; Casal, A; Logroscino, G

    2007-01-01

    A 53-year-old man who had worked for 17 years manufacturing car batteries, with overt exposure to lead, developed a clinical picture initially characterized by signs of parkinsonism, followed by atypical signs such as loss of memory, reduction of eye movement, dysarthria, chorea-like dyskinesia and sexual impotence. The diagnosis of atypical parkinsonism was eventually changed to progressive supranuclear palsy-like parkinsonism. The patient was treated with various anti-Parkinson's disease drugs, including levodopa, with modest improvement. The symptoms deteriorated progressively, leading to permanent occupational disability with noticeable limitation of daily activities. Toxicological studies revealed abnormally high blood levels of lead. Discontinuation of lead exposure was followed first by clinical stabilization and then steady improvement. This case confirms recent reports that link exposure to lead and its compounds with degenerative diseases of the central nervous system, such as Parkinson's disease.

  3. Low level lead exposure in the prenatal and early preschool periods: early preschool development.

    PubMed

    Ernhart, C B; Morrow-Tlucak, M; Marler, M R; Wolf, A W

    1987-01-01

    The hypothesis that low level lead exposure in the fetal and early preschool years is related to neuropsychological deficit was examined in a prospective study of child development. We also tested the hypothesis of reverse causality, i.e., that lead level is a function of prior developmental status. Fetal lead exposure was measured in maternal and cord blood while preschool lead level was measured in venous blood samples at ages six months, two years and three years. These blood lead measures (PbB) were related to concurrent and ensuing scores on developmental measures at six months, one year, two years, and three years. With statistical control of covariate measures (age, sex, race, birth weight, birth order, gestational exposure to other toxic substances, maternal intelligence, and several indicators of the quality of the caretaking environment) as well as potentially confounding risk factors (gestational exposure to alcohol and other toxic substances), most statistically significant associations of PbB with concurrent and later development were completely attenuated. Effects of lead exposure, significant or not, were not consistent in direction. In reverse-causality analyses, PbB was not related significantly to prior measures of developmental retardation or acceleration. It was concluded that the relationship of lead level and measures of development in these early years was primarily a function of the dependence of each on the quality of the caretaking environment.

  4. Failure of EPA`s IEUBK model to identify children at risk from lead exposure

    SciTech Connect

    Coomes, R.M.

    1996-12-31

    Modeled blood lead concentrations derived from EPA`s Integrated Exposure Uptake Biokinetic Model LEAD99 (Model) were compared to measured blood lead concentrations for two populations of children living in Colorado mining communities. The study areas were Clear Creek and California Gulch. Both studies presented paired blood lead level measurements and environmental media lead concentrations. The data for this paper were obtained from the Colorado Department of Health and publicly-available submissions made to EPA Region VIII. EPA has used the Model to identify soil lead concentrations that are protective of individual children.

  5. Economic costs of childhood lead exposure in low- and middle-income countries.

    PubMed

    Attina, Teresa M; Trasande, Leonardo

    2013-09-01

    Children's blood lead levels have declined worldwide, especially after the removal of lead in gasoline. However, significant exposure remains, particularly in low- and middle-income countries. To date, there have been no global estimates of the costs related to lead exposure in children in developing countries. Our main aim was to estimate the economic costs attributable to childhood lead exposure in low- and middle-income countries. We developed a regression model to estimate mean blood lead levels in our population of interest, represented by each 1-year cohort of children < 5 years of age. We used an environmentally attributable fraction model to estimate lead-attributable economic costs and limited our analysis to the neurodevelopmental impacts of lead, assessed as decrements in IQ points. Our main outcome was lost lifetime economic productivity due to early childhood exposure. We estimated a total cost of $977 billions of international dollars in low- and middle-income countries, with economic losses equal to $134.7 billion in Africa [4.03% of gross domestic product (GDP)], $142.3 billion in Latin America and the Caribbean (2.04% of GDP), and $699.9 billion in Asia (1.88% of GDP). Our sensitivity analysis indicates a total economic loss in the range of $728.6-1162.5 billion. We estimated that, in low- and middle-income countries, the burden associated with childhood lead exposure amounts to 1.20% of world GDP in 2011. For comparison, in the United States and Europe lead-attributable economic costs have been estimated at $50.9 and $55 billion, respectively, suggesting that the largest burden of lead exposure is now borne by low- and middle-income countries.

  6. Basic mechanism leading to stimulation of glycogenolysis by isoproterenol, EGF, elevated extracellular K+ concentrations, or GABA.

    PubMed

    Xu, Junnan; Song, Dan; Bai, Qiufang; Cai, Liping; Hertz, Leif; Peng, Liang

    2014-04-01

    Glycogenolysis, in brain parenchyma an astrocyte-specific process, has changed from being envisaged as an emergency procedure to playing central roles during brain response to whisker stimulation, memory formation, astrocytic K(+) uptake and stimulated release of ATP. It is activated by several transmitters and by even very small increases in extracellular K(+) concentration, and to be critically dependent upon an increase in free cytosolic Ca(2+) concentration ([Ca(2+)]i), whereas cAMP plays only a facilitatory role together with increased [Ca(2+)]i. Detailed knowledge about the signaling pathways eliciting glycogenolysis is therefore of interest and was investigated in the present study in well differentiated cultures of mouse astrocytes. The β-adrenergic agonist isoproterenol stimulated glycogenolysis by a β1-adrenergic effect, which initiated a pathway in which cAMP/protein kinase A activated a Gi/Gs shift, leading to Ca(2+)-activated glycogenolysis. Inhibition of this pathway downstream of cAMP but upstream of the Gi/Gs shift abolished the glycogenolysis. However, inhibitors operating downstream of the Ca(2+)-sensitive step, but preventing transactivation-mediated epidermal growth factor (EGF) receptor stimulation, a later step in the activated pathway, also caused inhibition of glycogenolysis. For this reason the effect of EGF was investigated and it was found to be glycogenolytic. Large increases in extracellular K(+) activated glycogenolysis by a nifedipine-inhibited L-channel opening allowing influx of Ca(2+), known to be glycogenolysis-dependent. Small increases (addition of 5 mM KCl) caused a smaller effect by a similarly glycogenolysis-reliant opening of an IP3 receptor-dependent ouabain signaling pathway. The same pathway could be activated by GABA (also in brain slices) due to its depolarizing effect in astrocytes.

  7. An ecological risk assessment of lead shot exposure in upland game birds and raptors

    SciTech Connect

    Kendall, R.I.; Lacher, T.E. Jr.; Bunck, C.

    1995-12-31

    There is concern about exposure of birds in terrestrial ecosystems to spent lead shot. Upland birds, particularly mourning doves, ingest spent lead shot; raptors ingest lead shot by consuming wounded game. Mortality, neurological dysfunction, immune suppression and reproductive impairment are effects of exposure to lead. The authors conducted an ecological risk assessment (using the new USEPA Ecological Risk Assessment Paradigm) on the impact of lead shot exposure in upland birds. Large amounts of lead shot are released into the environment each year from shooting and hunting. Doves collected from fields cultivated to attract mourning doves for hunting contain ingested spent lead shot. This might underestimate risk because doves ingesting shot may experience lead toxicosis and not be collected by hunters. Because lead can cause both acute and chronic toxicity if ingested and there is evidence of widespread liberation of lead shot in terrestrial ecosystems, concern for impacts on upland game birds and raptors is warranted. Although this ecological risk assessment does not clearly define a significant risk of upland game birds to lead shot, there is little evidence to rebut the presumption of risk. This issue merits continued scrutiny to protect upland game bird and raptor resources.

  8. Lead exposure in young school children in South African subsistence fishing communities.

    PubMed

    Mathee, Angela; Khan, Taskeen; Naicker, Nisha; Kootbodien, Tahira; Naidoo, Shan; Becker, Piet

    2013-10-01

    Lead is an established toxic substance, with wide-ranging health effects, including neurodevelopmental decrements and behavioural problems, even at low levels in blood. Anecdotal reports of lead melting to make fishing sinkers in South African subsistence fishing communities prompted the conduct of an epidemiological study in two South African fishing villages to investigate the extent of lead melting and the associated risks in children. The objectives of the study were to determine the extent of lead melting, and the blood lead distributions and associated risk factors in children. Cross-sectional, analytical studies were undertaken among 160 young school children in the fishing villages of Struis Bay and Elands Bay located along the south-eastern and western South African coastline, respectively. Blood samples were collected for lead content analysis, and anthropometric and hemoglobin measurements were taken. Questionnaires were administered to obtain information about socio-economic status and risk factors for lead exposure. Blood lead levels ranged from 2.2 to 22.4 µg/dl, with the mean blood lead level equalling 7.4. Around 74% of the children had blood lead levels ≥5 µg/dl and 16% had blood lead levels ≥10 µg/dl. Socio-economic factors, and lead melting practices were strongly associated with elevated blood lead levels. Blood lead levels in these remote subsistence fishing communities were unexpectedly elevated, given the absence of local lead industries or other obvious sources of lead exposure. Lead exposure and poisoning is an important, yet neglected, public health concern in South African subsistence fishing communities, and potentially on the entire African continent. Copyright © 2013 Elsevier Inc. All rights reserved.

  9. Children's Lead Exposure: A Multimedia Modeling Analysis to Guide Public Health Decision-Making.

    PubMed

    Zartarian, Valerie; Xue, Jianping; Tornero-Velez, Rogelio; Brown, James

    2017-09-12

    Drinking water and other sources for lead are the subject of public health concerns around the Flint, Michigan, drinking water and East Chicago, Indiana, lead in soil crises. In 2015, the U.S. Environmental Protection Agency (EPA)'s National Drinking Water Advisory Council (NDWAC) recommended establishment of a "health-based, household action level" for lead in drinking water based on children's exposure. The primary objective was to develop a coupled exposure-dose modeling approach that can be used to determine what drinking water lead concentrations keep children's blood lead levels (BLLs) below specified values, considering exposures from water, soil, dust, food, and air. Related objectives were to evaluate the coupled model estimates using real-world blood lead data, to quantify relative contributions by the various media, and to identify key model inputs. A modeling approach using the EPA's Stochastic Human Exposure and Dose Simulation (SHEDS)-Multimedia and Integrated Exposure Uptake and Biokinetic (IEUBK) models was developed using available data. This analysis for the U.S. population of young children probabilistically simulated multimedia exposures and estimated relative contributions of media to BLLs across all population percentiles for several age groups. Modeled BLLs compared well with nationally representative BLLs (0-23% relative error). Analyses revealed relative importance of soil and dust ingestion exposure pathways and associated Pb intake rates; water ingestion was also a main pathway, especially for infants. This methodology advances scientific understanding of the relationship between lead concentrations in drinking water and BLLs in children. It can guide national health-based benchmarks for lead and related community public health decisions. https://doi.org/10.1289/EHP1605.

  10. Sex-based differences in gene expression in hippocampus following postnatal lead exposure

    SciTech Connect

    Schneider, J.S. Anderson, D.W.; Sonnenahalli, H.; Vadigepalli, R.

    2011-10-15

    The influence of sex as an effect modifier of childhood lead poisoning has received little systematic attention. Considering the paucity of information available concerning the interactive effects of lead and sex on the brain, the current study examined the interactive effects of lead and sex on gene expression patterns in the hippocampus, a structure involved in learning and memory. Male or female rats were fed either 1500 ppm lead-containing chow or control chow for 30 days beginning at weaning.Blood lead levels were 26.7 {+-} 2.1 {mu}g/dl and 27.1 {+-} 1.7 {mu}g/dl for females and males, respectively. The expression of 175 unique genes was differentially regulated between control male and female rats. A total of 167 unique genes were differentially expressed in response to lead in either males or females. Lead exposure had a significant effect without a significant difference between male and female responses in 77 of these genes. In another set of 71 genes, there were significant differences in male vs. female response. A third set of 30 genes was differentially expressed in opposite directions in males vs. females, with the majority of genes expressed at a lower level in females than in males. Highly differentially expressed genes in males and females following lead exposure were associated with diverse biological pathways and functions. These results show that a brief exposure to lead produced significant changes in expression of a variety of genes in the hippocampus and that the response of the brain to a given lead exposure may vary depending on sex. - Highlights: > Postnatal lead exposure has a significant effect on hippocampal gene expression patterns. > At least one set of genes was affected in opposite directions in males and females. > Differentially expressed genes were associated with diverse biological pathways.

  11. Lead Levels in Landfill Areas and Childhood Exposure: An Integrative Review.

    PubMed

    Kim, M Angela; Williams, Kimberly A

    2017-01-01

    Landfills are high-risk areas for environmental lead exposure for children living in poverty stricken areas in many countries. This review examines landfills and lead toxicity in children. The review discusses the effects of lead toxicity, provides evidenced based recommendations to reduce lead exposure, and identify gaps in the evidence. A database search was conducted of articles in English from 1985 to 2014. Ten articles met the inclusion criteria. The Whittemore and Knafl framework and the John Hopkins Research Evidence Appraisal Tool(©) were used for reviewing the data. Elevated blood lead levels (BLLs) of children living near landfills were related to increased soil lead levels. Toxic effects of lead included adverse outcomes such as encephalopathy or death for children. Different approaches to decrease lead level include environmental surveillance, BLL screening, and soil abatement which are costly. Increased BLL through environmental exposure is connected with poor health outcomes and death among children. Evidence-based prevention included monitoring and screening and costly soil abatement. It is recommended that future studies focus on community education for exposure avoidance for children living near landfill areas. © 2016 Wiley Periodicals, Inc.

  12. Glazed clay pottery and lead exposure in Mexico: Current experimental evidence.

    PubMed

    Diaz-Ruiz, Araceli; Tristán-López, Luis Antonio; Medrano-Gómez, Karen Itzel; Torres-Domínguez, Juan Alejandro; Ríos, Camilo; Montes, Sergio

    2017-11-01

    Lead exposure remains a significant environmental problem; lead is neurotoxic, especially in developing humans. In Mexico, lead in human blood is still a concern. Historically, much of the lead exposure is attributed to the use of handcrafted clay pottery for cooking, storing and serving food. However, experimental cause-and-effect demonstration is lacking. The present study explores this issue with a prospective experimental approach. We used handcrafted clay containers to prepare and store lemonade, which was supplied as drinking water to pregnant rats throughout the gestational period. We found that clay pots, jars, and mugs leached on average 200 µg/l lead, and exposure to the lemonade resulted in 2.5 µg/dl of lead in the pregnant rats' blood. Neonates also showed increased lead content in the hippocampus and cerebellum. Caspase-3 activity was found to be statistically increased in the hippocampus in prenatally exposed neonates, suggesting increased apoptosis in that brain region. Glazed ceramics are still an important source of lead exposure in Mexico, and our results confirm that pregnancy is a vulnerable period for brain development.

  13. Lead exposure suppressed ALAD transcription by increasing methylation level of the promoter CpG islands.

    PubMed

    Li, Chunping; Xu, Ming; Wang, Sumeng; Yang, Xiaolin; Zhou, Shourong; Zhang, Jingping; Liu, Qizhan; Sun, Yujie

    2011-05-30

    DNA methylation provides a plausible link between the environment and alterations in gene expression that may lead to disease phenotypes. Lead exposure can change DNA methylation status. Here, we hypothesized that the methylation of the ALAD gene promoter may play an important role in lead toxicity. To determine whether the methylation level of the ALAD promoter is associated with the risk of lead poisoning, we conducted a case-control study of 103 workers from a battery plant and 103 healthy volunteers with matching age and gender distribution. We employed real-time PCR and methylation-specific PCR (MSP) in cell models to determine the relationship between ALAD methylation level and transcription level. We found lead exposure to increase the ALAD gene methylation level and down-regulate ALAD transcription. The difference in methylation frequencies between exposures and controls was statistically significant (p=0.002), and individuals with methylated ALAD gene showed an increased risk of lead poisoning (adjusted OR=3.57, 95% CI, 1.55-8.18). This study suggests that the lead-exposure-induced increases in ALAD methylation may be involved in the mechanism of lead toxicity. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  14. Early chronic lead exposure reduces exploratory activity in young C57BL/6J mice.

    PubMed

    Flores-Montoya, Mayra Gisel; Sobin, Christina

    2015-07-01

    Research has suggested that chronic low-level lead exposure diminishes neurocognitive function in children. Tests that are sensitive to behavioral effects at lowest levels of lead exposure are needed for the development of animal models. In this study we investigated the effects of chronic low-level lead exposure on exploratory activity (unbaited nose poke task), exploratory ambulation (open field task) and motor coordination (Rotarod task) in pre-adolescent mice. C57BL/6J pups were exposed to 0 ppm (controls), 30 ppm (low-dose) or 230 ppm (high-dose) lead acetate via dams' drinking water administered from birth to postnatal day 28, to achieve a range of blood lead levels (BLLs) from not detectable to 14.84 µg dl(-1) ). At postnatal day 28, mice completed behavioral testing and were killed (n = 61). BLLs were determined by inductively coupled plasma mass spectrometry. The effects of lead exposure on behavior were tested using generalized linear mixed model analyses with BLL, sex and the interaction as fixed effects, and litter as the random effect. BLL predicted decreased exploratory activity and no threshold of effect was apparent. As BLL increased, nose pokes decreased. The C57BL/6J mouse is a useful model for examining effects of early chronic low-level lead exposure on behavior. In the C57BL/6J mouse, the unbaited nose poke task is sensitive to the effects of early chronic low-level lead exposure. This is the first animal study to show behavioral effects in pre-adolescent lead-exposed mice with BLL below 5 µg dl(-1).

  15. Recent Developments in Low-Level Lead Exposure and Intellectual Impairment in Children

    PubMed Central

    Koller, Karin; Brown, Terry; Spurgeon, Anne; Levy, Len

    2004-01-01

    In the last decade children’s blood lead levels have fallen significantly in a number of countries, and current mean levels in developed countries are in the region of 3 μg/dL. Despite this reduction, childhood lead poisoning continues to be a major public health problem for certain at-risk groups of children, and concerns remain over the effects of lead on intellectual development in infants and children. The evidence for lowered cognitive ability in children exposed to lead has come largely from prospective epidemiologic studies. The current World Health Organization/Centers for Disease Control and Prevention blood level of concern reflects this and stands at 10 μg/dL. However, a recent study on a cohort of children whose lifetime peak blood levels were consistently < 10 μg/dL has extended the association of blood lead and intellectual impairment to lower levels of lead exposure and suggests there is no safety margin at existing exposures. Because of the importance of this finding, we reviewed this study in detail along with other recent developments in the field of low-level lead exposure and children’s cognitive development. We conclude that these findings are important scientifically, and efforts should continue to reduce childhood exposure. However, from a public health perspective, exposure to lead should be seen within the many other risk factors impacting on normal childhood development, in particular the influence of the learning environment itself. Current lead exposure accounts for a very small amount of variance in cognitive ability (1–4%), whereas social and parenting factors account for 40% or more. PMID:15198918

  16. Locomotor damage and brain oxidative stress induced by lead exposure are attenuated by gallic acid treatment.

    PubMed

    Reckziegel, Patrícia; Dias, Verônica Tironi; Benvegnú, Dalila; Boufleur, Nardeli; Silva Barcelos, Raquel Cristine; Segat, Hecson Jesser; Pase, Camila Simonetti; Dos Santos, Clarissa Marques Moreira; Flores, Erico Marlon Moraes; Bürger, Marilise Escobar

    2011-05-30

    We investigated the antioxidant potential of gallic acid (GA), a natural compound found in vegetal sources, on the motor and oxidative damages induced by lead. Rats exposed to lead (50 mg/kg, i.p., once a day, 5 days) were treated with GA (13.5mg/kg, p.o.) or EDTA (110 mg/kg, i.p.) daily, for 3 days. Lead exposure decreased the locomotor and exploratory activities, reduced blood ALA-D activity, and increased brain catalase (CAT) activity without altering other antioxidant defenses. Brain oxidative stress (OS) estimated by lipid peroxidation (TBARS) and protein carbonyl were increased by lead. GA reversed the motor behavior parameters, the ALA-D activity, as well as the markers of OS changed by lead exposure. CAT activity remained high, possibly as a compensatory mechanism to eliminate hydroperoxides during lead poisoning. EDTA, a conventional chelating agent, was not beneficial on the lead-induced motor behavior and oxidative damages. Both GA (less) and EDTA (more) reduced the lead accumulation in brain tissue. Negative correlations were observed between the behavioral parameters and lipid peroxidation and the lead levels in brain tissue. In conclusion, GA may be an adjuvant in lead exposure, mainly by its antioxidant properties against the motor and oxidative damages resulting from such poisoning. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  17. Lead exposure affects health indices in free-ranging ducks in Argentina.

    PubMed

    Ferreyra, Hebe; Beldomenico, Pablo M; Marchese, Krysten; Romano, Marcelo; Caselli, Andrea; Correa, Ana I; Uhart, Marcela

    2015-05-01

    Numerous experiments under controlled conditions and extensive investigation of waterfowl die-offs have demonstrated that exposure to lead from spent gunshot is highly detrimental to the health of waterfowl. However, few studies have focused on examining the more subtle sub-lethal effects of lead toxicity on ducks in non-experimental settings. In our study, the health of ducks exposed to varying amounts of lead under natural conditions was assessed by correlating individual lead exposure with relevant indices of health. Based on hunter-killed wild ducks in Argentina, we measured spleen mass, body condition, examined bone marrow smears, and determined Ca and P in bone tissue. In free-ranging live-trapped ducks we determined basic hematology and aminolevulinic acid dehydratase activity. Using multivariate analyses, we found that, when controlling for the potential confounding effect of site type, year, duck species, body mass and age, lead levels in the liver were negatively associated with body condition and spleen mass. Spleen mass was also lower in ducks with higher lead levels in their bones. In live ducks, high blood lead levels were associated with low packed cell volume and red cell morphologic abnormalities. These findings suggest that, despite the lack of recorded lead-induced mortality in the region, lead exposure results in less conspicuous but still significant impacts on the health of ducks, which could have serious implications for their conservation. Moreover, this evidence further supports the need for urgently banning lead shot in the region.

  18. Electrode alignment of transverse tripoles using a percutaneous triple-lead approach in spinal cord stimulation

    NASA Astrophysics Data System (ADS)

    Sankarasubramanian, V.; Buitenweg, J. R.; Holsheimer, J.; Veltink, P.

    2011-02-01

    The aim of this modeling study is to determine the influence of electrode alignment of transverse tripoles on the paresthesia coverage of the pain area in spinal cord stimulation, using a percutaneous triple-lead approach. Transverse tripoles, comprising a central cathode and two lateral anodes, were modeled on the low-thoracic vertebral region (T10-T12) using percutaneous triple-lead configurations, with the center lead on the spinal cord midline. The triple leads were oriented both aligned and staggered. In the staggered configuration, the anodes were offset either caudally (caudally staggered) or rostrally (rostrally staggered) with respect to the midline cathode. The transverse tripolar field steering with the aligned and staggered configurations enabled the estimation of dorsal column fiber thresholds (IDC) and dorsal root fiber thresholds (IDR) at various anodal current ratios. IDC and IDR were considerably higher for the aligned transverse tripoles as compared to the staggered transverse tripoles. The aligned transverse tripoles facilitated deeper penetration into the medial dorsal columns (DCs). The staggered transverse tripoles always enabled broad and bilateral DC activation, at the expense of mediolateral steerability. The largest DC recruited area was obtained with the rostrally staggered transverse tripole. Transverse tripolar geometries, using percutaneous leads, allow for selective targeting of either medial or lateral DC fibers, if and only if the transverse tripole is aligned. Steering of anodal currents between the lateral leads of the staggered transverse tripoles cannot target medially confined populations of DC fibers in the spinal cord. An aligned transverse tripolar configuration is strongly recommended, because of its ability to provide more post-operative flexibility than other configurations.

  19. Chronic cadmium exposure stimulates SDF-1 expression in an ERα dependent manner.

    PubMed

    Ponce, Esmeralda; Aquino, Natalie B; Louie, Maggie C

    2013-01-01

    Cadmium is an omnipotent environmental contaminant associated with the development of breast cancer. Studies suggest that cadmium functions as an endocrine disruptor, mimicking the actions of estrogen in breast cancer cells and activating the receptor to promote cell growth. Although acute cadmium exposure is known to promote estrogen receptor-mediated gene expression associated with growth, the consequence of chronic cadmium exposure is unclear. Since heavy metals are known to bioaccumulate, it is necessary to understand the effects of prolonged cadmium exposure. This study aims to investigate the effects of chronic cadmium exposure on breast cancer progression. A MCF7 breast cancer cell line chronically exposed to 10(-7) M CdCl2 serves as our model system. Data suggest that prolonged cadmium exposures result in the development of more aggressive cancer phenotypes - increased cell growth, migration and invasion. The results from this study show for the first time that chronic cadmium exposure stimulates the expression of SDF-1 by altering the molecular interactions between ERα, c-jun and c-fos. This study provides a mechanistic link between chronic cadmium exposure and ERα and demonstrates that prolonged, low-level cadmium exposure contributes to breast cancer progression.

  20. Chronic Cadmium Exposure Stimulates SDF-1 Expression in an ERα Dependent Manner

    PubMed Central

    Ponce, Esmeralda; Aquino, Natalie B.; Louie, Maggie C.

    2013-01-01

    Cadmium is an omnipotent environmental contaminant associated with the development of breast cancer. Studies suggest that cadmium functions as an endocrine disruptor, mimicking the actions of estrogen in breast cancer cells and activating the receptor to promote cell growth. Although acute cadmium exposure is known to promote estrogen receptor-mediated gene expression associated with growth, the consequence of chronic cadmium exposure is unclear. Since heavy metals are known to bioaccumulate, it is necessary to understand the effects of prolonged cadmium exposure. This study aims to investigate the effects of chronic cadmium exposure on breast cancer progression. A MCF7 breast cancer cell line chronically exposed to 10−7 M CdCl2 serves as our model system. Data suggest that prolonged cadmium exposures result in the development of more aggressive cancer phenotypes – increased cell growth, migration and invasion. The results from this study show for the first time that chronic cadmium exposure stimulates the expression of SDF-1 by altering the molecular interactions between ERα, c-jun and c-fos. This study provides a mechanistic link between chronic cadmium exposure and ERα and demonstrates that prolonged, low-level cadmium exposure contributes to breast cancer progression. PMID:24015267

  1. Lead Exposure in Different Organs of Mammals and Prevention by Curcumin-Nanocurcumin: a Review.

    PubMed

    Pal, Mili; Sachdeva, Meenu; Gupta, Niharika; Mishra, Priyanka; Yadav, Mahavir; Tiwari, Archana

    2015-12-01

    Chronic lead exposure is related to many health diseases in mammals. Exposure to lead forms reactive oxygen species reducing body antioxidant enzymes inflicting injury to numerous macromolecules or cell necrosis. Recent studies have revealed oxidative stress as the vital mechanism for lead toxicity. Lead is found to be toxic to several organ systems such as hematopoietic, skeletal, renal, cardiac, hepatic, and reproductive systems and extremely toxic to the central nervous system (CNS). Curcumin, an active ingredient of the dietary spice, and nanocurcumin, a nanoform of curcumin, are found to decrease toxicity due to lead in various organ systems in mouse models. Higher bioavailability, chelating property, and retention time of nanocurcumin over bulk curcumin may pave the way to expand the utility of nanocurcumin to remove lead toxicity from various organ systems within humans.

  2. Early lead exposure (<3 years old) prospectively predicts fourth grade school suspension in Milwaukee, Wisconsin (USA).

    PubMed

    Amato, Michael S; Magzamen, Sheryl; Imm, Pamela; Havlena, Jeffrey A; Anderson, Henry A; Kanarek, Marty S; Moore, Colleen F

    2013-10-01

    School suspensions are associated with negative student outcomes. Environmental lead exposure increases hyperactivity and sensory defensiveness, two traits likely to increase classroom misbehavior and subsequent discipline. Childhood Blood Lead Level (BLL) test results categorized urban fourth graders as exposed (2687; lifetime max BLL 10-20 µg/dL) or unexposed (1076; no lifetime BLL ≥5 µg/dL). Exposed children were over twice as likely as unexposed children to be suspended (OR=2.66, 95% CI=[2.12, 3.32]), controlling for covariates. African American children were more likely to be suspended than white children, but lead exposure explained 23% of the racial discipline gap. These results suggest that different rates of environmental lead exposure may contribute to the racial discipline gap. Copyright © 2013 Elsevier Inc. All rights reserved.

  3. Lead stimulates ERK1/2 and p38MAPK phosphorylation in the hippocampus of immature rats.

    PubMed

    Cordova, Fabiano M; Rodrigues, Ana Lúcia S; Giacomelli, Maria B O; Oliveira, Camila S; Posser, Thaís; Dunkley, Peter R; Leal, Rodrigo B

    2004-02-13

    Lead (Pb(2+)) is widely recognized as a neurotoxicant whose mechanisms of action are not completely established. We have previously demonstrated that Pb(2+) can activate the p38(MAPK) pathway and increase the phosphorylation of Hsp27 in bovine adrenal chromaffin cells and human SH SY5Y cells over a short incubation period (1 h). In the present work we analyzed the effects of Pb(2+) administered in vivo on the level and the phosphorylation state of ERK1/2 and p38(MAPK) in the hippocampus of immature rats. Rats were treated with lead acetate (2, 8 or 12 mg/kg, i.p.) or saline (control) over the 8th to 12th postnatal days, and hippocampal slices were prepared on the 14th day. The Pb(2+) level in the lead-treated animals increased 2.5-6-fold in the blood (3.0-6.0 microg/dl) and 2.0-3.0-fold in the forebrain (78-103 ng/g wet weight), compared to control (saline). The phosphorylation of both ERK1/2 and p38(MAPK) was significantly increased by prior exposure to Pb(2+) in vivo. In in vitro experiments, hippocampal slices from 14-day-old rats were exposed to Pb(2+) (1-10 microM) for 1 and 3 h. There were no changes in the phosphorylation state of ERK and p38(MAPK) for 1-h incubation, whereas a significant increase of ERK1/2 and p38(MAPK) phosphorylation by Pb(2+) (5 microM) was observed for the 3-h incubation. Cell viability measured using MTT was not modified in any of the conditions tested. These results indicate that the phosphorylation of hippocampal ERK1/2 and p38(MAPK) is stimulated by lead in a period of rapid brain development, an effect that may underlie, at least in part, the neurotoxicty elicited by this metal.

  4. Effect of Lead Exposure on the Status of Reticulocyte Count Indices among Workers from Lead Battery Manufacturing Plant.

    PubMed

    Kalahasthi, Ravibabu; Barman, Tapu

    2016-10-01

    Earlier studies conducted on lead-exposed workers have determined the reticulocyte count (RC) (%), but the parameters of Absolute Reticulocyte Count (ARC), Reticulocyte Index (RI), and Reticulocyte Production Index (RPI) were not reported. This study assessed the effect of lead (Pb) exposure on the status of reticulocyte count indices in workers occupied in lead battery plants. The present cross-sectional study was carried out on 391 male lead battery workers. The blood lead levels (BLL) were determined by using an Atomic Absorption Spectrophotometer. The RC (%) was estimated by using the supravital staining method. The parameters, such as ARC, RI, and RPI, were calculated by using the RC (%) with the red cell indices (RBC count and hematocrit). The levels of RBC count and hematocrit were determined by using an ABX Micros ES-60 hematology analyzer. The levels of reticulocyte count indices - RC (%), ARC, RI, and RPI significantly increased with elevated BLL. The association between BLL and reticulocyte count indices was positive and significant. The results of linear multiple regression analysis showed that the reticulocyte count (β = 0.212, P < 0.001), ARC (β = 0.217, P < 0.001), RI (β = 0.194, P < 0.001), and RPI (β = 0.208, P < 0.001) were positively associated with BLL. The variable, smoking habits, showed a significant positive association with reticulocyte count indices: RC (%) (β = 0.188, P < 0.001), ARC (β = 0.174, P < 0.001), RI (β = 0.200, P < 0.001), and RPI (β = 0.151, P < 0.005). The study results revealed that lead exposure may cause reticulocytosis with an increase of reticulocyte count indices.

  5. Effect of Lead Exposure on the Status of Reticulocyte Count Indices among Workers from Lead Battery Manufacturing Plant

    PubMed Central

    Kalahasthi, Ravibabu; Barman, Tapu

    2016-01-01

    Earlier studies conducted on lead-exposed workers have determined the reticulocyte count (RC) (%), but the parameters of Absolute Reticulocyte Count (ARC), Reticulocyte Index (RI), and Reticulocyte Production Index (RPI) were not reported. This study assessed the effect of lead (Pb) exposure on the status of reticulocyte count indices in workers occupied in lead battery plants. The present cross-sectional study was carried out on 391 male lead battery workers. The blood lead levels (BLL) were determined by using an Atomic Absorption Spectrophotometer. The RC (%) was estimated by using the supravital staining method. The parameters, such as ARC, RI, and RPI, were calculated by using the RC (%) with the red cell indices (RBC count and hematocrit). The levels of RBC count and hematocrit were determined by using an ABX Micros ES-60 hematology analyzer. The levels of reticulocyte count indices - RC (%), ARC, RI, and RPI significantly increased with elevated BLL. The association between BLL and reticulocyte count indices was positive and significant. The results of linear multiple regression analysis showed that the reticulocyte count (β = 0.212, P < 0.001), ARC (β = 0.217, P < 0.001), RI (β = 0.194, P < 0.001), and RPI (β = 0.208, P < 0.001) were positively associated with BLL. The variable, smoking habits, showed a significant positive association with reticulocyte count indices: RC (%) (β = 0.188, P < 0.001), ARC (β = 0.174, P < 0.001), RI (β = 0.200, P < 0.001), and RPI (β = 0.151, P < 0.005). The study results revealed that lead exposure may cause reticulocytosis with an increase of reticulocyte count indices. PMID:27818730

  6. Personal exposure, behavior, and work site conditions as determinants of blood lead among bridge painters.

    PubMed

    Rodrigues, Ema G; Virji, M Abbas; McClean, Michael D; Weinberg, Janice; Woskie, Susan; Pepper, Lewis D

    2010-02-01

    Bridge painters are exposed to lead during several job tasks performed during the workday, such as sanding, scraping, and blasting. After the Occupational Safety and Health Administration standard was passed in 1993 to control lead exposures among construction workers including bridge painters, this study was conducted among 84 bridge painters in the New England area to determine the significant predictors of blood lead levels. Lead was measured in personal air and hand wipe samples that were collected during the 2-week study period and in blood samples that were collected at the beginning and at the end of the study period. The personal air and hand wipe data as well as personal behaviors (i.e., smoking, washing, wearing a respirator) and work site conditions were analyzed as potential determinants of blood lead levels using linear mixed effects models. Our results show that the mean air lead levels over the 2-week period were the most predictive exposure measure of blood lead levels. Other individual-level significant predictors of blood lead levels included months worked on bridge painting crews, education, and personal hygiene index. Of the site-level variables investigated, having a containment facility on site was a significant predictor of blood lead levels. Our results also indicate that hand wipe lead levels were significantly associated with higher blood lead levels at the end of the study period compared with the beginning of the study period. Similarly, smoking on site and respirator fit testing were significantly associated with higher blood lead levels at the end of the study period. This study shows that several individual-level and site-level factors are associated with blood lead levels among bridge painters, including lead exposure through inhalation and possible hand-to-mouth contact, personal behaviors such as smoking on site, respirator fit testing, and work site conditions such as the use of better containment facilities. Accordingly

  7. The association of lead exposure during pregnancy and childhood anthropometry in the Mexican PROGRESS cohort.

    PubMed

    Renzetti, Stefano; Just, Allan C; Burris, Heather H; Oken, Emily; Amarasiriwardena, Chitra; Svensson, Katherine; Mercado-García, Adriana; Cantoral, Alejandra; Schnaas, Lourdes; Baccarelli, Andrea A; Wright, Robert O; Téllez-Rojo, Martha María

    2017-01-01

    Lead exposure during pregnancy remains a public health problem with potential lifelong impacts on children's growth and development. Mexico is unique in that stunting and obesity are both major public health concerns in children. This situation might be exacerbated by lead exposure which remains more common in Mexico than in the United States due in part to the use of lead glazed pottery in food preparation and storage. Our objective is to determine how lead exposure during pregnancy is associated with children's growth parameters, including height, weight, body mass index and percentage body fat measured between ages 4-6 years old in a Mexico City pregnancy cohort. Blood lead was collected in the 2nd and 3rd trimester of pregnancy as well as at delivery. Bone lead was assessed in mothers as a long term exposure biomarker. We performed multivariable linear regression analyses to assess the association between each of these lead exposure biomarkers and child anthropometry. We found a significant negative association between maternal 3rd trimester blood lead concentration and offspring height for age (β-0.10; 95% CI -0.19, -0.01), and a negative association between maternal 3rd trimester blood lead concentration and weight for age (β-0.11; 95% CI -0.22,-0.003). Our results in this Mexican population add to previous findings of an association of lead and decreased stature and weight in early childhood. Ongoing follow-up and longitudinal analyses may help elucidate how this impacts growth trajectory and other children's health outcomes. Copyright © 2016 Elsevier Inc. All rights reserved.

  8. Effect of occupational exposure to lead on new risk factors for cardiovascular diseases.

    PubMed

    Prokopowicz, Adam; Sobczak, Andrzej; Szuła-Chraplewska, Magdalena; Zaciera, Marzena; Kurek, Jolanta; Szołtysek-Bołdys, Izabela

    2017-05-01

    The cardiovascular effects of lead are caused primarily through an effect on blood pressure but are not just limited to an increased risk of hypertension. The aim of our study was to determine to what extent chronic exposure to lead affects new risk factors for cardiovascular disease (CVD) development, such as biomarkers of inflammation (C reactive protein (CRP) and fibrinogen) and biomarkers of endothelial dysfunction (homocysteine, asymmetric dimethylarginine (ADMA) and L-homoarginine). A cross-sectional study was performed on a sample of 231 male volunteers, aged 20-60 years, working for at least 2 years in jobs with exposure to lead during the mining and processing of lead-zinc ores. The association between lead in blood and CVD biomarkers was evaluated using multiple linear regression, and the effects of exposure level were observed in workers divided into subgroups according to their blood lead concentration: <250, 250-400 and >400 µg/L. Lead in the blood correlated with new risk factors for CVD except for ADMA. Multiple regression analysis revealed that predictive properties for lead in the blood increased for particular biomarkers in the following order: L-homoarginine, fibrinogen, CRP and homocysteine. Among the specified groups, significant differences were observed only between the groups with the most and least exposure to lead, which differed in concentrations by 54.3% for CRP, 19.3% for fibrinogen, 10.6% for homocysteine and -25.5% for L-homoarginine. These findings support the hypothesis that occupational exposure to lead can promote atherosclerosis, particularly in highly exposed individuals. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  9. Altered myelination and axonal integrity in adults with childhood lead exposure: a diffusion tensor imaging study.

    PubMed

    Brubaker, Christopher J; Schmithorst, Vincent J; Haynes, Erin N; Dietrich, Kim N; Egelhoff, John C; Lindquist, Diana M; Lanphear, Bruce P; Cecil, Kim M

    2009-11-01

    Childhood lead exposure is associated with adverse cognitive, neurobehavioral and motor outcomes, suggesting altered brain structure and function. The purpose of this work was to assess the long-term impact of childhood lead exposure on white matter integrity in young adults. We hypothesized that childhood lead exposure would alter adult white matter architecture via deficits in axonal integrity and myelin organization. Adults (22.9+/-1.5 years, range 20.0-26.1 years) from the Cincinnati Lead Study were recruited to undergo a study employing diffusion tensor imaging (DTI). The anatomic regions of association between water diffusion characteristics in white matter and mean childhood blood lead level were determined for 91 participants (52 female). Fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD) were measured on an exploratory voxel-wise basis. In adjusted analyses, mean childhood blood lead levels were associated with decreased FA throughout white matter. Regions of the corona radiata demonstrated highly significant lead-associated decreases in FA and AD and increases in MD and RD. The genu, body, and splenium of the corpus callosum demonstrated highly significant lead-associated decreases in RD, smaller and less significant decreases in MD, and small areas with increases in AD. The results of this analysis suggest multiple insults appear as distinct patterns of white matter diffusion abnormalities in the adult brain. Neurotoxic insults from the significant lead burden the participants experienced throughout childhood affect neural elements differently and may be related to the developmental stage of myelination at periods of exposure. This study indicates that childhood lead exposure is associated with a significant and persistent impact on white matter microstructure as quantified with diffusivity changes suggestive of altered myelination and axonal integrity.

  10. Acute Lead Exposure Increases Arterial Pressure: Role of the Renin-Angiotensin System

    PubMed Central

    Simões, Maylla Ronacher; Ribeiro Júnior, Rogério F.; Vescovi, Marcos Vinícius A.; de Jesus, Honério C.; Padilha, Alessandra S.; Stefanon, Ivanita; Vassallo, Dalton V.; Salaices, Mercedes; Fioresi, Mirian

    2011-01-01

    Background Chronic lead exposure causes hypertension and cardiovascular disease. Our purpose was to evaluate the effects of acute exposure to lead on arterial pressure and elucidate the early mechanisms involved in the development of lead-induced hypertension. Methodology/Principal Findings Wistar rats were treated with lead acetate (i.v. bolus dose of 320 µg/Kg), and systolic arterial pressure, diastolic arterial pressure and heart rate were measured during 120 min. An increase in arterial pressure was found, and potential roles of the renin-angiotensin system, Na+,K+-ATPase and the autonomic reflexes in this change in the increase of arterial pressure found were evaluated. In anesthetized rats, lead exposure: 1) produced blood lead levels of 37±1.7 µg/dL, which is below the reference blood concentration (60 µg/dL); 2) increased systolic arterial pressure (Ct: 109±3 mmHg vs Pb: 120±4 mmHg); 3) increased ACE activity (27% compared to Ct) and Na+,K+-ATPase activity (125% compared to Ct); and 4) did not change the protein expression of the α1-subunit of Na+,K+-ATPase, AT1 and AT2. Pre-treatment with an AT1 receptor blocker (losartan, 10 mg/Kg) or an ACE inhibitor (enalapril, 5 mg/Kg) blocked the lead-induced increase of arterial pressure. However, a ganglionic blockade (hexamethonium, 20 mg/Kg) did not prevent lead's hypertensive effect. Conclusion Acute exposure to lead below the reference blood concentration increases systolic arterial pressure by increasing angiotensin II levels due to ACE activation. These findings offer further evidence that acute exposure to lead can trigger early mechanisms of hypertension development and might be an environmental risk factor for cardiovascular disease. PMID:21494558

  11. Prenatal Tobacco, Marijuana, Stimulant, and Opiate Exposure: Outcomes and Practice Implications

    PubMed Central

    Minnes, Sonia; Lang, Adelaide; Singer, Lynn

    2011-01-01

    Abuse of drugs by pregnant women both in the United States and worldwide has raised many questions regarding the effects of prenatal drug exposure on the developing fetus and subsequent child outcomes. Studies using the neurobehavioral teratology model have been undertaken to determine specific prenatal drug effects on cognitive and behavioral development. Here we summarize the findings of studies that have investigated the developmental effects of prenatal exposure to tobacco, marijuana, stimulants, and opiates. These studies consider the timing and amount of prenatal exposure; other drug exposures; maternal characteristics; and other health, nutritional, and environmental factors. We review treatment options for pregnant, substance-dependent women and therapeutic interventions for exposed children. PMID:22003423

  12. Lead exposure in passerines inhabiting lead-contaminated floodplains in the Coeur d'Alene River Basin, Idaho, USA

    SciTech Connect

    Johnson, G.D.; Kern, J.W.; Strickland, M.D.; McDonald, L.L. ); Audet, D.J.; LeCaptain, L.J. ); Hoffman, D.J. )

    1999-06-01

    Blood collected from song sparrows (Melospiza melodia) and American robins (Turdus migratorius) captured with mist nets in a lead-contaminated (assessment) area and nearby uncontaminated (reference) areas within the Coeur d'Alene Basin in northern Idaho was analyzed for [delta]-aminolevulinic acid dehydratase activity (ALAD) and hematocrit levels, and livers were analyzed for lead. Mean ALAD inhibition in the assessment area was 51% in song sparrows and 75% in American robins. The proportion of the sampled population with ALAD inhibition > 50% was calculated to be 43% for song sparrows and 83% for American robins. Assessment area hematocrit values for song sparrows and American robins were lower than in reference areas; however, differences were not statistically significant. Significantly higher levels of lead (wet weight) were found in livers from song sparrows captured on the assessment area ([bar x] = 1.93 ppm) than on reference areas. Study results indicate that 43% of the song sparrows and 83% of the American robins inhabiting the floodplain along the Coeur d'Alene River in the assessment area are being exposed to lead at levels sufficient to inhibit ALAD by > 50%. Variability in lead exposure indicators was attributed to high variability in environmental lead concentrations in the Coeur d'Alene River Basin.

  13. [Effects of lead exposure on 18 elements in blood and excretions in rats].

    PubMed

    Liu, Duo-jian; Wu, Jing; Liu, Ya-qiong; Ouyang, Li; Wang, Jing-yu

    2014-04-18

    To investigate the effects of lead exposure on lead and other metal elements contents in rats. SD rats were randomly divided into control group and several experiment groups of different doses. The rats were exposed to lead acetate through intragastric administration every other day for 5 times. The whole blood, urine and feces of all the rats were collected. The concentrations of lead and 18 metal elements in these samples were determined by inductively coupled plasma mass spectrometry (ICP-MS) and inductively coupled plasma atom emission spectrometry (ICP-AES). No significant difference among the groups was found for body weight and organ-body ratios of the rats after lead exposure (P>0.05). With the increase of exposure dose, lead content in blood, total lead in urine and feces tended to increase, while the total lead in urine no longer increased in the high dose group. Significant differences among the groups (P<0.05) were observed for the sodium, magnesium, potassium, strontium, antimony, thallium and bismuth contents in the whole blood, the potassium, iron and antimony contents in the urine, and the calcium, iron, zinc, copper, thallium, bismuth and rare earth elements contents in the feces. The effect of lead on the metabolism of divalent metal ions, namely calcium, magnesium, iron, zinc, copper and strontium ion, may be due to the competition of lead with the ions for common delivery carrier. Lead exposure induces the excretion of light rare earth elements and toxic elements (thallium and bismuth), and changes the antimony, sodium and potassium contents in rats. But there is no effect of lead on molybdenum and cadmium in rats.

  14. Lead Exposure in Bald Eagles from Big Game Hunting, the Continental Implications and Successful Mitigation Efforts

    PubMed Central

    Bedrosian, Bryan; Craighead, Derek; Crandall, Ross

    2012-01-01

    Studies suggest hunter discarded viscera of big game animals (i.e., offal) is a source of lead available to scavengers. We investigated the incidence of lead exposure in bald eagles in Wyoming during the big game hunting season, the influx of eagles into our study area during the hunt, the geographic origins of eagles exposed to lead, and the efficacy of using non-lead rifle ammunition to reduce lead in eagles. We tested 81 blood samples from bald eagles before, during and after the big game hunting seasons in 2005–2010, excluding 2008, and found eagles had significantly higher lead levels during the hunt. We found 24% of eagles tested had levels indicating at least clinical exposure (>60 ug/dL) during the hunt while no birds did during the non-hunting seasons. We performed driving surveys from 2009–2010 to measure eagle abundance and found evidence to suggest that eagles are attracted to the study area during the hunt. We fitted 10 eagles with satellite transmitters captured during the hunt and all migrated south after the cessation of the hunt. One returned to our study area while the remaining nine traveled north to summer/breed in Canada. The following fall, 80% returned to our study area for the hunting season, indicating that offal provides a seasonal attractant for eagles. We fitted three local breeding eagles with satellite transmitters and none left their breeding territories to feed on offal during the hunt, indicating that lead ingestion may be affecting migrants to a greater degree. During the 2009 and 2010 hunting seasons we provided non-lead rifle ammunition to local hunters and recorded that 24% and 31% of successful hunters used non-lead ammunition, respectively. We found the use of non-lead ammunition significantly reduced lead exposure in eagles, suggesting this is a viable solution to reduce lead exposure in eagles. PMID:23284837

  15. The relationship between blood lead levels and occupational exposure in a pregnant population.

    PubMed

    La-Llave-León, Osmel; Salas Pacheco, José Manuel; Estrada Martínez, Sergio; Esquivel Rodríguez, Eloísa; Castellanos Juárez, Francisco X; Sandoval Carrillo, Ada; Lechuga Quiñones, Angélica María; Vázquez Alanís, Fernando; García Vargas, Gonzalo; Méndez Hernández, Edna Madai; Duarte Sustaita, Jaime

    2016-12-07

    Pregnant women exposed to lead are at risk of suffering reproductive damages, such as miscarriage, preeclampsia, premature delivery and low birth weight. Despite that the workplace offers the greatest potential for lead exposure, there is relatively little information about occupational exposure to lead during pregnancy. This study aims to assess the association between blood lead levels and occupational exposure in pregnant women from Durango, Mexico. A cross-sectional study was carried out in a population of 299 pregnant women. Blood lead was measured in 31 women who worked in jobs where lead is used (exposed group) and 268 who did not work in those places (control group). Chi-square test was applied to compare exposed and control groups with regard to blood lead levels. Odds ratio (OR) and 95% confidence intervals (CI) were calculated. Multivariable regression analysis was applied to determine significant predictors of blood lead concentrations in the exposed group. Exposed women had higher blood lead levels than those in the control group (4.00 ± 4.08 μg/dL vs 2.65 ± 1.75 μg/dL, p = 0.002). Furthermore, women in the exposed group had 3.82 times higher probability of having blood lead levels ≥ 5 μg/dL than those in the control group. Wearing of special workwear, changing clothes after work, living near a painting store, printing office, junkyard or rubbish dump, and washing the workwear together with other clothes resulted as significant predictors of elevated blood lead levels in the exposed group. Pregnant working women may be at risk of lead poisoning because of occupational and environmental exposure. The risk increases if they do not improve the use of protective equipment and their personal hygiene.

  16. Reducing lead exposure from drinking water: recent history and current status.

    PubMed Central

    Maas, Richard P.; Patch, Steven C.; Morgan, Diane M.; Pandolfo, Tamara J.

    2005-01-01

    This article discusses the issue of lead contamination of drinking water, noting the various regulatory-driven measures that have been adopted in the U.S. since 1986 to address this public health issue. The article summarizes the literature on the dynamics of tap water lead contamination and discusses this widespread source of lead exposure in the context of the latest research evidence. PMID:16134575

  17. Lead exposure in bald eagles from big game hunting, the continental implications and successful mitigation efforts.

    PubMed

    Bedrosian, Bryan; Craighead, Derek; Crandall, Ross

    2012-01-01

    Studies suggest hunter discarded viscera of big game animals (i.e., offal) is a source of lead available to scavengers. We investigated the incidence of lead exposure in bald eagles in Wyoming during the big game hunting season, the influx of eagles into our study area during the hunt, the geographic origins of eagles exposed to lead, and the efficacy of using non-lead rifle ammunition to reduce lead in eagles. We tested 81 blood samples from bald eagles before, during and after the big game hunting seasons in 2005-2010, excluding 2008, and found eagles had significantly higher lead levels during the hunt. We found 24% of eagles tested had levels indicating at least clinical exposure (>60 ug/dL) during the hunt while no birds did during the non-hunting seasons. We performed driving surveys from 2009-2010 to measure eagle abundance and found evidence to suggest that eagles are attracted to the study area during the hunt. We fitted 10 eagles with satellite transmitters captured during the hunt and all migrated south after the cessation of the hunt. One returned to our study area while the remaining nine traveled north to summer/breed in Canada. The following fall, 80% returned to our study area for the hunting season, indicating that offal provides a seasonal attractant for eagles. We fitted three local breeding eagles with satellite transmitters and none left their breeding territories to feed on offal during the hunt, indicating that lead ingestion may be affecting migrants to a greater degree. During the 2009 and 2010 hunting seasons we provided non-lead rifle ammunition to local hunters and recorded that 24% and 31% of successful hunters used non-lead ammunition, respectively. We found the use of non-lead ammunition significantly reduced lead exposure in eagles, suggesting this is a viable solution to reduce lead exposure in eagles.

  18. E-Waste Informal Recycling: An Emerging Source of Lead Exposure in South America.

    PubMed

    Pascale, Antonio; Sosa, Adriana; Bares, Cristina; Battocletti, Alejandra; Moll, María José; Pose, Darío; Laborde, Amalia; González, Hugo; Feola, Gabriella

    2016-01-01

    Primitive electronic waste (e-waste) recycling creates exposures to several hazardous substances including lead. In Uruguay, primitive recycling procedures are a significant source of lead exposure. The aim of this study was to examine lead exposure in blood lead levels (BLLs) in low-income children exposed to lead through burning cables. A sample of children and adolescents exposed to lead through burning cable activities were assessed at the Department of Toxicology in Montevideo, Uruguay, between 2010 and 2014. Soil lead levels of residences were taken shortly after their assessment. The final sample included 69 children and adolescents (mean age 7.89 years). More than 66% of participants had an additional source of lead exposure-manual gathering of metals-and <5% were exposed to lead through landfills or paint. Average BLLs at first consultation were 9.19 ug/dL and lower at the second measurement (5.86 μg/dL). Data from soil lead levels ranged from 650 to 19,000 mg of lead/kg of soil. The interventions conducted after the assessment included family education in the clinic and at home, indoor and outdoor remediation. We found a decrease in BLLs of 6.96 μg/dL. Older children had lower BLLs (r = -0.24; P = 0.05). Statistical analyses also showed that children living in areas with higher soil lead levels had significantly higher BLLs (r = 0.50; P < 0.01). Additionally, we found greater BLLs from burning cable activities when children had been exposed to lead-based paint (r = 0.23; P < 0.1). Among children exposed to e-waste recycling, the most common additional source of lead exposure was the manual gathering of metals. The average BLL among children and adolescents in this study is higher than the BLLs currently suggested in medical intervention. Future research should focus on exploring effective interventions to reduce lead exposure among this vulnerable group. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  19. Effects of chronic exposure to sublethal concentrations of lead acetate on heme synthesis and immune function in red-tailed hawks.

    PubMed

    Redig, P T; Lawler, E M; Schwartz, S; Dunnette, J L; Stephenson, B; Duke, G E

    1991-07-01

    Red-tailed hawks were exposed to sublethal levels of lead acetate for periods of 3 or 11 weeks. Alterations in the heme biosynthetic pathway were demonstrated after the first week of exposure to 0.82 mg lead per kilogram body weight per day. Activity of erythrocyte porphobilinogen synthase (aminolevulinic acid dehydratase) was depressed significantly and did not return to normal levels until 5 weeks after the termination of lead treatments. A rapid and relatively brief increase in erythrocyte free protoporphyrin and a slower but more prolonged increase in its zinc complex were also demonstrated with exposure to this dose of lead for 3 weeks. Less substantial decreases in hematocrit and hemoglobin levels occurred but only in the longer experiment with exposure to higher lead levels. Short term, low level lead exposure did not effect immune function significantly in the hawks, as measured by antibody titers to foreign red blood cells or by the mitogenic stimulation of T-lymphocytes. Increased lead exposure produced a significant decrease in the mitogenic response but had no effect on antibody titers.

  20. Brainstem auditory evoked potentials in children with low level cumulative lead exposure

    PubMed Central

    Alvarenga, Kátia F.; Morata, Thais C.; Lopes, Andréa Cintra; Feniman, Mariza Ribeiro; Corteletti, Lilian Cássia Bórnia Jacob

    2015-01-01

    Introduction Earlier studies have demonstrated an auditory effect of lead exposure in children,but information on the effects of low chronic exposures needs to be further elucidated. Objective To investigate the effect of low chronic exposures of the auditory system in childrenwith a history of low blood lead levels, using an auditory electrophysiological test. Methods Contemporary cross-sectional cohort. Study participants underwent tympanometry, pure tone and speech audiometry, transient evoked otoacoustic emissions, and brainstem auditory evoked potentials, with blood lead monitoring over a period of 35.5 months. The study included 130 children, with ages ranging from 18 months to 14 years, 5 months (mean age 6years, 8 months ± 3 years, 2 months). Results The mean time-integrated cumulative blood lead index was 12 g/dL (SD ± 5.7, range:2.433). All participants had hearing thresholds equal to or below 20 dBHL and normal amplitudes of transient evoked otoacoustic emissions. No association was found between the absolute latencies of waves I, III, and V, the interpeak latencies I---III, III---V, and I---V, and the cumulative lead values. Conclusion No evidence of toxic effects from chronic low lead exposures was observed on the auditory function of children living in a lead contaminated area. PMID:25458254

  1. Assessment of lead exposures in three radiator repair shops. Final report

    SciTech Connect

    Piacitelli, G.M.

    1992-06-10

    In an attempt to determine worker exposure to lead (7439921) in radiator repair shops, area and personal sampling was performed at three locations in Cincinnati, Ohio. Altogether, 129 air samples and 126 wipe samples were collected. The highest air concentrations were near the repair stations where mechanics work with molten lead based solder. Two shops used local exhaust ventilation and had effectively controlled worker exposure to airborne lead. Exposures in a third shop where there was no local ventilation were frequently above the permissible exposure limit (50 micrograms/cubic meter). Lead contamination on work surfaces was as high as 500,000 micrograms/square meter. Lead was also found in lunch areas, on the hands of workers before and after washing, on street shoes and in personal vehicles. The author recommended steps to be taken to reduce the contamination level, including the installation of an effective local exhaust ventilation system, the mandatory use of protective equipment, a strict adherence to personal and environmental hygiene, an enforced prohibition of eating and smoking in all lead contaminated areas, the implementation of routine environmental and medical monitoring programs, and training to increase the awareness of the problems associated with using lead.

  2. Reduction in operator radiation exposure during transradial catheterization and intervention using a simple lead drape.

    PubMed

    Iqtidar, Ali F; Jeon, Cathy; Rothman, Richard; Snead, Randall; Pyne, Christopher T

    2013-03-01

    Transradial access for cardiac catheterization and intervention is a recognized method for reducing complications and improving patient comfort. However, there are concerns over possible increased operator radiation exposure. We tested the hypothesis that a simple lead drape would reduce operator exposure in transradial procedures. Patients undergoing either diagnostic or interventional procedures using transradial access were assigned in an alternating manner to the use of a 0.5-mm lead apron across the patient's abdomen in addition to standard operator protection. Patients were divided into 4 groups: (left enhanced shielding vs left standard shielding; right enhanced shielding vs right standard shielding). Dosimeters were taped to the primary and secondary operators' left wrist and outside the thyroid guard. The operator exposure was measured for each site on every case in centigray. In standard shielded patients, there was no increase in operator exposure between the left and right approach patients at any measurement site. Measured exposure was reduced with enhanced shielding at all dosimeter sites except the secondary operator's collar (both left and right) and the primary operator's collar from the right. There was no significant difference in fluoroscopy, air kerma, or dose area product between standard and enhanced shielded patients. The use of a lead drape reduces the rate of operator radiation exposure at multiple measurement sites. Use of the left radial approach was not associated with an increase in operator exposure compared with the right radial approach. Copyright © 2013 Mosby, Inc. All rights reserved.

  3. Novel protective lead shield and pulse fluoroscopy can reduce radiation exposure during the ERCP procedure.

    PubMed

    Kurihara, Toshio; Itoi, Takao; Sofuni, Atsushi; Itokawa, Fumihide; Tsuchiya, Takayoshi; Ishii, Kentaro; Tsuji, Shujiro; Ikeuchi, Nobuhito; Moriyasu, Fuminori

    2012-05-01

    ERCP-related procedures involve radiation exposure of patients and medical staff. We developed a novel protective lead shield which is attached around the fluoroscopy generator. Here we examine levels of radiation exposure to patients, endoscopists and assistants, and evaluate the usefulness of the newly designed protective shield. Four-hundred and seventy-one ERCP procedures were performed from April 2006 to April 2007. At first, we compared the radiation dose of consecutive fluoroscopy conditions with pulse fluoroscopy of 15 per second and then the radiation dose with and without the protective shield. Next, we measured the radiation exposure of endoscopists and assistants in the clinical setting monitored by digital dosimeter during ERCP procedure. The radiation dose was the most at the 45° direction. Using pulse fluoroscopy of 15 per second the radiation dose of patients and endoscopists decreased by about half. Using both pulse fluoroscopy of 15 per second and the protective shield, the radiation dose at the endoscopist's position was reduced up to 97%. The total fluoroscopy time was 5851 minutes in the 471 ERCP cases. Using pulse 15 and the protective lead shield, the radiation exposure dose of one endoscopist and two assistants were 2430.8, 2673.9 and 1375.0µSv, respectively. Novel protective lead shield in combination with pulse fluoroscopy can significantly reduce the radiation exposure leading to avoid unnecessary radiation exposure to patients and medical staff.

  4. [Status of lead exposure and its impact on health of workers in an accumulator factory].

    PubMed

    Liang, Jiabin; Zhang, Jian; Guo, Xiaojing; Mai, Jianping; Wang, Zhi; Liu, Yimin

    2014-02-01

    To identify the occupational hazard factors in an accumulator factory, to analyze the status of internal and external lead exposure and evaluate the impact of lead exposure on the health of workers in the accumulator industry, and to provide a theoretical basis for improved lead exposure criteria and technical support for the control of lead contamination in the accumulator industry. An on-site investigation was carried out to monitor and evaluate the lead fume and dust in the workplaces of an accumulator factory, and occupational health examination was performed in all workers. The occupational hazard safeguards in the accumulator factory were unadvanced. The contamination of lead fume and dust was serious. The abnormal rate of blood lead was up to 79.80%, and many workers developed anemia and mild peripheral nerve disease. Lead contamination is serious in the accumulator factory, leading to poor health of workers. It is essential to take effective control measures, improve the working environment, provide occupational health education, increase workers' self-protection awareness, and periodically conduct occupational hazard monitoring and health surveillance. The government must reinforce occupational health supervision of such enterprises.

  5. Staff exposure to pulsed magnetic fields during depression treatment with transcranial magnetic stimulation.

    PubMed

    Møllerløkken, Ole Jacob; Stavang, Helen; Hansson Mild, Kjell

    2017-03-01

    Transcranial magnetic stimulation or repetitive transcranial magnetic stimulation (TMS/rTMS) are currently used in research and treatments of diseases of the central nervous system, such as recurring depression. Strong electric pulses are used to produce strong pulsed magnetic fields that are directed to the patient's cerebral cortex where the fields induce electric pulses. The pulses may be causing unnecessary exposure of the staff. The MagVenture TMS/rTMS system was investigated, without patient presence, through measurements of magnetic field pulses at varying distances from the emitting coil and different power settings (94-127 A/s). Fourteen measurements were done which displayed exposures exceeding the given guidelines up until a distance of 40 cm from the transmitting coil. The study shows that the exposure of staff in this type of treatment may exceed the given guidelines for occupational exposure, thus confirming previous findings. This necessitates good routines in information and treatment procedures to avoid this exposure.

  6. Longitudinal analyses of prenatal and postnatal lead exposure and early cognitive development

    SciTech Connect

    Bellinger, D.; Leviton, A.; Waternaux, C.; Needleman, H.; Rabinowitz, M.

    1987-04-23

    In a prospective cohort study of 249 children from birth to two years of age, we assessed the relation between prenatal and postnatal lead exposure and early cognitive development. On the basis of lead levels in umbilical-cord blood, children were assigned to one of three prenatal-exposure groups: low (less than 3 micrograms per deciliter), medium (6 to 7 micrograms per deciliter), or high (greater than or equal to 10 micrograms per deciliter). Development was assessed semiannually, beginning at the age of six months, with use of the Mental Development Index of the Bayley Scales of Infant Development (mean +/- SD, 100 +/- 16). Capillary-blood samples obtained at the same times provided measures of postnatal lead exposure. Regression methods for longitudinal data were used to evaluate the association between infants' lead levels and their development scores after adjustment for potential confounders. At all ages, infants in the high-prenatal-exposure group scored lower than infants in the other two groups. The estimated difference between the overall performance of the low-exposure and high-exposure groups was 4.8 points (95 percent confidence interval, 2.3 to 7.3). Between the medium- and high-exposure groups, the estimated difference was 3.8 points (95 percent confidence interval, 1.3 to 6.3). Scores were not related to infants' postnatal blood lead levels. It appears that the fetus may be adversely affected at blood lead concentrations well below 25 micrograms per deciliter, the level currently defined by the Centers for Disease Control as the highest acceptable level for young children.

  7. Low-level exposure to lead, blood pressure, and hypertension in a population-based cohort.

    PubMed

    Gambelunghe, Angela; Sallsten, Gerd; Borné, Yan; Forsgard, Niklas; Hedblad, Bo; Nilsson, Peter; Fagerberg, Björn; Engström, Gunnar; Barregard, Lars

    2016-08-01

    Environmental lead exposure is a possible causative factor for increased blood pressure and hypertension, but large studies at low-level exposure are scarce, and results inconsistent. We aimed to examine the effects of environmental exposure to lead in a large population-based sample. We assessed associations between blood lead and systolic/diastolic blood pressure and hypertension in 4452 individuals (46-67 years) living in Malmö, Sweden, in 1991-1994. Blood pressure was measured using a mercury sphygmomanometer after 10min supine rest. Hypertension was defined as high systolic (≥140mmHg) or diastolic (≥90mmHg) blood pressure and/or current use of antihypertensive medication. Blood lead was calculated from lead in erythrocytes and haematocrit. Multivariable associations between blood lead and blood pressure or hypertension were assessed by linear and logistic regression. Two-thirds of the cohort was re-examined 16 years later. At baseline, mean blood pressure was 141/87mmHg, 16% used antihypertensive medication, 63% had hypertension, and mean blood lead was 28µg/L. Blood lead in the fourth quartile was associated with significantly higher systolic and diastolic blood pressure (point estimates: 1-2mmHg) and increased prevalence of hypertension (odds ratio: 1.3, 95% confidence interval: 1.1-1.5) versus the other quartiles after adjustment for sex, age, smoking, alcohol, waist circumference, and education. Associations were also significant with blood lead as a continuous variable. Blood lead at baseline, having a half-life of about one month, was not associated with antihypertensive treatment at the 16-year follow-up. Low-level lead exposure increases blood pressure and may increase the risk of hypertension. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  8. The burden of disease from pediatric lead exposure at hazardous waste sites in 7 Asian countries.

    PubMed

    Caravanos, Jack; Chatham-Stephens, Kevin; Ericson, Bret; Landrigan, Philip J; Fuller, Richard

    2013-01-01

    Identification and systematic assessment of hazardous wastes sites in low and middle-income countries has lagged. Hazardous waste problems are especially severe in lower income Asian countries where environmental regulations are non-existent, nonspecific or poorly enforced. In these countries extensive unregulated industrial development has created waste sites in densely populated urban areas. These sites appear to pose significant risks to public health, and especially to the health of children. To assess potential health risks from chemical contamination at hazardous waste sites in Asia, we assessed 679 sites. A total of 169 sites in 7 countries were classified as contaminated by lead. Eighty-two of these sites contained lead at levels high enough to produce elevated blood lead levels in surrounding populations. To estimate the burden of pediatric lead poisoning associated with exposure to lead in soil and water at these 82 lead-contaminated sites, we used standard toxicokinetic models that relate levels of lead in soil and water to blood lead levels in children. We calculated blood lead levels, and we quantified losses of intelligence (reductions in IQ scores) that were attributable to lead exposure at these sites. We found that 189,725 children in the 7 countries are at risk of diminished intelligence as a consequence of exposure to elevated levels of lead in water and soil at hazardous waste sites. Depending on choice of model, these decrements ranged from 4.94 to 14.96 IQ points. Given the restricted scope of this survey and the conservative estimation procedures employed, this number is almost certainly an underestimate of the full burden of disease. Exposure to toxic chemicals from hazardous waste sites is an important and heretofore insufficiently examined contributor to the Global Burden of Disease.

  9. Urinary KIM-1: a novel biomarker for evaluation of occupational exposure to lead

    PubMed Central

    Zhou, Rong; Xu, Yahong; Shen, Jie; Han, Lin; Chen, Xi; Feng, Xuefang; Kuang, Xingya

    2016-01-01

    Chronic occult lead poisoning often develops ensuing occupational lead exposure. Early diagnosis of lead poisoning is critical for timely discontinuation of lead exposure and for prognosis. This study explored the value of urinary kidney injury molecule-1 (KIM-1) in diagnosing renal injury induced by lead at an early stage. We retrospectively analyzed 92 workers exposed to occupational lead and demonstrated a better correlation ship between blood lead levels and urine excretion of KIM-1 than other traditional renal injury biomarkers following creatinine adjustment. Receiver operating characteristic curve analysis of the ability of diverse biomarkers for predicting kidney injury in lead-exposed workers demonstrated that the order of predicting accuracy of the studied biomarkers is as follows: urinary KIM-1-to-creatinine ratio > urinary N-acetyl-β-(D)-glucosaminidase-to-creatinine ratio > urinary β2-microglobulin-to-creatinine ratio > urinary α1-microglobulin-to-creatinine ratio, with the Youden index being 16.59 ng/g, 14.01 U/g, 0.15 mg/g, and 4.63 mg/g, respectively. Collectively, our findings suggest that short-period occupational lead exposure may cause injury of renal tubules. Urinary excretion of KIM-1 correlates with blood lead levels better than other traditional renal injury biomarkers, including N-acetyl-β-(D)-glucosaminidase, α1-microglobulin, and β2-microglobulin. Longitudinal surveillance of urinary KIM-1 may aid for early diagnosis of renal tubular injury in workers with occupational lead exposure. PMID:27966578

  10. A target-specific electrode and lead design for internal globus pallidus deep brain stimulation.

    PubMed

    Vasques, Xavier; Cif, Laura; Mennessier, Gérard; Coubes, Philippe

    2010-01-01

    In nearly all deep brain stimulation (DBS) applications, the same quadripolar electrode design is used for different anatomical targets even if shape and volume differences exist between nuclei. Taking into account the electrode location within the internal globus pallidus (GPi) and the size of the GPi, 2 electrodes were designed in order to improve the therapeutic benefit, to minimize side effects from DBS and to obtain a more homogeneous electric field distribution. The electrodes were evaluated numerically by using a stereotactic model measuring the correlation between the electric field and the GPi. The model was applied to 26 dystonodyskinetic patients who underwent surgery for a bilateral lead implantation into the posteroventral part of the GPi. The designed electrodes produced a more homogeneous distribution of the electric field than the quadripolar electrode.

  11. The health impact of environmental pollutants: a special focus on lead exposure in South Africa.

    PubMed

    Harper, Carolyn C; Mathee, Angela; von Schirnding, Yasmin; De Rosa, Christopher T; Falk, Henry

    2003-08-01

    Studies have shown blood lead levels of some children in South Africa at levels of health concern. New studies show even relatively low lead levels to have detrimental effects on cognitive function in young children. Large numbers of South African inner-city and other children have been shown to have unacceptably high blood lead levels. Studies indicate that blood lead levels of children living in South Africa's urban areas are higher than those of children in most developed countries, including Great Britain, Europe, and the United States. Although data and reported studies are very sparse, mean blood lead levels of approximately 15 microg/dl have been reported in children. Elevated blood lead levels were associated with socioeconomic status and housing conditions. Key environmental risk factors for elevated blood levels were contaminated soil and dust in the urban environment, and the still large number of automobiles using leaded gasoline. In view of emerging evidence linking lead at increasingly lower levels to adverse effects in children, the South African government is taking actions to reduce lead exposure among vulnerable groups. Currently, South Africa has no national lead surveillance program. The government, therefore, has developed international and regional partnerships to prevent and address the problem of lead exposure.

  12. Environmental urban lead exposure and blood levels in children of Mexico City

    SciTech Connect

    Romieu, I.; Carreon, T.; Lopez, L.

    1995-11-01

    Lead contamination is now a leading public health problem in Mexico. However, there are few data on the lead content of various environmental sources, and little is known about the contribution of these sources to the total lead exposure in the population of children residing in Mexico City. We conducted a cross-sectional study in a random sample of 200 children younger than 5 years of age who lived in one of two areas of Mexico City. Environmental samples of floor, window, and street dust, paint, soil water, and glazed ceramics were obtained from the participants` households, as well as blood samples and dirt from the hands of the children. Blood lead levels ranged from 1 to 31 {mu}g/dl with a mean of 9.9 {mu}g/dl (SD 5.8 {mu}/dl). Forty-four percent of the children 18 months of age or older had blood lead levels exceeding 10 {mu}g/dl. The lead content of environmental samples was low, except in glazed ceramic. The major predictors of blood lead levels were the lead content of the glazed ceramics used or prepare children`s food, exposure to airborne lead due to vehicular emission, and the lead content of the dirt from the children`s hands. We conclude that the major sources of lead exposure in Mexico City could be controlled by adequate public health programs to reinforce the use of unleaded gasoline and to encourage production and use of unleaded cookware instead of lead-glazed ceramics. 18 refs., 5 tabs.

  13. Effects of occupational exposure to lead on left ventricular echocardio graphic variables.

    PubMed

    Taheri, Ladan; Sadeghi, Masoumeh; Sanei, Hamid; Rabiei, Katayoun; Arabzadeh, Somayeh; Sarrafzadegan, Nizal

    2012-01-01

    Lead contamination can affect many body organs including the heart. This study assessed a number of echocardiographic indices to clarify the effects of lead on cardiac function among battery factory workers who are in constant exposure to lead. In a cross-sectional study, 142 male battery factory workers who had been exposed to lead for at least 1 year were evaluated. The subjects aged 25-55 years old and were excluded if they had hypertension, diabetes, or cardiovascular diseases. Demographic characteristics, professional profile, lead exposure, history of respiratory diseases, drugs intake, and lifestyle information of the participants were collected. Height, weight and blood pressure measurements were then performed. Blood tests were also ordered to determine blood lead levels. The subjects finally underwent M-mode and Doppler echocardiography. Linear regression analysis was used to establish the effects of lead on the target indices. All statistical analyses were conducted in SPSS18. The mean age and mean duration of lead exposure of the subjects were 41.78 ± 13.58 and 23.54 ± 14.44 years, respectively. The mean blood lead level was 7.59 ± 2.75 µg/dl. Left ventricular hypertrophy was detected in 12% of the participants. Blood lead levels were not significantly related with echocardiographic indices in the crude model or after adjustments for age alone or for age and other risk factors. Blood lead levels of our participants were below standard values. In addition, no significant relation was found between left ventricular function indices and blood lead levels. The absence of such relations could have been caused by the exclusion of individuals with hypertension or cardiovascular diseases. Structural modifications in battery factories following legislations in Iran might have been responsible for low blood lead levels among the subjects.

  14. Lead exposure and semen quality among traffic police in Arequipa, Peru.

    PubMed

    Eibensteiner, Lynn; Del Carpio Sanz, Ada; Frumkin, Howard; Gonzales, Carla; Gonzales, Gustavo F

    2005-01-01

    This study examined lead exposure (n = 43) and semen quality (n = 18) among traffic police officers in Arequipa, Peru, where leaded gasoline is used. Blood lead (PbB) was measured using atomic absorption spectrophotometry, and semen was analyzed following World Health Organization (WHO) protocol. Mean PbB was 48.5 microg/dL. Although current PbB was associated with declines in several semen parameters (sperm morphology, concentration and total number of sperm), only sperm motility and viability differed significantly between the < or = 40 microg/dL and > 40 microg/dL categories, and decreased with increasing PbB in simple linear regression. Traffic police are an indicator group for excessive ambient lead exposure, and these results support earlier findings on the male reproductive toxicity of lead. The results should be interpreted cautiously since the numbers were small and the analysis was unable to control for all potential confounders due to incomplete data.

  15. Renal responses to acute lead waterborne exposure in the freshwater rainbow trout (Oncorhynchus mykiss).

    PubMed

    Patel, Monika; Rogers, Joseph T; Pane, Eric F; Wood, Chris M

    2006-12-30

    The possible nephrotoxic effects of waterborne lead exposure (as Pb(NO3)2) were investigated in the freshwater rainbow trout (Oncorhynchus mykiss). Kidney lead accumulation was time-dependent, increasing upon exposure to 0.57+/-0.01 mg dissolved Pb L(-1) for up to 96 h with a significantly higher burden occurring in the posterior kidney compared to the anterior segment. Urine analyses in trout exposed to 1.20+/-0.09 mg dissolved Pb L(-1) revealed a significant increase in urinary lead excretion rate throughout 96 h of exposure. Urine flow rate and glomerular filtration rate (GFR) were not impacted with the exception of a significant decrease in GFR from 84 to 96 h in lead-exposed trout. Urine pH decreased significantly over time in lead-exposed fish. Correspondingly, urine ammonia excretion rate showed a marked increase from 48 h onwards. In experimental fish, urine glucose excretion was significantly greater by 96 h while urine lactate, urea and protein excretion were not significantly altered by lead exposure. The urine excretion rate of Ca2+ increased significantly by approximately 43% after only 24 h of lead exposure, and was maintained at a higher rate than controls for up to 96 h. Magnesium excretion increased in a time-dependent fashion, reaching a two- to three-fold rise by 96 h. In contrast, rates of Na+ and Cl- excretion were decreased in experimental fish by approximately 30% by 48 h, this trend continuing for the duration of lead-exposure. There were no changes in any of these parameters in similarly treated control fish. Clearance ratio analyses indicated progressive decreases in the net reabsorption efficiencies of the renal system for Ca2+, Mg2+, Pb, and glucose, suggesting that the active tubular transport mechanisms for these substances were inhibited by lead exposure, while Na+, K+, Cl-, lactate, and protein reabsorptions were unaffected. Net ammonia secretion increased. We conclude that changes in renal function both reflect and help to minimize

  16. Economic Costs of Childhood Lead Exposure in Low- and Middle-Income Countries

    PubMed Central

    Trasande, Leonardo

    2013-01-01

    Background: Children’s blood lead levels have declined worldwide, especially after the removal of lead in gasoline. However, significant exposure remains, particularly in low- and middle-income countries. To date, there have been no global estimates of the costs related to lead exposure in children in developing countries. Objective: Our main aim was to estimate the economic costs attributable to childhood lead exposure in low- and middle-income countries. Methods: We developed a regression model to estimate mean blood lead levels in our population of interest, represented by each 1-year cohort of children < 5 years of age. We used an environmentally attributable fraction model to estimate lead-attributable economic costs and limited our analysis to the neurodevelopmental impacts of lead, assessed as decrements in IQ points. Our main outcome was lost lifetime economic productivity due to early childhood exposure. Results: We estimated a total cost of $977 billions of international dollars in low- and middle-income countries, with economic losses equal to $134.7 billion in Africa [4.03% of gross domestic product (GDP)], $142.3 billion in Latin America and the Caribbean (2.04% of GDP), and $699.9 billion in Asia (1.88% of GDP). Our sensitivity analysis indicates a total economic loss in the range of $728.6–1162.5 billion. Conclusions: We estimated that, in low- and middle-income countries, the burden associated with childhood lead exposure amounts to 1.20% of world GDP in 2011. For comparison, in the United States and Europe lead-attributable economic costs have been estimated at $50.9 and $55 billion, respectively, suggesting that the largest burden of lead exposure is now borne by low- and middle-income countries. Citation: Attina TM, Trasande L. 2013. Economic costs of childhood lead exposure in low- and middle-income countries. Environ Health Perspect 121:1097–1102; http://dx.doi.org/10.1289/ehp.1206424 PMID:23797342

  17. Contaminated Turmeric Is a Potential Source of Lead Exposure for Children in Rural Bangladesh

    PubMed Central

    Gleason, Kelsey; Shine, James P.; Shobnam, Nadia; Rokoff, Lisa B.; Suchanda, Hafiza Sultana; Ibne Hasan, Md Omar Sharif; Mostofa, Golam; Amarasiriwardena, Chitra; Quamruzzaman, Quazi; Rahman, Mahmuder; Kile, Molly L.; Bellinger, David C.; Christiani, David C.; Wright, Robert O.; Mazumdar, Maitreyi

    2014-01-01

    Background. During the conduct of a cohort study intended to study the associations between mixed metal exposures and child health outcomes, we found that 78% of 309 children aged 20–40 months evaluated in the Munshiganj District of Bangladesh had blood lead concentrations ≥5 µg/dL and 27% had concentrations ≥10 µg/dL. Hypothesis. Environmental sources such as spices (e.g., turmeric, which has already faced recalls in Bangladesh due to high lead levels) may be a potential route of lead exposure. Methods. We conducted visits to the homes of 28 children randomly selected from among high and low blood lead concentration groups. During the visits, we administered a structured questionnaire and obtained soil, dust, rice, and spice samples. We obtained water samples from community water sources, as well as environmental samples from neighborhood businesses. Results. Lead concentrations in many turmeric samples were elevated, with lead concentrations as high as 483 ppm. Analyses showed high bioaccessibility of lead. Conclusions. Contamination of turmeric powder is a potentially important source of lead exposure in this population. PMID:25214856

  18. Contaminated turmeric is a potential source of lead exposure for children in rural Bangladesh.

    PubMed

    Gleason, Kelsey; Shine, James P; Shobnam, Nadia; Rokoff, Lisa B; Suchanda, Hafiza Sultana; Ibne Hasan, Md Omar Sharif; Mostofa, Golam; Amarasiriwardena, Chitra; Quamruzzaman, Quazi; Rahman, Mahmuder; Kile, Molly L; Bellinger, David C; Christiani, David C; Wright, Robert O; Mazumdar, Maitreyi

    2014-01-01

    During the conduct of a cohort study intended to study the associations between mixed metal exposures and child health outcomes, we found that 78% of 309 children aged 20-40 months evaluated in the Munshiganj District of Bangladesh had blood lead concentrations ≥5 µg/dL and 27% had concentrations ≥10 µg/dL. Environmental sources such as spices (e.g., turmeric, which has already faced recalls in Bangladesh due to high lead levels) may be a potential route of lead exposure. We conducted visits to the homes of 28 children randomly selected from among high and low blood lead concentration groups. During the visits, we administered a structured questionnaire and obtained soil, dust, rice, and spice samples. We obtained water samples from community water sources, as well as environmental samples from neighborhood businesses. Lead concentrations in many turmeric samples were elevated, with lead concentrations as high as 483 ppm. Analyses showed high bioaccessibility of lead. Contamination of turmeric powder is a potentially important source of lead exposure in this population.

  19. Delayed blood regeneration in lead exposure: An effect on reserve capacity

    SciTech Connect

    Grandjean, P.; Jensen, B.M.; Sando, S.H.; Jogensen, P.J.; Antonsen, S. )

    1989-10-01

    Twenty-five lead-exposed Danish battery production workers and 25-age-matched controls were examined to evaluate subclinical effects on blood formation. Blood lead levels averaged 2.14 mumol/L and 0.35 mumol/L in the two groups; the lead workers also showed high levels of erythrocyte protoporphyrin, as compared to the controls. Otherwise, the hematological parameters indicated an appropriate iron status and no other deviations. From all subjects, 0.45 L of blood was bled as part of a normal blood donation. Five and 11 days later, reticulocyte counts were significantly higher in the control group than in the lead-exposed workers. On day 15, the lead workers showed a significant delay in blood regeneration, as evidenced by lower hemoglobin concentration, and erythrocyte and reticulocyte counts. The lead exposure in the present study was within legal limits, and lead-induced anemia would be expected only at much higher exposure levels. Thus, despite the normal hematological findings in the initial examination, the lead exposure caused a decreased reserve capacity for blood formation, and this effect became evident only after the blood loss.

  20. E-Waste Informal Recycling: An Emerging Source of Lead Exposure in South America

    PubMed Central

    Pascale, Antonio; Sosa, Adriana; Bares, Cristina; Battocletti, Alejandra; Moll, María José; Pose, Darío; Laborde, Amalia; González, Hugo; Feola, Gabriella

    2016-01-01

    BACKGROUND Primitive electronic waste (e-waste) recycling creates exposures to several hazardous substances including lead. In Uruguay, primitive recycling procedures are a significant source of lead exposure. OBJECTIVES The aim of this study was to examine lead exposure in blood lead levels (BLLs) in low-income children exposed to lead through burning cables. METHODS A sample of children and adolescents exposed to lead through burning cable activities were assessed at the Department of Toxicology in Montevideo, Uruguay, between 2010 and 2014. Soil lead levels of residences were taken shortly after their assessment. FINDINGS The final sample included 69 children and adolescents (mean age 7.89 years). More than 66% of participants had an additional source of lead exposure—manual gathering of metals—and <5% were exposed to lead through landfills or paint. Average BLLs at first consultation were 9.19 ug/dL and lower at the second measurement (5.86 μg/dL). Data from soil lead levels ranged from 650 to 19,000 mg of lead/kg of soil. The interventions conducted after the assessment included family education in the clinic and at home, indoor and outdoor remediation. We found a decrease in BLLs of 6.96 μg/dL. Older children had lower BLLs (r = −0.24; P =0.05). Statistical analyses also showed that children living in areas with higher soil lead levels had significantly higher BLLs (r = 0.50; P < 0.01). Additionally, we found greater BLLs from burning cable activities when children had been exposed to lead-based paint (r = 0.23; P < 0.1). CONCLUSION Among children exposed to e-waste recycling, the most common additional source of lead exposure was the manual gathering of metals. The average BLL among children and adolescents in this study is higher than the BLLs currently suggested in medical intervention. Future research should focus on exploring effective interventions to reduce lead exposure among this vulnerable group. PMID:27325077

  1. Developmental lead exposure impairs contextual fear conditioning and reduces adult hippocampal neurogenesis in the rat brain.

    PubMed

    Jaako-Movits, Külli; Zharkovsky, Tamara; Romantchik, Olga; Jurgenson, Monika; Merisalu, Eda; Heidmets, Lenne-Triin; Zharkovsky, Alexander

    2005-11-01

    The effects of developmental lead exposure on the emotional reactivity, contextual fear conditioning and neurogenesis in the dentate gyrus of 60-80 days-old rats were studied. Wistar rat pups were exposed to 0.2% lead acetate via their dams' drinking water from postnatal day (PND) 1 to PND 21 and directly via drinking water from weaning until PND 30. At PND 60 and 80 the level of anxiety and contextual fear conditioning were studied, respectively. At PND 80 all animals received injections of BrdU to determine the effects of Pb on the generation of new cells in the dentate gyrus of hippocampus and on their survival and differentiation patterns. The results of the present study demonstrate that developmental lead exposure induces persistent increase in the level of anxiety and inhibition of contextual fear conditioning. Developmental lead exposure reduced generation of new cells in the dentate gyrus and altered the pattern of differentiation of BrdU-positive cells into mature neurons. A lower proportion of BrdU-positive cells co-expressed with the marker for mature neurons, calbindin. In contrast, the proportions of young not fully differentiated neurons and proportions of astroglial cells, generated from newly born cells, were increased in lead-exposed animals. Our results demonstrate that developmental lead exposure induces persistent inhibition of neurogenesis and alters the pattern of differentiation of newly born cells in the dentate gyrus of rat hippocampus, which could, at least partly, contribute to behavioral and cognitive impairments observed in adulthood.

  2. Association between subchronic and chronic lead exposure and levels of antioxidants and chemokines.

    PubMed

    Dobrakowski, Michał; Kasperczyk, Aleksandra; Pawlas, Natalia; Birkner, Ewa; Hudziec, Edyta; Chwalińska, Ewa; Kasperczyk, Sławomir

    2016-10-01

    This study aimed to compare the influence of lead on the non-enzymatic antioxidant defenses and the levels of chemokines in workers subchronically and chronically exposed to lead. The study population was divided into three groups. The first group consisted of male workers subchronically exposed to lead for 40 ± 3.2 days, while the second group included male workers chronically exposed to lead. The third group was a control group. The levels of uric acid and bilirubin were significantly higher after a subchronic exposure to lead compared to the baseline by 22 and 35 %, respectively. Similarly, the values of total antioxidant capacity (TAC), total oxidant status (TOS), and oxidative stress index (OSI) increased by 15, 50, and 33 %, respectively. At the same time, the levels of thiol groups and albumin decreased by 5 and 8 %, respectively. Additionally, the levels of interleukin-8 (IL-8) and macrophage inflammatory protein-1β (MIP-1β) were significantly higher after a subchronic exposure to lead compared to the baseline by 34 and 20 %, respectively. Moreover, IL-8 level was significantly higher by 40 % in the group of workers chronically exposed to lead than in the control group, while the level of interferon gamma-induced protein-10 (IP-10) was significantly lower by 28 %. Similar to chronic lead exposure, subchronic exposure to lead is associated with elevated blood levels of uric acid and bilirubin in humans. This probably results in increased TAC value despite thiol depletion. However, the compensatory activation of non-enzymatic antioxidant defenses seems to be insufficient to protect against lead-induced oxidative stress, which may be additively enhanced by the pro-inflammatory action of chemokines, especially IL-8.

  3. Sex-based differences in gene expression in hippocampus following postnatal lead exposure.

    PubMed

    Schneider, J S; Anderson, D W; Sonnenahalli, H; Vadigepalli, R

    2011-10-15

    The influence of sex as an effect modifier of childhood lead poisoning has received little systematic attention. Considering the paucity of information available concerning the interactive effects of lead and sex on the brain, the current study examined the interactive effects of lead and sex on gene expression patterns in the hippocampus, a structure involved in learning and memory. Male or female rats were fed either 1500 ppm lead-containing chow or control chow for 30 days beginning at weaning.Blood lead levels were 26.7±2.1 μg/dl and 27.1±1.7 μg/dl for females and males, respectively. The expression of 175 unique genes was differentially regulated between control male and female rats. A total of 167 unique genes were differentially expressed in response to lead in either males or females. Lead exposure had a significant effect without a significant difference between male and female responses in 77 of these genes. In another set of 71 genes, there were significant differences in male vs. female response. A third set of 30 genes was differentially expressed in opposite directions in males vs. females, with the majority of genes expressed at a lower level in females than in males. Highly differentially expressed genes in males and females following lead exposure were associated with diverse biological pathways and functions. These results show that a brief exposure to lead produced significant changes in expression of a variety of genes in the hippocampus and that the response of the brain to a given lead exposure may vary depending on sex. Copyright © 2011 Elsevier Inc. All rights reserved.

  4. Lead exposure of waterfowl ingesting Coeur d?Alene River Basin sediments

    USGS Publications Warehouse

    Beyer, W.N.; Audet, D.J.; Morton, Alexandra; Campbell, J.K.; LeCaptain, L.

    1998-01-01

    Feces from tundra swans (Cygnus columbianus [Ord]), Canada geese (Branta canadensis [L.]) and mallards (Anas platyrhynchos [L.]) were collected from the Coeur d?Alene River Basin and two reference areas to estimate exposure to lead from mining activities and to relate that exposure to the ingestion of contaminated sediments. The average acid-insoluble ash content of the feces, a measure of sediment, was 18% for Canada geese and tundra swans, and 12% for ducks. The 18% value corresponded to an estimated 9% sediment ingestion rate (dry weight). The 90th percentile for acid-insoluble ash in feces of tundra swans corresponds to an estimated 22% sediment in the diet. The average lead concentration (dry weight) of tundra swan feces from all Coeur d?Alene River Basin wetlands sampled was 880 mg/kg, compared to 2.1 mg kg1 from reference wetlands. The 90th percentile of lead in tundra swan feces from the Coeur d?Alene River Basin sites was 2700 mg kg1. Fecal lead concentrations of tundra swans from Harrison Slough, the wetland studied in most detail, were correlated (Spearman?s rho = 0.74, p < 0.05) with the acid-insoluble ash content of the feces. The very low lead concentrations in feces having low acid-insoluble ash contents established that the sediment was the primary source of the lead ingested by waterfowl. Sediment lead concentrations at 11 wetland sites were closely correlated (r = 0.91, p < 0.05) with average fecal lead concentrations for all waterfowl, corrected for the average percent acid-insoluble ash in the feces. The regression equation describing this relation, along with estimates of sediment ingestion, provides a straight-forward means of estimating the current exposure of waterfowl to lead and of predicting the potential exposure of waterfowl to lead under plans to clean up the contaminated sites.

  5. Environmental exposure to lead and mercury in Mexican children: a real health problem.

    PubMed

    Acosta-Saavedra, Leonor C; Moreno, Ma Elena; Rodríguez-Kessler, Theresia; Luna, Ana; Arias-Salvatierra, Daniela; Gómez, Rocío; Calderon-Aranda, Emma S

    2011-11-01

    Exposure to lead (Pb) and mercury (Hg) remains a world public health problem, particularly for young children in developing countries. In Mexico, the main sources of exposure to Pb and Hg are wastes from human activities that increase the natural sources of these metals. Pb and Hg are highly toxic during development and maturation periods of the central nervous system (CNS); these effects are associated with the risk for neurodegenerative diseases. Mexico has numerous exposure sources to Pb and Hg; nevertheless, information on exposure in children is limited, particularly for Hg. Therefore, we conducted a review of the studies performed in children exposed to Pb and Hg. Data presented support that an important proportion of Mexican children have Pb levels above values associated with dangerous effects. On the other hand, studies on Hg-exposure are scarce, so we need more studies to estimate the magnitude of the problem and to determine exposure levels in Mexican children. Available data support the urgent need for coordinated actions among researchers, and health and environmental government authorities to implement education and nutritional campaigns, as well as to decrease exposure and effects of Pb and Hg. In addition, there must be a priority for the implementation of educational campaigns directed to the general population, but with emphasis in parents, education staff and health care providers to decrease both the risk of exposure of children to Pb and Hg and the effects of the exposure to these metals.

  6. Suitability of a biochemical method for assessing the exposure of feral fish to lead

    SciTech Connect

    Hodson, P.V.; Blunt, B.R.; Whittle, M.

    1981-10-01

    A variety of biochemical techniques have been used to assessthe response of fish to contaminants. These techniques may provide valuable tools for determining the degree of impact on real fish populations of contaminant exposure and for identifying areas of contamination. Many of these techniques have not proven useful because they were not sensible, sensitive, or specific. This paper reviews the use of erythrocyte delta-amino levulinic acid dehydratase (ALAD) activity to indicate lead exposure of fish, both in the laboratory and in field surveys of Great Lakes fish. The enzyme has proven to bea reliable tool in laboratory studies of lead effects on rainbow trout (Salmo gairdneri). The field survey demonstrated that ALAD activity is a suitable indicator of lead exposure of lake trout (Salvelinus namaycush) but that more research is required to confirm its applicability to other species.

  7. [Assessment for effect of low level lead-exposure on neurobehavior in workers of printing house].

    PubMed

    Niu, Q; Dai, F; Chen, Y

    1998-11-30

    WHO Neurobehavioral Core Test Battery (NCTB) was conducted among 28 lead-exposed workers (mean age 24.84, SD2.85) in printing house and 46 controls (mean age 22.78, SD1.45), in order to assess whether low level lead exposure may be related to neurobehavioral dysfunction. The items of test were: 1. Profile of mood state(POMS), (2) Simple reaction time, (3) Digit span, (4) Santa Anna manual dexterity, (5) Digit simbol, (6) Benton visual retention; and Prusuit aiming test. In all the NCTB test values, there was no significant difference between two groups. Multiple stepwise regression analysis shows that exposure duration is related to neurobehavior scores. Mild lead exposure may affect neurobehavior in some degree but not significant.

  8. Biophysical Modelling to Simulate the Response to Multisite Left Ventricular Stimulation using a Quadripolar Pacing Lead

    PubMed Central

    Niederer, SA; Shetty, AK; Plank, G; Bostock, J; Razavi, R; Smith, NP; Rinaldi, CA

    2016-01-01

    Background Response to Cardiac Resynchronisation Therapy (CRT) is reduced in patients with postero-lateral scar. Multipolar pacing leads offer the ability to select desirable pacing sites and/or stimulate from multiple pacing sites concurrently using a single lead position. Despite this potential, the clinical evaluation and identification of metrics for optimisation of multisite CRT (MCRT) has not been performed. Methods The efficacy of MCRT via a quadripolar lead with two LV pacing sites in conjunction with RV pacing was compared with single site LV pacing using a coupled electro-mechanical biophysical model of the human heart with no, mild or severe scar in the LV postero-lateral wall. Result The maximum dP/dtmax improvement from baseline was 21%, 23%, 21% for standard CRT vs 22%, 24%, 25% for MCRT for no, mild and severe scar, respectively. In the presence of severe scar there was an incremental benefit of multisite vs standard CRT (25% vs 21%, 19% relative improvement). Minimizing total activation time (analogous to QRS duration) or minimizing the activation time of short axis slices of the heart did not correlate with CRT response. The peak electrical activation wave area in the LV corresponded with CRT response with an R2 value between 0.42-0.75. Conclusion Biophysical modelling predicts that in the presence of postero-lateral scar MCRT offers an improved response over conventional CRT. Maximising the activation wave area in the LV had the most consistent correlation with CRT response, independent of pacing protocol, scar size or lead location. PMID:22040178

  9. Lead, Arsenic, and Manganese Metal Mixture Exposures: Focus on Biomarkers of Effect.

    PubMed

    Andrade, V M; Mateus, M L; Batoréu, M C; Aschner, M; Marreilha dos Santos, A P

    2015-07-01

    The increasing exposure of human populations to excessive levels of metals continues to represent a matter of public health concern. Several biomarkers have been studied and proposed for the detection of adverse health effects induced by lead (Pb), arsenic (As), and manganese (Mn); however, these studies have relied on exposures to each single metal, which fails to replicate real-life exposure scenarios. These three metals are commonly detected in different environmental, occupational, and food contexts and they share common neurotoxic effects, which are progressive and once clinically apparent may be irreversible. Thus, chronic exposure to low levels of a mixture of these metals may represent an additive risk of toxicity. Building upon their shared mechanisms of toxicity, such as oxidative stress, interference with neurotransmitters, and effects on the hematopoietic system, we address putative biomarkers, which may assist in assessing the onset of neurological diseases associated with exposure to this metal mixture.

  10. Lead, arsenic and manganese metal mixture exposures: focus on biomarkers of effect

    PubMed Central

    Andrade, VL; Mateus, ML; Batoréu, MC; Aschner, M; Marreilha dos Santos, AP

    2015-01-01

    Summary The increasing exposure of human populations to excessive levels of metals continues to represent a matter of public health concern. Several biomarkers have been studied and proposed for the detection of adverse health effects induced by lead (Pb), arsenic (As) and manganese (Mn); however, these studies have relied on exposures to each single metal, which fails to replicate real-life exposure scenarios. These 3 metals are commonly detected in different environmental, occupational and food contexts and they share common neurotoxic effects, which are progressive and once clinically apparent may be irreversible. Thus, chronic exposure to low levels of a mixture of these metals represents an additive risk of toxicity. Building upon their shared mechanisms of toxicity, such as oxidative stress, interference with neurotransmitters and effects on hematopoietic system, we address putative biomarkers, which may be assist in assessing onset of neurological diseases associated with exposure to this metal mixture. PMID:25693681

  11. Prenatal exposure to lead in Spain: cord blood levels and associated factors.

    PubMed

    Llop, Sabrina; Aguinagalde, Xabier; Vioque, Jesus; Ibarluzea, Jesús; Guxens, Mònica; Casas, Maribel; Murcia, Mario; Ruiz, María; Amurrio, Ascensión; Rebagliato, Marisa; Marina, Loreto Santa; Fernandez-Somoano, Ana; Tardon, Adonina; Ballester, Ferran

    2011-05-01

    Lead is a known neurotoxic. Fetuses and infants are very vulnerable to lead exposure, since their blood-brain barrier is not completely formed. Hence, there is an importance for monitoring of blood lead levels prenatally and during early infancy. The aim of this study is to evaluate the prenatal exposure to lead and its association with maternal factors in four population based mother-child cohorts in Spain. The present research was carried out within the framework of the INMA project INfancia y Medio Ambiente (Environment and Childhood). A total of 1462 pregnant women were recruited between 2004 and 2008. Lead was analyzed in a sample of cord blood by thermal decomposition, amalgation, and Atomic Absorption Spectrometry. Maternal sociodemographic, lifestyle and dietary factors were obtained by questionnaires during pregnancy. A multivariate logistic regression model was constructed. The dependent variable was a dichotomous lead level variable (detected vs no detected, i.e. ≥ vs < 2μg/dL). A low percentage of cord blood samples with lead levels ≥ 2μg/dL were found (5.9%). Geometric mean and maximum were 1.06μg/dL and 19μg/dL, respectively. Smoking at the beginning of pregnancy, age, social class, weight gain during pregnancy, gravidity, and place of residence were the maternal factors associated with detectable cord blood lead levels. Mother's diet does not appear to be a determining factor of lead exposure. Nevertheless, daily intake of iron and zinc may act as a protective factor against having cord blood lead levels ≥ 2μg/dL. In the different regions of Spain taking part in this study, lead levels to which newborns are exposed are low. Mobilization of lead from bones may be the main contributor to the cord blood levels. Copyright © 2011 Elsevier B.V. All rights reserved.

  12. Preimplantation Exposure to Bisphenol A and Triclosan May Lead to Implantation Failure in Humans

    PubMed Central

    Yuan, Mu; Bai, Ming-Zhu; Huang, Xu-Feng; Zhang, Yue; Liu, Jing; Hu, Min-Hao; Zheng, Wei-Qian; Jin, Fan

    2015-01-01

    Endocrine disrupting chemicals (EDCs) are chemicals that have the capacity to interfere with normal endocrine systems. Two EDCs, bisphenol A (BPA) and triclosan (TCS), are mass-produced and widespread. They both have estrogenic properties and similar chemical structures and pharmacokinetic features and have been detected in human fluids and tissues. Clinical evidence has suggested a positive association between BPA exposure and implantation failure in IVF patients. Studies in mouse models have suggested that preimplantation exposure to BPA and TCS can lead to implantation failure. This paper reviews the relationship between preimplantation exposure to BPA and TCS and implantation failure and discusses the remaining problems and possible solutions. PMID:26357649

  13. Shaped, lead-loaded acrylic filters for patient exposure reduction and image-quality improvement

    SciTech Connect

    Gray, J.E.; Stears, J.G.; Frank, E.D.

    1983-03-01

    Shaped filters that are constructed of lead-loaded acrylic material for use in patient radiography are discussed. Use of the filters will result in improved overall image quality with significant exposure reduction to the patient (approximately a 2X reduction in breast exposure and a 3X reduction in thyroid gland exposure). Detailed drawings of the shaped filters for scoliosis radiography, cervical spine radiography, and for long film changers in special procedures are provided. The use of the scoliosis filters is detailed and includes phantom and patient radiographs and dose reduction information.

  14. Human lead exposure in England from approximately 5500 BP to the 16th century AD.

    PubMed

    Budd, P; Montgomery, J; Evans, J; Trickett, M

    2004-01-05

    Lead concentration and isotope ratio data are presented for the tooth enamel of 77 individuals buried in England and spanning approximately 5000 years from the Neolithic until the 16th century AD. Whereas other tissues may be affected by diagenesis in the burial environment, the Pb concentration of tooth enamel is directly related to childhood exposure. This record is preserved post-mortem and over archaeological time. Tooth enamel Pb concentrations in the prehistoric period appear to be variable within the range 0.04 to approximately 0.4 ppm, with occasional higher levels. The Romano-British and medieval periods show a marked increase in Pb exposures with enamel concentrations reaching up to approximately 40 ppm. These exposures would today be associated with industrial pollution. Exposures appear to be highly variable compared with modern people, however, with many medieval individuals having very low enamel Pb concentrations comparable with prehistoric people. Lead isotope data refine this picture. We distinguish between the diverse isotopic ratios we believe to be characteristic of 'natural' exposure to Pb-from geological sources via the diet-and the much narrower isotopic range characteristic of exposure to technological Pb from ore sources. Taken together the data suggest that the maximum concentrations associated with 'non-technological' exposure at any period are approximately 0.5-1.0 ppm, similar to that reported for modern people in England.

  15. The astonishingly holistic role of urban soil in the exposure of children to lead.

    NASA Astrophysics Data System (ADS)

    Mielke, Howard; Gonzales, Christopher; Powell, Eric

    2017-04-01

    The long-term resilience and sustainability of urban communities is associated with its environmental quality. One major impediment to community welfare is children's exposure to lead because it is a root cause of disparity and chronic conditions including health, learning, and behavioral differences. There is no safe level of lead exposure and this revelation is confounded by the lack of an effective intervention after exposure takes place. In August, 2005, Hurricane Katrina flooded 80% of New Orleans. This report explores the natural experiment of the dynamic changes of soil and children's blood lead in New Orleans before and ten years after the flood. Matched pre- and post-Hurricane soil lead and children's blood lead results were stratified by 172 communities of New Orleans. GIS methods were used to organize, describe, and map the pre- and post-Katrina data. Comparing pre- and post-Katrina results, simultaneous decreases occurred in soil lead and children's blood lead response. Health and welfare disparities continue to exist between environments and children's exposure living in interior compared with outer communities of the city. At the scale of a city this investigation demonstrates that declining soil lead effectively reduces children's blood lead. The astonishingly holistic role of soil relates to its position as a lead dust deposition reservoir and, at the same time, as an open source of ingestible and inhalable lead dust. Decreasing the soil lead on play areas of urban communities is beneficial and economical as a method for effective lead intervention and primary prevention. References Mielke, H.W.; Gonzales, C.R.; Powell, E.T.; Mielke, P.W. Jr. Spatiotemporal dynamic transformations of soil lead and children's blood lead ten years after Hurricane Katrina: New grounds for primary prevention. Environ. Int. 2016, DOI: 10.1016/j.envint.2016.06.017. Mielke, H.W.; Gonzales, C.R.; Powell, E.T. In review. The dynamic lead exposome and children's health in New

  16. Hazard of lead exposure in the home from recycled automobile storage batteries.

    PubMed

    Dolcourt, J L; Finch, C; Coleman, G D; Klimas, A J; Milar, C R

    1981-08-01

    Two families from rural areas of North Carolina had excessive lead exposure which resulted from either recycling exhausted automobile storage batteries in the home or burning the discarded battery casings for home heating. One child developed encephalopathy resulting in permanent brain damage. Decontamination efforts reduced the quantity of lead in the home environment by greater than 50%. Rural children, previously considered to be at low risk, may in fact receive profound exposures which may go unrecognized until encephalopathy occurs. Occupational histories should be obtained from parents in order to detect children at risk from environmental toxins brought into the home on workmen's bodies and clothing.

  17. Hazard of lead exposure in the home from recycled automobile storage batteries

    SciTech Connect

    Dolcourt, J.L.; Finch, C.; Coleman, G.D.; Klimas, A.J.; Milar, C.R.

    1981-08-01

    Two families from rural areas of North Carolina had excessive lead exposure which resulted from either recycling exhausted automobile storage batteries in the home or burning the discarded battery casings for home heating. One child developed encephalopathy resulting in permanent brain damage. Decontamination efforts reduced the quantity of lead in the home environment by greater than 50%. Rural children, previously considered to be at low risk, may in fact receive profound exposures which may go unrecognized until encephalopathy occurs. Occupational histories should be obtained from parents in order to detect children at risk from environmental toxins brought into the home on workmen's bodies and clothing.

  18. Developmental Lead Exposure Alters Synaptogenesis through Inhibiting Canonical Wnt Pathway In Vivo and In Vitro

    PubMed Central

    Hu, Fan; Xu, Li; Liu, Zhi-Hua; Ge, Meng-Meng; Ruan, Di-Yun; Wang, Hui-Li

    2014-01-01

    Lead (Pb) exposure has been implicated in the impairment of synaptic plasticity in the developing hippocampus, but the mechanism remains unclear. Here, we investigated whether developmental lead exposure affects the dendritic spine formation through Wnt signaling pathway in vivo and in vitro. Sprague–Dawley rats were exposed to lead throughout the lactation period and Golgi-Cox staining method was used to examine the spine density of pyramidal neurons in the hippocampal CA1 area of rats. We found that lead exposure significantly decreased the spine density in both 14 and 21 days-old pups, accompanied by a significant age-dependent decline of the Wnt7a expression and stability of its downstream protein (β-catenin). Furthermore, in cultured hippocampal neurons, lead (0.1 and 1 µM lead acetate) significantly decreased the spine density in a dose-dependent manner. Exogenous Wnt7a application attenuated the decrease of spine density and increased the stability of the downstream molecules in Wnt signaling pathway. Together, our results suggest that lead has a negative impact on spine outgrowth in the developing hippocampus through altering the canonical Wnt pathway. PMID:24999626

  19. Exposure of Spectacled Eiders and other diving ducks to lead in western Alaska

    USGS Publications Warehouse

    Flint, Paul L.; Petersen, Margaret R.; Grand, James B.

    1997-01-01

    Lead poisoning, resulting from ingestion of spent shot, has been identified as a cause of mortality in Spectacled Eiders (Somateria fischeri) on the Yukon–Kuskokwim Delta, Alaska. We examined lead-exposure rates of adult and juvenile Spectacled Eiders and other diving ducks, using atomic absorption spectrophotometry of blood samples. Additionally, we X-rayed birds in the field to identify ingested shot. We detected shot in the gizzards of 11.6% of Spectacled Eiders X-rayed. During the period from arrival through incubation, 13.0% of adult females and 6.6% of adult males had elevated blood lead levels when captured. During the brood-rearing period, 35.8% of adult females and 12.2% of ducklings were exposed to lead when captured. There was an increase in the probability of exposure of adult females with date sampled. We predict that 50% of the successfully breeding hens were likely exposed to lead, and 25–37% of the Spectacled Eider breeding population was exposed to lead. The long-term effects of sublethal doses on Spectacled Eiders are unknown; however, exposure of nesting females and young birds to lead may result in reduced over-winter survival and (or) reduced fecundity.

  20. Effects of chronic low level lead exposure on the physiology of individually identifiable neurons.

    PubMed

    Audesirk, G; Audesirk, T

    1983-01-01

    Although chronic exposure to lead has been correlated with a variety of behavioral and neurochemical deficits in humans and other mammals, little is known of the mechanisms of action of chronic lead at the level of the individual nerve cell. We have used the individually identifiable neurons of the freshwater pond snail Lymnaea stagnalis as a model system to investigate the effects of chronic low level (5 microM) lead exposure on neuronal physiology. Thirteen neuronal parameters were measured with intracellular microelectrode recording in each of six different identifiable neurons or homogeneous neuron clusters. Results were analyzed by a multivariate analysis of variance (MANOVA). MANOVA analysis indicates that there is a significant overall effect of lead exposure (p = 0.0001) and a significant interaction between lead and neuron type (p = 0.01). In most neuron types, chronic lead causes an increase in the resting potential, a slowing of recovery of the membrane potential after the undershoot of a spike, a decrease in spontaneous spiking activity, and a decrease in the input resistance. Lead also has differential effects on identifiable neurons, depressing excitability in some neuron types while not altering excitability in others.

  1. The analysis of QT interval and repolarization morphology of the heart in chronic exposure to lead.

    PubMed

    Kiełtucki, J; Dobrakowski, M; Pawlas, N; Średniawa, B; Boroń, M; Kasperczyk, S

    2017-10-01

    There are no common recommendations regarding electrocardiographic monitoring in occupationally exposed workers. Therefore, the present study was designed to investigate whether exposure to lead results in an increase of selected electrocardiography (ECG) pathologies, such as QT interval prolongation and repolarization disorders, in occupationally exposed workers. The study group included 180 workers occupationally exposed to lead compounds. The exposed group was divided according to the median of the mean blood lead level (PbBmean) calculated based on a series of measurements performed during 5-year observation period (35 µg/dl) into two subgroups: low exposure (LE, PbBmean = 20.0-35.0 µg/dl) and high exposure (HE, PbBmean = 35.1-46.4 µg/dl). The control group consisted of 69 healthy workers without occupational exposure to lead. ECG evaluation included the analysis of heart rate (HR), QT interval and repolarization abnormalities. Mean QT interval was significantly greater in the exposed population than in the control group by 2%. In the HE group, mean QT interval was significantly greater than in the control group by 4% and significantly different from those noted in the LE group. Positive correlations between QT interval and lead exposure indices were also reported. Besides, there was a negative correlation between HR and blood lead level. Increased concentration of lead in the blood above 35 μg/dl is associated with the QT interval prolongation, which may trigger arrhythmias when combined with other abnormalities, such as long QT syndrome. Therefore, electrocardiographic evaluation should be a part of a routine monitoring of occupationally exposed populations.

  2. Characterizing Golden Eagle risk to lead and anticoagulant rodenticide exposure: A review

    USGS Publications Warehouse

    Herring, Garth; Eagles-Smith, Collin A.; Buck, Jeremy A.

    2017-01-01

    Contaminant exposure is among the many threats to Golden Eagle (Aquila chrysaetos) populations throughout North America, particularly lead poisoning and anticoagulant rodenticides (AR). These threats may act in concert with others (e.g., lead poisoning and trauma associated with striking objects) to exacerbate risk. Golden Eagles are skilled hunters but also exploit scavenging opportunities, making them particularly susceptible to contaminant exposure from ingesting tissues of poisoned or shot animals. Lead poisoning has long been recognized as an important source of mortality for Golden Eagles throughout North America. More recently, ARs have been associated with both sublethal and lethal effects in raptor species worldwide. In this review, we examine the current state of knowledge for lead and AR exposure in Golden Eagles, drawing from the broader raptor contaminant ecology literature. We examine lead and AR sources within Golden Eagle habitats, exposure routes and toxicity, effects on individuals and populations, synergistic effects, and data and information needs. Continued research addressing data needs and information gaps will help with Golden Eagle conservation planning.

  3. Effects of lead exposure on dendrite and spine development in hippocampal dentate gyrus areas of rats.

    PubMed

    Hu, Fan; Ge, Meng-Meng; Chen, Wei-Heng

    2016-03-01

    Lead exposure has been implicated in the impairment of synaptic plasticity in the hippocampal dentate gyrus (DG) areas of rats. However, whether the degradation of physiological properties is based on the morphological alteration of granule neurons in DG areas remains elusive. Here, we examined the dendritic branch extension and spine formation of granule neurons after lead exposure during development in rats. Dendritic morphology was studied using Golgi-Cox stain method, which was followed by Sholl analysis at postnatal days 14 and 21. Our results indicated that, for both ages, lead exposure significantly decreased the total dendritic length and spine density of granule neurons in the DG of the rat hippocampus. Further branch order analysis revealed that the decrease of dendritic length was observed only at the second branch order. Moreover, there were obvious deficits in the proportion and size of mushroom-type spines. These deficits in spine formation and maturity were accompanied by a decrease in Arc/Arg3.1 expression. Our present findings are the first to show that developmental lead exposure disturbs branch and spine formation in hippocampal DG areas. Arc/Arg3.1 may have a critical role in the disruption of neuronal morphology and synaptic plasticity in lead-exposed rats.

  4. Occupational and environmental exposure to lead and Paget's disease of bone

    SciTech Connect

    Spencer, H.; Sontag, S.J. )

    1994-01-01

    This paper reports an association between lead exposure and Paget's disease of bone. Detailed interviews of occupational or environmental exposure to lead established this association in 44 of 48 male patients, i.e., in 92% of the total number of patients or in all patients who were interviewed. Life-long occupational and environmental histories were also obtained from two other categories of patients with Paget's disease: From a small number of females with this disease and from affected relatives of patients with Paget's disease. Paget's disease in family members has been reported by others to be linked to genetic factors. The histories of the small number of these two categories of patients with Paget's disease; the females and the family members, revealed occupational or environmental exposure to a toxic substance, primarily to lead, in the past. This presentation also hypothesizes that lead-exposure is the basis for hyperparathyroidism, which coexists in patients with Paget's disease of bone. It also deals with the attempted correlation of lead contamination in different areas and the prevalence of Paget's disease. 83 refs., 1 fig., 1 tab.

  5. [The activation of microglia caused by lead and manganese co-exposure induces activation of astrocytes and decrease of glutamine synthetase activity].

    PubMed

    Guan, Ruili; Wang, Tao; Chen, Jingyuan; Luo, Wenjing; Liu, Mingchao

    2016-03-01

    To establish microglia and astrocyte co-culture cell model and investigate the effects of lead and manganese alone or co-exposure on different glia cells and the effect of microglia activation on astrocytes' function. MTT assay was performed to select the appropriate dose and time of lead and manganese exposure that didn't affect C6 cell growth. Then with BV2 microglia and C6 astrocytes, cell models were established through lead acetate and manganese chloride alone and co-exposure. The cell models were further divided into three types: direct stimulation, conditioned medium and co-culture. In the direct stimulation method, C6 cells were directly treated with complete medium or complete medium containing lead acetate and/or manganese chloride for 24 hours. In conditioned medium method, BV2 cells were cultured in the complete medium or complete medium containing lead acetate and/or manganese chloride for 24 hours, and then the supernatants were centrifuged and used to treat C6 cells for another 24 hours. In co-culture method, BV2 cells were seeded in semipermeable membrane inserts and the inserts were put in a normal 12-well plate; C6 cells were seeded in another 12-well plate; complete medium or complete medium containing lead acetate and/or manganese chloride was added in the wells to culture BV2 cells for 24 hours; the culture medium was abandoned, the cells seeded in the inserts were gently rinsed with complete medium and then the inserts were put into the 12-well plate where C6 were seeded before; the BV2 cells and C6 cells were co-cultured for another 24 hours. The effects of lead and manganese alone or co-exposure on different glia cells were analyzed through CR3/CD11b/OX42 and glial fibrillary acidic protein (GFAP) expression detection by Western blotting; the effect of microglia activation on astrocyte glutamate-glutamine cycle loop was studied through glutamine synthetase (GS) level detected by Western blotting. In direct stimulation method, 10 μmol/L lead

  6. Corrosion of glassy carbon neural electrodes under electrical stimulation and chemical exposure

    NASA Astrophysics Data System (ADS)

    Gong, Nick Thomas

    Advances in research of neural prosthetics have led to the development of novel materials used for neural stimulation applications. Glassy carbon (GC) has demonstrated promise as a novel and robust material that can be used in such applications. This study focused on reporting the in-vitro testing of GC microelectrodes under stimulation and chemical exposure to simulate an in-vivo environment, and to determine corrosion. Microelectrode arrays were fabricated and tested for an electrochemical (EC) setup for long-term corrosion tests. GC electrode pillars were used to test the testing apparatus, and confirm its ability to stimulate the GC microelectrodes. Electrode stimulation was conducted over 7 and 14 day time periods in phosphate buffer saline (PBS) with two different types of hydrogen peroxide (H2O2), USP and ACS. Corrosion of GC neural microelectrode arrays was monitored by physical, chemical, and electrochemical characterization methods. GC corrosion was characterized and evaluated over the duration of this study. Both GC and platinum microelectrode arrays were subjected to the same parameters. USP H2O2 did not corrode GC electrodes and characterization revealed that a protective layer can be preventing further electrode degradation. ACS H2O2 corroded GC electrodes. Implications of this work have given insights and new directions on testing neural prosthetic microelectrode arrays for stimulation applications.

  7. National Human Exposure Assessment Survey: analysis of exposure pathways and routes for arsenic and lead in EPA Region 5.

    PubMed

    Clayton, C A; Pellizzari, E D; Quackenboss, J J

    2002-01-01

    The National Human Exposure Assessment Survey (NHEXAS) Phase I field study conducted in EPA Region 5 (Great Lakes Area) provides extensive exposure data on a representative sample of approximately 250 residents of the region. Associated environmental media and biomarker (blood, urine) concentration data were also obtained for the study participants to aid in understanding of the relationships of exposures to both contaminant pathways and doses. Besides fulfilling the primary NHEXAS objectives, the NHEXAS data provided an opportunity to explore secondary usages, such as examining pathway to route of exposure relationships. A generic type of structural equation model was used to define the anticipated relationships among the various data types for both arsenic (As) and lead (Pb). Since, by design, only a few participants provided data for all sample types, implementing this model required that some media concentrations (outdoor air and soil) be imputed for subjects with missing information by using measurements collected in the same geographic area and time period. The model, and associated pairwise correlations, generally revealed significant but weak associations among the concentrations, exposures, and doses; the strongest associations occurred for the various air measurements (indoor versus outdoor and personal). The generally weak associations were thought to be partly due to the absence of complete coverage of nonresidential environmental media and to nonsynchronization of relevant measurement times and integration periods of collection across the various sample types. In general, relationships between the NHEXAS questionnaire data and the various concentration, exposure, and body-burden measures were also weak. The model results and the modeling exercise suggest several ways for optimizing the design of future exposure assessment studies that are aimed at supporting structural modeling activities.

  8. Lead exposure in passerines inhabiting lead-contaminated floodplains in the Coeur d'Alene River Basin, Idaho, USA

    USGS Publications Warehouse

    Johnson, G.D.; Audet, D.J.; Kern, John W.; LeCaptain, L.J.; Strickland, M.D.; Hoffman, D.J.; McDonald, L.L.

    1999-01-01

    Blood collected from song sparrows (Melospiza melodia) and American robins (Turdus migratorius) captured with mist nets in a lead-contaminated (assessment) area and nearby uncontaminated (reference) areas within the Coeur d'Alene Basin in northern Idaho was analyzed for d-aminolevulinic acid dehydratase activity (ALAD) and hematocrit levels, and livers were analyzed for lead. Mean ALAD inhibition in the assessment area was 51% in song sparrows and 75% in American robins. The proportion of the sampled population with ALAD inhibition >50% was calculated to be 43% for song sparrows and 83% for American robins. Assessment area hematocrit values for song sparrows (0 = 39.9) and American robins (0 = 39.5) were lower than in reference areas (0 = 42.4 for song sparrows and 40.2 for American robins); however, differences were not statistically significant (p > 0.05). Significantly higher levels of lead (wet weight) were found in livers from song sparrows captured on the assessment area (0 = 1.93 ppm) than on reference areas (0 = 0.10 ppm) (p = 0.0079). Study results indicate that 43% (95% confidence interval [CI] = 12.9-77.5%) of the song sparrows and 83% (95% CI = 41.8-99.2%) of the American robins inhabiting the floodplain along the Coeur d'Alene River in the assessment area are being exposed to lead at levels sufficient to inhibit ALAD by > 50%. Variability in lead exposure indicators was attributed to high variability in environmental lead concentrations in the Coeur d'Alene River Basin.

  9. Effects of lead exposure on hippocampal metabotropic glutamate receptor subtype 3 and 7 in developmental rats

    PubMed Central

    Xu, Jian; Yan, Huai C; Yang, Bo; Tong, Lu S; Zou, Yu X; Tian, Ying

    2009-01-01

    Background A complete explanation of the mechanisms by which Pb2+ exerts toxic effects on developmental central nervous system remains unknown. Glutamate is critical to the developing brain through various subtypes of ionotropic or metabotropic glutamate receptors (mGluRs). Ionotropic N-methyl-D-aspartate receptors have been considered as a principal target in lead-induced neurotoxicity. The relationship between mGluR3/mGluR7 and synaptic plasticity had been verified by many recent studies. The present study aimed to examine the role of mGluR3/mGluR7 in lead-induced neurotoxicity. Methods Twenty-four adult and female rats were randomly selected and placed on control or 0.2% lead acetate during gestation and lactation. Blood lead and hippocampal lead levels of pups were analyzed at weaning to evaluate the actual lead content at the end of the exposure. Impairments of short -term memory and long-term memory of pups were assessed by tests using Morris water maze and by detection of hippocampal ultrastructural alterations on electron microscopy. The impact of lead exposure on mGluR3 and mGluR7 mRNA expression in hippocampal tissue of pups were investigated by quantitative real-time polymerase chain reaction and its potential role in lead neurotoxicity were discussed. Results Lead levels of blood and hippocampi in the lead-exposed rats were significantly higher than those in the controls (P < 0.001). In tests using Morris Water Maze, the overall decrease in goal latency and swimming distance was taken to indicate that controls had shorter latencies and distance than lead-exposed rats (P = 0.001 and P < 0.001 by repeated-measures analysis of variance). On transmission electron microscopy neuronal ultrastructural alterations were observed and the results of real-time polymerase chain reaction showed that exposure to 0.2% lead acetate did not substantially change gene expression of mGluR3 and mGluR7 mRNA compared with controls. Conclusion Exposure to lead before and after

  10. Occupational exposure to manganese, copper, lead, iron, mercury and zinc and the risk of Parkinson's disease.

    PubMed

    Gorell, J M; Johnson, C C; Rybicki, B A; Peterson, E L; Kortsha, G X; Brown, G G; Richardson, R J

    1999-01-01

    A population-based case-control study was conducted in the Henry Ford Health System (HFHS) in metropolitan Detroit to assess occupational exposures to manganese, copper, lead, iron, mercury and zinc as risk factors for Parkinson's disease (PD). Non-demented men and women 50 years of age who were receiving primary medical care at HFHS were recruited, and concurrently enrolled cases (n = 144) and controls (n = 464) were frequency-matched for sex, race and age (+/- 5 years). A risk factor questionnaire, administered by trained interviewers, inquired about every job held by each subject for 6 months from age 18 onward, including a detailed assessment of actual job tasks, tools and environment. An experienced industrial hygienist, blinded to subjects' case-control status, used these data to rate every job as exposed or not exposed to one or more of the metals of interest. Adjusting for sex, race, age and smoking status, 20 years of occupational exposure to any metal was not associated with PD. However, more than 20 years exposure to manganese (Odds Ratio [OR] = 10.61, 95% Confidence Interval [CI] = 1.06, 105.83) or copper (OR = 2.49, 95% CI = 1.06,5.89) was associated with PD. Occupational exposure for > 20 years to combinations of lead-copper (OR = 5.24, 95% CI = 1.59, 17.21), lead-iron (OR = 2.83, 95% CI = 1.07,7.50), and iron-copper (OR = 3.69, 95% CI = 1.40,9.71) was also associated with the disease. No association of occupational exposure to iron, mercury or zinc with PD was found. A lack of statistical power precluded analyses of metal combinations for those with a low prevalence of exposure (i.e., manganese, mercury and zinc). Our findings suggest that chronic occupational exposure to manganese or copper, individually, or to dual combinations of lead, iron and copper, is associated with PD.

  11. Mortality and lead exposure: a retrospective cohort study of Swedish smelter workers.

    PubMed Central

    Gerhardsson, L; Lundström, N G; Nordberg, G; Wall, S

    1986-01-01

    The study is based on the work histories and mortality data for 3832 male workers first employed before 1967 at a copper smelter in northern Sweden and followed up from 1950 to 1981. From the 3832 workers a lead cohort consisting of 437 workers employed for at least three years at sites with considerable lead exposure during 1950-74 was selected. These workers had regularly had blood lead measurements performed since 1950. Based on the cumulative blood lead dose 1950-74 and peak blood lead values, the cohort was subdivided into high mean, low mean, high peak, and low peak groups. Standardised mortality ratios (SMR) were calculated for the six groups using general and local reference populations. The original cohort of 3832 workers showed considerable excess of deaths for total mortality, malignant neoplasms especially lung and stomach cancer, ischaemic heart diseases, and cerebrovascular diseases when compared with the general population. In the lead cohort where the workers had been subjected to a considerable lead exposure only the raised SMR for lung cancer was sustained (SMR = 162; not significant). No significant differences were found between high lead and low lead exposed smelter workers. PMID:3778840

  12. Evaluation of the hepatotoxic risk caused by lead acetate via skin exposure using a proteomic approach.

    PubMed

    Fang, Jia-You; Wang, Pei-Wen; Huang, Chun-Hsun; Hung, Yi-Yun; Pan, Tai-Long

    2014-11-01

    Lead compounds exhibit a high degree of cytotoxicity and carcinogenicity. We evaluated the impact of lead acetate on the liver by skin exposure as well as the changes in protein profiles reflecting pathogenic processes. Functional proteomic tools showed that the most meaningful protein changes were involved in protein folding, ER stress, and apoptosis in the presence of an organic lead compound. Treatment with lead acetate also elicits intracellular ROS levels as well as carbonyl modification of chaperone proteins, suggesting that lead might trigger the unfolded protein response due to oxidative stress. Lead application induced ER stress, as indicated by the promotion of GRP78 and by increased expression of the transcription factors ATF6, IRE1α, and PERK. Moreover, upregulation of GRP75 may participate in lead-caused hepatic cytotoxicity while abrogation of GRP75 appears to attenuate the inhibition of cell growth. Our findings demonstrate that accumulation of organic lead in the liver can induce oxidative imbalance and protein impairment that may result in ER stress followed by liver injuries. Hepatic proteome profiles delineate a finer picture of protein networks and metabolic pathways primarily involved in lead-initiated hepatic toxicity via skin exposure.

  13. Lead Paint Exposure Assessment in High Bays of Johnson Space Center

    NASA Technical Reports Server (NTRS)

    Stanch, Penney; Plaza, Angel; Keprta, Sean

    2008-01-01

    This slide presentation reviews the program to assess the possibility of lead paint exposure in the high bays of some of the Johnson Space Center buildings. Some of the buildings in the Manned Space Flight Center (MSC) were built in 1962 and predate any considerations to reduce lead in paints and coatings. There are many of these older buildings that contain open shops and work areas that have open ceilings, These shops include those that had operations that use leaded gasoline, batteries, and lead based paints. Test were planned to be conducted in three phases: (1) Surface Dust sampling, (2) personal exposure montioring, and (3) Ceiling paint Sampling. The results of the first two phases were reviewed. After considering the results of the first two phases, and the problems associated with the retrieval of samples from high ceilings, it was determined that the evaluation of ceiling coatings would be done on a project by project and in response to a complaint.

  14. Hemograms for and nutritional condition of migrant bald eagles tested for exposure to lead.

    PubMed

    Miller, M J; Wayland, M E; Bortolotti, G R

    2001-07-01

    Plasma proteins, hematocrit, differential blood counts were examined and nutritional condition was estimated for bald eagles (Haliaeetus leucocephalus) trapped (n = 6