Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “LEAD”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 595 records · Page 33Linked to original sources
PubMed1999

Blood lead levels in emergency department patients with retained lead bullets and shrapnel.

OBJECTIVE: To determine whether patients with retained lead shrapnel who present to the ED have elevated whole blood lead levels (BLLs) compared with matched control patients. METHODS: Test subjects were patients with x-ray evidence of retained lead shrapnel who presented to any of three urban EDs, and consented to inclusion in the study. BLLs were obtained from 15 ED patients, and data regarding time since injury and symptoms of plumbism were collected. Control subjects consisted of 15 ED patients, without similar lead exposure, matched for age, sex, race, and place of dwelling as determined by zip code, who also presented to any of the same three EDs. RESULTS: The mean (+/-SD) BLL in the test subjects was 17+/-9.78 microg/dL (range 7-50 microg/dL). Time since impalement ranged from 1 to 45 years. The mean BLL in the control subjects was 7+/-3.77 microg/dL (0-16 microg/dL). This difference was statistically significant (two-tailed t-test p = 0.002). CONCLUSIONS: In this preliminary study, the patients with retained lead shrapnel who presented to the ED had significantly elevated BLLs, compared with the matched control subjects. Chronic plumbism may be considered in patients with retained lead shrapnel, and a history should be taken to assess the presence of symptoms referable to plumbism. These patients may require long-term follow-up to assess the development of elevated blood lead level and lead toxicity.

Adult↗
PubMed1983

Subjective symptoms after long term lead exposure in secondary lead smelting workers.

The prevalence of lead induced subjective symptoms was evaluated by a standardised questionnaire in a group of 96 workers employed between nine and 45 years in a secondary lead smelting works. A control group of 96 non-lead exposed subjects, matched for age and sex, were chosen from the Glostrup population study. Blood lead concentrations were in excess of 60 micrograms/100 ml in about 30% of the lead workers. Zinc protoporphyrin levels were found to be higher than 500 mumol/Hb in nearly 18% of the lead workers. The prevalence of fatigue, headache, sleep disturbance, and digestive symptoms (constipation and colic) were not higher in the lead exposed group. The body weight showed no significant difference in the two groups. Nervousness was four times more frequent in the control group. The results indicate that subjective symptoms are useless as indicators of incipient lead poisoning.

Adult↗
PubMed2000

Safety and efficacy of succimer in toddlers with blood lead levels of 20-44 microg/dL. Treatment of Lead-Exposed Children (TLC) Trial Group.

Although lead encephalopathy has virtually disappeared from the United States, thousands of children still have sufficient lead exposure to produce cognitive impairment. It is not known whether treating children with blood lead levels < 45 microg/dL (2.2 microM) is beneficial and can be done with acceptable safety. We conducted a 780-child, placebo-controlled, randomized trial of up to three courses of succimer in children with blood lead levels of 20-44 microg/dL (1.0-2.1 microM). Children were aged 12-33 mo, 77% were African-American, 7% were Hispanic, and they lived in deteriorating inner city housing. Placebo-treated children had a gradual decrease in blood lead level. Succimer-treated children had an abrupt drop in blood lead level, followed by rebound. The mean blood lead level of the succimer-treated children during the 6 mo after initiation of treatment was 4.5 microg/dL (95% confidence intervals, 3.7 to 5.3 microg/dL; 0.22 microM, 0.18 to 0.26 microM) lower than that of placebo-treated children. There were more scalp rashes in succimer-treated children (3.5% versus 1.3%) and an unanticipated excess of trauma. Succimer lowers blood lead level with few side effects. The unanticipated excess of trauma requires confirmation.

Chelating Agents↗
PubMed1990

Determinants of elevated blood lead during pregnancy in a population surrounding a lead smelter in Kosovo, Yugoslavia.

We are prospectively examining the relation between environmental lead exposure and pregnancy outcome in cohorts of women exposed to a wide range of air lead concentrations. Titova Mitrovica, Yugoslavia, is the site of a large lead smelter, refinery, and battery factory. At midpregnancy, 602 women in T. Mitrovica and 900 women in Pristina, a non-lead-exposed control town, were interviewed. Blood was obtained for blood lead (PbB), hemoglobin, erythrocyte protoporphyrin, and serum ferritin measurements. Women were seen again at delivery, at which time maternal and umbilical cord blood samples were obtained. While many demographic and social characteristics were similar across the two towns, women in Pristina were more likely to report employment outside the home, cigarette smoking, and alcohol use during pregnancy. As expected, PbB levels were substantially higher in the smelter town. At midpregnancy, PbB geometric means were 17.1 micrograms/dL in T. Mitrovica and 5.1 micrograms/dL in Pristina; 86% of the pregnant women in T. Mitrovica, compared to 3.4% of those in Pristina, had PbB levels greater than 10 micrograms/dL. Within T. Mitrovica, distance between the home and the smelter was the most important predictor of PbB at mid-pregnancy and delivery. Husband's employment in the lead industry was associated with a significant increase in maternal PbB levels independent of place of residence. Higher maternal serum ferritin concentrations were associated with lower PbB levels, suggesting that dietary iron inhibits lead absorption. Overall, the placenta was a poor barrier to lead; the relationship between maternal PbB and umbilical cord PbB was linear across a wide range of PbB levels.

Adult↗
PubMed2002

Correlations of blood lead with DNA-protein cross-links and sister chromatid exchanges in lead workers.

Levels of sister chromatid exchanges (SCEs), high-SCE frequency cells (HFCs), DNA-protein cross-links (DPCs), blood lead (BLL), and zinc protoporphyrin (ZPP) were measured in peripheral blood from three groups. The lead workers were divided into two groups: a high BLL group (> or =15 microg/dl) and a low BLL group (<15 microg/dl). The control subjects were selected from an area that had not been contaminated with lead and had normal BLL and ZPP levels. In addition, exposure to airborne lead was measured for 11 lead workers, and the time-weighted average was shown to range from 0.19 to 10.32 mg/m(3). The BLL levels of 9 of 11 workers were >15 microg/dl, of which, 3 exceeded current exposure limits (> or =40 microg/dl). The BLL levels of all 11 controls were < 15 microg/dl. The average SCE and DPC values for the workers were 6.1 SCEs/cell and 1.9%, which were significantly higher (P < 0.01, Wilcoxon's test) than the value of 5.2 SCEs/cell and 1.1% for the control subjects. Lead workers had significantly higher BLL and ZPP levels than did the controls. Statistically significant increases in DPCs, SCEs, and HFCs were observed for the high-BLL group compared with the control group. The results of this study suggest that DPCs, SCEs, and HFCs are reliable biomarkers for monitoring workers exposed to lead and clearly indicate health effects from occupational exposure to lead.

Adult↗
PubMed1976

Lead content of tissues of baby rats born of, and nourished by lead-poisoned mothers.

Three groups of Wistar rats (5 males and 5 females in each group) were given zero, 100 mg., and 200 mg. Pb(NO3) 2 per kilogram of body weight per day for 45 days and were mated. The lead feeding was continued throughout the duration of experiments. The blood and urinary lead, blood aminolevulinic acid dehydratase activity, and free erythrocyte protoporphyrin and urinary aminolevulinic acid were measured on these rats at the beginning of the study, at the time of mating, and prior to delivery. The tissues, incuding kidney, liver, heart, and brain of the newborn progeny were analyzed for lead content. The blood lead and aminolevulinic acid dehydratase were also measured (pooled blood). These tissues contained very high amounts of lead when the newborns were killed within half an hour after their birth, a very significant reduction being found after one day with further reduction after 7 days. Kidney and heart contained the highest amount of lead, the levels being dose-related. Three weeks after birth the lead content of tissues rose significantly but blood concentrations remained almost identical to the levels obtained 1 day after birth. There was no evidence of lead accumulation in the brain of the babies...

Aminolevulinic Acid↗
PubMed1994

Experimental model of lead nephropathy. IV. Correlation between renal functional changes and hematological indices of lead toxicity.

Adverse effects on hematopoiesis and renal function have been reported in both animals and humans exposed to high doses of lead for a protracted period of time, but little is known about the interrelationship between these two target organ systems. The present study examines rats exposed via drinking water to high dose (5000 mg/L) or low dose (100 mg/L) lead, either continuously or discontinuously, for periods ranging from 1 to 12 months. In addition to blood lead, indices of hematological abnormalities included hematocrit, zinc protoporphyrin (ZPP) and red blood cell (RBC) membrane sodium-potassium-activated adenosine triphosphatase (Na-K-ATPase). Renal function abnormalities were assessed by measurements of glomerular filtration rate (GFR) by the single injection 125-I-iothalamate technique and urinary excretion of the proximal renal tubular enzyme, ligandin. Blood lead and GFR correlated positively during the first 6 months of lead administration, reflecting a stimulatory effect of lead on renal hypertrophy and GFR during this time period. When this distorting effect was factored out, there were few residual correlations between renal and hematological abnormalities. The only significant relationship between GFR and hematological parameters of lead toxicity was a negative correlation between GFR and RBC membrane Na-K-ATPase in animals treated with high dose lead for 6 months and observed at the end of 12 months (discontinuous group).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1994

Screening for chronic lead poisoning in lead factory workers.

One hundred and forty-nine lead factory workers comprising of 46 fume exposed, 78 handling lead materials and 25 controls were screened for chronic lead poisoning. Blood lead level was determined by atomic absorption spectrometery and urinary ALA by ion-exchange chromatography. Fume exposed workers had significantly higher (P < 0.01) blood lead (median 61.20 micrograms/dl, range 21.20-171.10 micrograms/dl) and urinary ALA levels (median 4.10 mg/l, range 01.0-22.9 mg/l) than workers handling lead materials and controls. Urinary ALA was found to be a more sensitive and specific test for lead poisoning than estimation of blood lead levels.

Adult↗
PubMed1993

[Lead in drinking water--determination of a new limit value and the problem of lead pipes].

The problem of lead in drinking water with regard to sensitive groups of the general population (e.g. unborn, babies that are not breast-fed, infants and children) is discussed. In respect of children in nurseries, the question regarding the relation of blood-lead levels to neurobehavioural deficits due to lead as well as a theoretical "tolerable" daily intake of lead is discussed. A provisional daily intake of approx. 1.2-1.3 micrograms Pb/kg body weight for children and pregnant women is proposed. For non-pregnant adults a double to three times higher intake may be tolerated (base: high blood pressure). These doses are well three times below the still recognised Provisional Tolerable Weekly Intake of led (PTWI-values, WHO), when related to daily intake. Considering the water consumption as well as the proportionate share of other exposure routes which result in the total lead exposure of risk groups, a toxicologically tolerable level of 10 micrograms Pb/l in drinking water is suggested. A reduction of the actual limiting value in drinking water (40 micrograms Pb/l) is advised. A special problem arises from lead tubes within the water distribution system. Water in stagnation as well as in use in these tubes may have enhanced lead concentrations. Therefore, it is recommended to exchange lead tubes preferentially in areas of sensitive use (e.g. as in the kitchen).

Adult↗
PubMed1996

Identification of children at risk for lead poisoning: an evaluation of routine pediatric blood lead screening in an HMO-insured population.

OBJECTIVES: To estimate the prevalence of elevated blood lead levels in children receiving well-care checkups; and to evaluate the effectiveness of certain key risk factors in detecting children at higher risk for elevated blood lead levels. DESIGN: Cross-sectional study. SETTING: Two facilities of the Kaiser Permanente Medical Care Program (KPMCP) health maintenance organization (HMO), northern California region. PATIENTS: Six hundred thirty-six children, aged 12 to 60 months, who were seen at four KPMCP facilities in two subregions for a well-care checkup from September 1991 through August 1992. INTERVENTIONS: Blood samples were collected from each child and analyzed for lead content. Participating parents completed a questionnaire that included questions recommended by the Centers for Disease Control and Prevention (CDC) about the child's and the parents' lead exposure via home, workplace, and hobbies. RESULTS: Ninety-six percent of the children had blood lead levels under 10 micrograms/dL. Blood lead levels declined with increasing age and were higher for black children compared with whites. Age of residential housing, mother's education, and residence in an old house with peeling paint had low sensitivity and positive predictive value for identifying children with blood lead levels over 10 micrograms/dL. CONCLUSION: Universal routine screening for elevated blood lead levels in children in an employed, HMO-insured population is not warranted on grounds of prevalence. Responses to CDC questions do not effectively identify high-risk children in this population.

Child, Preschool↗
PubMed2000

Cancer mortality study of employees at lead battery plants and lead smelters, 1947-1995.

BACKGROUND: This study has examined cancer mortality of a cohort of male U.S. workers exposed to lead. METHODS: The cohort consisted of 4,518 workers at lead battery plants and 2,300 at lead smelters. Vital status was ascertained between 1947 and 1995. Site-specific cancer standardized mortality ratios (SMRs) and 95% confidence intervals (95% CIs), based on the mortality rates of the U.S. male population and adjusted for age and calendar time, were calculated for the total cohort as well as subcohorts stratified by various exposure parameters. In addition, a nested case-control study of stomach cancer (30 cases and 120 age-matched controls) was also conducted. RESULTS: Mortality from all cancers was as expected (897 observed deaths, SMR = 103.8, 95% CI: 97.1-110.8). Mortality was significantly raised for stomach cancer (SMR = 147.4, 95% CI: 112. 5-189.8), lung cancer (SMR = 116.4, 95% CI: 103.9-129.9), and cancer of the thyroid and other endocrine glands (SMR = 308.0, 95% CI: 133. 0-606.8). There was a nonsignificant mortality deficit from kidney cancer (SMR = 63.6, 95% CI: 33.9-108.7). For bladder cancer, mortality was significantly lower than expected (SMR = 55.5, 95% CI: 31.7-90.1). Nonsignificant mortality deficits were also reported for cancer of the central nervous system (SMR = 74.8, 95% CI: 41.9-123. 4) and lymphatic and hematopoietic cancer (SMR = 92.2, 95% CI: 72. 4-115.7). Additional analyses by type of facility (lead battery plants vs. lead smelters), length of employment, latency, and period of hire were also performed. In the nested case-control study of stomach cancer, odds ratios were calculated for various exposure indices, and none was found to be elevated. Furthermore, no exposure-response relationship between lead exposure and stomach cancer was found in the nested case-control study. CONCLUSIONS: A significant mortality increase from stomach cancer was found. However, based on the analyses in the cohort study and the nested case-control study, the increase did not appear to be related to lead exposure. A small, but statistically significant mortality increase from lung cancer was also observed. The small increase, in the absence of an exposure-response relationship, could be the result of confounding due to smoking, and was not likely causally related to lead exposure. Although the significant increase in cancer of the thyroid and other endocrine glands appeared to be consistent with an occupational interpretation, the small number of deaths (8), the lack of information on potential confounding factors, and the lack of reporting of a similar increase in other studies underscore the need to view this finding with caution. No increased mortality was found for kidney cancer, bladder cancer, cancer of the central nervous system, or lymphatic and hematopoietic cancer.

Case-Control Studies↗
PubMed2000

Environmental lead exposure in a population of children in northern France: factors affecting lead burden.

BACKGROUND: This study is part of the assessment of a site in northern France polluted by lead from industrial emissions. Our objectives were to look for the factors that influence lead burden in children aged 8-11 years. METHODS: A cross-sectional population-based study took place in 1996-97 and included 400 children (200 of whom lived on the metal-polluted site). RESULTS: The geometric mean of the blood-lead levels of children living on the polluted site was 39.5 microg/l (95% CI = 36.3-43.1); that of the non-exposed children was 30.6 microg/l (95% CI = 27.8-33.6) (P < 0.0001). Analysis of the variations in the mean blood-lead levels showed associations with: distance from the smelting plants (mean blood-lead level fell by a factor of 1/1.3 (95% CI = 1/1.2-1/1.4) for each km from the smelter over the range of 1-3 km and was constant thereafter) and consumption of tap water (when the water pipes were made of lead, the mean blood-lead level of children who drank tap water was twice as high (95% CI = 1.2-3.4) as that of children who did not). CONCLUSIONS: The children's blood-lead levels were essentially linked to two factors: proximity to the smelters and drinking tap rather than bottled water.

Body Burden↗
PubMed2004

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

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

Environmental Monitoring↗
PubMed1976

[Lead content of vegetable foods in vicinity of lead emitting industry].

By means of atomic absorption spectrophotometry, the authors determined the lead content in vegetable, fruit and soil samples from the environments of a lead-smelting plant. The lead values obtained were some 10- to 100-fold higher than those found normally. The mean lead content in vegetables varied from 2 to 150 p.p.m. in dry matter; that in fruits, from 4 to 35 p.p.m. Lead concentrations ranging from 575 to 2900 p.p.m. were detected in the soil samples. The mean lead content in the atmosphere was between 0.62 and 0.95 mug/m3 (maximum value 12 mug/m3). From these data it was calculated that the total resorption of lead from vegetables, fruits, potatoes and air varied from 0.04 to 0.49 mg/day in the territory under investigation. To protect the population against increased intake of lead, it is recommended to abandon individual and commercial vegetable and fruit growing, especially leaf vegetables. Since the contamination of the soil persists for generations, the authors discuss its replacement by non-contaminated surface soil.

Air Pollution↗
PubMed1996

Transfer of lead from lead-glazed ceramics to food.

Recent studies have shown a clear correlation between the use of lead-glazed ceramicware for cooking or food preparation and elevated blood lead levels. Two lots of lead-glazed ceramic bowls, each from a single manufacturing and firing lot were used to measure the sequential leaching of lead into salsa (an acidic food) and beans (a neutral food) stored or cooked in the bowls. The USFDA acetic acid extraction assay was also repeatedly performed on these bowls. The results of the USFDA extraction test were highly variable with levels ranging from 200 to more than 2,000 ppm (regulatory level for rejection is 2 ppm). The levels extracted declined rapidly but the rates were variable. Leaching of lead into salsa (pH = 4.8) was variable and ranged from 8 to greater than 500 ppm. Sequential extractions using salsa yielded variable but declining lead levels. Cooking beans with water in the bowls did not cause substantial leaching (levels between 3 and 8 ppm) and sequential cooking did not show any significant decline over 10 cycles. The results indicate substantial variability in leaching of lead into foods stored or cooked in lead-glazed ceramicware.

Acids↗
PubMed1981

Evaluation of studies of the relationship between blood lead and air lead.

An evaluation of the major studies of the effects of airborne lead on blood lead levels of male and female adult and child populations is presented. Analysis of these studies shows that the blood lead-air lead slope for adults is approximately 1.0 for both men and women. This implies that an exposure to an additional 1 microgram Pb/m3 of air can result in an increase of approximately 1 microgram Pb/100 ml of blood. The precision of the slope for adults is rarely better than +/- 0.5 to +/- 0.7 and can be as large as +/- 1.0. A large portion of this uncertainty in the calculated slope is due to blood lead measurement error. The slope of the blood lead-air lead response for children ranges from 0.7 to 1.4 and is approximately the same as that for adults. The accuracy of this number is less clear for children than adults due to the small data base. Many of the studies of children have been on populations living in the vicinity of smelters. It is questioned whether these data are representative of the air lead exposure of children living in urban and suburban communities.

Air Pollutants↗
PubMed2004

Portable lead analyzer to locate source of lead.

OBJECTIVE: To investigate the sources of lead in the environment in children with elevated blood, with the help of a Field Portable X-Ray Fluorescence Analyzer. METHODS: One hundred and seven school children were chosen for this study on a random basis, from Mangalore and Karnataka. Their blood lead was analyzed. Of the cases analyzed, 10 students whose blood lead level was more than 40 microg/dl were investigated using a field portable X-Ray Fluorescence Analyzer. This is the first time such a device has been available for this purpose in India. RESULTS: The 'likely' source of lead exposure could be determined in eight cases which was from the immediate environment of the children like 'lead-based' paint on surfaces in the house, on playground and other exterior equipment; lead storage batteries, contaminated dust and soil and other lead-containing substances. CONCLUSION: The use of an X-Ray Fluorescence Analyser appeared to be useful in determining the source of lead.

Child↗
PubMed1987

Effects of lead in the laboratory mouse. Development and social behaviour after lifelong exposure to 12 microM lead in drinking fluid.

The effects of chronic exposure to 12 microM lead, from conception onwards, on development and social behaviour were investigated in the laboratory mouse. Lead was administered as 0.25% solution of lead acetate in the drinking fluid. This level of exposure did not affect reproductive success, but caused decreased birthweight and retarded early development in offspring of treated dams. Mortality prior to weaning was significantly greater in pups treated with lead, and animals treated with lead had significantly reduced body weights throughout their lives. Levels of lead in tissues were greatly increased in all treated animals, with females showing significantly higher levels than males. Behaviour was assessed by ethological methods in paired encounters between unfamiliar animals in a novel environment. At age 3-4 weeks Exploratory Behaviour and Social Investigation were significantly increased and Immobility was significantly decreased in animals of both sexes treated with lead. Social Investigation was also increased at age 7-8 weeks but Exploratory Behaviour was decreased. At age 15-16 weeks Non-Social Activity was increased in males and decreased in females, although Social and Sexual Investigation was not affected in these male-female encounters. Lead-treated males, aged 17-18 weeks, showed significantly shorter latencies to aggression towards unfamiliar males than did controls.

Administration, Oral↗