• Title/Summary/Keyword: Lead

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Experimental Studies on Lead Toxicity in Domestic Cats 1. Symptomatology and Diagnostic Laboratory Parameters (고양이의 납중독에 관한 실험적 연구 1. 임상증상 및 실험실적 평가)

  • Hong Soon-Ho;Han Hong-Ryul
    • Journal of Veterinary Clinics
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    • v.10 no.1
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    • pp.111-130
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    • 1993
  • Lead toxicity was evaluated in forty-five cats on a balanced diet, Treated with 0(control), 10, 100(low), 1, 000, 2, 000, and 4, 000(high) ppm of lead acetate orally on a body weight basis. The objectives were to establish toxic dosage level of leaf in cats, to characterize changes in behavior and clinical pathology, and to demonstrate what blood lead concentrations correlate with the known dosages of lead. Some high dose cats showed projectile vomiting, hyperactivity, and seizures. The growth rates did not appear to be altered in any of the dosed groups. Normal blood lead concentration in cats were lower than that of humans, dogs, and cattle. Blood lead concentrations of 3 to 20$\mu\textrm{g}$/100$m\ell$ could be termed a 'subclinical' range in the cat. Clinical lead toxicity in cats may have blood lead concentrations ranging 20 to 120$\mu\textrm{g}$/100$m\ell$. Zinc protoporphyrin concentrations were proportional to lead dosages and a significant ZPP elevation, greater than 50$\mu\textrm{g}$/100$m\ell$, may be indicative of clinical lead toxicity. The enzyme aminolevulinic acid dehydratase showed an inverss dose response relationship for all lead dosages and a significant ZPP elevation, greater than 50$\mu\textrm{g}$/100$m\ell$, may be indicative of clinical lead toxicity. The enzyme aminolevulinic acid dehydratase showed an inverse dose response relationship for all lead dosages and appears to be a good indicator of lead exposure in cats. Urinary aminolevuliruc acid concentrations generally increased with lead dosage, but individual values varied. Hair lead concentrations rose proportionately to lead dosages. Lead at least in high doses appears to inhibit chemotactic activity of polymorphonuclear cells and monocytes. No consistent dose response relationships were observed in hemoglobin, RBC, WBC, neutrophil, lymphocyte, monocyte, and eosinophil counts. There were no consistent dose related changes in total protein, plasma protein, BUN, and ALT values. Reticulocyte counts did not increase significantly in most lead dosage levels, and are probably of little value in diagnosing lead toxicity in cats. The fact that no significant changes were found in nerve conduction velocities may support that there was no segmental demyelination resulting from lead ingestion. The lethal dose in cats appear to range from 60 to 150mg/kg body weight. A reliable diagnosis of lead poisoning can be made utilizing blood lead, ZPP, and ALAD, and hair lead.

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MRP System with Emergent Lead Time (긴급선행기간을 이용한 MRP 시스템)

  • Nam, Sun-Hee;Yun, Won-Young
    • IE interfaces
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    • v.4 no.1
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    • pp.47-61
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    • 1991
  • This paper develops MRP system with two-types of lead time(average lead time and emergent lead time). In this proposed MRP system, Material Requirement Planning is scheduled by using average lead time, but the emergent lead time is used only when start date of planned order is past. Btrieve data management technique and Stack structure are used for recalculating procedure of planned order with the TURBO PASCAL Version 5.5. An example is also considered.

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Study on The Preventive Structure of field Lead Connector's V-Notch on Synchronic (동기발전기 회전자 계자접속부의 예각변형 방지구조에 관한 연구)

  • Cho, Ji-Won;Cho, Chang-Joo
    • Proceedings of the KIEE Conference
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    • 2000.07b
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    • pp.937-939
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    • 2000
  • The preventive structure of field lead connector's V-notch on synchronous generator has been developed. The preventive structure of field lead, installed in the generator, prevent from V notch of field lead connector in rotor on daily start and stop (on-line). This development of study was performed at the Seoinchon combined cycle power plant on gas turbine generator. This preventive structure of field lead will be prevent from V-notch of field lead on synchronous generator's field.

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Iron deficiency increases blood concentrations of neurotoxic metals in children

  • Kim, Yangho;Park, Sangkyu
    • Clinical and Experimental Pediatrics
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    • v.57 no.8
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    • pp.345-350
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    • 2014
  • Iron deficiency affects approximately one-third of the world's population, occurring most frequently in children aged 6 months to 3 years. Mechanisms of iron absorption are similar to those of other divalent metals, particularly manganese, lead, and cadmium, and a diet deficient in iron can lead to excess absorption of manganese, lead, and cadmium. Iron deficiency may lead to cognitive impairments resulting from the deficiency itself or from increased metal concentrations caused by the deficiency. Iron deficiency combined with increased manganese or lead concentrations may further affect neurodevelopment. We recently showed that blood manganese and lead concentrations are elevated among iron-deficient infants. Increased blood manganese and lead levels are likely associated with prolonged breast-feeding, which is also a risk factor for iron deficiency. Thus, babies who are breast-fed for prolonged periods should be given plain, iron-fortified cereals or other good sources of dietary iron.

기능성기를 지닌 고분자 자성체를 이용한 수용액 중 납이온 추출

  • 서형석;최규찬;나인욱;황경엽
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2004.04a
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    • pp.175-176
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    • 2004
  • To develope of efficient method for decontaminating of lead ions from industrial wastewater, treatment of aqueous lead solution with magnetic beads was investigated. Immobilization of carboxyl groups on tile surface of magnetic beads was carried out to introduce chelate effect between lead ions and beads. Experiments were performed with lead solutions and magnetic beads at pH 6. Lead ions were extracted during 1 hour, After extraction, magnetic beads were separated from water by outer magnetic force and the solution was analysed by atomic absorption spectroscopy (AAS). Over 90 % of lead ions could be removed from aqueous solution after beads application. This result indicate that magnetic beads can be used as a efficient method for removing lead ions from industrial wastewater.

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Non-destructive Analysis of Bronze Bell in the Heungguksa Temple (흥국사 동종의 비파괴 조사 분석)

  • Hong, Jong-Ouk;Lee, Jea-Jin
    • 보존과학연구
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    • s.31
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    • pp.131-140
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    • 2010
  • This study shows the comparison of chemical compositions of main component with other bronze bells after the research on the component analysis by non-destructive XRF analysis. There are shrinkage cavities caused by the shrinkage defect and pores with pollutants on Bronze Bell of Heungguksa Temple with gamma radiation images and 77.3% of copper, 8.4% of tin and 10.9% of lead were determined as the main components of it with XRF analysis The tin content of Brozen Bell of Heungguksa Temple is less than those (11~18%) of other bronze bells but the lead content of that is higher. The lead content of it shows 10.91% which is quite high while generally the lead contents of other bells were controlled lower than 2.1%. Buddhist bells have the different lead content according to the period. The lead content was low until Silla Dynasty and Unified Silla period but it has been getting higher since some point of Koryo Dynasty. It is assumed that expensive copper and tin were replaced with lead.

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Plasma Membrane Transporters for Lead and Cadmium

  • Bressler Joseph P.;Olivi Luisa;Cheong Jae Hoon;Kim Yongbae;Bannon Desmond
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 2004.11a
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    • pp.50-61
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    • 2004
  • Lead and cadmium are potent environmental toxicants that affect populations living in Europe, Americas, and Asia. Identifying transporters for lead and cadmium could potentially 1 help us better understand possible risk factors. The iron transporter divalent metal transporter 1(DMT1) mediates intestinal transport of cadmium, and lead in yeast and fibroblasts overexpressing DMT1. In human intestinal cells knocking down expression of DMT1 attenuated uptake of cadmium and iron but not lead. A possible explanation is the expression of a second transporter for lead in intestine. In astrocytes, however, DMT1 appears to transport lead in an extracellular buffer at pH value. At neutral pH, transport was not mediated by DMT1 but rather by a transporter that is stimulated by bicarbonate and inhibited by 4,4'-diisothiocyanatodihydrostilbene-2,2'-disulfonic acid. The identity of this lead transporter is under study.

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A Study on the Correlation between Lead in Airborne Suspended Particulates and Leaves of Roadside Trees in Urban Area (대기부유분진중 Pb와 가로수잎중 Pb와의 상관성에 관한 연구)

  • 고현규;김희강;현용범
    • Journal of Korean Society for Atmospheric Environment
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    • v.2 no.3
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    • pp.11-18
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    • 1986
  • In order to evaluate the state of the environmental pollution by vehicle exhaust in Seoul area the correlation between lead in air and leaves of roadside trees has been investigated during August in 1985. The dust in the atmosphere was collected by high volume air sampler to measure the concentration of lead. On the other hand, lead as a pollution indicator was extracted from the leaves of roadside trees (Ginkgo biloba, Salix pseudo/lasiogyne, platanus occidentalis) by conventional method and their concentrations were determined. The following results were obtained : 1. Lead concentrations in the leaves of roadside trees varied with trees, for example, the average concentrations of lead in each of the leaves of Ginkgo biloba, Salix pseudo/lasiogyne and Platanus occidentalis were 20.66 ppm, 9.37 ppm, and 10.58 ppm, respectively. 2. The dust sampled along heavily traveled highways showed that lead content tended to increase with traffic volume. 3. The correlation coefficients between lead correlation in air and leaves of Gingo biloba, Salix pseudo/lasiogyne, and Platanus orientalis were 0.80, 0.85, and 0.87, respectively.

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Blood Lead Level of Families and Environmental Factors (가족 구성원의 혈중 납농도에 영향을 미치는 환경요소)

  • 민경복;민진영;조성일;백도명
    • Proceedings of the Korean Environmental Health Society Conference
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    • 2002.04a
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    • pp.60-63
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    • 2002
  • Objectives : To estimate the correlation of blood lead level of families and environmental factors and infer its influence on blood lead levels in the Korean urban area in Seoul Korea. Methods : The study subjects comprised 499 men and 489 women from 366 families and we analyzed the blood lead level using induced coupled plasma/mass spectroscopy and had interviews. Results : The mean blood lead level of men was 3.00 $\mu\textrm{g}$/dL. The stastical analysis of this study used the tool of frequency rate and t-test between blood lead levels of families and environmental factors. Especially father's smoking and dusty workplace environment showed significancy to blood lead levels. Conclusion : There was positive relationship of blood lead level to several environmental factors. These facts show outdoor environment is more influential than home environment.

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On Lead Contamination of Roadside Trees in Jinju City (진주시 가로수의 연(Pb) 오염에 관하여)

  • 성민웅
    • Journal of Plant Biology
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    • v.19 no.4
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    • pp.107-110
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    • 1976
  • This study was carried out to investigate lead contamination in the leaves of roadside trees and the cause of yellow-brown symptom of leaves in Jinju and Daegu city. After the leaves were collected and dried in 105$^{\circ}C$ drying oven from September to October in 1974, the samples were used for analysis of the lead contents in 1976. The roadside trees in the two cities were mostly the four kinds of Ginkgo biloba L., Thuja orientalis L., Platanus orientalis L. var. acerifolia AIT. and Prunus pseudo-cerasus $LINDL{\times}Prunus$ subhirtella MIQ. The lead contents in the leaves of roadside trees in Daegu city was higher than that of Jinju city. The lead contamination of the evergreen trees of roadside was higher than that of the deciduous trees. In Jinju city the site of the highest contents of lead in the leaves was revealed with Jinju station(0.73ppm), the next site was revealed with the road(0.16ppm) between Namgang bridge and Jinju middle school, and the lowest site was generally beside the roads of suburbs (0.07ppm). Because of the low contents of lead in the leaves, it was found that the yellow-brown symptoms of leaves were not caused by the lead toxicity.

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