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Sample records for current lead exposure

  1. Glazed clay pottery and lead exposure in Mexico: Current experimental evidence.

    Science.gov (United States)

    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.

  2. Lead toxicity: current concerns.

    OpenAIRE

    Goyer, R A

    1993-01-01

    Over the 20-year period since the first issue of Environmental Health Perspectives was published, there has been considerable progress in the understanding of the potential toxicity of exposure to lead. Many of these advances have been reviewed in published symposia, conferences, and review papers in EHP. This brief review identifies major advances as well as a number of current concerns that present opportunities for prevention and intervention strategies. The major scientific advance has be...

  3. Cryogenic current leads

    Energy Technology Data Exchange (ETDEWEB)

    Zizek, F.

    1982-01-01

    Theoretical, technical and design questions are examined of cryogenic current leads for SP of magnetic systems. Simplified mathematical models are presented for the current leads. To illustrate modeling, the calculation is made of the real current leads for 500 A and three variants of current leads for 1500 A for the enterprise ''Shkoda.''

  4. Exposure of Bacterial Biofilms to Electrical Current Leads to Cell Death Mediated in Part by Reactive Oxygen Species.

    Science.gov (United States)

    Brinkman, Cassandra L; Schmidt-Malan, Suzannah M; Karau, Melissa J; Greenwood-Quaintance, Kerryl; Hassett, Daniel J; Mandrekar, Jayawant N; Patel, Robin

    2016-01-01

    Bacterial biofilms may form on indwelling medical devices such as prosthetic joints, heart valves and catheters, causing challenging-to-treat infections. We have previously described the 'electricidal effect', in which bacterial biofilms are decreased following exposure to direct electrical current. Herein, we sought to determine if the decreased bacterial quantities are due to detachment of biofilms or cell death and to investigate the role that reactive oxygen species (ROS) play in the observed effect. Using confocal and electron microscopy and flow cytometry, we found that direct current (DC) leads to cell death and changes in the architecture of biofilms formed by Gram-positive and Gram-negative bacteria. Reactive oxygen species (ROS) appear to play a role in DC-associated cell death, as there was an increase in ROS-production by Staphylococcus aureus and Staphylococcus epidermidis biofilms following exposure to DC. An increase in the production of ROS response enzymes catalase and superoxide dismutase (SOD) was observed for S. aureus, S. epidermidis and Pseudomonas aeruginosa biofilms following exposure to DC. Additionally, biofilms were protected from cell death when supplemented with antioxidants and oxidant scavengers, including catalase, mannitol and Tempol. Knocking out SOD (sodAB) in P. aeruginosa led to an enhanced DC effect. Microarray analysis of P. aeruginosa PAO1 showed transcriptional changes in genes related to the stress response and cell death. In conclusion, the electricidal effect results in death of bacteria in biofilms, mediated, at least in part, by production of ROS.

  5. Magnesium Diboride Current Leads

    Science.gov (United States)

    Panek, John

    2010-01-01

    A recently discovered superconductor, magnesium diboride (MgB2), can be used to fabricate conducting leads used in cryogenic applications. Dis covered to be superconducting in 2001, MgB2 has the advantage of remaining superconducting at higher temperatures than the previously used material, NbTi. The purpose of these leads is to provide 2 A of electricity to motors located in a 1.3 K environment. The providing environment is a relatively warm 17 K. Requirements for these leads are to survive temperature fluctuations in the 5 K and 11 K heat sinks, and not conduct excessive heat into the 1.3 K environment. Test data showed that each lead in the assembly could conduct 5 A at 4 K, which, when scaled to 17 K, still provided more than the required 2 A. The lead assembly consists of 12 steelclad MgB2 wires, a tensioned Kevlar support, a thermal heat sink interface at 4 K, and base plates. The wires are soldered to heavy copper leads at the 17 K end, and to thin copper-clad NbTi leads at the 1.3 K end. The leads were designed, fabricated, and tested at the Forschungszentrum Karlsruhe - Institut foer Technische Physik before inclusion in Goddard's XRS (X-Ray Spectrometer) instrument onboard the Astro-E2 spacecraft. A key factor is that MgB2 remains superconducting up to 30 K, which means that it does not introduce joule heating as a resistive wire would. Because the required temperature ranges are 1.3-17 K, this provides a large margin of safety. Previous designs lost superconductivity at around 8 K. The disadvantage to MgB2 is that it is a brittle ceramic, and making thin wires from it is challenging. The solution was to encase the leads in thin steel tubes for strength. Previous designs were so brittle as to risk instrument survival. MgB2 leads can be used in any cryogenic application where small currents need to be conducted at below 30 K. Because previous designs would superconduct only at up to 8 K, this new design would be ideal for the 8-30 K range.

  6. Current leads for superconducting magnets

    International Nuclear Information System (INIS)

    Ishibashi, Kenji

    1989-01-01

    Current leads for superconducting magnets have been studied since 1960's. The technology of current leads may seem to have been established both in theory and experiment before the middle of 1970's. Nevertheless, a wide variety of superconducting magnets have been introduced in the last 15 years, and the demands for special current leads have increased in accordance to the variety. A steady advance has been made in the design theory and fabrication of current leads. This paper describes the recent current lead technology regarding the design theory, safety in accidents, and high current capability. (author)

  7. Neurophysiological effects of lead exposure

    Energy Technology Data Exchange (ETDEWEB)

    Rosen, I.; Wildt, K.; Gullberg, B.; Berlin, M.

    1983-10-01

    A series of neurophysiological variables was measured for men occupationally exposed to lead. The results were related to the degree of lead exposure and to the concentrations of lead and zinc protoporphyrin in blood. A small but significant correlation was observed between lead exposure and motor and sensory conduction velocities in the lower limbs, the conduction velocities of slow motor fibers in the upper limbs, and also sensory nerve action potentials. It is suggested that a neurophysiological examination should be considered in the surveillance of the health of lead workers.

  8. Current lead thermal analysis code 'CURRENT'

    International Nuclear Information System (INIS)

    Yamaguchi, Masahito; Tada, Eisuke; Shimamoto, Susumu; Hata, Kenichiro.

    1985-08-01

    Large gas-cooled current lead with the capacity more than 30 kA and 22 kV is required for superconducting toroidal and poloidal coils for fusion application. The current lead is used to carry electrical current from the power supply system at room temperature to the superconducting coil at 4 K. Accordingly, the thermal performance of the current lead is significantly important to determine the heat load requirements of the coil system at 4 K. Japan Atomic Energy Research Institute (JAERI) has being developed the large gas-cooled current leads with the optimum condition in which the heat load is around 1 W per 1 kA at 4 K. In order to design the current lead with the optimum thermal performances, JAERI developed thermal analysis code named as ''CURRENT'' which can theoretically calculate the optimum geometric shape and cooling conditions of the current lead. The basic equations and the instruction manual of the analysis code are described in this report. (author)

  9. Large-capacity current leads

    International Nuclear Information System (INIS)

    Ballarino, A.

    2008-01-01

    Feeding superconducting magnets with reliable low-loss devices is a key issue for any cryo-electrical system. Conventional or HTS current leads can be used, and cooling methods, materials, and geometries can be chosen to optimize the thermo-electrical performance of the system. The LHC magnets are powered via more than 3000 current leads transporting altogether about 3 MA of current. With thousands of leads, the LHC lead project represents today the largest project of its kind ever undertaken. Following a review of the LHC lead project, an overview of the choices that can be made for the optimization of large capacity current leads is presented. Examples are given of other leads for large scale magnet systems for which the use of HTS is being envisaged

  10. Neurobehavioural effects of occupational exposure to lead.

    Science.gov (United States)

    Williamson, A M; Teo, R K

    1986-06-01

    A set of neurobehavioural tests selected on the basis of information processing theory was used to study the effect of low level occupational lead exposure on 59 lead workers compared with a matched control group of the same number. Only one of the lead exposed group had a blood lead concentration above the current threshold limit value of 3.81 mumol/l at the time of testing (mean 2.36 mumol/l, range 1.19-3.92 mumol/l) and none had been detected above that level in the previous three years. Nevertheless, most neurobehavioural functions tested showed some impairment in the lead workers. Visual sensory function was affected and, perhaps as a consequence, sustained attention and psychomotor tasks were performed more slowly by the lead exposed group. Cognitive functions were also impaired, with sensory store memory, short term memory, and learning abilities all showing deficits in lead workers. Such cognitive deficits may also be partly due to initial degradation of the visual input. Long term memory performance compared equally with control levels possibly because of development of a compensatory strategy such as rehearsal by the lead exposed subjects. Multiple linear regression analysis relating to lead workers test performance and their lead exposure showed that performance on the sensory store memory test alone was significantly related to exposure. This was probably due to the homogeneity of the lead exposed group with regard to blood lead concentrations and the use of blood lead as a measure of chronic lead exposure.

  11. Neurobehavioural effects of occupational exposure to lead

    Energy Technology Data Exchange (ETDEWEB)

    Williamson, A.M.; Teo, R.K.

    1986-06-01

    A set of neurobehavioural tests selected on the basis of information processing theory was used to study the effect of low level occupational lead exposure on 59 lead workers compared with a matched control group of the same number. Only one of the lead exposed group had a blood lead concentration above the current threshold limit value of 3.81 mumol/l at the time of testing (mean 2.36 mumol/l, range 1.19-3.92 mumol/l) and none had been detected above that level in the previous three years. Nevertheless, most neurobehavioural functions tested showed some impairment in the lead workers. Visual sensory function was affected and, perhaps as a consequence, sustained attention and psychomotor tasks were performed more slowly by the lead exposed group. Cognitive functions were also impaired, with sensory store memory, short term memory, and learning abilities all showing deficits in lead workers. Such cognitive deficits may also be partly due to initial degradation of the visual input. Long term memory performance compared equally with control levels possibly because of development of a compensatory strategy such as rehearsal by the lead exposed subjects. Multiple linear regression analysis relating to lead workers test performance and their lead exposure showed that performance on the sensory store memory test alone was significantly related to exposure. This was probably due to the homogeneity of the lead exposed group with regard to blood lead concentrations and the use of blood lead as a measure of chronic lead exposure.

  12. Initial occupational exposure to lead

    Energy Technology Data Exchange (ETDEWEB)

    Forni, A.; Cambiaghi, G.; Secchi, G.C.

    1976-01-01

    Serial chromosome and biochemical studies were carried out in 11 subjects before and during initial occupational exposure to moderate quantities of lead fumes in a storage battery plant. The rate of abnormal metaphases, mostly with chromatid and one-break chromosome aberrations, was approximately doubled after one month of work; it further increased after two months of work; remained in this range up to seven months of exposure; and then tended to decrease somewhat. Blood lead levels increased progressively in the first few months, then reached a steady state. Urinary lead and coproporphyrin levels increased sharply after one month of work, while urinary delta-aminolevulinic acid (ALA) levels increased moderately. The ALA dehydratase (ALAD) activity of red blood cells (RBCs) was reduced to almost 50 percent of the initial values after one month, decreased further in subsequent months, and remained decreased through the remainder of the study.

  13. High temperature superconductor current leads

    International Nuclear Information System (INIS)

    Zeimetz, B.; Liu, H.K.; Dou, S.X.

    1996-01-01

    Full text: The use of superconductors in high electrical current applications (magnets, transformers, generators etc.) usually requires cooling with liquid Helium, which is very expensive. The superconductor itself produces no heat, and the design of Helium dewars is very advanced. Therefore most of the heat loss, i.e. Helium consumption, comes from the current lead which connects the superconductor with its power source at room temperature. The current lead usually consists of a pair of thick copper wires. The discovery of the High Temperature Superconductors makes it possible to replace a part of the copper with superconducting material. This drastically reduces the heat losses because a) the superconductor generates no resistive heat and b) it is a very poor thermal conductor compared with the copper. In this work silver-sheathed superconducting tapes are used as current lead components. The work comprises both the production of the tapes and the overall design of the leads, in order to a) maximize the current capacity ('critical current') of the superconductor, b) minimize the thermal conductivity of the silver clad, and c) optimize the cooling conditions

  14. Current Leads, Links and Buses

    CERN Document Server

    Ballarino, A

    2014-01-01

    Electrical transfer from a room temperature power source to a superconducting system is done via conventional or superconducting current leads and superconducting buses or links. The principles of optimization of these devices are presented, with emphasis on the cryogenic, electrical, and superconductor related aspects that drive choices for a system.

  15. Current Leads, Links and Buses

    Energy Technology Data Exchange (ETDEWEB)

    Ballarino, A [European Organization for Nuclear Research, Geneva (Switzerland)

    2014-07-01

    Electrical transfer from a room temperature power source to a superconducting system is done via conventional or superconducting current leads and superconducting buses or links. The principles of optimization of these devices are presented, with emphasis on the cryogenic, electrical, and superconductor related aspects that drive choices for a system.

  16. Exposure to lead from intake of coffee

    DEFF Research Database (Denmark)

    Hansen, Max; Sloth, Jens Jørgen; Rasmussen, Rie Romme

    Food and beverages is one of the primary sources of intake of and exposure to lead, with beverages accounting for almost 50%. Previous studies from Denmark have estimated that the intake of lead from coffee is very high and may contribute to up to 20% of the total lead intake from food and bevera......Food and beverages is one of the primary sources of intake of and exposure to lead, with beverages accounting for almost 50%. Previous studies from Denmark have estimated that the intake of lead from coffee is very high and may contribute to up to 20% of the total lead intake from food...... and beverages. This estimate is, however, based on older, non-published data. In the current project extensive chemical analyses of coffee beans, drinking water and ready-to-drink coffee have been performed. The results hereof have been compared to calculations of the total intake of lead from food...... and beverages. The results show that the intake of lead from coffee is considerably lower than previously estimated and account for 4.2% and 3.3% of the total lead intake from food and beverages for Danish men and women, respectively. It can generally be concluded that the intake of lead from coffee is low...

  17. Effects of occupational lead exposure.

    Science.gov (United States)

    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.

  18. Peripheral blood signatures of lead exposure.

    Directory of Open Access Journals (Sweden)

    Heather G LaBreche

    Full Text Available BACKGROUND: Current evidence indicates that even low-level lead (Pb exposure can have detrimental effects, especially in children. We tested the hypothesis that Pb exposure alters gene expression patterns in peripheral blood cells and that these changes reflect dose-specific alterations in the activity of particular pathways. METHODOLOGY/PRINCIPAL FINDING: Using Affymetrix Mouse Genome 430 2.0 arrays, we examined gene expression changes in the peripheral blood of female Balb/c mice following exposure to per os lead acetate trihydrate or plain drinking water for two weeks and after a two-week recovery period. Data sets were RMA-normalized and dose-specific signatures were generated using established methods of supervised classification and binary regression. Pathway activity was analyzed using the ScoreSignatures module from GenePattern. CONCLUSIONS/SIGNIFICANCE: The low-level Pb signature was 93% sensitive and 100% specific in classifying samples a leave-one-out crossvalidation. The high-level Pb signature demonstrated 100% sensitivity and specificity in the leave-one-out crossvalidation. These two signatures exhibited dose-specificity in their ability to predict Pb exposure and had little overlap in terms of constituent genes. The signatures also seemed to reflect current levels of Pb exposure rather than past exposure. Finally, the two doses showed differential activation of cellular pathways. Low-level Pb exposure increased activity of the interferon-gamma pathway, whereas high-level Pb exposure increased activity of the E2F1 pathway.

  19. Lead exposure potentiates predatory attack behavior in the cat

    International Nuclear Information System (INIS)

    Li Wenjie; Han Shenggao; Gregg, T.R.; Kemp, F.W.Francis W.; Davidow, A.L.; Louria, D.B.; Siegel, Allan; Bogden, J.D.

    2003-01-01

    Epidemiologic studies have demonstrated that environmental lead exposure is associated with aggressive behavior in children; however, numerous confounding variables limit the ability of these studies to establish a causal relationship. The study of aggressive behavior using a validated animal model was used to test the hypothesis that there is a causal relationship between lead exposure and aggression in the absence of confounding variables. We studied the effects of lead exposure on a feline model of aggression: predatory (quiet biting) attack of an anesthetized rat. Five cats were stimulated with a precisely controlled electrical current via electrodes inserted into the lateral hypothalamus. The response measure was the predatory attack threshold current (i.e., the current required to elicit an attack response on 50% of the trials). Blocks of trials were administered in which predatory attack threshold currents were measured three times a week for a total of 6-10 weeks, including before, during, and after lead exposure. Lead was incorporated into cat food 'treats' at doses of 50-150 mg/kg/day. Two of the five cats received a second period of lead exposure. Blood lead concentrations were measured twice a week and were <1, 21-77, and <20 μg/dL prior to, during, and after lead exposure, respectively. The predatory attack threshold decreased significantly during initial lead exposure in three of five cats and increased after the cessation of lead exposure in four of the five cats (P<0.01). The predatory attack thresholds and blood lead concentrations for each cat were inversely correlated (r=-0.35 to -0.74). A random-effects mixed model demonstrated a significant (P=0.0019) negative association between threshold current and blood lead concentration. The data of this study demonstrate that lead exposure enhances predatory aggression in the cat and provide experimental support for a causal relationship between lead exposure and aggressive behavior in humans

  20. Lead exposure potentiates predatory attack behavior in the cat.

    Science.gov (United States)

    Li, Wenjie; Han, Shenggao; Gregg, Thomas R; Kemp, Francis W; Davidow, Amy L; Louria, Donald B; Siegel, Allan; Bogden, John D

    2003-07-01

    Epidemiologic studies have demonstrated that environmental lead exposure is associated with aggressive behavior in children; however, numerous confounding variables limit the ability of these studies to establish a causal relationship. The study of aggressive behavior using a validated animal model was used to test the hypothesis that there is a causal relationship between lead exposure and aggression in the absence of confounding variables. We studied the effects of lead exposure on a feline model of aggression: predatory (quiet biting) attack of an anesthetized rat. Five cats were stimulated with a precisely controlled electrical current via electrodes inserted into the lateral hypothalamus. The response measure was the predatory attack threshold current (i.e., the current required to elicit an attack response on 50% of the trials). Blocks of trials were administered in which predatory attack threshold currents were measured three times a week for a total of 6-10 weeks, including before, during, and after lead exposure. Lead was incorporated into cat food "treats" at doses of 50-150 mg/kg/day. Two of the five cats received a second period of lead exposure. Blood lead concentrations were measured twice a week and were cats and increased after the cessation of lead exposure in four of the five cats (Pcat were inversely correlated (r=-0.35 to -0.74). A random-effects mixed model demonstrated a significant (P=0.0019) negative association between threshold current and blood lead concentration. The data of this study demonstrate that lead exposure enhances predatory aggression in the cat and provide experimental support for a causal relationship between lead exposure and aggressive behavior in humans.

  1. Lead exposure from aluminum cookware in Cameroon

    International Nuclear Information System (INIS)

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

    2014-01-01

    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. - Highlights: • Cookware is manufactured in Cameroon from scrap aluminum including car parts. • Twenty-nine cookware samples were evaluated for their potential to leach lead. • Boiling extractions to simulate the effects of cooking released significant lead. • Potential lead exposures per serving are estimated as high as 260 μg.

  2. Lead exposure from aluminum cookware in Cameroon

    Energy Technology Data Exchange (ETDEWEB)

    Weidenhamer, Jeffrey D.; Kobunski, Peter A. [Department of Chemistry, Geology and Physics, 401 College Ave., Ashland University, Ashland, OH 44805 (United States); Kuepouo, Gilbert [Research and Education Centre for Development (CREPD), Yaounde (Cameroon); Corbin, Rebecca W. [Department of Chemistry, Geology and Physics, 401 College Ave., Ashland University, Ashland, OH 44805 (United States); Gottesfeld, Perry, E-mail: pgottesfeld@okinternational.org [Occupational Knowledge International, San Francisco, CA (United States)

    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. - Highlights: • Cookware is manufactured in Cameroon from scrap aluminum including car parts. • Twenty-nine cookware samples were evaluated for their potential to leach lead. • Boiling extractions to simulate the effects of cooking released significant lead. • Potential lead exposures per serving are estimated as high as 260 μg.

  3. Lead exposures from varnished floor refinishing.

    Science.gov (United States)

    Schirmer, Joseph; Havlena, Jeff; Jacobs, David E; Dixon, Sherry; Ikens, Robert

    2012-01-01

    We evaluated the presence of lead in varnish and factors predicting lead exposure from floor refinishing and inexpensive dust suppression control methods. Lead in varnish, settled dust, and air were measured using XRF, laboratory analysis of scrape and wipe samples, and National Institute for Occupational Safety and Health (NIOSH) Method 7300, respectively, during refinishing (n = 35 homes). Data were analyzed using step-wise logistic regression. Compared with federal standards, no lead in varnish samples exceeded 1.0 mg/cm(2), but 52% exceeded 5000 ppm and 70% of settled dust samples after refinishing exceeded 40 μg/ft(2). Refinishing pre-1930 dwellings or stairs predicted high lead dust on floors. Laboratory analysis of lead in varnish was significantly correlated with airborne lead (r = 0.23, p = 0.014). Adding dust collection bags into drum sanders and HEPA vacuums to edgers and buffers reduced mean floor lead dust by 8293 μg Pb/ft(2) (pairborne lead exposures to less than 50 μg/m(3). Refinishing varnished surfaces in older housing produces high but controllable lead exposures.

  4. Environmental lead exposure increases micronuclei in children

    DEFF Research Database (Denmark)

    Kapka, Lucyna; Baumgartner, Adolf; Siwińska, Ewa

    2007-01-01

    The objective of this pilot study was to investigate the contribution of environmental exposures to lead in the development of cytogenetic damage detected as the frequency of micronuclei (MN) in children. The other aim was to apply the MN assay in combination with fluorescence in situ hybridization...... age from an unexposed recreational area. Exposure to lead was assessed by determination of lead concentrations in blood (PbB) by atomic absorption spectrophotometry, whereas the level of selenium (Se) in serum was detected by using graphite furnace atomic-absorption spectrometry. The frequency of MN...... was determined by the cytokinesis-block MN assay and fluorescence in situ hybridization performed using a specific pan-centromeric probe. Environmental exposure to lead resulted in significantly increased levels of PbB (5.29 +/- 2.09 versus 3.45 +/- 1.20 microg/dl in controls), although the average level...

  5. Verification of radiation exposure using lead shields

    International Nuclear Information System (INIS)

    Hayashida, Keiichi; Yamamoto, Kenyu; Azuma, Masami

    2016-01-01

    A long time use of radiation during IVR (intervention radiology) treatment leads up to an increased exposure on IVR operator. In order to prepare good environment for the operator to work without worry about exposure, the authors examined exposure reduction with the shields attached to the angiography instrument, i. e. lead curtain and lead glass. In this study, the lumber spine phantom was radiated using the instrument and the radiation leaked outside with and without shields was measured by the ionization chamber type survey meter. The meter was placed at the position which was considered to be that for IVR operator, and changed vertically 20-100 cm above X-ray focus by 10 cm interval. The radiation at the position of 80 cm above X-ray focus was maximum without shield and was hardly reduced with lead curtain. However, it was reduced with lead curtain plus lead glass. Similar reduction effects were observed at the position of 90-100 cm above X-ray focus. On the other hand, the radiation at the position of 70 cm above X-ray focus was not reduced with either shield, because that position corresponded to the gap between lead curtain and lead glass. The radiation at the position of 20-60 cm above X-ray focus was reduced with lead curtain, even if without lead glass. These results show that lead curtain and lead glass attached to the instrument can reduce the radiation exposure on IVR operator. Using these shields is considered to be one of good means for IVR operator to work safely. (author)

  6. Design chart of optimum current leads

    International Nuclear Information System (INIS)

    Ishibashi, K.; Katase, A.; Maechata, K.

    1986-01-01

    The heat flow through current leads is one of major heat losses in a superconducting magnet system. To reduce the heat flow, current leads have been optimized in a complex way by varying such quantities as conductor length, cross-sectional area, heat transfer coefficient and cooling perimeter. Therefore, this study is made to simplify the design procedure, and to explain the general characteristics of the current leads. A new combined parameter which takes turbulent flow into account is introduced in the present work to enable us to draw a useful design chart. This chart gives, to a wide variety of current leads, detailed information about the optimum design-viz. geometric dimensions, heat flow into liquid helium, and pressure drop of the cooling gas. Change of the cross-sectional area along the conductor may improve the current lead performance. The effects of this area change are examined in detail

  7. High-temperature superconducting current leads

    Science.gov (United States)

    Hull, J. R.

    1992-07-01

    The use of high-temperature superconductors (HTSs) for current leads to deliver power to devices at liquid helium temperature is near commercial realization. The use of HTSs in this application has the potential to reduce refrigeration requirements and helium boiloff to values significantly lower than the theoretical best achievable with conventional leads. Considerable advantage is achieved by operating these leads with an intermediate temperature heat sink. The HTS part of the lead can be made from pressed and sintered powder. Powder-in-tube fabrication is also possible, however, the normal metal part of the lead acts as a thermal short and cannot provide much stabilization without increasing the refrigeration required. Lead stability favors designs with low current density. Such leads can be manufactured with today's technology, and lower refrigeration results from the same allowable burnout time. Higher current densities result in lower boiloff for the same lead length, but bumout times can be very short. In comparing experiment to theory, the density of helium vapor needs to be accounted for in calculating the expected boiloff. For very low-loss leads, two-dimensional heat transfer and the state of the dewar near the leads may play a dominant role in lead performance.

  8. OCCUPATIONAL LEAD EXPOSURE AND COGNITION IN ADULTS

    Directory of Open Access Journals (Sweden)

    Veselinka Nestorova

    2018-06-01

    Full Text Available Chronic neurotoxicity of lead is a major problem in all countries around the world. Long-term exposure to lead in the environment has recently become of interest as a possible risk factor for cognitive impairment in workers exposed to lead. The consequences for the brain after cessation of the exposure are also subject to research. The aims of our study were: to investigate and analyze cognitive impairment in workers in professional contact with lead. For the purpose of the study, a total of 72 workers in chronic professional contact with lead aerosols were examined. The investigated men (n = 72 were aged 39.4 ± 10.4 (19 - 58 years with an average duration of service of 13.0 ± 8.7 (1 - 33 years and mean lead concentration in blood of 43.4 ± 9.0 μg / dl. The screening set included a subjective cognitive impairment survey, a depression scale, a set of cognitive tests (MMSE, IST, DRT, CDT, and a scale for activities of daily living (4-IADL Score. With the increase of lead levels in the blood, a statistically reliable trend is observed for decrease of MMSE, IST and CDT scores. Eleven of the screened individuals (15.28% achieved a score of <7 which determines them as positively screened according to DRT. Possible mild cognitive impairment manifesting with disturbance of construction praxis, planning, short-term memory and concentration could probably be attributed to the toxic effects of lead and has a potential to be a subclinical marker.

  9. Current practice in transvenous lead extraction

    DEFF Research Database (Denmark)

    Bongiorni, Maria Grazia; Blomström-Lundqvist, Carina; Kennergren, Charles

    2012-01-01

    AIM: Current practice with regard to transvenous lead extraction among European implanting centres was analysed by this survey. METHODS AND RESULTS: Among all contacted centres, 164, from 30 countries, declared that they perform transvenous lead extraction and answered 58 questions...... with a compliance rate of 99.9%. Data from the survey show that there seems to be an overall increasing experience of managing various techniques of lead extraction and a widespread involvement of cardiac centres in this treatment. Results and complication rates seem comparable with those of main international...... registries. CONCLUSION: This survey gives an interesting snapshot of lead extraction in Europe today and gives some clues for future research and prospective European registries....

  10. CURRENT LEVELS OF MEDICAL EXPOSURE IN RUSSIA

    Directory of Open Access Journals (Sweden)

    M. I. Balonov

    2015-01-01

    Full Text Available We considered conditions of patients’ medical radiation exposure in Russian diagnostic radiology and nuclear medicine basing on the data of our own research, of the Unified system of individual dose control and of some relevant literature. We analyzed the data on the number of diagnostic examinations, patients’ individual and collective doses and their distribution by examination types. Time trends of the studied parameters are presented for the period between 1999 and 2013. Current level of Russian patients’ medical exposure is the lowest over the whole observation period and one of the lowest among the developed countries. The annual number of X-ray diagnostic examinations is 1.8 per capita. In 2013 median effective dose of medical exposure per capita in Russia was 0.45 mSv and median dose per procedure was 0.25 mSv. The major contribution to collective dose of medical exposure was from computed tomography and radiography; the largest individual doses were caused by interventional radiology, computed X-Ray and nuclear medicine tomographic examinations. The range of median doses comprises about four orders of magnitude, i.e. from several microSv in dental X-ray examinations up to several tens of milliSv in interventional and multistage tomographic examinations. The median effective dose of adult patients increases by about an order of magnitude with each transition from dental X-ray examinations to conventional radiology and further to computed tomography and interventional radiology examinations. During interventional X-Ray examinations, absorbed skin doses at radiation beam entrance site may reach several Gray, which may lead to deterministic radiation effects in skin and subcutaneous tissues. Due to replacement of low-dose ‘functional’ nuclear medicine examinations with more informative modern scintigraphy and tomography examination, patient doses substantially increased over the last decade. With current trend for re-equipment of

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

    Directory of Open Access Journals (Sweden)

    Nan-Hung Hsieh

    2017-05-01

    Full Text Available Abstract Background 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. Methods 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. Results 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. Conclusions 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.

  12. Aggregate-level lead exposure, gun violence, homicide, and rape.

    Science.gov (United States)

    Boutwell, Brian B; Nelson, Erik J; Qian, Zhengmin; Vaughn, Michael G; Wright, John P; Beaver, Kevin M; Barnes, J C; Petkovsek, Melissa; Lewis, Roger; Schootman, Mario; Rosenfeld, Richard

    2017-01-01

    An increasing body of research has linked the geographic distribution of lead with various indicators of criminal and antisocial behavior. The current study, using data from an ongoing project related to lead exposure in St. Louis City, MO, analyzed the association between aggregate blood lead levels and specific indicators violent crime within the city. Ecological study. St. Louis, Missouri. Blood lead levels. Official reports of violent crimes were categorized as 1) crimes involving a firearm (yes/no), 2) assault crimes (with or without a firearm), 3) robbery crimes (with or without a firearm), 4) homicides and 5) rape. With the exception of rape, aggregate blood-lead levels were statistically significant predictors of violent crime at the census tract level. The risk ratios for each of the outcome measures were as follows: firearm crimes 1.03 (1.03-1.04), assault crimes 1.03 (1.02-1.03), robbery crimes 1.03 (1.02-1.04), homicide 1.03 (1.01, 1.04), and rape 1.01 (0.99-1.03). Extending prior research in St. Louis, results suggest that aggregated lead exposure at the census tract level predicted crime outcomes, even after accounting for important sociological variables. Moving forward, a more developed understanding of aggregate level crime may necessitate a shift toward studying the synergy between sociological and biological risk factors such as lead exposure.

  13. Assessment of Child Lead Exposure in a Philadelphia Community, 2014.

    Science.gov (United States)

    Dignam, Timothy; Pomales, Ana; Werner, Lora; Newbern, E Claire; Hodge, James; Nielsen, Jay; Grober, Aaron; Scruton, Karen; Young, Rand; Kelly, Jack; Brown, Mary Jean

    2018-01-10

    Several urban neighborhoods in Philadelphia, Pennsylvania, have a history of soil, household lead paint, and potential lead-emitting industry contamination. To (1) describe blood lead levels (BLLs) in target neighborhoods, (2) identify risk factors and sources of lead exposure, (3) describe household environmental lead levels, and (4) compare results with existing data. A simple, random, cross-sectional sampling strategy was used to enroll children 8 years or younger living in selected Philadelphia neighborhoods with a history of lead-emitting industry during July 2014. Geometric mean of child BLLs and prevalence of BLLs of 5 μg/dL or more were calculated. Linear and logistic regression analyses were used to ascertain risk factors for elevated BLLs. Among 104 children tested for blood lead, 13 (12.4%; 95% confidence interval [CI], 7.5-20.2) had BLLs of 5 μg/dL or more. The geometric mean BLL was 2.0 μg/dL (95% CI, 1.7-2.3 μg/dL). Higher geometric mean BLLs were significantly associated with front door entryway dust lead content, residence built prior to 1900, and a child currently or ever receiving Medicaid. Seventy-one percent of households exceeded the screening level for soil, 25% had an elevated front door floor dust lead level, 28% had an elevated child play area floor dust lead level, and 14% had an elevated interior window dust lead level. Children in households with 2 to 3 elevated environmental lead samples were more likely to have BLLs of 5 μg/dL or more. A spatial relationship between household proximity to historic lead-emitting facilities and child BLL was not identified. Entryway floor dust lead levels were strongly associated with blood lead levels in participants. Results underscore the importance to make housing lead safe by addressing all lead hazards in and around the home. Reduction of child lead exposure is crucial, and continued blood lead surveillance, testing, and inspection of homes of children with BLLs of 5 μg/dL or more to identify

  14. Lead Exposure Induces Telomere Instability in Human Cells.

    Directory of Open Access Journals (Sweden)

    Géraldine Pottier

    Full Text Available Lead (Pb is an important environmental contaminant due to its widespread use over many centuries. While it affects primarily every organ system of the body, the most pernicious effects of Pb are on the central nervous system leading to cognitive and behavioral modification. Despite decades of research, the mechanisms responsible for Pb toxicity remain poorly understood. Recent work has suggested that Pb exposure may have consequences on chromosomal integrity as it was shown that Pb exposure leads to the generation of γH2Ax foci, a well-established biomarker for DNA double stranded break (DSB formation. As the chromosomal localization of γH2Ax foci plays an important role in determining the molecular mechanism responsible for their formation, we examined the localization of Pb-induced foci with respect to telomeres. Indeed, short or dysfunctional telomeres (uncapped or damaged telomeres may be recognized as DSB by the DNA repair machinery, leading to "telomere-Induced Foci" (TIFs. In the current study, we show that while Pb exposure did not increase intra-chromosomal foci, it significantly induced TIFs, leading in some cases, to chromosomal abnormalities including telomere loss. The evidence suggests that these chromosomal abnormalities are likely due to perturbation of telomere replication, in particular on the lagging DNA strand. We propose a mechanism by which Pb exposure leads to the loss of telomere maintenance. As numerous studies have demonstrated a role for telomere maintenance in brain development and tissue homeostasis, our results suggest a possible mechanism for lead-induced neurotoxicity.

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

    Science.gov (United States)

    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

  16. Dietary exposure to lead in the Netherlands

    NARCIS (Netherlands)

    Boon PE; te Biesebeek JD; van Donkersgoed G; VVH; V&Z

    2017-01-01

    Uptake from the soil is the main route by which lead ends up in food. Lead in soil has its origin in both natural and anthropogenic sources. The lead concentration in food has decreased over the last decennia by the use of unleaded petrol and paint, and the replacement of lead water pipes.

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

    OpenAIRE

    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 asso...

  18. In vivo x-ray fluorescence of bone lead in the study of human lead metabolism: Serum lead, whole blood lead, bone lead, and cumulative exposure

    International Nuclear Information System (INIS)

    Cake, K.M.; Chettle, D.R.; Webber, C.E.; Gordon, C.L.

    1995-01-01

    Traditionally, clinical studies of lead's effect on health have relied on blood lead levels to indicate lead exposure. However, this is unsatisfactory because blood lead levels have a half-life of approximately 5 weeks, and thus reflect recent exposure. Over 90% of the lead body burden is in bone, and it is thought to have a long residence time, thus implying that measurements of bone lead reflect cumulative exposure. So, measurements of bone lead are useful in understanding the long-term health effects of lead. Ahlgren reported the first noninvasive measurements of bone lead in humans, where γ-rays from 57 Co were used to excite the K series x-rays of lead. The lead detection system at McMaster University uses a 109 Cd source which is positioned at the center of the detector face (HPGe) and a near backscatter (∼160 degrees) geometry. This arrangement allows great flexibility, since one can sample lead in a range of different bone sites due to a robust normalization technique which eliminates the need to correct for bone geometry, thickness of overlying tissue, and other related factors. The effective radiation dose to an adult during an x-ray fluorescence bone lead measurement is extremely low, being 35 nSv. This paper addresses the issue of how bone, whole blood, and serum lead concentrations can be related in order to understand a person's lead exposure history

  19. Lead exposure among young urban women

    Directory of Open Access Journals (Sweden)

    Moline Jacqueline M.

    1999-01-01

    Full Text Available Objective. Blood lead levels have declined among every age group in the United States, but urban minority residents remain at disproportionate risk for elevated lead levels. Our objective was to measure lead burden in young women of childbearing age in New York City. We also describe successful means of recruiting this population into a cohort study. Material and methods. Healthy women aged 18-25 attending a New York City health care center in 1995-1998 were eligible for participation. Participants were recruited by health care providers, the study coordinator and the participants themselves. Venous blood samples were obtained for whole blood lead, ferritin and hematocrit measurements, and detailed questionnaires were administered. Results. 239 women have been recruited to date. The population is predominately minority: 62% African-American, 33% Hispanic and 5% Caucasian/Asian. The average age of participants is 19.3 years. Recruitment of participants into the study is predominantly (55% through "word of mouth" from previously enrolled participants. Few participants learned of the study through their health care providers. The mean blood lead level among study participants is 2.1 ± 1.7 µg/dl, which is consistent with the most recent United States national survey. Conclusions. Blood lead levels are low in young, urban minority women of childbearing age in New York City. In this population, recruitment efforts were substantially enhanced with the help of enrolled participants and the health care community.

  20. Effect of lead exposure in children

    International Nuclear Information System (INIS)

    Khwaja, M.

    2005-01-01

    Increasing prosperity and population-growth in many developing countries are resulting in accelerated growth in population of vehicles and vehicle-kilometers traveled. In Pakistan also, the number of vehicles has jumped from 0.8 million to about 4.0 million within 20 years, showing an overall increase of more than 400%. Accordingly, the consumption of petrol (motor spirit) has increased from 828,670 metric tons to 1,189,042 metric tons. The high content of lead in petrol is a serious issue, as the end- product is the release of lead into the environment. In Pakistan, prior to July 2001, lead-content in petrol was reported to be as high as 0.35-0.84 gram per liter. The reported lead-levels in air (micrograms/cubic centimeter) in different cities of Pakistan are: Karachi (1980-81) 0.13-0.24; Peshawar (1994-95) 0.21-0.79; Lahore (1993-94) 0.15-8.36 and (1999-2000) 0.89-7.85 and Rawalpindi (1999-2000) 0.71-10.00, indicating the very alarming increase and high levels of lead in the ambient air, at the reported sites and time of monitoring. Children in developing countries, with dietary deficiencies, are very susceptible to lead poisoning. Special concern of lead-poisoning has been that lead is a neurotoxin and it impairs brain-development in children, even at levels that were considered safe. The overall mean BPbLs (micrograms per deciliter) among 900 (boys and girls) of three cities in Pakistan have been reported to be 22.8 +- 3.30, 19.00 +-6.48 and 2.30 +-0.19 (rural site). Details of these investigations and government national environmental action-plan (NEAP) are described and discussed in this paper, with special reference to clean air by providing clean fuel and taking other air-pollution control measures. (author)

  1. Exposure to lead in South African shooting ranges

    International Nuclear Information System (INIS)

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

    2017-01-01

    Introduction: 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. Methods: An analytical cross sectional study was conducted, with participants recruited from four randomly selected shooting ranges and three archery ranges as a comparator group. Results: 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 ≥10 μg/dl (p<0.001). Conclusion: 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. - Highlights: • This is the first study, to our knowledge, of lead exposure in shooting ranges in an African setting. • This study indicates highly elevated lead exposure amongst the users of certain private shooting ranges in South Africa. • Lead exposure may be a serious, yet under-studied, source of adult lead exposure in South Africa, and possibly elsewhere on the African continent.

  2. Exposure to lead in South African shooting ranges

    Energy Technology Data Exchange (ETDEWEB)

    Mathee, Angela [South African Medical Research Council, Environment & Health Research Unit, PO Box 87373, Houghton 2041 (South Africa); University of the Witwatersrand (School of Public Health), PO Box Wits, Johannesburg 2050 (South Africa); University of Johannesburg (Environmental Health Department, Faculty of Health Sciences), PO Box 524, Auckland Park, Johannesburg 2006 (South Africa); Jager, Pieter de [University of the Witwatersrand (School of Public Health), PO Box Wits, Johannesburg 2050 (South Africa); National Health Laboratory Service (Epidemiology and Surveillance Unit, National Institute for Occupational Health), PO Box 4788, Johannesburg 2000 (South Africa); Naidoo, Shan [University of the Witwatersrand (School of Public Health), PO Box Wits, Johannesburg 2050 (South Africa); Naicker, Nisha [South African Medical Research Council, Environment & Health Research Unit, PO Box 87373, Houghton 2041 (South Africa); University of the Witwatersrand, School of Public Health, PO Box Wits, Johannesburg 2050 (South Africa); University of Johannesburg, Environmental Health Department, Faculty of Health Sciences, PO Box 524, Auckland Park, Johannesburg 2006 (South Africa)

    2017-02-15

    Introduction: 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. Methods: An analytical cross sectional study was conducted, with participants recruited from four randomly selected shooting ranges and three archery ranges as a comparator group. Results: 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 ≥10 μg/dl (p<0.001). Conclusion: 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. - Highlights: • This is the first study, to our knowledge, of lead exposure in shooting ranges in an African setting. • This study indicates highly elevated lead exposure amongst the users of certain private shooting ranges in South Africa. • Lead exposure may be a serious, yet under-studied, source of adult lead exposure in South Africa, and possibly elsewhere on the African continent.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  5. Childhood Lead Exposure from Battery Recycling in Vietnam

    Directory of Open Access Journals (Sweden)

    William E. Daniell

    2015-01-01

    Full Text Available 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.

  6. Childhood Lead Exposure from Battery Recycling in Vietnam.

    Science.gov (United States)

    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.

  7. Lead remediation and changes in human lead exposure: some physiological and biokinetic dimensions.

    Science.gov (United States)

    Mushak, Paul

    2003-02-15

    This paper presents a qualitative and quantitative analysis of the various aspects of lead remediation effectiveness with particular reference to human health risk assessment. One of the key elements of lead remediation efforts at such sites as those under the Superfund program deals with populations at elevated exposure and toxicity risk in the proximity of, or at, the site of remediation, especially remediation workers, workers at other tasks on sites that were remediated down to some action level of lead concentration in soils, and groups at risk in nearby communities. A second element has to do with how one measures or models lead exposure changes with special reference to baseline and post-remediation conditions. Various biomarkers of lead exposure can be employed, but their use requires detailed knowledge of what results using each means. The most commonly used approach is measurement of blood lead (Pb-B). Recognized limitations in the use of Pb-B has led to the use of predictive Pb exposure models, which are less vulnerable to the many behavioral, physiological, and environmental parameters that can distort isolated or 'single shot' Pb-B testings. A third aspect covered in this paper presents various physiological factors that affect the methods by which one evaluates Pb remediation effectiveness. Finally, this article offers an integrated look at how lead remediation actions directed at one lead source or pathway affect the total lead exposure picture for human populations at elevated lead exposure and toxicity risk.

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

    International Nuclear Information System (INIS)

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

    2008-01-01

    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 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

  9. Lead concentrations and risk exposure assessment in surface soils ...

    African Journals Online (AJOL)

    Lead concentrations and risk exposure assessment in surface soils at residential lands previously used for auto-mechanic and auto-welding activities in Port Harcourt, Nigeria. ... Journal of Applied Sciences and Environmental Management.

  10. The philosophy and assumptions underlying exposure limits for ionising radiation, inorganic lead, asbestos and noise

    International Nuclear Information System (INIS)

    Akber, R.

    1996-01-01

    Full text: A review of the literature relating to exposure to, and exposure limits for, ionising radiation, inorganic lead, asbestos and noise was undertaken. The four hazards were chosen because they were insidious and ubiquitous, were potential hazards in both occupational and environmental settings and had early and late effects depending on dose and dose rate. For all four hazards, the effect of the hazard was enhanced by other exposures such as smoking or organic solvents. In the cases of inorganic lead and noise, there were documented health effects which affected a significant percentage of the exposed populations at or below the [effective] exposure limits. This was not the case for ionising radiation and asbestos. None of the exposure limits considered exposure to multiple mutagens/carcinogens in the calculation of risk. Ionising radiation was the only one of the hazards to have a model of all likely exposures, occupational, environmental and medical, as the basis for the exposure limits. The other three considered occupational exposure in isolation from environmental exposure. Inorganic lead and noise had economic considerations underlying the exposure limits and the exposure limits for asbestos were based on the current limit of detection. All four hazards had many variables associated with exposure, including idiosyncratic factors, that made modelling the risk very complex. The scientific idea of a time weighted average based on an eight hour day, and forty hour week on which the exposure limits for lead, asbestos and noise were based was underpinned by neither empirical evidence or scientific hypothesis. The methodology of the ACGIH in the setting of limits later brought into law, may have been unduly influenced by the industries most closely affected by those limits. Measuring exposure over part of an eight hour day and extrapolating to model exposure over the longer term is not the most effective way to model exposure. The statistical techniques used

  11. Some studies of maternal and infant lead exposure in Glasgow

    Energy Technology Data Exchange (ETDEWEB)

    Moore, M.R.; Goldberg, A.; Pocock, S.J.; Meredith, A.; Stewart, I.M.; MacAnespie, H.; Lees, R.; Low, A.

    1982-04-01

    In two studies in the city of Glasgow, 236 mothers and their newly born infants and 117 mothers and their 6-weeks old children's environmental lead exposure were examined. In both studies blood lead concentrations were found to correlate significantly with the cube root of the domestic water lead concentrations. In the first study, multiple regression analyses of maternal blood lead and cord blood lead concentrations on other variables showed a significant negative correlation with gestational age. It was also noted that there was an annual fluctuation in maternal blood lead concentration with highest values in the autumn. In the second study, similar relationships were found. Although there was no association between blood lead and sex, age, place of birth or feeding method, as in the previous study, a significant association between social class and blood lead was found. This could be explained on the basis of the significant correlation between water lead and social class. In those mothers who breast fed, breast milk lead concentrations were found to correlate significantly with blood lead concentrations where breast milk lead was around one tenth of blood lead concentration. These studies emphasise the importance of water lead in the economy of environmental lead exposure to mothers and their unborn and newly born infants.

  12. Environmental lead exposure risks associated with children's outdoor playgrounds

    International Nuclear Information System (INIS)

    Taylor, Mark Patrick; Camenzuli, Danielle; Kristensen, Louise Jane; Forbes, Miriam; Zahran, Sammy

    2013-01-01

    This study examines exposure risks associated with lead smelter emissions at children's public playgrounds in Port Pirie, South Australia. Lead and other metal values were measured in air, soil, surface dust and on pre- and post-play hand wipes. Playgrounds closest to the smelter were significantly more lead contaminated compared to those further away (t(27.545) = 3.76; p = .001). Port Pirie post-play hand wipes contained significantly higher lead loadings (maximum hand lead value of 49,432 μg/m 2 ) than pre-play hand wipes (t(27) = 3.57, p = .001). A 1% increase in air lead (μg/m 3 ) was related to a 0.713% increase in lead dust on play surfaces (95% CI, 0.253–1.174), and a 0.612% increase in post-play wipe lead (95% CI, 0.257–0.970). Contaminated dust from smelter emissions is determined as the source and cause of childhood lead poisoning at a rate of approximately one child every third day. -- Highlights: •Spatial and temporal variations in lead exposure due to smelter emissions is examined. •Exposure to lead and other metals is evaluated using pre and post-play hand wipe measures. •The relationship of smelter emissions to surface and hand lead exposures is modelled. •A 1% increase in air lead (μg/m 3 ) was related to a 0.713% increase in lead dust on play surfaces. -- Playgrounds in Port Pirie are seriously contaminated by smelter emissions, with levels of surface dust and hand dust that pose a significant risk of harm to human health

  13. Estimating the burden of disease attributable to lead exposure in ...

    African Journals Online (AJOL)

    Objectives. To estimate the burden of disease attributable to lead exposure in South Africa in 2000. Design. World Health Organization comparative risk assessment (CRA) methodology was followed. Recent community studies were used to derive mean blood lead concentrations in adults and children in urban and rural ...

  14. Design and application consideration of high temperature superconducting current leads

    International Nuclear Information System (INIS)

    Wu, J.L.

    1994-01-01

    As a potential major source of heat leak and the resultant cryogen boiloff, cryogenic current leads can significantly affect the refrigeration power requirement of cryogenic power equipment. Reduction of the heat leak associated with current leads can therefore contribute to the development and application of this equipment. Recent studies and tests have demonstrated that, due to their superconducting and low thermal conductivity properties, ceramic high temperature superconductor (HTSC) can be employed in current leads to significantly reduce the heat leak. However, realization of this benefit requires special design considerations pertaining to the properties and the fabrication technology of the relatively new ceramic superconductor materials. Since processing and fabrication technology are continuously being developed in the laboratories, data on material properties unrelated to critical states are quite limited. Therefore, design analysis and experiments have to be conducted in tandem to achieve a successful development. Due to the rather unique combination of superconducting and thermal conductivities which are orders of magnitude lower than copper, ceramic superconductors allow expansion of the operating scenarios of current leads. In addition to the conventional vapor-cooled lead type application, low heat leak conduction-cooled type current leads may be practical and are being developed. Furthermore, a current lead with an intermediate heat leak intercept has been successfully demonstrated in a multiple current lead assembly employing HTSC. These design and application considerations of high temperature superconducting current leads are addressed here

  15. Oral lead bullet fragment exposure in northern bobwhite (Colinus virginianus).

    Science.gov (United States)

    Kerr, Richard; Holladay, Jeremy; Holladay, Steven; Tannenbaum, Lawrence; Selcer, Barbara; Meldrum, Blair; Williams, Susan; Jarrett, Timothy; Gogal, Robert

    2011-11-01

    Lead (Pb) is a worldwide environmental contaminant known to adversely affect multiple organ systems in both mammalian and avian species. In birds, a common route of exposure is via oral ingestion of lead particles. Data are currently lacking for the retention and clearance of Pb bullet fragments in gastrointestinal (GI) tract of birds while linking toxicity with blood Pb levels. In the present study, northern bobwhite quail fed a seed-based diet were orally gavaged with Pb bullet fragments (zero, one or five fragments/bird) and evaluated for rate of fragment clearance, and changes in peripheral blood, renal, immune, and gastrointestinal parameters. Based on radiographs, the majority of the birds cleared or absorbed the fragments by seven days, with the exception of one five-fragment bird which took between 7 and 14 days. Blood Pb levels were higher in males than females, which may be related to egg production in females. In males but not females, feed consumption, body weight gain, packed cell volume (PCV), plasma protein concentration, and δ-aminolevulinic acid dehydratase (δ-ALAD) activity were all adversely affected by five Pb fragments. Birds of both sexes that received a single Pb fragment displayed depressed δ-ALAD, suggesting altered hematologic function, while all birds dosed with five bullet fragments exhibited greater morbidity.

  16. E-Waste Informal Recycling: An Emerging Source of Lead Exposure in South America.

    Science.gov (United States)

    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 based paint (r = 0.23; P 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.

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

    Science.gov (United States)

    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.

  18. Occupational exposure to lead--granulometric distribution of airborne lead in relation to risk assessment.

    Science.gov (United States)

    Carelli, G; Masci, O; Altieri, A; Castellino, N

    1999-07-01

    The amount of airborne lead absorbed by the body during occupational exposure depends not only on lead concentration in workplace air, but also on the granulometric distribution of the aerosol. The Occupational Safety and Health Administration (OSHA) set the lead Permissible Exposure Limit (PEL) at 50 micrograms/m3 on the basis of Bernard's model and a number of assumptions, including assumption "C", which predicts that the first 12.5 micrograms/m3 are made up of fine particles (aerodynamic diameter 1 micron. Occupational exposure to airborne lead at a concentration of 50 micrograms/m3 and a granulometric distribution calculated according to the above mentioned assumption, leads, in the model, to a mean blood level of 40 micrograms/dl. In the present study, we tested the validity of assumption "C" in the environmental air of a factory that manufactured crystal glassware containing 24% lead oxide. An 8-stage impactor was used to measure the particle size of airborne dust collected from personal and area samplings. Results indicate that, on the whole, assumption "C" cannot be considered valid in the work environment investigated in this study. As a result, lead absorption levels in exposed workers may be noticeably different from those predicted by the OSHA model. We therefore suggest that in order to make a correct evaluation of the risk of occupational exposure to lead, it is essential to integrate total airborne lead concentration with a measurement of the granulometric distribution of the aerosol.

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

    Science.gov (United States)

    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.

  20. Lead toxicity on hematological parameters in workers with occupational exposure to lead

    International Nuclear Information System (INIS)

    Dursun, N.; Koese, K.

    1998-01-01

    The effects of lead on hematological parameters were studied in lead exposed male workers occupied for 17.84+-4.22 years in a metal powder producing factory in Kayseri, Turkey and control male workers in same city. Blood lead and plasma zinc levels were measured by Atomic Absorption Spectrophotometry (AAS) and hematological parameters by Culture Counter S. The lead exposure workers had higher lead levels (13.81+- 9.21 mug/dl) as compared to control subjects (2.37+-0.10 mug/dl). No difference was observed in the plasma zinc levels of both groups. As indices of lead exposure, red blood cell (RBC) counts, hemoglobin (Hb), and hematocrit (Hct) values significantly decreased. Mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), and mean corpuscular haemoglobin concentration (MCHC) significantly increased except MCV. There was also an increase in MCV, but it was not significant. (author)

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

    International Nuclear Information System (INIS)

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

    2006-01-01

    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 mg kg -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. - Children were exposed to soil lead and the exposure was assessed by bioaccessibility using in vitro digestion model in a modified version

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

    Science.gov (United States)

    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.

  3. Activity of lead deposited in the tissues in conditions of occupational lead exposure

    Energy Technology Data Exchange (ETDEWEB)

    1974-01-01

    The author measured urinary excretion of delta-aminolevulinic acid (ALA), coproporphyrins and lead, before and after administration of chelating agents (CaEDTA and D-penicillamine) to subjects presenting clinical symptoms of lead poisoning and workers occupationally exposed to lead. He found a great increase in lead following its mobilization in subjects with lead poisoning who had previously shown a high level of haemoglobin precursors and a low urinary lead level. In these subjects ALA excretion was proportional to the duration of exposure. A correlation was found between urinary ALA and coproporphyrins, on the one hand, and lead excretion after provocation, on the other. This suggests that the lead deposited in the tissues, as well as that in circulation, retains all its activity.

  4. Effects of experimental lead exposure and the therapeutic effect of ...

    African Journals Online (AJOL)

    Effects of experimental lead exposure and the therapeutic effect of defatted Moringa oleifera seed meal on serum electrolytes levels of Wistar rats. IS Idoko, IC Ugochukwu, SE Abalaka, AM Adamu, PK Columbus, YA Kwabugge, RE Edeh, S Adamu, B Muhammed ...

  5. Exposure to lead and specific attentional problems in schoolchildren.

    NARCIS (Netherlands)

    Minder, B.; Das-Smaal, E.A.; Brand, E.F.J.M.; Orlebeke, J.F.

    1994-01-01

    A pilot study was carried out to investigate the relationship between exposure to lead and attention in children. The participants were 43 boys, 8 to 12 years of age, attending special schools for children with educational and/or learning problems (so called LOM schools). Children with probable

  6. Lead exposures in U.S. Children, 2008: implications for prevention.

    Science.gov (United States)

    Levin, Ronnie; Brown, Mary Jean; Kashtock, Michael E; Jacobs, David E; Whelan, Elizabeth A; Rodman, Joanne; Schock, Michael R; Padilla, Alma; Sinks, Thomas

    2008-10-01

    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. 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. 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 >or=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. 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.

  7. Letter to editor: Blood pressure, hypertension and lead exposure.

    Science.gov (United States)

    Yang, Wen-Yi; Staessen, Jan A

    2018-02-19

    A significant association of office diastolic blood pressure with low-level blood lead exposure was reported in a Brazilian adult population. However, caution should be taken to interpret these results. The multivariable-adjusted association with blood pressure was positive for diastolic blood pressure, but inverse for systolic blood pressure. The association sizes were infinitesimal without clinical relevance. The outcome measures, i.e. blood pressure and the prevalence of hypertension were analysed across categories of the blood lead distribution - not in relation to blood lead as continuous variable. Blood pressure was the average of two oscillometric office readings, whereas ambulatory monitoring is the state-of-the-art.

  8. Lead elimination by ICRF 158 in rats after chronic lead exposure

    Energy Technology Data Exchange (ETDEWEB)

    Witting, U; Hultsch, E

    1981-02-01

    Lead elimination by ICRF 158, a lipophilic derivative of ethylene-diaminetetra-acetate (EDTA), was investigated in rats after chronic lead exposure. The animals had received a lead concentration of 550 ppm in their drinking water for 140 days. Subsequent treatment with ICRF 158 for 30 days led to increased mobilization and elimination of incorporated lead, and the lead-induced inhibition of hemosynthesis was removed. ICR 158 produced no renal damage in excess to lead-induced tubular nephrosis. Separate toxicity tests in mice demonstrated that is less toxic than CaNa/sub 2/EDTA. ICRF 158 does not form stable complexes with lead ions in vitro. The mechanism of action of this lipophilic EDTA derivative is compared to that of its hydrophilic correspondent, the chelating agent CaNa/sub 2/EDTA.

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

    Science.gov (United States)

    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 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.

  10. 600 a Current Leads with Dry and Compact Warm Terminals

    CERN Document Server

    Andersen, T P; Vullierme, B

    2002-01-01

    For the LHC magnet test benches 26 pairs of conventional helium vapour-cooled 600 A current leads are required. The first pair of 600 A current leads has been designed and built by industry and tested at CERN. The main component of the lead is the heat exchanger, which consists of two concentric copper pipes. Special attention was also given to the design of the warm terminal in order to avoid any condensation and to resist at an electrical test of 2 kV. The paper describes construction details and compares calculated and measured values of the main parameters.

  11. Embryonic exposure to lead: comparison of immune and cellular responses in unchallenged and virally stressed chickens

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ji-Eun; Kao, Elizabeth; Dietert, Rodney R. [Institute for Comparative and Environmental Toxicology, College of Veterinary Medicine, Cornell University, Ithaca, NY (United States); Department of Microbiology and Immunology, College of Veterinary Medicine, Cornell University, Ithaca, NY (United States); Naqi, Syed A. [Department of Microbiology and Immunology, College of Veterinary Medicine, Cornell University, Ithaca, NY (United States)

    2002-01-01

    Lead, a ubiquitous environmental contaminant, has been shown to modulate various functions of the immune system and decrease host resistance to infectious disease. However, limited information is available concerning the direct effects of lead on the host immune response to an infectious agent after developmental exposure. The current study utilized chickens to examine the effect of embryonic lead exposure on immune and cellular responses during viral challenge. Sublethal doses of lead were introduced into fertilized Cornell K Strain White Leghorn chicken eggs via the air sac at day 5 or day 12 of embryonic development (designated as E5 and E12, respectively). Four-week-old female chickens were inoculated with infectious bronchitis virus (IBV) strain M41. Antibody titer to IBV, delayed-type hypersensitivity (DTH) response against bovine serum albumin (BSA), the absolute number and percentage of leukocyte subpopulations, and interferon-{gamma} (IFN-{gamma})-like cytokine production by splenocytes were evaluated at 5-6 weeks of age. While antibody response to IBV in juvenile chicks was unaffected by the in ovo lead exposure, IFN-{gamma}-like cytokine production by splenocytes was significantly depressed following lead exposure at both developmental stages. In contrast with this pattern, the DTH response against BSA was unaffected following E5 exposure, but was significantly decreased after E12 exposure to lead. These changes were similar to those previously reported in chickens not exposed to IBV. While lead exposure at E5 induced significant changes in the percentage of circulating heterophils at 1 day postinfection (dpi), lead did not cause any change in relative leukocyte counts after E12 exposure. At 7 dpi, E5 lead exposure resulted in decreased absolute number and percentage of circulating lymphocytes, while total leukocyte counts, and the absolute number and percentage of circulating monocytes and heterophils were significantly reduced in E12 lead

  12. [The influence of occupational lead exposure on transmural repolarization dispersion].

    Science.gov (United States)

    Zyśko, Dorota; Gajek, Jacek; Chlebda, Ewa; Mazurek, Walentyna

    2005-02-01

    The parts of QT interval: time from Q wave to the peak of T wave (QTp) representing the de- and repolarization of subepicardial layer and the time from the peak of T wave to its end (QTp-e) building the transmural dispersion of repolarization enable more exact assessment of repolarization period of the heart muscle. Occupational exposure to lead influences the electrophysiologic properties of the heart. The aim of our study was to assess the QTp and QTp-e interval in workers occupationally exposed to lead. The study was carried out in 22 copper smelters aged 41.8 +/- 8.7 years, occupationally exposed to lead. The control group consisted of 14 healthy men. In all studied subjects blood lead concentration (Pb) and the concentration of free protoporphyrins in erytrocytes were assessed. 24-hour ECG holter monitoring was done to study rhythm disturbances and the duration in lead CM5 of QT interval, QTp interval, RR interval preceding the assessed QT interval (pRR) during sleep, rest during the awake state and moderate daily activity. The QTp-e interval is the difference between the duration of QT and QTp interval. The duration of QTp and QTp-e in occupationally exposed workers and healthy persons did not differ significantly. These parameters were significantly lower in both groups during moderately physical activity comparing to the values during sleep. The QTp-e/ QTp ratio in occupationally exposed workers during night hours was significantly lower than during daily activity what was not the case in control persons. Occupational exposure to lead do not change significantly the transmural dispersion of repolarization. Occupational exposure to lead diminishes the QTp-e/QTp ratio during the night.

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

    Science.gov (United States)

    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.

  14. Lead concentrations and risk exposure assessment in surface soils ...

    African Journals Online (AJOL)

    This study investigated lead concentrations in < 250 μm and < 75 μm of deposited dust and< 2000 μm, < 250 μm, and < 75 μm of surface soils at undeveloped residential lands leased to auto-mechanic artisans for a minimum of ten years and estimated exposure risk for children that will reside on the polluted lands after the ...

  15. Lack of observed movement response to lead exposure of California condors

    Science.gov (United States)

    Poessel, Sharon; Brandt, Joseph; Uyeda, Linda; Astell, Molly; Katzner, Todd E.

    2018-01-01

    Lead poisoning is an important conservation concern for wildlife, and scavenging birds are especially at risk from consumption of carcasses of animals killed with lead ammunition. Because current methods to identify lead exposure require animal capture and blood collection, management would benefit from the development of a less costly and noninvasive behavioral test for illness in wild animals. We attempted to design such a test to identify lead exposure in California condors (Gymnogyps californianus) that we tracked with global positioning system (GPS) telemetry in southern California, USA, 2013–2016. We measured blood-lead concentrations in tracked birds and expected that flight behavior would be influenced by lead exposure; thus, we measured the effect of blood-lead concentrations on 2 different types of movement rates and on the proportion of time condors spent in flight. We found no effect of lead exposure on any of these 3 behavioral metrics. Our work suggests that the measurements we took of flight behaviors were not a useful tool in predicting lead exposure in the mildly to moderately exposed birds we studied. Wild birds are effective at hiding illness, especially condors who have a strong social hierarchy in which showing weakness is a disadvantage. However, focusing on behaviors other than flight, expanding the sample studied to include birds with a wider range of lead concentration values, or analyzing tissues such as feathers (rather than, or in addition to, blood) may be more useful for identification of lead exposure and other diseases that may limit wildlife populations. © 2017 This article is a U.S. Government work and is in the public domain in the USA.

  16. Current leads cooling for the series-connected hybrid magnets

    Science.gov (United States)

    Bai, Hongyu; Marshall, William S.; Bird, Mark D.; Gavrilin, Andrew V.; Weijers, Hubertus W.

    2014-01-01

    Two Series-Connected Hybrid (SCH) magnets are being developed at the National High Magnetic Field Laboratory. Both SCH magnets combine a set of resistive Florida-Bitter coils with a superconducting outsert coil constructed of the cable-in-conduit conductor (CICC). The outsert coils of the two magnets employ 20 kA BSCCO HTS current leads for the power supply although they have different designs and cooling methods. The copper heat exchangers of the HTS current leads for the HZB SCH are cooled with forced flow helium at a supply temperature of 44 K, while the copper heat exchangers of HTS current leads for NHMFL SCH are cooled with liquid nitrogen at a temperature of 78 K in a self-demand boil-off mode. This paper presents the two cooling methods and their impacts on cryogenic systems. Their efficiencies and costs are compared and presented.

  17. Two cases of acute lead poisoning due to occupational exposure to lead.

    Science.gov (United States)

    Ogawa, Masanori; Nakajima, Yoshiaki; Kubota, Ryuichi; Endo, Yoko

    2008-04-01

    We experienced two cases of acute lead poisoning due to occupational exposure to lead. The patients were engaged in stripping off antirust compounds including Pb from a bridge and re-painting it at the same work place. Both patients exhibited colic, arthralgia, and anemia. Blood lead levels were 73.1 microg/dl and 96.3 microg/dl. Intravenous CaEDTA chelation therapy was therefore performed. After chelation, blood lead levels decreased and symptoms gradually disappeared. Although the patients were working with protective equipment, the workplace was in the mountains and there was no water for washing. The patients were thus unable to washing their hands and faces. We assume that they swallowed lead dust left on their hands and faces when they removed their clothing, and believe that this poisoning occurred due to lack of knowledge sufficient for protection.

  18. Behavior of active deposit of lead (Teisinger) in the Japanese free from occupational exposure to lead

    Energy Technology Data Exchange (ETDEWEB)

    Araki, S

    1973-12-01

    Intravenous infusion of calcium disodium ethylenediamine tetraacetate (CaEDTA) was given to 45 Japanese adults without occupational exposure to lead for 1 hr at a dosage of 20 mg/kg body weight in 250 ml of 5 percent glucose solution. The urinary excretion of lead was estimated for 24 hr before, and for 2 hr and 24 hr after the administration. The least variation of the lead content was recognized in the 24-hour urinary excretion after the injection of CaEDTA. No sexual difference was noted in the creatinine-corrected lead concentration. By multiple linear regression and correlation analyses, age was found to be significant in determining positively the lead level mobilized in 24-hour urine samples. Height was significant in determining positively the spontaneous 24-hour urinary lead excretion. Certain significant correlations existed among lead in blood, delta-aminolevulinic acid dehydratase in erythrocytes, delta-aminolevulinic acid in urine, coproporphyrin in urine, lead in urine, and lead mobilized by CaEDTA. The existence of active body burden of lead was suggested in human subjects under usual urban conditions where the total ambient lead concentration averaged 1.7 micrograms/cm m of air. Based on a few assumptions, it was calculated that about 3 micrograms of lead was retained on the average per day by a Japanese adult. Daily retention of lead by Japanese adults was formularized as lead in micrograms equals a constant (K) times daily creatinine excretion in grams, where K is 1.77 in men and 2.73 in women. (Air Pollut. Abstr.)

  19. Air pollution and heart rate variability: effect modification by chronic lead exposure.

    Science.gov (United States)

    Park, Sung Kyun; O'Neill, Marie S; Vokonas, Pantel S; Sparrow, David; Wright, Robert O; Coull, Brent; Nie, Huiling; Hu, Howard; Schwartz, Joel

    2008-01-01

    Outdoor air pollution and lead exposure can disturb cardiac autonomic function, but the effects of both these exposures together have not been studied. We examined whether higher cumulative lead exposures, as measured by bone lead, modified cross-sectional associations between air pollution and heart rate variability among 384 elderly men from the Normative Aging Study. We used linear regression, controlling for clinical, demographic, and environmental covariates. We found graded, significant reductions in both high-frequency and low-frequency powers of heart rate variability in relation to ozone and sulfate across the quartiles of tibia lead. Interquartile range increases in ozone and sulfate were associated respectively, with 38% decrease (95% confidence interval = -54.6% to -14.9%) and 22% decrease (-40.4% to 1.6%) in high frequency, and 38% decrease (-51.9% to -20.4%) and 12% decrease (-28.6% to 9.3%) in low frequency, in the highest quartile of tibia lead after controlling for potential confounders. We observed similar but weaker effect modification by tibia lead adjusted for education and cumulative traffic (residuals of the regression of tibia lead on education and cumulative traffic). Patella lead modified only the ozone effect on heart rate variability. People with long-term exposure to higher levels of lead may be more sensitive to cardiac autonomic dysfunction on high air pollution days. Efforts to understand how environmental exposures affect the health of an aging population should consider both current levels of pollution and history of lead exposure as susceptibility factors.

  20. Formal recycling of e-waste leads to increased exposure to toxic metals: an occupational exposure study from Sweden.

    Science.gov (United States)

    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.

  1. Lead exposure of the child population in Greece.

    Science.gov (United States)

    Maravelias, C; Athanaselis, S; Poulos, L; Alevisopoulos, G; Ewers, U; Koutselinis, A

    1994-12-18

    Lead exposure of the child population was studied in three different areas in Greece: Kalamata which is a rural area of Southern Greece; Tavros, a district of Athens with a considerable industrial activity; and Lavrion, a small city near Athens where a lead-zinc mining and smelting industrial complex has existed for more than 90 years. The results were evaluated with respect to a number of individual, social and environmental variables (i.e. smelter, occupation of the father) especially those concerning the area of Lavrion which is the most heavily polluted area in Greece. The results of this study can be considered as an index for the extent of the lead pollution problem in the named areas of Greece.

  2. Current practices in generation of small molecule new leads.

    Science.gov (United States)

    Goodnow, R A

    2001-01-01

    The current drug discovery processes in many pharmaceutical companies require large and growing collections of high quality lead structures for use in high throughput screening assays. Collections of small molecules with diverse structures and "drug-like" properties have, in the past, been acquired by several means: by archive of previous internal lead optimization efforts, by purchase from compound vendors, and by union of separate collections following company mergers. More recently, many drug discovery companies have established dedicated efforts to effect synthesis by internal and/or outsourcing efforts of targeted compound libraries for new lead generation. Although high throughput/combinatorial chemistry is an important component in the process of new lead generation, the selection of library designs for synthesis and the subsequent design of library members has evolved to a new level of challenge and importance. The potential benefits of screening multiple small molecule compound library designs against multiple biological targets offers substantial opportunity to discover new lead structures. Subsequent optimization of such compounds is often accelerated because of the structure-activity relationship (SAR) information encoded in these lead generation libraries. Lead optimization is often facilitated due to the ready applicability of high-throughput chemistry (HTC) methods for follow-up synthesis. Some of the strategies, trends, and critical issues central to the success of lead generation processes are discussed below. Copyright 2002 Wiley-Liss, Inc.

  3. Sex-based differences in gene expression in hippocampus following postnatal lead exposure

    International Nuclear Information System (INIS)

    Schneider, J.S.; Anderson, D.W.; Sonnenahalli, H.; Vadigepalli, R.

    2011-01-01

    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. - 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.

  4. Testing and evaluation of high temperature superconductor current leads

    International Nuclear Information System (INIS)

    Yadav, Anand; Puntambekar, Avinash; Manekar, M.A.

    2009-01-01

    National Institute for Inter-disciplinary Science and Technology (NIIST), Council of Scientific and Industrial Research, Trivandrum (formerly Regional Research Laboratory) has accomplished a DAE-BRNS project with Raja Ramanna Centre for Advanced Technology (RRCAT) as principal collaborator for the development of high temperature superconductor (HTS) current leads. These HTS current leads have self-field critical currents (Ic) ranging from 50 A to 1000 A at liquid nitrogen (LN 2 ) temperature. These HTS are made out of silver sheathed Bismuth Strontium Calcium Copper Oxide (BSCCO-2223), for direct application in superconducting (SC) systems involving transportation of high electric currents from power sources at room temperature to superconducting devices at cryogenic temperatures. RRCAT has participated in this project by testing and evaluation of these HTS current leads and carried out actual load trials. In this paper, we will describe the HTS testing setup, tests performed with their testing procedure and the test results. The testing of these HTS has been done with joint effort of Materials Advanced Accelerator Science and Cryogenics Div. and Superconducting Technology Lab (SCT Lab), Advanced Accelerator Module Development Div., using the test facility available at the SCT Lab. (author)

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

    Science.gov (United States)

    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.

  6. Lead content of dried films of domestic paints currently sold in Nigeria

    International Nuclear Information System (INIS)

    Adebamowo, Eugenious O.; Scott Clark, C.; Roda, Sandy; Agbede, Oluwole A.; Sridhar, Mynepalli K.C.; Adebamowo, Clement A.

    2007-01-01

    Children are at higher risk from lead exposure because their developing neural system is susceptible to its neurotoxic effects. We studied lead levels of paints manufactured in Nigeria in 2006. Lead levels in 5 colors of paints, each from different manufacturers were measured using flame-atomic absorption spectroscopy. We found that 96% of the paints had higher than recommended levels of lead. The mean lead level of paints ranged from 84.8 to 50,000 ppm, with mean of 14,500 ppm and median of 15,800 ppm. The main determinant of lead levels was color of the paint. As lead levels in paint sold in the past years in Nigeria are likely to be at least as high as that currently sold, it is likely that many existing houses contain dangerously high levels of lead. Efforts need to be undertaken to assess the presence of high lead levels in existing housing and if detected, intervention programs for eliminating risk of exposure should be developed in addition to measures to increase awareness and enforce regulations leading to the elimination of lead based domestic paint

  7. The Feasibility of Using Lead in Hair Concentration in Monitoring Environmental Exposure in Children

    NARCIS (Netherlands)

    Wibowo, A.A.E.; Brunekreef, B.; Lebret, E.; Pieters, H.

    1980-01-01

    The feasibility of lead in hair as an indicator of lead exposure has been compared to that of lead in blood and zinc protoporphyrin in blood levels in 1-3 year-old children living within 1 km of a lead smelter. Lead exposure was measured as lead in house dust, outdoor and indoor lead in air

  8. Engineering design of a high-temperature superconductor current lead

    International Nuclear Information System (INIS)

    Niemann, R.C.; Cha, Y.S.; Hull, J.R.; Daugherty, M.A.; Buckles, W.E.

    1993-01-01

    As part of the US Department of Energy's Superconductivity Pilot Center Program, Argonne National Laboratory and Superconductivity, Inc., are developing high-temperature superconductor (HTS) current leads suitable for application to superconducting magnetic energy storage systems. The principal objective of the development program is to design, construct, and evaluate the performance of HTS current leads suitable for near-term applications. Supporting objectives are to (1) develop performance criteria; (2) develop a detailed design; (3) analyze performance; (4) gain manufacturing experience in the areas of materials and components procurement, fabrication and assembly, quality assurance, and cost; (5) measure performance of critical components and the overall assembly; (6) identify design uncertainties and develop a program for their study; and (7) develop application-acceptance criteria

  9. Engineering design of a high-temperature superconductor current lead

    Science.gov (United States)

    Niemann, R. C.; Cha, Y. S.; Hull, J. R.; Daugherty, M. A.; Buckles, W. E.

    As part of the US Department of Energy's Superconductivity Pilot Center Program, Argonne National Laboratory and Superconductivity, Inc., are developing high-temperature superconductor (HTS) current leads suitable for application to superconducting magnetic energy storage systems. The principal objective of the development program is to design, construct, and evaluate the performance of HTS current leads suitable for near-term applications. Supporting objectives are to (1) develop performance criteria; (2) develop a detailed design; (3) analyze performance; (4) gain manufacturing experience in the areas of materials and components procurement, fabrication and assembly, quality assurance, and cost; (5) measure performance of critical components and the overall assembly; (6) identify design uncertainties and develop a program for their study; and (7) develop application-acceptance criteria.

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

    Science.gov (United States)

    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 (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. Copyright © 2011 Elsevier B.V. All rights reserved.

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

    International Nuclear Information System (INIS)

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

    2013-01-01

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

    Energy Technology Data Exchange (ETDEWEB)

    Hinwood, A.L., E-mail: a.hinwood@ecu.edu.au [Centre for Ecosystem Management, Edith Cowan University, 270 Joondalup Drive, Joondalup, WA 6027 (Australia); Callan, A. C.; Ramalingam, M.; Boyce, M. [Centre for Ecosystem Management, Edith Cowan University, 270 Joondalup Drive, Joondalup, WA 6027 (Australia); Heyworth, J. [School Population Health, The University of Western Australia, 35 Stirling Highway Crawley, WA 6009 (Australia); McCafferty, P. [ChemCentre, PO Box 1250, Bentley, WA 6983 (Australia); Odland, J. Ø. [Department of Community Medicine, University of Tromsø, N-9037 Tromsø (Norway)

    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

  13. Survey of current lead use, handling, hygiene, and contaminant controls among New Jersey industries.

    Science.gov (United States)

    Blando, James D; Lefkowitz, Daniel K; Valiante, David; Gerwel, Barbara; Bresnitz, Eddy

    2007-08-01

    In 2003, a chemical handling and use survey was mailed to New Jersey employers identified as currently using lead in their industrial processes. This survey was used to ascertain characteristics about lead use, handling, and protection of employees during manufacturing operations. The survey included a diverse group of current lead users with a total lead use range from less than 1 pound to more than 63 million pounds of lead per year. The survey allowed for a comprehensive characterization of hazards and protective measures associated with this metal, still commonly used in many products and industrial processes. Forty-five surveys were returned by companies that are listed in the New Jersey Adult Blood Lead Registry, which is part of the New Jersey Adult Blood Lead Epidemiology and Surveillance (ABLES) program. This program records and investigates cases of adults with greater than 25 mu g/dL of lead in their blood; most cases are related to occupational exposures. This survey found that greater than 25% of these surveyed companies with significant potential for lead exposure did not employ commonly used and basic industrial hygiene practices. In addition, the survey found that 24% of these companies had not conducted air sampling within the last 3 years. Air sampling is the primary trigger for compliance with the Occupational Safety and Health Administration (OSHA) general industry lead standard. Only 17% of the companies have ever been cited for a violation of the OSHA lead standard, and only 46% of these companies have ever had an OSHA inspection. State-based surveillance can be a useful tool for OSHA enforcement activities. Elevated blood lead values in adults should be considered as a trigger for required compliance with an OSHA general industry lead standard.

  14. An evaluation of airborne nickel, zinc, and lead exposure at hot dip galvanizing plants.

    Science.gov (United States)

    Verma, D K; Shaw, D S

    1991-12-01

    Industrial hygiene surveys were conducted at three hot dip galvanizing plants to determine occupational exposure to nickel, zinc, and lead. All three plants employed the "dry process" and used 2% nickel, by weight, in their zinc baths. A total of 32 personal and area air samples were taken. The air samples were analyzed for nickel, zinc, and lead. Some samples were also analyzed for various species of nickel (i.e., metallic, soluble, and oxidic). The airborne concentrations observed for nickel and its three species, zinc, and lead at the three plants were all well below the current and proposed threshold limit values recommended by the American Conference of Governmental Industrial Hygienists (ACGIH).

  15. Current exposure method for CCP’s under Basel III

    Directory of Open Access Journals (Sweden)

    Antonie Kotzé

    2013-04-01

    Full Text Available Exposure-at-default is one of the most interesting and most difficult parameters to estimate in counterparty credit risk. Basel I offered only the non-internal Current Exposure Method for estimating this quantity whilst Basel II further introduced the Standardized Method and an Internal Model Method. Under new Basel III rules a central counterparty is defined as being a financial institution. New principles set out by the Basel Committee on Banking Supervision forces Central Counterparties in using the Current Exposure Method when estimating the credit exposures to Clearing Member banks notwithstanding its shortcomings. The Current Exposure Method relies on the Value-at-Risk methodology and its characteristics are discussed in this note. We will particularly investigate exposures to SAFCOM, the South African clearing house and point to a mathematical discrepancy on how netting is effected through the Basel accord.

  16. An international pooled analysis for obtaining a benchmark dose for environmental lead exposure in children

    DEFF Research Database (Denmark)

    Budtz-Jørgensen, Esben; Bellinger, David; Lanphear, Bruce

    2013-01-01

    Lead is a recognized neurotoxicant, but estimating effects at the lowest measurable levels is difficult. An international pooled analysis of data from seven cohort studies reported an inverse and supra-linear relationship between blood lead concentrations and IQ scores in children. The lack...... of a clear threshold presents a challenge to the identification of an acceptable level of exposure. The benchmark dose (BMD) is defined as the dose that leads to a specific known loss. As an alternative to elusive thresholds, the BMD is being used increasingly by regulatory authorities. Using the pooled data...... yielding lower confidence limits (BMDLs) of about 0.1-1.0 μ g/dL for the dose leading to a loss of one IQ point. We conclude that current allowable blood lead concentrations need to be lowered and further prevention efforts are needed to protect children from lead toxicity....

  17. Characterizing Golden Eagle risk to lead and anticoagulant rodenticide exposure: A review

    Science.gov (United States)

    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.

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

    International Nuclear Information System (INIS)

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

    2010-01-01

    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 48 μg/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

  19. Adverse health effects of lead exposure on children and exploration to internal lead indicator

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Q.; Zhao, H.H. [Department of Epidemiology and Biostatistics, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030 (China); Chen, J.W.; Gu, K.D.; Zhang, Y.Z.; Zhu, Y.X.; Zhou, Y.K. [Minitry of Environmental Protection Key Lab of Environment, Wuhan 430030 (China); Ye, L.X., E-mail: yelx2004@163.com [Department of Epidemiology and Biostatistics, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030 (China)

    2009-11-15

    Our research on adverse effects of lead exposures on physical and neurobehavioral health of children aged 6-12 years in 4 villages, labeled as K, M, L, and X, in rural China, was reported in this article. Lead in blood (PbB), urine (PbU), hairs (PbH), and nails (PbN) were measured by graphite furnace atomic absorption spectrometry. Abbreviated Symptom Questionnaire of Conner's instruments and Revised Raven's Standard Progressive Matrices were applied to evaluate childhood attention deficit/hyperactivity disorders (ADHD) and intelligences. Geometric means (SD) of PbB, PbU, PbH and PbN concentrations were 71.2 {mu}g/L (1.56), 11.7 {mu}g/g (1.75), 12.5 {mu}g/g (2.82), and 25.3 {mu}g/g (2.79), respectively. 54 (17.0%) children had PbB levels of {>=} 100 {mu}g/L. Boys, the 6-10 years old, and living in village K were 2.11, 2.48, and 9.16 times, respectively, more likely to be poisoned by lead than girls, aged 11-12 years, and residing in X. 18 (5.7%) and 37 (11.7%) subjects had ADHD and mental retardations, respectively. Inverse relationships between intelligences and natural log transformed PbU and PbH levels were observed with respective odds ratios (95%CI) of 1.79 (1.00-3.22) and 1.46 (1.06-2.03) or 1.28 (1.04-1.58) and 1.73 (1.18-2.52) by binary or ordinal logistic regression modeling. ADHD prevalence was different by gender and age of subjects. PbU, PbH, and PbN related to PbB positively with respective correlation coefficients of 0.530, 0.477, and 0.181. Receiver operating characteristic (ROC) curves of the three measurements reveled areas under curves (AUCs) being 0.829, 0.758, and 0.687, respectively. In conclusion, children had moderate levels of lead exposures in this rural area. Intelligence declines were associated with internal lead levels among children. ROC analysis suggests PbU an internal lead indicator close to PbB.

  20. Adverse health effects of lead exposure on children and exploration to internal lead indicator

    International Nuclear Information System (INIS)

    Wang, Q.; Zhao, H.H.; Chen, J.W.; Gu, K.D.; Zhang, Y.Z.; Zhu, Y.X.; Zhou, Y.K.; Ye, L.X.

    2009-01-01

    Our research on adverse effects of lead exposures on physical and neurobehavioral health of children aged 6-12 years in 4 villages, labeled as K, M, L, and X, in rural China, was reported in this article. Lead in blood (PbB), urine (PbU), hairs (PbH), and nails (PbN) were measured by graphite furnace atomic absorption spectrometry. Abbreviated Symptom Questionnaire of Conner's instruments and Revised Raven's Standard Progressive Matrices were applied to evaluate childhood attention deficit/hyperactivity disorders (ADHD) and intelligences. Geometric means (SD) of PbB, PbU, PbH and PbN concentrations were 71.2 μg/L (1.56), 11.7 μg/g (1.75), 12.5 μg/g (2.82), and 25.3 μg/g (2.79), respectively. 54 (17.0%) children had PbB levels of ≥ 100 μg/L. Boys, the 6-10 years old, and living in village K were 2.11, 2.48, and 9.16 times, respectively, more likely to be poisoned by lead than girls, aged 11-12 years, and residing in X. 18 (5.7%) and 37 (11.7%) subjects had ADHD and mental retardations, respectively. Inverse relationships between intelligences and natural log transformed PbU and PbH levels were observed with respective odds ratios (95%CI) of 1.79 (1.00-3.22) and 1.46 (1.06-2.03) or 1.28 (1.04-1.58) and 1.73 (1.18-2.52) by binary or ordinal logistic regression modeling. ADHD prevalence was different by gender and age of subjects. PbU, PbH, and PbN related to PbB positively with respective correlation coefficients of 0.530, 0.477, and 0.181. Receiver operating characteristic (ROC) curves of the three measurements reveled areas under curves (AUCs) being 0.829, 0.758, and 0.687, respectively. In conclusion, children had moderate levels of lead exposures in this rural area. Intelligence declines were associated with internal lead levels among children. ROC analysis suggests PbU an internal lead indicator close to PbB.

  1. Adverse health effects of lead exposure on children and exploration to internal lead indicator

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Q.; Zhao, H. H. [Department of Epidemiology and Biostatistics, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030 (China); Chen, J. W.; Gu, K. D.; Zhang, Y. Z.; Zhu, Y. X.; Zhou, Y. K. [Minitry of Environmental Protection Key Lab of Environment, Wuhan 430030 (China); Ye, L.X., E-mail: yelx2004@163.com [Department of Epidemiology and Biostatistics, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030 (China)

    2009-11-15

    Our research on adverse effects of lead exposures on physical and neurobehavioral health of children aged 6-12 years in 4 villages, labeled as K, M, L, and X, in rural China, was reported in this article. Lead in blood (PbB), urine (PbU), hairs (PbH), and nails (PbN) were measured by graphite furnace atomic absorption spectrometry. Abbreviated Symptom Questionnaire of Conner's instruments and Revised Raven's Standard Progressive Matrices were applied to evaluate childhood attention deficit/hyperactivity disorders (ADHD) and intelligences. Geometric means (SD) of PbB, PbU, PbH and PbN concentrations were 71.2 {mu}g/L (1.56), 11.7 {mu}g/g (1.75), 12.5 {mu}g/g (2.82), and 25.3 {mu}g/g (2.79), respectively. 54 (17.0%) children had PbB levels of {>=} 100 {mu}g/L. Boys, the 6-10 years old, and living in village K were 2.11, 2.48, and 9.16 times, respectively, more likely to be poisoned by lead than girls, aged 11-12 years, and residing in X. 18 (5.7%) and 37 (11.7%) subjects had ADHD and mental retardations, respectively. Inverse relationships between intelligences and natural log transformed PbU and PbH levels were observed with respective odds ratios (95%CI) of 1.79 (1.00-3.22) and 1.46 (1.06-2.03) or 1.28 (1.04-1.58) and 1.73 (1.18-2.52) by binary or ordinal logistic regression modeling. ADHD prevalence was different by gender and age of subjects. PbU, PbH, and PbN related to PbB positively with respective correlation coefficients of 0.530, 0.477, and 0.181. Receiver operating characteristic (ROC) curves of the three measurements reveled areas under curves (AUCs) being 0.829, 0.758, and 0.687, respectively. In conclusion, children had moderate levels of lead exposures in this rural area. Intelligence declines were associated with internal lead levels among children. ROC analysis suggests PbU an internal lead indicator close to PbB.

  2. {beta}-adrenergic receptor density and adenylate cyclase activity in lead-exposed rat brain after cessation of lead exposure

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Huoy-Rou [I-Shou University, Department of Biomedical Engineering, Dashu Shiang, Kaohsiung County (Taiwan); Tsao, Der-An [Fooyin University of Technology, Department of Medical Technology (Taiwan); Yu, Hsin-Su [Taiwan University, Department of Dermatology, College of Medicine (Taiwan); Ho, Chi-Kung [Kaohsiung Medical University, Occupational Medicine (Taiwan); Kaohsiung Medical University, Graduate Institute of Medicine, Research Center for Occupational Disease (Taiwan)

    2005-01-01

    To understanding the reversible or irreversible harm to the {beta}-adrenergic system in the brain of lead-exposed rats, this study sets up an animal model to estimate the change in the sympathetic nervous system of brain after lead exposure was withdrawn. We address the following topics in this study: (a) the relationship between withdrawal time of lead exposure and brain {beta}-adrenergic receptor, blood lead level, and brain lead level in lead-exposed rats after lead exposure was stopped; and (b) the relationship between lead level and {beta}-adrenergic receptor and cyclic AMP (c-AMP) in brain. Wistar rats were chronically fed with 2% lead acetate and water for 2 months. Radioligand binding was assayed by a method that fulfilled strict criteria of {beta}-adrenergic receptor using the ligand [{sup 125}I]iodocyanopindolol. The levels of lead were determined by electrothermal atomic absorption spectrometry. The c-AMP level was determined by radioimmunoassay. The results showed a close relationship between decreasing lead levels and increasing numbers of brain {beta}-adrenergic receptors and brain adenylate cyclase activity after lead exposure was withdrawn. The effect of lead exposure on the {beta}-adrenergic system of the brain is a partly reversible condition. (orig.)

  3. Characterization of high-current, high-temperature superconductor current lead elements

    International Nuclear Information System (INIS)

    Niemann, R.C.; Evans, D.J.; Fisher, B.L.; Brockenborough, W.E.; Roberts, P.R.; Rodenbush, A.J.

    1996-08-01

    The refrigeration loads of current leads for superconducting magnets can be significantly reduced by using high-temperature superconductor (HTS) leads. An HTS conductor type that is well suited for this application is a laminated sintered stack of HTS powder-in-tube (PIT) tapes. The superconducting elements are normally characterized by their manufacturer by measuring critical currents at 77 K in self field. Additional characterization, which correlates electrical performance at 77 K and at lower temperatures with applied magnetic fields, provides the current lead designer and conductor element manufacturer with critical information. For HTS conductor elements comprising a laminated and sintered stack of Bi-2223 PIT tapes having an alloyed Ag sheath, this characterization uses variable applied fields and operating temperatures

  4. Identification of sources of lead exposure in French children by lead isotope analysis: a cross-sectional study

    Directory of Open Access Journals (Sweden)

    Lucas Jean-Paul

    2011-08-01

    Full Text Available Abstract Background The amount of lead in the environment has decreased significantly in recent years, and so did exposure. However, there is no known safe exposure level and, therefore, the exposure of children to lead, although low, remains a major public health issue. With the lower levels of exposure, it is becoming more difficult to identify lead sources and new approaches may be required for preventive action. This study assessed the usefulness of lead isotope ratios for identifying sources of lead using data from a nationwide sample of French children aged from six months to six years with blood lead levels ≥25 μg/L. Methods Blood samples were taken from 125 children, representing about 600,000 French children; environmental samples were taken from their homes and personal information was collected. Lead isotope ratios were determined using quadrupole ICP-MS (inductively coupled plasma - mass spectrometry and the isotopic signatures of potential sources of exposure were matched with those of blood in order to identify the most likely sources. Results In addition to the interpretation of lead concentrations, lead isotope ratios were potentially of use for 57% of children aged from six months to six years with blood lead level ≥ 25 μg/L (7% of overall children in France, about 332,000 children, with at least one potential source of lead and sufficiently well discriminated lead isotope ratios. Lead isotope ratios revealed a single suspected source of exposure for 32% of the subjects and were able to eliminate at least one unlikely source of exposure for 30% of the children. Conclusions In France, lead isotope ratios could provide valuable additional information in about a third of routine environmental investigations.

  5. Current perspectives in fragment-based lead discovery (FBLD)

    Science.gov (United States)

    Lamoree, Bas; Hubbard, Roderick E.

    2017-01-01

    It is over 20 years since the first fragment-based discovery projects were disclosed. The methods are now mature for most ‘conventional’ targets in drug discovery such as enzymes (kinases and proteases) but there has also been growing success on more challenging targets, such as disruption of protein–protein interactions. The main application is to identify tractable chemical startpoints that non-covalently modulate the activity of a biological molecule. In this essay, we overview current practice in the methods and discuss how they have had an impact in lead discovery – generating a large number of fragment-derived compounds that are in clinical trials and two medicines treating patients. In addition, we discuss some of the more recent applications of the methods in chemical biology – providing chemical tools to investigate biological molecules, mechanisms and systems. PMID:29118093

  6. Lead Exposure: A Summary of Global Studies and the Need for New Studies from Saudi Arabia

    Directory of Open Access Journals (Sweden)

    A. P. Shaik

    2014-01-01

    Full Text Available Lead poisoning (plumbism can cause irreversible genetic and reproductive toxicity, hematological effects, neurological damage, and cardiovascular effects. Despite many efforts to minimize lead poisoning, it continues to be a major health concern in many developing and developed countries. Despite efforts to control lead exposure and toxicity, serious cases of lead poisoning increasingly occur as a result of higher vehicular traffic and industrialization. The biomarkers for identification of genetic susceptibility to a particular disease are useful to identify individuals who are at risk for lead poisoning. Although many such studies have been taken up elsewhere, very few studies were performed in Saudi Arabia to assess susceptibility to lead poisoning. This indicates an urgent need for testing of susceptible individuals. The present paper was planned to understand the genetic susceptibility to lead toxicity in the various population studies conducted worldwide and also to correlate it with the current scenario in Saudi Arabia. Such studies are necessary for appropriate precautions in terms of diet and avoiding exposure to be used in order to prevent adverse health effects.

  7. Sex-Dependent Effects of Developmental Lead Exposure on the Brain

    Science.gov (United States)

    Singh, Garima; Singh, Vikrant; Sobolewski, Marissa; Cory-Slechta, Deborah A.; Schneider, Jay S.

    2018-01-01

    The role of sex as an effect modifier of developmental lead (Pb) exposure has until recently received little attention. Lead exposure in early life can affect brain development with persisting influences on cognitive and behavioral functioning, as well as, elevated risks for developing a variety of diseases and disorders in later life. Although both sexes are affected by Pb exposure, the incidence, manifestation, and severity of outcomes appears to differ in males and females. Results from epidemiologic and animal studies indicate significant effect modification by sex, however, the results are not consistent across studies. Unfortunately, only a limited number of human epidemiological studies have included both sexes in independent outcome analyses limiting our ability to draw definitive conclusions regarding sex-differentiated outcomes. Additionally, due to various methodological differences across studies, there is still not a good mechanistic understanding of the molecular effects of lead on the brain and the factors that influence differential responses to Pb based on sex. In this review, focused on prenatal and postnatal Pb exposures in humans and animal models, we discuss current literature supporting sex differences in outcomes in response to Pb exposure and explore some of the ideas regarding potential molecular mechanisms that may contribute to sex-related differences in outcomes from developmental Pb exposure. The sex-dependent variability in outcomes from developmental Pb exposure may arise from a combination of complex factors, including, but not limited to, intrinsic sex-specific molecular/genetic mechanisms and external risk factors including sex-specific responses to environmental stressors which may act through shared epigenetic pathways to influence the genome and behavioral output. PMID:29662502

  8. Sex-Dependent Effects of Developmental Lead Exposure on the Brain

    Directory of Open Access Journals (Sweden)

    Garima Singh

    2018-03-01

    Full Text Available The role of sex as an effect modifier of developmental lead (Pb exposure has until recently received little attention. Lead exposure in early life can affect brain development with persisting influences on cognitive and behavioral functioning, as well as, elevated risks for developing a variety of diseases and disorders in later life. Although both sexes are affected by Pb exposure, the incidence, manifestation, and severity of outcomes appears to differ in males and females. Results from epidemiologic and animal studies indicate significant effect modification by sex, however, the results are not consistent across studies. Unfortunately, only a limited number of human epidemiological studies have included both sexes in independent outcome analyses limiting our ability to draw definitive conclusions regarding sex-differentiated outcomes. Additionally, due to various methodological differences across studies, there is still not a good mechanistic understanding of the molecular effects of lead on the brain and the factors that influence differential responses to Pb based on sex. In this review, focused on prenatal and postnatal Pb exposures in humans and animal models, we discuss current literature supporting sex differences in outcomes in response to Pb exposure and explore some of the ideas regarding potential molecular mechanisms that may contribute to sex-related differences in outcomes from developmental Pb exposure. The sex-dependent variability in outcomes from developmental Pb exposure may arise from a combination of complex factors, including, but not limited to, intrinsic sex-specific molecular/genetic mechanisms and external risk factors including sex-specific responses to environmental stressors which may act through shared epigenetic pathways to influence the genome and behavioral output.

  9. Lead exposure biomarkers and mini-mental status exam scores in older men

    NARCIS (Netherlands)

    Wright, RO; Tsaih, SW; Schwartz, J; Spiro, A; McDonald, K; Weiss, ST; Hu, H

    2003-01-01

    Background: Lead is neurotoxic; yet, whether cognitive decline in older persons is associated with lead exposure is unknown. We studied whether lead exposure biomarkers are associated with cognitive test scores, as well as the modifying effects of age on the lead-cognition relationship. Methods:

  10. Lead exposure biomarkers and mini-mental status exam scores in older men

    NARCIS (Netherlands)

    Wright, RO; Tsaih, SW; Schwartz, J; Spiro, A; McDonald, K; Weiss, ST; Hu, H

    Background: Lead is neurotoxic; yet, whether cognitive decline in older persons is associated with lead exposure is unknown. We studied whether lead exposure biomarkers are associated with cognitive test scores, as well as the modifying effects of age on the lead-cognition relationship. Methods:

  11. Lead, mercury, and cadmium exposure and attention deficit hyperactivity disorder in children

    International Nuclear Information System (INIS)

    Kim, Stephani; Arora, Monica; Fernandez, Cristina; Landero, Julio; Caruso, Joseph; Chen, Aimin

    2013-01-01

    Background: There is limited research examining the relationship between lead (Pb) exposure and medically diagnosed attention deficit hyperactivity disorder (ADHD) in children. The role of mercury (Hg) and cadmium (Cd) exposures in ADHD development is even less clear. Objectives: To examine the relationship between Pb, Hg, and Cd and ADHD in children living inside and outside a Lead Investigation Area (LIA) of a former lead refinery in Omaha, NE. Methods: We carried out a case-control study with 71 currently medically diagnosed ADHD cases and 58 controls from a psychiatric clinic and a pediatric clinic inside and outside of the LIA. The participants were matched on age group (5–8, 9–12 years), sex, race (African American or Caucasians and others), and location (inside or outside LIA). We measured whole blood Pb, total Hg, and Cd using inductively coupled plasma mass spectrometry. Results: Inside the LIA, the 27 cases had blood Pb geometric mean (GM) 1.89 µg/dL and the 41 controls had 1.51 µg/dL. Outside the LIA, the 44 cases had blood Pb GM 1.02 µg/dL while the 17 controls had 0.97 µg/dL. After adjustment for matching variables and maternal smoking, socioeconomic status, and environmental tobacco exposure, each natural log unit blood Pb had an odds ratio of 2.52 with 95% confidence interval of 1.07–5.92. Stratification by the LIA indicated similar point estimate but wider CIs. No associations were observed for Hg or Cd. Conclusions: Postnatal Pb exposure may be associated with higher risk of clinical ADHD, but not the postnatal exposure to Hg or Cd. -- Highlights: • Blood Pb levels are associated with ADHD diagnosis in children. • No association was found between blood Cd or Hg levels and ADHD. • Children living close to hazardous waste site need to reduce metal exposure

  12. Lead, mercury, and cadmium exposure and attention deficit hyperactivity disorder in children

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Stephani [Division of Epidemiology and Biostatistics, Department of Environmental Health, University of Cincinnati College of Medicine, Cincinnati, OH 45267 (United States); Arora, Monica [Department of Psychiatry, Creighton University School of Medicine, Omaha, NE 68131 (United States); Fernandez, Cristina [Department of Pediatrics, Creighton University School of Medicine, Omaha, NE 68131 (United States); Landero, Julio; Caruso, Joseph [Metallomics Center, Department of Chemistry, University of Cincinnati, Cincinnati, OH 45221 (United States); Chen, Aimin, E-mail: aimin.chen@uc.edu [Division of Epidemiology and Biostatistics, Department of Environmental Health, University of Cincinnati College of Medicine, Cincinnati, OH 45267 (United States)

    2013-10-15

    Background: There is limited research examining the relationship between lead (Pb) exposure and medically diagnosed attention deficit hyperactivity disorder (ADHD) in children. The role of mercury (Hg) and cadmium (Cd) exposures in ADHD development is even less clear. Objectives: To examine the relationship between Pb, Hg, and Cd and ADHD in children living inside and outside a Lead Investigation Area (LIA) of a former lead refinery in Omaha, NE. Methods: We carried out a case-control study with 71 currently medically diagnosed ADHD cases and 58 controls from a psychiatric clinic and a pediatric clinic inside and outside of the LIA. The participants were matched on age group (5–8, 9–12 years), sex, race (African American or Caucasians and others), and location (inside or outside LIA). We measured whole blood Pb, total Hg, and Cd using inductively coupled plasma mass spectrometry. Results: Inside the LIA, the 27 cases had blood Pb geometric mean (GM) 1.89 µg/dL and the 41 controls had 1.51 µg/dL. Outside the LIA, the 44 cases had blood Pb GM 1.02 µg/dL while the 17 controls had 0.97 µg/dL. After adjustment for matching variables and maternal smoking, socioeconomic status, and environmental tobacco exposure, each natural log unit blood Pb had an odds ratio of 2.52 with 95% confidence interval of 1.07–5.92. Stratification by the LIA indicated similar point estimate but wider CIs. No associations were observed for Hg or Cd. Conclusions: Postnatal Pb exposure may be associated with higher risk of clinical ADHD, but not the postnatal exposure to Hg or Cd. -- Highlights: • Blood Pb levels are associated with ADHD diagnosis in children. • No association was found between blood Cd or Hg levels and ADHD. • Children living close to hazardous waste site need to reduce metal exposure.

  13. The relationship between blood lead levels and occupational exposure in a pregnant population

    OpenAIRE

    Osmel La-Llave-León; José Manuel Salas Pacheco; Sergio Estrada Martínez; Eloísa Esquivel Rodríguez; Francisco X. Castellanos Juárez; Ada Sandoval Carrillo; Angélica María Lechuga Quiñones; Fernando Vázquez Alanís; Gonzalo García Vargas; Edna Madai Méndez Hernández; Jaime Duarte Sustaita

    2016-01-01

    Background 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. Methods A cross-sectional stu...

  14. [Lead exposure in the adult population non-occupationally exposed].

    Science.gov (United States)

    Bortoli, A; Mattiello, G

    1983-03-01

    Lead is added into the environment by the production, use and deposited a variety of lead-containing materials. This pollution is increasing during the last years. The major source for the human intake of lead is the food chain. The people who very hardly drinks (especially wine) have been found have very high blood lead levels. 184 hospitalized patients for alcoholic liver diseases were examined and the Pb-B levels were 36,3 +/- 10,2 micrograms/100 ml. Smoking habits are another factor that increases the blood lead levels.

  15. Lead exposure in the adult population non-occupationally exposed

    Energy Technology Data Exchange (ETDEWEB)

    Bortoli, A.; Mattiello, G.

    1983-03-01

    Lead is added into the environment by the production, use and deposited a variety of lead-containing materials. This pollution is increasing during the last years. The major source for the human intake of lead is the food chain. The people who drink heavily (expecially wine) have been found have very high blood lead levels. 184 hospitalized patients for alcoholic liver diseases were examined and the Pb-B levels were 36,3 +/- 10,2 micrograms/100 ml. Smoking habits are another factor that increases the blood lead levels.

  16. Lead, mercury, and cadmium exposure and attention deficit hyperactivity disorder in children.

    Science.gov (United States)

    Kim, Stephani; Arora, Monica; Fernandez, Cristina; Landero, Julio; Caruso, Joseph; Chen, Aimin

    2013-10-01

    There is limited research examining the relationship between lead (Pb) exposure and medically diagnosed attention deficit hyperactivity disorder (ADHD) in children. The role of mercury (Hg) and cadmium (Cd) exposures in ADHD development is even less clear. To examine the relationship between Pb, Hg, and Cd and ADHD in children living inside and outside a Lead Investigation Area (LIA) of a former lead refinery in Omaha, NE. We carried out a case-control study with 71 currently medically diagnosed ADHD cases and 58 controls from a psychiatric clinic and a pediatric clinic inside and outside of the LIA. The participants were matched on age group (5-8, 9-12 years), sex, race (African American or Caucasians and others), and location (inside or outside LIA). We measured whole blood Pb, total Hg, and Cd using inductively coupled plasma mass spectrometry. Inside the LIA, the 27 cases had blood Pb geometric mean (GM) 1.89 µg/dL and the 41 controls had 1.51 µg/dL. Outside the LIA, the 44 cases had blood Pb GM 1.02 µg/dL while the 17 controls had 0.97 µg/dL. After adjustment for matching variables and maternal smoking, socioeconomic status, and environmental tobacco exposure, each natural log unit blood Pb had an odds ratio of 2.52 with 95% confidence interval of 1.07-5.92. Stratification by the LIA indicated similar point estimate but wider CIs. No associations were observed for Hg or Cd. Postnatal Pb exposure may be associated with higher risk of clinical ADHD, but not the postnatal exposure to Hg or Cd. © 2013 Published by Elsevier Inc.

  17. High human exposure to lead through consumption of birds hunted with lead shot

    International Nuclear Information System (INIS)

    Johansen, P.; Asmund, G.; Riget, F.

    2004-01-01

    Lead shot contaminates the edible parts of birds so that tolerable human lead intake is exceeded. - We assess lead contamination of Greenland seabirds killed with lead shot having studied thick-billed murre and common eider, the two most important species in the diet. The lead concentration is very high in meat of eiders killed with lead shot (mean 6.1 μg/g-wet wt, 95% CL 2.1-12). This level is about 44 times higher than in drowned eiders and eight times higher than in shot murres. Analyzing whole breasts instead of sub-samples reveals about seven times higher lead levels in birds' meat. We conclude that in some cases the lead intake by Greenland bird eaters will largely exceed the FAO/WHO tolerable lead intake guideline and that lead shot is a more important source of lead in the diet than previously estimated

  18. Lead exposure and the 2010 achievement test scores of children in New York counties

    Directory of Open Access Journals (Sweden)

    Strayhorn Jillian C

    2012-01-01

    Full Text Available Abstract Background Lead is toxic to cognitive and behavioral functioning in children even at levels well below those producing physical symptoms. Continuing efforts in the U.S. since about the 1970s to reduce lead exposure in children have dramatically reduced the incidence of elevated blood lead levels (with elevated levels defined by the current U.S. Centers for Disease Control threshold of 10 μg/dl. The current study examines how much lead toxicity continues to impair the academic achievement of children of New York State, using 2010 test data. Methods This study relies on three sets of data published for the 57 New York counties outside New York City: school achievement data from the New York State Department of Education, data on incidence of elevated blood lead levels from the New York State Department of Health, and data on income from the U.S. Census Bureau. We studied third grade and eighth grade test scores in English Language Arts and mathematics. Using the county as the unit of analysis, we computed bivariate correlations and regression coefficients, with percent of children achieving at the lowest reported level as the dependent variable and the percent of preschoolers in the county with elevated blood lead levels as the independent variable. Then we repeated those analyses using partial correlations to control for possible confounding effects of family income, and using multiple regressions with income included. Results The bivariate correlations between incidence of elevated lead and number of children in the lowest achievement group ranged between 0.38 and 0.47. The partial correlations ranged from 0.29 to 0.40. The regression coefficients, both bivariate and partial (both estimating the increase in percent of children in the lowest achievement group for every percent increase in the children with elevated blood lead levels, ranged from 0.52 to 1.31. All regression coefficients, when rounded to the nearest integer, were

  19. Effectiveness of lead apron in external exposure reduction

    International Nuclear Information System (INIS)

    Shrikrishna, U.V.; Veerendra, D.D.; Manojkumar, M.; Austine, N.X.; Jadhav, Y.S.; Jashi, K.B.; Bihari, R.R.; Venkataramana, K.

    2006-01-01

    Lead Apron as individual shielding is used primarily in Radiology for protection of personnel against ionizing radiation. Occasionally lead apron of specific design are being used in reactor environment where one-sided radiation fields are encountered. The protection provided by Apron has been evaluated using personnel dosimeter. Based on the results the utility of lead Apron has been discussed in view of ALARA. The paper discusses the results and the recommendations for use in reactor environment. (author)

  20. Lead Free Frangible Ammunition Exposure at United States Air Force Small Arms Firing Ranges, 2005 - 2007

    National Research Council Canada - National Science Library

    Moran, Michael P; Ott, Darrin K

    2008-01-01

    ...) has performed related to health concerns expressed by Security Forces Combat Arms (CATM) instructors regarding exposure to contaminants generated during the discharge of lead free frangible ammunition...

  1. Multimedia Lead Exposure Modeling, and Water Monitoring Perspectives

    Science.gov (United States)

    Drinking water and other sources for lead are the subject of public health concern following the Flint, Michigan drinking water and East Chicago, Indiana lead in soil crises. In 2015, the U.S. EPA’s National Drinking Water Advisory Council recommended establishing a “...

  2. Childhood lead exposure in an enslaved African community in Barbados

    DEFF Research Database (Denmark)

    Schroeder, Hannes; Shuler, Kristrina A.; Chenery, Simon R.

    2013-01-01

    Lead was ubiquitous on Caribbean sugar plantations, where it was used extensively in the production of sugar and rum. Previous studies suggest that skeletal lead contents can be used to identify African-born individuals (as opposed to Creoles) among slave burials found in the New World. To test...... this hypothesis, we measured lead concentrations in enamel samples from 26 individuals from the Newton Plantation cemetery in Barbados, which was in use from around 1660 to 1820, and compared the results with enamel 87Sr/86Sr measurements that had been previously obtained for the same population. Results show...... a clear association between low (i.e., below 1 ppm) enamel lead concentrations and higher enamel 87Sr/86Sr ratios which have previously been interpreted as being indicative of African birth, suggesting that individuals with low enamel lead levels were indeed born in Africa as opposed to the New World...

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

    Directory of Open Access Journals (Sweden)

    Zmirou-Navier Denis

    2011-05-01

    Full Text Available Abstract 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

  4. Current perspectives in HIV post-exposure prophylaxis

    Directory of Open Access Journals (Sweden)

    Sultan B

    2014-10-01

    Full Text Available Binta Sultan,1,2 Paul Benn,1 Laura Waters1 1Department of Genitourinary Medicine, Mortimer Market Centre, Central and North West London NHS Foundation Trust, London, UK; 2Centre for Sexual Health and HIV Research, University College London, London, UK Abstract: The incidence of human immunodeficiency virus (HIV infection continues to rise among core groups and efforts to reduce the numbers of new infections are being redoubled. Post-exposure prophylaxis (PEP is the use of short-term antiretroviral therapy (ART to reduce the risk of acquisition of HIV infection following exposure. Current guidelines recommend a 28-day course of ART within 36–72 hours of exposure to HIV. As long as individuals continue to be exposed to HIV there will be a role for PEP in the foreseeable future. Nonoccupational PEP, the vast majority of which is for sexual exposure (PEPSE, has a significant role to play in HIV prevention efforts. Awareness of PEP and its availability for both clinicians and those who are eligible to receive it are crucial to ensure that PEP is used to its full potential in any HIV prevention strategy. In this review, we provide current evidence for the use of PEPSE, assessment of the risk of HIV transmission, indications for PEP, drug regimens, and management of patients started on PEP. We summarize national and international guidelines for the use of PEPSE. We explore the place of PEP within the wider strategy of reducing HIV incidence rates in the era of treatment as prevention and pre-exposure prophylaxis. We also consider the implications of recent data from interventional and observational studies demonstrating significant reductions in the risk of HIV transmission within a serodiscordant relationship if the HIV-positive partner is taking effective ART upon PEP guidelines. Keywords: post-exposure prophylaxis, pre-exposure prophylaxis, treatment as prevention, human immunodeficiency virus

  5. EPA Leads the Way on Lead Exposure Science and Risk Management

    Science.gov (United States)

    EPA researchers have developed a modeling approach that improves our understanding of the relationship between lead concentrations of various sources (drinking water, soil and dust, food, and air) and children’s blood-lead levels.

  6. Toxicological analysis of the risk of lead exposure in metal processing

    African Journals Online (AJOL)

    concentration and biological lead toxicity markers in blood and urine were performed for both exposed ... biological samples were determined by spectrophotometric methods. Results: The ..... Occupational lead exposure of storage battery.

  7. UV dose-effect relationships and current protection exposure standards

    International Nuclear Information System (INIS)

    Singh, M.S.; Campbell, G.W.

    1982-04-01

    In this paper we have attempted to quantify the health effects in man of uv-radiation exposure of wavelengths from 240 nm to 320 nm. Exposure to uv in this region could result in the formation of skin cancer or premature aging in man. The induction of cancer by uv radiation results from changes in genetic material. We have used the DNA action spectrum coupled with the uv skin cancer data available in the literature to derive the dose-effect relationships. The results are compared against the current uv protection standards

  8. Lead Concentrations and Risk Exposure Assessment in Surface ...

    African Journals Online (AJOL)

    ADOWIE PERE

    µm, < 250 µm, and < 75 µm of surface soils at undeveloped residential lands leased to ... mechanic yards may still be point sources of lead ..... therefore need to conduct a source apportionment ... heavy metals in soil profiles of automobile.

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

    DEFF Research Database (Denmark)

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

    2010-01-01

    , 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......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......–internalconcentration relationships for the direct linkage between lead in environmental media and resultingconcentrations of lead in blood are then presented....

  10. Lead exposure from lead pellets: age-related accumulation in mute swans

    Energy Technology Data Exchange (ETDEWEB)

    Eskildsen, J.; Grandjean, P.

    1984-05-01

    In a cross-sectional study of adult swans and their successfully fledged young in Ringkobing Fjord, West Jutland, Denmark, 128 venous blood samples were taken during the moulting period and analyzed for lead. While the juveniles generally showed blood lead levels below 15 micrograms/100 ml (median, 11 micrograms/100 ml), the values were significantly higher in adults (median, 25 micrograms/100 ml). Adult females showed slightly higher levels than did adult males. None of the birds examined showed signs of acute lead toxicity, and increased blood levels in adults may reflect increased lead body burdens from previous ingestion of lead shot as gizzard stones.

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

    Science.gov (United States)

    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, probotic 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 (probotic PCI the median head-level exposure was 0.1 [0.2] μSv, which was 99.3% less than manual PCI performed with traditional lead (probotics 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.

  12. A framework for widespread replication of a highly spatially resolved childhood lead exposure risk model.

    Science.gov (United States)

    Kim, Dohyeong; Galeano, M Alicia Overstreet; Hull, Andrew; Miranda, Marie Lynn

    2008-12-01

    Preventive approaches to childhood lead poisoning are critical for addressing this longstanding environmental health concern. Moreover, increasing evidence of cognitive effects of blood lead levels system-based childhood lead exposure risk models, especially if executed at highly resolved spatial scales, can help identify children most at risk of lead exposure, as well as prioritize and direct housing and health-protective intervention programs. However, developing highly resolved spatial data requires labor-and time-intensive geocoding and analytical processes. In this study we evaluated the benefit of increased effort spent geocoding in terms of improved performance of lead exposure risk models. We constructed three childhood lead exposure risk models based on established methods but using different levels of geocoded data from blood lead surveillance, county tax assessors, and the 2000 U.S. Census for 18 counties in North Carolina. We used the results to predict lead exposure risk levels mapped at the individual tax parcel unit. The models performed well enough to identify high-risk areas for targeted intervention, even with a relatively low level of effort on geocoding. This study demonstrates the feasibility of widespread replication of highly spatially resolved childhood lead exposure risk models. The models guide resource-constrained local health and housing departments and community-based organizations on how best to expend their efforts in preventing and mitigating lead exposure risk in their communities.

  13. 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?

    Science.gov (United States)

    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. Copyright © 2015 Elsevier Ltd. All rights reserved.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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. Copyright © 2013 Elsevier B.V. All rights reserved.

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

    Science.gov (United States)

    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

  17. Blood Lead Levels And Potental Environmental Exposures Among ...

    African Journals Online (AJOL)

    p = 0.439). Low risk parental occupation (p = 0.001) and. Kales sourced from the market/kiosks (p = 0.001) were significantly associated with BLL ≥ 10ug/dl. Soil lead levels (Soil Pb) ranged from 3,000 to 90,000ug/kg, which was very high ...

  18. Environmental lead exposure among preschool children in Shanghai, China: blood lead levels and risk factors.

    Directory of Open Access Journals (Sweden)

    Jia Cao

    Full Text Available OBJECTIVE: To determine blood lead levels and to identify related risk factors among children in Shanghai; to explore the lead change trend of children after industrial transformation and to provide data for policy development to control environmental lead pollution in Shanghai. METHODS: A stratified-clustered-random sampling method was used. A tungsten atomizer absorption spectrophotometer was employed to determine blood lead levels. RESULTS: The arithmetic mean, geometric mean and median of blood lead levels of 0- to 6-year-old children from Shanghai were 22.49 µg/L, 19.65 µg/L and 19.5 µg/L, including 0.26% (6/2291 with concentrations ≥100 µg/L and 2.7% (61/2291 with concentrations ≥50 µg/L. Boys' levels (23.57 µg/L were greater than those of girls (21.2 µg/L. The blood lead levels increased with age. This survey showed that the Chongming district was the highest and Yangpu district was the lowest, this result is completely opposite with the earlier survey in Shanghai. Risk factors for lead contamination included housing environment, parents' education levels, social status, hobbies, and children's nutritional status. CONCLUSIONS: The blood lead levels of children in Shanghai were lower than the earlier data of Shanghai and those of published studies in China, but higher than the blood lead levels of developed countries. The blood lead levels of urban districts are higher than the central districts with the industrial transformation. Society and the government should take an active interest in childhood lead poisoning of urban areas.

  19. End-stage renal disease after occupational lead exposure: 20 years of follow-up.

    Science.gov (United States)

    Evans, Marie; Discacciati, Andrea; Quershi, Abdul Rashid; Åkesson, Agneta; Elinder, Carl-Gustaf

    2017-06-01

    Whether low-level exposure to lead may give rise to chronic kidney disease or end-stage renal disease (ESRD) is debated. In this study, we aimed to specifically investigate if low-level occupational exposure to lead was associated with increased incidence of ESRD. The incidence of starting renal replacement therapy as a result of ESRD was examined in a cohort of10 303 lead-workers who had controlled blood lead concentrations due to a compulsory occupational health surveillance programme in Sweden during the time period 1977-1990. The ESRD incidence (obtained through register-linkage) among the lead-exposed workers was compared with the age, sex and calendar period-adjusted expected incidence based on data from the Swedish renal registry. Dose-response association was evaluated in external (general population) and internal (within the occupational cohort) comparisons by highest achieved blood lead level. There were 30 (0.29%) individuals in the cohort who developed ESRD during the median follow-up period of 26.3 years. The standardised incidence ratio (SIR) for ESRD incidence was 0.79 (95% CI 0.54 to 1.13). Among those who achieved the highest blood lead (>41.4 µg/dL), the SIR was 1.01 (0.44 to 1.99). There was no evidence of a dose-response relationship between the maximum achieved blood lead or the cumulative blood lead exposure and ESRD in external or internal comparisons. This study of workers with documented occupational lead exposures followed for 20 years shows no statistically significant association between lead exposure (following the current occupational recommendations for Sweden) and ESRD. 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/.

  20. Critical reflections on the currently leading definition of sustainable employability.

    Science.gov (United States)

    Fleuren, Bram Bi; de Grip, Andries; Jansen, Nicole Wh; Kant, Imjert; Zijlstra, Fred Rh

    2016-06-01

    Sustainable employability (SE) is an important topic as it deals with employees' abilities to function adequately at work and in the labor market throughout their working lives. However, until now there has been only one attempt to define SE in the international literature (1). This first definition is a valuable contribution to the field as it rightfully describes SE as a multidimensional concept, recognizes the importance of both employee and work characteristics, and acknowledges the inherently longitudinal nature of SE. Despite these merits, we argue that this definition of SE has some serious omissions that are important in capturing SE comprehensively. Specifically, we argue that the definition could be improved in various ways, namely, it should: (i) clarify which aspects of employment constitute someone's SE; (ii) not counterintuitively treat SE as a characteristic of both the job and the employee simultaneously; (iii) not be based on the insufficiently tested assumption that achieving value in work inherently leads to SE; (iv) be formulated in a way that SE can also apply to unemployed individuals; and (v) adequately specify how the inherently longitudinal dimension of SE should be addressed. We would like to contribute to the discussion by providing guidelines for a new adjusted definition of SE that could facilitate further research on this important concept and its determinants. Introduction SE is a topic of vital importance to individual employees, organizations and society alike. It generally refers to employees' capacities to function in work throughout their working life. As participation in work is important for individuals, organizations, and society as a whole, individuals' ability to function in work is essential. For individuals, work provides meaning, financial security as well as social contacts. Organizations need productive employees to survive. Also from a societal perspective, it is important that as many people as possible participate in

  1. Persistent Organic Pollutant Exposure Leads to Insulin Resistance Syndrome

    DEFF Research Database (Denmark)

    Ruzzin, Jérôme; Petersen, Rasmus; Meugnier, Emmanuelle

    2010-01-01

    BACKGROUND: The incidence of the insulin resistance syndrome has increased at an alarming rate worldwide creating a serious challenge to public health care in the 21st century. Recently, epidemiological studies have associated the prevalence of type 2 diabetes with elevated body burdens...... of persistent organic pollutants (POPs). However, experimental evidence demonstrating a causal link between POPs and the development of insulin resistance is lacking. OBJECTIVE: We investigated whether exposure to POPs contributes to insulin resistance and metabolic disorders. METHODS: Wistar rats were exposed...... salmon oil. We measured body weight, whole-body insulin sensitivity, POP accumulation, lipid and glucose homeostasis, gene expression and performed microarray analysis. RESULTS: Adult male rats exposed to crude, but not refined, salmon oil developed insulin resistance, abdominal obesity...

  2. Motor activity changes induced by sub-encephalopathic lead exposure during different developmental phases in rats

    International Nuclear Information System (INIS)

    Van Rooyen, J.M.; Offermeier, J.; Brand, L.; Botha, F.; Rossouw, J.; Lategan, A.J.; Botes, M.S.

    1988-01-01

    Two groups of rats were exposed to lead (0,2% lead acetate in drinking water) for periods of 21 days during different developmental phases. Lead exposure was initiated on day 1 and day 22 after birth, for rats in groups 1 and 2, respectively. Measurements of locomotor activity (LA) and [ 3 H]spiperone binding assays were performed on day 50 after birth. Lead exposure resulted in the potentiation of the LA effects of 5 mg/kg apomorphine without altering the LA effects of 50 mg/kg piribedil in group 1. Lead exposure resulted in an attenuation of the LA effects of apomorphine and piribedil in group 2. Lead exposure did not alter the K D and B max values of [ 3 H]spiperone in membranes prepared from the rat striatum or nucleus accumbens

  3. Motor activity changes induced by sub-encephalopathic lead exposure during different developmental phases in rats

    Energy Technology Data Exchange (ETDEWEB)

    Van Rooyen, J M; Offermeier, J; Brand, L; Botha, F; Rossouw, J; Lategan, A J; Botes, M S

    1988-05-01

    Two groups of rats were exposed to lead (0,2% lead acetate in drinking water) for periods of 21 days during different developmental phases. Lead exposure was initiated on day 1 and day 22 after birth, for rats in groups 1 and 2, respectively. Measurements of locomotor activity (LA) and (/sup 3/H)spiperone binding assays were performed on day 50 after birth. Lead exposure resulted in the potentiation of the LA effects of 5 mg/kg apomorphine without altering the LA effects of 50 mg/kg piribedil in group 1. Lead exposure resulted in an attenuation of the LA effects of apomorphine and piribedil in group 2. Lead exposure did not alter the K/sub D/ and B/sub max/ values of (/sup 3/H)spiperone in membranes prepared from the rat striatum or nucleus accumbens.

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

    Science.gov (United States)

    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

  5. Cadmium, mercury, and lead in kidney cortex of living kidney donors: Impact of different exposure sources,

    Energy Technology Data Exchange (ETDEWEB)

    Barregard, Lars, E-mail: lars.barregard@amm.gu.se [Department of Occupational and Environmental Medicine, Sahlgrenska University Hospital and University of Gothenburg, P.O. Box 414, SE 405 30 Gothenburg (Sweden); Fabricius-Lagging, Elisabeth [Department of Nephrology, Sahlgrenska University Hospital and Boras Hospital (Sweden); Lundh, Thomas [Department of Occupational and Environmental Medicine, Lund University Hospital and Lund University (Sweden); Moelne, Johan [Department of Clinical Pathology, Sahlgrenska University Hospital and University of Gothenburg (Sweden); Wallin, Maria [Department of Occupational and Environmental Medicine, Sahlgrenska University Hospital and University of Gothenburg, P.O. Box 414, SE 405 30 Gothenburg (Sweden); Olausson, Michael [Department of Transplantation and Liver Surgery, Sahlgrenska University Hospital and University of Gothenburg (Sweden); Modigh, Cecilia; Sallsten, Gerd [Department of Occupational and Environmental Medicine, Sahlgrenska University Hospital and University of Gothenburg, P.O. Box 414, SE 405 30 Gothenburg (Sweden)

    2010-01-15

    Background: Most current knowledge on kidney concentrations of nephrotoxic metals like cadmium (Cd), mercury (Hg), or lead (Pb) comes from autopsy studies. Assessment of metal concentrations in kidney biopsies from living subjects can be combined with information about exposure sources like smoking, diet, and occupation supplied by the biopsied subjects themselves. Objectives: To determine kidney concentrations of Cd, Hg, and Pb in living kidney donors, and assess associations with common exposure sources and background factors. Methods: Metal concentrations were determined in 109 living kidney donors aged 24-70 years (median 51), using inductively coupled plasma-mass spectrometry (Cd and Pb) and cold vapor atomic fluorescence spectrometry (Hg). Smoking habits, occupation, dental amalgam, fish consumption, and iron stores were evaluated. Results: The median kidney concentrations were 12.9 {mu}g/g (wet weight) for cadmium, 0.21 {mu}g/g for mercury, and 0.08 {mu}g/g for lead. Kidney Cd increased by 3.9 {mu}g/g for a 10 year increase in age, and by 3.7 {mu}g/g for an extra 10 pack-years of smoking. Levels in non-smokers were similar to those found in the 1970s. Low iron stores (low serum ferritin) in women increased kidney Cd by 4.5 {mu}g/g. Kidney Hg increased by 6% for every additional amalgam surface, but was not associated with fish consumption. Lead was unaffected by the background factors surveyed. Conclusions: In Sweden, kidney Cd levels have decreased due to less smoking, while the impact of diet seems unchanged. Dental amalgam is the main determinant of kidney Hg. Kidney Pb levels are very low due to decreased exposure.

  6. Cadmium, mercury, and lead in kidney cortex of living kidney donors: Impact of different exposure sources,

    International Nuclear Information System (INIS)

    Barregard, Lars; Fabricius-Lagging, Elisabeth; Lundh, Thomas; Moelne, Johan; Wallin, Maria; Olausson, Michael; Modigh, Cecilia; Sallsten, Gerd

    2010-01-01

    Background: Most current knowledge on kidney concentrations of nephrotoxic metals like cadmium (Cd), mercury (Hg), or lead (Pb) comes from autopsy studies. Assessment of metal concentrations in kidney biopsies from living subjects can be combined with information about exposure sources like smoking, diet, and occupation supplied by the biopsied subjects themselves. Objectives: To determine kidney concentrations of Cd, Hg, and Pb in living kidney donors, and assess associations with common exposure sources and background factors. Methods: Metal concentrations were determined in 109 living kidney donors aged 24-70 years (median 51), using inductively coupled plasma-mass spectrometry (Cd and Pb) and cold vapor atomic fluorescence spectrometry (Hg). Smoking habits, occupation, dental amalgam, fish consumption, and iron stores were evaluated. Results: The median kidney concentrations were 12.9 μg/g (wet weight) for cadmium, 0.21 μg/g for mercury, and 0.08 μg/g for lead. Kidney Cd increased by 3.9 μg/g for a 10 year increase in age, and by 3.7 μg/g for an extra 10 pack-years of smoking. Levels in non-smokers were similar to those found in the 1970s. Low iron stores (low serum ferritin) in women increased kidney Cd by 4.5 μg/g. Kidney Hg increased by 6% for every additional amalgam surface, but was not associated with fish consumption. Lead was unaffected by the background factors surveyed. Conclusions: In Sweden, kidney Cd levels have decreased due to less smoking, while the impact of diet seems unchanged. Dental amalgam is the main determinant of kidney Hg. Kidney Pb levels are very low due to decreased exposure.

  7. Lead exposure is associated with risk of impaired coagulation in preschool children from an e-waste recycling area.

    Science.gov (United States)

    Zeng, Zhijun; Huo, Xia; Zhang, Yu; Xiao, Zhehong; Zhang, Yuling; Xu, Xijin

    2018-05-12

    Environmental lead exposure leads to various deleterious effects on multiple organs and systems, including the hematopoietic system. To explore the effects of lead exposure on platelet indices in preschool children from an informal, lead-contaminated electronic waste (e-waste) recycling area, we collected venous blood samples from 466 preschool children (331 from an e-waste area (Guiyu) and 135 from a non-e-waste area (Haojiang)). Child blood lead levels (BLLs) were determined by graphite furnace atomic absorption spectrophotometry, while platelet indices were quantified using a Sysmex XT-1800i hematology analyzer. Higher blood lead levels are observed in e-waste lead-exposed preschool children. Significant relationships between high blood lead levels (exceeding current health limits) and elevated platelet count (PLT), plateletcrit (PCT), mean platelet volume (MPV), and platelet large cell ratio (P-LCR) were also uncovered. Furthermore, the median PLT and PCT levels of children from the exposed group both exceeded the respective recommended maximum reference range value, whereas the reference group did not. Location of child residence in Guiyu and BLLs were both risk factors related to platelet indices. These results suggest that high blood lead exposure from e-waste recycling may increase the risk of an amplified coagulation process through the activation of platelets in preschool children.

  8. Report on radiation exposure of lead-scintillator stack

    International Nuclear Information System (INIS)

    Underwood, D.G.

    1990-01-01

    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

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

    Science.gov (United States)

    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).

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

    Science.gov (United States)

    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.

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

    International Nuclear Information System (INIS)

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

    2008-01-01

    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 μg/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 μg/g to an average of 336 μg/g over 4 years. The percent distribution of lead in the fine grain soil (<100 μm) 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 μm) 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

  12. Impact of developmental lead exposure on splenic factors

    International Nuclear Information System (INIS)

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

    2010-01-01

    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.

  13. Blood lead exposure concentrations in mottled ducks (Anas fulvigula) on the upper Texas coast

    Science.gov (United States)

    McDowell, Stephen K.; Conway, Warren C.; Haukos, David A.; Moon, Jena A.; Comer, Christopher E.; Hung, I-Kuai

    2015-01-01

    The mottled duck (Anas fulvigula) is a non-migratory waterfowl species dependent upon coastal marsh systems, including those on the Texas Chenier Plain National Wildlife Refuge (NWR) Complex, and considered a regional indicator species of marsh habitat quality. Research from the early 1970s, 1990s, and early-2000s indicated that mottled ducks continued to exhibit elevated wing-bone lead (Pb) concentrations, decades after implementation of non-toxic shot regulations. However, wing-bone concentrations reflect lifetime accumulation of Pb, whereas blood Pb concentrations reflect more recent exposure. To identify current potentially relevant temporal windows of Pb exposure, we collected 260 blood samples from mottled ducks during summer (n=124) and winter (n=136) from 2010–2012 on the Texas Chenier Plain NWR Complex. We quantified baseline blood Pb concentrations for all ages of mottled ducks, and hypothesized that blood lead concentrations would remain elevated above background levels (200 µg L–1) despite the 1983 and 1991 lead shot bans. Blood Pb concentrations ranged from below detection limits to >12,000 µg L–1, where >200 µg L–1 was associated with exposure levels above background concentrations. Male mottled ducks had the greatest blood Pb concentrations (30 times greater than females) with concentrations greater during winter than summer. Likewise, the proportion of exposed (>200 µg L–1) females increased from 14%–47% from summer to winter, respectively. Regardless of sex, adult mottled duck blood Pb concentrations were five times greater than juveniles, particularly during winter. We identified five plausible models that influenced blood Pb levels where year, site, and interactions among age*sex*season and between age*season were included in the top-ranked models. Frequency of exposure was greatest during winter, increasing from 12% in summer to 55% in winter, indicating that a temporal exposure window to environmental Pb exists between nesting

  14. An examination of knowledge, attitudes and practices related to lead exposure in South Western Nigeria

    Directory of Open Access Journals (Sweden)

    Sridhar Mynepalli KC

    2006-03-01

    Full Text Available Abstract Background Lead is a highly toxic and pervasive metal. Chronic exposure to low levels is responsible for significant health effects, particularly in children. Prevention remains the best option for reducing childhood lead exposure, however the knowledge, attitudes and practices to lead exposure in many developing countries is not known. Methods: We conducted four focus group discussions (FGD to evaluate knowledge attitudes and practices to lead exposure in Nigeria. An FGD guide was developed from the literature and preliminary discussion with members of the public. Participants in the FGD were randomly selected from adults living in Ibadan, South Western Nigeria in 2004. Results We found that there was limited awareness of the sources of lead exposure in the domestic environment and participants had little knowledge of the health effects of chronic low-dose lead exposure. Conclusion We conclude that the findings of this study should be used, in conjunction with others, to develop appropriate health education intervention for lead exposure in the domestic environment.

  15. Are Lead Exposures a Risk in European Fresh Waters? A Regulatory Assessment Accounting for Bioavailability.

    Science.gov (United States)

    Peters, Adam; Wilson, Iain; Merrington, Graham; Chowdhury, M Jasim

    2018-01-01

    An indicative compliance assessment of the Europe-wide bioavailable lead Environmental Quality Standard of 1.2 µg L -1 (EQS) was undertaken against regulatory freshwater monitoring data from six European member states and FOREGS database. Bio-met, a user-friendly tool based upon Biotic Ligand Models (BLMs) was used to account for bioavailability, along with the current European Water Framework Directive lead dissolved organic carbon correction approach. The outputs from both approaches were compared to the BLM. Of the 9054 freshwater samples assessed only 0.6% exceeded the EQS of 1.2 µg L -1 after accounting for bioavailability. The data showed that ambient background concentrations of lead across Europe are unlikely to influence general compliance with the EQS, although there may be isolated local issues. The waters showing the greatest sensitivity to potential lead exposures are characterized by relatively low DOC (< 0.5 mg L -1 ), regardless of the pH and calcium concentrations.

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

    Science.gov (United States)

    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 (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 (lead remediation on a yard-by-yard scale requires constant maintenance and that remediation may need to occur on a neighborhood-wide scale.

  17. Occurrence of lead-related symptoms below the current occupational safety and health act allowable blood lead levels.

    Science.gov (United States)

    Rosenman, Kenneth D; Sims, Amy; Luo, Zhehui; Gardiner, Joseph

    2003-05-01

    To determine the occurrence of symptoms of lead toxicity at levels below the current allowable Occupational Safety and Health Act blood lead level of 50 micrograms/dL, standardized telephone interviews were conducted of individuals reported to a statewide laboratory-based surveillance system. Four hundred and ninety-seven, or 75%, of the eligible participants were interviewed. Gastrointestinal, musculoskeletal, and nervous system symptoms increased with increasing blood lead levels. Nervous, gastrointestinal, and musculoskeletal symptoms all began to be increased in individuals with blood leads between 30-39 micrograms/dL and possibly at levels as low as 25-30 micrograms/dL for nervous system symptoms. The results of this study of increased symptoms are consistent with and provide added weight to previous results showing subclinical changes in the neurologic and renal systems and sperm counts at blood lead levels currently allowed by the Occupational Safety and Health Act.

  18. Unintentional and Sequential Lead Exposure from a Ceramic Mug and Maca (Lepidium meyenii).

    Science.gov (United States)

    Johnson-Arbor, Kelly; Vo, Kathy; Wong, Flavia; Gajek, Ryszard

    2018-06-01

    Although the incidence of lead poisoning has decreased in the USA over the last 30 years, human exposures to lead-containing products are still reported. We present a case of unintentional lead exposure from a store-bought ceramic mug and a nutritional supplement. A 32-year-old female was found to have a whole blood lead concentration of 44 μg/dL. Evaluation of her home, occupation, and hobbies initially did not identify a source of lead exposure. Further investigation revealed that the likely etiology of the exposure was lead leaching from a ceramic mug used by the patient to drink hot lemon water while she was pregnant. She stopped drinking from the mug and her blood lead levels decreased, but increased a year later after she began to ingest a maca root powder supplement. Upon discontinuation of maca root powder ingestion, her blood lead levels decreased further. Over time, the acidity and heat of the hot lemon water used in the ceramic mug enhanced the breakdown of its leaded glaze. Maca powder, which is available as a nutritional supplement and is used to treat fatigue and enhance fertility, may contain lead and other minerals. Consumers, particularly women of childbearing age, and their physicians should be aware that imported products available from commercial retailers and internet vendors may contain significant amounts of lead.

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

    Energy Technology Data Exchange (ETDEWEB)

    Madder, Ryan D., E-mail: ryan.madder@spectrumhealth.org; VanOosterhout, Stacie; Mulder, Abbey; Elmore, Matthew; Campbell, Jessica; Borgman, Andrew; Parker, Jessica; Wohns, David

    2017-04-15

    Background: 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). Methods: 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. Results: Among 336 cases (86.6% manual, 13.4% robotic) performed over 30 weeks, 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). Conclusions: 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. - Highlights: • Use of suspended lead during manual PCI reduced cranial radiation among operators by 97%. • Robotic PCI reduced cranial radiation among operators by 99%. • Suspended lead and robotics together achieved the lowest levels of radiation exposure.

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

    International Nuclear Information System (INIS)

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

    2017-01-01

    Background: 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). Methods: 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. Results: Among 336 cases (86.6% manual, 13.4% robotic) performed over 30 weeks, 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). Conclusions: 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. - Highlights: • Use of suspended lead during manual PCI reduced cranial radiation among operators by 97%. • Robotic PCI reduced cranial radiation among operators by 99%. • Suspended lead and robotics together achieved the lowest levels of radiation exposure.

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

    Energy Technology Data Exchange (ETDEWEB)

    Slaby, Sylvain [Univ. Lille Nord de France, EA 4515 – LGCgE – Laboratoire Génie Civil et géo-Environnement, Université de Lille 1, Cité scientifique, SN3, F-59655 Villeneuve d’Ascq (France); Univ. Lille, CNRS, INRA, UMR 8576 – UGSF – Unité de Glycobiologie Structurale et Fonctionnelle, F-59000 Lille (France); Lemière, Sébastien [Univ. Lille Nord de France, EA 4515 – LGCgE – Laboratoire Génie Civil et géo-Environnement, Université de Lille 1, Cité scientifique, SN3, F-59655 Villeneuve d’Ascq (France); Hanotel, Julie; Lescuyer, Arlette [Univ. Lille, CNRS, INRA, UMR 8576 – UGSF – Unité de Glycobiologie Structurale et Fonctionnelle, F-59000 Lille (France); Demuynck, Sylvain [Univ. Lille Nord de France, EA 4515 – LGCgE – Laboratoire Génie Civil et géo-Environnement, Université de Lille 1, Cité scientifique, SN3, F-59655 Villeneuve d’Ascq (France); Bodart, Jean-François [Univ. Lille, CNRS, INRA, UMR 8576 – UGSF – Unité de Glycobiologie Structurale et Fonctionnelle, F-59000 Lille (France); and others

    2016-08-15

    Highlights: • First embryonic steps were studied. • Fertilization success was impacted by cadmium exposures. • Oocytes were most affected instead of spermatozoa by cadmium exposures. • First embryonic cleavages were slown down or stopped by cadmium exposures. • Lead exposures did not affected fertilization and segmentation. - Abstract: 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.

  2. A safe strategy to decrease fetal lead exposure in a woman with chronic intoxication.

    Science.gov (United States)

    Leiba, Adi; Hu, Howard; Zheng, Amin; Kales, Stefanos N

    2010-08-01

    During pregnancy skeletal lead is mobilized by maternal bone turnover and can threaten fetal development. The exact strategy suggested to women of childbearing age, who were chronically exposed to lead, and, thus, have high bone lead burden, is not well established. We describe 4 years of follow-up of a 29-year-old woman with chronic lead intoxication. We (a) advised her to delay conception until 'toxicological clearance', (b) treated her with multiple courses of lead chelator, DMSA, and (c) prescribed oral calcium. Patient had low blood lead and protoporphyrin level during pregnancy until delivery. Delaying conception, lead chelation, and calcium supplementation can decrease fetal exposure.

  3. Lead in school drinking water: Canada can and should address this important ongoing exposure source.

    Science.gov (United States)

    Barn, Prabjit; Kosatsky, Tom

    2011-01-01

    Reducing all preventable lead exposures in children should be a public health priority given that blood lead levels in children that were once considered "safe" have since been associated with important neuro-developmental deficits. Limited Canadian data indicate that school drinking water can be an important component of children's overall exposure to lead. Outside of Ontario, however, Canadian schools are not required to test for lead in water; in most of Canada, school testing is case by case, typically initiated by parental concerns. Provinces and territories are encouraged to follow Ontario's example by instituting a routine school water lead testing program in order to identify facilities where action can result in a decrease in students' exposure to lead. Testing and remediation frameworks developed by the US Environmental Protection Agency, Health Canada, and the province of Ontario provide direction to school boards and local and provincial/territorial health authorities.

  4. Association of Lead Exposure, Serum Uric Acid and Parameters of Renal Function in Nigerian Lead-Exposed Workers

    Directory of Open Access Journals (Sweden)

    DD Alasia

    2010-09-01

    Full Text Available Background: The presence of hyperuricemia and renal function impairment, especially in the absence of urate stone formation is strongly suggestive of lead nephropathy. The evaluation of this association is essential in areas where lead exposure is still prevalent and uncontrolled. Objective: To determine the relationship between serum uric acid and renal function indices in lead-exposed workers. Methods: A cross-sectional study of 190 adults with occupational lead exposure and 80 adults (comparison group, matched for age and sex was performed in Port Harcourt, South-south Nigeria. Blood lead was used as the biomarker of lead exposure while serum urea, serum creatinine, urine albumin (using urine albumin:creatinine ratio, estimated glomerular filtration rate (GFR and serum uric acid were the renal function indices measured. Results: Occupationally lead-exposed subjects had a significantly (p = 0.008 higher mean±SD blood lead levels (50.37±24.58 μg/dL than the comparison group (41.40±26.85. The mean±SD serum urea (8.6±2.3 mg/dL, creatinine (1.0±0.2 mg/dL and serum uric acid (4.6±1.2 mg/dL were significantly (p < 0.01 higher in the study subjects than the comparison group (7.6±2.4, 0.9±0.2, and 3.9±1.1 mg/dL, respectively. The mean±SD creatinine clearance was significantly (p = 0.002 lower in the study subjects than the comparison group (98.9±21.3 vs. 108.2±25.2 mL/min/1.72 m2. Serum uric acid level correlated positively with serum creatinine (r = 0.134 and negatively with GFR (r = ‑0.151. Conclusion: People with occupational lead exposure are at risk of developing hyperuricemia and renal impairment.

  5. The change of β-adrenergic system after cessation of lead exposure

    International Nuclear Information System (INIS)

    Chang, H.-R.; Tsao, D.-A.; Yu, H.-S.; Ho, C.-K.

    2005-01-01

    For understanding a reversible or irreversible harm of β-adrenergic system in lead induced cardiovascular disease (hypertension), We set up animal model to estimate the change of blood pressure and sympathetic nervous system after lead exposure withdrawn in the study. We address three topics in this study: (a) the relationship between withdrawal time of lead exposure and β-adrenergic receptor, plasma catecholamine level, blood pressure, and lead level in heart, aorta, and kidney in lead-induced hypertensive rats after lead exposure stopped; (b) the relationship between blood pressure and β-adrenergic receptor in heart, aorta, and kidney; (c) the estimation of relationship between lead withdrawn and the variation of β-adrenergic system. Wistar rats were chronically fed with 2% lead acetate (experimental group) and water (control group) for 2 months. The rats were divided into 8 groups by withdrawal time of lead exposure stopped. Plasma catecholamine level was measured by high-performance liquid chromatography. Radioligand binding assay was measured by a method that fulfilled strict criteria of β-adrenergic receptor using the ligand [ 125 I]iodocyanopindolol. The levels of lead were determined by electrothermal atomic absorption spectrometry. The results showed that a close relation between reduced lead level and the plasma catecholamine level decreased, aorta β-adrenergic receptor increased, kidney β-adrenergic receptor diminished, heart β-adrenergic receptor increased, and blood pressure dropped after lead exposure withdrawn. The study on the regulation of β-adrenergic system in lead-induced hypertension after lead withdrawn might also provide insight about the nature of this disease state

  6. Drift in ocean currents impacts intergenerational microbial exposure to temperature.

    Science.gov (United States)

    Doblin, Martina A; van Sebille, Erik

    2016-05-17

    Microbes are the foundation of marine ecosystems [Falkowski PG, Fenchel T, Delong EF (2008) Science 320(5879):1034-1039]. Until now, the analytical framework for understanding the implications of ocean warming on microbes has not considered thermal exposure during transport in dynamic seascapes, implying that our current view of change for these critical organisms may be inaccurate. Here we show that upper-ocean microbes experience along-trajectory temperature variability up to 10 °C greater than seasonal fluctuations estimated in a static frame, and that this variability depends strongly on location. These findings demonstrate that drift in ocean currents can increase the thermal exposure of microbes and suggests that microbial populations with broad thermal tolerance will survive transport to distant regions of the ocean and invade new habitats. Our findings also suggest that advection has the capacity to influence microbial community assemblies, such that regions with strong currents and large thermal fluctuations select for communities with greatest plasticity and evolvability, and communities with narrow thermal performance are found where ocean currents are weak or along-trajectory temperature variation is low. Given that fluctuating environments select for individual plasticity in microbial lineages, and that physiological plasticity of ancestors can predict the magnitude of evolutionary responses of subsequent generations to environmental change [Schaum CE, Collins S (2014) Proc Biol Soc 281(1793):20141486], our findings suggest that microbial populations in the sub-Antarctic (∼40°S), North Pacific, and North Atlantic will have the most capacity to adapt to contemporary ocean warming.

  7. Antioxidant responses in gills and digestive gland of oyster Crassostrea madrasensis (Preston) under lead exposure

    Digital Repository Service at National Institute of Oceanography (India)

    Shenai-Tirodkar, P.S.; Gauns, M.; Mujawar, M.W.A.; Ansari, Z.A.

    madrasensis against lead (Pb) exposure under laboratory conditions. Antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT), and glutathione-s-transferase (GST) and oxidative damage parameter lipid peroxidation (LPO) were measured in the gills...

  8. Acute high-dose lead exposure from beverage contaminated by traditional Mexican pottery.

    Science.gov (United States)

    Matte, T D; Proops, D; Palazuelos, E; Graef, J; Hernandez Avila, M

    1994-10-15

    Screening and follow-up blood lead measurements in a 7-year-old child of a US Embassy official in Mexico City revealed an increase in blood lead concentration from 1.10 to 4.60 mumol/L in less than 4 weeks. The cause was traced to fruit punch contaminated with lead leached from traditional ceramic pottery urns. Consumption of the contaminated punch at a picnic was associated with a 20% increase in blood lead concentrations among embassy staff and dependants who were tested 6 weeks after the exposure. This episode highlights the continued health risk, even from brief exposure, posed by traditional pottery in Mexico.

  9. Early Childhood Lead Exposure and Academic Achievement: Evidence From Detroit Public Schools, 2008–2010

    Science.gov (United States)

    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

  10. Particle size distributions of lead measured in battery manufacturing and secondary smelter facilities and implications in setting workplace lead exposure limits.

    Science.gov (United States)

    Petito Boyce, Catherine; Sax, Sonja N; Cohen, Joel M

    2017-08-01

    Inhalation plays an important role in exposures to lead in airborne particulate matter in occupational settings, and particle size determines where and how much of airborne lead is deposited in the respiratory tract and how much is subsequently absorbed into the body. Although some occupational airborne lead particle size data have been published, limited information is available reflecting current workplace conditions in the U.S. To address this data gap, the Battery Council International (BCI) conducted workplace monitoring studies at nine lead acid battery manufacturing facilities (BMFs) and five secondary smelter facilities (SSFs) across the U.S. This article presents the results of the BCI studies focusing on the particle size distributions calculated from Personal Marple Impactor sampling data and particle deposition estimates in each of the three major respiratory tract regions derived using the Multiple-Path Particle Dosimetry model. The BCI data showed the presence of predominantly larger-sized particles in the work environments evaluated, with average mass median aerodynamic diameters (MMADs) ranging from 21-32 µm for the three BMF job categories and from 15-25 µm for the five SSF job categories tested. The BCI data also indicated that the percentage of lead mass measured at the sampled facilities in the submicron range (i.e., lead) was generally small. The estimated average percentages of lead mass in the submicron range for the tested job categories ranged from 0.8-3.3% at the BMFs and from 0.44-6.1% at the SSFs. Variability was observed in the particle size distributions across job categories and facilities, and sensitivity analyses were conducted to explore this variability. The BCI results were compared with results reported in the scientific literature. Screening-level analyses were also conducted to explore the overall degree of lead absorption potentially associated with the observed particle size distributions and to identify key issues

  11. When mere exposure leads to less liking: the incremental threat effect in intergroup contexts.

    Science.gov (United States)

    Crisp, Richard J; Hutter, Russell R C; Young, Bryony

    2009-02-01

    In two experiments we tested the hypothesis that repeated exposure to out-group-relevant attitude objects would lead to less liking following a threat to identity. In Experiment 1 exposure to abstract artwork ostensibly created by a member of an out-group university led to more liking under baseline conditions, but not following a manipulation of threat. In Experiment 2 we observed a negative relationship between exposure and liking following threat: liking reversed the typical mere exposure effect. Reported emotion mediated the interactive effect of threat and exposure on liking. These findings illustrate how social identity threat can be experienced incrementally as a function of exposure. We discuss the findings in the context of an integration of research on exposure, identity, attitudes, and contact.

  12. Development of a multiple HTS current lead assembly for corrector magnets application

    International Nuclear Information System (INIS)

    Wu, J.L.; Dederer, J.T.; Singh, S.K.

    1994-01-01

    Vapor-cooled current leads used for transmitting power to superconducting power equipment such as the corrector magnets in the SSC spools can introduce a significant heat leak into the cryostat which results in cryogen boil-off. Replenishing the boil-off or refrigerating and liquefying the vapors associated with the cooling of these leads may constitute a significant portion of the operating cost and/or the capital investment of the power equipment. Theoretical studies and experiments have demonstrated that the heat leak introduced by a current lead can be significantly reduced by using ceramic high temperature superconductor (HTSC) as part of the conductor in the current leads. A HTSC reduces heat leak in a current lead by being superconducting in the temperature range below its critical temperature and by having a low temperature thermal conductivity which is generally orders of magnitude lower than the copper alloys commonly used as the current lead conductors. This combination reduces Joule heating and heat conduction, resulting in lower heat leak to the cryostat. To demonstrate the advantages and large scale application of this technology, Westinghouse Science ampersand Technology Center has continued its efforts in High Temperature Superconducting (HTS) current lead development. The efforts include qualification testing and selection of commercial sources of HTSC for current leads and the successful development of a 12 x 100 A multiple HTS current lead assembly prototype for SSC Corrector Element Power Lead application. The efforts on the design, fabrication and testing of the multiple HTS lead assembly is reported below

  13. Occupational exposures to leaded and unleaded gasoline engine emissions and lung cancer risk.

    Science.gov (United States)

    Xu, Mengting; Siemiatycki, Jack; Lavoué, Jérôme; Pasquet, Romain; Pintos, Javier; Rousseau, Marie-Claude; Richardson, Lesley; Ho, Vikki

    2018-04-01

    To determine whether occupational exposure to gasoline engine emissions (GEE) increased the risk of lung cancer and more specifically whether leaded or unleaded GEE increased the risk. Two population-based case-control studies were conducted in Montreal, Canada. The first was conducted in the early 1980s and included many types of cancer including lung cancer. The second was conducted in the late 1990s and focused on lung cancer. Population controls were used in both studies. Altogether, there were 1595 cases and 1432 population controls. A comprehensive expert-based exposure assessment procedure was implemented and exposure was assessed for 294 agents, including unleaded GEE, leaded GEE and diesel engine emissions (DEE). Logistic regression analyses were conducted to estimate ORs between various metrics of GEE exposure and lung cancer, adjusting for smoking, DEE and other potential confounders. About half of all controls were occupationally exposed to GEE. Irrespective of the metrics of exposure (any exposure, duration of exposure and cumulative exposure) and the type of lung cancer, and the covariates included in models, none of the point estimates of the ORs between occupational exposure to leaded or unleaded GEE and lung cancer were above 1.0. Pooling two studies, the OR for any exposure to leaded GEE was 0.82 (0.68-1.00). Our results do not support the hypothesis that occupational exposure to GEE increases the risk of lung cancer. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  14. Performance and exposure indices of rats exposed to low concentrations of lead.

    Science.gov (United States)

    Cory-Slechta, D A; Weiss, B; Cox, C

    1985-04-01

    To further characterize the lower end of the function relating lead exposure and biological exposure indices to behavior, male weanling rats were exposed chronically to drinking solutions containing 25 ppm sodium acetate (controls) or 25 ppm lead acetate. Behavioral training began when the animals reached 50 days of age, and performance on a fixed-interval 1-min schedule of food reinforcement was then assessed over 90 experimental sessions (136 days). This exposure produced overall response rate increases over the first 40 sessions that were similar to those observed previously with higher concentrations of lead. Response rates of the two groups tended to merge subsequently. The increased overall response rates in the treated group derived primarily from an increased frequency of shorter interresponse times (IRTs) and increased running rates (calculated without the postreinforcement interval). Blood lead (PbB) and zinc protoporphyrin (ZPP) values were determined following sessions 30, 60, and 90. PbB values of the lead-exposed group averaged 15 to 20 micrograms/dl throughout the study; ZPP did not differ. The mean brain lead value of the treated group was 0.07 micrograms Pb/g. Blood-brain ratios (1.38 to 4.06) were substantially greater than those previously observed at higher exposures. These data extend to even lower exposures, and lower blood lead concentrations, the effective concentration for behavioral effects, and further emphasize the importance of the sensitivity of the endpoint in assessing behavioral toxicity.

  15. Children's Lead Exposure: A Multimedia Modeling Analysis to Guide Public Health Decision-Making.

    Science.gov (United States)

    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.

  16. Ultra-Low Heat-Leak, High-Temperature Superconducting Current Leads for Space Applications

    Science.gov (United States)

    Rey, Christopher M.

    2013-01-01

    NASA Goddard Space Flight Center has a need for current leads used in an adiabatic demagnetization refrigerator (ADR) for space applications. These leads must comply with stringent requirements such as a heat leak of approximately 100 W or less while conducting up to 10 A of electric current, from more than 90 K down to 10 K. Additionally, a length constraint of leak leads currently to NASA's specs.

  17. Relevancy of human exposure via house dust to the contaminants lead and asbestos

    NARCIS (Netherlands)

    Oomen AG; Lijzen JPA; SIR; LER

    2004-01-01

    The present report addresses the issues whether house dust is likely to contribute substantially to the exposure of humans, in particular for the contaminants lead and asbestos. House dust consists for 30-70% of soil material, indicating that contaminated soil can lead to contaminated house dust. It

  18. Cognition in children does not suffer from very low lead exposure.

    NARCIS (Netherlands)

    Minder, B.; Das-Smaal, E.A.; Orlebeke, J.F.

    1998-01-01

    We studied the relationship between exposure to lead and memory' and attention in children. Participants were 313 boys aged 9 to 12 years who attended special education schools in the Netherlands. Children whose possible attentional or memory problerns were obviously due to causes other than lead

  19. Fetal exposure to lead during pregnancy and the risk of preterm and early-term deliveries.

    Science.gov (United States)

    Cheng, Lu; Zhang, Bin; Huo, Wenqian; Cao, Zhongqiang; Liu, Wenyu; Liao, Jiaqiang; Xia, Wei; Xu, Shunqing; Li, Yuanyuan

    2017-08-01

    Studies have reported the association between lead exposure during pregnancy and preterm birth. However, findings are still inconsistent. This prospective birth cohort study evaluated the risks of preterm and early-term births and its association with prenatal lead exposure in Hubei, China. A total of 7299 pregnant women were selected from the Healthy Baby Cohort. Maternal urinary lead levels were measured by the Inductively Coupled Plasma Mass Spectrometry. The associations between tertiles of urinary lead levels and the risks of preterm and early-term deliveries were assessed using multiple logistic regression models. The geometric mean of creatinine-adjusted urinary lead concentrations among all participating mothers, preterm birth, and early-term birth were 3.19, 3.68, and 3.17μg/g creatinine, respectively. A significant increase in the risk of preterm births was associated with the highest urinary lead tertile after adjusting for confounders with odds ratio (OR) of 1.96. The association was more pronounced among 25-36 years old mothers with OR of 2.03. Though significant p trends were observed between lead exposure (medium and high tertiles) and the risk of early-term births, their ORs were not significant. Our findings indicate that the risk of preterm birth might increase with higher fetal lead exposure, particularly among women between the age of 25 and 36 years. Copyright © 2017 Elsevier GmbH. All rights reserved.

  20. Selected important fragrance sensitizers in perfumes--current exposures.

    Science.gov (United States)

    Rastogi, Suresh Chandra; Johansen, Jeanne Duus; Bossi, Rossana

    2007-04-01

    Contact allergy to fragrance ingredients is frequent. Recommendations and regulations of some of the most frequent and potent fragrance allergens have recently been introduced. To investigate current exposures to 4 important fragrance allergens in hydroalcoholic cosmetic products. 25 popular perfume products of Danish as well as international brands were purchased from the Danish retail market. Contents of 4 important fragrance allergens, isoeugenol, hydroxy-iso-hexyl 3-cyclohexene carboxaldehyde (HICC, Lyral), were determined by gas chromatography-mass spectrometry, and atranol and chloro-atranol were determined by liquid chromatography-tandem mass spectrometry. Isoeugenol was found in 56%, HICC in 72%, atranol in 59%, and chloro-atranol in 36% of the 22 eau de toilette/eau de parfum products. The concentrations of isoeugenol were, in all products, below the recommended maximum concentration of 0.02%. HICC reached a maximum of 0.2%, which is 10-fold higher than maximum tolerable concentration considered safe by the EU Scientific Committee. The median concentrations of atranol and chloro-atranol in the investigated products were similar to those found in similar products in 2003. A significant decrease in the frequency of presence of chloro-atranol in the products was observed. There is still a wide-spread exposure to potent fragrance allergens in perfumes.

  1. Chronic lead exposure induces cochlear oxidative stress and potentiates noise-induced hearing loss.

    Science.gov (United States)

    Jamesdaniel, Samson; Rosati, Rita; Westrick, Judy; Ruden, Douglas M

    2018-08-01

    Acquired hearing loss is caused by complex interactions of multiple environmental risk factors, such as elevated levels of lead and noise, which are prevalent in urban communities. This study delineates the mechanism underlying lead-induced auditory dysfunction and its potential interaction with noise exposure. Young-adult C57BL/6 mice were exposed to: 1) control conditions; 2) 2 mM lead acetate in drinking water for 28 days; 3) 90 dB broadband noise 2 h/day for two weeks; and 4) both lead and noise. Blood lead levels were measured by inductively coupled plasma mass spectrometry analysis (ICP-MS) lead-induced cochlear oxidative stress signaling was assessed using targeted gene arrays, and the hearing thresholds were assessed by recording auditory brainstem responses. Chronic lead exposure downregulated cochlear Sod1, Gpx1, and Gstk1, which encode critical antioxidant enzymes, and upregulated ApoE, Hspa1a, Ercc2, Prnp, Ccl5, and Sqstm1, which are indicative of cellular apoptosis. Isolated exposure to lead or noise induced 8-12 dB and 11-25 dB shifts in hearing thresholds, respectively. Combined exposure induced 18-30 dB shifts, which was significantly higher than that observed with isolated exposures. This study suggests that chronic exposure to lead induces cochlear oxidative stress and potentiates noise-induced hearing impairment, possibly through parallel pathways. Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.

  2. Effects of acute and chronic exposure to lead on the behavior of the pond snail Helisoma trivolvis

    Energy Technology Data Exchange (ETDEWEB)

    Bennett, V.T.; Copeland, J. [Georgia Southern Univ., Statesboro, GA (United States)

    1997-09-01

    The behavior of aquatic invertebrates may be useful as an indicator for the presence of toxicants in both freshwater and marine environments. The pond snail Helisoma trivolvis, the red ram`s horn, was exposed to low levels of lead (0.05 ppm). Chronic exposure significantly reduced the number of head movements but had no affect on radula movement or antenna twitches. Acute exposure resulted in curling of the foot that lasted 0.5 to 14.0 minutes. Electrochemical analysis of lead levels within treated snails indicated a higher concentration of lead in the tissue than that in the treated environment. Organ analysis of the digestive gland, 1 salivary gland, reproductive organs and the cerebral ganglion is currently being studied.

  3. Lead exposure affects health indices in free-ranging ducks in Argentina.

    Science.gov (United States)

    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.

  4. Influence of minerals on lead-induced alterations in liver function in rats exposed to long-term lead exposure

    International Nuclear Information System (INIS)

    Herman, D'souza Sunil; Geraldine, Menezes; T, Venkatesh

    2009-01-01

    The objective of this study was to evaluate the role of minerals on lead-induced effect on the liver. Differentiation of minerals and heavy metals pose an inherent problem due to certain common properties shared by them. With this approach to the problem of heavy metal toxicity, in the present study two groups of male Wistar albino rats, one group (well-nourished) fed on mineral rich diet and other group (undernourished) fed on diet without mineral supplements were used. Both the groups of rats were subjected to long-term lead exposure. The diet of well-nourished group was supplemented with calcium (Ca); 1.2%, phosphorous (P); 0.6%, iron (Fe); 90 mg/kg, zinc (Zn); 50 mg/kg, magnesium (Mg); 0.08%, manganese (Mn); 70 mg/kg, selenium (Se); 0.2 mg/kg, copper (Cu); 5 mg/kg, molybdenum (Mo); 0.8 mg/kg, iodine (I); 0.6 mg/kg, cobalt (Co); 3.0 mg/kg. Their blood lead and parameters of liver function were monitored periodically. Results of the study showed a very high statistically significant increase (p < 0.001) in the blood lead (PbB) levels and liver function test parameters in the undernourished subjects compared to the well-nourished subjects. Nutritional management of lead poisoning is of importance since essential elements and toxic heavy metals may interact to minimize the absorption of lead.

  5. Influence of minerals on lead-induced alterations in liver function in rats exposed to long-term lead exposure

    Energy Technology Data Exchange (ETDEWEB)

    Herman, D' souza Sunil, E-mail: hermansdsouza@rediffmail.com [Department of Biotechnology, Manipal Life Sciences Centre, KMC, Manipal University, Manipal (India); Geraldine, Menezes, E-mail: gere1@rediffmail.com [Department of Biochemistry and Biophysics, St. John' s Medical College, Koramangala, Bangalore 560034, Karnataka (India); T, Venkatesh, E-mail: venky_tv@hotmail.com [Department of Biochemistry and Biophysics, St. John' s Medical College, Koramangala, Bangalore 560034, Karnataka (India)

    2009-07-30

    The objective of this study was to evaluate the role of minerals on lead-induced effect on the liver. Differentiation of minerals and heavy metals pose an inherent problem due to certain common properties shared by them. With this approach to the problem of heavy metal toxicity, in the present study two groups of male Wistar albino rats, one group (well-nourished) fed on mineral rich diet and other group (undernourished) fed on diet without mineral supplements were used. Both the groups of rats were subjected to long-term lead exposure. The diet of well-nourished group was supplemented with calcium (Ca); 1.2%, phosphorous (P); 0.6%, iron (Fe); 90 mg/kg, zinc (Zn); 50 mg/kg, magnesium (Mg); 0.08%, manganese (Mn); 70 mg/kg, selenium (Se); 0.2 mg/kg, copper (Cu); 5 mg/kg, molybdenum (Mo); 0.8 mg/kg, iodine (I); 0.6 mg/kg, cobalt (Co); 3.0 mg/kg. Their blood lead and parameters of liver function were monitored periodically. Results of the study showed a very high statistically significant increase (p < 0.001) in the blood lead (PbB) levels and liver function test parameters in the undernourished subjects compared to the well-nourished subjects. Nutritional management of lead poisoning is of importance since essential elements and toxic heavy metals may interact to minimize the absorption of lead.

  6. Biological assessment of continuous exposure to tritium and lead in the rat

    International Nuclear Information System (INIS)

    Cahill, D.F.; Reiter, L.W.; Santolucito, J.A.; Rehnberg, G.I.; Ash, M.E.; Favor, M.J.; Bursian, S.J.; Wriht, J.F.; Laskey, J.W.

    1976-01-01

    A broad investigation of the effects of simultaneous exposure to two potentially synergistic environmental pollutants, tritiated water (HTO) and lead, was conducted. Sprague-Dawley rats were continuously exposed to HTO and/or Pb in drinking water from conception of the F 1 through adulthood of the F 2 generation. A l2-cell exposure matrix was used employing HTO activities calculated to provide approximately 3-300 mrad/d whole-body irradiation and Pb levels of 5 or 50 ppm in drinking water. Observations were made on the reproductive capacity of the F 1 generation and the effects of lifetime parental exposure to HTO and/or lead on the F 2 neonates. The effects of single and combined exposures on the development and function of the central nervous system, some brain catecholamine levels and electroencephalogram patterns were also examined in both generations. The results indicate that, in both generations, continuous HTO exposures as low as 3 mrad/d delayed development of righting reflexes in young rats; 30 mrad/d additionally depressed the spontaneous activity of adult male rats. Continuous exposure to 5 ppm lead produced similar effects on righting reflex development and adult spontaneous activity. The relative brain weight of F 2 neonates was decreased after lifetime parental exposure to 300 mrad/d or 5 and 50 ppm lead. Chronic lead exposure also appears to induce superovulation and increase preimplantation deaths in F 1 dams. Dose-effect responses to both HTO and lead were less than additive in their interactive effects on the parameters measured. (author)

  7. Current leads for superconducting solenoids in a transportable Dewar flask for currents up to 1kA

    International Nuclear Information System (INIS)

    Shirshov, L.S.

    1981-01-01

    A simple design of the current lead for currents up to 1 kA into a transportable helium dewar with 22 mm neck diameter is described. The lead characteristics have been studied at various conditions. Examples of pulse superconducting solenoid usage, parmitting to achieve the magnetic field up to 3.3 T are given. The 1% field homogeneity has been obtained on a length of 90 mm [ru

  8. Exposure to Sexual Stimuli Induces Greater Discounting Leading to Increased Involvement in Cyber Delinquency Among Men.

    Science.gov (United States)

    Cheng, Wen; Chiou, Wen-Bin

    2018-02-01

    People frequently encounter sexual stimuli during Internet use. Research has shown that stimuli inducing sexual motivation can lead to greater impulsivity in men, as manifested in greater temporal discounting (i.e., a tendency to prefer smaller, immediate gains to larger, future ones). Extant findings in crime research suggest that delinquents tend to focus on short-term gains while failing to adequately think through the longer-term consequences of delinquent behavior. We experimentally tested the possibility that exposure to sexual stimuli is associated with the tendency to engage in cyber delinquency among men, as a result of their overly discounting remote consequences. In Experiment 1, participants exposed to pictures of "sexy" women were more likely to discount the future and were more inclined to make cyber-delinquent choices (e.g., cyberbullying, cyber fraud, cyber theft, and illegal downloading), compared with male participants who rated the sex appeal of less sexy opposite-sex pictures. However, these relationships were not observed in female participants exposed to either highly or less sexy pictures of men. In Experiment 2, male participants exposed to sexual primes showed a greater willingness to purchase a wide range of counterfeit rather than authentic products online and experienced a higher likelihood of logging into the other person's Facebook webpage (i.e., invading online privacy). The discounting tendency mediated the link between exposure to sexual primes and the inclination to engage in cyber-delinquent behavior. These findings provide insight into a strategy for reducing men's involvement in cyber delinquency; that is, through less exposure to sexual stimuli and promotion of delayed gratification. The current results suggest that the high availability of sexual stimuli in cyberspace may be more closely associated with men's cyber-delinquent behavior than previously thought.

  9. Criterion for burn-up conditions in gas-cooled cryogenic current leads

    International Nuclear Information System (INIS)

    Bejan, A.; Cluss, E.M. Jr.

    1976-01-01

    Superconducting magnets are energized through helium vapour-cooled cryogenic current leads operating at high ratios of current to mass flow. The high current operation where lead temperature, runaway, and eventual burn-up are likely to occur is investigated. A simple criterion for estimating the burn-up operation conditions (current, mass flow) for a given lead geometry (cross-sectional area, length, heat exchanger area) is presented. This article stresses the role played by the available heat exchanger area in avoiding burn-up at high ratios of current to mass flow. (author)

  10. The relationship between blood lead levels and occupational exposure in a pregnant population.

    Science.gov (United States)

    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.

  11. The relationship between blood lead levels and occupational exposure in a pregnant population

    Directory of Open Access Journals (Sweden)

    Osmel La-Llave-León

    2016-12-01

    Full Text Available Abstract Background 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. Methods 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. Results 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. Conclusions 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.

  12. Performance of bismuth tape current leads under vibration; Bi tepu sei denryu rido no shindo tokusei

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, E.; Kurihara, M. [Railway Techniical Research Institute, Tokyo (Japan)

    2000-02-25

    The superconducting magnets on Maglev vehicles when running vibrate mechanically due to electromagnetic disturbance from the ground coils. Therefore, the current leads fixed on the superconducting coil, which is vibration at about 98 m/s{sup 2} (=10g), are also required to endure the vibration. We executed dynamic vibration tests for two types of current leads (straight and arc types) which had a multi-stacked configuration of Ag-sheathed Bi2223 tapes impregnated with epoxy resin in a concaved reinforcing gutter. We evaluated the straight-type lead for an operating current of 700 A after every vibration test in liquid nitrogen for one hour under the dynamic strain deformation of 50-100 {mu} on the surface of the reinforcing material covering the current lead. We could not detect degradation of the current lead by vibration through the total cycles of 3.9 x 10{sup 6} after continuous vibration tests. We also executed vibration tests for arc-type current leads which were combined with an actual energized superconducting coil for a Maglev. Large accelerations of these current leads occurred at frequencies of 308 and 375 Hz. In spite of the maximum acceleration of 600-700 m/s{sup 2} generated by actuating the excessive force on a superconducting coil for two seconds, which occurred on these current leads carrying 500 A, the superconductivity of the current leads did not shift to normal conductivity. There was no damage to either type of current lead during these vibration tests. So we confirmed the good prospect for the application of these current leads to actual Maglev superconducting magnets. (author)

  13. Inhibition of cardiac sodium currents by toluene exposure

    Science.gov (United States)

    Cruz, Silvia L; Orta-Salazar, Gerardo; Gauthereau, Marcia Y; Millan-Perez Peña, Lourdes; Salinas-Stefanón, Eduardo M

    2003-01-01

    Toluene is an industrial solvent widely used as a drug of abuse, which can produce sudden sniffing death due to cardiac arrhythmias. In this paper, we tested the hypothesis that toluene inhibits cardiac sodium channels in Xenopus laevis oocytes transfected with Nav1.5 cDNA and in isolated rat ventricular myocytes. In oocytes, toluene inhibited sodium currents (INa+) in a concentration-dependent manner, with an IC50 of 274 μM (confidence limits: 141–407μM). The inhibition was complete, voltage-independent, and slowly reversible. Toluene had no effect on: (i) the shape of the I–V curves; (ii) the reversal potential of Na+; and (iii) the steady-state inactivation. The slow recovery time constant from inactivation of INa+ decreased with toluene exposure, while the fast recovery time constant remained unchanged. Block of INa+ by toluene was use- and frequency-dependent. In rat cardiac myocytes, 300 μM toluene inhibited the sodium current (INa+) by 62%; this inhibition was voltage independent. These results suggest that toluene binds to cardiac Na+ channels in the open state and unbinds either when channels move between inactivated states or from an inactivated to a closed state. The use- and frequency-dependent block of INa+ by toluene might be responsible, at least in part, for its arrhythmogenic effect. PMID:14534149

  14. Effect of lead exposure on the immune response of some occupationally exposed individuals

    International Nuclear Information System (INIS)

    Mishra, Kamla Prasad; Singh, Vijay Kumar; Rani, Reena; Yadav, Virendra Singh; Chandran, Vinod; Srivastava, Satya Prakash; Seth, Prahlad Kishore

    2003-01-01

    Lead is a ubiquitous pollutant in the industrial environment, which poses serious threats to human health. In the past 20 years increasing attention has been paid to the effects of lead exposure on health. This toxic metal alters the immune response of animals as well as humans. To study the immunological effects of occupational exposure to lead, we examined lymphocyte proliferation, natural killer (NK) cell cytotoxicity and interferon-γ production with peripheral blood mononuclear cells (PBMCs) of individuals occupationally exposed to lead. We selected three different groups of individuals exposed to lead: three-wheeler drivers (30), battery workers (34) and silver jewelery makers (20); and unexposed healthy volunteers (30) as control for comparison. Our results indicate that though lymphocyte proliferation to phytohaemagglutinin (PHA) is inhibited in lead exposed individuals as compared with unexposed volunteers, there is no correlation between inhibition of lymphocyte proliferation and blood lead level. NK cell cytotoxicity remains unaffected in individuals exposed to lead as compared with controls. On the other hand, we observed that interferon-γ (IFN-γ) was significantly elevated in T cell mitogen, PHA, stimulated PBMCs culture supernatant of lead exposed individuals. We found significant positive correlation between blood lead levels and IFN-γ produced in culture supernatant on stimulation with PHA. In brief, this study demonstrates that lead can affect the immune response of the occupationally exposed individuals such as three-wheeler drivers, battery reconditioning workers and silver jewelery makers

  15. Lead exposure via drinking water - unnecessary and avoidable; Bleiexposition ueber das Trinkwasser - unnoetig und vermeidbar

    Energy Technology Data Exchange (ETDEWEB)

    Wilhelm, M. [Univ. Bochum (Germany). Abt. Hygiene, Sozial- und Umweltmedizin; Dieter, H.H. [Umweltbundesamt, Berlin (Germany). Inst. fuer Wasser-, Boden-, Lufthygiene

    2003-07-01

    Despite successful reduction of the general lead exposure, this heavy metal is still a matter of public concern due to the fact that associations with intellectual impairment or delayed puberty are found to correlate with very low lead blood concentrations. Lead in tap water is still an important contribution to lead exposure which may cause health risk for infants. Therefore, lead pipes should be completely sanitated by exchange against pipes made from more healthy materials. (orig.) [German] Trotz erfolgreicher Reduktion der allgemeinen Belastung ist Blei auch heute noch umweltmedizinisch relevant, weil es moeglicherweise bei niedrigeren als bisher angenommenen Belastungen gesundheitlich nachteilige Wirkungen, insbesondere waehrend der fruehkindlichen Entwicklung des Nervensystems, ausloest. Insbesondere Blei aus bleiernen Trinkwasserleitungen ist eine Belastung, die fuer Saeuglinge und Kleinkinder nach wie vor ein gesundheitliches Risiko darstellen kann. Solche Leitungen sollten deswegen durch Austausch gegen gesundheitlich besser geeignete Materialien saniert werden. (orig.)

  16. High temperature superconducting current lead test facility with heat pipe intercepts

    International Nuclear Information System (INIS)

    Blumenfeld, P.E.; Prenger, C.; Roth, E.W.; Stewart, J.A.

    1998-01-01

    A high temperature superconducting (HTS) current lead test facility using heat pipe thermal intercepts is under development at the Superconducting Technology Center at Los Alamos National Laboratory. The facility can be configured for tests at currents up to 1,000 A. Mechanical cryocoolers provide refrigeration to the leads. Electrical isolation is maintained by intercepting thermal energy from the leads through cryogenic heat pipes. HST lead warm end temperature is variable from 65 K to over 90 K by controlling heat pipe evaporator temperature. Cold end temperature is variable up to 30 K. Performance predictions in terms of heat pipe evaporator temperature as a function of lead current are presented for the initial facility configuration, which supports testing up to 200 A. Measurements are to include temperature and voltage gradient in the conventional and HTS lead sections, temperature and heat transfer rate in the heat pipes. as well as optimum and off-optimum performance of the conventional lead sections

  17. Exploring the Safety Margin in Current Guidelines for Electromagnetic Exposure

    NARCIS (Netherlands)

    F. Adibzadeh (Fatemeh)

    2017-01-01

    markdownabstractExposure to radio-frequency (RF) electromagnetic fields (EMF) is unavoidable in today's modern life. This exposure is growing mainly because of rapid growth in telecommunication systems. Awareness of the possible risks of exposure to EMF has raised public concern. To avoid any

  18. Human lead exposure in a late 19th century mental asylum population

    Energy Technology Data Exchange (ETDEWEB)

    Bower, Nathan W. [Department of Chemistry, Colorado College, Colorado Springs, CO 80903-3294 (United States)]. E-mail: nbower@coloradocollege.edu; McCants, Sarah A. [Department of Chemistry, Colorado College, Colorado Springs, CO 80903-3294 (United States); Custodio, Joseph M. [Department of Chemistry, Colorado College, Colorado Springs, CO 80903-3294 (United States); Ketterer, Michael E. [Departments of Chemistry and Biochemistry, Northern Arizona University, Flagstaff, AZ 86011-5698 (United States); Getty, Stephen R. [Biological Sciences Curriculum Study, Colorado Springs, CO 80918 (United States); Hoffman, J. Michael [Department of Anthropology, Colorado College, Colorado Springs, CO 8090-3294 (United States)

    2007-01-01

    Lead isotope ratios and lead (Pb) levels were analyzed in 33 individuals from a forgotten cemetery at the Colorado Mental Health Institute at Pueblo, Colorado dating to 1879-1899. Isotopic ratios from healing bone fractures, cortical bone, and tooth dentine provide information about sources of Pb exposures over a range of time that illuminates individual's life histories and migration patterns. Historical records and Pb production data from the 19th century were used to create a database for interpreting Pb exposures for these African, Hispanic and European Americans. The analysis of these individuals suggests that Pb exposure noticeably impacted the mental health of 5-10% of the asylum patients in this frontier population, a high number by standards today, and that differences exist in the three ancestral groups' exposure histories.

  19. Human lead exposure in a late 19th century mental asylum population

    International Nuclear Information System (INIS)

    Bower, Nathan W.; McCants, Sarah A.; Custodio, Joseph M.; Ketterer, Michael E.; Getty, Stephen R.; Hoffman, J. Michael

    2007-01-01

    Lead isotope ratios and lead (Pb) levels were analyzed in 33 individuals from a forgotten cemetery at the Colorado Mental Health Institute at Pueblo, Colorado dating to 1879-1899. Isotopic ratios from healing bone fractures, cortical bone, and tooth dentine provide information about sources of Pb exposures over a range of time that illuminates individual's life histories and migration patterns. Historical records and Pb production data from the 19th century were used to create a database for interpreting Pb exposures for these African, Hispanic and European Americans. The analysis of these individuals suggests that Pb exposure noticeably impacted the mental health of 5-10% of the asylum patients in this frontier population, a high number by standards today, and that differences exist in the three ancestral groups' exposure histories

  20. [Assessment for effect of low level lead-exposure on neurobehavior in workers of printing house].

    Science.gov (United States)

    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.

  1. Potential Hazard to Human Health from Exposure to Fragments of Lead Bullets and Shot in the Tissues of Game Animals

    Science.gov (United States)

    Pain, Deborah J.; Cromie, Ruth L.; Newth, Julia; Brown, Martin J.; Crutcher, Eric; Hardman, Pippa; Hurst, Louise; Mateo, Rafael; Meharg, Andrew A.; Moran, Annette C.; Raab, Andrea; Taggart, Mark A.; Green, Rhys E.

    2010-01-01

    Background Lead is highly toxic to animals. Humans eating game killed using lead ammunition generally avoid swallowing shot or bullets and dietary lead exposure from this source has been considered low. Recent evidence illustrates that lead bullets fragment on impact, leaving small lead particles widely distributed in game tissues. Our paper asks whether lead gunshot pellets also fragment upon impact, and whether lead derived from spent gunshot and bullets in the tissues of game animals could pose a threat to human health. Methodology/Principal Findings Wild-shot gamebirds (6 species) obtained in the UK were X-rayed to determine the number of shot and shot fragments present, and cooked using typical methods. Shot were then removed to simulate realistic practice before consumption, and lead concentrations determined. Data from the Veterinary Medicines Directorate Statutory Surveillance Programme documenting lead levels in raw tissues of wild gamebirds and deer, without shot being removed, are also presented. Gamebirds containing ≥5 shot had high tissue lead concentrations, but some with fewer or no shot also had high lead concentrations, confirming X-ray results indicating that small lead fragments remain in the flesh of birds even when the shot exits the body. A high proportion of samples from both surveys had lead concentrations exceeding the European Union Maximum Level of 100 ppb w.w. (0.1 mg kg−1 w.w.) for meat from bovine animals, sheep, pigs and poultry (no level is set for game meat), some by several orders of magnitude. High, but feasible, levels of consumption of some species could result in the current FAO/WHO Provisional Weekly Tolerable Intake of lead being exceeded. Conclusions/Significance The potential health hazard from lead ingested in the meat of game animals may be larger than previous risk assessments indicated, especially for vulnerable groups, such as children, and those consuming large amounts of game. PMID:20436670

  2. Potential hazard to human health from exposure to fragments of lead bullets and shot in the tissues of game animals.

    Directory of Open Access Journals (Sweden)

    Deborah J Pain

    Full Text Available BACKGROUND: Lead is highly toxic to animals. Humans eating game killed using lead ammunition generally avoid swallowing shot or bullets and dietary lead exposure from this source has been considered low. Recent evidence illustrates that lead bullets fragment on impact, leaving small lead particles widely distributed in game tissues. Our paper asks whether lead gunshot pellets also fragment upon impact, and whether lead derived from spent gunshot and bullets in the tissues of game animals could pose a threat to human health. METHODOLOGY/PRINCIPAL FINDINGS: Wild-shot gamebirds (6 species obtained in the UK were X-rayed to determine the number of shot and shot fragments present, and cooked using typical methods. Shot were then removed to simulate realistic practice before consumption, and lead concentrations determined. Data from the Veterinary Medicines Directorate Statutory Surveillance Programme documenting lead levels in raw tissues of wild gamebirds and deer, without shot being removed, are also presented. Gamebirds containing > or =5 shot had high tissue lead concentrations, but some with fewer or no shot also had high lead concentrations, confirming X-ray results indicating that small lead fragments remain in the flesh of birds even when the shot exits the body. A high proportion of samples from both surveys had lead concentrations exceeding the European Union Maximum Level of 100 ppb w.w. (0.1 mg kg(-1 w.w. for meat from bovine animals, sheep, pigs and poultry (no level is set for game meat, some by several orders of magnitude. High, but feasible, levels of consumption of some species could result in the current FAO/WHO Provisional Weekly Tolerable Intake of lead being exceeded. CONCLUSIONS/SIGNIFICANCE: The potential health hazard from lead ingested in the meat of game animals may be larger than previous risk assessments indicated, especially for vulnerable groups, such as children, and those consuming large amounts of game.

  3. Potential hazard to human health from exposure to fragments of lead bullets and shot in the tissues of game animals.

    Science.gov (United States)

    Pain, Deborah J; Cromie, Ruth L; Newth, Julia; Brown, Martin J; Crutcher, Eric; Hardman, Pippa; Hurst, Louise; Mateo, Rafael; Meharg, Andrew A; Moran, Annette C; Raab, Andrea; Taggart, Mark A; Green, Rhys E

    2010-04-26

    Lead is highly toxic to animals. Humans eating game killed using lead ammunition generally avoid swallowing shot or bullets and dietary lead exposure from this source has been considered low. Recent evidence illustrates that lead bullets fragment on impact, leaving small lead particles widely distributed in game tissues. Our paper asks whether lead gunshot pellets also fragment upon impact, and whether lead derived from spent gunshot and bullets in the tissues of game animals could pose a threat to human health. Wild-shot gamebirds (6 species) obtained in the UK were X-rayed to determine the number of shot and shot fragments present, and cooked using typical methods. Shot were then removed to simulate realistic practice before consumption, and lead concentrations determined. Data from the Veterinary Medicines Directorate Statutory Surveillance Programme documenting lead levels in raw tissues of wild gamebirds and deer, without shot being removed, are also presented. Gamebirds containing > or =5 shot had high tissue lead concentrations, but some with fewer or no shot also had high lead concentrations, confirming X-ray results indicating that small lead fragments remain in the flesh of birds even when the shot exits the body. A high proportion of samples from both surveys had lead concentrations exceeding the European Union Maximum Level of 100 ppb w.w. (0.1 mg kg(-1) w.w.) for meat from bovine animals, sheep, pigs and poultry (no level is set for game meat), some by several orders of magnitude. High, but feasible, levels of consumption of some species could result in the current FAO/WHO Provisional Weekly Tolerable Intake of lead being exceeded. The potential health hazard from lead ingested in the meat of game animals may be larger than previous risk assessments indicated, especially for vulnerable groups, such as children, and those consuming large amounts of game.

  4. Prenatal exposure to lead in Spain: cord blood levels and associated factors.

    Science.gov (United States)

    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.

  5. The astonishingly holistic role of urban soil in the exposure of children to lead.

    Science.gov (United States)

    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

  6. Diagnostic use of blood porphyrin and radiographic changes in lead exposure in goats

    International Nuclear Information System (INIS)

    Swarup, D.; Maiti, S.K.; Dwivedi, S.K.

    1990-01-01

    Blood porphyrin, hematological examination and radiographic changes were evaluated for the detection of lead intoxication in goats given daily po doses of 10, 15 and 20 mg lead acetate (5.43, 8.15 and 10.86 mg lead)/kg body weight for 30, 30 and 31 days, or a total of 91 days. Blood porphyrin was found a sensitive indicator with direct correlation (r = 0.976) to blood lead concentration. Basophilic stippling was not seen in the lead-exposed goats. Radiopaque bands developed at the distal metaphysis of the radius in 7 of the 12 lead-exposed goats at day 30. The usefulness of this sign for the diagnosis of lead exposure in goats requires further investigation

  7. Thermal conductivity measurement of HTS tapes and stacks for current lead applications

    International Nuclear Information System (INIS)

    Schwarz, Michael; Weiss, Klaus-Peter; Heller, Reinhard; Fietz, Walter H.

    2009-01-01

    The use of high-temperature-superconductors (HTS) within current leads offers a high potential to save cooling-power. The principle of HTS current leads is well established, e.g. for particle accelerators (LHC-CERN) but also on the commercial sector, which offer HTS current leads ready for use in small scale magnets and magnets systems. Future fusion machines currently under construction like ITER, W7-X or JT-60SA also will use HTS current leads. At the moment the standard material for HTS current leads is a Bi 2 Sr 2 Ca 2 Cu 3 O x (BSCCO)-AgAu composite tape. The common way to receive high current capacity current leads is to form stacks by sintering or soldering these tapes together. The solder changes the thermal conductivity of the stacks compared to the single tape in the temperature range from 4 K to 60 K. To estimate the heat flux from the warm environment to the cold application the measurement of the thermal conductivity of the soldered stack is mandatory. Therefore the thermal conductivity of stacks with different number of tapes is investigated. To measure the thermal conduction in the current flow direction, the axial heat flow method is used. Combining these results with FEM simulations gives the possibility to estimate the thermal conductivity normal to the flat tape plane. The resulting anisotropic thermal conductivity can be used to model the behaviour of the HTS tape under thermal disturbances more accurately.

  8. The analysis of QT interval and repolarization morphology of the heart in chronic exposure to lead.

    Science.gov (United States)

    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 (PbB mean ) calculated based on a series of measurements performed during 5-year observation period (35 µg/dl) into two subgroups: low exposure (LE, PbB mean = 20.0-35.0 µg/dl) and high exposure (HE, PbB mean = 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.

  9. A Low Heat Inleak Cryogenic Station for Testing HTS Current Leads for the Large Hadron Collider

    CERN Document Server

    Ballarino, A; Gomes, P; Métral, L; Serio, L; Suraci, A

    1999-01-01

    The LHC will be equipped with about 8000 superconducting magnets of all types. The total current to be transported into the cryogenic enclosure amounts to some 3360 kA. In order to reduce the heat load into the liquid helium, CERN intends to use High Temperature Superconducting (HTS) material for leads having current ratings up to 13 kA. The resistive part of the leads is cooled by forced flow of gaseous helium between 20 K and 300 K. The HTS part of the lead is immersed in a 4.5 K liquid helium bath, operates in self cooling conditions and is hydraulically separated from the resistive part. A cryogenic test station has been designed and built in order to assess the thermal and electrical performances of 13 kA prototype current leads. We report on the design, commissioning and operation of the cryogenic test station and illustrate its performance by typical test results of HTS current leads.

  10. Conceptual design of current lead for large scale high temperature superconducting rotating machine

    International Nuclear Information System (INIS)

    Le, T. D.; Kim, J. H.; Park, S. I.; Kim, H. M.

    2014-01-01

    High-temperature superconducting (HTS) rotating machines always require an electric current of from several hundreds to several thousand amperes to be led from outside into cold region of the field coil. Heat losses through the current leads then assume tremendous importance. Consequently, it is necessary to acquire optimal design for the leads which would achieve minimum heat loss during operation of machines for a given electrical current. In this paper, conduction cooled current lead type of 10 MW-Class HTS rotating machine will be chosen, a conceptual design will be discussed and performed relied on the least heat lost estimation between conventional metal lead and partially HTS lead. In addition, steady-state thermal characteristic of each one also is considered and illustrated.

  11. Low-level lead exposure effects on spatial reference memory and working memory in rats

    Institute of Scientific and Technical Information of China (English)

    Xinhua Yang; Ping Zhou; Yonghui Li

    2009-01-01

    BACKGROUND: Studies have demonstrated that lead exposure can result in cognitive dysfunction and behavior disorders. However, lead exposure impairments vary under different experimental conditions.OBJECTIVE: To detect changes in spatial learning and memory following low-level lead exposure in rats, in Morris water maze test under the same experimental condition used to analyze lead exposure effects on various memory types and learning processes.DESIGN AND SETTING: The experiment was conducted at the Animal Laboratory, Institute of Psychology, Chinese Academy of Science between February 2005 and March 2006. One-way analysis of variance (ANOVA) and behavioral observations were performed.MATERIALS: Sixteen male, healthy, adult, Sprague Dawley rats were randomized into normal control and lead exposure groups (n = 8).METHODS: Rats in the normal control group were fed distilled water, and those in the lead exposure group were fed 250 mL of 0.05% lead acetate once per day. At day 28, all rats performed the Morris water maze test, consisting of four phases: space navigation, probe test, working memory test, and visual cue test.MAIN OUTCOME MEASURES: Place navigation in the Morris water maze was used to evaluate spatial learning and memory, probe trials for spatial reference memory, working memory test for spatial working memory, and visual cue test for non-spatial cognitive function. Perkin-Elmer Model 300 Atomic Absorption Spectrometer was utilized to determine blood lead levels in rats.RESULTS: (1) In the working memory test, the time to reach the platform remained unchanged between the control and lead exposure groups (F(1,1) = 0.007, P = 0.935). A visible decrease in escape latencies was observed in each group (P = 0.028). However, there was no significant difference between the two groups (F(1,1) = 1.869, P = 0.193). The working memory probe test demonstrated no change between the two groups in the time spent in the target quadrant during the working memory probe test

  12. Hemograms for and nutritional condition of migrant bald eagles tested for exposure to lead.

    Science.gov (United States)

    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 = 66) during antumn migration, 1994-95 at Galloway Bay (Saskatchewan, Canada), for the purposes of estimating prevalence of exposure to lead. Sex and age differences in hematocrit and plasma proteins were not observed; however, female eagles exhibited larger median absolute heterophil counts than males. Hematologic values were similar to those previously reported from eagles in captivity. Departures from expected hematological values from a healthy population of eagles were not observed in birds with elevated levels of blood lead (> or =0.200 microg/ml). Similarly, nutritional condition was not related to blood-lead concentrations. Therefore, it appears that lead exposure in this population was below a threshold required to indicate toxicological alteration in the hematological values and index of nutritional condition that we measured.

  13. Design of a high-temperature superconductor current lead for electric utility SMES

    International Nuclear Information System (INIS)

    Niemann, R.C.; Cha, Y.S.; Hull, J.R.; Rey, C.M.; Dixon, K.D.

    1995-01-01

    Current leads that rely on high-temperature superconductors (HTSs) to deliver power to devices operating at liquid helium temperature have the potential to reduce refrigeration requirements to levels significantly below those achievable with conventional leads. The design of HTS current leads suitable for use in near-term superconducting magnetic energy storage (SMES) is in progress. The SMES system has an 0.5 MWh energy capacity and a discharge power of 30 MW. Lead-design considerations include safety and reliability, electrical and thermal performance, structural integrity, manufacturability, and cost. Available details of the design, including materials, configuration, and performance predictions, are presented

  14. Acute exposure to lead increases myocardial contractility independent of hypertension development

    International Nuclear Information System (INIS)

    Fioresi, M.; Furieri, L.B.; Simões, M.R.; Ribeiro, R.F. Junior; Meira, E.F.; Fernandes, A.A.; Stefanon, I.; Vassallo, D.V.

    2013-01-01

    We studied the effects of the acute administration of small doses of lead over time on hemodynamic parameters in anesthetized rats to determine if myocardial contractility changes are dependent or not on the development of hypertension. Male Wistar rats received 320 µg/kg lead acetate iv once, and their hemodynamic parameters were measured for 2 h. Cardiac contractility was evaluated in vitro using left ventricular papillary muscles as were Na + ,K + -ATPase and myosin Ca 2+ -ATPase activities. Lead increased left- (control: 112 ± 3.7 vs lead: 129 ± 3.2 mmHg) and right-ventricular systolic pressures (control: 28 ± 1.2 vs lead: 34 ± 1.2 mmHg) significantly without modifying heart rate. Papillary muscles were exposed to 8 µM lead acetate and evaluated 60 min later. Isometric contractions increased (control: 0.546 ± 0.07 vs lead: 0.608 ± 0.06 g/mg) and time to peak tension decreased (control: 268 ± 13 vs lead: 227 ± 5.58 ms), but relaxation time was unchanged. Post-pause potentiation was similar between groups (n = 6 per group), suggesting no change in sarcoplasmic reticulum activity, evaluated indirectly by this protocol. After 1-h exposure to lead acetate, the papillary muscles became hyperactive in response to a β-adrenergic agonist (10 µM isoproterenol). In addition, post-rest contractions decreased, suggesting a reduction in sarcolemmal calcium influx. The heart samples treated with 8 µM lead acetate presented increased Na + ,K + -ATPase (approximately 140%, P < 0.05 for control vs lead) and myosin ATPase (approximately 30%, P < 0.05 for control vs lead) activity. Our results indicated that acute exposure to low lead concentrations produces direct positive inotropic and lusitropic effects on myocardial contractility and increases the right and left ventricular systolic pressure, thus potentially contributing to the early development of hypertension

  15. Chronic exposure to low-levels of lead in the rat: biochemical and behavioural changes

    International Nuclear Information System (INIS)

    Rossouw, J.

    1987-01-01

    The prevalence of lead in the environment is a cause of continuing toxicology concern and there have been numerous human and animal studies to examine more thoroughly the possible consequences of exposure to this ecotoxicant. Because lead is highly toxic to the developing central nervous system, increasing concern over the rise in the lead content in the environment has been expressed. These concerns seem appropriate since more recent clinical studies have shown that prolonged exposure of children to so called 'subclinical' concentrations of lead may be associated with behavioural disorders, learning disabilities and mental retardation. Moreover, animal studies have shown that chronic perinatal low-level lead exposure elicits alterations in both learned and spontaneous behavioural patterns in the absence of typical outward signs of lead-induced neurological toxicity. No study however could relate behavioural changes to specific alterations in neurochemisty. The aim of this study was therefore to expose rats, in different stages of their development, to low-levels of lead in order to induce behavioural disorders and correlate latter with possible neurochemical changes. In accordance with the general aims of the study, the structuring of the thesis is as follows: (a) a discussion of the neurotransmitters in the brain in order to describe the different systems which have been investigated; (b) a review of appropriate literature regarding the kinetics, toxodynamics and neurotoxicity of lead and (c) a summary of the methods employed in the study. The following results are presented: (d) the effects of lead treatment on physical development of the rats; (e) the induction of behavioural supersensitivity and (f) the effects lead has on central receptors

  16. Incidence of nephrolithiasis in relation to environmental exposure to lead and cadmium in a population study

    Energy Technology Data Exchange (ETDEWEB)

    Hara, Azusa; Yang, Wen-Yi; Petit, Thibault; Zhang, Zhen-Yu; Gu, Yu-Mei; Wei, Fang-Fei; Jacobs, Lotte [Studies Coordinating Centre, Research Unit Hypertension and Cardiovascular Epidemiology, KU Leuven Department of Cardiovascular Sciences, University of Leuven, Leuven (Belgium); Odili, Augustine N. [Studies Coordinating Centre, Research Unit Hypertension and Cardiovascular Epidemiology, KU Leuven Department of Cardiovascular Sciences, University of Leuven, Leuven (Belgium); Department of Internal Medicine, Faculty of Clinical Sciences, College of Health Sciences University of Abuja (Nigeria); Thijs, Lutgarde [Studies Coordinating Centre, Research Unit Hypertension and Cardiovascular Epidemiology, KU Leuven Department of Cardiovascular Sciences, University of Leuven, Leuven (Belgium); Nawrot, Tim S. [Centre for Environmental Sciences, University of Hasselt (Belgium); Staessen, Jan A., E-mail: jan.staessen@med.kuleuven.be [Studies Coordinating Centre, Research Unit Hypertension and Cardiovascular Epidemiology, KU Leuven Department of Cardiovascular Sciences, University of Leuven, Leuven (Belgium); R& D Group VitaK, Maastricht University, Maastricht (Netherlands)

    2016-02-15

    Whether environmental exposure to nephrotoxic agents that potentially interfere with calcium homeostasis, such as lead and cadmium, contribute to the incidence of nephrolithiasis needs further clarification. We investigated the relation between nephrolithiasis incidence and environmental lead and cadmium exposure in a general population. In 1302 participants randomly recruited from a Flemish population (50.9% women; mean age, 47.9 years), we obtained baseline measurements (1985–2005) of blood lead (BPb), blood cadmium (BCd), 24-h urinary cadmium (UCd) and covariables. We monitored the incidence of kidney stones until October 6, 2014. We used Cox regression to calculate multivariable-adjusted hazard ratios for nephrolithiasis. At baseline, geometric mean BPb, BCd and UCd was 0.29 µmol/L, 9.0 nmol/L, and 8.5 nmol per 24 h, respectively. Over 11.5 years (median), nephrolithiasis occurred in 40 people. Contrasting the low and top tertiles of the distributions, the sex- and age-standardized rates of nephrolithiasis expressed as events per 1000 person-years were 0.68 vs. 3.36 (p=0.0016) for BPb, 1.80 vs. 3.28 (p=0.11) for BCd, and 1.65 vs. 2.95 (p=0.28) for UCd. In continuous analysis, with adjustments applied for sex, age, serum magnesium, and 24-h urinary volume and calcium, the hazard ratios expressing the risk associated with a doubling of the exposure biomarkers were 1.35 (p=0.015) for BPb, 1.13 (p=0.22) for BCd, and 1.23 (p=0.070) for UCd. In conclusion, our results suggest that environmental lead exposure is a risk factor for nephrolithiasis in the general population. - Highlights: • Prevalence and incidence rates of nephrolithiasis are increasing worldwide. • Lead and cadmium interfere with calcium homeostasis and might cause nephrolithiasis. • Environmental exposure to lead, not cadmium, predicts nephrolithiasis in the population. • Safety standards for environmental lead exposure need to account for nephrolithiasis. • Reducing environmental

  17. Excretion of lead and its biological activity several years after termination of exposure

    Science.gov (United States)

    Přerovská, I.; Teisinger, J.

    1970-01-01

    Přerovská, and Teisinger, J. (1970).Brit. J. industr. Med.,27, 352-355. Excretion of lead and its biological activity several years after termination of exposure. A group of 27 persons who had been treated some years previously for chronic lead poisoning at our clinic, and who had not come into occupational contact with lead since, was examined. Half of them had had no occupational exposure to lead for 3 to 5 years and the others for 8 to 17 years. In most of these persons there is still an increased lead excretion, originating from an increased deposit in the bones. The mobilization test after calcium versenate (CaEDTA) injection was greater than 0·350 mg/24 hours. The values found for haemoglobin, punctate basophilia, coproporphyrin and ALA in urine were normal, but there was, in all cases, a decreased ALA-D activity. This finding suggests biological activity of such negligible lead flow many years after termination of exposure. PMID:5488694

  18. Does a concomitant exposure to lead influence unfavorably the naphthalene subchronic toxicity and toxicokinetics?

    Science.gov (United States)

    Katsnelson, Boris A; Minigaliyeva, Ilzira A; Degtyareva, Tamara D; Privalova, Larisa I; Beresneva, Tatyana A

    2014-01-01

    Rats were given 20 times during 40 d either naphthalene per gavage or the same and lead acetate intraperitoneally in single doses corresponding to 5% of the respective 50% lethal doses. The concomitant exposure to lead not only added some typical indicators of lead toxicity to the moderate naphthalene intoxication picture but also exaggerated some less specific indices for intoxication. However, a number of such indices testified to attenuation of naphthalene's adverse effects under the impact of lead. Lead also lowered urinary excretion of both total and conjugated naphthalene, while the free- to total naphthalene ratio in urine sharply increased. These results corroborate implicitly the initial hypothesis that lead, being an inhibitor of cytochrome P450, hinders phase I of the naphthalene biotransformation and, thus, the formation of derivates which can be more toxic but are capable of entering into reactions of conjugation with resulting detoxication and elimination of naphthalene from the body. © 2013 SETAC.

  19. Betel quid chewing elevates human exposure to arsenic, cadmium and lead

    Energy Technology Data Exchange (ETDEWEB)

    Al-Rmalli, Shaban W.; Jenkins, Richard O. [Faculty of Health and Life Sciences, De Montfort University, The Gateway, Leicester LE1 9BH (United Kingdom); Haris, Parvez I., E-mail: pharis@dmu.ac.uk [Faculty of Health and Life Sciences, De Montfort University, The Gateway, Leicester LE1 9BH (United Kingdom)

    2011-06-15

    Several studies have reported increased skin lesions in betel quid (a mixture of Piper betel leaves, areca nut, tobacco/flavoured tobacco, lime) chewers compared to non-chewers, exposed to arsenic (As) contaminated drinking water in Bangladesh and India. The current study has determined As, cadmium (Cd) and lead (Pb) levels of betel quids and its components using inductively coupled plasma mass spectrometry (ICP-MS). The highest concentrations of As were found in slaked lime (4.56 mg kg{sup -1}) followed by Piper betel leaves (0.406 mg kg{sup -1}) and flavoured tobacco (zarda) (0.285 mg kg{sup -1}), with a mean concentrations of As in betel quids of 0.035 mg kg{sup -1} (SD 0.02 mg kg{sup -1}). Mean concentrations of Cd and Pb in ordinary quids were 0.028 (SD 0.07 mg kg{sup -1}) and 0.423 (SD 1.4 mg kg{sup -1}), respectively. We estimated that a daily intake of 6 betel quids could contribute 1.2, 1.9 and 8.5% of the provisional maximum tolerable daily intake (PMDTI) for As, Cd and Pb, respectively. Since betel quid chewing is most prevalent among women, our finding raises concern that women chewers - especially pregnant chewers - may be harming their health and that of their unborn babies through increased exposure to a mixture of toxic elements (As, Cd and Pb).

  20. Betel quid chewing elevates human exposure to arsenic, cadmium and lead.

    Science.gov (United States)

    Al-Rmalli, Shaban W; Jenkins, Richard O; Haris, Parvez I

    2011-06-15

    Several studies have reported increased skin lesions in betel quid (a mixture of Piper betel leaves, areca nut, tobacco/flavoured tobacco, lime) chewers compared to non-chewers, exposed to arsenic (As) contaminated drinking water in Bangladesh and India. The current study has determined As, cadmium (Cd) and lead (Pb) levels of betel quids and its components using inductively coupled plasma mass spectrometry (ICP-MS). The highest concentrations of As were found in slaked lime (4.56 mg kg(-1)) followed by Piper betel leaves (0.406 mg kg(-1)) and flavoured tobacco (zarda) (0.285 mg kg(-1)), with a mean concentrations of As in betel quids of 0.035 mg kg(-1) (SD 0.02 mg kg(-1)). Mean concentrations of Cd and Pb in ordinary quids were 0.028 (SD 0.07 mg kg(-1)) and 0.423 (SD 1.4 mg kg(-1)), respectively. We estimated that a daily intake of 6 betel quids could contribute 1.2, 1.9 and 8.5% of the provisional maximum tolerable daily intake (PMDTI) for As, Cd and Pb, respectively. Since betel quid chewing is most prevalent among women, our finding raises concern that women chewers - especially pregnant chewers - may be harming their health and that of their unborn babies through increased exposure to a mixture of toxic elements (As, Cd and Pb). Copyright © 2011 Elsevier B.V. All rights reserved.

  1. Betel quid chewing elevates human exposure to arsenic, cadmium and lead

    International Nuclear Information System (INIS)

    Al-Rmalli, Shaban W.; Jenkins, Richard O.; Haris, Parvez I.

    2011-01-01

    Several studies have reported increased skin lesions in betel quid (a mixture of Piper betel leaves, areca nut, tobacco/flavoured tobacco, lime) chewers compared to non-chewers, exposed to arsenic (As) contaminated drinking water in Bangladesh and India. The current study has determined As, cadmium (Cd) and lead (Pb) levels of betel quids and its components using inductively coupled plasma mass spectrometry (ICP-MS). The highest concentrations of As were found in slaked lime (4.56 mg kg -1 ) followed by Piper betel leaves (0.406 mg kg -1 ) and flavoured tobacco (zarda) (0.285 mg kg -1 ), with a mean concentrations of As in betel quids of 0.035 mg kg -1 (SD 0.02 mg kg -1 ). Mean concentrations of Cd and Pb in ordinary quids were 0.028 (SD 0.07 mg kg -1 ) and 0.423 (SD 1.4 mg kg -1 ), respectively. We estimated that a daily intake of 6 betel quids could contribute 1.2, 1.9 and 8.5% of the provisional maximum tolerable daily intake (PMDTI) for As, Cd and Pb, respectively. Since betel quid chewing is most prevalent among women, our finding raises concern that women chewers - especially pregnant chewers - may be harming their health and that of their unborn babies through increased exposure to a mixture of toxic elements (As, Cd and Pb).

  2. Analysis of induced electrical currents from magnetic field coupling inside implantable neurostimulator leads

    Directory of Open Access Journals (Sweden)

    Seidman Seth J

    2011-10-01

    Full Text Available Abstract Background Over the last decade, the number of neurostimulator systems implanted in patients has been rapidly growing. Nearly 50, 000 neurostimulators are implanted worldwide annually. The most common type of implantable neurostimulators is indicated for pain relief. At the same time, commercial use of other electromagnetic technologies is expanding, making electromagnetic interference (EMI of neurostimulator function an issue of concern. Typically reported sources of neurostimulator EMI include security systems, metal detectors and wireless equipment. When near such sources, patients with implanted neurostimulators have reported adverse events such as shock, pain, and increased stimulation. In recent in vitro studies, radio frequency identification (RFID technology has been shown to inhibit the stimulation pulse of an implantable neurostimulator system during low frequency exposure at close distances. This could potentially be due to induced electrical currents inside the implantable neurostimulator leads that are caused by magnetic field coupling from the low frequency identification system. Methods To systematically address the concerns posed by EMI, we developed a test platform to assess the interference from coupled magnetic fields on implantable neurostimulator systems. To measure interference, we recorded the output of one implantable neurostimulator, programmed for best therapy threshold settings, when in close proximity to an operating low frequency RFID emitter. The output contained electrical potentials from the neurostimulator system and those induced by EMI from the RFID emitter. We also recorded the output of the same neurostimulator system programmed for best therapy threshold settings without RFID interference. Using the Spatially Extended Nonlinear Node (SENN model, we compared threshold factors of spinal cord fiber excitation for both recorded outputs. Results The electric current induced by low frequency RFID emitter

  3. Neural Circuits via Which Single Prolonged Stress Exposure Leads to Fear Extinction Retention Deficits

    Science.gov (United States)

    Knox, Dayan; Stanfield, Briana R.; Staib, Jennifer M.; David, Nina P.; Keller, Samantha M.; DePietro, Thomas

    2016-01-01

    Single prolonged stress (SPS) has been used to examine mechanisms via which stress exposure leads to post-traumatic stress disorder symptoms. SPS induces fear extinction retention deficits, but neural circuits critical for mediating these deficits are unknown. To address this gap, we examined the effect of SPS on neural activity in brain regions…

  4. Association of dental enamel lead levels with risk factors for environmental exposure.

    Science.gov (United States)

    Olympio, Kelly Polido Kaneshiro; Naozuka, Juliana; Oliveira, Pedro Vitoriano; Cardoso, Maria Regina Alves; Bechara, Etelvino José Henriques; Günther, Wanda Maria Risso

    2010-10-01

    To analyze household risk factors associated with high lead levels in surface dental enamel. A cross-sectional study was conducted with 160 Brazilian adolescents aged 1418 years living in poor neighborhoods in the city of Bauru, southeastern Brazil, from August to December 2008. Body lead concentrations were assessed in surface dental enamel acid-etch microbiopsies. Dental enamel lead levels were measured by graphite furnace atomic absorption spectrometry and phosphorus levels were measured by inductively coupled plasma optical emission spectrometry. The parents answered a questionnaire about their children's potential early (05 years old) exposure to well-known lead sources. Logistic regression was used to identify associations between dental enamel lead levels and each environmental risk factor studied. Social and familial covariables were included in the models. The results suggest that the adolescents studied were exposed to lead sources during their first years of life. Risk factors associated with high dental enamel lead levels were living in or close to a contaminated area (OR = 4.49; 95% CI: 1.69;11.97); and member of the household worked in the manufacturing of paints, paint pigments, ceramics or batteries (OR = 3.43; 95% CI: 1.31;9.00). Home-based use of lead-glazed ceramics, low-quality pirated toys, anticorrosive paint on gates and/or sale of used car batteries (OR = 1.31; 95% CI: 0.56;3.03) and smoking (OR = 1.66; 95% CI: 0.52;5.28) were not found to be associated with high dental enamel lead levels. Surface dental enamel can be used as a marker of past environmental exposure to lead and lead concentrations detected are associated to well-known sources of lead contamination.

  5. Association of dental enamel lead levels with risk factors for environmental exposure

    Directory of Open Access Journals (Sweden)

    Kelly Polido Kaneshiro Olympio

    2010-10-01

    Full Text Available OBJECTIVE: To analyze household risk factors associated with high lead levels in surface dental enamel. METHODS: A cross-sectional study was conducted with 160 Brazilian adolescents aged 14-18 years living in poor neighborhoods in the city of Bauru, southeastern Brazil, from August to December 2008. Body lead concentrations were assessed in surface dental enamel acid-etch microbiopsies. Dental enamel lead levels were measured by graphite furnace atomic absorption spectrometry and phosphorus levels were measured by inductively coupled plasma optical emission spectrometry. The parents answered a questionnaire about their children's potential early (05 years old exposure to well-known lead sources. Logistic regression was used to identify associations between dental enamel lead levels and each environmental risk factor studied. Social and familial covariables were included in the models. RESULTS: The results suggest that the adolescents studied were exposed to lead sources during their first years of life. Risk factors associated with high dental enamel lead levels were living in or close to a contaminated area (OR = 4.49; 95% CI: 1.69;11.97; and member of the household worked in the manufacturing of paints, paint pigments, ceramics or batteries (OR = 3.43; 95% CI: 1.31;9.00. Home-based use of lead-glazed ceramics, low-quality pirated toys, anticorrosive paint on gates and/or sale of used car batteries (OR = 1.31; 95% CI: 0.56;3.03 and smoking (OR = 1.66; 95% CI: 0.52;5.28 were not found to be associated with high dental enamel lead levels. CONCLUSIONS: Surface dental enamel can be used as a marker of past environmental exposure to lead and lead concentrations detected are associated to well-known sources of lead contamination.

  6. Prediction of burnout of a conduction-cooled BSCCO current lead

    International Nuclear Information System (INIS)

    Seol, S.Y.; Cha, Y.S.; Niemann, R.C.; Hull, J.R.

    1996-01-01

    A one-dimensional heat conduction model is employed to predict burnout of a Bi 2 Sr 2 CaCu 2 O 8 current lead. The upper end of the lead is assumed to be at 77 K and the lower end is at 4 K. The results show that burnout always occurs at the warmer end of the lead. The lead reaches its burnout temperature in two distinct stage. Initially, the temperature rises slowly when part of the lead is in flux-flow state. As the local temperature reaches the critical temperature, it begins to increase sharply. Burnout time depends strongly on flux-flow resistivity

  7. Combining Lead Exposure Measurements and Experts' Judgment Through a Bayesian Framework.

    Science.gov (United States)

    Koh, Dong-Hee; Park, Ju-Hyun; Lee, Sang-Gil; Kim, Hwan-Cheol; Choi, Sangjun; Jung, Hyejung; Park, Dong-Uk

    2017-11-10

    CARcinogen EXposure (CAREX) is a carcinogen-surveillance system employed in many countries. To develop Korean CAREX, the intensity of exposure to lead, as an example, was estimated across industries. Airborne-lead measurement records were extracted from the work-environment measurement database (WEMD), which is a nationwide workplace-monitoring database. Lead measurements were log-transformed; then, the log-transformed geometric means (LGMs) and log-transformed geometric standard deviations (LGSDs) were calculated for each industry. However, the data of many industries was limited. To address this shortcoming, experts' judgments of the lead exposure levels across industries were elicited. Experts provided their estimates of lead exposure levels as the boundary of the 5th and 95th percentiles, and it is assumed that these estimates are based on the log-normal distributions of exposure levels. Estimates of LGM and LGSD were extracted from each expert's response and then combined to quantify the experts' prior distribution. Then, the experts' prior distributions for each industry were updated with the corresponding LGMs and LGSDs calculated from the WEMD data through a Bayesian framework, yielding posterior distributions of the LGM and LGSD. The WEMD contains 83035 airborne-lead measurements that were collected between 2002 and 2007. A total of 17 occupational-hygiene professionals with >20 years of experience provided lead exposure estimates. In industries where measurement data were abundant, the measurement data dominated the posterior exposure estimates. For example, for one industry, 'Manufacture of Accumulator, Primary Cells, and Primary Batteries,' 1152 lead measurements [with a geometric mean (GM) of 14.42 µg m-3 and a geometric standard deviation (GSD) of 3.31] were available and 15 experts' responses (with a GM of 7.06 µg m-3 and a GSD of 4.15) were collected, resulting in a posterior exposure estimate of 14.41µg m-3 as the GM with a GSD of 3.31. For

  8. Cognition in children does not suffer from very low lead exposure.

    Science.gov (United States)

    Minder, B; Das-Smaal, E A; Orlebeke, J F

    1998-01-01

    We studied the relationship between exposure to lead and memory and attention in children. Participants were 313 boys aged 9 to 12 years who attended special education schools in the Netherlands. Children whose possible attentional or memory problems were obviously due to causes other than lead contamination were excluded from the study. Cognition was assessed by extensive theory- based testing. Blood lead concentration was measured to assess body lead burden. Possible confounding factors that might affect blood lead level and/or cognitive functioning were assessed. Blood lead levels were higher in children with lower socioeconomic status and in children with more hand-to-mouth behavior, and varied seasonally, with higher values in spring and summer. The mean blood lead level was 44.4 microgram lead per liter blood, which is considered low. Only 2% of the children showed a slightly higher blood lead level than the American safety standard. To obtain robust measures of cognitive aspects, we performed a factor analysis. The results showed that blood lead level did not influence any of the cognitive factors. Therefore this study, despite being designed to maximize the chance of finding an effect in asymptomatic children, does not support a relationship between lead at very low doses (below 100 micrograms/liter blood) and cognition in schoolchildren.

  9. Environmental lead exposure among primary school children in Shebin El-Kom District, Menoufiya Governorate, Egypt.

    Science.gov (United States)

    Abdel Rasoul, G M; Al-Batanony, M A; Mahrous, O A; Abo-Salem, M E; Gabr, H M

    2012-10-01

    Lead still remains an important problem for poor, inner-city, ethnic minority children, with a particular emphasis on lead paint and dust. In Egypt, there is no national survey about the prevalence of elevated blood lead level among children. To assess the environmental lead level as well as to determine blood lead level among primary school children and find out its relationship with their intelligent quotient (IQ), hemoglobin level, hearing impairment and school performance. 190 primary school children from rural and urban areas were selected and their blood lead levels (BLL), hemoglobin concentrations, IQ, hearing threshold and school performance were measured. Also, environmental lead level was measured in the school and home. The mean value of environmental lead (μg/m3) in urban schools air was significantly higher than that in rural areas. BLL had a significant negative correlation with hemoglobin level and IQ; it was positively correlated with the hearing threshold. With increasing BLL, the school performance of children decreased significantly. Exposure to lead would deteriorate IQ, school performance and hearing level of school children. Even in the absence of overt clinical manifestations of lead toxicity, lead intoxication should be among differential diagnosis in children presenting anemia, intellectual impairment, poor academic performance and hearing impairment.

  10. Maternal exposure to arsenic, cadmium, lead, and mercury and neural tube defects in offspring

    International Nuclear Information System (INIS)

    Brender, Jean D.; Suarez, Lucina; Felkner, Marilyn; Gilani, Zunera; Stinchcomb, David; Moody, Karen; Henry, Judy; Hendricks, Katherine

    2006-01-01

    Arsenic, cadmium, lead, and mercury are neurotoxins, and some studies suggest that these elements might also be teratogens. Using a case-control study design, we investigated the relation between exposure to these heavy metals and neural tube defects (NTDs) in offspring of Mexican-American women living in 1 of the 14 Texas counties bordering Mexico. A total of 184 case-women with NTD-affected pregnancies and 225 control-women with normal live births were interviewed about their environmental and occupational exposures during the periconceptional period. Biologic samples for blood lead and urinary arsenic, cadmium, and mercury were also obtained for a subset of these women. Overall, the median levels of these biomarkers for heavy metal exposure did not differ significantly (P>0.05) between case- and control-women. However, among women in the highest income group, case-women were nine times more likely (95% confidence interval (CI) 1.4-57) than control-women to have a urinary mercury >=5.62μg/L. Case-women were 4.2 times more likely (95% CI 1.1-16) to report burning treated wood during the periconceptional period than control-women. Elevated odds ratios (ORs) were observed for maternal and paternal occupational exposures to arsenic and mercury, but the 95% CIs were consistent with unity. The 95% CIs of the ORs were also consistent with unity for higher levels of arsenic, cadmium, lead, and mercury in drinking water and among women who lived within 2 miles at the time of conception to industrial facilities with reported emissions of any of these heavy metals. Our findings suggest that maternal exposures to arsenic, cadmium, or lead are probably not significant risk factors for NTDs in offspring. However, the elevated urinary mercury levels found in this population and exposures to the combustion of treated wood may warrant further investigation

  11. Experience of 12 kA / 16 V SMPS during the HTS Current Leads Test

    Science.gov (United States)

    Panchal, P.; Christian, D.; Panchal, R.; Sonara, D.; Purwar, G.; Garg, A.; Nimavat, H.; Singh, G.; Patel, J.; Tanna, V.; Pradhan, S.

    2017-04-01

    As a part of up gradation plans in SST-1 Tokamak, one pair of 3.3 kA rated prototype hybrid current leads were developed using Di-BSCCO as High Temperature Superconductors (HTS) and the copper heat exchanger. In order to validate the manufacturing procedure prior to go for series production of such current leads, it was recommended to test these current leads using dedicated and very reliable DC switch mode power supply (SMPS). As part of test facility, 12 kA, 16 VDC programmable SMPS was successfully installed, commissioned and tested. This power supply has special features such as modularity, N+1 redundancy, very low ripple voltage, precise current measurements with Direct Current Current Transformer, CC/CV modes with auto-crossover and auto-sequence programming. As a part of acceptance of this converter, A 5.8 mΩ water-cooled resistive dummy load and PLC based SCADA system is designed, developed for commissioning of power supply. The same power supply was used for the testing of the prototype HTS current leads. The paper describes the salient features and experience of state-of-art of power supply and results obtained from this converter during the HTS current leads test.

  12. HTS current lead units prepared by the TFA-MOD processed YBCO coated conductors

    International Nuclear Information System (INIS)

    Shiohara, K.; Sakai, S.; Ishii, Y.; Yamada, Y.; Tachikawa, K.; Koizumi, T.; Aoki, Y.; Hasegawa, T.; Tamura, H.; Mito, T.

    2010-01-01

    Two superconducting current lead units have been prepared using ten coated conductors of the Tri-Fluoro-Acetate - Metal Organic Deposition (TFA-MOD) processed Y 1 Ba 2 Cu 3 O 7-δ (YBCO) coated conductors with critical current (I c ) of about 170 A at 77 K in self-field. The coated conductors are 5 mm in width, 190 mm in length and about 120 μm in overall thickness. The 1.5 μm thick superconducting YBCO layer was synthesized through the TFA-MOD process on Hastelloy TM C-276 substrate tape with two buffer oxide layers of Gd 2 Zr 2 O 7 and CeO 2 . The five YBCO coated conductors are attached on a 1 mm thick Glass Fiber Reinforced Plastics (GFRP) board and soldered to Cu caps at the both ends. We prepared two 500 A-class current lead units. The DC transport current of 800 A was stably applied at 77 K without any voltage generation in all coated conductors. The voltage between both Cu caps linearly increased with increasing the applied current, and was about 350 μV at 500 A in both current lead units. According to the estimated values of the heat leakage from 77 K to 4.2 K, the heat leakage for the current lead unit was 46.5 mW. We successfully attained reduction of the heat leakage because of improvement of the transport current performance (I c ), a thinner Ag layer of YBCO coated conductor and usage of the GFRP board for reinforcement instead of a stainless steel board used in the previous study. The DC transport current of 1400 A was stably applied when the two current lead units were joined in parallel. The sum of the heat leakages from 77 K to 4.2 K for the combined the current lead units was 93 mW. In comparison with the conventional Cu current leads by gas-cooling, it could be noted that the heat leakage of the current lead is about one order of magnitude smaller than that of the Cu current lead.

  13. Chronic prenatal lead exposure impairs long-term memory in day old chicks.

    Science.gov (United States)

    Zhong, Zhaoming; Zhang, Chunxiao; Rizak, Joshua D; Cui, Yonghua; Xu, Shiqing; Che, Yi

    2010-05-26

    Environmental exposure to lead during developmental stages has been established as a potential cause of intellectual deficits. The high susceptibility of rapidly developing fetal and infant brains to external factors suggests that impairment of later cognitive functions may arise from relatively minor prenatal exposure to environmental lead levels. In this study, we used the one-trial passive avoidance learning paradigm with day old chicks to evaluate memory function and memory consolidation in response to prenatal lead exposure. Lead acetate (5.5mg/kg, 11mg/kg, 16.5mg/kg) was administered daily from E9 to E16 via direct injection into the airspace in chick eggs. Higher doses of lead acetate (11mg/kg, 16.5mg/kg) administration had significant effects on the hatching success (23.4 and 17, respectively) and hatch weight ( approximately 10% decrease) of chicks when compared to equivalent treatments of sodium acetate (11mg/kg, 16.5mg/kg) (plong-term memory after 120min following training in the one-trial passive avoidance learning task (pmemory processes. Copyright 2010 Elsevier Ireland Ltd. All rights reserved.

  14. Effects of chronic lead exposure on bone mineral properties in femurs of growing rats

    International Nuclear Information System (INIS)

    Álvarez-Lloret, Pedro; Lee, Ching Ming; Conti, María Inés; Terrizzi, Antonela Romina; González-López, Santiago; Martínez, María Pilar

    2017-01-01

    Lead exposure has been associated with several defective skeletal growth processes and bone mineral alterations. The aim of the present study is to make a more detailed description of the toxic effects of lead intoxication on bone intrinsic material properties as mineral composition, morphology and microstructural characteristics. For this purpose, Wistar rats were exposed (n = 12) to 1000 ppm lead acetate in drinking water for 90 days while control group (n = 8) were treated with sodium acetate. Femurs were examined using inductively coupled plasma optical emission spectrometry (ICP-OES), Attenuated Total Reflection Fourier transform infrared spectroscopy (ATR-FTIR), X-ray diffraction (XRD), and micro-Computed Tomography (μCT). Results showed that femur from the lead-exposed rats had higher carbonate content in bone mineral and (Ca 2+ + Mg 2+ + Na + )/P ratio values, although no variations were observed in crystal maturity and crystallite size. From morphological analyses, lead exposure rats showed a decreased in trabecular bone surface and distribution while trabecular thickness and cortical area increased. These overall effects indicate a similar mechanism of bone maturation normally associated to age-related processes. These responses are correlated with the adverse actions induced by lead on the processes regulating bone turnover mechanism. This information may explain the osteoporosis diseases associated to lead intoxication as well as the risk of fracture observed in populations exposed to this toxicant.

  15. Effects of chronic lead exposure on bone mineral properties in femurs of growing rats.

    Science.gov (United States)

    Álvarez-Lloret, Pedro; Lee, Ching Ming; Conti, María Inés; Terrizzi, Antonela Romina; González-López, Santiago; Martínez, María Pilar

    2017-02-15

    Lead exposure has been associated with several defective skeletal growth processes and bone mineral alterations. The aim of the present study is to make a more detailed description of the toxic effects of lead intoxication on bone intrinsic material properties as mineral composition, morphology and microstructural characteristics. For this purpose, Wistar rats were exposed (n=12) to 1000ppm lead acetate in drinking water for 90days while control group (n=8) were treated with sodium acetate. Femurs were examined using inductively coupled plasma optical emission spectrometry (ICP-OES), Attenuated Total Reflection Fourier transform infrared spectroscopy (ATR-FTIR), X-ray diffraction (XRD), and micro-Computed Tomography (μCT). Results showed that femur from the lead-exposed rats had higher carbonate content in bone mineral and (Ca 2+ +Mg 2+ + Na + )/P ratio values, although no variations were observed in crystal maturity and crystallite size. From morphological analyses, lead exposure rats showed a decreased in trabecular bone surface and distribution while trabecular thickness and cortical area increased. These overall effects indicate a similar mechanism of bone maturation normally associated to age-related processes. These responses are correlated with the adverse actions induced by lead on the processes regulating bone turnover mechanism. This information may explain the osteoporosis diseases associated to lead intoxication as well as the risk of fracture observed in populations exposed to this toxicant. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  16. Radiation exposure of radiologists during angiography: Dose measurements outside the lead apron

    International Nuclear Information System (INIS)

    Fischer, H.; Przetak, C.; Teubert, G.; Ewen, K.; Moedder, U.

    1995-01-01

    The aim of this study was to provide practical information to angiographers concerning radiation exposure to body parts not covered by lead aprons. Individual doses to the neck and hands of radiologists measured in micro-Sieverts were obtained during the course of 80 angiographies of various types. The number of diagnostic and interventional procedures, which might lead to exceeding permissible doses, have been calculated. Possibilities of estimating doses during angiography by means of parameters such as screening times were examined statistically. Especially with regard to the hands, estimations of the doses are insufficient (correlation r=0.21). Radiologists who undertake much angiographic and particularly interventional work may reach exposure levels requiring protective measures in addition to lead aprons. (orig.) [de

  17. Perinatal exposure to lead and cadmium affects anxiety-like behaviour

    International Nuclear Information System (INIS)

    Leret, M.Luisa; Millan, Jose Antonio San; Antonio, M.Teresa

    2003-01-01

    The present study examines the effects of early simultaneous exposure to low level of lead and cadmium on anxiety-like behaviour in the rat, and on monoamine levels in the hypothalamus and hippocampus at weaning and adult animals. Rats were intoxicated with cadmium acetate (10 mg/l) and lead acetate (300 mg/l) in drinking water from the beginning of pregnancy until weaning. Maternal co-exposure to lead and cadmium produced mainly alterations in dopaminergic and serotoninergic systems of hippocampus in both age studied, while noradrenaline content in hypothalamus and hippocampus remained unchanged at 75 days of age. The intoxicated rats showed an increased on indices of anxiety on the elevated plus-maze. These long-term changes in anxiety-like behaviour can be related to dopaminergic and serotoninergic alterations detected in hippocampus

  18. Test results of the 18 kA EDIPO HTS current leads

    International Nuclear Information System (INIS)

    Wesche, Rainer; Bagnasco, Maurizio; Bruzzone, Pierluigi; Felder, Roland; Guetg, Marc; Holenstein, Manuel; Jenni, Markus; March, Stephen; Roth, Felix; Vogel, Martin

    2011-01-01

    For the new test facility EDIPO (European DIPOle), to be hosted by CRPP, two 18 kA HTS current leads were manufactured and successfully tested. The HTS module, made of AgMgAu/Bi-2223 tapes, is cooled only by heat conduction to the cold end, while the copper part is cooled by forced flow helium gas. The current leads were tested at low voltage up to the maximum current of 18 kA. The helium mass flow rates required for stable operation at various currents were determined. In addition to the steady state operation, the transient behavior in the case of a loss of flow was studied experimentally. The test results provide an estimate of the operational limits of the EDIPO HTS current leads.

  19. Test results of the 18 kA EDIPO HTS current leads

    Energy Technology Data Exchange (ETDEWEB)

    Wesche, Rainer, E-mail: rainer.wesche@psi.ch [Ecole Polytechnique Federale de Lausanne (EPFL), Centre de Recherches en Physique des Plasmas (CRPP), Association Euratom - Confederation Suisse, 5232 Villigen PSI (Switzerland); Bagnasco, Maurizio; Bruzzone, Pierluigi; Felder, Roland; Guetg, Marc; Holenstein, Manuel; Jenni, Markus; March, Stephen; Roth, Felix; Vogel, Martin [Ecole Polytechnique Federale de Lausanne (EPFL), Centre de Recherches en Physique des Plasmas (CRPP), Association Euratom - Confederation Suisse, 5232 Villigen PSI (Switzerland)

    2011-10-15

    For the new test facility EDIPO (European DIPOle), to be hosted by CRPP, two 18 kA HTS current leads were manufactured and successfully tested. The HTS module, made of AgMgAu/Bi-2223 tapes, is cooled only by heat conduction to the cold end, while the copper part is cooled by forced flow helium gas. The current leads were tested at low voltage up to the maximum current of 18 kA. The helium mass flow rates required for stable operation at various currents were determined. In addition to the steady state operation, the transient behavior in the case of a loss of flow was studied experimentally. The test results provide an estimate of the operational limits of the EDIPO HTS current leads.

  20. Reduction of the heat leak in superconducting system at half-wave-rectified current mode by peltier current lead

    International Nuclear Information System (INIS)

    Yamaguchi, Takayuki; Ohtaki, Naohiro; Nakamura, Keiji; Yamaguchi, Satarou; Hasegawa, Yasuhiro

    2002-01-01

    Experiments of Peltier current lead (PCL) were performed by the way of half-wave-rectified current (HWRC) for an evaluation of the PCL system in the drive with the large-rippled current. The current ripple of the HWRC is large, and we discussed the cooling capability of the current ripple. The experimental results revealed that the temperature difference of the thermoelectric-element (TE) increased with the magnitude of the current in the PCL system, despite the large current ripple. Calorimetric measurements revealed that the PCL reduced the heat leak of 60% for the peak current 90A. We compared the PCL systems of the direct current (dc) mode and the HWRC mode. The results showed that the current dependence of the temperature difference in the HWRC mode did not match that of the dc mode, but those of the heat leak matched well. The performance of the Peltier cooling in the HWRC mode is reduced to be 2/π time of the Seebeck coefficient for the dc mode by using the time-average method. (author)

  1. Reduction of the heat leak in superconducting system at half-wave-rectified current mode by peltier current lead

    CERN Document Server

    Yamaguchi, T; Nakamura, K; Yamaguchi, S; Hasegawa, Y

    2002-01-01

    Experiments of Peltier current lead (PCL) were performed by the way of half-wave-rectified current (HWRC) for an evaluation of the PCL system in the drive with the large-rippled current. The current ripple of the HWRC is large, and we discussed the cooling capability of the current ripple. The experimental results revealed that the temperature difference of the thermoelectric-element (TE) increased with the magnitude of the current in the PCL system, despite the large current ripple. Calorimetric measurements revealed that the PCL reduced the heat leak of 60% for the peak current 90A. We compared the PCL systems of the direct current (dc) mode and the HWRC mode. The results showed that the current dependence of the temperature difference in the HWRC mode did not match that of the dc mode, but those of the heat leak matched well. The performance of the Peltier cooling in the HWRC mode is reduced to be 2/pi time of the Seebeck coefficient for the dc mode by using the time-average method. (author)

  2. 75 FR 80819 - Draft Current Intelligence Bulletin “Occupational Exposure to Carbon Nanotubes and Nanofibers”

    Science.gov (United States)

    2010-12-23

    ... protective equipment; (4) Current exposure measurement methods and challenges in measuring workplace exposures to carbon nanotubes and nanofibers; (5) Areas for future collaborative efforts (e.g., research... business affiliations of the presenter, topic of the presentation, and [[Page 80820

  3. Biomarkers of nanomaterial exposure and effect: current status

    Science.gov (United States)

    Iavicoli, Ivo; Leso, Veruscka; Manno, Maurizio; Schulte, Paul A.

    2014-03-01

    Recent advances in nanotechnology have induced a widespread production and application of nanomaterials. As a consequence, an increasing number of workers are expected to undergo exposure to these xenobiotics, while the possible hazards to their health remain not being completely understood. In this context, biological monitoring may play a key role not only to identify potential hazards from and to evaluate occupational exposure to nanomaterials, but also to detect their early biological effects to better assess and manage risks of exposure in respect of the health of workers. Therefore, the aim of this review is to provide a critical evaluation of potential biomarkers of nanomaterial exposure and effect investigated in human and animal studies. Concerning exposure biomarkers, internal dose of metallic or metal oxide nanoparticle exposure may be assessed measuring the elemental metallic content in blood or urine or other biological materials, whereas specific molecules may be carefully evaluated in target tissues as possible biomarkers of biologically effective dose. Oxidative stress biomarkers, such as 8-hydroxy-deoxy-guanosine, genotoxicity biomarkers, and inflammatory response indicators may also be useful, although not specific, as biomarkers of nanomaterial early adverse health effects. Finally, potential biomarkers from "omic" technologies appear to be quite innovative and greatly relevant, although mechanistic, ethical, and practical issues should all be resolved before their routine application in occupational settings could be implemented. Although all these findings are interesting, they point out the need for further research to identify and possibly validate sensitive and specific biomarkers of exposure and effect, suitable for future use in occupational biomonitoring programs. A valuable contribution may derive from the studies investigating the biological behavior of nanomaterials and the factors influencing their toxicokinetics and reactivity. In

  4. Altered miRNA expression in the cervix during pregnancy associated with lead and mercury exposure

    Science.gov (United States)

    Sanders, Alison P; Burris, Heather H; Just, Allan C; Motta, Valeria; Amarasiriwardena, Chitra; Svensson, Katherine; Oken, Emily; Solano-Gonzalez, Maritsa; Mercado-Garcia, Adriana; Pantic, Ivan; Schwartz, Joel; Tellez-Rojo, Martha M; Baccarelli, Andrea A; Wright, Robert O

    2015-01-01

    Aim: Toxic metals including lead and mercury are associated with adverse pregnancy outcomes. This study aimed to assess the association between miRNA expression in the cervix during pregnancy with lead and mercury levels. Materials & methods: We obtained cervical swabs from pregnant women (n = 60) and quantified cervical miRNA expression. Women's blood lead, bone lead and toenail mercury levels were analyzed. We performed linear regression to examine the association between metal levels and expression of 74 miRNAs adjusting for covariates. Results: Seventeen miRNAs were negatively associated with toenail mercury levels, and tibial bone lead levels were associated with decreased expression of miR-575 and miR-4286. Conclusion: The findings highlight miRNAs in the human cervix as novel responders to maternal chemical exposure during pregnancy. PMID:26418635

  5. Lead bioaccumulation in Opuntia ficus-indica following foliar or root exposure to lead-bearing apatite.

    Science.gov (United States)

    El Hayek, Eliane; El Samrani, Antoine; Lartiges, Bruno; Kazpard, Veronique; Aigouy, Thierry

    2017-01-01

    The contamination of edible leafy vegetables by atmospheric heavy metal-bearing particles is a major issue in environmental toxicology. In this study, the uptake of lead by cladodes of Opuntia ficus-indica (Ofi), traditionally used in Mexican cuisine and in livestock fodder, is investigated after a 4-months exposure of either cladodes or roots to synthetic Pb-fluorapatite particles. Atomic Absorption Spectroscopy (AAS) for the quantitative analysis of Pb levels, Scanning Electron Microscopy coupled with Energy Dispersive X-Ray Spectroscopy (SEM-EDX) for the examination of the cladode surface and fate of particles, and Micro-X-ray fluorescence (μXRF) measurements for elemental mapping of Pb in cladodes, were used. The results evidence that foliar contamination may be a major pathway for the transfer of Pb within Ofi cladodes. The stomata, areoles, and cuticle of cladode surface, play an obvious role in the retention and the incorporation of lead-bearing apatite, thus revealing the hazard of eating contaminated cladodes. The possibility of using series of successive cladodes for biomonitoring the atmospheric pollution in arid and semi-arid regions is also rapidly discussed. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Association of lead and cadmium exposure with frailty in US older adults

    Energy Technology Data Exchange (ETDEWEB)

    García-Esquinas, Esther, E-mail: esthergge@gmail.com [Department of Preventive Medicine and Public Health, School of Medicine, Universidad Autónoma de Madrid/ IdiPAZ, Madrid (Spain); CIBER of Epidemiology and Public Health (CIBERESP), Madrid (Spain); Department of Environmental Health Sciences, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD (United States); Navas-Acien, Ana [Department of Environmental Health Sciences, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD (United States); Department of Epidemiology, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD (United States); Welch Center for Prevention, Epidemiology, and Clinical Research, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD (United States); Pérez-Gómez, Beatriz [CIBER of Epidemiology and Public Health (CIBERESP), Madrid (Spain); Environmental Epidemiology and Cancer Unit, National Center for Epidemiology, Carlos III Institute of Health, Madrid (Spain); Artalejo, Fernando Rodríguez [Department of Preventive Medicine and Public Health, School of Medicine, Universidad Autónoma de Madrid/ IdiPAZ, Madrid (Spain); CIBER of Epidemiology and Public Health (CIBERESP), Madrid (Spain)

    2015-02-15

    Background: Environmental lead and cadmium exposure is associated with higher risk of several age-related chronic diseases, including cardiovascular disease, chronic kidney disease and osteoporosis. These diseases may lead to frailty, a geriatric syndrome characterized by diminished physiologic reserve in multiple systems with decreased ability to cope with acute stressors. However, no previous study has evaluated the association between lead or cadmium exposure and frailty. Methods: Cross-sectional study among individuals aged ≥60 years who participated in the third U.S. National Health and Nutrition Examination Survey and had either blood lead (N=5272) or urine cadmium (N=4887) determinations. Frailty was ascertained with a slight modification of the Fried criteria, so that individuals meeting ≥3 of 5 pre-defined criteria (exhaustion, low body weight, low physical activity, weakness and slow walking speed), were considered as frail. The association between lead and cadmium with frailty was evaluated using logistic regression with adjustment for relevant confounders. Results: Median (intertertile range) concentrations of blood lead and urine cadmium were 3.9 µg/dl (2.9–4.9) and 0.62 µg/l (0.41–0.91), respectively. The prevalence of frailty was 7.1%. The adjusted odds ratios (95% confidence interval) of frailty comparing the second and third to the lowest tertile of blood lead were, respectively, 1.40 (0.96–2.04) and 1.75 (1.33–2.31). Lead concentrations were also associated with the frequency of exhaustion, weakness and slowness. The corresponding odds ratios (95% confidence interval) for cadmium were, respectively, 0.97 (0.68–1.39) and 1.55 (1.03–2.32), but this association did not hold after excluding participants with reduced glomerular filtration rate: 0.70 (0.43–1.14) and 1.09 (0.56–2.11), respectively. Conclusions: In the US older adult population, blood lead but not urine cadmium concentrations showed a direct dose

  7. Association of lead and cadmium exposure with frailty in US older adults

    International Nuclear Information System (INIS)

    García-Esquinas, Esther; Navas-Acien, Ana; Pérez-Gómez, Beatriz; Artalejo, Fernando Rodríguez

    2015-01-01

    Background: Environmental lead and cadmium exposure is associated with higher risk of several age-related chronic diseases, including cardiovascular disease, chronic kidney disease and osteoporosis. These diseases may lead to frailty, a geriatric syndrome characterized by diminished physiologic reserve in multiple systems with decreased ability to cope with acute stressors. However, no previous study has evaluated the association between lead or cadmium exposure and frailty. Methods: Cross-sectional study among individuals aged ≥60 years who participated in the third U.S. National Health and Nutrition Examination Survey and had either blood lead (N=5272) or urine cadmium (N=4887) determinations. Frailty was ascertained with a slight modification of the Fried criteria, so that individuals meeting ≥3 of 5 pre-defined criteria (exhaustion, low body weight, low physical activity, weakness and slow walking speed), were considered as frail. The association between lead and cadmium with frailty was evaluated using logistic regression with adjustment for relevant confounders. Results: Median (intertertile range) concentrations of blood lead and urine cadmium were 3.9 µg/dl (2.9–4.9) and 0.62 µg/l (0.41–0.91), respectively. The prevalence of frailty was 7.1%. The adjusted odds ratios (95% confidence interval) of frailty comparing the second and third to the lowest tertile of blood lead were, respectively, 1.40 (0.96–2.04) and 1.75 (1.33–2.31). Lead concentrations were also associated with the frequency of exhaustion, weakness and slowness. The corresponding odds ratios (95% confidence interval) for cadmium were, respectively, 0.97 (0.68–1.39) and 1.55 (1.03–2.32), but this association did not hold after excluding participants with reduced glomerular filtration rate: 0.70 (0.43–1.14) and 1.09 (0.56–2.11), respectively. Conclusions: In the US older adult population, blood lead but not urine cadmium concentrations showed a direct dose

  8. Dietary exposure to cadmium, lead and nickel among students from south-east Poland.

    Science.gov (United States)

    Marzec, Zbigniew; Koch, Wojciech; Marzec, Agnieszka; Żukiewicz-Sobczak, Wioletta

    2014-01-01

    The dietary intake of cadmium, lead and nickel was determined among students from three universities in the city of Lublin in south-east Poland to assess the levels of exposure to these contaminants, compared to PTWI and TDI values. The study was performed in 2006–2010 and involved 850 daily food rations of students. The technique of 24-hour dietary recall and diet duplicates was used. Cadmium, lead and nickel complexes with ammonium-pyrrolidindithiocarbamate were formed and extracted to the organic phase with 4-methylpentan-2-one–MIBK, in which their content was measured by flame atomic absorption spectrometry. The highest intake of the elements studied was observed in 2008. The data show that in none of the cases, the level of intake reached 70% of PTWI/TDI values, and thus the risk of developing diseases related to high exposure to these toxic metals absorbed from foodstuffs was low. The parameters of methods were checked during determinations by adding standard solutions to the samples before mineralization and by using two reference materials: Total diet ARC/CL HDP and Bovine muscle RM NIST 8414. The dietary exposure to lead and cadmium has significantly decreased in recent years, whereas the exposures to nickel remains on a stable level.

  9. Effects of lead and cadmium exposure from electronic waste on child physical growth.

    Science.gov (United States)

    Yang, Hui; Huo, Xia; Yekeen, Taofeek Akangbe; Zheng, Qiujian; Zheng, Minghao; Xu, Xijin

    2013-07-01

    Many studies indicate that lead (Pb) and cadmium (Cd) exposure may alter bone development through both direct and indirect mechanisms, increasing the risk of osteoporosis later in life. The aim of this study was to investigate the association between Pb and Cd exposure, physical growth, and bone and calcium metabolism in children of an electronic waste (e-waste) processing area. We recruited 246 children (3-8 years) in a kindergarten located in Guiyu, China. Blood lead levels (BLLs) and blood cadmium levels (BCLs) of recruited children were measured as biomarkers for exposure. Serum calcium, osteocalcin, bone alkaline phosphatase, and urinary deoxypyridinoline were used as biomarkers for bone and calcium metabolism. Physical indexes such as height, weight, and head and chest circumference were also measured. The mean values of BLLs and BCLs obtained were 7.30 μg/dL and 0.69 μg/L, respectively. The average of BCLs increased with age. In multiple linear regression analysis, BLLs were negatively correlated with both height and weight, and positively correlated with bone resorption biomarkers. Neither bone nor calcium metabolic biomarkers showed significant correlation with cadmium. Childhood lead exposure affected both physical development and increased bone resorption of children in Guiyu. Primitive e-waste recycling may threaten the health of children with elevated BLL which may eventually cause adult osteoporosis.

  10. Full Cryogenic Test of 600 A HTS Hybrid Current Leads for the LHC

    CERN Document Server

    Al-Mosawi, MK; Beduz, C; Ballarino, A; Yang, Y

    2007-01-01

    For full cryogenic test of CERN 600 A High Temperature Superconducting (HTS) current leads prior to integration into the Large Hadron Collider (LHC), a ded. facility has been designed, constructed and operated at the University of Southampton. The facility consists of purpose-built test cryostats, 20 K helium gas supply, helium gas flow and temperature control systems and quench protection system. Over 400 such leads have already been successfully tested and qualified for installation at CERN. This paper describes various design and operation aspects of the test facility and presents the detailed cryogenic test results of the CERN 600 A current leads, including steady state 20 K flow rates.

  11. Transient characteristics of current lead losses for the large scale high-temperature superconducting rotating machine

    International Nuclear Information System (INIS)

    Le, T. D.; Kim, J. H.; Park, S. I.; Kim, D. J.; Kim, H. M.; Lee, H. G.; Yoon, Y. S.; Jo, Y. S.; Yoon, K. Y.

    2014-01-01

    To minimize most heat loss of current lead for high-temperature superconducting (HTS) rotating machine, the choice of conductor properties and lead geometry - such as length, cross section, and cooling surface area - are one of the various significant factors must be selected. Therefore, an optimal lead for large scale of HTS rotating machine has presented before. Not let up with these trends, this paper continues to improve of diminishing heat loss for HTS part according to different model. It also determines the simplification conditions for an evaluation of the main flux flow loss and eddy current loss transient characteristics during charging and discharging period.

  12. Cognitive disparities, lead plumbing, and water chemistry: prior exposure to water-borne lead and intelligence test scores among World War Two U.S. Army enlistees.

    Science.gov (United States)

    Ferrie, Joseph P; Rolf, Karen; Troesken, Werner

    2012-01-01

    Higher prior exposure to water-borne lead among male World War Two U.S. Army enlistees was associated with lower intelligence test scores. Exposure was proxied by urban residence and the water pH levels of the cities where enlistees lived in 1930. Army General Classification Test scores were six points lower (nearly 1/3 standard deviation) where pH was 6 (so the water lead concentration for a given amount of lead piping was higher) than where pH was 7 (so the concentration was lower). This difference rose with time exposed. At this time, the dangers of exposure to lead in water were not widely known and lead was ubiquitous in water systems, so these results are not likely the effect of individuals selecting into locations with different levels of exposure. Copyright © 2011 Elsevier B.V. All rights reserved.

  13. The effect of the OSHA lead exposure in construction standard on blood lead levels among iron workers employed in bridge rehabilitation.

    Science.gov (United States)

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

    1997-03-01

    Over 50,000 workers are at risk of occupational exposure to lead in the course of renovating the nation's deteriorating infrastructure. In mid-1993, to control exposure to lead in the construction setting OSHA promulgated a Lead in Construction Standard. In this study, we assessed the effect of the mandated changes in exposure conditions which followed the introduction of this new standard. We analyzed changes in baseline and maximum blood lead concentrations and in maximum increments in blood lead levels before and after introduction of the standard among iron workers employed in the renovation of a large, lead-painted, steel bridge in New York City. Results indicated that baseline and maximum blood lead levels fell significantly after the implementation of the provisions of the standard, as did maximum increments in blood lead concentrations. Seventy-six percent of the workers maintained blood lead concentrations below 20 micrograms/dl after the OSHA standard, as compared with 66% prior to its implementation. Increments of 20 micrograms/dl or more occurred considerably more frequently before introduction of the standard (13% before vs. 4% after; p = 0.01). Evidence of decreased exposure to lead was observed among iron workers who were present both before and after the introduction of the OSHA standard, as well as among iron workers newly hired after the OSHA provisions were put in place. These findings document the effectiveness of the OSHA construction lead standard in controlling exposure to lead in this complex and variable environment. The data indicate the utility of blood lead determinations in assessing the outcome of industrial hygiene interventions to reduce exposures to lead in the construction setting.

  14. Human health risk assessment of lead from mining activities at semi-arid locations in the context of total lead exposure.

    Science.gov (United States)

    Zheng, Jiajia; Huynh, Trang; Gasparon, Massimo; Ng, Jack; Noller, Barry

    2013-12-01

    Lead from historical mining and mineral processing activities may pose potential human health risks if materials with high concentrations of bioavailable lead minerals are released to the environment. Since the Joint Expert Committee on Food Additives of Food and Agriculture Organization/World Health Organization withdrew the Provisional Tolerable Weekly Intake of lead in 2011, an alternative method was required for lead exposure assessment. This study evaluated the potential lead hazard to young children (0-7 years) from a historical mining location at a semi-arid area using the U.S. EPA Integrated Exposure Uptake Biokinetic (IEUBK) Model, with selected site-specific input data. This study assessed lead exposure via the inhalation pathway for children living in a location affected by lead mining activities and with specific reference to semi-arid conditions and made comparison with the ingestion pathway by using the physiologically based extraction test for gastro-intestinal simulation. Sensitivity analysis for major IEUBK input parameters was conducted. Three groups of input parameters were classified according to the results of predicted blood concentrations. The modelled lead absorption attributed to the inhalation route was lower than 2 % (mean ± SE, 0.9 % ± 0.1 %) of all lead intake routes and was demonstrated as a less significant exposure pathway to children's blood, compared with ingestion. Whilst dermal exposure was negligible, diet and ingestion of soil and dust were the dominant parameters in terms of children's blood lead prediction. The exposure assessment identified the changing role of dietary intake when house lead loadings varied. Recommendations were also made to conduct comprehensive site-specific human health risk assessment in future studies of lead exposure under a semi-arid climate.

  15. Experimental study of gas-cooled current leads for superconducting magnets

    International Nuclear Information System (INIS)

    Warren, R.P.

    1978-04-01

    Design details and experimental test results from several design variations of the gas-cooled, copper current leads used in conjunction with the superconducting dipole magnets for ESCAR (Experimental Superconducting Accelerator Ring) are reported. Thermal acoustic oscillations, which were experienced with an initial design, were eliminated in subsequent designs by a reduction of the hydraulic diameter. The occurrence of these oscillations is in general agreement with the stability analysis of Rott but the observed gas flow dependence is not in agreement with some other recently reported results for leads operated supercritical phase coolant. An empirically determined correlation was obtained by plotting lead resistance vs. enthalpy gain of the coolant gas. The resulting family of curves can be reduced to a single line on a plot of effective resistivity vs. the product of current and cross-sectional area divided by the product of the square of the mass flow of the coolant and the lead length. This correlation, which should be applicable to other designs of copper current leads in which ideal heat transfer to the coolant gas is approached, predicts that the enthalpy gain of the coolant, and therefore the peak lead temperature, is proportional to the cube of the ratio of current to coolant mass flow. The effective value of the strongly temperature-dependent kinematic viscosity of the coolant gas was found to vary linearly with the effective resistivity of the lead

  16. Mock-up qualification and prototype manufacture for ITER current leads

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Tingzhi, E-mail: tingszhou@ipp.ac.cn [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei (China); Lu, Kun; Ran, Qingxiang; Ding, Kaizhong; Feng, Hansheng; Wu, Huan; Liu, Chenglian; Song, Yuntao [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei (China); Niu, Erwu [CNDA, Ministry of Science and Technology, Beijing (China); Bauer, Pierre; Devred, Arnaud [Magnet Division, ITER Organization, Cadarache (France)

    2015-10-15

    Highlights: • Vacuum brazing and electron beam welding qualification. • Machine and assembly strategy of fin type heat exchanger. • Soldering and joint resistance test of superconducting joint. • Pre-preg technology with vacuum bag on insulation. - Abstract: Three types of high temperature superconducting current leads (HTSCL) are designed to carry 68 kA, 55 kA or 10 kA to the ITER magnets. Before the supply of the HTS current lead series, the design and manufacturing process is qualified through mock-ups and prototypes. Seven mock-ups, representing the critical technologies of the current leads, were built and tested successfully in the Institute of Plasma Physics of the Chinese Academy of Sciences (ASIPP) in 2013. After the qualification some design features of the HTS leads were updated. This paper summarizes the qualification through mock-ups. In 2014 ASIPP started the manufacture of the prototypes. The preparation and manufacturing process are also described.

  17. Health and medical aspects of an accident leading to a radiological exposure

    International Nuclear Information System (INIS)

    2010-02-01

    Ionising radiation damages on health depend on the amount of energy deposited by radiations inside each organ or tissue cells of the human body (irradiation dose). For a given amount of absorbed energy, damages can vary with the type of radiation, the mode of exposure and the affected organ. The effects are of two type: acute and delayed. This paper describes exposure situations leading to both types of effects, the radiation-induced congenital anomalies, and the indirect effects of radiations as well. (J.S.)

  18. Effects of Lead Exposure, Environmental Conditions, and Metapopulation Processes on Population Dynamics of Spectacled Eiders.

    Science.gov (United States)

    Flint, Paul L.; Grand, James B.; Petersen, Margaret; Rockwell, Robert F.

    2016-01-01

    Spectacled eider Somateria fischeri numbers have declined and they are considered threatened in accordance with the US Endangered Species Act throughout their range. We synthesized the available information for spectacled eiders to construct deterministic, stochastic, and metapopulation models for this species that incorporated current estimates of vital rates such as nest success, adult survival, and the impact of lead poisoning on survival. Elasticities of our deterministic models suggested that the populations would respond most dramatically to changes in adult female survival and that the reductions in adult female survival related to lead poisoning were locally important. We also examined the sensitivity of the population to changes in lead exposure rates. With the knowledge that some vital rates vary with environmental conditions, we cast stochastic models that mimicked observed variation in productivity. We also used the stochastic model to examine the probability that a specific population will persist for periods of up to 50 y. Elasticity analysis of these models was consistent with that for the deterministic models, with perturbations to adult female survival having the greatest effect on population projections. When used in single population models, demographic data for some localities predicted rapid declines that were inconsistent with our observations in the field. Thus, we constructed a metapopulation model and examined the predictions for local subpopulations and the metapopulation over a wide range of dispersal rates. Using the metapopulation model, we were able to simulate the observed stability of local subpopulations as well as that of the metapopulation. Finally, we developed a global metapopulation model that simulates periodic winter habitat limitation, similar to that which might be experienced in years of heavy sea ice in the core wintering area of spectacled eiders in the central Bering Sea. Our metapopulation analyses suggested that no

  19. Reconstructing the life-time lead exposure in children using dentine in deciduous teeth

    Energy Technology Data Exchange (ETDEWEB)

    Shepherd, Thomas J., E-mail: shepherdtj@aol.com [School of Earth and Environment, University of Leeds, Leeds LS2 9JT (United Kingdom); Dirks, Wendy [Centre for Oral Health Research, School of Dental Sciences, Newcastle University, Newcastle upon Tyne NE2 4BW (United Kingdom); Manmee, Charuwan; Hodgson, Susan [Institute of Health and Society, Newcastle University, Newcastle upon Tyne NE2 4AX (United Kingdom); Banks, David A. [School of Earth and Environment, University of Leeds, Leeds LS2 9JT (United Kingdom); Averley, Paul [Centre for Oral Health Research, School of Dental Sciences, Newcastle University, Newcastle upon Tyne NE2 4BW (United Kingdom); Queensway Dental Practice, 170 Queensway, Billingham, Teesside TS23 2NT (United Kingdom); Pless-Mulloli, Tanja [Institute of Health and Society, Newcastle University, Newcastle upon Tyne NE2 4AX (United Kingdom); Newcastle Institute for Research on Sustainability, Newcastle University, Newcastle upon Tyne NE1 7RU (United Kingdom)

    2012-05-15

    Data are presented to demonstrate that the circumpulpal dentine of deciduous teeth can be used to reconstruct a detailed record of childhood exposure to lead. By combining high spatial resolution laser ablation ICP-MS with dental histology, information was acquired on the concentration of lead in dentine from in utero to several years after birth, using a true time template of dentine growth. Time corrected lead analyses for pairs of deciduous molars confirmed that between-tooth variation for the same child was negligible and that meaningful exposure histories can be obtained from a single, multi-point ablation transect on longitudinal sections of individual teeth. For a laser beam of 100 {mu}m diameter, the lead signal for each ablation point represented a time span of 42 days. Simultaneous analyses for Sr, Zn and Mg suggest that the incorporation of Pb into dentine (carbonated apatite) is most likely controlled by nanocrystal growth mechanisms. The study also highlights the importance of discriminating between primary and secondary dentine and the dangers of translating lead analyses into blood lead estimates without determining the age or duration of dentine sampled. Further work is in progress to validate deciduous teeth as blood lead biomarkers. - Highlights: Black-Right-Pointing-Pointer Reconstruction of childhood exposure history to Pb using deciduous tooth dentine. Black-Right-Pointing-Pointer Pb analyses acquired for dentine growth increments of 42 days. Black-Right-Pointing-Pointer Highly correlated Pb concentration profiles for pairs of deciduous molars. Black-Right-Pointing-Pointer Data for Sr, Zn and Mg provide a model for the incorporation of Pb into dentine.

  20. Reconstructing the life-time lead exposure in children using dentine in deciduous teeth

    International Nuclear Information System (INIS)

    Shepherd, Thomas J.; Dirks, Wendy; Manmee, Charuwan; Hodgson, Susan; Banks, David A.; Averley, Paul; Pless-Mulloli, Tanja

    2012-01-01

    Data are presented to demonstrate that the circumpulpal dentine of deciduous teeth can be used to reconstruct a detailed record of childhood exposure to lead. By combining high spatial resolution laser ablation ICP-MS with dental histology, information was acquired on the concentration of lead in dentine from in utero to several years after birth, using a true time template of dentine growth. Time corrected lead analyses for pairs of deciduous molars confirmed that between-tooth variation for the same child was negligible and that meaningful exposure histories can be obtained from a single, multi-point ablation transect on longitudinal sections of individual teeth. For a laser beam of 100 μm diameter, the lead signal for each ablation point represented a time span of 42 days. Simultaneous analyses for Sr, Zn and Mg suggest that the incorporation of Pb into dentine (carbonated apatite) is most likely controlled by nanocrystal growth mechanisms. The study also highlights the importance of discriminating between primary and secondary dentine and the dangers of translating lead analyses into blood lead estimates without determining the age or duration of dentine sampled. Further work is in progress to validate deciduous teeth as blood lead biomarkers. - Highlights: ► Reconstruction of childhood exposure history to Pb using deciduous tooth dentine. ► Pb analyses acquired for dentine growth increments of 42 days. ► Highly correlated Pb concentration profiles for pairs of deciduous molars. ► Data for Sr, Zn and Mg provide a model for the incorporation of Pb into dentine.

  1. Family environmental and dietary implications for low-level prenatal lead exposure in Wujiang City, China.

    Science.gov (United States)

    Yan, Jin; Gao, Zhenyan; Wang, Ju; Ma, Wenjuan; Ying, Xiaolan; Zhou, Cancan; Yan, Chonghuai

    2018-05-01

    To explore the potential environmental and dietary factors during pregnancy affecting low-level prenatal lead exposure, we conducted a longitudinal study in Wujiang City, China. A total of 1976 mother-infant pairs were included from 2009 to 2010. An interviewed questionnaire was conducted and cord blood samples were collected. The geometric means of cord blood lead level was 30.3 μg/L (95% CI, 29.8-30.8) with 99.24% below 100 μg/L. Maternal age, passive smoking, and living in the countryside were significantly associated with cord blood lead concentrations. Multiple logistic models showed that some family environmental factors including using firewood and electricity as kitchen fuel were positively correlated with increased cord blood lead levels. Among dietary sources recorded in this study, meat consumption (> 3 times/week), fish consumption (1-3 times/week), vegetables consumption (> 1 times/day), and fruit intake (> 1 times/day) had inverse relationship with cord blood lead levels. In general, our findings may have important implications for family environmental and dietary direction during pregnancy to decrease prenatal lead exposure.

  2. Prenatal exposure to lead in Spain: Cord blood levels and associated factors

    Energy Technology Data Exchange (ETDEWEB)

    Llop, Sabrina, E-mail: llop_sab@gva.es [Centre of Public Health Research (CSISP), Av Catalunya 21, 46020, Valencia (Spain); Carlos III Health Institute (ISCIII), 20220 Majadahonda, Madrid (Spain); CIBER de Epidemiologia y Salud Publica (CIBERESP), Doctor Aiguader 88, 8003 Barcelona (Spain); Aguinagalde, Xabier [Public Health Laboratory of Alava, Direccion de Salud Publica, Gobierno Vasco, Santiago 11, 01002, Vitoria-Gasteiz, Basque Country (Spain); Vioque, Jesus [CIBER de Epidemiologia y Salud Publica (CIBERESP), Doctor Aiguader 88, 8003 Barcelona (Spain); Universidad Miguel Hernandez, Av de Alicante KM 87, 03550, Sant Joan d' Alacant (Spain); Ibarluzea, Jesus [CIBER de Epidemiologia y Salud Publica (CIBERESP), Doctor Aiguader 88, 8003 Barcelona (Spain); Departamento de Sanidad Gobierno Vasco, Subdireccion de Salud Publica de Gipuzkoa, Avenida de Navarra 4, 20013 San Sebastian (Spain); Biodonostia, Instituto de Investigacion Biomedica, San Sebastian (Spain); Guxens, Monica [CIBER de Epidemiologia y Salud Publica (CIBERESP), Doctor Aiguader 88, 8003 Barcelona (Spain); Centre for Research of Environmental Epidemiology (CREAL), Doctor Aiguader 88, 8003 Barcelona (Spain); Municipal Institute of Medical Research (IMIM-Hospital del Mar), Doctor Aiguader 88, 8003 Barcelona (Spain); Casas, Maribel [Centre for Research of Environmental Epidemiology (CREAL), Doctor Aiguader 88, 8003 Barcelona (Spain); Municipal Institute of Medical Research (IMIM-Hospital del Mar), Doctor Aiguader 88, 8003 Barcelona (Spain); Murcia, Mario [Centre of Public Health Research (CSISP), Av Catalunya 21, 46020, Valencia (Spain); CIBER de Epidemiologia y Salud Publica (CIBERESP), Doctor Aiguader 88, 8003 Barcelona (Spain); Ruiz, Maria [Centre for Research of Environmental Epidemiology (CREAL), Doctor Aiguader 88, 8003 Barcelona (Spain); Municipal Institute of Medical Research (IMIM-Hospital del Mar), Doctor Aiguader 88, 8003 Barcelona (Spain); and others

    2011-05-01

    Introduction and Objective: 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). Methods: 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 < 2 {mu}g/dL). Results: A low percentage of cord blood samples with lead levels {>=} 2 {mu}g/dL were found (5.9%). Geometric mean and maximum were 1.06 {mu}g/dL and 19 {mu}g/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 {>=} 2 {mu}g/dL. Conclusion: 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. - Research Highlights: {yields} Pb is a ubiquitous environmental pollutant with harmful effects on neurodevelopment. {yields} Cord blood Pb levels in

  3. Prenatal exposure to lead in Spain: Cord blood levels and associated factors

    International Nuclear Information System (INIS)

    Llop, Sabrina; Aguinagalde, Xabier; Vioque, Jesus; Ibarluzea, Jesus; Guxens, Monica; Casas, Maribel; Murcia, Mario; Ruiz, Maria

    2011-01-01

    Introduction and Objective: 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). Methods: 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 < 2 μg/dL). Results: A low percentage of cord blood samples with lead levels ≥ 2 μg/dL were found (5.9%). Geometric mean and maximum were 1.06 μg/dL and 19 μg/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 ≥ 2 μg/dL. Conclusion: 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. - Research Highlights: → Pb is a ubiquitous environmental pollutant with harmful effects on neurodevelopment. → Cord blood Pb levels in Spanish newborn are low in

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

    Science.gov (United States)

    Fernandez, Julia Rodriguez-Ramos; Hofle, Ursula; Mateo, Rafael; de Francisco, Olga Nicolas; Abbott, Rachel; Acevedo, Pelayo; Blanco, Juan-Manuel

    2011-01-01

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

  5. Qualification of Fin-Type Heat Exchangers for the ITER Current Leads

    CERN Document Server

    Ballarino, A; Bordini, B; Devred, A; Ding, K; Niu, E; Sitko, M; Taylor, T; Yang, Y; Zhou, T

    2015-01-01

    The ITER current leads will transfer large currents of up to 68 kA into the biggest superconducting magnets ever built. Following the development of prototypes and targeted trials of specific manufacturing processes through mock-ups, the ASIPP (Chinese Institute of Plasma Physics) is preparing for the series fabrication. A key component of the ITER HTS current leads are the resistive heat exchangers. Special R&D was conducted for these components at CERN and ASIPP in support of their designs. In particular several mock-ups were built and tested in room temperature gas to measure the dynamic pressure drop and compare to 3D CFD models.

  6. Research and development of an aimed magnetic lead current density-magnetic field diagnostic. Final report

    International Nuclear Information System (INIS)

    1985-01-01

    A diagnostics survey was made to provide a clear definition of advanced diagnostic needs and the limitations of current approaches in addressing those needs. Special attention was given to the adequacy with which current diagnostics are interfaced to signal processing/data acquisition devices and systems. Critical evaluations of selected alternative diagnostic techniques for future R and D activities are presented. The conceptual basis of the Aimed Magnetic Lead Gradiometric system as a current density/magnetic field diagnostic is established

  7. [Effects of lead exposure on the human body and health implications].

    Science.gov (United States)

    Moreira, Fátima Ramos; Moreira, Josino Costa

    2004-02-01

    To review the literature concerning the risks associated with exposure to lead and lead compounds, especially in children and in populations that are occupationally exposed. Using "chumbo" [lead] and "efeitos" [effects] as search terms, two large databases, namely PubMed (United States National Library of Medicine) and LILACS (Literatura Latino-Americana e do Caribe em Ciências da Saúde [Latin American and Caribbean Literature in the Health Sciences]), were searched for studies on lead toxicity from 1988 to 2002. Other sources used to conduct the search include the web page of the United States Agency for Toxic Substances and Disease Registry, in Atlanta, Georgia, and the library of the Toxicology Laboratory of the Center for Workers' Health and Human Ecology at the National School of Public Health [Centro de Estudos da Saúde de Trabalhador e Ecologia Humana, Escola Nacional de Saúde Pública], Fundação Oswaldo Cruz, Rio de Janeiro, Brazil. The toxic effects of lead and lead compounds have been extensively studied for over a century. In recent years, epidemiologic studies have focused primarily on the neurotoxic effects of lead on children, particularly in terms of impaired intellectual ability and behavioral problems. However, there is still insufficient information on the mechanisms of action that account for such toxicity. More in-depth studies are also needed on the effects of lead exposure on bone, the central nervous system, the cardiovascular system, the kidneys, the liver, the male and female reproductive systems, and the endocrine system. The potential teratogenicity and carcinogenicity of lead, as well as its effect on pregnancy outcomes and neonatal growth and development, also require further study.

  8. Burden of higher lead exposure in African-Americans starts in utero and persists into childhood.

    Science.gov (United States)

    Cassidy-Bushrow, Andrea E; Sitarik, Alexandra R; Havstad, Suzanne; Park, Sung Kyun; Bielak, Lawrence F; Austin, Christine; Johnson, Christine Cole; Arora, Manish

    2017-11-01

    Recent public health lead crises in urban areas emphasize the need to better understand exposure to environmental toxicants, particularly in higher risk groups. Although African-American children have the highest prevalence of elevated blood lead levels in the United States, little is known about when this trajectory of disproportionate burden of lead exposure first emerges. Using tooth-matrix biomarkers that directly measure fetal and early childhood metal levels, the primary goal of this study was to determine if there were racial disparities in lead levels during fetal development and early childhood. Manganese, an essential nutrient that modifies the neurotoxic effects of lead, was also measured. Pregnant women served by the Henry Ford Health System and living in a predefined geographic area in and around Detroit, Michigan, were recruited during the second trimester or later into the Wayne County Health, Environment, Allergy and Asthma Longitudinal Study (WHEALS), a population-based birth cohort. Offspring born between September 2003 and December 2007 were studied in childhood. Child race was parent-reported. Lead and manganese during the second and third trimesters, early postnatal life (birth through age 1year) and early childhood (age 1 through time of tooth shedding, which ranges from 6 to 12years) were measured via high-resolution microspatial mapping of dentin growth rings, a validated biomarker for prenatal and childhood metal exposure. African-American children (N=71) had 2.2 times higher lead levels in the second and third trimesters (both pAfrican-American children were also higher during childhood, but this effect was only marginally significant (p=0.066) and was attenuated after covariate adjustment. Additionally, we observed that African-American children had lower tooth‑manganese levels during the third trimester (p=0.063) and postnatally (p=0.043), however these differences were attenuated after covariate adjustment. The disproportionate burden

  9. Soil intervention as a strategy for lead exposure prevention: The New Orleans lead-safe childcare playground project

    Energy Technology Data Exchange (ETDEWEB)

    Mielke, Howard W., E-mail: howard.mielke@gmail.com [Department of Chemistry, Tulane University, New Orleans, LA 70118 (United States); Center for Bioenvironmental Research at Tulane and Xavier Universities, 1430 Tulane Avenue SL-3, New Orleans, LA 70112 (United States); Covington, Tina P. [Charity School of Nursing, Delgado Community College, New Orleans, LA 70112-1397 (United States); College of Nursing, University of South Alabama, Doctor of Nursing Practice Program (student), Mobile AL 36688-0002 (United States); Mielke, Paul W. [Department of Statistics, Colorado State University, Fort Collins, CO 80523-1877 (United States); Wolman, Fredericka J. [Director of Pediatrics, Department of Children and Families, State of Connecticut, Hartford, CT 06473 (United States); Powell, Eric T.; Gonzales, Chris R. [Lead Lab, Inc., New Orleans, LA 70179-1125 (United States)

    2011-08-15

    The feasibility of reducing children's exposure to lead (Pb) polluted soil in New Orleans is tested. Childcare centers (median = 48 children) are often located in former residences. The extent of soil Pb was determined by selecting centers in both the core and outlying areas. The initial 558 mg/kg median soil Pb (range 14-3692 mg/kg) decreased to median 4.1 mg/kg (range 2.2-26.1 mg/kg) after intervention with geotextile covered by 15 cm of river alluvium. Pb loading decreased from a median of 4887 {mu}g/m{sup 2} (454 {mu}g/ft{sup 2}) range 603-56650 {mu}g/m{sup 2} (56-5263 {mu}g/ft{sup 2}) to a median of 398 {mu}g/m{sup 2} (37 {mu}g/ft{sup 2}) range 86-980 {mu}g/m{sup 2} (8-91 {mu}g/ft{sup 2}). Multi-Response Permutation Procedures indicate similar (P-values = 0.160-0.231) soil Pb at childcare centers compared to soil Pb of nearby residential communities. At {approx}$100 per child, soil Pb and surface loading were reduced within hours, advancing an upstream intervention conceptualization about Pb exposure prevention. - Highlights: > Upstream thinking refers to attending to causative agents that affect outcomes. > New Orleans has a high density soil Pb map of all residential communities. > Many childcare centers are located in Pb polluted residential communities. > Evaluation of childcare center playground soils substantiated severe Pb pollution. > Pursuing upstream thinking, low Pb soil was put on playgrounds to protect children. - Within hours, at a cost of about U.S. $100 (2010) per child, it is feasible to transform exterior play areas at childcare centers from Pb contaminated to Pb-safe with a large margin of safety.

  10. Lead bullet fragments in venison from rifle-killed deer: potential for human dietary exposure.

    Directory of Open Access Journals (Sweden)

    W Grainger Hunt

    Full Text Available Human consumers of wildlife killed with lead ammunition may be exposed to health risks associated with lead ingestion. This hypothesis is based on published studies showing elevated blood lead concentrations in subsistence hunter populations, retention of ammunition residues in the tissues of hunter-killed animals, and systemic, cognitive, and behavioral disorders associated with human lead body burdens once considered safe. Our objective was to determine the incidence and bioavailability of lead bullet fragments in hunter-killed venison, a widely-eaten food among hunters and their families. We radiographed 30 eviscerated carcasses of White-tailed Deer (Odocoileus virginianus shot by hunters with standard lead-core, copper-jacketed bullets under normal hunting conditions. All carcasses showed metal fragments (geometric mean = 136 fragments, range = 15-409 and widespread fragment dispersion. We took each carcass to a separate meat processor and fluoroscopically scanned the resulting meat packages; fluoroscopy revealed metal fragments in the ground meat packages of 24 (80% of the 30 deer; 32% of 234 ground meat packages contained at least one fragment. Fragments were identified as lead by ICP in 93% of 27 samples. Isotope ratios of lead in meat matched the ratios of bullets, and differed from background lead in bone. We fed fragment-containing venison to four pigs to test bioavailability; four controls received venison without fragments from the same deer. Mean blood lead concentrations in pigs peaked at 2.29 microg/dL (maximum 3.8 microg/dL 2 days following ingestion of fragment-containing venison, significantly higher than the 0.63 microg/dL averaged by controls. We conclude that people risk exposure to bioavailable lead from bullet fragments when they eat venison from deer killed with standard lead-based rifle bullets and processed under normal procedures. At risk in the U.S. are some ten million hunters, their families, and low

  11. Drift in ocean currents impacts intergenerational microbial exposure to temperature

    NARCIS (Netherlands)

    Doblin, Martina A.; Van Sebille, Erik

    2016-01-01

    Microbes are the foundation of marine ecosystems [Falkowski PG, Fenchel T, Delong EF (2008) Science 320(5879):1034-1039]. Until now, the analytical framework for understanding the implications of ocean warming on microbes has not considered thermal exposure during transport in dynamic seascapes,

  12. Conceptual design of cooling anchor for current lead on HTS field coils

    Energy Technology Data Exchange (ETDEWEB)

    Hyeon, C. J.; Kim, J. H.; Quach, H. L. [Dept. of Electrical Engineering, Jeju National University, Jeju (Korea, Republic of); and others

    2017-06-15

    The role of current lead in high-temperature superconducting synchronous machine (HTSSM) is to function as a power supply by connecting the power supply unit at room temperature with the HTS field coils at cryogenic temperature. Such physical and electrical connection causes conduction and Joule-heating losses, which are major thermal losses of HTSSM rotors. To ensure definite stability and economic feasibility of HTS field coils, quickly and smoothly cooling down the current lead is a key design technology. Therefore, in this paper, we introduce a novel concept of a cooling anchor to enhance the cooling performance of a metal current lead. The technical concept of this technology is the simultaneously chilling and supporting the current lead. First, the structure of the current lead and cooling anchor were conceptually designed for field coils for a 1.5 MW-class HTSSM. Then, the effect of this installation on the thermal characteristics of HTS coils was investigated by 3D finite element analysis.

  13. Lifetime exposure to low doses of lead in rats: effect on selected parameters of carbohydrate metabolism.

    Science.gov (United States)

    Nováková, Jaroslava; Lukačínová, Agnesa; Lovásová, Eva; Cimboláková, Iveta; Rácz, Oliver; Ništiar, František

    2015-05-01

    The aim of the study was to assess the effects of exposure to low doses of lead dissolved in drinking water (average daily dose of 2.2 mg kg(-1) day(-1)) on selected carbohydrate metabolism parameters in 20 wistar rats. Animals were divided into two groups - control (C) (group drinking clear water) and experimental group (Pb; group exposed to low doses of lead acetate in a concentration of 100 μmol l(-1) of drinking water). In this study, we studied the biochemical parameters (glucose, haemoglobin (Hb), glycated haemoglobin (HbA1c), lactate dehydrogenase (LDH) and amylase (AMS)) in rat blood. Glucose and Hb concentration and AMS activity decreased, LDH activity increased but HbA1c concentration levels did not change in rats exposed to lead. Our results well documented that lifetime exposure to lead affected carbohydrate metabolism of rats. Some parameters like concentration of Hb as well as activities of AMS and LDH are useful markers of intoxication of rats with lead. For the evaluation of results (e.g. AMS), not only the data at the end of the experiment should be taken into account but also the entire duration of trials (i.e. more time steps) that makes results more objective should be considered. © The Author(s) 2013.

  14. Low-level lead exposure and autistic behaviors in school-age children.

    Science.gov (United States)

    Kim, Kyoung-Nam; Kwon, Ho-Jang; Hong, Yun-Chul

    2016-03-01

    The association between lead exposure and autism spectrum disorder is inconclusive. We hypothesized an association between higher blood lead concentrations and more autistic behaviors, including impaired social interactions and communication, stereotypical behaviors, and restricted interests, among school-age children. Data from 2473 Korean children aged 7-8years who had no prior history of developmental disorders were analyzed. Two follow-up surveys were conducted biennially until the children reached 11-12years of age. Blood lead concentrations were measured at every survey, and autistic behaviors were evaluated at 11-12years of age using the Autism Spectrum Screening Questionnaire (ASSQ) and Social Responsiveness Scale (SRS). The associations of blood lead concentration with ASSQ and SRS scores were analyzed using negative binomial, logistic, and linear regression models. Blood lead concentrations at 7-8years of age (geometric mean: 1.64μg/dL), but not at 9-10 and 11-12years of age, were associated with more autistic behaviors at 11-12years of age, according to the ASSQ (β=0.151; 95% confidence interval [CI]: 0.061, 0.242) and SRS (β=2.489; 95% CI: 1.378, 3.600). SRS subscale analysis also revealed associations between blood lead concentrations and social awareness, cognition, communication, motivation, and mannerisms. Even low blood lead concentrations at 7-8years of age are associated with more autistic behaviors at 11-12years of age, underscoring the need for continued efforts to reduce lead exposure. Copyright © 2016. Published by Elsevier B.V.

  15. Acute exposure to lead increases myocardial contractility independent of hypertension development

    Energy Technology Data Exchange (ETDEWEB)

    Fioresi, M. [Programa de Pós-Graduação em Ciências Fisiológicas, Centro de Ciências da Saúde, Universidade Federal do Espírito Santo, Vitória, ES (Brazil); Departamento de Enfermagem, Centro de Ciências da Saúde, Universidade Federal do Espírito Santo, Vitória, ES (Brazil); Furieri, L.B.; Simões, M.R.; Ribeiro, R.F. Junior; Meira, E.F.; Fernandes, A.A.; Stefanon, I. [Programa de Pós-Graduação em Ciências Fisiológicas, Centro de Ciências da Saúde, Universidade Federal do Espírito Santo, Vitória, ES (Brazil); Vassallo, D.V. [Programa de Pós-Graduação em Ciências Fisiológicas, Centro de Ciências da Saúde, Universidade Federal do Espírito Santo, Vitória, ES (Brazil); Centro de Ciências da Saúde de Vitória, Escola Superior de Ciências da Santa Casa de Misericórdia de Vitória, Vitória, ES (Brazil)

    2013-02-01

    We studied the effects of the acute administration of small doses of lead over time on hemodynamic parameters in anesthetized rats to determine if myocardial contractility changes are dependent or not on the development of hypertension. Male Wistar rats received 320 µg/kg lead acetate iv once, and their hemodynamic parameters were measured for 2 h. Cardiac contractility was evaluated in vitro using left ventricular papillary muscles as were Na{sup +},K{sup +}-ATPase and myosin Ca{sup 2+}-ATPase activities. Lead increased left- (control: 112 ± 3.7 vs lead: 129 ± 3.2 mmHg) and right-ventricular systolic pressures (control: 28 ± 1.2 vs lead: 34 ± 1.2 mmHg) significantly without modifying heart rate. Papillary muscles were exposed to 8 µM lead acetate and evaluated 60 min later. Isometric contractions increased (control: 0.546 ± 0.07 vs lead: 0.608 ± 0.06 g/mg) and time to peak tension decreased (control: 268 ± 13 vs lead: 227 ± 5.58 ms), but relaxation time was unchanged. Post-pause potentiation was similar between groups (n = 6 per group), suggesting no change in sarcoplasmic reticulum activity, evaluated indirectly by this protocol. After 1-h exposure to lead acetate, the papillary muscles became hyperactive in response to a β-adrenergic agonist (10 µM isoproterenol). In addition, post-rest contractions decreased, suggesting a reduction in sarcolemmal calcium influx. The heart samples treated with 8 µM lead acetate presented increased Na{sup +},K{sup +}-ATPase (approximately 140%, P < 0.05 for control vs lead) and myosin ATPase (approximately 30%, P < 0.05 for control vs lead) activity. Our results indicated that acute exposure to low lead concentrations produces direct positive inotropic and lusitropic effects on myocardial contractility and increases the right and left ventricular systolic pressure, thus potentially contributing to the early development of hypertension.

  16. Towards a 20 kA high temperature superconductor current lead module using REBCO tapes

    Science.gov (United States)

    Heller, R.; Bagrets, N.; Fietz, W. H.; Gröner, F.; Kienzler, A.; Lange, C.; Wolf, M. J.

    2018-01-01

    Most of the large fusion devices presently under construction or in operation consisting of superconducting magnets like EAST, Wendelstein 7-X (W7-X), JT-60SA, and ITER, use high temperature superconductor (HTS) current leads (CL) to reduce the cryogenic load and operational cost. In all cases, the 1st generation HTS material Bi-2223 is used which is embedded in a low-conductivity matrix of AgAu. In the meantime, industry worldwide concentrates on the production of the 2nd generation HTS REBCO material because of the better field performance in particular at higher temperature. As the new material can only be produced in a multilayer thin-film structure rather than as a multi-filamentary tape, the technology developed for Bi-2223-based current leads cannot be transferred directly to REBCO. Therefore, several laboratories are presently investigating the design of high current HTS current leads made of REBCO. Karlsruhe Institute of Technology is developing a 20 kA HTS current lead using brass-stabilized REBCO tapes—as a further development to the Bi-2223 design used in the JT-60SA current leads. The same copper heat exchanger module as in the 20 kA JT-60SA current lead will be used for simplicity, which will allow a comparison of the newly developed REBCO CL with the earlier produced and investigated CL for JT-60SA. The present paper discusses the design and accompanying test of single tape and stack REBCO mock-ups. Finally, the fabrication of the HTS module using REBCO stacks is described.

  17. Effect of low lead exposure on gestational age, birth weight and premature rupture of the membrane

    International Nuclear Information System (INIS)

    Mirghani, Z.

    2010-01-01

    Objective: To find out the effect of prenatal exposure to low lead from cosmetics on gestational age, premature rupture of the membrane and birth weight. Methods: The study was carried out in the mountainous Aseer region, Southwest of Saudi Arabia where the air is thought to be clean and free of lead pollution due to the absence of petroleum smelting and other heavy industries. The region is famous as a holiday resort for tourists from Arabia and the gulf countries. All 176 pregnant women included in the study were of singleton pregnancies of gestational age 27 weeks or more who attended the antenatal outpatient clinic of the main maternity hospital. On the day of delivery 4 milliliters of venous blood from each singleton parturient was placed in a heparinized non-silica containing tube and stored at -20 deg. C prior to analysis. Results: Ninety-four (70.1%) women out of 134 had maternal blood lead concentration 200 mu g/L. The mean difference in gestational age was 10.5 days, showing a non significant difference (P=0.152). Ninety-three women (72.7%) out of a total of 128 who had blood lead concentration 200 mu g/L gave birth to infants weighing an average of 2.99 kg. The mean difference was 0.12 kg which is non-significant (P=0.261). Regarding premature rupture of the membrane a total of 127 women with maternal blood lead levels above 200 mu g/L showed no significant differences (P=0.64). The Chi-square test of the relationship between the birth weight (kg) and the levels of blood lead below 150 mu g/L was not significant while the relationship between the birth weight (kg) and the levels of blood lead above 200 mu g/L resulted in very slight differences in the values of infants' birth weight. Conclusion: The detected low lead exposures from cosmetics does not produce statistically significant effects on the three pregnancy outcomes; gestational age, premature rupture of the membrane or birth weight. However, the importance of low lead exposure from the 100% lead

  18. Effect of low lead exposure on gestational age, birth weight and premature rupture of the membrane.

    Science.gov (United States)

    Mirghani, Zein

    2010-12-01

    To find out the effect of prenatal exposure to low lead from cosmetics on gestational age, premature rupture of the membrane and birth weight. The study was carried out in the mountainous Aseer region, Southwest of Saudi Arabia where the air is thought to be clean and free of lead pollution due to the absence of petroleum smelting and other heavy industries. The region is famous as a holiday resort for tourists from Arabia and the gulf countries. All 176 pregnant women included in the study were of singleton pregnancies of gestational age 27 weeks or more who attended the antenatal outpatient clinic of the main maternity hospital. On the day of delivery 4 milliliters of venous blood from each singleton parturient was placed in a heparinized non-silica containing tube and stored at -20 degrees C prior to analysis. Ninety-four (70.1%) women out of 134 had maternal blood lead concentration 200 microg/L. The mean difference in gestational age was 10.5 days, showing a non significant difference (P=0.152). Ninety-three women (72.7%) out of a total of 128 who had blood lead concentration 200 microg/L gave birth to infants weighing an average of 2.99 kg. The mean difference was 0.12 kg which is non-significant (P=0.261). Regarding premature.rupture of the membrane a total of 127 women with maternal blood lead levels above 200 microg/L showed no significant differences (P=0.64). The Chi-square test of the relationship between the birth weight (kg) and the levels of blood lead below 150 microg/L was not significant while the relationship between the birth weight (kg) and the levels of blood lead above 200 microg/L resulted in very slight differences in the values of infants' birth weight. The detected low lead exposures from cosmetics does not produce statistically significant effects on the three pregnancy outcomes; gestational age, premature rupture of the membrane or birth weight. However, the importance of low lead exposure from the 100% lead sulfide eye cosmetic "kohl

  19. A comparison of the diminution rates of lead in blood and lead mobilized by CaEDTA after termination of occupational exposure: a long-term observation in two lead workers.

    Science.gov (United States)

    Araki, S; Murata, K; Aono, H; Yanagihara, S; Ushio, K

    1983-07-01

    CaEDTA 20 mg/kg was administered weekly for 3.5 years after termination of occupational exposure to two lead workers. The diminution half-lives for lead in blood and urine lead mobilized by CaEDTA were 4.8 and 3.3 years respectively for subject 1 following 28 years exposure and 3.3 and 2.0 years respectively for subject 2 following 26 years exposure. The difference in the diminution rate between lead in blood and lead mobilized by CaEDTA was significant in subject 2 (p less than 0.05).

  20. Tracing fetal and childhood exposure to lead using isotope analysis of deciduous teeth

    International Nuclear Information System (INIS)

    Shepherd, Thomas J.; Dirks, Wendy; Roberts, Nick M.W.; Patel, Jaiminkumar G.; Hodgson, Susan; Pless-Mulloli, Tanja; Walton, Pamela; Parrish, Randall R.

    2016-01-01

    We report progress in using the isotopic composition and concentration of Pb in the dentine and enamel of deciduous teeth to provide a high resolution time frame of exposure to Pb during fetal development and early childhood. Isotope measurements (total Pb and 208 Pb/ 206 Pb, 207 Pb/ 206 Pb ratios) were acquired by laser ablation inductively coupled mass spectrometry at contiguous 100 micron intervals across thin sections of the teeth; from the outer enamel surface to the pulp cavity. Teeth samples (n=10) were selected from two cohorts of children, aged 5–8 years, living in NE England. By integrating the isotope data with histological analysis of the teeth, using the daily incremental lines in dentine, we were able to assign true estimated ages to each ablation point (first 2–3 years for molars, first 1–2 years for incisors+pre-natal growth). Significant differences were observed in the isotope composition and concentration of Pb between children, reflecting differences in the timing and sources of exposure during early childhood. Those born in 2000, after the withdrawal of leaded petrol in 1999, have the lowest dentine Pb levels (<0.2 µg Pb/g) with 208 Pb/ 206 Pb (mean ±2σ: 2.126–2.079) 208 Pb/ 206 Pb (mean ±2σ: 0.879–0.856) ratios that correlate very closely with modern day Western European industrial aerosols (PM 10 , PM 2.5 ) suggesting that diffuse airborne pollution was probably the primary source and exposure pathway. Legacy lead, if present, is insignificant. For those born in 1997, dentine lead levels are typically higher (>0.4 µgPb/g) with 208 Pb/ 206 Pb (mean ±2σ: 2.145–2.117) 208 Pb/ 206 Pb (mean ±2σ: 0.898–0.882) ratios that can be modelled as a binary mix between industrial aerosols and leaded petrol emissions. Short duration, high intensity exposure events (1–2 months) were readily identified, together with evidence that dentine provides a good proxy for childhood changes in the isotope composition of blood Pb. Our pilot

  1. Tracing fetal and childhood exposure to lead using isotope analysis of deciduous teeth

    Energy Technology Data Exchange (ETDEWEB)

    Shepherd, Thomas J. [Centre for Oral Health Research, School of Dental Sciences, Newcastle University, Newcastle upon Tyne (United Kingdom); British Geological Survey, Keyworth, Nottingham (United Kingdom); Dirks, Wendy [Department of Anthropology, Durham University, Durham (United Kingdom); Roberts, Nick M.W. [NERC Isotope Geosciences Laboratory, British Geological Survey, Nottingham (United Kingdom); Patel, Jaiminkumar G. [Leeds Dental Institute, University Leeds, Leeds (United Kingdom); Hodgson, Susan [MRC-PHE Centre for Environment and Health, Department of Epidemiology and Biostatistics, Imperial College London (United Kingdom); Pless-Mulloli, Tanja [Institute of Health and Society, Newcastle University, Newcastle upon Tyne (United Kingdom); Walton, Pamela [Centre for Oral Health Research, School of Dental Sciences, Newcastle University, Newcastle upon Tyne (United Kingdom); Parrish, Randall R. [British Geological Survey, Keyworth, Nottingham (United Kingdom)

    2016-04-15

    We report progress in using the isotopic composition and concentration of Pb in the dentine and enamel of deciduous teeth to provide a high resolution time frame of exposure to Pb during fetal development and early childhood. Isotope measurements (total Pb and {sup 208}Pb/{sup 206}Pb, {sup 207}Pb/{sup 206}Pb ratios) were acquired by laser ablation inductively coupled mass spectrometry at contiguous 100 micron intervals across thin sections of the teeth; from the outer enamel surface to the pulp cavity. Teeth samples (n=10) were selected from two cohorts of children, aged 5–8 years, living in NE England. By integrating the isotope data with histological analysis of the teeth, using the daily incremental lines in dentine, we were able to assign true estimated ages to each ablation point (first 2–3 years for molars, first 1–2 years for incisors+pre-natal growth). Significant differences were observed in the isotope composition and concentration of Pb between children, reflecting differences in the timing and sources of exposure during early childhood. Those born in 2000, after the withdrawal of leaded petrol in 1999, have the lowest dentine Pb levels (<0.2 µg Pb/g) with {sup 208}Pb/{sup 206}Pb (mean ±2σ: 2.126–2.079) {sup 208}Pb/{sup 206}Pb (mean ±2σ: 0.879–0.856) ratios that correlate very closely with modern day Western European industrial aerosols (PM{sub 10}, PM{sub 2.5}) suggesting that diffuse airborne pollution was probably the primary source and exposure pathway. Legacy lead, if present, is insignificant. For those born in 1997, dentine lead levels are typically higher (>0.4 µgPb/g) with {sup 208}Pb/{sup 206}Pb (mean ±2σ: 2.145–2.117) {sup 208}Pb/{sup 206}Pb (mean ±2σ: 0.898–0.882) ratios that can be modelled as a binary mix between industrial aerosols and leaded petrol emissions. Short duration, high intensity exposure events (1–2 months) were readily identified, together with evidence that dentine provides a good proxy for childhood

  2. Gestational lead exposure selectively decreases retinal dopamine amacrine cells and dopamine content in adult mice

    Energy Technology Data Exchange (ETDEWEB)

    Fox, Donald A., E-mail: dafox@uh.edu [College of Optometry, University of Houston, Houston, TX (United States); Department of Biology and Biochemistry, University of Houston, Houston, TX (United States); Department of Pharmacology and Pharmaceutical Sciences, University of Houston, Houston, TX (United States); Hamilton, W. Ryan [Department of Biology and Biochemistry, University of Houston, Houston, TX (United States); Johnson, Jerry E. [Department of Natural Sciences, University of Houston-Downtown, Houston, TX (United States); Xiao, Weimin [College of Optometry, University of Houston, Houston, TX (United States); Chaney, Shawntay; Mukherjee, Shradha [Department of Biology and Biochemistry, University of Houston, Houston, TX (United States); Miller, Diane B.; O' Callaghan, James P. [Toxicology and Molecular Biology Branch, Health Effects Research Laboratory, Centers for Disease Control and Prevention-NIOSH, Morgantown, WV USA (United States)

    2011-11-15

    Gestational lead exposure (GLE) produces supernormal scotopic electroretinograms (ERG) in children, monkeys and rats, and a novel retinal phenotype characterized by an increased number of rod photoreceptors and bipolar cells in adult mice and rats. Since the loss of dopaminergic amacrine cells (DA ACs) in GLE monkeys and rats contributes to supernormal ERGs, the retinal DA system was analyzed in mice following GLE. C57BL/6 female mice were exposed to low (27 ppm), moderate (55 ppm) or high (109 ppm) lead throughout gestation and until postnatal day 10 (PN10). Blood [Pb] in control, low-, moderate- and high-dose GLE was {<=} 1, {<=} 10, {approx} 25 and {approx} 40 {mu}g/dL, respectively, on PN10 and by PN30 all were {<=} 1 {mu}g/dL. At PN60, confocal-stereology studies used vertical sections and wholemounts to characterize tyrosine hydroxylase (TH) expression and the number of DA and other ACs. GLE dose-dependently and selectively decreased the number of TH-immunoreactive (IR) DA ACs and their synaptic plexus without affecting GABAergic, glycinergic or cholinergic ACs. Immunoblots and confocal revealed dose-dependent decreases in retinal TH protein expression and content, although monoamine oxidase-A protein and gene expression were unchanged. High-pressure liquid chromatography showed that GLE dose-dependently decreased retinal DA content, its metabolites and DA utilization/release. The mechanism of DA selective vulnerability is unknown. However, a GLE-induced loss/dysfunction of DA ACs during development could increase the number of rods and bipolar cells since DA helps regulate neuronal proliferation, whereas during adulthood it could produce ERG supernormality as well as altered circadian rhythms, dark/light adaptation and spatial contrast sensitivity. -- Highlights: Black-Right-Pointing-Pointer Peak [BPb] in control, low-, moderate- and high-dose newborn mice with gestational lead exposure: {<=} 1, {<=} 10, 25 and 40 {mu}g/dL Black

  3. Gestational lead exposure selectively decreases retinal dopamine amacrine cells and dopamine content in adult mice

    International Nuclear Information System (INIS)

    Fox, Donald A.; Hamilton, W. Ryan; Johnson, Jerry E.; Xiao, Weimin; Chaney, Shawntay; Mukherjee, Shradha; Miller, Diane B.; O'Callaghan, James P.

    2011-01-01

    Gestational lead exposure (GLE) produces supernormal scotopic electroretinograms (ERG) in children, monkeys and rats, and a novel retinal phenotype characterized by an increased number of rod photoreceptors and bipolar cells in adult mice and rats. Since the loss of dopaminergic amacrine cells (DA ACs) in GLE monkeys and rats contributes to supernormal ERGs, the retinal DA system was analyzed in mice following GLE. C57BL/6 female mice were exposed to low (27 ppm), moderate (55 ppm) or high (109 ppm) lead throughout gestation and until postnatal day 10 (PN10). Blood [Pb] in control, low-, moderate- and high-dose GLE was ≤ 1, ≤ 10, ∼ 25 and ∼ 40 μg/dL, respectively, on PN10 and by PN30 all were ≤ 1 μg/dL. At PN60, confocal-stereology studies used vertical sections and wholemounts to characterize tyrosine hydroxylase (TH) expression and the number of DA and other ACs. GLE dose-dependently and selectively decreased the number of TH-immunoreactive (IR) DA ACs and their synaptic plexus without affecting GABAergic, glycinergic or cholinergic ACs. Immunoblots and confocal revealed dose-dependent decreases in retinal TH protein expression and content, although monoamine oxidase-A protein and gene expression were unchanged. High-pressure liquid chromatography showed that GLE dose-dependently decreased retinal DA content, its metabolites and DA utilization/release. The mechanism of DA selective vulnerability is unknown. However, a GLE-induced loss/dysfunction of DA ACs during development could increase the number of rods and bipolar cells since DA helps regulate neuronal proliferation, whereas during adulthood it could produce ERG supernormality as well as altered circadian rhythms, dark/light adaptation and spatial contrast sensitivity. -- Highlights: ► Peak [BPb] in control, low-, moderate- and high-dose newborn mice with gestational lead exposure: ≤ 1, ≤ 10, 25 and 40 μg/dL ► Gestational lead exposure dose-dependently decreased the number of TH

  4. Long-term dietary exposure to lead in young European children: Comparing a pan-European approach with a national exposure assessment

    DEFF Research Database (Denmark)

    Boon, P.E.; Te Biesebeek, J.D.; van Klaveren, J.D.

    2012-01-01

    Long-term dietary exposures to lead in young children were calculated by combining food consumption data of 11 European countries categorised using harmonised broad food categories with occurrence data on lead from different Member States (pan-European approach). The results of the assessment...... in children living in the Netherlands were compared with a long-term lead intake assessment in the same group using Dutch lead concentration data and linking the consumption and concentration data at the highest possible level of detail. Exposures obtained with the pan-European approach were higher than...... the national exposure calculations. For both assessments cereals contributed most to the exposure. The lower dietary exposure in the national study was due to the use of lower lead concentrations and a more optimal linkage of food consumption and concentration data. When a pan-European approach, using...

  5. Food contamination as a pathway for lead exposure in children during the 2010-2013 lead poisoning epidemic in Zamfara, Nigeria.

    Science.gov (United States)

    Tirima, Simba; Bartrem, Casey; von Lindern, Ian; von Braun, Margrit; Lind, Douglas; Anka, Shehu Mohamed; Abdullahi, Aishat

    2018-05-01

    In 2010, an estimated 400 to 500 children died of acute lead poisoning associated with artisanal gold mining in Zamfara, Nigeria. Processing of gold ores containing up to 10% lead within residential compounds put residents, especially children, at the highest risk. Principal routes of exposure were incidental ingestion and inhalation of contaminated soil and dusts. Several Nigerian and international health organizations collaborated to reduce lead exposures through environmental remediation and medical treatment. The contribution of contaminated food to total lead exposure was assessed during the environmental health response. Objectives of this investigation were to assess the influence of cultural/dietary habits on lead exposure pathways and estimate the contribution of contaminated food to children's blood lead levels (BLLs). A survey of village dietary practices and staple food lead content was conducted to determine dietary composition, caloric intakes, and lead intake. Potential blood lead increments were estimated using bio-kinetic modeling techniques. Most dietary lead exposure was associated with contamination of staple cereal grains and legumes during post-harvest processing and preparation in contaminated homes. Average post-harvest and processed cereal grain lead levels were 0.32mg/kg and 0.85mg/kg dry weight, respectively. Age-specific food lead intake ranged from 7 to 78μg/day. Lead ingestion and absorption were likely aggravated by the dusty environment, fasting between meals, and nutritional deficiencies. Contamination of staple cereal grains by highly bioavailable pulverized ores could account for as much as 11%-34% of children's BLLs during the epidemic, and were a continuing source after residential soil remediation until stored grain inventories were exhausted. Copyright © 2017. Published by Elsevier B.V.

  6. Biomonitoring of the mycotoxin Zearalenone: current state-of-the art and application to human exposure assessment.

    Science.gov (United States)

    Mally, Angela; Solfrizzo, Michele; Degen, Gisela H

    2016-06-01

    Zearalenone (ZEN), a mycotoxin with high estrogenic activity in vitro and in vivo, is a widespread food contaminant that is commonly detected in maize, wheat, barley, sorghum, rye and other grains. Human exposure estimates based on analytical data on ZEN occurrence in various food categories and food consumption data suggest that human exposure to ZEN and modified forms of ZEN may be close to or even exceed the tolerable daily intake (TDI) derived by the European Food Safety Authority (EFSA) for some consumer groups. Considering the inherent uncertainties in estimating dietary intake of ZEN that may lead to an under- or overestimation of ZEN exposure and consequently human risk and current lack of data on vulnerable consumer groups, there is a clear need for more comprehensive and reliable exposure data to refine ZEN risk assessment. Human biomonitoring (HBM) is increasingly being recognized as an efficient and cost-effective way of assessing human exposure to food contaminants, including mycotoxins. Based on animal and (limited) human data on the toxicokinetics of ZEN, it appears that excretion of ZEN and its major metabolites may present suitable biomarkers of ZEN exposure. In view of the limitations of available dietary exposure data on ZEN and its modified forms, the purpose of this review is to provide an overview of recent studies utilizing HBM to monitor and assess human exposure to ZEN. Considerations are given to animal and human toxicokinetic data relevant to HBM, analytical methods, and available HBM data on urinary biomarkers of ZEN exposure in different cohorts.

  7. Series Production of 13 kA Current Leads with Dry and Compact Warm Terminals

    CERN Document Server

    Andersen, T P; Vullierme, B

    2005-01-01

    For the LHC magnet test benches 13 pairs of conventional helium vapour-cooled 13 kA current leads are required. The current leads have been designed and built by industry. Attention was given to economical and reliable design and to a design of the warm terminal in order to avoid any condensation. Three pairs of them were tested at CERN. The dry warm terminal enables voltage test at 4.1 kV at cold condition. The paper describes construction details and compares calculated and measured values of the main parameters.

  8. Cadmium, lead, and mercury exposure assessment among croatian consumers of free-living game.

    Science.gov (United States)

    Lazarus, Maja; Prevendar Crnić, Andreja; Bilandžić, Nina; Kusak, Josip; Reljić, Slaven

    2014-09-29

    Free-living game can be an important source of dietary cadmium and lead; the question is whether exposure to these two elements is such that it might cause adverse health effects in the consumers. The aim of this study was to estimate dietary exposure to cadmium, lead, and mercury from free-living big game (fallow deer, roe deer, red deer, wild boar, and brown bear), and to mercury from small game (pheasant and hare), hunted in Croatia from 1990 to 2012. The exposure assessment was based on available literature data and our own measurements of metal levels in the tissues of the game, by taking into account different consumption frequencies (four times a year, once a month and once a week). Exposure was expressed as percentage of (provisional) tolerable weekly intake [(P)TWI] values set by the European Food Safety Authority (EFSA). Consumption of game meat (0.002-0.5 % PTWI) and liver (0.005-6 % PTWI) assumed for the general population (four times a year) does not pose a health risk to consumers from the general population, nor does monthly (0.02-6 % PTWI) and weekly (0.1-24 % PTWI) consumption of game meat. However, because of the high percentage of free-living game liver and kidney samples exceeding the legislative limits for cadmium (2-99 %) and lead (1-82 %), people should keep the consumption of certain game species' offal as low as possible. Children and pregnant and lactating women should avoid eating game offal altogether. Free-living game liver could be an important source of cadmium if consumed on a monthly basis (3-74 % TWI), and if consumed weekly (11-297 % TWI), it could even give rise to toxicological concern.

  9. Prenatal maternal stress in relation to the effects of prenatal lead exposure on toddler cognitive development.

    Science.gov (United States)

    Zhou, Leilei; Xu, Jian; Zhang, Jinsong; Yan, Chonghuai; Lin, Yanfen; Jia, Yinan; Hu, Wenjing

    2017-03-01

    To evaluate the effects of maternal lead exposure during pregnancy on toddler cognitive development and the potential effect modification by maternal stress. We conducted a prospective birth-cohort study in Shanghai from 2010 to 2012 and investigated 225 mother-infant pairs. The mothers were recruited in mid-to-late pregnancy and children were followed up until 24-36 months old. A self-administered Symptom Checklist-90-Revised Scale (SCL-90-R) was used to assess maternal emotional stress during pregnancy. Maternal whole blood lead levels were measured during gestational weeks 28-36. The toddlers' cognitive levels were assessed using the Gesell Development Scale. Multiple linear regression models were established to explore the main effects of prenatal lead exposure on toddlers' cognitive abilities and the modifying effects of maternal stress. Covariate information was collected through interviews, questionnaires and medical records. The mean maternal blood lead concentration was 3.30 (95%CI: 3.05, 3.57) μg/dL. After adjusting for relevant confounders, no significant associations of maternal blood lead concentrations with toddlers' cognitive levels were observed in all five domains of the Gesell scale (P>0.05). However, the interaction between prenatal maternal blood lead and stress was significant in the domains of adaptive behavior, language and social behavior. When stratified by maternal stress levels, compared with non-significant associations (P>0.05) among low (P1-P75) prenatal stress group, adverse associations between maternal blood lead concentrations (log10-transformed) and toddlers' cognitive levels were observed among high (P75-P100) prenatal stress group in the domains of language (β=-33.82, 95%CI: -60.04, -7.59), social behavior (β=-41.00, 95%CI: -63.11, -18.89) and adaptive behavior (β=-17.93, 95%CI: -35.83, -0.03). Prenatal maternal stress may exacerbate the deleterious effects of prenatal exposure to lead on toddler cognitive development

  10. Lead exposure is related to hypercortisolemic profiles and allostatic load in Brazilian older adults

    Energy Technology Data Exchange (ETDEWEB)

    Souza-Talarico, Juliana N., E-mail: junery@usp.br [Department of Medical-Surgical Nursing, School of Nursing, Universidade de São Paulo, São Paulo 05403 000 (Brazil); Suchecki, Deborah [Department of Psychobiology, Universidade Federal de São Paulo, São Paulo 04023-062 (Brazil); Juster, Robert-Paul [Department of Psychiatry, Columbia University Medical Center, New York, NY 10032 (United States); Plusquellec, Pierrich [Centre for Studies on Human Stress, Mental Health University Institute, Department of Psychiatry, University of Montreal, QC, Canada H1N 3V2 (Canada); School of Psychoeducation, Université de Montréal, Montreal, QC, Canada J1K 2R1 (Canada); Barbosa Junior, Fernando [Department of Clinical Chemistry and Toxicology, School of Pharmaceutical Sciences of Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto 14040903 (Brazil); Bunscheit, Vinícius [Department of Psychobiology, Universidade Federal de São Paulo, São Paulo 04023-062 (Brazil); Marcourakis, Tania [Department of Clinical Chemistry and Toxicology, School of Pharmaceutical Sciences, Universidade de São Paulo, São Paulo 05508-000 (Brazil); Martins de Matos, Tatiane [Department of Medical-Surgical Nursing, School of Nursing, Universidade de São Paulo, São Paulo 05403 000 (Brazil); Lupien, Sonia J. [Centre for Studies on Human Stress, Mental Health University Institute, Department of Psychiatry, University of Montreal, QC, Canada H1N 3V2 (Canada)

    2017-04-15

    Lead levels (Pb) have been linked to both hyper- and hypo-reactivity of hypothalamic-pituitary-adrenal axis (HPA) axis to acute stress in animals and humans. Similarly, allostatic load (AL), the ‘wear and tear’ of chronic stress, is associated with inadequate HPA axis activity. We examined whether Pb levels would be associated with altered diurnal cortisol profile, as a primary mediator of AL, during aging. Pb levels were measured from blood samples (BPb) of 126 Brazilian individuals (105 women), between 50 and 82 years old. Six neuroendocrine, metabolic, and anthropometric biomarkers were analyzed and values were transformed into an AL index using clinical reference cut-offs. Salivary samples were collected at home over 2 days at awakening, 30-min after waking, afternoon, and evening periods to determine cortisol levels. A multiple linear regression model showed a positive association between BPb as the independent continuous variable and cortisol awakening response (R{sup 2}=0.128; B=0.791; p=0.005) and overall cortisol concentration (R{sup 2}=0.266; B=0.889; p<0.001) as the outcomes. Repeated measures ANOVA showed that individuals with high BPb levels showed higher cortisol at 30 min after awakening (p=0.003), and in the afternoon (p=0.002) than those with low BPb values. Regarding AL, regression model showed that BPb was positively associated with AL index (R{sup 2}=0.100; B=0.204; p=0.032). Correlation analyzes with individual biomarkers showed that BPb was positively correlated with HDL cholesterol (p=0.02) and negatively correlated with DHEA-S (p=0.049). These findings suggest that Pb exposure, even at levels below the reference blood lead level for adults recommended by the National Institute for Occupational Safety and Health and by the Center for Disease Control and Prevention, may contribute to AL and dysregulated cortisol functioning in older adults. Considering these findings were based on cross-sectional data future research is needed to confirm

  11. Exposure to PM2.5 and Blood Lead Level in Two Populations in Ulaanbaatar, Mongolia.

    Science.gov (United States)

    Enkhbat, Undarmaa; Rule, Ana M; Resnick, Carol; Ochir, Chimedsuren; Olkhanud, Purevdorj; Williams, D'Ann L

    2016-02-15

    Approximately 60% of the households in Ulaanbaatar live in gers (a traditional Mongolian dwelling) in districts outside the legal limits of the city, without access to basic infrastructure, such as water, sewage systems, central heating, and paved roads, in contrast to apartment residents. This stark difference in living conditions creates different public health challenges for Ulaanbaatar residents. Through this research study we aim to test our hypothesis that women living in gers burning coal in traditional stoves for cooking and heating during the winter are exposed to higher concentrations of airborne PM2.5 than women living in apartments in Ulaanbaatar, Mongolia, and this exposure may include exposures to lead in coal with effects on blood lead levels. This cross-sectional study recruited a total of 50 women, 40-60 years of age, from these two settings. Air sampling was carried out during peak cooking and heating times, 5:00 p.m.-11:00 p.m., using a direct-reading instrument (TSI SidePak™) and integrated polytetrafluoroethylene (PTFE) filters using the SKC Personal Environmental Monitor. Blood lead level (BLL) was measured using a LeadCare II rapid field test method. In our study population, measured PM2.5 geometric mean (GM) concentrations using the SidePak™ in the apartment group was 31.5 (95% CI:17-99) μg/m³, and 100 (95% CI: 67-187) μg/m³ in ger households (p < 0.001). The GM integrated gravimetric PM2.5 concentrations in the apartment group were 52.8 (95% CI: 39-297) μg/m³ and 127.8 (95% CI: 86-190) μg/m³ in ger households (p = 0.004). The correlation coefficient for the SidePak™ PM2.5 concentrations and filter based PM2.5 concentrations was r = 0.72 (p < 0.001). Blood Lead Levels were not statistically significant different between apartment residents and ger residents (p = 0.15). The BLL is statistically significant different (p = 0.01) when stratified by length of exposures outside of the home. This statistically significant difference

  12. Lead exposure is related to hypercortisolemic profiles and allostatic load in Brazilian older adults

    International Nuclear Information System (INIS)

    Souza-Talarico, Juliana N.; Suchecki, Deborah; Juster, Robert-Paul; Plusquellec, Pierrich; Barbosa Junior, Fernando; Bunscheit, Vinícius; Marcourakis, Tania; Martins de Matos, Tatiane; Lupien, Sonia J.

    2017-01-01

    Lead levels (Pb) have been linked to both hyper- and hypo-reactivity of hypothalamic-pituitary-adrenal axis (HPA) axis to acute stress in animals and humans. Similarly, allostatic load (AL), the ‘wear and tear’ of chronic stress, is associated with inadequate HPA axis activity. We examined whether Pb levels would be associated with altered diurnal cortisol profile, as a primary mediator of AL, during aging. Pb levels were measured from blood samples (BPb) of 126 Brazilian individuals (105 women), between 50 and 82 years old. Six neuroendocrine, metabolic, and anthropometric biomarkers were analyzed and values were transformed into an AL index using clinical reference cut-offs. Salivary samples were collected at home over 2 days at awakening, 30-min after waking, afternoon, and evening periods to determine cortisol levels. A multiple linear regression model showed a positive association between BPb as the independent continuous variable and cortisol awakening response (R 2 =0.128; B=0.791; p=0.005) and overall cortisol concentration (R 2 =0.266; B=0.889; p<0.001) as the outcomes. Repeated measures ANOVA showed that individuals with high BPb levels showed higher cortisol at 30 min after awakening (p=0.003), and in the afternoon (p=0.002) than those with low BPb values. Regarding AL, regression model showed that BPb was positively associated with AL index (R 2 =0.100; B=0.204; p=0.032). Correlation analyzes with individual biomarkers showed that BPb was positively correlated with HDL cholesterol (p=0.02) and negatively correlated with DHEA-S (p=0.049). These findings suggest that Pb exposure, even at levels below the reference blood lead level for adults recommended by the National Institute for Occupational Safety and Health and by the Center for Disease Control and Prevention, may contribute to AL and dysregulated cortisol functioning in older adults. Considering these findings were based on cross-sectional data future research is needed to confirm our

  13. Exposure to PM2.5 and Blood Lead Level in Two Populations in Ulaanbaatar, Mongolia

    Directory of Open Access Journals (Sweden)

    Undarmaa Enkhbat

    2016-02-01

    Full Text Available Approximately 60% of the households in Ulaanbaatar live in gers (a traditional Mongolian dwelling in districts outside the legal limits of the city, without access to basic infrastructure, such as water, sewage systems, central heating, and paved roads, in contrast to apartment residents. This stark difference in living conditions creates different public health challenges for Ulaanbaatar residents. Through this research study we aim to test our hypothesis that women living in gers burning coal in traditional stoves for cooking and heating during the winter are exposed to higher concentrations of airborne PM2.5 than women living in apartments in Ulaanbaatar, Mongolia, and this exposure may include exposures to lead in coal with effects on blood lead levels. This cross-sectional study recruited a total of 50 women, 40–60 years of age, from these two settings. Air sampling was carried out during peak cooking and heating times, 5:00 p.m.–11:00 p.m., using a direct-reading instrument (TSI SidePak™ and integrated polytetrafluoroethylene (PTFE filters using the SKC Personal Environmental Monitor. Blood lead level (BLL was measured using a LeadCare II rapid field test method. In our study population, measured PM2.5 geometric mean (GM concentrations using the SidePak™ in the apartment group was 31.5 (95% CI:17–99 μg/m3, and 100 (95% CI: 67–187 μg/m3 in ger households (p < 0.001. The GM integrated gravimetric PM2.5 concentrations in the apartment group were 52.8 (95% CI: 39–297 μg/m3 and 127.8 (95% CI: 86–190 μg/m3 in ger households (p = 0.004. The correlation coefficient for the SidePak™ PM2.5 concentrations and filter based PM2.5 concentrations was r = 0.72 (p < 0.001. Blood Lead Levels were not statistically significant different between apartment residents and ger residents (p = 0.15. The BLL is statistically significant different (p = 0.01 when stratified by length of exposures outside of the home. This statistically

  14. Association of umbilical cord blood lead with neonatal behavior at varying levels of exposure

    Directory of Open Access Journals (Sweden)

    Mamtani Manju R

    2006-06-01

    Full Text Available Abstract Background In the light of the ongoing debate about lowering the cut-off for acceptable blood lead level to Methods Using Brazelton's Neonatal Behavioral Assessment Scale (NBAS, an epidemiological approach and robust statistical techniques like multivariate linear regression, logistic regression, Poisson regression and structural equations modeling analyses we estimated the simultaneous indirect effects of umbilical cord blood lead (CBL levels and other neonatal covariates on the NBAS clusters. Results We observed that when analyzed in all study subjects, the CBL levels independently and strongly influenced autonomic stability and abnormal reflexes clusters. However, when the analysis was restricted to neonates with CBL Conclusion Our results further endorse the need to be cognizant of the detrimental effects of blood lead on neonates even at a low-dose prenatal exposure.

  15. Sub-chronic lead exposure produces β1-adrenoceptor downregulation decreasing arterial pressure reactivity in rats.

    Science.gov (United States)

    Toscano, Cindy Medici; Simões, Maylla Ronacher; Alonso, Maria Jesus; Salaices, Mercedes; Vassallo, Dalton Valentim; Fioresi, Mirian

    2017-07-01

    Lead is considered a causative factor for hypertension and other cardiovascular diseases. To investigate the effects of sub-chronic lead exposure on blood pressure reactivity and cardiac β 1 -adrenoceptor activity and to evaluate whether the effects found in vitro are similar to those found in vivo. Male Wistar rats were randomly distributed into two groups: control rats (Ct) and rats administered drinking water containing 100ppm lead (Pb) for 30days. Blood pressure in the Pb rats increased starting from the first week of treatment until the end of the study [systolic blood pressure, Ct: 122±4 vs. Pb: 143±3mmHg; diastolic blood pressure, Ct: 63±4 vs. Pb: 84±4mmHg]. The heart rate was also increased (Ct: 299±11 vs. Pb: 365±11bpm), but the pressure reactivity to phenylephrine was decreased. Losartan and hexamethonium exhibited a greater reduction in blood pressure of Pb rats than in the Ct rats. Isoproterenol increased the left ventricular systolic and end-diastolic pressure, and heart rate only in Ct rats, suggesting that lead induced β 1 -adrenoceptor downregulation. Indomethacin reduced the blood pressure and heart rate in the Pb rats, suggesting the involvement of cyclooxygenase-derived products (which are associated with reduced nitric oxide bioavailability) in this process. These findings offer further evidence that the effects of sub-chronic lead exposure in vitro can be reproduced in vivo-even at low concentrations-thus triggering mechanisms for the development of hypertension. Therefore, lead should be considered an environmental risk factor for cardiovascular disease. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Effects of sublethal exposure to lead on levels of energetic compounds in Procambarus clarkii (Girard, 1852)

    Energy Technology Data Exchange (ETDEWEB)

    Martinez, M.; Torreblanca, A.; Del Ramo, J.; Diaz-Mayans, J. (Univ. of Valencia (Spain))

    1994-05-01

    Lead is neither essential nor beneficial to living organisms; all existing data show that its metabolic effects are adverse. Lead is toxic to all phyla of aquatic biota. Most of the lead discharged into surface water is rapidly incorporated into suspended and bottom sediments. The American red crayfish, Procambarus clarkii, lives in a wide range of environmental conditions that include highly polluted waters. Lead present in take sediments can be available to aquatic animals such as P. clarkii because it is a detritivor and burrow into the sediment. In fact, we found remarkable levels of lead in tissues of P. clarkii caught in Albufera Lake and kept 15 days in clean water (e. g. 223 [mu]g/g dry weight in gills). Furthermore, P. clarkii has a high capacity for lead accumulation from water, and gills were the most important tissue of lead accumulation. Among effects that contaminants have on the physiology of the organisms, energetic state variables are important, since they will alter both survival and reproduction. Hepatopancreas is a major site for the energetic reserve in crayfish and is a site of lead accumulation, although metal concentration in this organ is not as high as gills. The purpose of this study was to examine changes in energy reserves in hepatopancreas and gills of the crayfish P. clarkii, in response to sublethal exposure to lead. Gills are directly exposed to contaminants in the environment, and they are the first organ showing alterations by the action of the contaminants. Hepatopancreas was also chosen due to both, its relevance in the energetic metabolism and its role in heavy metal detoxification mechanisms.

  17. Effect of lead exposure on serum estradiol and certain haematological indices in female rats

    International Nuclear Information System (INIS)

    Abd El-Moneim, A.E.; El-Abiad, N.M.

    1996-01-01

    In this study, graded dosages of lead acetate (Pb Ac) 0,100,200 and 500 mg/liter were dissolved in tap water and offered freely to four groups of female rats to show the effect of lead (Pb) ingestion on serum estradiol (E 2 ) concentration. Changes in body weight (B.wt), relative liver, kidney, spleen weights were recorded. Blood lead content, red blood cells (RBC), white blood cells (WBC) counts, blood hemoglobin (Hb) content and hematocrit values were measured as indicators of elevated Pb exposure. After three months of treatment, as compared to control animals, all lead-treated rats showed a significant decrease in B.wt and significant increase in relative weights of liver and spleen. Kidney relative weight did not indicate significant differences between rats given tap water with or without Pb Ac. Blood Pb content and WBC count were higher and RBC count was lower in rats given leaded water. Both Hb and Hct values were insignificantly reduced in lead exposed rats. The treatment with 500 mg Pb Ac/liter of drinking water resulted in significant fall of serum E 2 to reach about half its value control group at end of the experiment, while, the decrease in serum E 2 was less significant in the group received 200 mg Pb Ac/liter tap water. 2 tabs

  18. Purification and concentration of lead samples in biological monitoring of occupational exposures

    Directory of Open Access Journals (Sweden)

    A Rahimi-Froushani

    2006-04-01

    Full Text Available Background and Aims:Lead is an important environmental constituent widely used in industrialprocesses for production of synthetic materials and therefore can be released in the environmentcausing public exposure especially around the industrial residence area. For evaluation of humanexposure to trace toxic metal of Pb (II, environmental and biological monitoring are essentialprocesses, in which, preparation of such samples is one of the most time-consuming and errorproneaspects prior to analysis. The use of solid-phase extraction (SPE has grown and is a fertiletechnique of sample preparation as it provides better results than those produced by liquid-liquidextraction (LLE. The aim of this study was to investigate factors influencing sample pretreatmentfor trace analysis of lead in biological samples for evaluation of occupational exposure.Method :To evaluate factors influencing quantitative analysis scheme of lead, solid phaseextraction using mini columns filled with XAD-4 resin was optimized with regard to sample pH,ligand concentration, loading flow rate, elution solvent, sample volume (up to 500 ml, elutionvolume, amount of resins, and sample matrix interferences.Results :Lead was retained on solid sorbent and eluted followed by simple determination ofanalytes by using flame atomic absorption spectrometery. Obtained recoveries of the metal ionwere more than 92%. The amount of the analyte detected after simultaneous pre-concentrationwas basically in agreement with the added amounts. The optimized procedure was also validatedwith three different pools of spiked urine samples and showed a good reproducibility over sixconsecutive days as well as six within-day experiments. The developed method promised to beapplicable for evaluation of other metal ions present in different environmental and occupationalsamples as suitable results were obtained for relative standard deviation (less than 10%.Conclusion:This optimized method can be considered to be

  19. Hearing loss in children with e-waste lead and cadmium exposure.

    Science.gov (United States)

    Liu, Yu; Huo, Xia; Xu, Long; Wei, Xiaoqin; Wu, Wengli; Wu, Xianguang; Xu, Xijin

    2018-05-15

    Environmental chemical exposure can cause neurotoxicity and has been recently linked to hearing loss in general population, but data are limited in early life exposure to lead (Pb) and cadmium (Cd) especially for children. We aimed to evaluate the association of their exposure with pediatric hearing ability. Blood Pb and urinary Cd were collected form 234 preschool children in 3-7years of age from an electronic waste (e-waste) recycling area and a reference area matched in Shantou of southern China. Pure-tone air conduction (PTA) was used to test child hearing thresholds at frequencies of 0.25, 0.5, 1, 2, 4 and 8kHz. A PTA≥25dB was defined as hearing loss. A higher median blood Pb level was found in the exposed group (4.94±0.20 vs 3.85±1.81μg/dL, phearing loss (28.8% vs 13.6%, phearing thresholds at average low and high frequency, and single frequency of 0.5, 1 and 2kHz were all increased in the exposed group. Positive correlations of child age and nail biting habit with Pb, and negative correlations of parent education level and child washing hands before dinner with Pb and Cd exposure were observed. Logistic regression analyses showed the adjusted OR of hearing loss for Pb exposure was 1.24 (95% CI: 1.029, 1.486). Our data suggest that early childhood exposure to Pb may be an important risk factor for hearing loss, and the developmental auditory system might be affected in e-waste polluted areas. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Lead exposures and biological responses in military weapons systems: Aerosol characteristics and acute lead effects among US Army artillerymen: Final report

    Energy Technology Data Exchange (ETDEWEB)

    Bhattacharyya, M.H.; Stebbings, J.H.; Peterson, D.P.; Johnson, S.A.; Kumar, R.; Goun, B.D.; Janssen, I.; Trier, J.E.

    1993-03-01

    This study was to determine the concentration and chemical nature of lead (Pb) aerosols produced during the firing of artillery and to determine the exposures and biological responses of crew members exposed to lead aerosols during such firing. The concentrations of lead-containing aerosols at crew positions depended on wind conditions, with higher concentrations when firing into a head wind. Aerosol concentrations were highest in the muzzle blast zone. Concentrations of lead in the blood of crew members rose during the first 12 days of exposure to elevated airborne lead concentrations and then leveled off. There was no rapid decrease in blood lead concentrations after completion of firing. Small decreases in hematocrit and small increases in free erythrocyte porphyrin were correlated with increasing exposure to airborne lead. These changes were reversed by seven weeks after firing. Changes in nerve conduction velocity had borderline statistical significance to airborne lead exposure. In measuring nerve conduction velocity, differences in skin temperature must be taken into account.

  1. Effect of vitamin E on lead exposure-induced learning and memory impairment in rats.

    Science.gov (United States)

    Khodamoradi, Nasrin; Komaki, Alireza; Salehi, Iraj; Shahidi, Siamak; Sarihi, Abdolrahman

    2015-05-15

    Chronic lead (Pb(2+)) exposure has been associated with learning and memory impairments, whereas vitamin E improves cognitive deficits. In this study, using a passive avoidance learning model in rats, we investigated the effects of vitamin E on Pb(2+) exposure-induced learning and memory impairments in rats. In the present study, 56 Wistar male rats (weighting 230-250g) were divided into eight groups (n=7). The Pb(2+) exposure involved gavages of lead acetate solution using three different doses (0.05%, 0.1%, and 0.2%) and the vitamin E consisted of three different doses (10, 25, 50μg/rat) for 30days. After the 30-day period, the rats were tested using a passive avoidance task (acquisition test). In a retrieval test conducted 48h after the training, step through latency (STL) and time in the dark compartment (TDC) were recorded. The statistical analysis of data was performed using ANOVA followed by Tukey's post hoc analysis. In all cases, differences were considered significant if plearning and the TDC, whereas it decreased the STL in the passive avoidance test. Administration of vitamin E ameliorated the effects of Pb(2+) on animal behavior in the passive avoidance learning and memory task. Our results indicate that impairments of learning and memory in Pb(2+)-exposed rats are dose dependent and can be inhibited by antioxidants such as vitamin E. Copyright © 2015 Elsevier Inc. All rights reserved.

  2. Environmental Exposure to Arsenic, Lead, and Cadmium in People Living near Janghang Copper Smelter in Korea.

    Science.gov (United States)

    Kim, Yong-Dae; Eom, Sang-Yong; Yim, Dong-Hyuk; Kim, In-Soo; Won, Hee-Kwan; Park, Choong-Hee; Kim, Guen-Bae; Yu, Seung-Do; Choi, Byung-Sun; Park, Jung-Duck; Kim, Heon

    2016-04-01

    Concentrations of heavy metals exceed safety thresholds in the soil near Janghang Copper Refinery, a smelter in Korea that operated from 1936 to 1989. This study was conducted to evaluate the level of exposure to toxic metals and the potential effect on health in people living near the smelter. The study included 572 adults living within 4 km of the smelter and compared them with 413 controls group of people living similar lifestyles in a rural area approximately 15 km from the smelter. Urinary arsenic (As) level did not decrease according to the distance from the smelter, regardless of gender and working history in smelters and mines. However, in subjects who had no occupational exposure to toxic metals, blood lead (Pb) and cadmium (Cd) and urinary Cd decreased according to the distance from the smelter, both in men and women. Additionally, the distance from the smelter was a determinant factor for a decrease of As, Pb, and Cd in multiple regression models, respectively. On the other hands, urinary Cd was a risk factor for renal tubular dysfunction in populations living near the smelter. These results suggest that Janghang copper smelter was a main contamination source of As, Pb, and Cd, and populations living near the smelter suffered some adverse health effects as a consequence. The local population should be advised to make efforts to reduce exposure to environmental contaminants, in order to minimize potential health effects, and to pay close attention to any health problems possibly related to toxic metal exposure.

  3. Perinatal exposure to lead induces morphological, ultrastructural and molecular alterations in the hippocampus

    International Nuclear Information System (INIS)

    Baranowska-Bosiacka, I.; Strużyńska, L.; Gutowska, I.; Machalińska, A.; Kolasa, A.; Kłos, P.; Czapski, G.A.; Kurzawski, M.; Prokopowicz, A.; Marchlewicz, M.

    2013-01-01

    Highlights: ► Pre- and neonatal Pb exposure decreased the number of hippocampal neurons. ► Lead caused ultrastructural alterations in CA1 region of hippocampus. ► Hippocampus is highly vulnerable to low level perinatal Pb exposure. ► Lead decreased BDNF level in the developing brain. ► Decreased Bax/Bcl2 ratio may protect hippocampus against Pb-induced apoptosis. -- Abstract: The aim of this paper is to examine if pre- and neonatal exposure to lead (Pb) may intensify or inhibit apoptosis or necroptosis in the developing rat brain. Pregnant experimental females received 0.1% lead acetate (PbAc) in drinking water from the first day of gestation until weaning of the offspring; the control group received distilled water. During the feeding of pups, mothers from the experimental group were still receiving PbAc. Pups were weaned at postnatal day 21 and the young rats of both groups then received only distilled water until postnatal day 28. This treatment protocol resulted in a concentration of Pb in rat offspring whole blood (Pb-B) below the threshold of 10 μg/dL, considered safe for humans.We studied Casp-3 activity and expression, AIF nuclear translocation, DNA fragmentation, as well as Bax, Bcl-2 mRNA and protein expression as well as BDNF concentration in selected structures of the rat brain: forebrain cortex (FC), cerebellum (C) and hippocampus (H). The microscopic examinations showed alterations in hippocampal neurons.Our data shows that pre- and neonatal exposure of rats to Pb, leading to Pb-B below 10 μg/dL, can decrease the number of hippocampus neurons, occurring concomitantly with ultrastructural alterations in this region. We observed no morphological or molecular features of severe apoptosis or necrosis (no active Casp-3 and AIF translocation to nucleus) in young brains, despite the reduced levels of BDNF. The potential protective factor against apoptosis was probably the decreased Bax/Bcl-2 ratio, which requires further investigation. Our

  4. IMPLICATIONS OF THE CURRENT EXPOSURE DRAFT ON AUDIT REPORTING

    Directory of Open Access Journals (Sweden)

    George Silviu CORDOȘ

    2015-04-01

    Full Text Available The regulatory changes come as a response to perceived deficiencies in the postfinancial crisis, and their goal is to improve users' perception of the usefulness and quality of the audit report. The article approaches the subject of these proposals to revise the standards and their implications for the audit report. The article is divided into five parts: the first part the authors present a brief introduction to the subject matter; the second part presents the research methodology; the third part the authors present a review of the literature research; the fourth section presents an analysis of the responses of EU respondents to the Exposure Draft issued by the IAASB in July 2013 and the last part the authors present research findings, limitations and perspectives.

  5. Chronic lead exposure decreases the vascular reactivity of rat aortas: the role of hydrogen peroxide.

    Directory of Open Access Journals (Sweden)

    Karolini Zuqui Nunes

    Full Text Available We investigated whether exposure to small concentrations of lead alters blood pressure and vascular reactivity. Male Wistar rats were sorted randomly into the following two groups: control (Ct and treatment with 100 ppm of lead (Pb, which was added to drinking water, for 30 days. Systolic blood pressure (BP was measured weekly. Following treatment, aortic ring vascular reactivity was assessed. Tissue samples were properly stored for further biochemical investigation. The lead concentration in the blood reached approximately 8 μg/dL. Treatment increased blood pressure and decreased the contractile responses of the aortic rings to phenylephrine (1 nM-100 mM. Following N-nitro-L arginine methyl ester (L-NAME administration, contractile responses increased in both groups but did not differ significantly between them. Lead effects on Rmax were decreased compared to control subjects following superoxide dismutase (SOD administration. Catalase, diethyldithiocarbamic acid (DETCA, and apocynin increased the vasoconstrictor response induced by phenylephrine in the aortas of lead-treated rats but did not increase the vasoconstrictor response in the aortas of untreated rats. Tetraethylammonium (TEA potentiated the vasoconstrictor response induced by phenylephrine in aortic segments in both groups, but these effects were greater in lead-treated rats. The co-incubation of TEA and catalase abolished the vasodilatory effect noted in the lead group. The present study is the first to demonstrate that blood lead concentrations well below the values established by international legislation increased blood pressure and decreased phenylephrine-induced vascular reactivity. The latter effect was associated with oxidative stress, specifically oxidative stress induced via increases in hydrogen peroxide levels and the subsequent effects of hydrogen peroxide on potassium channels.

  6. 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?

    International Nuclear Information System (INIS)

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

    2015-01-01

    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. - Highlights: • Pb isotopes of environmental media and children's blood and urine were analyzed. • Pb exposure and pollution source were studied in lead-acid battery and coking areas. • Pb isotope ratios in blood and urine were similar to those of food, water and PM. • Urine Pb level may not be used as a proxy for indicating the lead levels in blood. • Urine Pb isotope ratios is an alternative to identify source and exposure pathways. - Urinary lead is not a preferable proxy to estimate blood lead level, but urinary lead isotope ratios could be an alternative for identifying the sources of lead exposure in children

  7. Lead Exposure Impairs Hippocampus Related Learning and Memory by Altering Synaptic Plasticity and Morphology During Juvenile Period.

    Science.gov (United States)

    Wang, Tao; Guan, Rui-Li; Liu, Ming-Chao; Shen, Xue-Feng; Chen, Jing Yuan; Zhao, Ming-Gao; Luo, Wen-Jing

    2016-08-01

    Lead (Pb) is an environmental neurotoxic metal. Pb exposure may cause neurobehavioral changes, such as learning and memory impairment, and adolescence violence among children. Previous animal models have largely focused on the effects of Pb exposure during early development (from gestation to lactation period) on neurobehavior. In this study, we exposed Sprague-Dawley rats during the juvenile stage (from juvenile period to adult period). We investigated the synaptic function and structural changes and the relationship of these changes to neurobehavioral deficits in adult rats. Our results showed that juvenile Pb exposure caused fear-conditioned memory impairment and anxiety-like behavior, but locomotion and pain behavior were indistinguishable from the controls. Electrophysiological studies showed that long-term potentiation induction was affected in Pb-exposed rats, and this was probably due to excitatory synaptic transmission impairment in Pb-exposed rats. We found that NMDA and AMPA receptor-mediated current was inhibited, whereas the GABA synaptic transmission was normal in Pb-exposed rats. NR2A and phosphorylated GluR1 expression decreased. Moreover, morphological studies showed that density of dendritic spines declined by about 20 % in the Pb-treated group. The spine showed an immature form in Pb-exposed rats, as indicated by spine size measurements. However, the length and arborization of dendrites were unchanged. Our results suggested that juvenile Pb exposure in rats is associated with alterations in the glutamate receptor, which caused synaptic functional and morphological changes in hippocampal CA1 pyramidal neurons, thereby leading to behavioral changes.

  8. Predictors of environmental lead exposure among pregnant women – a prospective cohort study in Poland

    Directory of Open Access Journals (Sweden)

    Kinga Polańska

    2014-03-01

    Full Text Available Blood lead levels (BLL in women of child-bearing age have been decreasing in recent decades, but still remains a concern for long-term effects of child psychomotor development. The aim of the study was to characterize lead exposure among Polish pregnant women and assess the relationship between BLL and selected socio-demographic, economic and lifestyle factors. The study population consisted of 594 pregnant women who had been the subjects of the prospective Polish Mother and Child Cohort Study (REPRO_PL. The women were interviewed three times during pregnancy (once in each trimester. Lead concentration in the blood collected during the second trimester of pregnancy was analyzed using graphite furnace atomic absorption spectrometry (GF-AAS, or inductively coupled plasma mass spectrometry (ICP-MS. Active and passive smoking was analyzed by the cotinine level in saliva using liquid chromatography with tandem mass spectrometry (LC-MS/MS. The lead level in the blood ranged from 0.3 – 5.7 μg/dL, with a geometric mean (GM of 1.1 μg/dL (GSD }0.2 μg/dL. Statistically significant associations were found between BLL and factors such as maternal age (β=0.01; p=0.02, education (β=0.08; p=0.04 and prepregnancy BMI (β=0.1; p=0.001. Additionally, BLL increased with increasing cotinine level in saliva (β=0.02; p=0.06 and decreased with the increasing distance from the copper smelter (β=-0.1; p=0.009. Public health interventions, especially in regions with a higher level of exposure to lead, among women with lower SES and among smokers, are still reasonable.

  9. Exposure Evaluation for Benzene, Lead and Noise in Vehicle and Equipment Repair Shops

    Energy Technology Data Exchange (ETDEWEB)

    Sweeney, Lynn C. [Washington State Univ., Pullman, WA (United States)

    2013-04-01

    An exposure assessment was performed at the equipment and vehicle maintenance repair shops operating at the U. S. Department of Energy Hanford site, in Richland, Washington. The maintenance shops repair and maintain vehicles and equipment used in support of the Hanford cleanup mission. There are three general mechanic shops and one auto body repair shop. The mechanics work on heavy equipment used in construction, cranes, commercial motor vehicles, passenger-type vehicles in addition to air compressors, generators, and farm equipment. Services include part fabrication, installation of equipment, repair and maintenance work in the engine compartment, and tire and brake services. Work performed at the auto body shop includes painting and surface preparation which involves applying body filler and sanding. 8-hour time-weighted-average samples were collected for benzene and noise exposure and task-based samples were collected for lead dust work activities involving painted metal surfaces. Benzene samples were obtained using 3M™ 3520 sampling badges and were analyzed for additional volatile organic compounds. These compounds were selected based on material safety data sheet information for the aerosol products used by the mechanics for each day of sampling. The compounds included acetone, ethyl ether, toluene, xylene, VM&P naphtha, methyl ethyl ketone, and trichloroethylene. Laboratory data for benzene, VM&P naphtha, methyl ethyl ketone and trichloroethylene were all below the reporting detection limit. Airborne concentrations for acetone, ethyl ether, toluene and xylene were all less than 10% of their occupational exposure limit. The task-based samples obtained for lead dusts were submitted for a metal scan analysis to identify other metals that might be present. Laboratory results for lead dusts were all below the reporting detection limit and airborne concentration for the other metals observed in the samples were less than 10% of the occupational exposure limit

  10. Adolescent pre-exposure prophylaxis for HIV prevention: current perspectives

    Directory of Open Access Journals (Sweden)

    Machado DM

    2017-11-01

    Full Text Available Daisy Maria Machado,1 Alexandre Machado de Sant’Anna Carvalho,2 Rachel Riera3 1Disciplina de Infectologia Pediátrica, Departamento de Pediatria, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, 2Universidade Federal do Rio de Janeiro, Rio de Janeiro, 3Disciplina de Medicina Baseada em Evidências, Departamento de Medicina, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil Abstract: Adolescents are a critical population that is disproportionately impacted by the HIV epidemic. More than 2 million adolescents between the age group of 10 and 19 years are living with HIV, and millions are at risk of infection. HIV risks are considerably higher among girls, especially in high-prevalence settings such as eastern and southern Africa. In addition to girls, there are other vulnerable adolescent subgroups, such as teenagers, who use intravenous (IV drugs, gay and bisexual boys, transgender youth, male sex workers, and people who fall into more than one of these categories. Pre-exposure prophylaxis (PrEP is a new intervention for people at high risk for acquiring HIV, with an estimated HIV incidence of >3%. Recent data from trials show evidence of the efficacy of PrEP as a powerful HIV prevention tool in high-risk populations, including men who have sex with men, HIV-1-serodiscordant heterosexual couples, and IV drug users. The reported efficacy in those trials of the daily use of oral tenofovir, alone or in combination with emtricitabine, to prevent HIV infection ranged from 44% to 75% and was heavily dependent on adherence. Despite the proven efficacy of PrEP in adult trials, concerns remain about its feasibility in real-life scenarios due to stigma, cost, and limited clinician experience with PrEP delivery. Recent studies are attempting to expand the inquiry into the efficacy of such HIV prophylaxis approaches in adolescent populations, but there are still many gaps in knowledge, and no

  11. Quench propagation in High Temperature Superconducting materials integrated in high current leads

    CERN Document Server

    Milani, D

    2001-01-01

    High temperature superconductors (HTS) have been integrated in the high current leads for the Large Hadron Collider (LHC), under construction at CERN, in order to reduce the heat leak into the liquid helium bath due to the joule effect. The use of the HTS technology in the lower part of the current leads allowed to significantly reduce the heat charge on the cryogenic system. Hybrid current leads have been designed to fulfill the LHC requirements with respect to thermal load; several tests have been performed to study the lead behavior especially during a quench transient. Quench experiments have been performed at CERN on 13 kA prototypes to determine the adequate design and protection. In all the tests it is possible to know the temperature profile of the HTS only with the help of quench simulations that model the thermo-hydraulic processes during quench. The development of a theoretical model for the simulation allows reducing the number of test to perform and to scale the experimental result to other curre...

  12. Bi2212 HTS Tubular Bulk with Conical Shape for Current Lead

    International Nuclear Information System (INIS)

    Tamura, H; Mito, T; Yamada, Y; Watanabe, M; Ohkubo, J; Heller, R

    2006-01-01

    Current leads using HTS material have been developed for application in a large scale superconducting magnet system. Tokai University and NIFS have developed Bi2212 tubular bulk which was prepared by a diffusion process. 8 kA of maximum transport current was achieved by a tubular bulk with a cylindrical shape. The maximum current was estimated to be 2 kA at 50 K for this tubular bulk. A current lead can be designed with this bulk the warm end of the HTS part being at 50 K and the cold end at 4.2 K. Under this condition, the cross section of the cold end of the bulk can be reduced. This type of HTS bulk has a great potential for flexible design since the Bi2212 layer can be reacted on the surface of any shapes of substrate. If a conical shaped HTS bulk was made, it could be an advantage for heat leakage to the cold end. To confirm this effect, we have made two types of conical bulk. The transport current of the specimen exceeds 7 kA at 4.2 K and 4 kA of stable current flow was achieved with a warm end temperature of 50 K

  13. Lead exposure through consumption of big game meat in Quebec, Canada: risk assessment and perception.

    Science.gov (United States)

    Fachehoun, Richard Coovi; Lévesque, Benoit; Dumas, Pierre; St-Louis, Antoine; Dubé, Marjolaine; Ayotte, Pierre

    2015-01-01

    Game meat from animals killed by lead ammunition may expose consumers to lead. We assessed the risk related to lead intake from meat consumption of white-tailed deer and moose killed by lead ammunition and documented the perception of hunters and butchers regarding this potential contamination. Information on cervid meat consumption and risk perception were collected using a mailed self-administrated questionnaire which was addressed to a random sample of Quebec hunters. In parallel, 72 samples of white-tailed deer (n = 35) and moose (n = 37) meats were collected from voluntary hunters and analysed for lead content using inductively coupled plasma-mass spectrometry. A risk assessment for people consuming lead shot game meat was performed using Monte Carlo simulations. Mean lead levels in white-tailed deer and moose killed by lead ammunition were 0.28 and 0.17 mg kg(-1) respectively. Risk assessment based on declared cervid meat consumption revealed that 1.7% of the surveyed hunters would exceed the dose associated with a 1 mmHg increase in systolic blood pressure (SBP). For consumers of moose meat once, twice or three times a week, simulations predicted that 0.5%, 0.9% and 1.5% of adults would be exposed to a dose associated with a 1 mmHg increase in SBP, whereas 0.9%, 1.9% and 3.3% of children would be exposed to a dose associated with 1 point intelligence quotient (IQ) decrease, respectively. For consumers of deer meat once, twice or three times a week, the proportions were 1.6%, 2.9% and 4% for adults and 2.9%, 5.8% and 7.7% for children, respectively. The consumption of meat from cervids killed with lead ammunition may increase lead exposure and its associated health risks. It would be important to inform the population, particularly hunters, about this potential risk and promote the use of lead-free ammunition.

  14. Thermo-mechanical tests on W7-X current lead flanges

    International Nuclear Information System (INIS)

    Dhard, Chandra Prakash; Rummel, Thomas; Zacharias, Daniel; Bykov, Victor; Moennich, Thomas; Buscher, Klaus-Peter

    2013-01-01

    Highlights: • There are significant mechanical loads on the cryostat and radial flanges for W7-X current leads. • These are due to evacuation of W7-X cryostat, cool-down of cold mass, electro-magnetic forces and self weight of leads. • The actual mechanical loads were reduced to simplify the experimental set-up. • The tests were carried out on mock-up flanges test assembly at ambient temperature and at 77 K. • The thermo-mechanical tests on W7-X current lead flanges validate the design and joints of these flanges to the leads. -- Abstract: Fourteen pieces of high temperature superconducting current leads (CL) arranged in seven pairs, will be installed on the outer vessel of Wendelstein 7-X (W7-X) stellarator. In order to support the CL, it is provided with two glass fiber reinforce plastic (GFRP) flanges, namely, the lower cryostat flange (CF) remaining at room temperature and upper radial flange (RF) at about 5 K. Both the flanges i.e. CF and RF experience high mechanical loads with respect to the CL, due to the evacuation of W7-X cryostat, cool-down of cold mass including the CL, electro-magnetic forces due to current and plasma operations and self weight of CL. In order to check the integrity of these flanges for such mechanical loads, thermo-mechanical tests were carried out on these flanges at room temperatures and at liquid nitrogen (LN2) temperatures. The details of test set-up, results and modeling are described in the paper

  15. Radiation cancer, safety standards and current levels of exposure

    International Nuclear Information System (INIS)

    Mole, R.H.

    1976-01-01

    Cancer can be induced by radiation in any tissue where cancer occurs naturally. The observation that antenatal diagnostic radiography causes a small but definite increase in childhood cancer is as good evidence as could be expected in support of the scientific expectation that there would be no threshold of dose for carcinogenesis. A linear relation between radiation dose and frequency of induced cancer is a necessary assumption for a system of radiological protection but is not necessarily a reasonable basis for realistic assessments of cancer risk. Indeed there are radiobiological and epidemiological reasons to the contrary. If the linear hypothesis is accepted then at the present time in the UK the routine practice of medicine is of about 2 orders of magnitude more important in causing cancer than environmental pollution by discharge of radio-activity. The acceptability of radiation safety standards for occupational exposure may be justified by comparison of radiation cancer risks with risks from fatal accidents in the safer industries. The acceptability of the corresponding standards for members of the public seems to require more public discussion of the concept of negligible risk. Emotional reactions to uncontrolled releases of radio-activity are based at least in part on a failure to appreciate the hypothesis of linearity

  16. Development of modular thermostatic vapour-cooled current leads for cryogenic service

    International Nuclear Information System (INIS)

    Blessing, H.; Lebrun, P.

    1983-01-01

    Cryogenic current leads cooled by helium vapour have been developed, built and tested. Their construction, based on standard electrolytic copper braids crimped at the ends, is such as to provide flexible cold terminations and make possible a modular design. The warm terminations combine electrical insulation, leak-tightness and integrated thermostatic valves controlling lead temperature and avoiding thermal run-away or ice build-up. After giving a detailed description of their construction, this report presents results of performance and reliability tests made on prototype units. (orig.)

  17. Association of office and ambulatory blood pressure with blood lead in workers before occupational exposure.

    Science.gov (United States)

    Yang, Wen-Yi; Efremov, Ljupcho; Mujaj, Blerim; Zhang, Zhen-Yu; Wei, Fang-Fei; Huang, Qi-Fang; Thijs, Lutgarde; Vanassche, Thomas; Nawrot, Tim S; Staessen, Jan A

    2018-01-01

    In view of decreasing lead exposure and guidelines endorsing ambulatory above office blood pressure (BP) measurement, we reassessed association of BP with blood lead (BL) in 236 newly employed men (mean age, 28.6 years) without previous lead exposure not treated for hypertension. Office BP was the mean of five auscultatory readings at one visit. Twenty-four-hour BP was recorded at 15- and 30-minute intervals during wakefulness and sleep. BL was determined by inductively coupled plasma mass spectrometry. Systolic/diastolic office BP averaged 120.0/80.7 mm Hg, and the 24-hour, awake, and asleep BP 125.5/73.6, 129.3/77.9, and 117.6/65.0 mm Hg, respectively. The geometric mean of blood lead was 4.5 μg/dL (interquartile range, 2.60-9.15 μg/dL). In multivariable-adjusted analyses, effect sizes associated with BL doubling were 0.79/0.87 mm Hg (P = .11/.043) for office BP and 0.29/-0.25, 0.60/-0.10, and -0.40/-0.43 mm Hg for 24-hour, awake, and asleep BP (P ≥ .33). Neither office nor 24-hour ambulatory hypertension was related to BL (P ≥ .14). A clinically relevant white coat effect (WCE; office minus awake BP, ≥20/≥10 mm Hg) was attributable to exceeding the systolic or diastolic threshold in 1 and 45 workers, respectively. With BL doubling, the systolic/diastolic WCE increased by 0.20/0.97 mm Hg (P = .57/.046). Accounting for the presence of a diastolic WCE, reduced the association size of office diastolic BP with BL to 0.39 mm Hg (95% confidence interval, -0.20 to 1.33; P = .15). In conclusion, a cross-sectional analysis of newly hired workers before lead exposure identified the WCE as confounder of the association between office BP and BL and did not reveal any association between ambulatory BP and BL. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  18. Adolescent pre-exposure prophylaxis for HIV prevention: current perspectives

    Science.gov (United States)

    Machado, Daisy Maria; de Sant’Anna Carvalho, Alexandre Machado; Riera, Rachel

    2017-01-01

    Adolescents are a critical population that is disproportionately impacted by the HIV epidemic. More than 2 million adolescents between the age group of 10 and 19 years are living with HIV, and millions are at risk of infection. HIV risks are considerably higher among girls, especially in high-prevalence settings such as eastern and southern Africa. In addition to girls, there are other vulnerable adolescent subgroups, such as teenagers, who use intravenous (IV) drugs, gay and bisexual boys, transgender youth, male sex workers, and people who fall into more than one of these categories. Pre-exposure prophylaxis (PrEP) is a new intervention for people at high risk for acquiring HIV, with an estimated HIV incidence of >3%. Recent data from trials show evidence of the efficacy of PrEP as a powerful HIV prevention tool in high-risk populations, including men who have sex with men, HIV-1-serodiscordant heterosexual couples, and IV drug users. The reported efficacy in those trials of the daily use of oral tenofovir, alone or in combination with emtricitabine, to prevent HIV infection ranged from 44% to 75% and was heavily dependent on adherence. Despite the proven efficacy of PrEP in adult trials, concerns remain about its feasibility in real-life scenarios due to stigma, cost, and limited clinician experience with PrEP delivery. Recent studies are attempting to expand the inquiry into the efficacy of such HIV prophylaxis approaches in adolescent populations, but there are still many gaps in knowledge, and no country has yet approved it for use with adolescents. The aim of this review was to identify and summarize the evidence from studies on PrEP for adolescents. We have compiled and reviewed published studies focusing on safety, feasibility, adherence to therapeutics, self-perception, and legal issues related to PrEP in people aged between 10 and 24 years. PMID:29238237

  19. Biochemical effects of lead exposure on oxidative stress and antioxidant status of battery manufacturing workers of Western Maharashtra, India.

    Science.gov (United States)

    Ghanwat, Ganesh Haribhau; Patil, Arun Jalindar; Patil, Jyotsna A; Kshirsagar, Mandakini S; Sontakke, Ajit; Ayachit, Ram Krishna

    2016-03-01

    Lead induces oxidative stress and alters the antioxidant status of population exposed to high lead levels, i.e. battery manufacturing workers. The aim of this study was to know the current scenario of blood lead (PbB) levels and their effect on the oxidative stress parameter, i.e. serum lipid peroxide (LP), and antioxidant parameters, such as red blood cell (RBC)-superoxide dismutase (SOD), RBC-catalase (CAT), plasma ceruloplasmin (CP), and serum nitrite, of battery manufacturing workers. Forty-three battery manufacturing workers from Western Maharashtra, India, with ages between 19 and 42 years, were selected as study group and compared with 38 age-matched, healthy male subjects (control group). From both group subjects, 10 mL of blood sample was drawn by puncturing the antecubital vein, and PbB, serum LP, RBC-SOD, RBC-CAT, plasma CP, and serum nitrite were estimated using standard methods. The PbB levels of the battery manufacturing workers were significantly higher (pworkers as compared with the control subjects. Despite modern techniques used to reduce lead exposure in battery manufacturing workers, PbB levels remain high, inducing oxidative stress and altering the antioxidant status of battery manufacturing workers.

  20. Estimated lead (Pb) exposures for a population of urban community gardeners.

    Science.gov (United States)

    Spliethoff, Henry M; Mitchell, Rebecca G; Shayler, Hannah; Marquez-Bravo, Lydia G; Russell-Anelli, Jonathan; Ferenz, Gretchen; McBride, Murray

    2016-08-01

    Urban community gardens provide affordable, locally grown, healthy foods and many other benefits. However, urban garden soils can contain lead (Pb) that may pose risks to human health. To help evaluate these risks, we measured Pb concentrations in soil, vegetables, and chicken eggs from New York City community gardens, and we asked gardeners about vegetable consumption and time spent in the garden. We then estimated Pb intakes deterministically and probabilistically for adult gardeners, children who spend time in the garden, and adult (non-gardener) household members. Most central tendency Pb intakes were below provisional total tolerable intake (PTTI) levels. High contact intakes generally exceeded PTTIs. Probabilistic estimates showed approximately 40 % of children and 10 % of gardeners exceeding PTTIs. Children's exposure came primarily from dust ingestion and exposure to higher Pb soil between beds. Gardeners' Pb intakes were comparable to children's (in µg/day) but were dominated by vegetable consumption. Adult household members ate less garden-grown produce than gardeners and had the lowest Pb intakes. Our results suggest that healthy gardening practices to reduce Pb exposure in urban community gardens should focus on encouraging cultivation of lower Pb vegetables (i.e., fruits) for adult gardeners and on covering higher Pb non-bed soils accessible to young children. However, the common practice of replacement of root-zone bed soil with clean soil (e.g., in raised beds) has many benefits and should also continue to be encouraged.

  1. Association between lead exposure from electronic waste recycling and child temperament alterations.

    Science.gov (United States)

    Liu, Junxiao; Xu, Xijin; Wu, Kusheng; Piao, Zhongxian; Huang, Jinrong; Guo, Yongyong; Li, Weiqiu; Zhang, Yuling; Chen, Aimin; Huo, Xia

    2011-08-01

    We aimed to evaluate the dose-dependent effects of lead exposure on temperament alterations in children from a primitive e-waste (obsolete electrical and electronic devices) recycling area in Guiyu of China and a control area (Chendian, China). Blood lead levels (BLL) might be correlated with temperament, health, and relevant factors that were evaluated through Parent Temperament Questionnaire (PTQ), physical examination, and residential questionnaires. We collected venipuncture blood samples from 303 children (aged 3-7 years old) between January and February 2008. Child BLL were higher in Guiyu than in Chendian (median 13.2 μg/dL, range 4.0-48.5 μg/dL vs. 8.2 μg/dL, 0-21.3 μg/dL) (Pchildren (all Pchildren with low BLL (BLLchildren by increasing BLL and altering children temperament, although the exposure to other toxicants needs to be examined in future studies. Copyright © 2011 Elsevier Inc. All rights reserved.

  2. Contribution of maternal smoking during pregnancy and lead exposure to early child behavior problems.

    Science.gov (United States)

    Wasserman, G A; Liu, X; Pine, D S; Graziano, J H

    2001-01-01

    Maternal smoking during pregnancy elevates risk for later child behavior problems. Because prior studies considered only Western settings, where smoking co-occurs with social disadvantage, we examined this association in Yugoslavia, a different cultural setting. Mothers enrolled in pregnancy as the low-exposure group in a prospective study of lead exposure were interviewed about health, including smoking history. A total of 199 children were assessed on the Child Behavior Checklist (CBCL) at ages 4, 4 1/2, and 5 years. Average cumulative blood lead (BPb) was determined from serial samples taken biannually since delivery. Longitudinal analyses were derived from 191 children with available data on behavior and covariates. Smoking was unrelated to social adversity. Controlling for age, gender, birthweight, ethnicity, maternal education, and Home Observation for Measurement of the Environment (HOME) Acceptance, smoking was associated with worse scores on almost all subscales; BPb concentration was related to small increases in the Delinquency subscale. Daughters of smokers received significantly higher scores on Somatic Complaints compared to daughters of nonsmokers, consistent with other work relating biological factors and internalizing problems in young girls. Because the present smoking/child behavior associations persist after control for individual and social factors also related to behavior problems, possible biological mediators are considered.

  3. Early Postnatal Lipopolysaccharide Exposure Leads to Enhanced Neurogenesis and Impaired Communicative Functions in Rats.

    Directory of Open Access Journals (Sweden)

    Yi Pang

    Full Text Available Perinatal infection is a well-identified risk factor for a number of neurodevelopmental disorders, including brain white matter injury (WMI and Autism Spectrum Disorders (ASD. The underlying mechanisms by which early life inflammatory events cause aberrant neural, cytoarchitectural, and network organization, remain elusive. This study is aimed to investigate how systemic lipopolysaccharide (LPS-induced neuroinflammation affects microglia phenotypes and early neural developmental events in rats. We show here that LPS exposure at early postnatal day 3 leads to a robust microglia activation which is characterized with mixed microglial proinflammatory (M1 and anti-inflammatory (M2 phenotypes. More specifically, we found that microglial M1 markers iNOS and MHC-II were induced at relatively low levels in a regionally restricted manner, whereas M2 markers CD206 and TGFβ were strongly upregulated in a sub-set of activated microglia in multiple white and gray matter structures. This unique microglial response was associated with a marked decrease in naturally occurring apoptosis, but an increase in cell proliferation in the subventricular zone (SVZ and the dentate gyrus (DG of hippocampus. LPS exposure also leads to a significant increase in oligodendrocyte lineage population without causing discernible hypermyelination. Moreover, LPS-exposed rats exhibited significant impairments in communicative and cognitive functions. These findings suggest a possible role of M2-like microglial activation in abnormal neural development that may underlie ASD-like behavioral impairments.

  4. Chemical form of selenium differentially influences DNA repair pathways following exposure to lead nitrate.

    Science.gov (United States)

    McKelvey, Shauna M; Horgan, Karina A; Murphy, Richard A

    2015-01-01

    Lead, an environmental toxin is known to induce a broad range of physiological and biochemical dysfunctions in humans through a number of mechanisms including the deactivation of antioxidants thus leading to generation of reactive oxygen species (ROS) and subsequent DNA damage. Selenium on the other hand has been proven to play an important role in the protection of cells from free radical damage and oxidative stress, though its effects are thought to be form and dose dependent. As the liver is the primary organ required for metabolite detoxification, HepG2 cells were chosen to assess the protective effects of various selenium compounds following exposure to the genotoxic agent lead nitrate. Initially DNA damage was quantified using a comet assay, gene expression patterns associated with DNA damage and signalling were also examined using PCR arrays and the biological pathways which were most significantly affected by selenium were identified. Interestingly, the organic type selenium compounds (selenium yeast and selenomethionine) conferred protection against lead induced DNA damage in HepG2 cells; this is evident by reduction in the quantity of DNA present in the comet tail of cells cultured in their presence with lead. This trend also followed through the gene expression changes noted in DNA damage pathways analysed. These results were in contrast with those of inorganic sodium selenite which promoted lead induced DNA damage evident in both the comet assay results and the gene expression analysis. Over all this study provided valuable insights into the effects which various selenium compounds had on the DNA damage and signalling pathway indicating the potential for using organic forms of selenium such as selenium enriched yeast to protect against DNA damaging agents. Copyright © 2014 Elsevier GmbH. All rights reserved.

  5. Transient current in a quantum dot asymmetrically coupled to metallic leads

    International Nuclear Information System (INIS)

    Goker, A; Friedman, B A; Nordlander, P

    2007-01-01

    The time-dependent non-crossing approximation is used to study the transient current in a single-electron transistor attached asymmetrically to two leads following a sudden change in the energy of the dot level. We show that for asymmetric coupling, sharp features in the density of states of the leads can induce oscillations in the current through the dot. These oscillations persist to much longer timescales than the timescale for charge fluctuations. The amplitude of the oscillations increases as the temperature or source-drain bias across the dot is reduced and saturates for values below the Kondo temperature. We discuss the microscopic origin of these oscillations and comment on the possibility for their experimental detection

  6. Passivation of Flexible YBCO Superconducting Current Lead With Amorphous SiO2 Layer

    Science.gov (United States)

    Johannes, Daniel; Webber, Robert

    2013-01-01

    Adiabatic demagnetization refrigerators (ADR) are operated in space to cool detectors of cosmic radiation to a few 10s of mK. A key element of the ADR is a superconducting magnet operating at about 0.3 K that is continually energized and de-energized in synchronism with a thermal switch, such that a piece of paramagnetic salt is alternately warm in a high magnetic field and cold in zero magnetic field. This causes the salt pill or refrigerant to cool, and it is able to suck heat from an object, e.g., the sensor, to be cooled. Current has to be fed into and out of the magnets from a dissipative power supply at the ambient temperature of the spacecraft. The current leads that link the magnets to the power supply inevitably conduct a significant amount of heat into the colder regions of the supporting cryostat, resulting in the need for larger, heavier, and more powerful supporting refrigerators. The aim of this project was to design and construct high-temperature superconductor (HTS) leads from YBCO (yttrium barium copper oxide) composite conductors to reduce the heat load significantly in the temperature regime below the critical temperature of YBCO. The magnet lead does not have to support current in the event that the YBCO ceases to be superconducting. Cus - tomarily, a normal metal conductor in parallel with the YBCO is a necessary part of the lead structure to allow for this upset condition; however, for this application, the normal metal can be dispensed with. Amorphous silicon dioxide is deposited directly onto the surface of YBCO, which resides on a flexible substrate. The silicon dioxide protects the YBCO from chemically reacting with atmospheric water and carbon dioxide, thus preserving the superconducting properties of the YBCO. The customary protective coating for flexible YBCO conductors is silver or a silver/gold alloy, which conducts heat many orders of magnitude better than SiO2 and so limits the use of such a composite conductor for passing current

  7. 600 A HTc current lead based on BSCCO 2212 rods for LHC magnets

    CERN Document Server

    García-Tabarés, L; Abramian, P; Toral, F; Angurel, L A; Diez, J C; Burriel, R; Natividad, E; Iturbe, R; Etxeandia, J

    2000-01-01

    A 600 A current lead using 2212 BSCCO bulk material is now under construction and will be soon delivered to CERN. Present paper describes the main steps of its design and fabrication, including the two main parts in which it is divided, the superconducting module with the BSCCO rods and the conventional resistive part. An important role in this design was played by previous experimental measurements on subassemblies, which are also described along the paper. (5 refs).

  8. Low flow velocity, fine-screen heat exchangers and vapor-cooled cryogenic current leads

    International Nuclear Information System (INIS)

    Steyert, W.A.; Stone, N.J.

    1978-09-01

    The design, construction, and testing of three compact, low temperature heat exchangers are reported. A method is given for the construction of a small (approximately = 20-cm 3 volume) exchanger that can handle 6 g/s helium flow with low pressure drops (ΔP/P = 10 percent) and adequate heat transfer (N/sub tu/ = 3). The use of screen for simple, vapor-cooled current leads into cryogenic systems is also discussed

  9. Optimization of a Two Stage Pulse Tube Refrigerator for the Integrated Current Lead System

    Science.gov (United States)

    Maekawa, R.; Matsubara, Y.; Okada, A.; Takami, S.; Konno, M.; Tomioka, A.; Imayoshi, T.; Hayashi, H.; Mito, T.

    2008-03-01

    Implementation of a conventional current lead with a pulse tube refrigerator has been validated to be working as an Integrated Current Lead (ICL) system for the Superconducting Magnetic Energy Storage (SMES). Realization of the system is primarily accounted for the flexibility of a pulse tube refrigerator, which does not posses any mechanical piston and/or displacer. As for an ultimate version of the ICL system, a High Temperature Superconducting (HTS) lead links a superconducting coil with a conventional copper lead. To ensure the minimization of heat loads to the superconducting coil, a pulse tube refrigerator has been upgraded to have a second cooling stage. This arrangement reduces not only the heat loads to the superconducting coil but also the operating cost for a SMES system. A prototype two-stage pulse tube refrigerator, series connected arrangement, was designed and fabricated to satisfy the requirements for the ICL system. Operation of the first stage refrigerator is a four-valve mode, while the second stage utilizes a double inlet configuration to ensure its confined geometry. The paper discusses the optimization of second stage cooling to validate the conceptual design

  10. Exposure to lead in water and cysteine non-oxidative metabolism in Pelophylax ridibundus tissues

    International Nuclear Information System (INIS)

    Kaczor, Marta; Sura, Piotr; Bronowicka-Adamska, Patrycja; Wróbel, Maria

    2013-01-01

    Chronic, low-level exposure to metals is an increasing global problem. Lead is an environmentally persistent toxin that causes many lead-related pathologies, directly affects tissues and cellular components or exerts an effect of the generation of reactive oxygen species causing a diminished level of available sulfhydryl antioxidant reserves. Cysteine is one of substrates in the synthesis of glutathione – the most important cellular antioxidant, and it may also undergo non-oxidative desulfuration that produces compounds containing sulfane sulfur atoms. The aim of the experiment was to examine changes of the non-oxidative metabolism of cysteine and the levels of cysteine and glutathione in the kidneys, heart, brain, liver and muscle of Marsh frogs (Pelophylax ridibundus) exposed to 28 mg/L Pb(NO 3 ) 2 for 10 days. The activities of sulfurtransferases, enzymes related to the sulfane sulfur metabolism – 3-mercaptopyruvate sulfurtransfearse, γ-cystathionase and rhodanese – were detected in tissue homogenates. The activity of sulfurtransferases was much higher in the kidneys of frogs exposed to lead in comparison to control frogs, not exposed to lead. The level of sulfane sulfur remained unchanged. Similarly, the total level of cysteine did not change significantly. The total levels of glutathione and the cysteine/cystine and GSH/GSSG ratios were elevated. Thus, it seems that the exposure to lead intensified the metabolism of sulfane sulfur and glutathione synthesis in the kidneys. The results presented in this work not only confirm the participation of GSH in the detoxification of lead ions and/or products appearing in response to their presence, such as reactive oxygen species, but also indicate the involvement of sulfane sulfur and rhodanese in this process (e.g. brain). As long as the expression of enzymatic proteins (rhodanese, MPST and CST) is not examined, no answer will be provided to the question whether changes in their activity are due to differences

  11. Exposure to lead in water and cysteine non-oxidative metabolism in Pelophylax ridibundus tissues

    Energy Technology Data Exchange (ETDEWEB)

    Kaczor, Marta [Jagiellonian University Medical College, Kopernika 7, 31-034 Krakow (Poland); Sura, Piotr [Department of Human Developmental Biology, Jagiellonian University Medical College, Kopernika 7, 31-034 Krakow (Poland); Bronowicka-Adamska, Patrycja [Jagiellonian University Medical College, Kopernika 7, 31-034 Krakow (Poland); Wrobel, Maria, E-mail: mbwrobel@cyf-kr.edu.pl [Jagiellonian University Medical College, Kopernika 7, 31-034 Krakow (Poland)

    2013-02-15

    Chronic, low-level exposure to metals is an increasing global problem. Lead is an environmentally persistent toxin that causes many lead-related pathologies, directly affects tissues and cellular components or exerts an effect of the generation of reactive oxygen species causing a diminished level of available sulfhydryl antioxidant reserves. Cysteine is one of substrates in the synthesis of glutathione - the most important cellular antioxidant, and it may also undergo non-oxidative desulfuration that produces compounds containing sulfane sulfur atoms. The aim of the experiment was to examine changes of the non-oxidative metabolism of cysteine and the levels of cysteine and glutathione in the kidneys, heart, brain, liver and muscle of Marsh frogs (Pelophylax ridibundus) exposed to 28 mg/L Pb(NO{sub 3}){sub 2} for 10 days. The activities of sulfurtransferases, enzymes related to the sulfane sulfur metabolism - 3-mercaptopyruvate sulfurtransfearse, {gamma}-cystathionase and rhodanese - were detected in tissue homogenates. The activity of sulfurtransferases was much higher in the kidneys of frogs exposed to lead in comparison to control frogs, not exposed to lead. The level of sulfane sulfur remained unchanged. Similarly, the total level of cysteine did not change significantly. The total levels of glutathione and the cysteine/cystine and GSH/GSSG ratios were elevated. Thus, it seems that the exposure to lead intensified the metabolism of sulfane sulfur and glutathione synthesis in the kidneys. The results presented in this work not only confirm the participation of GSH in the detoxification of lead ions and/or products appearing in response to their presence, such as reactive oxygen species, but also indicate the involvement of sulfane sulfur and rhodanese in this process (e.g. brain). As long as the expression of enzymatic proteins (rhodanese, MPST and CST) is not examined, no answer will be provided to the question whether changes in their activity are due to

  12. Study of electromagnetic interference on quench detecting system of HTS current leads for EAST

    International Nuclear Information System (INIS)

    Hu, Yanlan; Li, Jiangang; Ji, Zhenshan; Zhu, C.M.; Zhen, L.G.; Xiao, Y.Z.

    2013-01-01

    Highlights: • EAST HTS superconducting magnet system shall be operating in a very noisy environment. • Voltage taps will have a lot of inductive voltage induced on them which makes quench detection very difficult. • The noise comes from the coupling between rapid pulsed poloidal coils, and radiation coupling interference associated with EAST heating systems;. • A series of related electromagnetic compatibility simulation tests have been carried out. • Electromagnetic noises are well restrained by choosing proper anti-interference means. -- Abstract: High temperature superconducting (HTS) material B-2223/Ag-Au has been used for EAST poloidal field (PF) coil current leads for reducing construction and operation cost of cryogenic system. The quench propagation velocity of HTS superconducting material is several orders of magnitude lower than that of normal low temperature current leads. It is difficult to detect weak signal of quench which is easily influenced by strong electromagnetic interference (EMI). In this paper, the sources of EMI from quench detecting system of high temperature current leads have been introduced. And we have chosen reasonable methods for good transformation and protection on the basis of electromagnetic compatibility simulation diagnosis experiments. Recent experimental results showed that the restraint of EMI has been achieved and has met the requirements of experiment

  13. Combined exposure of Japanese quails to cyanotoxins, Newcastle virus and lead: oxidative stress responses.

    Science.gov (United States)

    Paskova, Veronika; Veronika, Paskova; Paskerova, Hana; Hana, Paskerova; Pikula, Jiri; Jiri, Pikula; Bandouchova, Hana; Hana, Bandouchova; Sedlackova, Jana; Jana, Sedlackova; Hilscherova, Klara; Klara, Hilscherova

    2011-10-01

    Wild birds are continually exposed to many anthropogenic and natural stressors in their habitats. Over the last decades, mass mortalities of wild birds constitute a serious problem and may possibly have more causations such as natural toxins including cyanotoxins, parasitic diseases, industrial chemicals and other anthropogenic contaminants. This study brings new knowledge on the effects of controlled exposure to multiple stressors in birds. The aim was to test the hypothesis that influence of cyanobacterial biomass, lead and antigenic load may combine to enhance the effects on birds, including modulation of antioxidative and detoxification responses. Eight treatment groups of model species Japanese quail (Coturnix coturnix japonica) were exposed to various combinations of these stressors. The parameters of detoxification and oxidative stress were studied in liver and heart after 30 days of exposure. The antioxidative enzymatic defense in birds seems to be activated quite efficiently, which was documented by the elevated levels and activities of antioxidative and detoxification compounds and by the low incidence of damage to lipid membranes. The greatest modulations of glutathione level and activities of glutathione-S-transferase, glutathione peroxidase, glutathione reductase, superoxide dismutase, catalase and lipid peroxidation were shown mostly in the groups with combined multiple exposures. The results indicate that the antioxidative system plays an important role in the protective response of the tissues to applied stressors and that its greater induction helps to protect the birds from more serious damage. Most significant changes of these "defense" parameters in case of multiple stressors suggest activation of this universal mechanism in situation with complex exposure and its crucial role in protection of the bird health in the environment. Copyright © 2011 Elsevier Inc. All rights reserved.

  14. Foliar or root exposures to smelter particles: Consequences for lead compartmentalization and speciation in plant leaves

    International Nuclear Information System (INIS)

    Schreck, Eva; Dappe, Vincent; Sarret, Géraldine; Sobanska, Sophie; Nowak, Dorota; Nowak, Jakub; Stefaniak, Elżbieta Anna; Magnin, Valérie; Ranieri, Vincent; Dumat, Camille

    2014-01-01

    In urban areas with high fallout of airborne particles, metal uptake by plants mainly occurs by foliar pathways and can strongly impact crop quality. However, there is a lack of knowledge on metal localization and speciation in plants after pollution exposure, especially in the case of foliar uptake. In this study, two contrasting crops, lettuce (Lactuca sativa L.) and rye-grass (Lolium perenne L.), were exposed to Pb-rich particles emitted by a Pb-recycling factory via either atmospheric or soil application. Pb accumulation in plant leaves was observed for both ways of exposure. The mechanisms involved in Pb uptake were investigated using a combination of microscopic and spectroscopic techniques (electron microscopy, laser ablation, Raman microspectroscopy, and X-ray absorption spectroscopy). The results show that Pb localization and speciation are strongly influenced by the type of exposure (root or shoot pathway) and the plant species. Foliar exposure is the main pathway of uptake, involving the highest concentrations in plant tissues. Under atmospheric fallouts, Pb-rich particles were strongly adsorbed on the leaf surface of both plant species. In lettuce, stomata contained Pb-rich particles in their apertures, with some deformations of guard cells. In addition to PbO and PbSO 4 , chemical forms that were also observed in pristine particles, new species were identified: organic compounds (minimum 20%) and hexagonal platy crystals of PbCO 3 . In rye-grass, the changes in Pb speciation were even more egregious: Pb–cell wall and Pb–organic acid complexes were the major species observed. For root exposure, identified here as a minor pathway of Pb transfer compared to foliar uptake, another secondary species, pyromorphite, was identified in rye-grass leaves. Finally, combining bulk and spatially resolved spectroscopic techniques permitted both the overall speciation and the minor but possibly highly reactive lead species to be determined in order to better

  15. Foliar or root exposures to smelter particles: Consequences for lead compartmentalization and speciation in plant leaves

    Energy Technology Data Exchange (ETDEWEB)

    Schreck, Eva [Université de Toulouse, INP, UPS, EcoLab (Laboratoire Ecologie Fonctionnelle et Environnement), ENSAT, Avenue de l' Agrobiopole, 31326 Castanet-Tolosan (France); CNRS, EcoLab, 31326 Castanet-Tolosan (France); Géosciences Environnement Toulouse (GET), Observatoire Midi Pyrénées, Université de Toulouse, CNRS, IRD, 14 Avenue E. Belin, F-31400 Toulouse (France); Dappe, Vincent [LASIR (UMR CNRS 8516), Université de Lille 1, Bât. C5, 59655 Villeneuve d' Ascq Cedex (France); Sarret, Géraldine [ISTerre, UMR 5275, Université Grenoble I, CNRS, F-38041 Grenoble (France); Sobanska, Sophie [LASIR (UMR CNRS 8516), Université de Lille 1, Bât. C5, 59655 Villeneuve d' Ascq Cedex (France); Nowak, Dorota; Nowak, Jakub; Stefaniak, Elżbieta Anna [Department of Chemistry, John Paul II Catholic University of Lublin, Al. Kraśnicka 102, 20-718 Lublin (Poland); Magnin, Valérie [ISTerre, UMR 5275, Université Grenoble I, CNRS, F-38041 Grenoble (France); Ranieri, Vincent [CEA-INAC, 17 rue des Martyrs, 38054 Grenoble Cedex 9 (France); Dumat, Camille, E-mail: camille.dumat@ensat.fr [Université de Toulouse, INP, UPS, EcoLab (Laboratoire Ecologie Fonctionnelle et Environnement), ENSAT, Avenue de l' Agrobiopole, 31326 Castanet-Tolosan (France); CNRS, EcoLab, 31326 Castanet-Tolosan (France)

    2014-04-01

    In urban areas with high fallout of airborne particles, metal uptake by plants mainly occurs by foliar pathways and can strongly impact crop quality. However, there is a lack of knowledge on metal localization and speciation in plants after pollution exposure, especially in the case of foliar uptake. In this study, two contrasting crops, lettuce (Lactuca sativa L.) and rye-grass (Lolium perenne L.), were exposed to Pb-rich particles emitted by a Pb-recycling factory via either atmospheric or soil application. Pb accumulation in plant leaves was observed for both ways of exposure. The mechanisms involved in Pb uptake were investigated using a combination of microscopic and spectroscopic techniques (electron microscopy, laser ablation, Raman microspectroscopy, and X-ray absorption spectroscopy). The results show that Pb localization and speciation are strongly influenced by the type of exposure (root or shoot pathway) and the plant species. Foliar exposure is the main pathway of uptake, involving the highest concentrations in plant tissues. Under atmospheric fallouts, Pb-rich particles were strongly adsorbed on the leaf surface of both plant species. In lettuce, stomata contained Pb-rich particles in their apertures, with some deformations of guard cells. In addition to PbO and PbSO{sub 4}, chemical forms that were also observed in pristine particles, new species were identified: organic compounds (minimum 20%) and hexagonal platy crystals of PbCO{sub 3}. In rye-grass, the changes in Pb speciation were even more egregious: Pb–cell wall and Pb–organic acid complexes were the major species observed. For root exposure, identified here as a minor pathway of Pb transfer compared to foliar uptake, another secondary species, pyromorphite, was identified in rye-grass leaves. Finally, combining bulk and spatially resolved spectroscopic techniques permitted both the overall speciation and the minor but possibly highly reactive lead species to be determined in order to

  16. Dose-Response Relationship between Cumulative Occupational Lead Exposure and the Associated Health Damages: A 20-Year Cohort Study of a Smelter in China.

    Science.gov (United States)

    Wu, Yue; Gu, Jun-Ming; Huang, Yun; Duan, Yan-Ying; Huang, Rui-Xue; Hu, Jian-An

    2016-03-16

    Long-term airborne lead exposure, even below official occupational limits, has been found to cause lead poisoning at higher frequencies than expected, which suggests that China's existing occupational exposure limits should be reexamined. A retrospective cohort study was conducted on 1832 smelting workers from 1988 to 2008 in China. These were individuals who entered the plant and came into continuous contact with lead at work for longer than 3 months. The dose-response relationship between occupational cumulative lead exposure and lead poisoning, abnormal blood lead, urinary lead and erythrocyte zinc protoporphyrin (ZPP) were analyzed and the benchmark dose lower bound confidence limits (BMDLs) were calculated. Statistically significant positive correlations were found between cumulative lead dust and lead fumes exposures and workplace seniority, blood lead, urinary lead and ZPP values. A dose-response relationship was observed between cumulative lead dust or lead fumes exposure and lead poisoning (p lead dust and fumes doses were 0.68 mg-year/m³ and 0.30 mg-year/m³ for lead poisoning, respectively. The BMDLs of workplace airborne lead concentrations associated with lead poisoning were 0.02 mg/m³ and 0.01 mg/m³ for occupational exposure lead dust and lead fume, respectively. In conclusion, BMDLs for airborne lead were lower than occupational exposure limits, suggesting that the occupational lead exposure limits need re-examination and adjustment. Occupational cumulative exposure limits (OCELs) should be established to better prevent occupational lead poisoning.

  17. Mental Health Nurse's Exposure to Workplace Violence Leads to Job Stress, Which Leads to Reduced Professional Quality of Life.

    Science.gov (United States)

    Itzhaki, Michal; Bluvstein, Irit; Peles Bortz, Anat; Kostistky, Hava; Bar Noy, Dor; Filshtinsky, Vivian; Theilla, Miriam

    2018-01-01

    Professional quality of life (ProQOL) reflects how individuals feel about their work as helpers. Psychiatric ward nurses cope with significant psychological and physical challenges, including exposure to verbal and physical violence. This study was based on two aspects of ProQOL, the positive compassion satisfaction, and the negative compassion fatigue, with the aim of investigating the relation of ProQOL to job stress and violence exposure at a large mental health center. Data were collected from 114 mental health nurses (49/63 M/F) who completed a self-administered questionnaire examining violence exposure, ProQOL, and job stress. The results showed that during the last year, almost all nurses (88.6%) experienced verbal violence, and more than half (56.1%) experienced physical violence. Only 2.6% experienced no violence. ProQOL was not associated with violence exposure but was reduced by work stress and by previous exposure to violence; nurses who perceived their work as more stressful had lower satisfaction from their work. In conclusion, although most mental health nurses are exposed to physical and verbal violence, their ProQOL is more related to job stress than to workplace violence (WPV). Hospital managements should conduct work stress reduction intervention programs and promote strategizes to reduce WPV. Further exploration of (a) factors affecting ProQOL and (b) the effect of violence coping workshops on ProQOL is warranted.

  18. Lactational Lead Exposure Perturbates Androgenesis in Juvenile and Pubertal Wistar Rats

    Directory of Open Access Journals (Sweden)

    Odukoya SOA

    2017-10-01

    Full Text Available Background: High to low lead (Pb concentrations in breast milk has been found to perturb some biological events in the postnatal life. While postnatal Pb exposure has been reported to impair some andrological parameters in mammals, the age-dependent andrological signature of lactational Pb poisoning is not clear. Aims and Objectives: This study investigated the effects of Pb exposure during lactational period on the testicular andrological profiles of rats at certain postlactational ages using varying doses of Pb. Material and Methods: Lactating mothers and their pups were randomly divided into 4 groups comprising 24 pups each. The treatment groups received 10mg/dL, 30mg/dL, and 70mg/dLof lead acetate in their drinking water from postnatal day one (P1 to P21 of the lactational period. The control rats received distilled water. At P22, P60, P90 and P120, the pups from each group were euthanized, testes were collected, homogenized and the supernatant was used to assay for testosterone and oestrogen using standard methods. Results: Lactational lead poisoning was associated with depressed testicular testosterone productions (P<0.05 compared with controls and abnormally high levels of testicular oestrogen. These statistically significant differences (P<0.05 in androgens levels were corrected to near normal with increasing postnatal ages at low doses. Conclusion: These results show that lactational Pb intoxication causes reversible androgenic perturbations at low doses but irreversible damage at high doses during postnatal life. Conclusively, high lactational Pb is associated with post-lactational irreversible impairment of androgenic profiles.

  19. Lead exposure from soil in Peruvian mining towns: a national assessment supported by two contrasting examples.

    Science.gov (United States)

    van Geen, Alexander; Bravo, Carolina; Gil, Vladimir; Sherpa, Shaky; Jack, Darby

    2012-12-01

    To estimate the population of Peru living in the vicinity of active or former mining operations that could be exposed to lead from contaminated soil. Geographic coordinates were compiled for 113 active mines, 138 ore processing plants and 3 smelters, as well as 7743 former mining sites. The population living within 5 km of these sites was calculated from census data for 2000. In addition, the lead content of soil in the historic mining town of Cerro de Pasco and around a recent mine and ore processing plant near the city of Huaral was mapped in 2009 using a hand-held X-ray fluorescence analyser. Spatial analysis indicated that 1.6 million people in Peru could be living within 5 km of an active or former mining operation. Two thirds of the population potentially exposed was accounted for by 29 clusters of mining operations, each with a population of over 10 000 each. These clusters included 112 active and 3438 former mining operations. Soil lead levels exceeded 1200 mg/kg, a reference standard for residential soil, in 35 of 74 sites tested in Cerro de Pasco but in only 4 of 47 sites tested around the newer operations near Huaral. Soil contamination with lead is likely to be extensive in Peruvian mining towns but the level of contamination is spatially far from uniform. Childhood exposure by soil ingestion could be substantially reduced by mapping soil lead levels, making this information public and encouraging local communities to isolate contaminated areas from children.

  20. Transient current in a quantum dot subject to a change in coupling to its leads

    International Nuclear Information System (INIS)

    Izmaylov, A F; Goker, A; Friedman, B A; Nordlander, P

    2006-01-01

    The time-dependent non-crossing approximation is used to calculate the transient currents through a quantum dot in the Kondo regime subject to a sudden change in its coupling to the leads. The currents are found to display transient non-universal behaviour immediately after the perturbation and then to follow a slow universal increase toward equilibrium. The timescales for the approach to equilibrium are shown to be the same as those recently identified in a study of transient currents in a quantum dot subject to a sudden change in the energy of the dot level (Plihal et al 2005 Phys. Rev. B 71 165321). We present improved numerical algorithms which enable relatively fast calculation of the transient response of quantum dots to sudden perturbations

  1. Could persistency of current of injury forecast successful active-fixation pacing lead implantation?

    Science.gov (United States)

    Shali, Shalaimaiti; Su, Yangang; Qin, Shengmei; Ge, Junbo

    2018-05-01

    Presence of adequate current of injury (COI) was recognized as a sign of favorable pacemaker lead outcome. Little is known regarding the value of its dynamic behavior. We sought to test whether persistency of COI could predict active-fixation pacing lead performance. COI was monitored up to 10min after right ventricular (RV) pacing electrode fixation. COI persistency was defined as the percentage of COI magnitude relative to its initial measurement. An unacceptable pacing threshold (≥1.0V in acute evaluation or ≥2.0V over 2-year follow-up) with or without lead dislodgement was considered as lead failure. Lead implantation was attempted for 217 times in 174 patients (age 66.3±7.8years, 78 female). Acute lead failures occurred 43 times. Independent predictors of acute lead failure were RV enlargement (odds ratio [OR] 1.23, 95% confidential interval [CI] 1.11-2.04, P=0.033), absence of COI (OR 3.13, 95%CI 2.08-9.09, P=0.027), and COI persistency at 5min (OR 0.32, 95%CI 0.20-0.69, P=0.001) and 10min (OR 0.41, 95%CI 0.13-0.77, P=0.001). The optimal cutoffs were COI 5min persistency ≥50% (sensitivity 81.4%; specificity 81.9%) and COI 10min persistency ≥20% (sensitivity 86%; specificity 88.6%). There were 12 lead failures during 24.0±6.4months of follow-up. Patients with COI 5min persistency ≥50% had higher event-free survival compared to those with COI 5min persistency <50% (hazard ratio 3.54, 95% CI 1.04-12.06, P=0.043). COI persistency appears to be a valuable indicator for both acute and long-term outcome of active-fixation pacemaker leads. A precipitous decline in COI may require more attention to make sure of the lead performance. Copyright © 2018 Elsevier Ireland Ltd. All rights reserved.

  2. Lead exposure in children living in a smelter community in region Lagunera, Mexico.

    Science.gov (United States)

    García Vargas, G G; Rubio Andrade, M; Del Razo, L M; Borja Aburto, V; Vera Aguilar, E; Cebrián, M E

    2001-03-23

    Industrial growth has created the potential for environmental problems in Mexico, since attention to environmental controls and urban planning has lagged behind the pace of industrialization. The aim of this cross-sectional study was to assess lead exposure in children aged 6-9 yr attending 3 primary schools and living in the vicinity of the largest smelter complex in Mexico. One of the schools is located 650 m distant from a smelter complex that includes a lead smelter (close school); the second is located 1750 m away from the complex and at the side of a heavy traffic road (intermediate school) in Torreon, Coahuila. The third school is located in Comez Palacio, Durango, 8100 m away from the smelter complex and distant from heavy vehicular traffic or industrial areas (remote school). Lead was measured in air, soil, dust, and well water. Lead in blood (PbB) was determined in 394 children attending the above mentioned schools. Determinations were performed by atomic absorption spectrometry. Diet, socioeconomic status, hygienic habits, and other variables were assessed by questionnaire. Median (range) PbB values were 7.8 microg/dl (3.54-29.61) in the remote school, 21.8 microg/dl (8.37-52.08) in the intermediate school and 27.6 microg/dl (7.37-58.53) in children attending the close school. The percentage of children with PbB > 15 microg/dl was 6.80%, 84.9%, and 92.1% respectively. In this order, the geometric means (range) of Pb concentrations in air were 2.5 microg/m3 (1.1-7.5), 5.8 microg/m3 (4.3-8.5), and 6.1 microg/m3 (1.6-14.9). The Pb concentrations in dust from playgrounds areas in the intermediate and close school settings ranged from 1,457 to 4,162.5 mg/kg. Pb concentrations in drinking water were less than 5 microg/L. Soil and dust ingestion and inhalation appear to be the main routes of exposure. Our results indicate that environmental contamination has resulted in an increased body burden of Pb, suggesting that children living in the vicinity of the

  3. Subacute effects of low dose lead nitrate and mercury chloride exposure on kidney of rats.

    Science.gov (United States)

    Apaydın, Fatma Gökçe; Baş, Hatice; Kalender, Suna; Kalender, Yusuf

    2016-01-01

    Lead nitrate and mercury chloride are the most common heavy metal pollutants. In the present study, the effects of lead and mercury induced nephrotoxicity were studied in Wistar rats. Lead nitrate (LN, 45 mg/kg b.w/day) and mercury chloride (MC, 0.02 mg/kg b.w/day) and their combination were administered orally for 28 days. Four groups of rats were used in the study: control, LN, MC and LN plus MC groups. Serum biochemical parameters, lipid peroxidation, antioxidant enzymes and histopathological changes in kidney tissues were investigated in all treatment groups. LN and MC caused severe histopathological changes. It was shown that LN, MC and also co-treatment with LN and MC exposure induced significant increase in serum urea, uric acid and creatinine levels. There were also statistically significant changes in antioxidant enzyme activities (SOD, CAT, GPx and GST) and lipid peroxidation (MDA) in all groups except control group. In this study, we showed that MC caused more harmful effects than LN in rats. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. Blood morphology and the levels of selected cytokines related to hematopoiesis in occupational short-term exposure to lead

    Energy Technology Data Exchange (ETDEWEB)

    Dobrakowski, Michał, E-mail: michal.dobrakowski@poczta.fm [Department of Biochemistry, School of Medicine with the Division of Dentistry, Medical University of Silesia, ul. Jordana 19, 41-808 Zabrze (Poland); Boroń, Marta [Institute of Occupational Medicine and Environmental Health in Sosnowiec, ul. Kościelna 13, 41-200 Sosnowiec (Poland); Czuba, Zenon P. [Department of Microbiology and Immunology, School of Medicine with the Division of Dentistry, Medical University of Silesia, ul. Jordana 19, 41-808 Zabrze (Poland); Birkner, Ewa [Department of Biochemistry, School of Medicine with the Division of Dentistry, Medical University of Silesia, ul. Jordana 19, 41-808 Zabrze (Poland); Chwalba, Artur [SP ZOZ Municipal Hospital, Department of Internal Medicine, ul. Strzelców Bytomskich 11, 41-500 Chorzów (Poland); Hudziec, Edyta; Kasperczyk, Sławomir [Department of Biochemistry, School of Medicine with the Division of Dentistry, Medical University of Silesia, ul. Jordana 19, 41-808 Zabrze (Poland)

    2016-08-15

    The aim of the study was to investigate the influence of a short-term exposure to lead on the blood morphology and the levels of selected cytokines related to hematopoiesis in occupationally exposed workers. The study population included 37 males occupationally exposed to lead for 36 to 44 days. Their blood lead level raised from 10.7 ± 7.67 μg/dl at baseline to the level of 49.1 ± 14.1 μg/dl at the end of the study. The level of hemoglobin and values of MCH and MCHC were decreased due to a short-term exposure to lead by 2%, 2%, and 1%, respectively. The counts of WBC, LYM, and MXD increased significantly by 5%, 7%, and 35%. Similarly, the count of PLT increased by 7%, while PDW, MPV, and P-LCR decreased by 6%, 3%, and 9%, respectively. The levels of IL-7, G-CSF, HGF, PDGF AB/BB, SCF, and PECAM-1, decreased significantly by 30%, 33%, 8%, 30%, 25%, and 20%, respectively. A short-term occupational exposure to lead results in a decreased hemoglobin level and increased counts of WBC and PLT. Changes in counts and proportions of different types of leukocytes and decreased values of PLT indices, such as PDW, MPV, and P-LCR, due to the subacute lead-exposure may be associated with lead-induced decreased levels of cytokines related to hematopoiesis, including SCF, G-CSF, IL-7, and PDGF. - Highlights: • Subacute exposure to lead results in a decreased hemoglobin level. • Subacute exposure to lead results in increased counts of WBC and PLT. • Subacute exposure to lead decreases the levels of SCF, G-CSF, IL-7, and PDGF.

  5. Blood morphology and the levels of selected cytokines related to hematopoiesis in occupational short-term exposure to lead

    International Nuclear Information System (INIS)

    Dobrakowski, Michał; Boroń, Marta; Czuba, Zenon P.; Birkner, Ewa; Chwalba, Artur; Hudziec, Edyta; Kasperczyk, Sławomir

    2016-01-01

    The aim of the study was to investigate the influence of a short-term exposure to lead on the blood morphology and the levels of selected cytokines related to hematopoiesis in occupationally exposed workers. The study population included 37 males occupationally exposed to lead for 36 to 44 days. Their blood lead level raised from 10.7 ± 7.67 μg/dl at baseline to the level of 49.1 ± 14.1 μg/dl at the end of the study. The level of hemoglobin and values of MCH and MCHC were decreased due to a short-term exposure to lead by 2%, 2%, and 1%, respectively. The counts of WBC, LYM, and MXD increased significantly by 5%, 7%, and 35%. Similarly, the count of PLT increased by 7%, while PDW, MPV, and P-LCR decreased by 6%, 3%, and 9%, respectively. The levels of IL-7, G-CSF, HGF, PDGF AB/BB, SCF, and PECAM-1, decreased significantly by 30%, 33%, 8%, 30%, 25%, and 20%, respectively. A short-term occupational exposure to lead results in a decreased hemoglobin level and increased counts of WBC and PLT. Changes in counts and proportions of different types of leukocytes and decreased values of PLT indices, such as PDW, MPV, and P-LCR, due to the subacute lead-exposure may be associated with lead-induced decreased levels of cytokines related to hematopoiesis, including SCF, G-CSF, IL-7, and PDGF. - Highlights: • Subacute exposure to lead results in a decreased hemoglobin level. • Subacute exposure to lead results in increased counts of WBC and PLT. • Subacute exposure to lead decreases the levels of SCF, G-CSF, IL-7, and PDGF.

  6. Case-only gene-environment interaction between ALAD tagSNPs and occupational lead exposure in prostate cancer.

    Science.gov (United States)

    Neslund-Dudas, Christine; Levin, Albert M; Rundle, Andrew; Beebe-Dimmer, Jennifer; Bock, Cathryn H; Nock, Nora L; Jankowski, Michelle; Datta, Indrani; Krajenta, Richard; Dou, Q Ping; Mitra, Bharati; Tang, Deliang; Rybicki, Benjamin A

    2014-05-01

    Black men have historically had higher blood lead levels than white men in the U.S. and have the highest incidence of prostate cancer in the world. Inorganic lead has been classified as a probable human carcinogen. Lead (Pb) inhibits delta-aminolevulinic acid dehydratase (ALAD), a gene recently implicated in other genitourinary cancers. The ALAD enzyme is involved in the second step of heme biosynthesis and is an endogenous inhibitor of the 26S proteasome, a master system for protein degradation and a current target of cancer therapy. Using a case-only study design, we assessed potential gene-environment (G × E) interactions between lifetime occupational Pb exposure and 11 tagSNPs within ALAD in black (N = 260) and white (N = 343) prostate cancer cases. Two ALAD tagSNPs in high linkage disequilibrium showed significant interaction with high Pb exposure among black cases (rs818684 interaction odds ratio or IOR = 2.73, 95% CI 1.43-5.22, P = 0.002; rs818689 IOR = 2.20, 95% CI 1.15-4.21, P = 0.017) and an additional tagSNP, rs2761016, showed G × E interaction with low Pb exposure (IOR = 2.08, 95% CI 1.13-3.84, P = 0.019). Further, the variant allele of rs818684 was associated with a higher Gleason grade in those with high Pb exposure among both blacks (OR 3.96, 95% CI 1.01-15.46, P = 0.048) and whites (OR 2.95, 95% CI 1.18-7.39, P = 0.020). Genetic variation in ALAD may modify associations between Pb and prostate cancer. Additional studies of ALAD, Pb, and prostate cancer are warranted and should include black men. Prostate 74:637-646, 2014. © 2014 Wiley Periodicals, Inc. © 2014 Wiley Periodicals, Inc.

  7. Perinatal exposure to lead (Pb) induces ultrastructural and molecular alterations in synapses of rat offspring.

    Science.gov (United States)

    Gąssowska, Magdalena; Baranowska-Bosiacka, Irena; Moczydłowska, Joanna; Frontczak-Baniewicz, Małgorzata; Gewartowska, Magdalena; Strużyńska, Lidia; Gutowska, Izabela; Chlubek, Dariusz; Adamczyk, Agata

    2016-12-12

    Lead (Pb), environmentally abundant heavy-metal pollutant, is a strong toxicant for the developing central nervous system. Pb intoxication in children, even at low doses, is found to affect learning and memorizing, with devastating effects on cognitive function and intellectual development. However, the precise mechanism by which Pb impairs synaptic plasticity is not fully elucidated. The purpose of this study was to investigate the effect of pre- and neonatal exposure to low dose of Pb (with Pb concentrations in whole blood below 10μg/dL) on the synaptic structure and the pre- and postsynaptic proteins expression in the developing rat brain. Furthermore, the level of brain-derived neurotrophic factor (BDNF) was analyzed. Pregnant female Wistar rats received 0.1% lead acetate (PbAc) in drinking water from the first day of gestation until weaning of the offspring, while the control animals received drinking water. During the feeding of pups, mothers from the Pb-group were continuously receiving PbAc. Pups of both groups were weaned at postnatal day 21 and then until postnatal day 28 received only drinking water. 28-day old pups were sacrificed and the ultrastructural changes as well as expression of presynaptic (VAMP1/2, synaptophysin, synaptotagmin-1, SNAP25, syntaxin-1) and postsynaptic (PSD-95) proteins were analyzed in: forebrain cortex, cerebellum and hippocampus. Our data revealed that pre- and neonatal exposure to low dose of Pb promotes pathological changes in synapses, including nerve endings swelling, blurred and thickened synaptic cleft structure as well as enhanced density of synaptic vesicles in the presynaptic area. Moreover, synaptic mitochondria were elongated, swollen or shrunken in Pb-treated animals. These structural abnormalities were accompanied by decrease in the level of key synaptic proteins: synaptotagmin-1 in cerebellum, SNAP25 in hippocampus and syntaxin-1 in cerebellum and hippocampus. In turn, increased level of synaptophysin was

  8. Reduction of in utero lead exposures in South African populations: Positive impact of unleaded petrol.

    Directory of Open Access Journals (Sweden)

    Halina B Röllin

    Full Text Available Prenatal exposure to lead (Pb has been shown to have negative and irreversible health impacts on foetal and early childhood development, affecting morbidity and mortality in adulthood. This study aimed to assess in utero Pb exposure, examine birth outcomes, and identify confounding factors in the large cohort of South African population, following the legislated removal of Pb from petrol.Lead was measured in the maternal blood, urine and cord blood using Inductive Coupled Plasma Mass spectrometry (ICP-MS. The statistical analyses included Spearman's correlation, Wilcoxon rank sum (Mann Whitney, Kruskal-Wallis rank tests and multivariate linear regression.Overall, the geometric mean (GM of Pb in maternal blood (PbB was 1.32 μg/dL (n = 640; 95% CI, 1.24-1.40. In the subset cohort, the GM of paired maternal PbB and cord blood (PbC was 1.73 μg/dL (n = 350; 95% CI, 1.60-1.86 and 1.26 μg/dL (n = 317; 95% CI, 1.18-1.35, respectively with a positive correlation between the log PbB and the log PbC (rho = 0.65, p = <0.001. Birth outcomes showed geographical differences in the gestational age (p<0.001, birth length (p = 0.028 and head circumference (p<0.001, Apgar score at 5 min (p<0.001 and parity (p<0.002. In female neonates, a positive association was found between PbC and head circumference (rho = 0.243; p<0.016. The maternal PbB levels were positively correlated with race, educational status, water sources, cooking fuels and use of pesticides at home.This study has demonstrated not only the positive impact that the introduction of unleaded petrol and lead-free paint has had on in utero exposure to Pb in South Africa, but has also contributed new data on the topic, in a region where such data and scientific investigations in this field are lacking. Future research should evaluate if similar effects can be detected in young children and the adult population.

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

    Energy Technology Data Exchange (ETDEWEB)

    Simões, Maylla Ronacher, E-mail: yllars@hotmail.com [Dept. of Physiological Sciences, Federal University of Espirito Santo, Vitória, ES CEP 29040-091 (Brazil); Department of Pharmacology, Universidad Autonoma de Madrid, Instituto de Investigación Hospital Universitario La Paz (IdiPAZ), Madrid (Spain); Aguado, Andrea [Department of Pharmacology, Universidad Autonoma de Madrid, Instituto de Investigación Hospital Universitario La Paz (IdiPAZ), Madrid (Spain); Fiorim, Jonaína; Silveira, Edna Aparecida; Azevedo, Bruna Fernandes; Toscano, Cindy Medice [Dept. of Physiological Sciences, Federal University of Espirito Santo, Vitória, ES CEP 29040-091 (Brazil); Zhenyukh, Olha; Briones, Ana María [Department of Pharmacology, Universidad Autonoma de Madrid, Instituto de Investigación Hospital Universitario La Paz (IdiPAZ), Madrid (Spain); Alonso, María Jesús [Dept. of Biochemistry, Physiology and Molecular Genetics, Universidad Rey Juan Carlos, Alcorcón (Spain); Vassallo, Dalton Valentim [Dept. of Physiological Sciences, Federal University of Espirito Santo, Vitória, ES CEP 29040-091 (Brazil); Health Science Center of Vitória-EMESCAM, Vitória, ES CEP 29045-402 (Brazil); Salaices, Mercedes, E-mail: mercedes.salaices@uam.es [Department of Pharmacology, Universidad Autonoma de Madrid, Instituto de Investigación Hospital Universitario La Paz (IdiPAZ), Madrid (Spain)

    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

  10. Lead exposure of workers employed as tappers in a platinum smelting environment / Morné de Beer

    OpenAIRE

    De Beer, Morné

    2004-01-01

    The study was undertaken after initial surveys indicated that lead (Pb) was present at concentrations in excess of the occupational exposure limit (OEL) on the matte tapping floor (MTF). A follow up study was designed in accordance with the Occupational Exposure Sampling Strategy Manual (OESSM), to determine personal exposure levels of the tappers to Pb whom are employed on the MTF. Following the initial static samples taken during the identification phase, follow up static ...

  11. Electroplated reticulated vitreous carbon current collectors for lead-acid batteries: opportunities and challenges

    Science.gov (United States)

    Gyenge, Elod; Jung, Joey; Mahato, Basanta

    Reticulated, open-cell structures based on vitreous carbon substrates electroplated with a Pb-Sn (1 wt.%) alloy were investigated as current collectors for lead-acid batteries. Scanning and backscattered electron microscopy, cyclic voltammetry, anodic polarization and flooded 2 V single-cell battery testing was employed to characterize the performance of the proposed collectors. A battery equipped with pasted electroplated reticulated vitreous carbon (RVC) electrodes of 137 cm 2 geometric area, at the time of manuscript submission, completed 500 cycles and over 1500 h of continuous operation. The cycling involved discharges at 63 A kg PAM-1 corresponding to a nominal 0.75 h rate and a positive active mass (PAM) utilization efficiency of 21%. The charging protocol was composed of two voltage limited (i.e. 2.6 V/cell), constant current steps of 35 and 9.5 A kg PAM-1, respectively, with a total duration of about 2 h. The charge factor was 1.05-1.15. The observed cycling behavior in conjunction with the versatility of electrodeposition to produce application-dependent optimized lead alloy coating thickness and composition shows promise for the development of lead-acid batteries using electroplated reticulated vitreous carbon collectors.

  12. Operational Experience and Consolidations for the Current Lead Control Valves of the Large Hadron Collider

    CERN Document Server

    Perin, A; Pirotte, O; Krieger, B; Widmer, A

    2012-01-01

    The Large Hadron Collider superconducting magnets are powered by more than 1400 gas cooled current leads ranging from 120 A to 13000 A. The gas flow required by the leads is controlled by solenoid proportional valves with dimensions from DN 1.8 mm to DN 10 mm. During the first months of operation, signs of premature wear were found in the active parts of the valves. This created major problems for the functioning of the current leads threatening the availability of the LHC. Following the detection of the problems, a series of measures were implemented to keep the LHC running, to launch a development program to solve the premature wear problem and to prepare for a global consolidation of the gas flow control system. This article describes first the difficulties encountered and the measures taken to ensure a continuous operation of the LHC during the first year of operation. The development of new friction free valves is then presented along with the consolidation program and the test equipment developed to val...

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

    Directory of Open Access Journals (Sweden)

    Adela Yalemsew

    2012-07-01

    Full Text Available Abstract 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

  14. Epigenetics of early-life lead exposure and effects on brain development.

    Science.gov (United States)

    Senut, Marie-Claude; Cingolani, Pablo; Sen, Arko; Kruger, Adele; Shaik, Asra; Hirsch, Helmut; Suhr, Steven T; Ruden, Douglas

    2012-12-01

    The epigenetic machinery plays a pivotal role in the control of many of the body's key cellular functions. It modulates an array of pliable mechanisms that are readily and durably modified by intracellular or extracellular factors. In the fast-moving field of neuroepigenetics, it is emerging that faulty epigenetic gene regulation can have dramatic consequences on the developing CNS that can last a lifetime and perhaps even affect future generations. Mounting evidence suggests that environmental factors can impact the developing brain through these epigenetic mechanisms and this report reviews and examines the epigenetic effects of one of the most common neurotoxic pollutants of our environment, which is believed to have no safe level of exposure during human development: lead.

  15. [Prenatal lead exposure related to cord blood brain derived neurotrophic factor (BDNF) levels and impaired neonatal neurobehavioral development].

    Science.gov (United States)

    Ren, L H; Mu, X Y; Chen, H Y; Yang, H L; Qi, W

    2016-06-01

    To explore the relationship between umbilical cord blood brain-derived neurotrophic factor (BDNF) and neonatal neurobehavioral development in lead exposure infants. All infants and their mother were randomly selected during 2011 to 2012, subjects were selected according to the umbilical cord blood lead concentrations, which contcentration of lead was higher than 0.48 μmol/L were taken into high lead exposure group, about 60 subjects included. Comparing to the high lead exposure group, according to gender, weight, pregnant week, length and head circumferenece, the level of cord blood lead concentration under 0.48 μmol/L were taken into control group, 60 cases included. Lead content was determined by graphite furnace atomic absorption spectrometry. Neonatal behavioral neurological assessment (NBNA) was used to determine the development of neonatal neuronal behavior. The content of BDNF was detected by ELISA. Comparing the BDNF and the NBNA score between two groups, and linear correlation was given on analysis the correlation between lead concentration in cord blood and BDNF, BDNF and the NBNA score. Lead content in high exposure group was (0.613±0.139) μmol/L, and higher than (0.336±0.142) μmol/L in low exposure group (t=3.21, PBDNF content in high exposure group which was (3.538±1.203) ng/ml was higher than low exposure group (2.464±0.918) ng/ml (t=7.60, PBDNF content was negatively correlated with NBNA summary score, passive muscle tension and active muscle tone score (r was -0.27, -0.29, -0.30, respectively, P values were BDNF was negatively correlated with neonatal neurodevelopment, may serve as a useful biomarker.

  16. Tissue lead concentration during chronic exposure of Pimephales promelas (fathead minnow) to lead nitrate in aquarium water.

    Science.gov (United States)

    Spokas, Eric G; Spur, Bernd W; Smith, Holly; Kemp, Francis W; Bogden, John D

    2006-11-01

    The fathead minnow is a useful species for evaluating the toxicity of wastewater effluents. While this fish is widely used for "survival" studies of metal toxicity, little or no work has been done on the tissue distribution of metals in fathead minnows. To determine the distribution of tissue lead, aquarium studies were conducted for several weeks with fish maintained in soft synthetic freshwater. Lead- (II) nitrate was added to three aquaria attaining concentrations of 20-30 ppb (aquarium B), 100-140 ppb (aquarium C), and roughly 200 ppb (aquarium D). Results were compared to controls (aquarium A). During the initial week, the majority of aquarium D fish died, whereas few deaths occurred in the other groups. Lead accumulation was dose- and tissue-dependent, with highest uptake by the gills. Gill concentrations of aquarium D fish averaged about 4-fold higherthan in skeleton or skin and muscle. In vitro, lead (2.5-25 ppm) caused dose-dependent reductions in the ratio of reduced glutathione/oxidized glutathione (GSH/GSSG) in gills incubated in physiological buffer. These findings demonstrate that fathead minnow gills bind and accumulate waterborne lead rapidly and preferentially and raise the possibility that gill lipid peroxidation contributes to lead toxicity at low water hardness.

  17. Lead exposure in raptors from Japan and source identification using Pb stable isotope ratios.

    Science.gov (United States)

    Ishii, Chihiro; Nakayama, Shouta M M; Ikenaka, Yoshinori; Nakata, Hokuto; Saito, Keisuke; Watanabe, Yukiko; Mizukawa, Hazuki; Tanabe, Shinsuke; Nomiyama, Kei; Hayashi, Terutake; Ishizuka, Mayumi

    2017-11-01

    Lead (Pb) poisoning is widespread among raptors and water birds. In Japan, fragments of Pb ammunition are still found in endangered eagles although more than 10 years have passed since legislation regarding use of Pb ammunition was introduced. This study was performed to investigate Pb exposure in raptors from various locations in Japan. We measured hepatic and renal Pb concentrations and hepatic Pb isotope ratios of Steller's sea eagles (Haliaeetus pelagicus), white-tailed sea eagles (Haliaeetus albicilla), golden eagles (Aquila chrysaetos), and 13 other species (total 177 individuals) that were found dead, as well as blood samples from three eagles found in a weakened state during 1993-2015 from Hokkaido (northern part), Honshu (the main island), and Shikoku (a southern island) of Japan. In the present study in Hokkaido, one quarter of the sea eagles showed a high Pb concentration, suggesting exposure to abnormally high Pb levels and Pb poisoning. Pb isotope ratios indicated that endangered Steller's sea eagle and white-tailed sea eagle were poisoned by Pb ammunition that was used illegally in Hokkaido. In other areas of Japan, both surveillance and regulations were less extensive than in Hokkaido, but Pb poisoning in raptors was also noted. Therefore, Pb poisoning is still a serious problem in raptors in various areas of Japan due to accidental ingestion of materials containing Pb, especially Pb ammunition. Copyright © 2017. Published by Elsevier Ltd.

  18. The conjoint influence of home enriched environment and lead exposure on children's cognition and behaviour in a Mexican lead smelter community.

    Science.gov (United States)

    Moodie, Sue; Ialongo, Nick; López, Patricia; Rosado, Jorge; García-Vargas, Gonzalo; Ronquillo, Dolores; Kordas, Katarzyna

    2013-01-01

    A range of studies has been conducted on the detrimental effects of lead in mining and smelting communities. The neurocognitive and behavioural health effects of lead on children are well known. This research characterized the conjoint influence of lead exposure and home enriched environment on neurocognitive function and behaviour for first-grade children living in a Mexican lead smelter community. Structural equation models were used for this analysis with latent outcome variables, Cognition and Behaviour, constructed based on a battery of assessments administered to the first-grade children, their parents, and teachers. Structural equation modelling was used to describe complex relationships of exposure and health outcomes in a manner that permitted partition of both direct and indirect effects of the factors being measured. Home Environment (a latent variable constructed from information on mother's education and support of school work and extracurricular activities), and child blood lead concentration each had a main significant effect on cognition and behaviour. However, there were no statistically significant moderation relationships between lead and Home Environment on these latent outcomes. Home Environment had a significant indirect mediation effect between lead and both Cognition and Behaviour (p-valueEnvironment has a moderate mediation effect with respect to lead effects on Behaviour (β=0.305) and a lower mediation effect on Cognition (β=0.184). The extent of home enrichment in this study was most highly related to the mother's support of schoolwork and slightly less by the mother's support of extracurricular activities or mother's education. Further research may be able to develop approaches to support families to make changes within their home and child rearing practices, or advocate for different approaches to support their child's behaviour to reduce the impact of lead exposure on children's cognitive and behavioural outcomes. Copyright © 2012

  19. Physiological effects of waterborne lead exposure in spiny dogfish (Squalus acanthias).

    Science.gov (United States)

    Eyckmans, Marleen; Lardon, Isabelle; Wood, Chris M; De Boeck, Gudrun

    2013-01-15

    To broaden our knowledge about the toxicity of metals in marine elasmobranchs, cannulated spiny dogfish (Squalus acanthias) were exposed to 20 μM and 100 μM lead (Pb). Since we wanted to focus on sub lethal ion-osmoregulatory and respiratory disturbances, arterial blood samples were analysed for pH(a), PaO(2), haematocrit and total CO(2) values at several time points. Plasma was used to determine urea, TMAO, lactate and ion concentrations. After 96 h, Pb concentrations were determined in a number of tissues, such as gill, rectal gland, skin and liver. To further investigate ion and osmoregulation, Na(+)/K(+)-ATPase activities in gill and rectal gland were analysed as well as rates of ammonia and urea excretion. Additionally, we studied the energy reserves in muscle and liver. Pb strongly accumulated in gills and especially in skin. Lower accumulation rates occurred in gut, kidney and rectal gland. A clear disturbance in acid-base status was observed after one day of exposure indicating a transient period of hyperventilation. The increase in pH(a) was temporary at 20 μM, but persisted at 100 μM. After 2 days, plasma Na and Cl concentrations were reduced compared to controls at 100 μM Pb and urea excretion rates were elevated. Pb caused impaired Na(+)/K(+)-ATPase activity in gills, but not in rectal gland. We conclude that spiny dogfish experienced relatively low ion-osmoregulatory and respiratory distress when exposed to lead, particularly when compared to effects of other metals such as silver. These elasmobranchs appear to be able to minimize the disturbance and maintain physiological homeostasis during an acute Pb exposure. Copyright © 2012 Elsevier B.V. All rights reserved.

  20. Occupational exposure to anesthetics leads to genomic instability, cytotoxicity and proliferative changes

    International Nuclear Information System (INIS)

    Souza, Kátina M.; Braz, Leandro G.; Nogueira, Flávia R.; Souza, Marajane B.; Bincoleto, Lahis F.; Aun, Aline G.; Corrente, José E.; Carvalho, Lídia R.; Braz, José Reinaldo C.; Braz, Mariana G.

    2016-01-01

    Highlights: • Anesthesiologists exposed to the most commonly used anesthetic gases were evaluated. • No alterations were detected for lymphocyte DNA damage detected by the comet assay. • Decreased frequencies of basal cells were detected in exfoliated buccal cells (BMCyt). • Increased frequencies of micronucleus and cytotoxicity were observed in BMCyt assay. • Anesthesiologists have genomic instability due to occupational exposure. - Abstract: Data on the genotoxic and mutagenic effects of occupational exposure to the most frequently used volatile anesthetics are limited and controversial. The current study is the first to evaluate genomic instability, cell death and proliferative index in exfoliated buccal cells (EBC) from anesthesiologists. We also evaluated DNA damage and determined the concentrations of the anesthetic gases most commonly used in operating rooms. This study was conducted on physicians who were allocated into two groups: the exposed group, which consisted of anesthesiologists who had been exposed to waste anesthetic gases (isoflurane, sevoflurane, desflurane and nitrous oxide − N 2 O) for at least two years; and the control group, which consisted of non-exposed physicians matched for age, sex and lifestyle with the exposed group. Venous blood and EBC samples were collected from all participants. Basal DNA damage was evaluated in lymphocytes by the comet assay, whereas the buccal micronucleus (MN) cytome (BMCyt) assay was applied to evaluate genotoxic and cytotoxic effects. The concentrations of N 2 O and anesthetics were measured via a portable infrared spectrophotometer. The average concentration of waste gases was greater than 5 parts per million (ppm) for all of the halogenated anesthetics and was more than 170 ppm for N 2 O, expressed as a time-weighted average. There was no significant difference between the groups in relation to lymphocyte DNA damage. The exposed group had higher frequencies of MN, karyorrhexis and pyknosis, and

  1. Occupational exposure to anesthetics leads to genomic instability, cytotoxicity and proliferative changes

    Energy Technology Data Exchange (ETDEWEB)

    Souza, Kátina M.; Braz, Leandro G.; Nogueira, Flávia R.; Souza, Marajane B.; Bincoleto, Lahis F.; Aun, Aline G. [Faculdade de Medicina de Botucatu, UNESP − Univ Estadual Paulista, Departamento de Anestesiologia, Botucatu (Brazil); Corrente, José E.; Carvalho, Lídia R. [Instituto de Biociências de Botucatu, UNESP − Univ Estadual Paulista, Departamento de Bioestatística, Botucatu (Brazil); Braz, José Reinaldo C. [Faculdade de Medicina de Botucatu, UNESP − Univ Estadual Paulista, Departamento de Anestesiologia, Botucatu (Brazil); Braz, Mariana G., E-mail: mgbraz@hotmail.com [Faculdade de Medicina de Botucatu, UNESP − Univ Estadual Paulista, Departamento de Anestesiologia, Botucatu (Brazil)

    2016-09-15

    Highlights: • Anesthesiologists exposed to the most commonly used anesthetic gases were evaluated. • No alterations were detected for lymphocyte DNA damage detected by the comet assay. • Decreased frequencies of basal cells were detected in exfoliated buccal cells (BMCyt). • Increased frequencies of micronucleus and cytotoxicity were observed in BMCyt assay. • Anesthesiologists have genomic instability due to occupational exposure. - Abstract: Data on the genotoxic and mutagenic effects of occupational exposure to the most frequently used volatile anesthetics are limited and controversial. The current study is the first to evaluate genomic instability, cell death and proliferative index in exfoliated buccal cells (EBC) from anesthesiologists. We also evaluated DNA damage and determined the concentrations of the anesthetic gases most commonly used in operating rooms. This study was conducted on physicians who were allocated into two groups: the exposed group, which consisted of anesthesiologists who had been exposed to waste anesthetic gases (isoflurane, sevoflurane, desflurane and nitrous oxide − N{sub 2}O) for at least two years; and the control group, which consisted of non-exposed physicians matched for age, sex and lifestyle with the exposed group. Venous blood and EBC samples were collected from all participants. Basal DNA damage was evaluated in lymphocytes by the comet assay, whereas the buccal micronucleus (MN) cytome (BMCyt) assay was applied to evaluate genotoxic and cytotoxic effects. The concentrations of N{sub 2}O and anesthetics were measured via a portable infrared spectrophotometer. The average concentration of waste gases was greater than 5 parts per million (ppm) for all of the halogenated anesthetics and was more than 170 ppm for N{sub 2}O, expressed as a time-weighted average. There was no significant difference between the groups in relation to lymphocyte DNA damage. The exposed group had higher frequencies of MN, karyorrhexis and

  2. Environmental lead exposure is associated with visit-to-visit systolic blood pressure variability in the US adults.

    Science.gov (United States)

    Faramawi, Mohammed F; Delongchamp, Robert; Lin, Yu-Sheng; Liu, Youcheng; Abouelenien, Saly; Fischbach, Lori; Jadhav, Supriya

    2015-04-01

    The association between environmental lead exposure and blood pressure variability, an important risk factor for cardiovascular disease, is unexplored and unknown. The objective of the study was to test the hypothesis that lead exposure is associated with blood pressure variability. American participants 17 years of age or older from National Health and Nutrition Examination Survey III were included in the analysis. Participants' blood lead concentrations expressed as micrograms per deciliter were determined. The standard deviations of visit-to-visit systolic and diastolic blood pressure were calculated to determine blood pressure variability. Multivariable regression analyses adjusted for age, gender, race, smoking and socioeconomic status were employed. The participants' mean age and mean blood lead concentration were 42.72 years and 3.44 mcg/dl, respectively. Systolic blood pressure variability was significantly associated with environmental lead exposure after adjusting for the effect of the confounders. The unadjusted and adjusted means of visit-to-visit systolic blood pressure variability and the β coefficient of lead exposure were 3.44, 3.33 mcg/dl, β coefficient = 0.07, P variability. Screening adults with fluctuating blood pressure for lead exposure could be warranted.

  3. Effect of screening current induced pair breaking on magnetization of superconducting lead nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Yashwant, G.; Prajapat, C.L. [Technical Physics and Prototype Engineering Division, Bhabha Atomic Research Centre, Mumbai, Maharashtra 400 085 (India); Jayakumar, O.D. [Chemistry Division, Bhabha Atomic Research Centre, Mumbai, Maharashtra 400 085 (India); Singh, M.R.; Gupta, S.K. [Technical Physics and Prototype Engineering Division, Bhabha Atomic Research Centre, Mumbai, Maharashtra 400 085 (India); Tyagi, A.K. [Chemistry Division, Bhabha Atomic Research Centre, Mumbai, Maharashtra 400 085 (India); Ravikumar, G. [Technical Physics and Prototype Engineering Division, Bhabha Atomic Research Centre, Mumbai, Maharashtra 400 085 (India)], E-mail: gurazada@barc.gov.in

    2008-06-15

    Magnetization measurements on lead nanoparticles in the size range 35-45 nm are presented. It is shown that the critical fields in these nanoparticles are enhanced significantly above their bulk values with temperature dependence also distinct from that of bulk. The observed 'type II' like shape of the magnetization curves is explained on the basis of the Ginzburg-Landau phenomenology by invoking the pair breaking effect of the London screening currents, which makes the effective penetration depth an increasing function of the field. The temperature dependence of critical field is found to be consistent with our explanation.

  4. Combination Therapy for the Cardiovascular Effects of Perinatal Lead Exposure in Young and Adult Rats

    International Nuclear Information System (INIS)

    Gaspar, Andréia Fresneda; Cordellini, Sandra

    2014-01-01

    Combination therapy can play a significant role in the amelioration of several toxic effects of lead (Pb) and recovery from associated cardiovascular changes. To investigate the effects of combination therapy on the cardiovascular effects of perinatal lead exposure in young and adult rats Female Wistar rats received drinking water with or without 500 ppm of Pb during pregnancy and lactation. Twenty-two- and 70-day-old rat offspring who were or were not exposed to Pb in the perinatal period received meso-dimercaptosuccinic acid (DMSA), L-arginine, or enalapril and a combination of these compounds for 30 additional days. Noradrenaline response curves were plotted for intact and denuded aortas from 23-, 52-, 70-, and 100-day-old rats stratified by perinatal Pb exposure (exposed/unexposed) and treatment received (treated/untreated). Systolic blood pressure was evaluated and shown to be higher in the 23-, 52-, 70-, and 100-day age groups with Pb exposure than in the corresponding control age groups: 117.8 ± 3.9*, 135.2 ± 1.3*, 139.6 ± 1.6*, and 131.7 ± 2.8*, respectively and 107.1 ± 1.8, 118.8 ± 2.1, 126.1 ± 1.1, and 120.5 ± 2.2, respectively (p < 0.05). Increased reactivity to noradrenaline was observed in intact, but not denuded, aortas from 52-, 70-, and 100-day-old exposed rats, and the maximum responses (g of tension) in the respective Pb-exposed and control age groups were as follows: 3.43 ± 0.16*, 4.32 ± 0.18*, and 4.21 ± 0.23*, respectively and 2.38 ± 0.33, 3.37 ± 0.13, and 3.22 ± 0.21, respectively (p < 0.05). All treatments reversed the changes in vascular reactivity to noradrenaline in rats perinatally exposed to Pb. The combination therapy resulted in an earlier restoration of blood pressure in Pb-exposed rats compared with the monotherapies, except for enalapril therapy in young rats. These findings represent a new approach to the development of therapeutic protocols for the treatment of Pb-induced hypertension

  5. Blood Lead Levels and Risk Factors for Lead Exposure in a Pediatric Population in Ho Chi Minh City, Vietnam

    Directory of Open Access Journals (Sweden)

    Deborah Havens

    2018-01-01

    Full Text Available Although lead recycling activities are a known risk factor for elevated blood levels in South East Asia, little is known regarding the prevalence of and risk factors for elevated blood lead levels (BLL among the general pediatric population in Vietnam. This study is a cross-sectional evaluation of 311 children from Children’s Hospital #2 in Ho Chi Minh City, Vietnam. Capillary blood lead testing was performed using the LeadCare II. Mean BLLs were 4.97 μg/dL (Standard Deviation (SD 5.50, with 7% of the participants having levels greater than 10 μg/dL. Living in Bing Duong province (OR 2.7, 95% CI 1.4–5.6.1 or the Dong Nai province (OR 2.3, 95% CI 1.0–5.1 and having an age greater than 12 months (OR 6.0, 95% CI 3.1–11.8 were associated with higher BLLs. The prevalence of elevated BLLs in Vietnam is consistent with other SE Asian countries. Mean BLLs in Ho Chi Minh City are markedly less than those seen in a separate study of children living near lead recycling activities. Additional evaluation is necessary to better detail potential risk factors if screening is to be implemented within Vietnam.

  6. Sampling in schools and large institutional buildings: Implications for regulations, exposure and management of lead and copper.

    Science.gov (United States)

    Doré, Evelyne; Deshommes, Elise; Andrews, Robert C; Nour, Shokoufeh; Prévost, Michèle

    2018-04-21

    Legacy lead and copper components are ubiquitous in plumbing of large buildings including schools that serve children most vulnerable to lead exposure. Lead and copper samples must be collected after varying stagnation times and interpreted in reference to different thresholds. A total of 130 outlets (fountains, bathroom and kitchen taps) were sampled for dissolved and particulate lead as well as copper. Sampling was conducted at 8 schools and 3 institutional (non-residential) buildings served by municipal water of varying corrosivity, with and without corrosion control (CC), and without a lead service line. Samples included first draw following overnight stagnation (>8h), partial (30 s) and fully (5 min) flushed, and first draw after 30 min of stagnation. Total lead concentrations in first draw samples after overnight stagnation varied widely from 0.07 to 19.9 μg Pb/L (median: 1.7 μg Pb/L) for large buildings served with non-corrosive water. Higher concentrations were observed in schools with corrosive water without CC (0.9-201 μg Pb/L, median: 14.3 μg Pb/L), while levels in schools with CC ranged from 0.2 to 45.1 μg Pb/L (median: 2.1 μg Pb/L). Partial flushing (30 s) and full flushing (5 min) reduced concentrations by 88% and 92% respectively for corrosive waters without CC. Lead concentrations were 45% than values in 1st draw samples collected after overnight stagnation. Concentrations of particulate Pb varied widely (≥0.02-846 μg Pb/L) and was found to be the cause of very high total Pb concentrations in the 2% of samples exceeding 50 μg Pb/L. Pb levels across outlets within the same building varied widely (up to 1000X) especially in corrosive water (0.85-851 μg Pb/L after 30MS) confirming the need to sample at each outlet to identify high risk taps. Based on the much higher concentrations observed in first draw samples, even after a short stagnation, the first 250mL should be discarded unless no sources

  7. Effects of dietary lead exposure on vitamin levels in great tit nestlings – An experimental manipulation

    International Nuclear Information System (INIS)

    Ruiz, Sandra; Espín, Silvia; Rainio, Miia; Ruuskanen, Suvi; Salminen, Juha-Pekka; Lilley, Thomas M.; Eeva, Tapio

    2016-01-01

    Exposure to metal pollution negatively affects animal physiology, including nutrient metabolism, but in the wild an effect can seldom be attributed to a single metal. Moreover, little is known about how the metabolism of vitamins, essential micronutrients for developing juveniles, is affected by toxic metals. Therefore we experimentally investigated the effects of lead (Pb), a widespread toxic metal, on four fat-soluble vitamins A (total and retinol), D 3 , E (total and α-tocopherol) and K and carotenoids (lutein, zeaxanthin and unidentified) in great tit (Parus major) nestlings. In addition to a control group where no Pb was provided, two Pb-dosed groups were compared to a metal exposed group in the vicinity of a Ni–Cu smelter. We examined whether Pb treatment affects vitamin homeostasis and how the response of Pb-treated birds relates to that of a population under industrial exposure of Pb and other metals. For this purpose, vitamin and carotenoid levels were quantified with UPLC-MS from plasma of 7 days-old nestlings. All metal exposed groups showed increased vitamin A and retinol levels. However, vitamin levels were not directly associated with fecal Pb levels, with the exception of retinol, which was positively correlated with fecal Pb. Alpha-tocopherol, lutein and zeaxanthin levels were positively associated with body mass and wing growth rate. To conclude, Pb exposure increased plasma vitamin A and retinol levels while the levels of other vitamins and carotenoids rather reflected secondary pollution effects via differences in habitat and diet quality at the smelter site. Our findings suggest Pb exposed nestlings may allocate the vitamins needed for growth and development to fight the physiological stress thus compromising their fitness. - Highlights: • Pb effects on vitamins A, D 3 , E and K in wild great tit nestlings were investigated. • Four treatment groups were established: Control, Low-Pb, High-Pb and Smelter. • Pb concentrations measured in

  8. Elevated lead levels from e-waste exposure are linked to decreased olfactory memory in children.

    Science.gov (United States)

    Zhang, Bo; Huo, Xia; Xu, Long; Cheng, Zhiheng; Cong, Xiaowei; Lu, Xueling; Xu, Xijin

    2017-12-01

    Lead (Pb) is a developmental neurotoxicant and can cause abnormal development of the nervous system in children. Hence, the aim of this study was to investigate the effect of Pb exposure on child olfactory memory by correlating the blood Pb levels of children in Guiyu with olfactory memory tests. We recruited 61 preschool children, 4- to 7-years of age, from Guiyu and 57 children from Haojiang. The mean blood Pb level of Guiyu children was 9.40 μg/dL, significantly higher than the 5.04 μg/dL mean blood Pb level of Haojiang children. In addition, approximately 23% of Guiyu children had blood Pb levels exceeding 10.00 μg/dL. The correlation analysis showed that blood Pb levels in children highly correlated with e-waste contact (r s  = 0.393). Moreover, the mean concentration of serum BDNF in Guiyu children (35.91 ng/ml) was higher than for Haojiang (28.10 ng/ml) and was positively correlated with blood Pb levels. Both item and source olfactory memory tests at 15 min, 5 h and 24 h after odor exposure showed that scores were lower in Guiyu children indicative of reduced olfactory memory in Guiyu children. Olfactory memory tests scores negatively correlated with blood Pb and serum BDNF levels, but were positively associated with parental education levels. At the same time, scores of both tests on children in the high blood Pb level group (blood Pb levels > 5.00 μg/dL) were lower than those in the low blood Pb level group (blood Pb levels ≤ 5.00 μg/dL), implying that Pb exposure decreases olfactory memory in children. Our findings suggest that Pb exposure in e-waste recycling and dismantling areas could result in an increase in serum BDNF level and a decrease in child olfactory memory, in addition, BDNF might be involved in olfactory memory impairment. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Effect of Perinatal Lead Exposure on the Social Behaviour of Laboratory Mice Offspring at Adolescent Age

    International Nuclear Information System (INIS)

    AbuTaweel Qasim M; Ajarem Jamaan S

    2008-01-01

    Lead ( Pb ) was given to Swiss-Webster female mice at the concentrations of 0.1 and 0.2% ( w/v ) , containing 550 and 1100 ppm of lead respectively, in their drinking water. Treatment started from day 1 of pregnancy until day 15 postnatally . Thereafter, the dams were switched to plain tap water. After the weaning period ( 21 days ), all male offspring were isolated (one animal per cage) for 14 days, and the isolated male offspring were subjected to 'Standard Opponenttest' at the age of 36 days . the results of this test showed a significant and dose-dependent increase in the non-social behaviour , whereas such results showed a significant decline in the social behaviour including naso-genital and naso-nasal contact, number of fights, rear, wall rear and displacement activities of the Pb exposed young adult male offspring. The present perinatal Pb effects in the male offspring are possibly via in utero exposure and/or via mother's milk. (author)

  10. Occupational and environmental lead exposure in Port Harcourt, Nigeria: analysis of its association with renal function indices.

    Science.gov (United States)

    Alasia, D D; Emem-Chioma, P C; Wokoma, F S

    2010-01-01

    In spite of the high risk of lead exposure in Nigeria, there is a paucity of data on the occupational and environmental burden of lead exposure and its impact on human health especially its nephrotoxic effects. This study aims to assess the degree of occupational and environmental lead exposure in Port Harcourt Nigeria and the relationship between lead exposure and indices of renal function. A cross sectional comparative study of 190 aduIt subjects with occupational lead exposure and 80 matched controls. Blood lead was used as the biomarker of lead exposure. Serum urea, creatinine, uric acid, urine albumin and glomerular filtration rate were the renal function indices measured. Occupationally lead exposed subjects had higher mean blood lead 50.37 +/- 24.58 ug/dI, than controls 41.40 +/- 26.85 ug/dl (p = 0.008). The mean values of serum urea, creatinine and uric acid were significantly higher in study subjects compared to controls 3.06 +/- 0.81 mmol/L vs. 2.7 +/- 0.84 mmol/L (p = 0.002), 87.2 +/- 14.30 umol/L vs. 80.68 +/- 14.70 umol/L (p = 0.001) and 271.93 +/- 71.18 umol/L vs. 231.1 +/- 62.70 umol/L (p = 0.000) respectively. Creatinine clearance was significantly lower in subjects compared to controls 98.86 +/- 21.26 mI/min/1.72m2 vs. 108.18 +/- 25.16 mI/min/1.72m2 (p = 0.002). Blood lead correlated positively only with blood urea [r = .031, r2 = .017, p = .031] and negatively [r = -.144, r2 = .02 1, p = .018] with serum phosphate. The level of environmental and occupational lead exposure in Port Harcourt, Nigeria is high, with occupational lead exposure increasing the risk of lead toxicity and renal function impairment.

  11. The Pb isotopic record of historical to modern human lead exposure

    International Nuclear Information System (INIS)

    Kamenov, George D.; Gulson, Brian L.

    2014-01-01

    Human teeth and bones incorporate trace amounts of lead (Pb) from the local environment during growth and remodeling. Anthropogenic activities have caused changes in the natural Pb isotopic background since historical times and this is reflected in the Pb isotopes of historical European teeth. Lead mining and use increased exponentially during the last century and the isotopic compositions of modern human teeth reflect the modern anthropogenic Pb. USA teeth show the most radiogenic Pb and Australian teeth show the least radiogenic Pb, a result of different Pb ores used in the two regions. During the last century the Australian Pb was exported to Europe, Asia, South America, and Africa, resulting in swamping of the local environmental Pb signal by the imported Pb. As a result, the modern human teeth in Europe show a significant drop to lower isotopic values compared with historical times. Similarly, modern human teeth in other regions of the world show similar Pb isotopic ratios to modern European teeth reflecting the Pb imports. The specific pattern of human Pb exposure allows us to use the Pb isotopic signal recorded in the skeleton as a geo-referencing tool. As historical European teeth show a distinct Pb signal, we can identify early European skeletal remains in the New World and likely elsewhere. In modern forensic investigations we can discriminate to some extent Eastern Europeans from Western and Northern Europeans. Australians can be identified to some extent in any region in the world, although there is some overlap with Western European individuals. Lead isotopes can be used to easily identify foreigners in the USA, as modern USA teeth are distinct from any other region of the world. By analogy, USA individuals can be identified virtually in any other region of the world. - Highlights: • We present high-precision Pb isotope data for historical and modern human teeth. • Human teeth reflect human Pb exposure since historical times. • Modern teeth show

  12. The Pb isotopic record of historical to modern human lead exposure

    Energy Technology Data Exchange (ETDEWEB)

    Kamenov, George D., E-mail: kamenov@ufl.edu [Department of Geological Sciences, University of Florida, 241 Williamson Hall, Gainesville, FL 32611 (United States); Gulson, Brian L. [Graduate School of the Environment, Faculty of Science, Macquarie University, Sydney, NSW 2109 (Australia)

    2014-08-15

    Human teeth and bones incorporate trace amounts of lead (Pb) from the local environment during growth and remodeling. Anthropogenic activities have caused changes in the natural Pb isotopic background since historical times and this is reflected in the Pb isotopes of historical European teeth. Lead mining and use increased exponentially during the last century and the isotopic compositions of modern human teeth reflect the modern anthropogenic Pb. USA teeth show the most radiogenic Pb and Australian teeth show the least radiogenic Pb, a result of different Pb ores used in the two regions. During the last century the Australian Pb was exported to Europe, Asia, South America, and Africa, resulting in swamping of the local environmental Pb signal by the imported Pb. As a result, the modern human teeth in Europe show a significant drop to lower isotopic values compared with historical times. Similarly, modern human teeth in other regions of the world show similar Pb isotopic ratios to modern European teeth reflecting the Pb imports. The specific pattern of human Pb exposure allows us to use the Pb isotopic signal recorded in the skeleton as a geo-referencing tool. As historical European teeth show a distinct Pb signal, we can identify early European skeletal remains in the New World and likely elsewhere. In modern forensic investigations we can discriminate to some extent Eastern Europeans from Western and Northern Europeans. Australians can be identified to some extent in any region in the world, although there is some overlap with Western European individuals. Lead isotopes can be used to easily identify foreigners in the USA, as modern USA teeth are distinct from any other region of the world. By analogy, USA individuals can be identified virtually in any other region of the world. - Highlights: • We present high-precision Pb isotope data for historical and modern human teeth. • Human teeth reflect human Pb exposure since historical times. • Modern teeth show

  13. Effects of early-life lead exposure on oxidative status and phagocytosis activity in great tits (Parus major)

    NARCIS (Netherlands)

    Rainio, Miia J.; Eeva, Tapio; Lilley, Thomas; Stauffer, Janina; Ruuskanen, Suvi

    2015-01-01

    Abstract Lead is a highly poisonous metal with a very long half-life, distributing throughout the body in blood and accumulating primarily in bones and kidney. We studied the short and long-term effects of early-life lead exposure on antioxidant defense and phagocytosis activity in a small passerine

  14. Response of TLD badge for the estimation of exposure conditions in diagnostic x-ray departments - use of lead aprons

    International Nuclear Information System (INIS)

    Pradhan, A.S.; Chatterjee, S.; Bakshi, A.K.

    2002-01-01

    The present study was undertaken to ascertain the conditions of exposure of the TLD badge and to evaluate the inaccuracy involved in the estimation of dose received by the worker using an averaged lead apron transmission factor for the use of the badge above lead apron

  15. Exposure of the endangered Milky stork population to cadmium and lead via food and water intake in Kuala Gula Bird Sanctuary, Perak, Malaysia

    OpenAIRE

    Rahman, Faid; Ismail, Ahmad; Omar, Hishamuddin; Hussin, Mohamed Zakaria

    2017-01-01

    The Milky stork is listed as an endangered species endemic to the Southeast Asia region. In Malaysia, the population is currently being reintroduced back into the wild. However, the increase of anthropogenic activity throughout the coastal area might expose the population to hazardous chemicals such as heavy metals. This study highlights the contamination of cadmium (Cd) and lead (Pb) in the Milky storkâs diet. Additionally, this is the first time an integrated exposure model being used to as...

  16. Effect of histochrome on the severity of delayed effects of prenatal exposure to lead nitrate in the rat brain.

    Science.gov (United States)

    Ryzhavsky, B Ya; Lebedko, O A; Belolubskaya, D S

    2008-08-01

    The effects of histochrome on the severity of delayed effects of prenatal exposure to lead nitrate were studied in the rat brain. Exposure of pregnant rats to lead nitrate during activation of free radical oxidation reduced activity of NADH- and NADPH-dehydrogenases in cortical neurons of their 40-day-old progeny, reduced the number of neurons in a visual field, increased the number of pathologically modified neurons, and stimulated rat motor activity in an elevated plus-maze. Two intraperitoneal injections of histochrome in a dose of 0.1 mg/kg before and after lead citrate challenge attenuated the manifestations of oxidative stress and prevented the changes in some morphological and histochemical parameters of the brain, developing under the effect of lead exposure.

  17. Lead exposure and biological effects in pied flycatchers (Ficedula hypoleuca) before and after the closure of a lead mine in northern Sweden

    International Nuclear Information System (INIS)

    Berglund, A.M.M.; Ingvarsson, P.K.; Danielsson, H.; Nyholm, N.E.I.

    2010-01-01

    Mining activities affect the surrounding environment by increasing exposure to metals. In this study, metal accumulation and its effects on reproduction and health of pied flycatcher (Ficedula hypoleuca) nestlings were monitored before and up to five years after a lead mine and enrichment plant closed down. The lead concentration in moss, nestling blood, liver and feces all indicated decreased lead exposure by at least 31% after closure, although only blood lead decreased significantly. Although the birds responded fairly well to the changed atmospheric deposition (based on moss samples), concentrations were still higher compared with birds in a reference area, and breeding was affected at the mine (smaller clutches and higher mortality). Surviving nestlings suffered from lower hemoglobin levels, mean cell hemoglobin concentrations and inhibited δ-aminolevulinic acid dehydratase activity. Lead poisoning contributed to poor health and adverse reproductive effects, but other factors (e.g. increased parasitic load) probably also affected the birds. - Increased mortality and lower blood values in pied flycatcher (Ficedula hypoleuca) nestlings near a closed lead mine.

  18. Low-level environmental lead exposure in childhood and adult intellectual function: a follow-up study

    Directory of Open Access Journals (Sweden)

    Gregas Matthew

    2011-03-01

    Full Text Available Abstract Background Early life lead exposure might be a risk factor for neurocognitive impairment in adulthood. Objectives We sought to assess the relationship between early life environmental lead exposure and intellectual function in adulthood. We also attempted to identify which time period blood-lead concentrations are most predictive of adult outcome. Methods We recruited adults in the Boston area who had participated as newborns and young children in a prospective cohort study that examined the relationship between lead exposure and childhood intellectual function. IQ was measured using the Wechsler Abbreviated Scale of Intelligence (WASI. The association between lead concentrations and IQ scores was examined using linear regression. Results Forty-three adults participated in neuropsychological testing. Childhood blood-lead concentration (mean of the blood-lead concentrations at ages 4 and 10 years had the strongest relationship with Full-Scale IQ (β = -1.89 ± 0.70, p = 0.01. Full-scale IQ was also significantly related to blood-lead concentration at age 6 months (β = -1.66 ± 0.75, p = 0.03, 4 years (β = -0.90 ± 0.41, p = 0.03 and 10 years (β = -1.95 ± 0.80, p = 0.02. Adjusting for maternal IQ altered the significance of the regression coefficient. Conclusions Our study suggests that lead exposure in childhood predicts intellectual functioning in young adulthood. Our results also suggest that school-age lead exposure may represent a period of increased susceptibility. Given the small sample size, however, the potentially confounding effects of maternal IQ cannot be excluded and should be evaluated in a larger study.

  19. Waste dumpsites and public health: a case for lead exposure in Zimbabwe and potential global implications.

    Science.gov (United States)

    Tongesayi, Tsanangurayi; Kugara, Jameson; Tongesayi, Sunungurai

    2018-02-01

    Most waste sites in Zimbabwe are not sanitary landfills but open dumps that indiscriminately receive waste from municipalities, industries, commercial establishments, and social services establishments. People, including children, who eke out a living through scavenging the dumps expose themselves to environmental pollutants at the dumps via inadvertent ingestion and inhalation of contaminated dust, and dermal absorption. The public is potentially being exposed to a slew of the pollutants via air, water, and food, all contaminated by uncontrolled leachates and aerially deposited dust and particulates from the sites. One of the unfortunate consequences of globalization is the sharing of contaminated food and the associated disease burdens; hence, regional contamination can have global impacts. We analyzed the levels of lead at two waste sites in Zimbabwe to assess the daily exposure levels of Pb to children and adults who scavenge the sites as well as determine levels of the heavy metal that are potentially contaminating air, water, soils, and food in the country. Levels of Pb ranged from 23,000 to 14,600,000 µg/kg at one of the sites and from 30,000 to 1,800,000 µg/kg at the other. Inadvertent daily exposure amounts that were calculated by assuming an inadvertent daily ingestion of 20-500 mg of soil/dust were mostly higher than the provisional tolerable daily intake established by the World Health Organization for infants, children, and adults. The XRF measurements were validated using certified reference samples, 2710a (Montana soil) and 2781 (domestic sludge), from the National Institute of Standards and Technology.

  20. The relationship between occupational exposure to lead and manifestation of cardiovascular complications in persons with arterial hypertension

    International Nuclear Information System (INIS)

    Poreba, Rafal; Gac, Pawel; Poreba, Malgorzata; Andrzejak, Ryszard

    2010-01-01

    The chronic exposure to lead represents a risk factor of arterial hypertension development. Ambulatory blood pressure monitoring is the most prognostically reliable method of measuring of arterial blood pressure. The study is aimed at evaluating the relationship between occupational exposure to lead and manifestation of cardiovascular complications in patients with arterial hypertension. The studies included 73 men (mean age, 54.26 ± 8.17 years) with arterial hypertension, treated with hypotensive drugs: group I-persons occupationally exposed to lead (n = 35) and group II-individuals not exposed to lead (n = 38). An analysis of results obtained during ambulatory blood pressure monitoring disclosed significantly higher values of mean systolic blood pressure, mean blood pressure, pulse pressure, and variability of systolic blood pressure in the group of hypertensive patients occupationally exposed to lead as compared to patients with arterial hypertension but not exposed to lead. The logistic regression showed that a more advanced age, higher concentration of blood zinc protoporphyrin, and a higher mean value of pulse pressure represented independent risk factors of left ventricular hypertrophy in the group of persons with arterial hypertension and chronically exposed to lead (OR age = 1.11; OR ZnPP = 1.32; OR PP = 1,43; p < 0.05). In view of the above data demonstration that occupational exposure to lead represents an independent risk factor of increased pulse pressure may be of key importance in the process of shaping general social awareness as to harmful effects of lead compounds on human health.

  1. Prenatal exposure to lead and cognitive deficit in 7- and 14-year-old children in the presence of concomitant exposure to similar molar concentration of methylmercury

    DEFF Research Database (Denmark)

    Yorifuji, Takashi; Debes, Frodi; Weihe, Pal

    2011-01-01

    1986-1987 from whom lead was measured in cord-blood. A total of 896 cohort subjects participated in a clinical examination at age 7 and 808 subjects in a second examination at age 14. We evaluated the association between cord-blood lead concentrations and cognitive deficits (attention/working memory......, language, visuospatial, and memory) using multiple regression models. Overall, the lead concentration showed no clear pattern of association. However, in subjects with a low methylmercury exposure, after inclusion of statistical interaction terms, lead-associated adverse effects on cognitive functions were...

  2. Current exposure of 200 pregnant Danish women to phthalates, parabens and phenols

    DEFF Research Database (Denmark)

    Tefre de Renzy-Martin, Katrine; Frederiksen, Hanne; Christensen, Jeppe Hagstrup

    2014-01-01

    Many phthalates, parabens and phenols are suspected to have endocrine disrupting properties in humans. They are found in consumer products, including food wrapping, cosmetics and building materials. The foetus is vulnerable and exposure to these chemicals is of particular concern for pregnant women...... still raise concern. As current toxicological risk assessments in humans do not take into account simultaneous exposure, the true cumulative risk for the foetus may be underestimated....

  3. Gestational lead exposure selectively decreases retinal dopamine amacrine cells and dopamine content in adult mice.

    Science.gov (United States)

    Fox, Donald A; Hamilton, W Ryan; Johnson, Jerry E; Xiao, Weimin; Chaney, Shawntay; Mukherjee, Shradha; Miller, Diane B; O'Callaghan, James P

    2011-11-01

    Gestational lead exposure (GLE) produces supernormal scotopic electroretinograms (ERG) in children, monkeys and rats, and a novel retinal phenotype characterized by an increased number of rod photoreceptors and bipolar cells in adult mice and rats. Since the loss of dopaminergic amacrine cells (DA ACs) in GLE monkeys and rats contributes to supernormal ERGs, the retinal DA system was analyzed in mice following GLE. C57BL/6 female mice were exposed to low (27 ppm), moderate (55 ppm) or high (109 ppm) lead throughout gestation and until postnatal day 10 (PN10). Blood [Pb] in control, low-, moderate- and high-dose GLE was ≤ 1, ≤ 10, ~25 and ~40 μg/dL, respectively, on PN10 and by PN30 all were ≤ 1 μg/dL. At PN60, confocal-stereology studies used vertical sections and wholemounts to characterize tyrosine hydroxylase (TH) expression and the number of DA and other ACs. GLE dose-dependently and selectively decreased the number of TH-immunoreactive (IR) DA ACs and their synaptic plexus without affecting GABAergic, glycinergic or cholinergic ACs. Immunoblots and confocal revealed dose-dependent decreases in retinal TH protein expression and content, although monoamine oxidase-A protein and gene expression were unchanged. High-pressure liquid chromatography showed that GLE dose-dependently decreased retinal DA content, its metabolites and DA utilization/release. The mechanism of DA selective vulnerability is unknown. However, a GLE-induced loss/dysfunction of DA ACs during development could increase the number of rods and bipolar cells since DA helps regulate neuronal proliferation, whereas during adulthood it could produce ERG supernormality as well as altered circadian rhythms, dark/light adaptation and spatial contrast sensitivity. Copyright © 2011 Elsevier Inc. All rights reserved.

  4. Comparison and analysis of the efficiency of heat exchange of copper rod and copper wires current lead

    International Nuclear Information System (INIS)

    Fang, J.; Yu, T.; Li, Z.M.; Wei, B.; Qiu, M.; Zhang, H.J.

    2013-01-01

    Highlights: •An optimized design of HTS binary current leads is proposed. •Temperature distributions of two different current leads are calculated. •Experiments are done to certify the calculated temperature distributions. •The experiments proved that the copper wires increase security margins. -- Abstract: Current leads are the key components that connect the low-temperature and high temperature parts of the cryogenic system. Owing to the wide range of temperatures, current leads are the main sources of heat leakage. Since the HTS tapes have no resistance and the generated Joule heat is almost zero, HTS binary current leads can reduce heat leakage compared to the conventional leads. However, heat will still be generated and conducted to the cryogenic system through the copper parts of the HTS current leads. In order to reduce heat leakage by the copper parts of the HTS current leads, this paper presents an optimized design of the copper parts of HTS binary current leads. Inside the leads, the copper wires were applied as an alternative to the copper rod without changing the overall dimensions. Firstly, the differential function of heat transfer was derived. By solving the function, the optimum number of the copper wires and the temperature distribution of two different current leads were gotten. Then the experiment of the temperature distribution was done, and the experimental results were basically the same with the calculative results. The simulation and related experiments proved that the copper wire can increase security margins and reduce maximum temperatures under the same shunt current

  5. Comparison and analysis of the efficiency of heat exchange of copper rod and copper wires current lead

    Energy Technology Data Exchange (ETDEWEB)

    Fang, J., E-mail: fangseer@sina.com [School of Electrical Engineering, Beijing Jiaotong University, Beijing (China); Yu, T. [School of Electrical Engineering, Beijing Jiaotong University, Beijing (China); Li, Z.M.; Wei, B.; Qiu, M.; Zhang, H.J. [China Electric Power Research Institute, Haidian District, Beijing (China)

    2013-11-15

    Highlights: •An optimized design of HTS binary current leads is proposed. •Temperature distributions of two different current leads are calculated. •Experiments are done to certify the calculated temperature distributions. •The experiments proved that the copper wires increase security margins. -- Abstract: Current leads are the key components that connect the low-temperature and high temperature parts of the cryogenic system. Owing to the wide range of temperatures, current leads are the main sources of heat leakage. Since the HTS tapes have no resistance and the generated Joule heat is almost zero, HTS binary current leads can reduce heat leakage compared to the conventional leads. However, heat will still be generated and conducted to the cryogenic system through the copper parts of the HTS current leads. In order to reduce heat leakage by the copper parts of the HTS current leads, this paper presents an optimized design of the copper parts of HTS binary current leads. Inside the leads, the copper wires were applied as an alternative to the copper rod without changing the overall dimensions. Firstly, the differential function of heat transfer was derived. By solving the function, the optimum number of the copper wires and the temperature distribution of two different current leads were gotten. Then the experiment of the temperature distribution was done, and the experimental results were basically the same with the calculative results. The simulation and related experiments proved that the copper wire can increase security margins and reduce maximum temperatures under the same shunt current.

  6. Current densities in a pregnant woman model induced by simultaneous ELF electric and magnetic field exposure

    International Nuclear Information System (INIS)

    Cech, R; Leitgeb, N; Pediaditis, M

    2008-01-01

    The pregnant woman model SILVY was studied to ascertain to what extent the electric current densities induced by 50 Hz homogeneous electric and magnetic fields increase in the case of simultaneous exposure. By vectorial addition of the electric current densities, it could be shown that under worst case conditions the basic restrictions recommended by ICNIRP (International Commission on Non-Ionizing Radiation Protection) guidelines are exceeded within the central nervous system (CNS) of the mother, whereas in sole field exposure they are not. However, within the foetus the induced current densities do not comply with basic restrictions, either from single reference-level electric fields or from simultaneous exposure to electric and magnetic fields. Basic limits were considerably exceeded

  7. Secondhand smoke exposure and serum cotinine levels among current smokers in the USA.

    Science.gov (United States)

    Lindsay, Ryan P; Tsoh, Janice Y; Sung, Hai-Yen; Max, Wendy

    2016-03-01

    Secondhand smoke (SHS) likely provides additional exposure to nicotine and toxins for smokers, but has been understudied. Our objective was to determine whether SHS exposure among smokers yields detectable differences in cotinine levels compared with unexposed smokers at the population level. Using the US National Health and Nutrition Examination Survey (NHANES) for the years 1999-2012, we compared serum cotinine levels of 4547 current adult cigarette smokers stratified by self-reported SHS exposure sources (home and/or work) and smoking intensity. A weighted multivariable linear regression model determined the association between SHS exposure and cotinine levels among smokers. Smokers with SHS exposure at home (43.8%) had higher cotinine levels (β=0.483, p≤0.001) compared with those with no SHS exposure at home after controlling for the number of cigarettes smoked per day and number of days smoked in the previous 5 days, survey year, age, gender and education. Smokers with SHS exposure at work (20.0%) did not have significantly higher cotinine levels after adjustment. The adjusted geometric mean cotinine levels of light smokers (1-9 cigarettes per day) with no SHS exposure, exposure at work only, home only, and both home and work were 52.0, 62.7, 67.2, 74.4 ng/mL, respectively, compared with 219.4, 220.9, 255.2, 250.5 ng/mL among moderate/heavy smokers (≥10 cigarettes per day). Smokers living in residences where others smoke inside the home had significantly higher cotinine levels than smokers reporting no SHS exposure, regardless of individual smoking intensity. Future research should target the role that SHS exposure may have in nicotine dependence, cessation outcomes and other health impacts among smokers. 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/

  8. An analysis of multimodal occupational exposure leading to blood borne infections among health care workers

    OpenAIRE

    N Lakshmi Priya; K Usha Krishnan; G Jayalakshmi; S Vasanthi

    2015-01-01

    Occupational exposure poses a significant risk of transmission of blood-borne pathogens to healthcare workers (HCWs). Adherence to standard precautions, awareness about post exposure prophylaxis is poor in developing countries. This retrospective study analyzes the self-reported cases of occupational exposure in a tertiary care hospital. During the study period, 105 HCWs sustained occupational exposure to blood and body fluids. Majority of the victims 36 (34.2%) were interns and the clinical ...

  9. Arsenic, Cadmium and Lead Exposure and Immunologic Function in Workers in Taiwan.

    Science.gov (United States)

    Wu, Chin-Ching; Sung, Fung-Chang; Chen, Yi-Chun

    2018-04-05

    There has been growing concern over the impact of environmental exposure to heavy metals and other trace elements on immunologic functions. This study investigated men's arsenic (As), cadmium (Cd) and lead (Pb) contents in hair samples and their associations with immunological indicators, including white blood cell (WBC), lymphocyte and monocyte counts, and the immunoglobulin (Ig) levels including IgA, IgG and IgE. We recruited 133 men from one antimony trioxide manufacturing plant, two glass manufacturing plants and two plastics manufacturing plants. The mean concentration of Cd [0.16 (SD = 0.03) ug/g] was lower than means of As [0.86 (SD = 0.16) ug/g] and Pb [0.91 (SD = 0.22) ug/g] in hair samples, exerting no relationship with immunologic functions for Cd. The Spearman's correlation analysis showed a positive relationship between monocyte counts and hair Pb levels, but negative relations between As and IgG and between As and IgE. In conclusion, findings from these industry workers suggest that As levels in hair may have a stronger relation with immunologic function than Cd and PB have. Further research is needed to confirm the negative relationship.

  10. Arsenic, Cadmium and Lead Exposure and Immunologic Function in Workers in Taiwan

    Directory of Open Access Journals (Sweden)

    Chin-Ching Wu

    2018-04-01

    Full Text Available There has been growing concern over the impact of environmental exposure to heavy metals and other trace elements on immunologic functions. This study investigated men’s arsenic (As, cadmium (Cd and lead (Pb contents in hair samples and their associations with immunological indicators, including white blood cell (WBC, lymphocyte and monocyte counts, and the immunoglobulin (Ig levels including IgA, IgG and IgE. We recruited 133 men from one antimony trioxide manufacturing plant, two glass manufacturing plants and two plastics manufacturing plants. The mean concentration of Cd [0.16 (SD = 0.03 ug/g] was lower than means of As [0.86 (SD = 0.16 ug/g] and Pb [0.91 (SD = 0.22 ug/g] in hair samples, exerting no relationship with immunologic functions for Cd. The Spearman’s correlation analysis showed a positive relationship between monocyte counts and hair Pb levels, but negative relations between As and IgG and between As and IgE. In conclusion, findings from these industry workers suggest that As levels in hair may have a stronger relation with immunologic function than Cd and PB have. Further research is needed to confirm the negative relationship.

  11. Changes in regional brain GFAP levels and behavioral functioning following subchronic lead acetate exposure in adult rats

    NARCIS (Netherlands)

    Berg, K.J. van den; Lammers, J.H.C.M.; Hoogendijk, E.M.G.; Kulig, B.M.

    1996-01-01

    Adult male WAG/Rij/MBL rats were dosed with lead acetate at 0, 4.0, 8.0 or 12.5 mg/kg, 5 days per week for 4 weeks. Animals were assessed prior to exposure, at the end of the 4-week exposure period and after a 2-week recovery period using a functional observational battery (FOB) and motor activity

  12. The 12-lead electrocardiogram and risk of sudden death: current utility and future prospects.

    Science.gov (United States)

    Narayanan, Kumar; Chugh, Sumeet S

    2015-10-01

    More than 100 years after it was first invented, the 12-lead electrocardiogram (ECG) continues to occupy an important place in the diagnostic armamentarium of the practicing clinician. With the recognition of relatively rare but important clinical entities such as Wolff-Parkinson-White and the long QT syndrome, this clinical tool was firmly established as a test for assessing risk of sudden cardiac death (SCD). However, over the past two decades the role of the ECG in risk prediction for common forms of SCD, for example in patients with coronary artery disease, has been the focus of considerable investigation. Especially in light of the limitations of current risk stratification approaches, there is a renewed focus on this broadly available and relatively inexpensive test. Various abnormalities of depolarization and repolarization on the ECG have been linked to SCD risk; however, more focused work is needed before they can be deployed in the clinical arena. The present review summarizes the current knowledge on various ECG risk markers for prediction of SCD and discusses some future directions in this field. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2015. For permissions please email: journals.permissions@oup.com.

  13. An analysis of multimodal occupational exposure leading to blood borne infections among health care workers.

    Science.gov (United States)

    Priya, N Lakshmi; Krishnan, K Usha; Jayalakshmi, G; Vasanthi, S

    2015-01-01

    Occupational exposure poses a significant risk of transmission of blood-borne pathogens to healthcare workers (HCWs). Adherence to standard precautions, awareness about post exposure prophylaxis is poor in developing countries. This retrospective study analyzes the self-reported cases of occupational exposure in a tertiary care hospital. During the study period, 105 HCWs sustained occupational exposure to blood and body fluids. Majority of the victims 36 (34.2%) were interns and the clinical practice that led to the occupational exposure was withdrawal of blood (45.7%). Good infection control practices and emphasis on appropriate disposal are needed to increase the occupational safety for HCWs.

  14. An analysis of multimodal occupational exposure leading to blood borne infections among health care workers

    Directory of Open Access Journals (Sweden)

    N Lakshmi Priya

    2015-01-01

    Full Text Available Occupational exposure poses a significant risk of transmission of blood-borne pathogens to healthcare workers (HCWs. Adherence to standard precautions, awareness about post exposure prophylaxis is poor in developing countries. This retrospective study analyzes the self-reported cases of occupational exposure in a tertiary care hospital. During the study period, 105 HCWs sustained occupational exposure to blood and body fluids. Majority of the victims 36 (34.2% were interns and the clinical practice that led to the occupational exposure was withdrawal of blood (45.7%. Good infection control practices and emphasis on appropriate disposal are needed to increase the occupational safety for HCWs.

  15. How Exposure to ”Role Model” Projects Can Lead to Decisions for More Sustainable Infrastructure

    Directory of Open Access Journals (Sweden)

    Nora Harris

    2016-01-01

    Full Text Available A role model, whether an individual or a project, can inspire similar performance in others. This research examines such a phenomenon during the design process for more sustainable physical infrastructure. In this empirical study, engineering professionals (n = 54 were randomly assigned either a modified version of the Envision rating system for sustainable infrastructure, which was changed to include details from an exemplary role model project, or the current version of Envision, with no role model. Professionals given the role model version of Envision achieved on average 34% more points (SD = 27 than the control group (p = 0.001. A positive role model project appears to lead engineering professionals to higher goals for sustainability performance in their design decisions. This finding, and the corresponding line of interdisciplinary research, can be used in decision-structuring interventions, which are a relatively low-cost approach to support greater sustainability in physical infrastructure development.

  16. Non-occupational lead and cadmium exposure of adult women in Bangkok, Thailand

    International Nuclear Information System (INIS)

    Zhang, Z.-W.; Shimbo, S.; Watanabe, T.; Srianujata, S.; Banjong, O.; Chitchumroonchokchai, C.; Nakatsuka, H.; Matsuda-Inoguchi, N.; Higashikawa, K.; Ikeda, M.

    1999-01-01

    This survey was conducted to examine the extent of the exposure of Bangkok citizens to lead (Pb) and cadmium (Cd), and to evaluate the role of rice as the source of these heavy metals. In practice, 52 non-smoking adult women in an institution in the vicinity of Bangkok, volunteered to offer blood, spot urine, boiled rice and 24-h total food duplicate samples. Samples were wet-ashed, and then analyzed for Pb and Cd by ICP-MS. Geometric means for the levels in blood (Pb-B and Cd-B) and urine (Pb-U and Cd-U as corrected for creatinine concentration), and also for dietary intake (Pb-F and Cd-F) were 32.3 μg/l for Pb-B, 0.41 μg/l for Cd-B, 2.06 μg/g creatinine for Pb-U, 1.40 μg/g creatinine for Cd-U, 15.1 μg/day for Pb-F and 7.1 μg/day for Cd-F. Rice contributed 30% and 4% of dietary Cd and Pb burden, respectively. When compared with the counterpart values obtained in four neighboring cities in southeast Asia (i.e. Nanning, Tainan, Manila, and Kuala Lumpur), dietary Pb burden of the women in Bangkok was middle in the order among the values for the five cities. Pb level in the blood was the lowest of the levels among the five cities and Pb in urine was also among the low group. This apparent discrepancy in the order between Pb-B (i.e. the fifth) and Pb-F (the third) might be attributable to recent reduction of Pb levels in the atmosphere in Bangkok. Regarding Cd exposure, Cd levels in blood and urine as well as dietary Cd burden of Bangkok women were either the lowest or the next lowest among those in the five cities. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

  17. Lead emissions from road transport in Europe. A revision of current estimates using various estimation methodologies

    NARCIS (Netherlands)

    Denier van der Gon, H.A.C.; Appelman, W.

    2009-01-01

    Large-scale use of leaded gasoline was an important source of the neurotoxin lead in the European environment. After a sequence of regulations on the allowed gasoline lead content and, eventually, a ban on the use of lead additives in gasoline, road transport was no longer considered a source of

  18. Exposure of the endangered Milky stork population to cadmium and lead via food and water intake in Kuala Gula Bird Sanctuary, Perak, Malaysia.

    Science.gov (United States)

    Rahman, Faid; Ismail, Ahmad; Omar, Hishamuddin; Hussin, Mohamed Zakaria

    2017-01-01

    The Milky stork is listed as an endangered species endemic to the Southeast Asia region. In Malaysia, the population is currently being reintroduced back into the wild. However, the increase of anthropogenic activity throughout the coastal area might expose the population to hazardous chemicals such as heavy metals. This study highlights the contamination of cadmium (Cd) and lead (Pb) in the Milky stork's diet. Additionally, this is the first time an integrated exposure model being used to assess heavy metal exposure risk to the population. Lead level (5.5-7.98 mg kg -1 ) in particular was relatively high compared to Cd (0.08-0.33 mg kg -1 ). This was probably related to the different niches occupied by the species in the aquatic environment. The results further show that the predicted exposure doses (through intake of both food and water) for all metals are much lower than the Tolerable Daily Intake (TDI) values. The total exposure dose for Cd was 0.11 mg kg -1  d -1 with TDI value of 0.54 mg kg -1  d -1 while Pb total exposure dose was 0.31 mg kg -1  d -1 with TDI value of 0.64 mg kg -1  d -1 . Several possible factors that could lead to the observed pattern were discussed. In conclusion, there is an urgent need to improve the current habitat quality to protect the endangered species. The authors also emphasized on the protection of remaining Milky stork's habitats i.e. mudflats and mangroves and the creation of buffer zone to mitigate the negative impacts that may arise from pollution activity.

  19. High Tc superconducting current leads laser fabrication

    Directory of Open Access Journals (Sweden)

    Díez, J. C.

    1998-04-01

    Full Text Available In this work is described a laser float zone melting method designed in our laboratory to the development of superconductor Bi2Sr2CaCu2O8 current leads. The most relevant results obtained with different grown conditions and the influence of the process parameters in the properties of superconductor leads are presented.

    Las barras de alimentación basadas en el superconductor Bi2Sr2CaCu2O8 son de gran interés práctico para la fabricación de criogeneradores capaces de refrigerar bobinas superconductoras a temperaturas inferiores a 77 K e incluso cercanas a 5 K. Las propiedades mecánicas y eléctricas de dichas barras son fundamentales para determinar su grado de fiabilidad, que en última instancia determinar su aplicabilidad a escala comercial. Los parámetros de fabricación utilizando la fusión zonal inducida por láser permiten obtener fibras gruesas de este superconductor capaces de transportar elevadas corrientes a 77 K y a temperaturas inferiores, y con un comportamiento aceptable frente al ciclado térmico y al paso de elevadas intensidades de corriente eléctrica. En este trabajo se describe un sistema de fusión zonal láser diseñado en nuestro laboratorio para el desarrollo de superconductores y se resumen los resultados más significativos obtenidos según las diversas condiciones de crecimiento estudiadas, la influencia de los diversos parámetros de procesado utilizados sobre las propiedades de las fibras superconductoras obtenidas, así como su potencial uso en dispositivos prácticos.

  20. Cigarette Smoke Exposure during Pregnancy Alters Fetomaternal Cell Trafficking Leading to Retention of Microchimeric Cells in the Maternal Lung

    Science.gov (United States)

    Vogelgesang, Anja; Scapin, Cristina; Barone, Caroline; Tam, Elaine

    2014-01-01

    Cigarette smoke exposure causes chronic oxidative lung damage. During pregnancy, fetal microchimeric cells traffic to the mother. Their numbers are increased at the site of acute injury. We hypothesized that milder chronic diffuse smoke injury would attract fetal cells to maternal lungs. We used a green-fluorescent-protein (GFP) mouse model to study the effects of cigarette smoke exposure on fetomaternal cell trafficking. Wild-type female mice were exposed to cigarette smoke for about 4 weeks and bred with homozygote GFP males. Cigarette smoke exposure continued until lungs were harvested and analyzed. Exposure to cigarette smoke led to macrophage accumulation in the maternal lung and significantly lower fetal weights. Cigarette smoke exposure influenced fetomaternal cell trafficking. It was associated with retention of GFP-positive fetal cells in the maternal lung and a significant reduction of fetal cells in maternal livers at gestational day 18, when fetomaternal cell trafficking peaks in the mouse model. Cells quickly clear postpartum, leaving only a few, difficult to detect, persisting microchimeric cells behind. In our study, we confirmed the postpartum clearance of cells in the maternal lungs, with no significant difference in both groups. We conclude that in the mouse model, cigarette smoke exposure during pregnancy leads to a retention of fetal microchimeric cells in the maternal lung, the site of injury. Further studies will be needed to elucidate the effect of cigarette smoke exposure on the phenotypic characteristics and function of these fetal microchimeric cells, and confirm its course in cigarette smoke exposure in humans. PMID:24832066

  1. Widespread exposure to lead affects the body condition of free-living whooper swans Cygnus cygnus wintering in Britain

    International Nuclear Information System (INIS)

    Newth, J.L.; Rees, E.C.; Cromie, R.L.; McDonald, R.A.; Bearhop, S.; Pain, D.J.; Norton, G.J.; Deacon, C.; Hilton, G.M.

    2016-01-01

    Lead poisoning, through the ingestion of spent lead gunshot, is an established cause of morbidity and mortality in waterbirds globally, but the thresholds at which blood levels begin to affect the physiology of birds in the wild are less well known. Here we determine the prevalence of lead exposure in whooper swans and, for the first time, identify the level of blood lead associated with initial reductions in body condition. Blood lead elevated above background levels (i.e. >20 μg dL"−"1) was found in 41.7% (125/300) of swans tested. Blood lead was significantly negatively associated with winter body condition when levels were ≥44 μg dL"−"1 (27/260 = 10%). Our findings indicating that sub-lethal impacts of lead on body condition occur at the lower end of previously established clinical thresholds and that a relatively high proportion of individuals in this population may be affected, reaffirm the importance of reducing contamination of the environment with lead shot. - Highlights: • Elevated blood lead levels of >20 μg dL"−"1 were found in 41.7% of whooper swans. • Blood lead levels of ≥44 μg dL"−"1 were negatively associated with body condition. • Clinical effects were at lower levels than previously described for Anseriformes. • Reduction of lead shot in the environment would reduce the risk of lead exposure. - Blood lead was significantly negatively associated with the body condition of free-living whooper swans in winter when levels were ≥44 μg dL"−"1 (27/260 = 10% of birds were above this threshold).

  2. Lead exposure and early child neurodevelopment among children 12-24 months in Kinshasa, the Democratic Republic of Congo.

    Science.gov (United States)

    Kashala-Abotnes, Espérance; Mumbere, Pépé Penghele; Mishika, Jeannette Mukanya; Ndjukendi, Ally Omba; Mpaka, Davin Beya; Bumoko, Makila-Mabe Guy; Kayembe, Tharcisse Kalula; Tshala-Katumbay, Désiré; Kazadi, Théodore Kayembe; Okitundu, Daniel Luwa E-Andjafono

    2016-12-01

    Childhood lead exposure remains a problem in developing countries, and little is known about its effects on early child neurodevelopment and temperament in the Democratic Republic of Congo (DRC). We, therefore, conducted this study to determine the association between lead exposure and the neurodevelopment and behaviour of children aged 12-24 months in Kinshasa, DRC. A cross-sectional study was conducted between February and June 2012, and parents of 104 children were invited to participate. Blood lead levels (BLLs) of each child were tested using the flame atomic spectrophotometry method. All children were subject to a clinical examination and assessed with two selected early child neurodevelopmental tools, the Gensini-Gavito and the baby characteristics questionnaire, to measure their neurodevelopment and temperament. Detectable BLLs ranged from 1 to 30 μg/dl with a geometric mean of 6.9 (SD 4.8) μg/dl. BLLs at 5-9 and ≥10 μg/dl were significantly associated with the child temperament (p early child neurodevelopment and temperament. Children exposed to lead were reported with more temperament difficulties at even blood lead levels <10 μg/dl, suggesting the need for preventive and intervention measures to reduce lead exposure among children in Kinshasa, DRC.

  3. Test results of a 20 kA high temperature superconductor current lead using REBCO tapes

    Science.gov (United States)

    Heller, R.; Fietz, W. H.; Gröner, F.; Heiduk, M.; Hollik, M.; Lange, C.; Lietzow, R.

    2018-05-01

    The Karlsruhe Institute of Technology has developed a 20 kA high temperature superconductor (HTS) current lead (CL) using the second generation material REBCO, as industry worldwide concentrate on the production of this material. The aim was to demonstrate the possibility of replacing the Bi-2223/AgAu tapes by REBCO tapes, while for easy comparison of results, all other components are copies of the 20 kA HTS CL manufactured for the satellite tokamak JT-60SA. After the manufacture of all CL components including the newly developed REBCO module, the assembly of the CL has been executed at KIT and an experiment has been carried out in the CuLTKa test facility where the REBCO CL was installed and connected to a JT-60SA CL via a superconducting bus bar. The experiment covers steady state operation up to 20 kA, pulsed operation, measurement of the heat load at 4.5 K end, loss-of-flow-accident simulations, and quench performance studies. Here the results of these tests are reported and directly compared to those of the JT-60SA CL.

  4. The effects of lead exposure on the expression of HMGB1 and HO-1 in rats and PC12 cells.

    Science.gov (United States)

    Yang, Meiyuan; Li, Yaobin; Wang, Ying; Cheng, Nuo; Zhang, Yi; Pang, Shimin; Shen, Qiwei; Zhao, Lijuan; Li, Guilin; Zhu, Gaochun

    2018-05-15

    Lead (Pb) is an environmental neurotoxic metal. Chronic exposure to Pb causes deficits of learning and memory in children and spatial learning deficits in developing rats. In this study we investigated the effects of Pb exposure on the expression of HMGB1 and HO-1 in rats and PC12 cells. The animals were randomly divided to three groups: control group; low lead exposure group; high lead exposure group; PC12 cells were divided into 3 groups: 0 μM (control group), 1 μM and 100 μM Pb acetate. The results showed that Pb levels in blood and brain of Pb exposed groups were significantly higher than that of the control group (p < 0.05). The expression of HMGB1 and HO-1 were increased in Pb exposed groups than that of the control group (p < 0.05). Moreover, we found that the up-regulation of HO-1 in Pb exposure environment inhibited the expression of HMGB1. Copyright © 2018 Elsevier B.V. All rights reserved.

  5. Alluvial and riparian soils as major sources of lead exposure in young children in the Philippines: the role of floods.

    Science.gov (United States)

    Ostrea, Enrique M; Ostrea, Angelo M; Villanueva-Uy, Ma Esterlita; Chiodo, Lisa; Janisse, James

    2015-04-01

    The objective of this paper was to determine the prevalence and sources of high lead (Pb) exposure among children in Bulacan, Philippines. A total of 150 children (6-7 years old) and their caregivers were studied. Lead was analyzed in children hair and deciduous teeth. Sources of lead exposure were determined by caregiver interview and Pb analysis of house soil, drinking faucet water, air, and water from seven Bulacan rivers. Lead was positive in 91.3% of children's hair (MC or median concentration = 8.9 μg/g; range = 0-38.29), in 46.2% of the teeth (MC = 0.000 μg/mg in positive samples; range = 0.00-0.020), in 100% of soil (MC = 27.06 mg/kg; range = 3.05-1155.80), in 21.1% of air (MC = 0 μg/Ncm; range = 0-0.10), in 4% of house, faucet water (MC = 0.0 ppm; range = 0-40). There was a significant correlation (Spearman's rho) between Pb in children's hair and soil (r = 0.195; p = 0.017) and between Pb in house water and outdoor air (r = 0.616; p = 0.005). There is no significant correlation between Pb in children's hair and teeth. None of the potential sources of Pb from interview were related to lead exposure in the children. Water from seven Bulacan rivers was 100% positive for lead (MC = 70.00 ppb; range = 30-90). Widespread flooding with river overflow occurred in Bulacan in 2009 which likely caused lead contamination of the soil. There was no significant difference in the lead concentration of the soil whether near or far from the river (p = 0.205, Mann-Whitney U test). High lead exposure in children in Bulacan is likely from soil contaminated by lead-polluted rivers during flooding. In areas where flooding is common, alluvial and riparian soils from polluted rivers are important sources of lead exposure in children.

  6. Lead exposure in the general population of the Metropolitan Area of Barcelona. Blood levels and related factors

    Energy Technology Data Exchange (ETDEWEB)

    Sole, E. [Pediatrics Service, Hospital Universitari Arnau de Vilanova, Lleida (Spain); Ballabriga, A.; Dominguez, C. [Centre d`Investigacions en Bioquimica y Biologia Molecular, Vall d`Hebron Hospitals, School of Medicine, Pediatrics Department, Universitat Autonoma de Barcelona, Barcelona (Spain)

    1998-12-11

    A cross-sectional was conducted on 254 individuals not occupationally exposed to lead to determine the degree of lead exposure in the general population of the Metropolitan Area of Barcelona. Blood lead levels (BPb) were analysed by atomic absorption spectrophotometry and zinc protoporphyrin (ZPP) by haemofluorimetry. Blood lead levels were analysed with respect to individuals` age, sex, area of residence, the season of the year the blood was drawn and ZPP. Mean blood lead in our series was 0.22{+-}0.011 {mu}mol/l (mean{+-}S.E.); no significant differences were found with respect to area of residence, sex or season. A linear relationship was observed between BPb and individuals` age (BPb=0.08+0.05xage; r=0.37). The prevalence of lead intoxication (BPb>0.48 {mu}mol/l) was 7.1%. No linear relationship was observed between BPb and ZPP. ZPP determination does not appear to be a good screening method for lead intoxication since it presents low specificity and sensitivity values with an area below the ROC curve similar to the null value line (area below the curve=0.5052, IC 95%=0.443-0.568). We conclude that lead exposure does not constitute a serious health problem in the area studied, since BPb levels found are far below the toxic limit and the prevalence of intoxication is similar to that reported in other studies conducted in other developed countries

  7. Low-level exposure to organophosphate pesticides leads to restrictive lung dysfunction.

    Science.gov (United States)

    Peiris-John, Roshini Janet; Ruberu, Dawala Kusuma; Wickremasinghe, Ananda Rajitha; van-der-Hoek, Wim

    2005-10-01

    Apart from symptomology, there are very few reports on lung function following exposure to low levels of organophosphate (OP) pesticides in man. Twenty-five occupationally exposed farmers and 22 environmentally exposed freshwater fishermen were evaluated between and during OP spray seasons. Forty marine fishermen living away from agricultural areas were recruited as a control group. Forced vital capacity (FVC) and forced expiratory volume in the first second (FEV(1)) were measured by spirometry. Haemoglobin corrected erythrocyte acetylcholinesterase (AChE) levels were measured during and between (baseline estimation) spray seasons using a portable WHO-approved Test-mate system (EQM Research, Ohio). FVC ratio was lower in the farmers as compared to the controls (P<0.001) between exposure seasons. In the farmers, FVC ratio decreased further during the exposure season (P=0.023). FEV(1) was lower in the farmers as compared to the controls in both periods (P<0.05). In the fishermen, the decrease in ratios of FVC and FEV(1) following exposure to pesticides was not significant. FEV(1)/FVC ratios were similar in the three groups between (P=0.988) and during (P=0.159) exposure periods. Following exposure to OPs, AChE levels dropped 12.75% in the farmers (P<0.001) and 5.62% in the freshwater fishermen (P=0.001). Occupational exposure to OP results in restrictive lung dysfunction, a phenomenon not observed following environmental exposure.

  8. Development and performance test results of 50 kA vapor-cooled current lead for ITER

    International Nuclear Information System (INIS)

    Sugimoto, Makoto; Isono, Takaaki; Hamada, Kazuya

    1998-01-01

    JAERI has developed 50 kA current leads for the International Thermonuclear Experimental Reactor (ITER). The Center Solenoid (CS) Model Coil program is under way by means of international collaboration in ITER-EDA. The CS model coil is being developed for ITER CS coil and is for demonstration for ITER construction. The performance test of the CS model coil will be carried out at the JAERI ITER common test facility (CTF). The current lead consists of the vertical lead and the connection lead. The vertical lead is a vapor-cooled type and has a cable-in-conduit geometry. The vertical lead was designed with a heat leak of 1.2 W/kA at a helium flow rate of 0.06 g/(s·kA). The measured heat leak satisfied the designed value. The connection lead was made from copper pipe soldered with NbTi superconducting wires. The pipe was stabilized by the superconducting wires and a cooling channel. The current lead was operated up to 60 kA. The design and the performance test results of 50 kA current leads are reported. The results meet the specifications for the CS model coil test and for the ITER real machine. (author)

  9. Tooth Matrix Analysis for Biomonitoring of Organic Chemical Exposure: Current Status, Challenges, and Opportunities

    Science.gov (United States)

    Andra, Syam S.; Austin, Christine; Arora, Manish

    2015-01-01

    Epidemiological evidence supports associations between prenatal exposure to environmental organic chemicals and childhood health impairments. Unlike the common choice of biological matrices such as urine and blood that can be limited by short half-lives for some chemicals, teeth provide a stable repository for chemicals with half-life in the order of decades. Given the potential of the tooth bio-matrix to study long-term exposures to environmental organic chemicals in human biomonitoring programs, it is important to be aware of possible pitfalls and potential opportunities to improve on the current analytical method for tooth organics analysis. We critically review previous results of studies of this topic. The major drawbacks and challenges in currently practiced concepts and analytical methods in utilizing tooth bio-matrix are (i) no consideration of external (from outer surface) or internal contamination (from micro odontoblast processes), (ii) the misleading assumption that whole ground teeth represent prenatal exposures (latest formed dentine is lipid rich and therefore would absorb and accumulate more organic chemicals), (iii) reverse causality in exposure assessment due to whole ground teeth, and (iv) teeth are a precious bio-matrix and grinding them raises ethical concerns about appropriate use of a very limited resource in exposure biology and epidemiology studies. These can be overcome by addressing the important limitations and possible improvements with the analytical approach associated at each of the following steps (i) tooth sample preparation to retain exposure timing, (ii) organics extraction and pre-concentration to detect ultra-trace levels of analytes, (iii) chromatography separation, (iv) mass spectrometric detection to detect multi-class organics simultaneously, and (v) method validation, especially to exclude chance findings. To highlight the proposed improvements we present findings from a pilot study that utilizes tooth matrix biomarkers to

  10. Are the current Australian sun exposure guidelines effective in maintaining adequate levels of 25-hydroxyvitamin D?

    Science.gov (United States)

    Kimlin, Michael; Sun, Jiandong; Sinclair, Craig; Heward, Sue; Hill, Jane; Dunstone, Kimberley; Brodie, Alison

    2016-01-01

    An adequate vitamin D status, as measured by serum 25-hydroxyvitamin D (25(OH)D) concentration, is important in humans for maintenance of healthy bones and muscle function. Serum 25(OH)D concentration was assessed in participants from Melbourne, Australia (37.81S, 144.96E), who were provided with the current Australian guidelines on sun exposure for 25(OH)D adequacy (25(OH)D ≥50 nmol/L). Participants were interviewed in February (summer, n=104) and August (winter, n=99) of 2013. Serum 25(OH)D concentration was examined as a function of measures of sun exposure and sun protection habits with control of key characteristics such as dietary intake of vitamin D, body mass index (BMI) and skin colour, that may modify this relationship. The mean 25(OH)D concentration in participants who complied with the current sun exposure guidelines was 67.3 nmol/L in summer and 41.9 nmol/L in winter. At the end of the study, 69.3% of participants who complied with the summer sun exposure guidelines were 25(OH)D adequate, while only 27.6% of participants who complied with the winter sun exposure guidelines were 25(OH)D adequate at the end of the study. The results suggest that the current Australian guidelines for sun exposure for 25(OH)D adequacy are effective for most in summer and ineffective for most in winter. This article is part of a Special Issue entitled '17th Vitamin D Workshop'. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. The decline in kidney function with chromium exposure is exacerbated with co-exposure to lead and cadmium.

    Science.gov (United States)

    Tsai, Tsung-Lin; Kuo, Chin-Chi; Pan, Wen-Harn; Chung, Yu-Teh; Chen, Chiu-Ying; Wu, Trong-Neng; Wang, Shu-Li

    2017-09-01

    Environmental factors contribute significantly to the pathogenesis of chronic kidney disease. However, these factors, and particularly the toxic effects of heavy metals, have not been completely evaluated. Chromium is a widespread industrial contaminant that has been linked to nephrotoxicity in animal and occupational population studies. Nevertheless, its role in population renal health and its potential interactions with other nephrotoxic metals, such as lead and cadmium, remain unknown. We assessed the association between exposure to chromium, lead, and cadmium with renal function using estimated glomerular filtration rate (eGFR) in an analysis of 360 Taiwanese adults aged 19-84 years from the National Nutrition and Health Survey in Taiwan (2005-2008). Doubling of urinary chromium or lead decreased the eGFR by -5.99 mL/min/1.73 m 2 (95% confidence interval -9.70, -2.27) and -6.61 (-9.71, -3.51), respectively, after adjusting for age, sex, body mass index, hypertension, diabetes, cigarette smoking, sodium intake, education, urinary volume, and other metals. For those in the highest tertile of cadmium exposure, the eGFR decreased by -12.68 mL/min/1.73 m 2 (95% confidence interval -20.44, -4.93) and -11.22 mL/min/1.73 m 2 (-17.01, -5.44), as urinary chromium or lead levels doubled, respectively. Thus, there is a significant and independent association between chromium exposure and decreased renal function. Furthermore, co-exposure to chromium with lead and cadmium is potentially associated with additional decline in the glomerular filtration rate in Taiwanese adults. Copyright © 2017 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.

  12. The Relationship between Occupational Exposure to Lead and Hearing Loss in a Cross-Sectional Survey of Iranian Workers.

    Science.gov (United States)

    Ghiasvand, Masoumeh; Mohammadi, Saber; Roth, Brett; Ranjbar, Mostafa

    2016-01-01

    Ototoxic effect of exposure to lead has been reported by many researchers. This study was undertaken with a view to investigate the relationship between blood lead level (BLL) and hearing loss in workers in a lead-acid battery manufacturing plant in Tehran, Iran. In a cross-sectional study, 609 male workers were recruited from different locations in the factory. Association between BLL and hearing loss in different frequencies were measured. Relationships were analyzed by logistic regressions. Statistical significance was defined as p-value workers with mean age 40 ± 7 years and mean noise exposure level of 80 (75-85) dB were evaluated. BLLs were categorized into four quartiles, and hearing loss in each quartile was compared to the first one. In our regression models, BLL was associated significantly with high frequency hearing loss, adjusted odds ratios for the comparison of the fourth, third, and second quartiles to the first one are respectively: 3.98 (95% CI: 1.63-9.71, p hearing loss, after adjusting for potential confounders (age, body mass index, work duration, smoking, and occupational noise exposure) in logistic regressions. It is concluded that periodic hearing assessment by pure tone audiometry in workers exposed to lead should be recommended. However, additional studies are required to clarify the mechanisms of lead ototoxicity.

  13. Increase in the amount of erythrocyte delta-aminolevulinic acid dehydratase in workers with moderate lead exposure

    International Nuclear Information System (INIS)

    Fujita, H.; Sano, S.

    1982-01-01

    The amount of ALA-D in human erythrocytes was determined directly by radioimmunoassay or calculated from the restored activity assayed in the presence of zinc and dithiothreitol, and a good correlation was observed between the RIA-based and the restored activity-based amounts. The RIA-based amount of ALA-D in the blood of 10 normal individuals (blood lead levels of 5.6 +- 2.3 μg/100 ml: mean +- SD) and 19 lead-exposed workers (blood lead levels of 41.2 +- 10.2 μg/100 ml) was 54.1 +- 11.8 μg/ml blood and 92.3 +- 20.6 μg/ml blood, respectively, indicating an apparent increase of the enzyme amount in lead-exposed workers. A significant increase in the amount of erythrocyte ALA-D calculated from the restored activity in lead-exposed workers was observed even in the low blood lead level of 10-20 μg/100 ml, resulting in the range of blood lead level 20-40 μg/100 ml. No significant difference was observed in hematocrit and hemoglobin content between lead-exposed and non-exposed groups. These observations suggested that the increase of erythrocyte ALA-D in lead exposure was not due to anemia, which might result in the increase of young erythrocytes in peripheral blood. This increase in the amount of ALA-D in human erythrocytes might be a result of the function to overcome the inhibition of the enzyme in bone marrow cells during lead exposure, and these findings may throw light on the danger to human health of low-level lead toxicity. (orig.)

  14. Implications for wildlife and humans of dietary exposure to lead from fragments of lead rifle bullets in deer shot in the UK

    International Nuclear Information System (INIS)

    Knott, Jeff; Gilbert, Jo; Hoccom, David G.; Green, Rhys E.

    2010-01-01

    Lead poisoning caused by ingested spent lead shotgun pellets has long been known to be a cause of unnecessary mortality in waterfowl and has led to legislation limiting its use in many countries. Recent evidence has shown that the problem extends to terrestrial ecosystems and to fragmented rifle bullets eaten by scavengers as well as shotgun pellets. Dietary exposure of human consumers to lead from spent ammunition in game meat also poses potential risks to human health. To assess the degree of fragmentation of lead bullets used to kill wild deer, twelve deer were shot in the thorax using copper-jacketed lead-cored bullets, as part of planned deer management operations. The thoracic region of the eviscerated carcasses and the abdominal viscera of each deer were X-rayed. An average of 356 metal fragments was visible on radiographs of the carcass and 180 fragments in the viscera. The weight of fragments was estimated by reference to an X-rayed scale of fragments of known weight. The average total weight of metal fragments, likely to be mostly lead, was estimated to be 1.2 g for the carcass and 0.2 g for the viscera. The total estimated weight of fragments in the entire carcass was estimated to be 17% of the weight of the bullet. Most fragments were small in size, with those in the viscera being smaller than those in the carcass. Metal fragments in the viscera were sufficiently small that at least 80% of the metallic bullet-derived lead in the viscera would be expected to be ingested by scavenging birds, such as buzzards and eagles, which feed on them.

  15. Implications for wildlife and humans of dietary exposure to lead from fragments of lead rifle bullets in deer shot in the UK

    Energy Technology Data Exchange (ETDEWEB)

    Knott, Jeff, E-mail: jeff.knott@rspb.org.uk [Royal Society for the Protection of Birds, The Lodge, Sandy, Bedfordshire SG19 2DL (United Kingdom); Gilbert, Jo; Hoccom, David G. [Royal Society for the Protection of Birds, The Lodge, Sandy, Bedfordshire SG19 2DL (United Kingdom); Green, Rhys E. [Royal Society for the Protection of Birds, The Lodge, Sandy, Bedfordshire SG19 2DL (United Kingdom); Conservation Science Group, Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ (United Kingdom)

    2010-12-01

    Lead poisoning caused by ingested spent lead shotgun pellets has long been known to be a cause of unnecessary mortality in waterfowl and has led to legislation limiting its use in many countries. Recent evidence has shown that the problem extends to terrestrial ecosystems and to fragmented rifle bullets eaten by scavengers as well as shotgun pellets. Dietary exposure of human consumers to lead from spent ammunition in game meat also poses potential risks to human health. To assess the degree of fragmentation of lead bullets used to kill wild deer, twelve deer were shot in the thorax using copper-jacketed lead-cored bullets, as part of planned deer management operations. The thoracic region of the eviscerated carcasses and the abdominal viscera of each deer were X-rayed. An average of 356 metal fragments was visible on radiographs of the carcass and 180 fragments in the viscera. The weight of fragments was estimated by reference to an X-rayed scale of fragments of known weight. The average total weight of metal fragments, likely to be mostly lead, was estimated to be 1.2 g for the carcass and 0.2 g for the viscera. The total estimated weight of fragments in the entire carcass was estimated to be 17% of the weight of the bullet. Most fragments were small in size, with those in the viscera being smaller than those in the carcass. Metal fragments in the viscera were sufficiently small that at least 80% of the metallic bullet-derived lead in the viscera would be expected to be ingested by scavenging birds, such as buzzards and eagles, which feed on them.

  16. Exposure assessment in Beijing, China: biological agents, ultrafine particles, and lead.

    Science.gov (United States)

    Dong, Shuofei; Yao, Maosheng

    2010-11-01

    poor correlations between those in airborne and dust-borne states (R2=0.002~0.43). In our study, the lowest ultrafine particle concentration about 5,203 pt/cm3 was observed in office and the highest was observed at the train station, up to 32,783 pt/cm3. Lead concentration was shown to range from 80 to 170 ng/mg with the highest also observed at the train station. The information provided in this work can be used to learn the general situation of relevant health risks in Beijing. And the results here suggested that when characterizing exposure both airborne and dust-borne as well as the environments should be considered.

  17. Exposure to lead and cadmium released from ceramics and glassware intended to come into contact with food.

    Science.gov (United States)

    Rebeniak, Małgorzata; Wojciechowska-Mazurek, Maria; Mania, Monika; Szynal, Tomasz; Strzelecka, Agnieszka; Starska, Krystyna

    2014-01-01

    The dietary intake of harmful elements, particularly lead and cadmium constitutes a health threat and essential measures should be undertaken to reduce consumer exposure. The latest risk assessments by the European Food Safety Authority (EFSA) and Joint FAO/WHO Expert Committee on Food Additives (JECFA) have indicated that the Provisional Tolerable Weekly Intake (PTWI) for lead and cadmium do not ensure health safety and their review had to be undertaken. Migration from ceramics and glassware intended for food contact is an important source of lead and cadmium intake. To study the release of lead and cadmium from ceramics and glassware (including decorated products) intended for food contact that are available on the Polish market and to assess the resulting health risk to the consumer. Ceramics and glassware (mainly decorated) were sampled from the Polish market during 2010- 2012 throughout the country by staff of the Sanitary-Epidemiological Stations in accordance with monitoring procedures and guidelines designed by the National Institute of Public Health-National Institute of Hygiene. Migration of lead and cadmium was measured by incubating the samples with 4% acetic acid for 24 hours at a temperature of 22±2ºC in the dark. Flame Atomic Absorption Spectrometry (FAAS) was used to measure these elements in food simulant according to a validated and accredited method (PN-EN ISO/IEC 17025). 1273 samples of ceramics and glass wares were analysed in 2010-2012. Lead and cadmium release were usually found to be below analytical detection limits. Permissible migration limits (as prescribed by the legislation) of these metals were rarely exceeded and were reported mainly in articles imported from outside the EU. Two imported and decorated ceramic flat plates released lead at 0.9 and 11.9 mg/dm2 (limit 0.8 mg/dm2) and 5 imported deep plates gave migration values of 4.7 mg/L, 4.9 mg/L, 5.6 mg/L, 6.1 mg/L, 8.6 mg/L (limit 4.0 mg/L). Lead migrations from ceramic ware rims

  18. Environmental and Occupational Lead Exposure Among Children in Cairo, Egypt: A Community-Based Cross-Sectional Study.

    Science.gov (United States)

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

    2016-03-01

    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.

  19. Fetal alcohol exposure leads to abnormal olfactory bulb development and impaired odor discrimination in adult mice

    NARCIS (Netherlands)

    K.G. Akers (Katherine); S.A. Kushner (Steven); A.T. Leslie (Ana); L. Clarke (Laura); D. van der Kooy (Derek); J.P. Lerch (Jason); P.W. Frankland (Paul)

    2011-01-01

    textabstractBackground: Children whose mothers consumed alcohol during pregnancy exhibit widespread brain abnormalities and a complex array of behavioral disturbances. Here, we used a mouse model of fetal alcohol exposure to investigate relationships between brain abnormalities and specific

  20. Dietary exposure to cadmium, lead and nickel among students from the south-east region of Poland

    Directory of Open Access Journals (Sweden)

    Zbigniew Marzec

    2014-11-01

    Full Text Available Dietary intake of cadmium, lead and nickel was determined among students from three universities in Lublin to assess the levels of exposure to these contaminants compared to PTWI and TDI values. The study was performed in 2006–2010 and involved 850 daily food rations of students from the south–east region of Poland. The technique of 24-hour dietary recall and diet duplicates was used. Cadmium, lead and nickel complexes with ammonium-pyrrolidindithiocarbamate were formed and extracted to the organic phase with 4-methylpentan-2-one – MIBK in which their content was measured by flame atomic absorption spectrometry. The highest intake of the elements studied was observed in 2008. The data show that in none of the cases, the level of intake reached 70 % of PTWI/TDI values and thus the risk of developing diseases related to high exposure to these toxic metals absorbed from foodstuffs was low. The parameters of methods were checked during determinations by adding standard solutions to the samples before mineralization and by using two reference materials: Total diet ARC/CL HDP and Bovine muscle RM NIST 8414. The dietary exposure to lead and cadmium has significantly decreased in recent years whereas the exposures to nickel remain on stable levels.

  1. Brain cancer associated with environmental lead exposure: evidence from implementation of a National Petrol-Lead Phase-Out Program (PLPOP) in Taiwan between 1979 and 2007.

    Science.gov (United States)

    Wu, Wei-Te; Lin, Yu-Jen; Liou, Saou-Hsing; Yang, Chun-Yuh; Cheng, Kuang-Fu; Tsai, Perng-Jy; Wu, Trong-Neng

    2012-04-01

    In 1981, a Petrol-Lead Phase-Out Program (PLPOP) was launched in Taiwan for the abatement of environmental lead emissions. The present study was intended to examine whether the high Petrol-Lead Emission Areas (PLEA) would result in an increase in the incidence rate of brain cancer based on a national data bank. The national brain cancer incidence data was obtained from the Taiwan National Cancer Registry. Age standardized incidence rates were calculated based on the 2000 WHO world standard population, and gasoline consumption data was obtained from the Bureau of Energy. The differences in the trend tests for age-standardized incidence rates of brain cancer between high, median, low, and small PLEA were analyzed. A significant increase was found from small to high PLEA in age-standardized incidence rates of brain cancer. By taking six possible confounders into account, the age-standardized incidence rates for brain cancer were highly correlated with the median and high PLEA by reference to the small PLEA. After being adjusted for a number of relevant confounders, it could be concluded that high PLEA might result in an increase in the incidence rate of brain cancer resulting from high lead exposures. Copyright © 2011 Elsevier Ltd. All rights reserved.

  2. Risk of single and combined exposure of birds to non-steroidal anti-inflammatory drugs and lead.

    Science.gov (United States)

    Osickova, Jitka; Skochova, Hana; Ondracek, Karel; Kral, Jiri; Damkova, Veronika; Peckova, Lucie; Pohanka, Miroslav; Vitula, Frantisek; Bandouchova, Hana; Pikula, Jiri

    2012-01-01

    Pharmaceuticals and heavy metals such as diclofenac and lead, respectively, have been identified as environmental contaminants toxic to birds and posing serious threats to declining populations of raptors worldwide. The aim of the present study was to test the hypothesis that a sublethal combination of non-steroidal anti-inflammatory drugs and lead induces more pronounced effects than single exposures in birds. A total of 40 Japanese quails (Coturnix coturnix japonica) at the age of 2 months and average weight of 180g were on a random basis divided into four experimental groups of 10 specimens (i.e., control, diclofenac, lead, and lead+diclofenac exposures). Six lead shots in the total weight of 1.5 grams were inserted into the crop on day 0 of the experiment, while a total of 5 mg/kg of diclofenac administered intramuscularly were divided into treatments on days 0 and 5. Group responses were compared using haematology and biochemistry after 10 days. There was no mortality in control and both single and combined diclofenac and lead exposure groups, nor did the birds show any clinical signs of intoxication. Univariate analyses of blood parameters yielded a decrease in haematocrit in birds exposed to both substances when compared with the control, a lower haemoglobin level of the lead-exposed group, increased activity of aspartate aminotransferase in the NSAIDs-exposed group, increased activity of alkaline phosphatase in birds exposed to a combination of diclofenac and lead, and a higher phosphorus level in the lead-exposed group. The principal component analysis revealed no multivariate pattern of responses of blood parameters and did not allow separation of exposure groups from controls when the variables and samples were projected onto a two dimensional space. Results of the present study can enhance understanding of combination toxicity of veterinary drugs and heavy metals in birds, i.e. a scenario that has become environmentally relevant in recent decades

  3. House dust as possible route of environmental exposure to cadmium and lead in the adult general population

    International Nuclear Information System (INIS)

    Hogervorst, Janneke; Plusquin, Michelle; Vangronsveld, Jaco; Nawrot, Tim; Cuypers, Ann; Van Hecke, Etienne; Roels, Harry A.; Carleer, Robert; Staessen, Jan A.

    2007-01-01

    Contaminated soil particles and food are established routes of exposure. We investigated the relations between biomarkers of exposure to cadmium and lead, and the metal loading rates in house dust in the adult residents of an area with a soil cadmium concentration of >=3mg/kg (n=268) and a reference area (n=205). We determined the metal concentrations in house dust allowed to settle for 3 months in Petri dishes placed in the participants' bedrooms. The continuously distributed vegetable index was the first principal component derived from the metal concentrations in six different vegetables. The biomarkers of exposure (blood cadmium 9.2 vs. 6.2nmol/L; 24-h urinary cadmium 10.5 vs. 7.0nmol; blood lead 0.31 vs. 0.24μmol/L), the loading rates of cadmium and lead in house dust (0.29 vs. 0.12 and 7.52 vs. 3.62ng/cm 2 /92 days), and the vegetable indexes (0.31 vs. -0.44 and 0.13 vs. -0.29 standardized units) were significantly higher in the contaminated area. A two-fold increase in the metal loading rate in house dust was associated with increases (P<0.001) in blood cadmium (+2.3%), 24-h urinary cadmium (+3.0%), and blood lead (+2.0%), independent of the vegetable index and other covariates. The estimated effect sizes on the biomarkers of internal exposure were three times greater for house dust than vegetables. In conclusion, in the adult population, house dust is potentially an important route of exposure to heavy metals in areas with contaminated soils, and should be incorporated in the assessment of health risks

  4. Current man-made mineral fibers (MMMF) exposures among ontario construction workers.

    Science.gov (United States)

    Verma, Dave K; Sahai, Dru; Kurtz, Lawrence A; Finkelstein, Murray M

    2004-05-01

    Current occupational exposures to man-made mineral fibers (MMMF), including refractory ceramic fibers (RCF), were measured as part of an exposure assessment program for an epidemiological study pertaining to cancer and mortality patterns of Ontario construction workers. The assessments were carried out at commercial and residential sites. A total of 130 MMMF samples (104 personal and 26 area) was collected and included 21 RCF (16 personal and 5 area). The samples were analyzed by the World Health Organization method in which both respirable and nonrespirable airborne fibers are counted. The results show that Ontario construction workers' full-shift exposure to MMMF (excluding RCF) is generally lower than the American Conference of Governmental Industrial Hygienists' (ACGIH) recommended threshold limit value-time-weighted average (TLV-TWA) of 1 fibers/cc and thus should not present any significant hazard. However, approximately 40% of the occupational exposures to RCF are higher than ACGIH's TLV-TWA of 0.2 fibers/cc and present a significant potential hazard. Workers generally wore adequate approved respiratory protection, especially while performing particularly dusty tasks such as blowing, spraying, and cutting, so the actual exposure received by workers was lower than the reported values. Adequate control measures such as ventilation and respiratory protection should always be used when work involves RCF.

  5. Current Problems and Possible Solutions in High-Temperature Lead-Free Soldering

    Czech Academy of Sciences Publication Activity Database

    Kroupa, Aleš; Andersson, D.; Hoo, N.; Pearce, J.; Watson, A.; Dinsdale, A.; Mucklejohn, S.

    2012-01-01

    Roč. 21, č. 5 (2012), s. 629-637 ISSN 1059-9495 Institutional support: RVO:68081723 Keywords : lead-free soldering, * materials for high-temperature LF * new technologies for HT lead-free soldering Subject RIV: BJ - Thermodynamics Impact factor: 0.915, year: 2012

  6. Occupational exposure and biological evaluation of lead in Iranian workers-a systematic review and meta-analysis

    Directory of Open Access Journals (Sweden)

    Kourosh Sayehmiri

    2016-09-01

    Full Text Available Introduction: Lead exposure is considered as a global health problem. The irreparable harmful effects of this heavy metal on human have been proven in various studies. Comparing to general population, workers in related industries are more exposed to lead. Several studies have investigated lead occupational exposure and its biological evaluation in Iran; however there is no overall estimate. Thus, the present study was conducted to determine the occupational exposure to lead and its biological evaluation in Iranian workers, using systematic review and meta-analysis. Material and Method: This study was carried out based on information obtained from databases including Magiran, Iranmedex, SID, Medlib, Trials Register, Scopus, Pubmed, Science Direct, Cochran, Embase, Medline, Web of Science, Springer, Online Library Wiley, and Google Scholar from 1991 to 2016, using standard key words. All of the reviewed papers which met the inclusion criteria have been evaluated. Data combination was performed according to Random Effects Model using Stata software version 11.1. Result: In the 34 qualified studies, the mean blood lead level (BLL concentration in Iranian workers was estimated 42.8µg/dl (95% CI: 35.15-50.49. The minimum and maximum BLL were belonged to west (28.348µg/dl and center (45.928µg/dl regions of Iran, respectively. Considering different occupations, the lowest mean value was reported in textile industry workers (12.3 µg/dl, while the highest value was for zinc-lead mine workers (72.6 µg/dl. Mean breathing air lead level of Iranian workers reported in 4 studies was estimated 0.23 mg/m3 (95% CI: 0.14-0.33. Conclusion: According to the high concentration of BLL and breathing air, it is recommended to increase protective measures and frequent screening. Scheduled clinical and paraclinical examination should also be performed for workers.

  7. General population exposure of stable lead and 210Pb to residents of New York City

    International Nuclear Information System (INIS)

    Bogen, D.C.; Welford, G.A.; Morse, R.

    1975-12-01

    Stable lead and