Note: This page contains sample records for the topic urine lead concentration from Science.gov.
While these samples are representative of the content of Science.gov,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of Science.gov
to obtain the most current and comprehensive results.
Last update: November 12, 2013.
1

Pelvic urine composition as a determinant of inner medullary solute concentration and urine osmolarity  

Microsoft Academic Search

To clarify the question whether solute and water fluxes between pelvic urine and the renal papilla contribute to the medullary accumulation of osmotically active substances and thus to final urine concentration, we measured the osmolarity of urine samples from the papillary tip of rat kidneys during superfusion of the exposed papillae with solutions of widely varying osmotic concentrations. When the

W. Schütz; J. Schnermann

1972-01-01

2

Urine nickel concentrations in nickel-exposed workers.  

PubMed

Electrothermal atomic absorption spectrometry was employed for analyses of nickel concentrations in urine samples from nickel-exposed workers in 10 occupational groups and from non-exposed workers in two control groups. Mean concentrations of nickel in urine were greatest in workers who were exposed to inhalation of aerosols of soluble nickel salts (e.g., workers in nickel plating operations and in an electrolytic nickel refinery). Less marked increases in urine nickel concentrations were found in groups of metal sprayers, nickel battery workers, bench mechanics and are welders. No significant increases in mean concentrations of nickel were found in urine samples from workers who performed grinding, buffing and polishing of nickel-containing alloys or workers in a coal gasification plant who employed Raney nickel as a hydrogenation catalyst. Measurements of nickel concentrations in urine are more sensitive and practical than measurements of serum nickel concentrations for evaluation of nickel exposures in industrial workers. PMID:655606

Bernacki, E J; Parsons, G E; Roy, B R; Mikac-Devic, M; Kennedy, C D; Sunderman, F W

3

Uranium associations with kidney outcomes vary by urine concentration adjustment method.  

PubMed

Uranium is a ubiquitous metal that is nephrotoxic at high doses. Few epidemiologic studies have examined the kidney filtration impact of chronic environmental exposure. In 684 lead workers environmentally exposed to uranium, multiple linear regression was used to examine associations of uranium measured in a 4-h urine collection with measured creatinine clearance, serum creatinine- and cystatin-C-based estimated glomerular filtration rates, and N-acetyl-?-D-glucosaminidase (NAG). Three methods were utilized, in separate models, to adjust uranium levels for urine concentration-?g uranium/g creatinine; ?g uranium/l and urine creatinine as separate covariates; and ?g uranium/4?h. Median urine uranium levels were 0.07??g/g creatinine and 0.02??g/4?h and were highly correlated (rs=0.95). After adjustment, higher ln-urine uranium was associated with lower measured creatinine clearance and higher NAG in models that used urine creatinine to adjust for urine concentration but not in models that used total uranium excreted (?g/4?h). These results suggest that, in some instances, associations between urine toxicants and kidney outcomes may be statistical, due to the use of urine creatinine in both exposure and outcome metrics, rather than nephrotoxic. These findings support consideration of non-creatinine-based methods of adjustment for urine concentration in nephrotoxicant research.Journal of Exposure Science and Environmental Epidemiology advance online publication, 17 April 2013; doi:10.1038/jes.2013.18. PMID:23591699

Shelley, Rebecca; Kim, Nam-Soo; Parsons, Patrick J; Lee, Byung-Kook; Agnew, Jacqueline; Jaar, Bernard G; Steuerwald, Amy J; Matanoski, Genevieve; Fadrowski, Jeffrey; Schwartz, Brian S; Todd, Andrew C; Simon, David; Weaver, Virginia M

2013-04-17

4

Blood and urine catecholamine concentrations after implantation of artificial heart.  

PubMed

Plasma and urine epinephrine and norepinephrine concentrations were measured before and after implantation of an artificial heart in 20 calves and before and after thoracotomy in 3 control calves. All animals had similar preoperative plasma and urine catecholamine concentrations. During the first 4 postoperative days, plasma and urine epinephrine and norepinephrine concentrations were markedly elevated in all animals. However, calves with an artificial heart had significantly higher concentrations than control calves. Thereafter, catecholamine levels in control animals returned to preoperative levels, whereas epinephrine concentrations in artificial heart recipients remained elevated for 2 weeks and norepinephrine concentrations remained elevated for over a month. Two artifical heart recipeints survived longer than 2 months and had normal plasma and urine catecholamine concentrations from day 32 until a few days before being put to death. Although the mechanism in unclear, these findings suggest that early artificial heart function is associated with a significant metabolic stress which slowly disappears or becomes tolerable after one month. PMID:1263555

Stanley, T H; Kennard, L; Isern-Amaral, J; Olsen, D; Lunn, J

1976-05-01

5

The Mammalian Urine Concentrating Mechanism: Hypotheses and Uncertainties  

NSDL National Science Digital Library

The urine concentrating mechanism of the mammalian kidney, which can produce a urine that is substantially more concentrated than blood plasma during periods of water deprivation, is one of the enduring mysteries in traditional physiology. Owing to the complex lateral and axial relationships of tubules and vessels, in both the outer and inner medulla, the urine concentrating mechanism may only be fully understood in terms of the kidneyÃÂs three-dimensional functional architecture and its implications for preferential interactions among tubules and vessels.

Anita Layton (Duke University Mathematics); PhD William H. Dantzler (University of Arizona College of Medicine Department of Physiology)

2009-08-01

6

Urine and serum concentrations of inhaled and oral terbutaline.  

PubMed

We examined urine and serum concentrations after therapeutic use of single and repetitive doses of inhaled and supratherapeutic oral use of terbutaline. We compared the concentrations in 10 asthmatics and 10 healthy subjects in an open-label, cross-over study with 2 mg inhaled and 10 mg oral terbutaline on 2 study days. Further, 10 healthy subjects were administrated 1 mg inhaled terbutaline in 4 repetive doses with total 4 mg. Blood samples were collected at baseline and during 6 h after the first inhalations. Urine samples were collected at baseline and during 12 h after the first inhalations. Median (IQR) urine concentrations peaked in the period 0-4 h after inhalation with Cmax 472 (324) ng/mL in asthmatics and 661 (517) ng/mL in healthy subjects, and 4-8 h after oral use with Cmax 666 (877) ng/mL in asthmatic and 402 (663) ng/mL in healthy subjects. In conclusion we found no significant differences in urine and serum concentrations between asthmatic and healthy subjects. We compared urine and serum concentrations after therapeutic inhaled doses and supratherapeutic oral doses and observed significant statistical differences in both groups but found it impossible to distinguish between therapeutic and prohibited use based on doping tests with urine and blood samples. PMID:22782385

Elers, J; Hostrup, M; Pedersen, L; Henninge, J; Hemmersbach, P; Dalhoff, K; Backer, V

2012-07-10

7

Correlation between Amalgam Restorations and Mercury Concentrations in Urine  

Microsoft Academic Search

The creatinine-adjusted urinary concentration of mercury in 73 schoolchildren with a mean age of 12 years was determined. In addition, the number of amalgam restorations and their size, prevalence of allergy, and days absent from school due to illness were recorded for each individual. A significant positive correlation (r = 0.55) was found between urine Hg and extent of amalgam

M. L. Olstad; R. I. Holland; N. Wandel; A. Hensten Pettersen

1987-01-01

8

Elevated Urine Zinc Concentration Reduces the Detection of Methamphetamine, Cocaine, THC and Opiates in Urine by EMIT.  

PubMed

Methods for circumventing positive drug tests continue to evolve and are often spread through internet websites reporting on the proposed effectiveness of various adulteration methods. Recent claims of the use of zinc added directly to urine or ingested prior to urine collection have prompted investigation into the vulnerability of ELISA-based testing, providing interesting but inconclusive results. We investigated the potential interference of zinc used as a direct adulterant and after zinc self-administration for enzyme multiplied immunoassay technique (EMIT)-based drug abuse testing in urine. Negative urine samples and samples collected before and after zinc self-administration were fortified with d-methamphetamine, benzoylecgonine, morphine and 11-nor-9-carboxy-tetrahydrocannabinol prior to analysis by the EMIT. Our data indicate that zinc added directly to urine in concentrations 5,000 times higher than a typical random urine total zinc concentration is capable of producing false-negative results; however, self-administration of oral zinc was unable to generate random urine total zinc concentrations in the required range. Further, no evidence of a secondary interfering substance was observed as a result of oral zinc self-administration. Our results indicate that the total zinc concentrations required to directly interfere with EMIT-based testing are easily distinguishable from routine random urine total zinc concentrations, and that alleged oral ingestion of zinc does not produce total zinc concentrations capable of direct interference. PMID:23843421

Lin, Chia-Ni; Strathmann, Frederick G

2013-07-10

9

Urine concentration and dilution in hypokalemic and hypercalcemic dogs  

PubMed Central

The urine-concentrating mechanism was studied in chronic hypokalemia (seven dogs given a low K+, high NaCl diet plus injections of deoxycorticosterone acetate [DOCA]) and chronic hypercalcemia (seven dogs given vitamin D). In the potassium-depleted dogs, muscle, serum, and urine K+ fell markedly, but glomerular filtration rate (GFR) and body weight varied little. Maximum urine osmolality fell in all dogs (mean decrease = 45%); however, solute-free water reabsorption (TCH2O) at high rates of solute excretion remained normal in three of four dogs. Free water excretion (CH2O) increased normally or supranormally as a function of increasing Na+ delivery to Henle's loop in six dogs so tested. Hypercalcemia of several weeks duration caused a decrease in both GFR (mean 36%) as well as in maximum urine osmolality (mean 57%). Maximum TCH2O was not invariably depressed; in fact, when the values were adjusted for the reduced number of functioning nephrons (TCH2O/CIn), four of seven studies were normal. CH20/CIn increased normally (or supranormally) with increasing fractional Na delivery to Henle's loop in four of five dogs. I conclude that the lowered maximum urine osmolality in these hypokalemic and hypercalcemic dogs was not related to abnormal water reabsorption from the collecting ducts. Although not specifically measured in this study, it is very likely that solute accumulation in the renal medulla was reduced. This probably was not caused by abnormal delivery of sodium to, nor reabsorption of sodium from Henle's loop. It is likely that a more subtle defect exists in the countercurrent mechanisms for establishing a steep concentration gradient in the renal medulla. In the few hypercalcemic dogs in whom GFR was very low, I believe that injury to, and blockage of medullary tubules could account for most of the reduction in maximum UOsm. Although not specifically ruled out, there is no evidence here to suggest that high serum Ca+ or low serum K+ per se causes a defect in sodium and water reabsorption in the mammalian nephron.

Bennett, Cleaves M.

1970-01-01

10

Individual variability in human tibia lead concentration.  

PubMed Central

Our aims in this study were to determine proximal-distal variability in adult human tibia lead concentration via electrothermal atomization atomic absorption spectrometry (ETAAS) and to determine whether there were any differences between core and surface tibia lead concentrations. We analyzed duplicate core and surface tibia samples for lead at multiple proximal-distal sections on 10 adult human cadaver legs. Dried bone samples were digested in nitric acid using microwave-assisted heating, and lead content was determined by ETAAS with Zeeman background correction. Lead concentrations in nine tibiae (one tibia was excluded because some of the data were compromised) ranged from 3.1 to 27.9 microg lead/g of dry bone. Both core and surface tibia lead concentrations were lower at the proximal and distal ends of the tibia. Surface tibia lead was approximately 5 microg/g greater than core tibia lead in six tibiae with relatively low lead concentration, and 8 microg/g greater in three tibiae with relatively high lead concentration. The difference between core and surface tibia lead was independent of proximal-distal tibia location. We conclude that these nine human tibiae showed a greater surface tibia lead concentration than core tibia lead concentration. This observation has consequences for the noninvasive measurement of tibia lead via K-shell and L-shell X-ray fluorescence.

Todd, A C; Parsons, P J; Tang, S; Moshier, E L

2001-01-01

11

Determination of lead in blood and urine by SPME/GC.  

PubMed

Lead is the most frequently quantitated toxic metal in biological matrixes. In this paper, a method is described for lead determination in whole blood and urine using solid-phase microextraction (SPME) gas chromatography. Lead ion is first derivatized with sodium tetraethylborate to form tetraethyllead, which is then extracted from the headspace over the sample by SPME. The analytical procedure was optimized for coating selection, pH, extraction time, and effect of salt. The relative standard deviation was less then 10% for both urine and blood samples. The limit of detection was 3 and 4 ppb; the limit of quantification is 5 and 10 ppb for urine and blood samples, respectively. Good linearity was found for both urine and blood samples when PDMS coating was used. The standard addition method was used for quantitation. Certified urine and blood samples were analyzed, and good accuracy was obtained. PMID:10450149

Yu, X; Yuan, H; Górecki, T; Pawliszyn, J

1999-08-01

12

Urine Processing for Water Recovery via Freeze Concentration  

Microsoft Academic Search

Resource recovery, including that of urine water extraction, is one of the most crucial aspects of long-term life support in interplanetary space travel. This paper will consequently examine an innovative approach to processing raw, undiluted urine based on low-temperature freezing. This strategy is uniquely different from NASA's current emphasis on either 'integrated' (co-treatment of mixed urine, grey, and condensate waters)

Jeffrey M. Schmidt; James E. Alleman

2005-01-01

13

Plasma and Blood Lead Concentrations, Lead Absorption, and Lead Excretion in Nonhuman Primates  

Microsoft Academic Search

In order to assess the comparability of lead disposition in the cynomolgus monkey to that in the human, we determined the relationships among blood lead concentration, plasma lead concentration, and lead excretion in monkeys. Six adult (3–5 kg) female cynomolgus monkeys (Macaca fascicularis) without previous experimental lead exposure were given single intravenous injections of from 750 to 3300 ?g lead

E. J. O'Flaherty; M. J. Inskip; A. P. Yagminas; C. A. Franklin

1996-01-01

14

Blood lead concentrations and pregnancy outcomes.  

PubMed

In this study, the authors related blood lead concentrations to Apgar scores, birth weight, gestational age, small-for-gestational age, and hypertension in pregnancy (HIP)/toxemia. Data and blood were collected 4 times during pregnancy from 705 women, aged 12-34 yr. Blood lead concentrations, measured by atomic absorption spectrophotometry, were related to reproductive outcomes, abstracted from medical records. Average blood lead concentrations were 1.2 microgram/dl (standard error = +/- 0.03). Maternal blood lead concentrations were related significantly to HIP/toxemia--before and after adjusting for age, calcium intake, and race/ethnicity (p < .03). Longitudinal regression analyses revealed that blood lead concentrations in women with HIP/toxemia changed by 0.02 microgram/dl for every 0.01 microgram/dl change in women without HIP/toxemia. Maternal blood lead concentration and its change were not significantly associated with other reproductive outcomes. Low levels of maternal blood lead concentrations were significantly associated with HIP/toxemia. PMID:12641194

Sowers, MaryFran; Jannausch, Mary; Scholl, Theresa; Li, Wenjie; Kemp, Francis W; Bogden, John D

15

Tissue lead concentrations in Japanese quail ingesting lead Pellets or shot with lead pellets  

SciTech Connect

Data obtained from birds shot by hunters warrant the consideration that shooting with lead pellets may contrbute to the quantity of lead detected in tissues. Information on the effects of shooting avian species with lead shot on tissue concentrations of lead is, therefore, of considerable importance in assessing the value of birds shot by hunters as a source of samples for studying lead contamination. Kendall found that liver and bone lead concentrations of mourning doves were substantially increased after ingestion of a lead shot. Waterfowl shot by hunters and with direct evidence of ingested lead shot had significantly higher liver lead concentrations than did waterfowl without ingested lead shot. As little information on the effects of shooting with lead projectiles on tissue lead concentrations exists, the present study was designed to measure the effects of shooting Japanese quail (Coturnix coturnix japonica) with lead pellets on lead concentrations in livers and in bones).

Kendall, R.J.; Scanlon, P.F.

1981-05-01

16

Adult polycystic kidney disease: Studies of the defect in urine concentration  

Microsoft Academic Search

Adult polycystic kidney disease: Studies of the defect in urine concentration. Patients with adult polycystic kidney disease with and without renal insufficiency and some of their family members in whom cysts were not demonstrable by radiography underwent tests of maximal urine concentrating ability (Umax). Ten of the twelve family members without demonstrable cysts (Group I) had Umax exceeding 900 mOsm\\/kg.

Manuel Martinez-Maldonado; Jackson J Yium; Garabed Eknoyan; Wadi N Suki

1972-01-01

17

Elevated urine arsenic: un-speciated results lead to unnecessary concern and further evaluations.  

PubMed

The consumption of seafood within two to three days of testing can increase total urine arsenic concentrations. Few clinicians are familiar with this fact and often misinterpret elevated results. A retrospective chart review of all cases with arsenic testing seen between 1991 and 2004 at an occupational and environmental medicine referral clinic was performed. Urine arsenic results were classified as follows: total arsenic levels; speciated results (inorganic, ionic arsenic); and whether the patient abstained from seafood prior to the collection. Laboratory detection limits for total and for ionic arsenic were < or = 2 microg/L. Fifty-four patients with urine arsenic testing were identified. The total urine arsenic concentration exceeded 40 microg/L for 28 patients. On paired, speciated testing (n = 21), mean total arsenic was 122 +/- 227 microg/L, and ionic arsenic was not detected in any of these same samples (p = 0.023). On paired testing, before and after seafood abstention (n = 12), total urine arsenic without abstention was 291 +/- 267 microg/L, and it was only 9 +/- 12 microg/L after seafood abstention (p = 0.004). The total urine arsenic elevations observed in our series were due to benign organic arsenic compounds commonly found in seafood. Laboratories should reflexively perform speciation on most samples with elevated total arsenic concentrations prior to reporting the results. Reflexive speciation could reduce unnecessary referrals, further testing, and patient anxiety. PMID:16620536

Kales, Stefanos N; Huyck, Karen L; Goldman, Rose H

2006-03-01

18

Blood lead concentration after a shotgun accident.  

PubMed

In an accidental shooting, a man in his late forties was hit in his left shoulder region by about 60 lead pellets from a shotgun. He had injuries to the vessels, the clavicle, muscles, and nerves, with total paralysis of the left arm due to axonal injury. After several surgical revisions and temporary cover with split skin, reconstructive surgery was carried out 54 days after the accident. The brachial plexus was swollen, but the continuity of the nerve trunks was not broken (no neuroma present). We determined the blood lead (BPb) concentration during a follow-up period of 12 months. The BPb concentration increased considerably during the first months. Although 30 lead pellets were removed during the reconstructive surgery, the BPb concentration continued to rise, and reached a peak of 62 microg/dL (3.0 micromol/L) on day 81. Thereafter it started to decline. Twelve months after the accident, BPb had leveled off at about 30 microg/dL. At that time, muscle and sensory functions had partially recovered. The BPb concentration exceeded 30 microg/dL for 9 months, which may have influenced the recovery rate of nerve function. Subjects with a large number of lead pellets or fragments embedded in the body after shooting accidents should be followed for many years by regular determinations of BPb. To obtain a more stable basis for risk assessment, the BPb concentrations should be corrected for variations in the subject's hemoglobin concentration or erythrocyte volume fraction. PMID:11781173

Gerhardsson, Lars; Dahlin, Lars; Knebel, Richard; Schütz, Andrejs

2002-01-01

19

Concentration compared with total urinary excretion of 11,17-DOA in cynomolgus monkey urine.  

PubMed

Strees sensitive molecules exhibit great variation in concentration in the circulation and it may often be advantageous to quantify these in urine or feces rather than in serum or plasma. We advocate that all urine-or feces-should be collected, and that excretion of stress sensitive molecules should be expressed as amounts excreted per time unit per kg body-weight, rather than being expressed as concentrations in samples. Urine and feces excretion varies significantly within and between animals over time, which may render simple concentration measures of molecules of little biological relevance. PMID:19508615

Hau, Jann; Royo, F

2008-06-01

20

Serum and urine concentrations of trypsinogen-activation peptide as markers for acute pancreatitis in cats  

PubMed Central

The purpose of this study was to compare the clinical utility of the serum concentration of feline trypsin-like immunoreactivity (fTLI), the plasma and urine concentrations of trypsinogen-activation peptide (TAP), and the ratio of the urine TAP and creatinine concentrations (TAP:Cr) in the diagnosis of feline acute pancreatitis. We used 13 healthy cats and 10 cats with a diagnosis of acute pancreatitis. The mean serum fTLI and plasma TAP concentrations were significantly higher in the cats with acute pancreatitis than in the healthy cats (P < 0.05); the mean urine TAP concentrations and the median urine TAP:Cr ratios were not significantly different. Among the cats examined in this study, there was no benefit of plasma TAP over serum fTLI in the evaluation of suspected acute pancreatitis.

Allen, Heidi S.; Steiner, Jorg; Broussard, John; Mansfield, Caroline; Williams, David A.; Jones, Boyd

2006-01-01

21

Adjustment of Creatinine-Adjusted Value to Urine Flow Rate in Lead Workers  

Microsoft Academic Search

Two male lead workers, aged 57 and 51 y, were studied to compare the urinary flow\\/creatinine-adjusted values published earlier by Araki et al. and by Greenberg and Levine. We collected 24-h urine samples once a month for 31 mo and 16 mo for workers 1 and 2, respectively. The workers' urinary excretions of lead, delta-aminolevulinic acid, and coproporphyrin were measured.

Fumihiro Sata; Shunichi Araki

1996-01-01

22

Assessment of blood and urine lead levels of some pregnant women residing in Lagos, Nigeria  

Microsoft Academic Search

Assessment of lead in blood (BLL) and lead in urine (ULL) of some non-occupationally exposed, nonsmoking 214 pregnant Nigerian\\u000a women, aged 17 to 49 years, and resident in Lagos was carried out using atomic absorption spectrometry with control subjects\\u000a consisting of 113 nonpregnant women. From results, the mean BLL and ULL (?g\\/dL) for pregnant women (59.5 ± 2.1; 29.4 ± 1.1)

Iheoma M. Adekunle; Joseph A. Ogundele; Olusegun Oguntoke; Oluseyi A. Akinloye

2010-01-01

23

[A study of urine concentrating mechanism--a molecular biological approach].  

PubMed

Human urine can be concentrated up to four times higher than that of the plasma. Urine concentrating mechanism has attracted for a long time. However, studies in the field are now picking up momentum due to recent breakthrough discoveries using molecular biology techniques. Vasopressin-regulated water channel in the apical membrane of the collecting duct and water channel in the basolateral side of the membrane were cloned. cloned. Osmolality-dependent chloride channel in the thin ascending limb of Henle was also cloned. In addition, vasopressin-regulated urea transporter was found in the collecting duct. These newly discovered channels and transporter should be playing important physiological roles in urine concentrating mechanism. Furthermore, recent findings on osmolytes and their transporters also add to the list of urine concentrating mechanisms. PMID:8072215

Marumo, F

1994-07-01

24

Determining the normal concentration of uranium in urine and application of the data to its biokinetics  

SciTech Connect

A method was developed to determine the concentration of uranium (238U) in urine. This method involved preconcentration of uranium from urine with calcium phosphate neutron activation followed by simple radiochemical separation. Using this method, it was possible to detect 0.2 ng of 238U. The average and geometric mean concentration of uranium found in urine of subjects from a normal background environment was 12.8 and 9.4 ng L-1, respectively. The concentration of uranium in the urine and the daily intake of uranium by the same population was used to arrive at the gastrointestinal absorption factor (f1) for uranium incorporated in the diet. The f1 factor was estimated to be 1.6%.

Dang, H.S.; Pullat, V.R.; Pillai, K.C. (Health Physics Division, Bhabha Atomic Research Centre, Bombay (India))

1992-06-01

25

Relation between bloodand urine-amphetamine concentrations in impaired drivers as influenced by urinary pH and creatinine  

Microsoft Academic Search

Amphetamine undergoes extensive renal excretion and significant amounts are present in urine as the unchanged parent drug. This prompted us to investigate whether a quantitative relationship existed between blood and urine concentrations of amphetamine in the body fluids of drug-impaired drivers apprehended in Sweden, where this stimulant is the major drug of abuse. The relationship between blood and urine concentrations

A W Jones; L Karlsson

2005-01-01

26

Ion exchange chromatography as a selective pre-concentration method for PIXE analysis of urine  

NASA Astrophysics Data System (ADS)

A cation exchange resin, Chelex 100, has been used to separate and preconcentrate trace metal ions in urine. The separation from macro-elements is good and the concentration factor for trace metals is about 50. The detection limits are decreased by a factor between 20 and 40 compared to direct analysis of urine which enables the analysis of metals with low level of natural occurrence.

Pakarinen, Pirjo; Pallon, Jan; Akselsson, Roland

1984-04-01

27

Urine concentrations of ecgonine from specimens with low benzoylecgonine levels using a new ecgonine assay.  

PubMed

A new approach to detecting drug positives for cocaine in urine having benzoylecgonine concentrations below the Department of Defense (DoD) cutoffs was examined by measuring the concentrations of the metabolite ecgonine. The DoD cutoff concentrations for determining a positive for cocaine are 150 and 100 ng/mL for radioimmunoassay and gas chromatography-mass spectrometry, respectively. To facilitate this approach, a new assay was developed for ecgonine using only 1 mL urine. The urine was passed through an anion-exchange cartridge, and the eluant was evaporated to dryness in a water bath under nitrogen. The residue was subjected to nonylation and a standard back extraction procedure before a second derivatization with propionic anhydride. A total of 139 urine specimens were analyzed in this manner, and 104 yielded ecgonine concentrations greater than 50 ng/mL. The average ecgonine concentration in the latter specimens was approximately 5 times the comparable benzoylecgonine concentration. By monitoring ecgonine alone or in conjunction with benzoylecgonine, the number of cocaine positives detected in urine could be dramatically increased. PMID:7564289

Hornbeck, C L; Barton, K M; Czarny, R J

28

Concentrations of Phthalate Metabolites in Milk, Urine, Saliva, and Serum of Lactating North Carolina Women  

PubMed Central

Background Phthalates are ubiquitous in the environment, but concentrations in multiple media from breast-feeding U.S. women have not been evaluated. Objectives The objective of this study was to accurately measure and compare the concentrations of oxidative monoester phthalate metabolites in milk and surrogate fluids (serum, saliva, and urine) of 33 lactating North Carolina women. Methods We analyzed serum, saliva, urine, and milk for the oxidative phthalate metabolites mono(3-carboxypropyl) phthalate, mono(2-ethyl-5-carboxypentyl) phthalate (MECPP), mono(2-ethyl-5-hydroxyhexyl) phthalate, and mono(2-ethyl-5-oxohexyl) phthalate using isotope-dilution high-performance liquid chromatography tandem mass spectroscopy. Because only urine lacks esterases, we analyzed it for the hydrolytic phthalate monoesters. Results We detected phthalate metabolites in few milk (< 10%) and saliva samples. MECPP was detected in > 80% of serum samples, but other metabolites were less common (3–22%). Seven of the 10 urinary metabolites were detectable in ? 85% of samples. Monoethyl phthalate had the highest mean concentration in urine. Metabolite concentrations differed by body fluid (urine > serum > milk and saliva). Questionnaire data suggest that frequent nail polish use, immunoglobulin A, and fasting serum glucose and triglyceride levels were increased among women with higher concentrations of urinary and/or serum phthalate metabolites; motor vehicle age was inversely correlated with certain urinary phthalate concentrations. Conclusions Our data suggest that phthalate metabolites are most frequently detected in urine of lactating women and are less often detected in serum, milk, or saliva. Urinary phthalate concentrations reflect maternal exposure and do not represent the concentrations of oxidative metabolites in other body fluids, especially milk.

Hines, Erin P.; Calafat, Antonia M.; Silva, Manori J.; Mendola, Pauline; Fenton, Suzanne E.

2009-01-01

29

The evolutionary origin of the vasopressin/V2-type receptor/aquaporin axis and the urine-concentrating mechanism.  

PubMed

In this mini-review, current evidence for how the vasopressin/V2-type receptor/aquaporin axis developed co-evolutionary as a crucial part of the urine-concentrating mechanism will be presented. The present-day human kidney, allowing the concentration of urine up to a maximal osmolality around 1200 mosmol kg(-1)-or urine to plasma osmolality ratio around 4-with essentially no sodium secreted is the result of up to 3 billion years evolution. Moving from aquatic to terrestrial habitats required profound changes in kidney morphology, most notable the loops of Henle modifying the kidneys from basically a water excretory system to a water conserving system. Vasopressin-like molecules has during the evolution played a significant role in body fluid homeostasis, more specifically, the osmolality of body liquids by controlling the elimination/reabsorption of fluid trough stimulating V2-type receptors to mobilize aquaporin water channels in the renal collector tubules. Recent evidence supports that all components of the vasopressin/V2-type receptor/aquaporin axis can be traced back to early precursors in evolutionary history. The potential clinical and pharmacological implications of a better phylogenetic understanding of these biological systems so essential for body fluid homeostasis relates to any pathological aspects of the urine-concentrating mechanism, in particular deficiencies of any part of the vasopressin-V2R-AQP2 axis causing central or nephrogenic diabetes insipidus-and for broader patient populations also in preventing and treating disturbances in human circadian regulation of urine volume and osmolality that may lead to enuresis and nocturia. PMID:22374125

Juul, Kristian Vinter

2012-02-29

30

Effects of tap water lead, water hardness, alcohol, and cigarettes on blood lead concentrations  

Microsoft Academic Search

A survey of middle-aged men in 24 British towns has found pronounced geographical variation in blood lead concentrations. Towns with the highest mean blood lead concentrations have soft water supplies and have the highest water lead concentrations. Individual blood lead can be considerably increased by raised household tap water lead concentrations. Mean blood lead is estimated to be 43% higher

S J Pocock; A G Shaper; M Walker; C J Wale; B Clayton; T Delves; R F Lacey; R F Packham; P Powell

1983-01-01

31

Triazolothienopyrimidine Inhibitors of Urea Transporter UT-B Reduce Urine Concentration  

PubMed Central

Urea transport (UT) proteins facilitate the concentration of urine by the kidney, suggesting that inhibition of these proteins could have therapeutic use as a diuretic strategy. We screened 100,000 compounds for UT-B inhibition using an optical assay based on the hypotonic lysis of acetamide-loaded mouse erythrocytes. We identified a class of triazolothienopyrimidine UT-B inhibitors; the most potent compound, UTBinh-14, fully and reversibly inhibited urea transport with IC50 values of 10 nM and 25 nM for human and mouse UT-B, respectively. UTBinh-14 competed with urea binding at an intracellular site on the UT-B protein. UTBinh-14 exhibited low toxicity and high selectivity for UT-B over UT-A isoforms. After intraperitoneal administration of UTBinh-14 in mice to achieve predicted therapeutic concentrations in the kidney, urine osmolality after administration of 1-deamino-8-D-arginine-vasopressin was approximately 700 mosm/kg H2O lower in UTBinh-14–treated mice than vehicle-treated mice. UTBinh-14 also increased urine output and reduced urine osmolality in mice given free access to water. UTBinh-14 did not reduce urine osmolality in UT-B knockout mice. In summary, these data provide proof of concept for the potential utility of UT inhibitors to reduce urinary concentration in high-vasopressin, fluid-retaining conditions. The diuretic mechanism of UT inhibitors may complement the action of conventional diuretics, which target sodium transport.

Yao, Chenjuan; Anderson, Marc O.; Zhang, Jicheng; Yang, Baoxue; Phuan, Puay-Wah

2012-01-01

32

A magnetic bead-based method for concentrating DNA from human urine for downstream detection.  

PubMed

Due to the presence of PCR inhibitors, PCR cannot be used directly on most clinical samples, including human urine, without pre-treatment. A magnetic bead-based strategy is one potential method to collect biomarkers from urine samples and separate the biomarkers from PCR inhibitors. In this report, a 1 mL urine sample was mixed within the bulb of a transfer pipette containing lyophilized nucleic acid-silica adsorption buffer and silica-coated magnetic beads. After mixing, the sample was transferred from the pipette bulb to a small diameter tube, and captured biomarkers were concentrated using magnetic entrainment of beads through pre-arrayed wash solutions separated by small air gaps. Feasibility was tested using synthetic segments of the 140 bp tuberculosis IS6110 DNA sequence spiked into pooled human urine samples. DNA recovery was evaluated by qPCR. Despite the presence of spiked DNA, no DNA was detectable in unextracted urine samples, presumably due to the presence of PCR inhibitors. However, following extraction with the magnetic bead-based method, we found that ?50% of spiked TB DNA was recovered from human urine containing roughly 5×10(3) to 5×10(8) copies of IS6110 DNA. In addition, the DNA was concentrated approximately ten-fold into water. The final concentration of DNA in the eluate was 5×10(6), 14×10(6), and 8×10(6) copies/µL for 1, 3, and 5 mL urine samples, respectively. Lyophilized and freshly prepared reagents within the transfer pipette produced similar results, suggesting that long-term storage without refrigeration is possible. DNA recovery increased with the length of the spiked DNA segments from 10±0.9% for a 75 bp DNA sequence to 42±4% for a 100 bp segment and 58±9% for a 140 bp segment. The estimated LOD was 77 copies of DNA/µL of urine. The strategy presented here provides a simple means to achieve high nucleic acid recovery from easily obtained urine samples, which does not contain inhibitors of PCR. PMID:23861895

Bordelon, Hali; Russ, Patricia K; Wright, David W; Haselton, Frederick R

2013-07-08

33

Maple syrup urine disease: Branchedchain amino acid concentrations and metabolism in cultured human lymphoblasts  

Microsoft Academic Search

The intracellular concentration of free leucine, isoleucine, and valine and their metabolism were studied in lymphoblast cultures established from peripheral blood of an individual with maple syrup urine disease (MSUD) and a control subject. Branched-chain a-keto acid decarboxylase activity in the MSUD cells was 10% or less of the control value as measured by the ability of the cells to

Stephen D. Skaper; Daniel P. Molden; J. Edwin Seegmiller

1976-01-01

34

Concentration of urine in a central core model of the renal counterflow system  

Microsoft Academic Search

Concentration of urine in a central core model of the renal counterflow system. In this model descending Henle's limbs (DHL), ascending Henle's limbs (AHL) and collecting ducts (CD) exchange with a central vascular core (VC) formed by vasa recta loops—assumed so highly permeable that the core functions as a single tube, open at the cortical end and closed at the

John L Stephenson

1972-01-01

35

Nickel concentrations in serum and urine of patients with nickel eczema  

Microsoft Academic Search

This study is a part of the Biological Risk Assessment of Human Metal Sensitisation (BRAHMS) project with the aim of elucidating clinical and physiological effects of repeated exposures to low concentrations of metal allergens. Nickel allergic individuals (n=35) with hand eczema and healthy controls (n=30) were included in the study. Both groups had similar levels of nickel in urine, while

J. M Christensen; J Kristiansen; N. H Nielsen; T Menné; K Byrialsen

1999-01-01

36

CAFFEINE INTAKE AND URINE CAFFEINE CONCENTRATIONS AMONG THAI VOLUNTEERS LIVING IN  

Microsoft Academic Search

Caffeine is a psychoactive substance that is not legally regulated. Moreover, it is found in various forms of foodstuff. This study aimed to investigate caffeine intake and knowledge concerning caffeine health effects in a community of Thailand, Nakhonnayok province. A questionnaire was used to survey how people consumed caffeine-containing foodstuff daily. Urine caffeine concentrations analyzed by GC\\/NPD method were used

37

Seafood Intake and Urine Concentrations of Total Arsenic, Dimethylarsinate and Arsenobetaine in the US Population  

PubMed Central

Background Seafood is the main source of organic arsenic exposure (arsenobetaine, arsenosugars and arsenolipids) in the population. Arsenosugars and arsenolipids are metabolized to several species including dimethylarsinate (DMA). Objective Evaluate the association of seafood intake with spot urine arsenic concentrations in the 2003–2006 National Health Nutrition and Examination Survey (NHANES). Methods We studied 4276 participants ?6 y. Total arsenic was measured using inductively coupled plasma dynamic reaction cell mass spectrometry (ICPMS). Urine DMA and arsenobetaine were measured by high-performance liquid chromatography coupled with ICPMS. Results Participants reporting seafood in the past 24-h had higher urine concentrations of total arsenic (median 24.5 vs. 7.3 µg/L), DMA (6.0 vs. 3.5 µg/L), arsenobetaine (10.2 vs. 0.9 µg/L) and total arsenic minus arsenobetaine (11.0 vs. 5.5 µg/L). Participants reporting seafood ?2/wk vs. never during the past year had 2.3 (95% confidence interval 1.9, 2.7), 1.4 (1.2, 1.6), 6.0 (4.6, 7.8) and 1.7 (1.4, 2.0) times higher (p-trend <0.001) concentrations of total arsenic, DMA, arsenobetaine and total arsenic minus arsenobetaine, respectively. In participants without detectable arsenobetaine and in analyses adjusted for arsenobetaine, seafood consumption in the past year was not associated with total arsenic or DMA concentrations in urine. Conclusion Seafood intake was a major determinant of increased urine concentrations of total arsenic, DMA, arsenobetaine and total arsenic minus arsenobetaine in the US population. Epidemiologic studies that use total arsenic, DMA, the sum of inorganic arsenic, methylarsonate and DMA, and total arsenic minus arsenobetaine as markers of inorganic arsenic exposure and/or metabolism need to address seafood intake.

Navas-Acien, Ana; Francesconi, Kevin A.; Silbergeld, Ellen K; Guallar, Eliseo

2010-01-01

38

Pesticide Residues in Urine of Adults Living in the United States: Reference Range Concentrations  

Microsoft Academic Search

We measured 12 analytes in urine of 1000 adults living in the United States to establish reference range concentrations for pesticide residues. We frequently found six of these analytes: 2,5-dichlorophenol (in 98% of adults); 2,4-dichlorophenol (in 64%); 1-naphthol (in 86%); 2-naphthol (in 81%); 3,5,6-trichloro-2-pyridinol (in 82%); and pentachlorophenol (in 64%). The 95th percentile concentration (95thPC) for 2,5-dichlorophenol (indicative of p-dichlorobenzene

R. H. Hill; S. L. Head; S. Baker; M. Gregg; D. B. Shealy; S. L. Bailey; C. C. Williams; E. J. Sampson; L. L. Needham

1995-01-01

39

Lead Concentrations in Inner-City Soils as a Factor in the Child Lead Problem.  

ERIC Educational Resources Information Center

Excess lead concentration (resulting primarily from vehicular emissions) in Baltimore's inner city soils probably has a bearing on that city's child lead poisoning problem. Soil lead concentrations were lower outside the inner city. (GC)

Mielke, Howard W.; And Others

1983-01-01

40

Comparative physiology and architecture associated with the mammalian urine concentrating mechanism: role of inner medullary water and urea transport pathways in the rodent medulla.  

PubMed

Comparative studies of renal structure and function have potential to provide insights into the urine-concentrating mechanism of the mammalian kidney. This review focuses on the tubular transport pathways for water and urea that play key roles in fluid and solute movements between various compartments of the rodent renal inner medulla. Information on aquaporin water channel and urea transporter expression has increased our understanding of functional segmentation of medullary thin limbs of Henle's loops, collecting ducts, and vasa recta. A more complete understanding of membrane transporters and medullary architecture has identified new and potentially significant interactions between these structures and the interstitium. These interactions are now being introduced into our concept of how the inner medullary urine-concentrating mechanism works. A variety of regulatory pathways lead directly or indirectly to variable patterns of fluid and solute movements among the interstitial and tissue compartments. Animals with the ability to produce highly concentrated urine, such as desert species, are considered to exemplify tubular structure and function that optimize urine concentration. These species may provide unique insights into the urine-concentrating process.(1) PMID:23364530

Pannabecker, Thomas L

2013-01-30

41

Mercury, lead and cadmium levels in the urine of 170 Spanish adults: a pilot human biomonitoring study.  

PubMed

Human biomonitoring is a well-recognized tool for estimating the exposure of human populations to environmental pollutants. However, information regarding biomarker concentrations of many environmental chemicals in the general population is limited for many countries. The Spanish Environment Ministry has recently funded a human biomonitoring study on the Spanish general population. This study aims to determine reference levels for several biomarkers, especially heavy metals, persistent organic pollutants (POPs) and cotinine, in urine, whole blood, serum and hair, and will involve 2000 volunteers throughout Spain. Samples were taken during 2009-2010 and analyses are currently underway. The results presented herein were obtained in a pilot study carried out in the Madrid region. The study group comprised 170 volunteers, of which 79% were female and 21% male (age: 23-66 years). All participants were asked to complete a questionnaire regarding diet and living habits and provides a morning urine sample. The geometric means for total mercury (Hg), lead (Pb) and cadmium (Cd) were 1.23, 1.11 and 0.25 ?g/g creatinine, respectively. Levels of Pb and Hg were higher than those reported for the general population in the USA and Germany, whereas Cd was in the same range (CDC, 2009; Becker et al., 2003). The values reported here are similar to those reported in other Spanish studies. PMID:21968334

Castaño, Argelia; Sánchez-Rodríguez, Jinny E; Cañas, Ana; Esteban, Marta; Navarro, Carmen; Rodríguez-García, Ana C; Arribas, Misericordia; Díaz, Gema; Jiménez-Guerrero, José A

2011-10-02

42

A novel ETA-AAS background reduction method for determination of lead and cadmium in urine.  

PubMed

Urinary lead and cadmium level were determined in double diluted urine samples using two modifiers: 1% HNO3 (own modification) and 1.6% NH4H2PO4 that is generally used for matrix modification. The background signal is reduced in the samples diluted with 1% HNO3 because of the modifying effect of nitric acid. Lower variation coefficients were obtained in a run of 10 determinations of each of the samples processed by our method which is an advantageous feature compared with the method using 1.6% NH4H2PO4 as a modifier. Recovery is between 95 and 105% for both methods. The analytical performance, flexible pre-instrumental preparation and minimized risk of sample contamination make the use of 1% HNO3 modifier a reliable method in the routine practice of determination of the urinary Pb and Cd level. PMID:9630762

Tarulov, Z; Kotzev, T; Tsvetkova, T

1998-01-01

43

A comparison of concentrations of lead in human tissues.  

PubMed Central

This postmortem study of lead concentrations in the tissues of 129 subjects is an extension to a report by Barry and Mossman (1970). Lead concentrations in bone greatly exceeded the concentrations in soft tissues and were highest in the dense bones. Bone lead concentrations increased with age in both sexes, more especially in male subjects and in dense bone, varying between mean values of 2-16 ppm in the ribs of children to over 50 ppm in the dense petrous temporal bones of elderly male adults. Male adults contained over 30% more lead in their bones than females. Mean concentrations of lead in the soft tissues varied from less than 0-1 ppm in organs such as muscle and heart to over 2 ppm in the aorta. In most tissues with lead values in excess of 0-2 ppm the male concentrations exceeded female values by about 30%. With the exception of the aorta, spleen, lung, and prostate, lead concentrations did not increase with age in the soft tissues of either sex after about the second decade of life. Children showed concentrations of lead in their soft tissues comparable to female adults, but the concentrations in bone were much lower. It is suggested that children do not possess the same capacity as adults to retain lead in bone. In male adults occupationally exposed to lead the concentrations of lead in bone exceeded the concentrations in unexposed male adults within the same age group by two-to three-fold. Soft tissue lead concentrations between the two groups were less divergent. An assessment of the total body burden of lead revealed higher levels in adult male subjects than in females at mean values of 164-8 mg compared to 103-6 mg, respectively. Over 90% of the total body burden of lead in adults was in bone, of which over 70% was in dense bone. Male adults occupationally exposed to lead had mean total body burdens of 566-4 mg Pb, of which 97% was in bone. The release of lead from bone in conjunction with calcium was not considered to be of physiological significance. Lead concentrations of hair and nails were higher than soft tissue lead concentrations and varied widely. Hair lead measurements were not considered to provide a reliable assessment of lead absorption. The concentrations of lead in tissues of a mixed group of subjects with no known occupational exposure to lead have been shown to be comparable to the findings in earlier studies. Present levels of lead in the environment are not considered to be a hazard to the health of the population in general.

Barry, P S

1975-01-01

44

Trihalomethane Concentrations in Swimmers' and Bath Attendants' Blood and Urine after Swimming or Working in Indoor Swimming Pools  

Microsoft Academic Search

The influence of working or swimming in indoor swimming pools on the concentrations of four trihalomethanes (haloforms) in blood and urine was investigated. Different groups (bath attendants, agonistic swimmers, normal swimmers, sampling person) were compared. The proportions of trihalomethanes in blood and urine correlated roughly with those in water and ambient air. Higher levels of physical activity were correlated with

Karl Cammann; Karl Hübner

1995-01-01

45

Electrothermal atomization atomic absorption spectrometry for the determination of lead in urine: results of an interlaboratory study  

NASA Astrophysics Data System (ADS)

Results of an interlaboratory study are reported for the determination of lead in urine. Two levels of a lyophilized material containing biologically-bound lead were prepared using pooled urine obtained from lead-poisoned children undergoing the CaNa 2EDTA mobilization test. The materials were circulated to a group of reference laboratories that participate in the `New York State Proficiency Testing Program for Blood Lead'. Results of the initial round-robin gave all-method consensus target values of 145±22 ?g/l (S.D.) for lot 17 and 449±43 ?g/l (S.D.) for lot 20. The interlaboratory exercise was repeated some 5 years later and consensus target values were re-calculated using the grand mean (excluding outliers) of results reported by laboratories using electrothermal atomization atomic absorption spectrometry (ETAAS). The re-calculated target values were 139±10 ?g/l (S.D.) and 433±12 ?g/l (S.D.). The urine reference materials were also analyzed for lead by several laboratories using other instrumental techniques including isotope dilution (ID), inductively coupled plasma (ICP) mass spectrometry (MS), flame atomic absorption with extraction, ICP-atomic emission spectrometry, ID-gas chromatography MS and flow injection-hydride generation AAS, thus providing a rich source of analytical data with which to characterize them. The materials were also used in a long-term validation study of an ETAAS method developed originally for blood lead determinations that has since been used unmodified for the determination of lead in urine also. Recently, urine lead method performance has been tracked in a proficiency testing program specifically for this analysis. In addition, a number of commercial control materials have been analyzed and evaluated.

Parsons, Patrick J.; Slavin, Walter

1999-05-01

46

Multielement determination of cadmium and lead in urine by simultaneous electrothermal atomic absorption spectrometry with an end-capped graphite tube.  

PubMed

A method for the multielement determination of cadmium and lead in urine is proposed by simultaneous electrothermal atomic absorption spectrometry (SIMAAS) with an end-capped transversely heated graphite atomizer (EC-THGA). The best conditions for cadmium and lead determination were obtained in the presence of NH4H2PO4 as a chemical modifier, using 500 degrees C and 1800 degrees C as the pyrolysis and atomization temperatures, respectively. Urine samples were diluted 1 + 4 directly in autosampler cups with a mixture of 0.125% (w/v) Triton X-100 + 2.5% (v/v) HNO3 + 0.31% (w/v) NH4H2PO4. The optimized heating program was carried out in 57 s, and the instrument calibration was done with aqueous reference solutions. The use of EC-THGA increased the sensitivity of cadmium and lead by 14% and 25%, respectively. The detection limits (n = 20, 3delta) were 0.03 microg L(-1) (0.36 pg) for cadmium and 0.57 microg L(-1) (6.8 pg) for lead. The performance of EC-THGA was acceptable up to 500 heating cycles. The reliability of the entire procedure was checked with the analysis of a lyophilized urine certified reference material. The found concentrations were in agreement with the recommended values (95% confidence level). PMID:14640451

Correia, Paulo R M; Nomura, Cassiana S; Oliveira, Pedro V

2003-11-01

47

Fluoride in workplace air and in urine of workers concentrating fluorspar  

SciTech Connect

The urinary fluoride concentrations of workers exposed to calcium fluoride (CaF2) during fluorspar processing were measured. Personal dust measurement showed that the mean occupational exposure to fluoride for 12 workers in the most dusty environment was 24.3 mg/m3, which is 9.7 times the threshold limit value (TLV) of 2.5 mg/m3. Exposure was below the TLV for the remaining 23 workers. Urinary fluoride concentrations were measured pre- and postshift. The heavily exposed workers had a mean preshift concentration of 3.3 mg/liter (range 1.4-8.5 mg/liter), only slightly higher than the mean of 2.8 mg/liter (range 1.3-4.2 mg/liter) in the workers with fluoride exposure below the TLV. Four of the preshift concentrations exceeded the recommended upper limit of 4 mg/liter. The mean postshift concentration for workers exposed above the TLV was 4.4 mg/liter (range 2.4-7.1 mg/liter) and the difference between pre- and postshift concentrations was significant (p less than 0.05). Only one urinary concentration exceeded the recommended upper limit of 7 mg/liter. There was poor correlation between intensity of environmental exposure to fluorspar and postshift fluoride concentration in the urine. Eighteen workers provided a urine sample 7-14 hr after the end of a shift. The mean fluoride concentration was 4.7 mg/liter (range 2.4-11.7 mg/liter), which exceeded their postshift concentration by 0.2 mg/liter. These results indicate that the low aqueous solubility of fluorspar reduced the biologic availability of the fluoride ion but that this did not prevent excessive fluoride absorption in some workers.

Rees, D.; Rama, D.B.; Yousefi, V. (National Centre for Occupational Health, Johannesburg (South Africa))

1990-01-01

48

BLOOD LEAD CONCENTRATION AND DELAYED PUBERTY IN GIRLS  

EPA Science Inventory

Background Environmental lead exposure has been linked to alterations in growth and endocrine function. It is not known whether such exposure affects pubertal development. Methods We analyzed the relations between blood lead concentration and pubertal...

49

An evaluation of lead concentrations in imported hot sauces.  

PubMed

In the last decade, the U.S. Food and Drug Administration (FDA) has issued several warnings and recalls for food products that exceed FDA standards for lead. Products containing chili peppers and salt were often suspected as sources of lead contamination, and included items such as candy that are routinely investigated. However, products such as hot sauces that contain similar ingredients have not been the focus of evaluations. This study quantified lead concentrations in imported hot sauces, evaluated product compliance to existing United States standards, and calculated potential dietary lead exposure for children using the Integrated Exposure Uptake Biokinetic Model. Finally, recommendations for reducing the risk of lead exposure from hot sauces are provided. Twenty-five (25) bottles of imported hot sauces manufactured in Mexico and South America were purchased in Clark County, Nevada. All hot sauces were analyzed for lead concentrations, pH, and leaded packaging. Hot sauces were analyzed by inductively coupled plasma mass spectrometry and packaging was analyzed using x-ray fluorescence technology. Four brands of hot sauces (16%) exceeded 0.1 ppm lead, the current FDA action level for lead in candy. Hot sauces with lead concentrations >0.1 ppm lead contained salt and were manufactured in Mexico. Subsequent analysis of additional lots of hot sauces exceeding 0.1 ppm lead revealed inconsistent lead concentrations between and within manufacturer lots. The lead concentrations of the plastic hot sauce lids ranged from below the limit of detection to 2,028 ppm lead. There was no association between lead concentrations in hot sauces and pepper type. These results indicate the need for more rigorous screening protocols for products imported from Mexico, the establishment of an applicable standard for hot sauce, and resources to allow for the enforcement of existing food safety policies. The data reported herein represent the first known investigation of lead concentrations in hot sauces. PMID:23581685

Berger Ritchie, Jennifer A; Gerstenberger, Shawn L

2013-01-01

50

Dietary and sociodemographic determinants of bisphenol A urine concentrations in pregnant women and children.  

PubMed

Bisphenol A (BPA) exposure during early life may have endocrine-disrupting effects, but the dietary and sociodemographic predictors of BPA exposure during pregnancy and childhood remain unclear. Our aim was to evaluate the correlations between, and sociodemographic and dietary predictors of, serial urinary BPA concentrations measured during pregnancy and childhood in a Spanish birth cohort study. BPA was measured in two spot urine samples collected from 479 women during the first and third trimester of pregnancy and in one urine sample from their 4-year old children (n=130). Average dietary intakes were reported in food frequency questionnaires during the first and third pregnancy trimester and at age 4years. Multivariate mixed models and linear regression models were used to estimate associations between sociodemographic and dietary factors and BPA concentrations. A small, but statistically significant correlation was found between serial maternal BPA concentrations measured during pregnancy (r=0.17). Pregnant women who were younger, less-educated, smoked, and who were exposed to second-hand tobacco smoke (SHS) had higher BPA concentrations than others. BPA concentrations were also higher in children exposed to SHS. High consumption of canned fish during pregnancy was associated with 21% [GM ratio=1.21; 95%CI 1.02, 1.44] and 25% [GM ratio=1.25; 95%CI 1.05, 1.49] higher urinary BPA concentrations in the first and third pregnancy trimester, respectively, compared to the lowest consumption group. This study suggests that canned fish may be a major source of BPA during pregnancy in Spain, a country of high canned fish consumption. Further evaluation of specific BPA exposure sources in the sociodemographic group of younger women who smoke, are exposed to SHS, and have a low educational level is needed. Studies identifying sources of exposure would benefit from repeat BPA measurements and questionnaires specifically focused on dietary and packaging sources. PMID:23542682

Casas, Maribel; Valvi, Damaskini; Luque, Noelia; Ballesteros-Gomez, Ana; Carsin, Anne-Elie; Fernandez, Marieta F; Koch, Holger M; Mendez, Michelle A; Sunyer, Jordi; Rubio, Soledad; Vrijheid, Martine

2013-03-26

51

Essential and toxic element concentrations in blood and urine and their associations with diet: results from a Norwegian population study including high-consumers of seafood and game.  

PubMed

The first aim of the study was to evaluate calculated dietary intake and concentrations measured in blood or urine of essential and toxic elements in relation to nutritional and toxicological reference values. The second aim was to identify patterns of the element concentrations in blood and urine and to identify possible dietary determinants of the concentrations of these elements. Adults with a known high consumption of environmental contaminants (n=111), and a random sample of controls (n=76) answered a validated food frequency questionnaire (FFQ). Complete data on biological measures were available for 179 individuals. Blood and urine samples were analyzed for selenium, iodine, arsenic, mercury, cadmium and lead. Principal component analysis was used to identify underlying patterns of correlated blood and urine concentrations. The calculated intakes of selenium, iodine, inorganic arsenic and mercury were within guideline levels. For cadmium 24% of the high consumer group and 8% of the control group had intakes above the tolerable weekly intake. Concentrations of lead in blood exceeded the bench-mark dose lower confidence limits for some participants. However, overall, the examined exposures did not give rise to nutritional or toxicological concerns. Game consumption was associated with lead in blood (B(ln) 0.021; 95%CI:0.010, 0.031) and wine consumption. Seafood consumption was associated with urinary cadmium in non-smokers (B(ln) 0.009; 95%CI:0.003, 0.015). A novel finding was a distinct pattern of positively associated biological markers, comprising iodine, selenium, arsenic and mercury (eigenvalue 3.8), reflecting seafood intake (B 0.007; 95%CI:0.004, 0.010). The study clearly demonstrates the significance of seafood as a source of both essential nutrients and toxic elements simultaneously and shows that exposure to various essential and toxic elements can be intertwined. PMID:23867847

Birgisdottir, B E; Knutsen, H K; Haugen, M; Gjelstad, I M; Jenssen, M T S; Ellingsen, D G; Thomassen, Y; Alexander, J; Meltzer, H M; Brantsæter, A L

2013-07-15

52

Acute changes in arginine vasopressin, sweat, urine and serum sodium concentrations in exercising humans: does a coordinated homeostatic relationship exist?  

PubMed Central

The parallel response of sweat rate and urine production to changes in plasma osmolality and volume support a role for arginine vasopressin (AVP) as the main endocrine regulator of both excretions. A maximal test to exhaustion and a steady-state run on a motorised treadmill were both completed by 10 moderately trained runners, 1 week apart. Sweat, urine and serum sodium concentrations ([Na+]) were evaluated in association with the plasma concentrations of cytokines, neurohypophyseal and natriuretic peptides, and adrenal steroid hormones. When data from both the high-intensity and steady-state runs were combined, significant linear correlations were noted between: sweat [Na+] versus postexercise urine [Na+] (r = 0.80; p<0.001), postexercise serum [Na+] versus both postexercise urine [Na+] (r = 0.56; p<0.05) and sweat [Na+] (r = 0.64; p<0.01) and postexercise urine [Na+] versus postexercise plasma arginine vasopressin concentration ([AVP]P) (r = 0.48; p<0.05). A significant positive correlation was noted between postexercise [AVP]P and sweat [Na+] during the steady-state condition only (r = 0.66; p<0.05). These correlations suggest that changes in serum [Na+] during exercise may evoke corresponding changes in sweat and urine [Na+], which are likely regulated coordinately by changes in [AVP]P to preserve body fluid homeostasis.

Hew-Butler, T; Noakes, T D; Soldin, S J; Verbalis, J G

2013-01-01

53

Blood pressure and blood lead concentration in bus drivers  

SciTech Connect

San Francisco bus drivers have an increased prevalence of hypertension. This study examined relationships between blood lead concentration and blood pressure in 342 drivers. The analysis reported in this study was limited to subjects not on treatment for hypertension (n = 288). Systolic and diastolic pressure varied from 102 to 173 mm Hg and from 61 to 105 mm Hg, respectively. The blood lead concentration varied from 2 to 15 ..mu..g/dL. The relationship between blood pressure and the logarithm of blood lead concentration was examined using multiple regression analysis. Covariates included age, body mass index, sex, race, and caffeine intake. The largest regression coefficient relating systolic blood pressure and blood lead concentration was 1.8 mm Hg/ln (..mu..g/dL). The coefficient for diastolic blood pressure was 2.5 mm Hg/ln (..mu..g/dL). These findings suggest effects of lead exposure at lower blood lead concentrations than those concentrations that have previously been linked with increases in blood pressure.

Sharp, D.S.; Osterloh, J.; Becker, C.E.; Bernard, B.; Smith, A.H.; Fisher, J.M.; Syme, S.L.; Holman, B.L.; Johnston, T.

1988-06-01

54

The Use of Hydrogel Microparticles to Sequester and Concentrate Bacterial Antigens in a Urine Test for Lyme Disease  

PubMed Central

Hydrogel biomarker capturing microparticles were evaluated as a biomaterial to amplify the sensitivity of urine testing for infectious disease proteins. Lyme disease is a bacterial infection transmitted by ticks. Early diagnosis and prompt treatment of Lyme disease reduces complications including arthritis and cardiac involvement. While a urine test is highly desirable for Lyme disease screening, this has been difficult to accomplish because the antigen is present at extremely low concentrations, below the detection limit of clinical immunoassays. N-isopropylacrylamide (NIPAm) – acrylic acid (AAc) microparticles were covalently functionalized with amine containing dyes via amidation of carboxylic groups present in the microparticles. The dyes act as affinity baits towards protein analytes in solution. NIPAm/AAc microparticles functionalized with acid black 48 (AB48) mixed with human urine, achieved close to one hundred percent capture and 100 percent extraction yield of the target antigen. In urine, microparticles sequestered and concentrated Lyme disease antigens 100 fold, compared to the absence of microparticles, achieving an immunoassay detection sensitivity of 700 pg/mL in 10mL urine. Antigen present in a single infected tick could be readily detected following microparticle sequestration. Hydrogel microparticles functionalized with high affinity baits can dramatically increase the sensitivity of urinary antigen tests for infectious diseases such as Lyme disease. These findings justify controlled clinical studies evaluating the sensitivity and precision of Lyme antigen testing in urine.

Douglas, Temple; Tamburro, Davide; Fredolini, Claudia; Espina, Benjamin; Lepene, Benjamin S.; Ilag, Leopold; Espina, Virginia; Petricoin, Emanuel F.; Liotta, Lance A.; Luchini, Alessandra

2010-01-01

55

A brief history of theories concerning the mammalian urine concentrating mechanism.  

PubMed

The mechanism by which the mammalian kidney creates the osmotic gradient necessary for urine concentration remains an open question. We present a brief survey of the give-and-take between theory and experiment on this question over the last half century. We start with the introduction of the countercurrent multiplier paradigm in 1951. We finish with a description of a recent suggestion that the explanation for the enigmatic inner medullary osmotic gradient may reside in the very metabolism of the inner medullary cells, which are required by the region's hypoxia to obtain their ATP largely from anaerobic glycolysis and which thus, by the same token, furnish net osmoles to the medullary interstitium by converting glucose to lactate. PMID:11804242

Thomas, S R

2001-01-01

56

Nickel concentrations in serum and urine of patients with nickel eczema.  

PubMed

This study is a part of the Biological Risk Assessment of Human Metal Sensitisation (BRAHMS) project with the aim of elucidating clinical and physiological effects of repeated exposures to low concentrations of metal allergens. Nickel allergic individuals (n = 35) with hand eczema and healthy controls (n = 30) were included in the study. Both groups had similar levels of nickel in urine, while the level of nickel in serum was significantly lower in nickel allergic individuals compared to controls. Nickel allergic individuals had a significantly lower intake of nickel-rich food items (chocolate, nuts, beans, porridge oats). Serum nickel levels correlated with intake of these foods, suggesting that the difference in serum nickel levels was caused by differences in dietary nickel intake. PMID:10511261

Christensen, J M; Kristiansen, J; Nielsen, N H; Menné, T; Byrialsen, K

1999-09-01

57

Lead concentrations and labeling of new paint in cameroon.  

PubMed

In spite of the availability of substitutes for lead compounds used in paints, manufacturers continue to produce these paints for decorative and industrial applications. We report here on the concentration of lead in new paint sold in Cameroon and provide a summary of labeling practices on paints available in the country, based on a market survey. Investigators visited 76 retail and wholesale paint suppliers in Cameroon to collect information from paint product labels and to collect samples of paints to analyze for lead content. Only 8.5% of paints had labels identifying any of the ingredients, and none of the lead paints included any warning language. Based on a convenience sample (weighted to include multiple colors from the most common brands), 61 mostly enamel paints were purchased from retail outlets and analyzed for lead content (median: 2150 ppm; range: <21-500,000 ppm). Sixty-six percent of the new paint samples had concentrations exceeding the U.S. standard of 90 ppm total lead. All but one of the samples with lead concentrations greater than 90 ppm were also greater than 600 ppm. The largest manufacturer in the country-Seigneurie, a subsidiary of the U.S.-based company PPG-had significant lead concentrations in 9 out of 22 (41%) paints tested. There is an immediate need to adopt mandatory standards to limit the lead content of paint manufactured, imported, and sold in the country. To promote safer paint products we recommend the development of a third-party certification program for paints without added lead. These recommendations are consistent with the objectives of the Global Alliance to Eliminate Lead Paint established under the auspices of the United Nations to address this problem on a global scale. PMID:23472856

Gottesfeld, P; Kuepouo, G; Tetsopgang, S; Durand, K

2013-01-01

58

Mice with targeted disruption of the acyl-CoA binding protein display attenuated urine concentrating ability and diminished renal aquaporin-3 abundance.  

PubMed

The acyl-CoA binding protein (ACBP) is a small intracellular protein that specifically binds and transports medium to long-chain acyl-CoA esters. Previous studies have shown that ACBP is ubiquitously expressed but found at particularly high levels in lipogenic cell types as well as in many epithelial cells. Here we show that ACBP is widely expressed in human and mouse kidney epithelium, with the highest expression in the proximal convoluted tubules. To elucidate the role of ACBP in the renal epithelium, mice with targeted disruption of the ACBP gene (ACBP(-/-)) were used to study water and NaCl balance as well as urine concentrating ability in metabolic cages. Food intake and urinary excretion of Na(+) and K(+) did not differ between ACBP(-/-) and (+/+) mice. Interestingly, however, water intake and diuresis were significantly higher at baseline in ACBP(-/-) mice compared with that of (+/+) mice. Subsequent to 20-h water deprivation, ACBP(-/-) mice exhibited increased diuresis, reduced urine osmolality, elevated hematocrit, and higher relative weight loss compared with (+/+) mice. There were no significant differences in plasma concentrations of renin, corticosterone, and aldosterone between mice of the two genotypes. After water deprivation, renal medullary interstitial fluid osmolality and concentrations of Na(+), K(+), and urea did not differ between genotypes and cAMP excretion was similar. Renal aquaporin-1 (AQP1), -2, and -4 protein abundances did not differ between water-deprived (+/+) and ACBP(-/-) mice; however, ACBP(-/-) mice displayed increased apical targeting of pS256-AQP2. AQP3 abundance was lower in ACBP(-/-) mice than in (+/+) control animals. Thus we conclude that ACBP is necessary for intact urine concentrating ability. Our data suggest that the deficiency in urine concentrating ability in the ACBP(-/-) may be caused by reduced AQP3, leading to impaired efflux over the basolateral membrane of the collecting duct. PMID:22237802

Langaa, Stine; Bloksgaard, Maria; Bek, Signe; Neess, Ditte; Nørregaard, Rikke; Hansen, Pernille B L; Marcher, Ann Britt; Frøkiær, Jørgen; Mandrup, Susanne; Jensen, Boye L

2012-01-11

59

Biomonitoring of urine mutagenicity with the Ames test: improvement of the extraction\\/concentration method  

Microsoft Academic Search

Comparative extraction efficiency of the pre-packed Bakerbond®-spe-SDB-1 resin and of Amberlite®-AD2 (XAD-2) resin, for the preparation of urine extracts in biomonitoring studies. Urine extracts were prepared in parallel with the Bakerbond® column and with the classical XAD-2 resin from urines (1) spiked with mutagenic chemicals, (2) collected from patients after chemotherapy, and (3) from smokers. Mutagenic activities were evaluated on

Véronique Andre; Pierre Lebailly; Edwige Deslandes; Michel Henry-Amar; Pascal Gauduchon

2002-01-01

60

Pyrophosphate does not influence calcium oxalate or calcium phosphate crystal formation in concentrated whole human urine  

Microsoft Academic Search

1) Low pyrophosphate urine was generated by passage through a nylon coil bearing immobilised inorganic pyrophosphatase. High pyrophosphate urine was made by addition of inorganic pyrophosphate. 2) Urine samples of low, normal, and high pyrophosphate content were rapidly evaporated at 37°C to 1,050 or 1,250 mosmol\\/L and the crystals formed studied by microscope, isotope and chemical methods. 3) Urinary pyrophosphate

P. C. Hallson; G. A. Rose; S. Sulaiman

1983-01-01

61

Architecture of vasa recta in the renal inner medulla of the desert rodent Dipodomys merriami: potential impact on the urine concentrating mechanism  

PubMed Central

We hypothesize that the inner medulla of the kangaroo rat Dipodomys merriami, a desert rodent that concentrates its urine to over 6,000 mosmol/kg H2O, provides unique examples of architectural features necessary for production of highly concentrated urine. To investigate this architecture, inner medullary vascular segments in the outer inner medulla were assessed with immunofluorescence and digital reconstructions from tissue sections. Descending vasa recta (DVR) expressing the urea transporter UT-B and the water channel aquaporin 1 lie at the periphery of groups of collecting ducts (CDs) that coalesce in their descent through the inner medulla. Ascending vasa recta (AVR) lie inside and outside groups of CDs. DVR peel away from vascular bundles at a uniform rate as they descend the inner medulla, and feed into networks of AVR that are associated with organized clusters of CDs. These AVR form interstitial nodal spaces, with each space composed of a single CD, two AVR, and one or more ascending thin limbs or prebend segments, an architecture that may lead to solute compartmentation and fluid fluxes essential to the urine concentrating mechanism. Although we have identified several apparent differences, the tubulovascular architecture of the kangaroo rat inner medulla is remarkably similar to that of the Munich Wistar rat at the level of our analyses. More detailed studies are required for identifying interspecies functional differences.

Issaian, Tadeh; Urity, Vinoo B.; Dantzler, William H.

2012-01-01

62

Fluoride increases lead concentrations in whole blood and in calcified tissues from lead-exposed rats.  

PubMed

Higher blood lead (BPb) levels have been reported in children living in communities that receive fluoride-treated water. Here, we examined whether fluoride co-administered with lead increases BPb and lead concentrations in calcified tissues in Wistar rats exposed to this metal from the beginning of gestation. We exposed female rats and their offspring to control water (Control Group), 100mg/L of fluoride (F Group), 30mg/L of lead (Pb Group), or 100mg/L of fluoride and 30mg/L of lead (F+Pb Group) from 1 week prior to mating until offspring was 81 days old. Blood and calcified tissues (enamel, dentine, and bone) were harvested at day 81 for lead and fluoride analyses. Higher BPb concentrations were found in the F+Pb Group compared with the Pb Group (76.7+/-11.0microg/dL vs. 22.6+/-8.5microg/dL, respectively; p<0.001). Two- to threefold higher lead concentrations were found in the calcified tissues in the F+Pb Group compared with the Pb Group (all p<0.001). Fluoride concentrations were similar in the F and in the F+Pb Groups. These findings show that fluoride consistently increases BPb and calcified tissues Pb concentrations in animals exposed to low levels of lead and suggest that a biological effect not yet recognized may underlie the epidemiological association between increased BPb lead levels in children living in water-fluoridated communities. PMID:20188782

Sawan, Rosangela M M; Leite, Giselle A S; Saraiva, Maria C P; Barbosa, Fernando; Tanus-Santos, Jose E; Gerlach, Raquel F

2010-02-25

63

Plasma and urine dimercaptopropanesulfonate concentrations after dermal application of transdermal DMPS (TD-DMPS).  

PubMed

2,3-Dimercaptopropane-1-sulfonate (DMPS) is a metal chelator approved in Europe for oral or intravenous use for heavy metal poisoning. Transdermally applied DMPS (TD-DMPS) is used by some alternative practitioners to treat autism, despite the absence of evidence for its efficacy. We found no literature evaluating the pharmacokinetics of the transdermal route of delivery or the ability of TD-DMPS to enhance urinary mercury elimination. We hypothesized that TD-DMPS is not absorbed. Eight adult volunteers underwent application of 1.5-3 drops/kg of TD-DMPS. Subjects provided 12-h urine collections the day before and day of application. Subjects underwent blood draws at 0, 30, 60,90, 120, and 240 min after TD-DMPS application. Plasma and urine were assayed for the presence of DMPS. Urine was assayed for any change in urinary mercury excretion after DMPS. One control subject ingested 250 mg of oral DMPS and underwent the same urine and blood collections and analyses. No subject had detectable urine DMPS or increased urine mercury excretion after TD-DMPS. One subject had detectable levels of DMPS in the 30-min plasma sample, suspected to be contamination. All other samples for that subject and the other seven subjects showed no detectable plasma DMPS. The control subject had detectable urine and plasma DMPS levels and increased urine mercury excretion. These results indicate that TD-DMPS is not absorbed. There was no increase in urine mercury excretion after TD-DMPS. Our results argue that TD-DMPS is an ineffective metal chelator. PMID:23143832

Cohen, Jennifer P; Ruha, Anne-Michelle; Curry, Steven C; Biswas, Kallol; Westenberger, Benjamin; Ye, Wei; Caldwell, Kathleen L; Lovecchio, Frank; Burkhart, Keith; Samia, Nasr

2013-03-01

64

Evaluation of Dietary Nitrogen Utilization in Dairy Cows Based on Urea Concentrations in Blood, Urine and Milk, and on Urinary Concentration of Purine Derivatives  

Microsoft Academic Search

The effects of level and degradability of dietary protein on urea in blood, urine and milk, and on the urinary purine derivatives and creatinine in dairy cows, were studied. Diurnal variation in urinary concentration of urea, allantoin and creatinine was also studied. A total of 24 multiparous lactating dairy cows were selected from a production experiment and divided into two

Horacio Leandro Gonda; Jan Erik Lindberg

1994-01-01

65

[Progesterone and pregnanediol-glucuronid concentrations in saliva, milk and urine of female alpacas and their application in pregnancy diagnosis].  

PubMed

The objective of the present study was the measurement of the pregnancy associated hormones progesterone (P4) and pregnanediol-glucuronide (PdG) in saliva, milk and urine of alpacas and their potential use in pregnancy diagnosis. Sample of blood, saliva, milk and urine were obtained from 36 female alpacas before mating and throughout the pregnancy. Concentrations of P4 and PdG were determined using an enzyme immunoassay (EIA). Pregnancy was checked by ultrasonography at any sampling time. The milk samples were also tested using a commercial on-farm progesterone kit which was designed for dairy cattle. EIA-Concentrations of P4 in blood, milk and urine and urine PdG concentrations were significantly higher in pregnant than in not pregnant alpacas. There was no difference in concentrations of P4 or PdG in saliva. The accuracy of the progesterone kit was 90% for diagnosis of pregnancy and 69% for non-pregnancy. However, 70% of the false positive results also showed relatively high P4 milk concentrations in the EIA. Values of P4 in blood and PdG in urine are comparable to previous reports in alpacas and therefore can be confirmed as an indicator for pregnancy. Saliva seems unsuitable in pregnancy diagnosis in alpacas, whereas milk seems to be an adequate alternative. The use of milk and urine would simplify the pregnancy diagnosis in alpacas since in contrast to the current methods (e. g. blood progesterone) the owners can take the samples. The avoidance of blood sampling results in a considerable stress reduction for the animals. P4 measurement in milk and PdG measurement in urine are good alternatives in pregnancy diagnosis during the first month of pregnancy, when a trans-abdominal ultrasonographic examination is not yet reliable. However, since high values of P4 and PdG only show the presence of active luteal tissue and therefore are indirect markers of pregnancy the diagnosis should be confirmed using ultrasound later in pregnancy. PMID:21141281

Volkery, Janine; Wittek, Thomas; Sobiraj, Axel; Gottschalk, Jutta; Einspanier, Almuth

66

Highly sensitive and rapid method for determination of fluoride ion concentrations in serum and urine using flow injection analysis with a fluoride ion-selective electrode  

Microsoft Academic Search

An apparatus for flow injection analysis (FIA) was developed to measure very low fluoride ion concentrations (<1 ?mol\\/l). The analytical conditions of the apparatus were investigated, and the instrument was used to determine fluoride ion concentrations in serum and urine. All interferences caused by serum and urine matrices were eliminated using the proposed method. The recovery was almost 100.0% for

Kazuyoshi Itai; Humio Tsunoda

2001-01-01

67

The concentration of bisphenol A in urine is affected by specimen collection, a preservative, and handling.  

PubMed

In urine specimens that were collected from pregnant women in a large cohort, 24% contained more than 10ng/ml of total bisphenol A (BPA), suggesting external contamination. Therefore, we conducted an investigation of the source(s) of extraneous BPA in the specimens. We found that under the conditions used to collect urine specimens in the epidemiologic study, contamination with BPA occurred, and by two separate mechanisms. PMID:23899777

Longnecker, M P; Harbak, K; Kissling, G E; Hoppin, J A; Eggesbo, M; Jusko, T A; Eide, J; Koch, H M

2013-07-27

68

Lead pellet ingestion and liver-lead concentrations in upland game birds from southern Ontario, Canada.  

PubMed

One-hundred twenty-three gizzards from upland game birds (chukar, Alectoris chukar; and common pheasant, Phasianus colchicus) harvested by hunters in southern Ontario, Canada, were examined for lead pellet ingestion by manual examination of gizzard contents and by radiography. Lead pellets were found to be ingested by chukars (6/76; 8%) and the common pheasant (16/47; 34%). Further, 13% (17/129) of the bird (wild turkey, Meleagris gallopavo; Hungarian partridge, Perdix perdix; chukar; and common pheasant) livers analyzed had elevated lead concentrations (> or =6 microg/g wet weight [ww]). Liver-lead concentrations above Health Canada's guideline for human consumption of fish protein (<0.5 microg/g ww) were found in 40% (51/129) of livers analyzed. Data indicate that the ingestion of lead pellets in upland game birds and the potential consumption of lead-contaminated meat by humans are concerns related to the continued use of lead shotshell for hunting. PMID:17763885

Kreager, N; Wainman, B C; Jayasinghe, R K; Tsuji, L J S

2007-08-31

69

Blood Lead Concentration and Delayed Puberty in Girls  

Microsoft Academic Search

methods We analyzed the relations between blood lead concentration and pubertal development among girls (defined as females 8 to 18 years of age) who were enrolled in a cross- sectional study (the third National Health and Nutrition Examination Survey) in which race was self-reported or proxy-reported: 600 were non-Hispanic white, 805 were non- Hispanic African-American, and 781 were Mexican-American girls.

Sherry G. Selevan; Deborah C. Rice; Karen A. Hogan; Susan Y. Euling; Andrea Pfahles-Hutchens; James Bethel

2010-01-01

70

Measurement of sodium ion concentration in undiluted urine with cation-selective polymeric membrane electrodes after the removal of interfering compounds  

PubMed Central

The measurement of sodium ion concentration in urine can provide diagnostic information and guide therapy. Unfortunately, neutral-carrier-based ion-selective electrodes show a large positive drift and loss in selectivity in undiluted urine. The extraction of electrically neutral lipids from the urine into the sensing membrane was suggested as the main source of the drift, loss of selectivity and the consequent incorrect concentration readings. In this work, (i) solvent-solvent extraction, (ii) membrane-immobilized solvent extraction, and (iii) solid phase extraction were used to remove interfering compounds from urine samples. The “cleaned” urine samples were subsequently analyzed using a calixarene (sodium ionophore X)-based, solid-contact, sodium-selective electrode in a flow-through manifold. The solid-contact sodium sensors had excellent stability in cleaned urine and an acceptable bias compared to commercial clinical analyzers.

Phillips, Feyisayo; Kaczor, Kim; Gandhi, Neel; Pendley, Bradford D.; Danish, Robert K.; Neuman, Michael R.; Toth, Blanka; Horvath, Viola; Lindner, Erno

2007-01-01

71

Identifying New Cannabis Use with Urine Creatinine-Normalized THCCOOH Concentrations and Time Intervals Between Specimen Collections*  

PubMed Central

A previously recommended a method for detecting new cannabis use with creatinine-normalized 11-nor-9-carboxy-?9-tetrahydrocannabinol (THCCOOH) urine concentrations in periodically collected specimens for treatment, workplace and judicial drug testing applications is refined by considering the time interval between urine collections. All urine specimens were collected from six less-than-daily cannabis users who smoked placebo, 1.75%, and 3.55% THC cigarettes in randomized order, each separated by one week. Ratios (n = 24,322) were calculated by dividing each creatinine-normalized THCCOOH concentration (U2) by that of a previously collected specimen (U1). Maximum, 95% limit, and median U2/U1 ratios with 15 and 6 ng THCCOOH/mL cutoff concentrations, with and without new use between specimens, were calculated for each 24-h interval after smoking up to 168 h and are included in tables. These ratios decreased with increasing interval between collections providing improved decision values for determining new cannabis use. For example, with a 15 ng THCCOOH/mL cutoff concentration and no new use between specimens, the maximum, 95% limit, and median U2/U1 ratios were 3.05, 1.59, and 0.686, respectively, when the collection interval was ? 24 h and 0.215, 0.135, and 0.085 when it was 96–119.9 h.

Smith, Michael L.; Barnes, Allan J.; Huestis, Marilyn A.

2011-01-01

72

Predicting the phenylalanine blood concentration from urine analyses. An approach to noninvasive monitoring of patients with phenylketonuria  

Microsoft Academic Search

Summary  The need for regular blood-drawing in the management of chronic metabolic disorders may negatively influence the compliance\\u000a of patients and their parents; noninvasive analytical procedures could well alleviate this burden. Using data obtained in\\u000a six adult probands with phenylketonuria, we evaluate the feasibility of noninvasive prediction of phenylalanine blood concentrations\\u000a from analysis of phenylalanine and creatinine in urine. Cross-validated regression

U. Langenbeck; F. Baum; A. Mench-Hoinowski; H. Luthe; A. W. Behbehani

2005-01-01

73

Oxygen concentration measurement in liquid lead-bismuth eutectic  

SciTech Connect

Liquid lead-bismuth (Pb-Bi) eutectic (LBE) may see extensive use as a coolant fluid, and perhaps also as a spallation target, in next generation nuclear energy systems. While it is not as reactive as alkali metal liquids, it does present a long term corrosion problem with some materials, notably stainless steels. Mitigation of the corrosion problem may be achieved by producing and maintaining a protective oxide on exposed surfaces, through control of the concentration of dissolved oxygen in the LBE. We have developed an oxygen sensor based on available zirconia-based solid electrolytes used in the automotive industry, which represents a relatively inexpensive source of reproducible and reliable components. We will present the design considerations and characteristics of our sensor unit, and describe its use in the LBE test loop at Los Alamos for measurement and control of dissolved oxygen concentration.

Darling, T. W. (Timothy W.); Li, N. (Ning)

2001-01-01

74

Blood lead concentration and biological effects in workers exposed to very low lead levels.  

PubMed

A longitudinal study was carried out on two groups of workers engaged in tin/lead alloy welding in the telecommunication sector. The risk of exposure was evaluated by measuring levels of airborne lead (PbA) and the amount of lead absorbed (PbB). The-correlated effects were assessed by determining zinc protoporphyrin (ZPP) and hemoglobin levels (Hb) and red blood cell (RBC) count. We also recorded subjective symptoms reported by workers. One group of welders composed of 365 subjects underwent two monitoring sessions performed in 1991 and 1995, respectively (Group A). A second group of welders (whose number fluctuated between 148 and 247 subjects) underwent yearly testing for 7 consecutive years (1988-1994; Group B). Results indicated a very low risk of lead exposure during microwelding operations (PbA range, 1.5-24 micrograms/m3). In fact, blood concentrations of Pb (range, 5-55, micrograms/dL) among both groups of welders were significantly higher than those in the general population in Rome (PbB range, 5-16 micrograms/dL); nevertheless, they were significantly lower than the Occupational Safety and Health Administration's permissible exposure limits ZPP determined only in Group B of welders ranged from 5 to 16 micrograms/dL (median, 22 micrograms/dL). No variation was found in the other biological parameters investigated, and no health effects were observed. During the study period, the introduction of some technological innovations led to a further reduction in Pb exposure and, subsequently, to its total elimination. PbB concentrations gradually declined to lower values (6-36 micrograms/dL), and it was interesting to note that ZPP concentrations also decreased to normal levels (range, 2-47 micrograms/dL; median, 11 micrograms/dL), demonstrating that the effect of lead on heme synthesis may occur even at very low levels of Pb exposure. PMID:9800174

Masci, O; Carelli, G; Vinci, F; Castellino, N

1998-10-01

75

Concentration of Wear Products in Hair, Blood, and Urine after Total Hip Replacement  

Microsoft Academic Search

Raised levels of cobalt and chromium are found in the blood and urine of patients with metallic total hip replacements. When one of the hip components is made of polyethylene much less metal seems to be released from the joint. The long-term effects of the accumulation of chromium in the body need to be studied further.

R. F. Coleman; J. Herrington; John T. Scales

1973-01-01

76

Chronic use of chloroquine disrupts the urine concentration mechanism by lowering cAMP levels in the inner medulla  

PubMed Central

Chloroquine, a widely used anti-malaria drug, has gained popularity for the treatment of rheumatoid arthritis, systemic lupus erythematosus (SLE), and human immunodeficiency virus (HIV). Unfortunately, chloroquine may also negatively impact renal function for patients whose fluid and electrolyte homeostasis is already compromised by diseases. Chronic administration of chloroquine also results in polyuria, which may be explained by suppression of the antidiuretic response of vasopressin. Several of the transporters responsible for concentrating urine are vasopressin-sensitive including the urea transporters UT-A1 and UT-A3, the water channel aquaporin-2 (AQP2), and the Na+-K+-2Cl? cotransporter (NKCC2). To examine the effect of chloroquine on these transporters, Sprague-Dawley rats received daily subcutaneous injections of 80 mg·kg?1·day?1 of chloroquine for 4 days. Twenty-four hour urine output was twofold higher, and urine osmolality was decreased by twofold in chloroquine-treated rats compared with controls. Urine analysis of treated rats detected the presence chloroquine as well as decreased urine urea and cAMP levels compared with control rats. Western blot analysis showed a downregulation of AQP2 and NKCC2 transporters; however, UT-A1 and UT-A3 abundances were unaffected by chloroquine treatment. Immunohistochemistry showed a marked reduction of UT-A1 and AQP2 in the apical membrane in inner medullary collecting ducts of chloroquine-treated rats. In conclusion, chloroquine-induced polyuria likely occurs as a result of lowered cAMP production. These findings suggest that chronic chloroquine treatment would exacerbate the already compromised fluid homeostasis observed in diseases like chronic kidney disease.

von Bergen, Tobias N.

2012-01-01

77

Ingestion of lead from ammunition and lead concentrations in white-tailed sea eagles (Haliaeetus albicilla) in Sweden.  

PubMed

In this study we show for the first time that lead poisoning from ammunition is a significant mortality factor for white-tailed sea eagle (WSE) (Haliaeetus albicilla) in Sweden. We analyzed 118 WSEs collected between 1981 and 2004 from which both liver and kidney samples could be taken. A total of 22% of all eagles examined had elevated (>6 microg/gd.w.) lead concentrations, indicating exposure to leaded ammunition, and 14% of the individuals had either liver or kidney lead concentrations diagnostic of lethal lead poisoning (>20 microg/gd.w.). Lead concentrations in liver and kidney were significantly correlated. In individuals with lead levels <6 microg/g, concentrations were significantly higher in kidney than in liver; in individuals with lead levels >20 microg/g, concentrations were significantly higher in liver. The lead isotope ratios indicate that the source of lead in individuals with lethal concentrations is different from that of individuals exhibiting background concentrations of lead (<6 microg/gd.w.) There were no significant sex or age differences in lead concentrations. A study from the Baltic reported in principle no biomagnification of lead, but background lead concentrations in WSE liver in this study were still four to >10 times higher than concentrations reported for Baltic fish from the same time period. In contrast to other biota there was no decrease in lead concentrations in WSE over the study period. The proportion of lead poisoned WSE remained unchanged over the study period, including two years after a partial ban of lead shot was enforced in 2002 for shallow wetlands. The use of lead in ammunition poses a threat to all raptors potentially feeding on shot game or offal. The removal of offal from shot game and alternatives to leaded ammunition needs to be implemented in order to prevent mortality from lead in raptors and scavengers. PMID:19683793

Helander, B; Axelsson, J; Borg, H; Holm, K; Bignert, A

2009-08-15

78

Effect of the Volume of Fluid Ingested on Urine Concentrating Ability During Prolonged Heavy Exercise in a Hot Environment  

PubMed Central

This study examined the effect of the volume of fluid ingested on urine concentrating ability during prolonged heavy exercise in a hot environment at low levels of dehydration. Seven healthy males performed 105 min of intermittent cycle exercise at 70% maximum oxygen uptake (32°C, 60% relative humidity) while receiving no fluid ingestion (NF), voluntary fluid ingestion (VF), partial fluid ingestion equivalent to one-half of body mass loss (PF), and full fluid ingestion equivalent to body mass loss (FF). Fluid (5°C, 3.4% carbohydrate, 10.5 mmol·L-1 sodium) was ingested just before commencing exercise and at 15, 33, 51, 69, and 87 min of exercise, and the total amount of fluid ingested in PF and FF was divided into six equal volumes. During exercise, body mass loss was 2.2 ± 0.2, 1.1 ± 0.5, 1.1 ± 0.2, and 0.1 ± 0.2% in NF, VF, PF, and FF, respectively, whereas total sweat loss was about 2% of body mass in each trial. Subjects in VF ingested 719 ± 240 ml of fluid during exercise; the volume of fluid ingested was 1.1 ± 0.4% of body mass. Creatinine clearance was significantly higher and free water clearance was significantly lower in FF than in NF during exercise. Urine flow rate during exercise decreased significantly in NF. There were significant decreases in creatinine and osmolar clearance and was a significant increase in free water clearance during exercise in NF and VF. Creatinine clearance decreased significantly and free water clearance increased significantly during exercise in PF. There was no statistical change in urinary indices of renal function during exercise in FF. The findings suggest that full fluid ingestion equivalent to body mass loss has attenuated the decline in urine concentrating ability during prolonged heavy exercise in a hot environment at low levels of dehydration. Key points During prolonged heavy exercise in a hot environment at low levels of dehydration, fluid ingestion equivalent to body mass loss results in no changes in urinary indices of renal function. Fluid ingestion equivalent to body mass loss can attenuate the decline in urine concentrating ability during exercise. Ad libitum or voluntary fluid ingestion is ineffective in reducing the decline in urine concentrating ability during exercise.

Otani, Hidenori; Kaya, Mitsuharu; Tsujita, Junzo

2013-01-01

79

Lead concentration in Hong Kong roadside dust after reduction of lead level in petrol  

SciTech Connect

Samples of roadside dust were collected from 30 sites in Hong Kong. The total concentrations of 10 metals in the samples were analyzed, and the correlation coefficients among the metal contents and the annual average daily traffic (AADT) in 1986 were determined. Pb was found to have a significant correlation (P less than 0.01) with AADT. No correlation was found between Al, Ba, Cd, Cr, Cu, Fe, Mn, Ni, and Zn with respect to AADT. A general decrease in the level of Pb in roadside dust in the past few years has been observed since the reduction in the level of lead in petrol.

Chan, G.Y.; Chui, V.W.; Wong, M.H. (Hong Kong Baptist College, Kowloon (Hong Kong))

1989-06-01

80

Evaluation of a urine screen for acetaminophen  

Microsoft Academic Search

Background  Acetaminophen (APAP) is a leading cause of fatal overdose. This study examined the performance characteristics of the Biosite\\u000a Triage TOX Drug Screen qualitative APAP urine test (urine screen) in a clinical setting.\\u000a \\u000a \\u000a \\u000a Methods  Paired urine and serum waste samples (collected within 2 hours of one another) were quantitatively analyzed for APAP concentration\\u000a and compared to the urine screen results.\\u000a \\u000a \\u000a \\u000a Results  A total

Daniel M. Ingram; George M. Bosse; Edward P. Womack; Saeed A. Jortani

2008-01-01

81

Sociodemographic and lifestyle variables are compound- and class-specific correlates of urine phytoestrogen concentrations in the U.S. population.  

PubMed

Isoflavones and lignans are plant-derived dietary compounds generally believed to be beneficial to human health. We investigated the extent to which sociodemographic (age, sex, race-ethnicity, education, and income) and lifestyle variables (smoking, alcohol consumption, BMI, physical activity, and dietary supplement use) were correlates of spot urine concentration for daidzein, genistein, O-desmethylangolensin (DMA), equol, enterodiol, and enterolactone in the U.S. population aged ? 20 y (NHANES 2003-2006). We performed correlation analyses with continuous variables and calculated stratified unadjusted geometric means for each sociodemographic and lifestyle variable. We used bivariate significance testing and covariate adjustment by use of multiple regression models to identify influential variables and used ? coefficients to estimate relative effects. Urine creatinine was also included in our analyses because of its use in correcting for variable dilution in spot urine samples. We observed many significant (P < 0.05) associations with the sociodemographic and lifestyle variables that withstood covariate adjustment. Smoking was a significant correlate of urine DMA and enterolactone, with concentrations at least 25% lower in smokers vs. nonsmokers. Consumers of 1 daily alcoholic drink vs. none were estimated to have 18-21% lower urine equol and DMA concentrations. A 25% increase in BMI was associated with a 21% lower urine enterolactone concentration, and increasing physical activity was associated with a >6% higher urine enterolactone concentration. Dietary supplement use was not significantly associated with any of the urine phytoestrogens. Overall, we found that relationships between sociodemographic and lifestyle variables and urine phytoestrogen concentration were highly compound and class specific. PMID:23596167

Rybak, Michael E; Sternberg, Maya R; Pfeiffer, Christine M

2013-04-17

82

Relationship Between 2,5-Hexanedione Concentrations in Nerve, Serum, and Urine Alone or Under Co-Treatment With Different Doses of Methyl Ethyl Ketone, Acetone, and Toluene  

Microsoft Academic Search

To ascertain the relationship among 2,5-hexanedione (2,5-HD) concentrations in nerve, serum and urine, rats were injected subcutaneously with 2.6 mmol\\/kg 2,5-HD alone, or together with 2.6 or 13.0 mmol\\/kg of methyl ethyl ketone, acetone and toluene. 2,5-HD concentrations in sciatic nerve (NC), serum (SC) and urine (UC) were determined, and the linear regression between each two of NC, SC, and

Wenyuan Zhao; Junichi Misumi; Takato Yasui; Kazuo Aoki; Takashi Kimura

1998-01-01

83

Pax transactivation-domain interacting protein is required for urine concentration and osmotolerance in collecting duct epithelia.  

PubMed

Pax transactivation-domain interacting protein (PTIP) is a widely expressed nuclear protein that is essential for early embryonic development. PTIP was first identified on the basis of its interactions with the developmental regulator Pax2 but can also bind to other nuclear transcription factors. The Pax2 protein is essential for development of the renal epithelia and for regulating the response of mature collecting ducts to hyperosmotic stress. For determination of whether PTIP also functions in more differentiated cell types, the Cre-LoxP system was used to delete the ptip gene in the renal collecting ducts using Ksp-Cre driver mice. Collecting duct-specific ptip knockout mice were viable with little discernible phenotype under normal physiologic conditions. However, collecting duct-specific ptip mutants were unable to concentrate urine after the treatment of desamino-cis, D-arginine vasopressin, an antidiuretic hormone. Furthermore, aquaporin-2 (AQP2) expression in the inner medulla of the ptip knockout mice was decreased approximately 10-fold compared with that of wild-type littermates. Expression level of tonicity responsive enhancer binding protein, a transcription factor of AQP2, is not altered in the mutant mice, but its nuclear localization in the inner medulla is unresponsive after treatment with vasopressin agonists. This was due, at least in part, to decreased expression of the arginine vasopressin receptor 2 in ptip mutants. Furthermore, ptip null inner medullary collecting duct cells were sensitive to hyperosmolality in vitro. Thus, ptip is required for the urine concentration mechanism by modulating arginine vasopressin receptor 2 and AQP2 expression in the inner medulla. The data suggest an essential role for ptip in regulating urine concentration and in controlling survival of collecting duct epithelial cells in high osmolality. PMID:17429055

Kim, Doyeob; Wang, Min; Cai, Qi; Brooks, Heddwen; Dressler, Gregory R

2007-04-11

84

Pax Transactivation-Domain Interacting Protein Is Required for Urine Concentration and Osmotolerance in Collecting Duct Epithelia  

PubMed Central

Pax transactivation-domain interacting protein (PTIP) is a widely expressed nuclear protein that is essential for early embryonic development. PTIP was first identified on the basis of its interactions with the developmental regulator Pax2 but can also bind to other nuclear transcription factors. The Pax2 protein is essential for development of the renal epithelia and for regulating the response of mature collecting ducts to hyperosmotic stress. For determination of whether PTIP also functions in more differentiated cell types, the Cre-LoxP system was used to delete the ptip gene in the renal collecting ducts using Ksp-Cre driver mice. Collecting duct–specific ptip knockout mice were viable with little discernible phenotype under normal physiologic conditions. However, collecting duct–specific ptip mutants were unable to concentrate urine after the treatment of desamino-cis, D-arginine vasopressin, an antidiuretic hormone. Furthermore, aquaporin-2 (AQP2) expression in the inner medulla of the ptip knockout mice was decreased approximately 10-fold compared with that of wild-type littermates. Expression level of tonicity responsive enhancer binding protein, a transcription factor of AQP2, is not altered in the mutant mice, but its nuclear localization in the inner medulla is unresponsive after treatment with vasopressin agonists. This was due, at least in part, to decreased expression of the arginine vasopressin receptor 2 in ptip mutants. Furthermore, ptip null inner medullary collecting duct cells were sensitive to hyperosmolality in vitro. Thus, ptip is required for the urine concentration mechanism by modulating arginine vasopressin receptor 2 and AQP2 expression in the inner medulla. The data suggest an essential role for ptip in regulating urine concentration and in controlling survival of collecting duct epithelial cells in high osmolality.

Kim, Doyeob; Wang, Min; Cai, Qi; Brooks, Heddwen; Dressler, Gregory R.

2007-01-01

85

Relaxin concentrations in serum and urine of endangered and crazy mixed-up species.  

PubMed

The human population explosion has pushed many mammalian wildlife species to the brink of extinction. Conservationists are increasingly turning to captive breeding as a means of preserving the gene pool. We previously reported that serum immunoactive relaxin provided a reliable means of distinguishing between true and pseudopregnancy in domestic dogs, and this method has since been found to be a reliable indicator of true pregnancy in endangered Asian and African elephants and Sumatran rhinoceroses. Our canine relaxin radioimmunoassay (RIA) has now been adapted and validated to measure relaxin in the serum and urine of felids, including domestic and wild species. Moreover, a commercially available canine serum relaxin kit (Witness) Relaxin Kit; Synbiotics, San Diego, CA), has been adapted for reliable detection of relaxin in urine of some felid species. Our porcine relaxin RIA has also been utilized to investigate the role of relaxin in reproductive processes of the spotted hyena, a species in which the female fetuses are severely masculinized in utero. Indeed, this species might well now be extinct were it not for the timely secretion of relaxin to enable copulation and birth of young through the clitoris. Additional studies have suggested relaxin may be a useful marker of pregnancy in the northern fur seal and the maned wolf (the former species has been designated as "depleted" and the latter as "near threatened"). Given appropriate immunoassay reagents, relaxin determination in body fluids thus provides a powerful tool for conservationists and biologists investigating reproduction in a wide variety of endangered and exotic species. PMID:19416182

Steinetz, B; Lasano, S; de Haas van Dorsser, F; Glickman, S; Bergfelt, D; Santymire, R; Songsassen, N; Swanson, W

2009-04-01

86

Declines in blood lead concentrations in clinically affected and unaffected cattle accidentally exposed to lead.  

PubMed

Lead (Pb) poisoning remains a common cause of morbidity in dairy and beef cattle. Although Pb toxicosis is typically diagnosed in cattle with clinical signs of acute or subacute Pb poisoning, it has been hypothesized that subclinical chronic exposure of cattle to Pb, which often goes undiagnosed, poses more of a risk to the human consumer. There is not adequate information on Pb kinetics to determine when or if Pb-exposed cattle can safely enter the food chain. The objectives of the current study were to determine whether subclinical elevations in blood Pb (bPb) were present in cattle from herds where 1 or more individuals had clinical Pb poisoning and to determine the half-life (t(1/2)) of bPb in Pb-exposed cattle. Samples of blood were collected and analyzed for Pb from 126 cattle from 9 farms. Blood lead concentrations ranged from below the detection limit (2.50 µg/dl) to 423.0 µg/dl. Only 11 of the 94 cattle with detectable bPb had clinical signs such as diarrhea, blindness, bruxism, or seizures. When possible, cattle with detectable bPb had serial samples taken. The mean t(1/2) calculated from 44 serially sampled cattle was 135 days (standard deviation: 125 days, range: 3-577 days). A source of Pb on the farm was determined for all but one herd. PMID:22362951

Bischoff, Karyn; Thompson, Belinda; Erb, Hollis N; Higgins, William P; Ebel, Joseph G; Hillebrandt, Joseph R

2011-12-06

87

Interaction between vasopressin and angiotensin II in vivo and in vitro: effect on aquaporins and urine concentration.  

PubMed

The study was undertaken to examine the potential cross talk between vasopressin and angiotensin II (ANG II) intracellular signaling pathways. We investigated in vivo and in vitro whether vasopressin-induced water reabsorption could be attenuated by ANG II AT1 receptor blockade (losartan). On a low-sodium diet (0.5 meq/day) dDAVP-treated animals with or without losartan exhibited comparable renal function [creatinine clearance 1.2 +/- 0.1 in dDAVP+losartan (LSDL) vs. 1.1 +/- 0.1 ml.100 g(-1).day(-1) in dDAVP alone (LSD), P > 0.05] and renal blood flow (6.3 +/- 0.5 in LSDL vs. 6.8 +/- 0.5 ml/min in LSD, P > 0.05). The urine output, however, was significantly increased in LSDL (2.5 +/- 0.2 vs. 1.8 +/- 0.2 ml.100 g(-1).day(-1), P < 0.05) in association with decreased urine osmolality (2,600 +/- 83 vs. 3,256 +/- 110 mosmol/kgH(2)O, P < 0.001) compared with rats in LSD. Immunoblotting revealed significantly decreased expression of medullary AQP2 (146 +/- 6 vs. 176 +/- 10% in LSD, P < 0.01), p-AQP2 (177 +/- 13 vs. 214 +/- 12% in LSD, P < 0.05), and AQP3 (134 +/- 14 vs. 177 +/- 11% in LSD, P < 0.05) in LSDL compared with LSD. The expressions of AQP1, the alpha(1)- and gamma-subunits of Na-K-ATPase, and the Na-K-2Cl cotransporter were not different among groups. In vitro studies showed that ANG II or dDAVP treatment was associated with increased AQP2 expression and cAMP levels, which were potentiated by cotreatment with ANG II and dDAVP and were inhibited by AT1 blockade. In conclusion, ANG II AT1 receptor blockade in dDAVP-treated rats on a low-salt diet was associated with decreased urine concentration and decreased inner medullary AQP2, p-AQP2, and AQP3 expression, suggesting that AT1 receptor activation plays a significant role in regulating aquaporin expression and modulating urine concentration in vivo. Studies in collecting duct cells were confirmatory. PMID:20576679

Wang, Weidong; Li, Chunling; Summer, Sandra; Falk, Sandor; Schrier, Robert W

2010-06-24

88

Concentrations of lead in cosmetics commonly used in South Africa  

Microsoft Academic Search

In this study, we present evidence of lead in lip liner, oil absorbent powder, mascara, concealer, lipsticks, lip gloss, and foundation. The samples were analyzed for lead by flame atomic absorption spectrometry. The levels of lead in concealer, mascara, lip liner, and oil absorbent powder were found to be 7.4?±?1.3?µg?g, 15.8?±?0.2?µg?g, 29.0?±?9.2?µg?g, and 17.3?±?2.9?µg?g, respectively. The levels of lead in

J. D. O. Brandão; O. J. Okonkwo; M. Sehkula; R. M. Raseleka

2011-01-01

89

Concentrations of lead in cosmetics commonly used in South Africa  

Microsoft Academic Search

In this study, we present evidence of lead in lip liner, oil absorbent powder, mascara, concealer, lipsticks, lip gloss, and foundation. The samples were analyzed for lead by flame atomic absorption spectrometry. The levels of lead in concealer, mascara, lip liner, and oil absorbent powder were found to be 7.4?±?1.3?µg?g, 15.8?±?0.2?µg?g, 29.0?±?9.2?µg?g, and 17.3?±?2.9?µg?g, respectively. The levels of lead in

J. D. O. Brandão; O. J. Okonkwo; M. Sehkula; R. M. Raseleka

2012-01-01

90

Quantitative mass spectrometric determination of methylphenidate concentration in urine using an electrospray ionization source integrated with a polymer microchip.  

PubMed

We have demonstrated the use of a simple microfabricated electrospray ionization source for coupling microfluidic chips to mass spectrometry (MS). A polymer-based microchip, coupled to a triple quadrupole mass spectrometer, has been employed for direct infusion quantitative bioanalysis of methylphenidate (Ritalin) extracted from human urine samples. The approach used a microfabricated polymer electrospray emitter to couple a microfluidic channel to a stable electrospray ionization source. The microchip was fabricated from cycloolefin plastic plate by hot embossing and thermal bonding. This microfluidic chip contained two independent microfluidic channels, integrated with two corresponding electrospray emitters and an internal gold electrode. Liquid-liquid extraction was used to prepare urine samples, spiked with methylphenidate. A trideuterated analogue of methylphenidate (methylphenidate-d(3)) was used as the internal standard for the analysis. The system showed good electrospray stability and reproducibility with different spray tips. Four different electrospray tips were used to analyze the same sample, and the results showed very small variation with a relative standard deviation of 1.4%. A standard curve prepared for methylphenidate in urine (R(2) = 0.999) was linear over the range of 0.4-800 ng/mL. The precision of the quality control samples for three different concentrations ranged from 19.1% at 20 ng/mL, 3.2% at 200 ng/mL, to 3.5% at 667 ng/mL while the accuracy was 96.3% at 20 ng/mL, 101.2% at 200 ng/mL, and 101.6% at 667 ng/mL. No system carryover was detected even when the same device was used for sequential analysis. These results suggest the potential of this microdevice for MS-based quantitative analysis in drug discovery and development. PMID:15117199

Yang, Yanou; Kameoka, Jun; Wachs, Timothy; Henion, Jack D; Craighead, H G

2004-05-01

91

Airborne Lead Concentrations and the Effect of Reductions in the Lead Content of Petrol,  

National Technical Information Service (NTIS)

Lead in petrol is the major source of airborne lead in the United Kingdom. On 1 January 1986 the maximum permissible lead content of petrol was reduced from 0.4 to 0.15 grams per litre. The report assesses the results available from 21 airborne lead monit...

G. McInnes

1986-01-01

92

Tooth lead concentration as an indicator for environmental lead pollution in Agra City, India  

Microsoft Academic Search

Agra ( India ), the city of Taj Mahal, is receiving keen attention of environmentalists on the problem of escalating environmental pollution. The increase in dis-semination of lead in to the environment from stationary as well as mobile sources has resulted in a widespread lead exposure. The continued use of leaded gasoline and lead based paint in India is the

M. M. Srivastava; Shalini Srivastava; Anup Vaid

1992-01-01

93

The temporal variations of lead concentration in a freshwater lake  

Microsoft Academic Search

The temporal and spatial variations in the Pb concentration of a freshwater recreational lake were determined, and the results compared with daily records of lake volume, residence time and number of boats launched. In addition, laboratory studies were carried out to establish the influence of sediment-water interactions on the Pb concentration of the lake water. The variation in the Pb

James E. Byrd; Michael J. Perona

1980-01-01

94

IONIC AND OSMOTIC CONCENTRATIONS IN BLOOD AND URINE OF PACHYGRAPSUS CRASSIPES ACCLIMATED TO DIFFERENT SALINITIES  

Microsoft Academic Search

In its normal medium of sea water the blood of Pachygrapsus may be slightly hypo-osmotic (Jones, 1941 ; Robertson, 1953) . In a dilute sea water the blood concentration declines somewhat but is maintained higher than the concentration of the medium (Jones, 1941 ) and this hyper-osmotic regulation permits the crab to enter regions of brackish water. In a more

C. LADD PROSSER; JAMES W. GREEN

95

Electrothermal atomization atomic absorption spectrometry for the determination of lead in urine: results of an interlaboratory study 1 This paper was published in the Special Issue of the Third European Furnace Symposium, Prague, Czech Republic, June 1998. 1  

Microsoft Academic Search

Results of an interlaboratory study are reported for the determination of lead in urine. Two levels of a lyophilized material containing biologically-bound lead were prepared using pooled urine obtained from lead-poisoned children undergoing the CaNa2EDTA mobilization test. The materials were circulated to a group of reference laboratories that participate in the `New York State Proficiency Testing Program for Blood Lead'.

Patrick J Parsons; Walter Slavin

1999-01-01

96

Concentration of Uranium and Lead and the Isotopic Composition of Lead in Meteoritic Material  

Microsoft Academic Search

The cosmic abundance of lead and uranium have been determined by studying the lead and uranium contents of meteoritic materials. Lead is found to be present to 8×10-3 atom\\/10 000 atoms of silicon, and uranium to 1×10-4 atom\\/10 000 atom of silicon. The new value for lead removes the hump in the cosmic abundance curve in the 206-208 mass region.

C. Patterson; H. Brown; G. Tilton; M. Inghram

1953-01-01

97

Concentrations of Gatifloxacin in Plasma and Urine and Penetration into Prostatic and Seminal Fluid, Ejaculate, and Sperm Cells after Single Oral Administrations of 400 Milligrams to Volunteers  

Microsoft Academic Search

Gatifloxacin (GTX), a new fluoroquinolone with extended antibacterial activity, is an interesting candidate for the treatment of chronic bacterial prostatitis (CBP). Besides the antibacterial spectrum, the concentrations in the target tissues and fluids are crucial for the treatment of CBP. Thus, it was of interest to investigate its penetration into prostatic and seminal fluid. GTX concentrations in plasma, urine, ejaculate,

CHRISTOPH K. NABER; MICHAELA STEGHAFNER; MARTINA KINZIG-SCHIPPERS; CHRISTIAN SAUBER; FRITZ SORGEL; HANS-JURGEN STAHLBERG; KURT G. NABER

2001-01-01

98

Lead concentrations in blood and milk from periparturient dairy heifers seven months after an episode of acute lead toxicosis  

SciTech Connect

In September 1988, 100 of 300 yearling dairy heifers developed blindness, tachypnea, foaming at the mouth, chewing, and facial fasciculations. Twenty-five animals died. Lead toxicosis was diagnosed based on the clinical signs and the presence of excessive concentrations of lead in whole blood, liver, kidney, and rumen contents of affected animals. The source of the lead was sudan grass silage that had been contaminated by soil that contained up to 77,000 mg/kg of lead. Lead concentrations were determined approximately 7 months after the acute episode of lead toxicosis. Whole blood and milk samples were obtained from heifers and a group of control cows 2 weeks prior to (blood only), at the time of, and 2 and 4 weeks after freshening. No lead was found in any of the milk samples (detection limit = 0.055 mg/liter). Animals that had been severely affected by lead toxicosis experienced a transient increase in whole blood lead concentrations at freshening that was not high enough to be considered toxic. No similar increases in blood lead were observed for control cows or heifers that had experienced milder toxicosis. These findings suggest that at parturition lead is mobilized into the blood of cattle previously exposed to excessive lead.

Galey, F.D.; Slenning, B.D.; Anderson, M.L.; Breneman, P.C.; Littlefield, E.S.; Melton, L.A.; Tracy, M.L. (California Veterinary Diagnostic Laboratory System-Toxicology Laboratory, University of California, Davis (USA))

1990-07-01

99

Renal Manifestations of Leprosy: Impaired Acidification and Concentration of Urine in Patients with Leprosy.  

National Technical Information Service (NTIS)

A variety of diseases, sharing only hypergammaglobulinemia in common, are associated with impaired urinary-concentrating ability and with impaired acidification after acid-loading. Forty-seven patients with leprosy were studied to determine whether or not...

R. A. Gutman W. H. Lu D. J. Drutz

1972-01-01

100

Optimal transport parameters of the inner medullary collecting duct in interaction between urine concentrating and urea excreting mechanisms: a computer simulation study.  

PubMed

Although the accumulation of urea in the renal medulla is essential for the formation of concentrated urine, it is also necessary for the kidney to excrete considerable amounts of urea into the urine as a waste product of protein degradation. Thus, the urine concentrating capacity is attained by the interaction with the efficiency of urea excretion. To seek the best condition for this phenomenon, we developed an objective function for evaluating urea excreting capacity relative to urine concentrating capacity by using a mathematical model consisting of components of the countercurrent multiplication system: the ascending thin limb, capillary network, and inner medullary collecting duct. The values of the objective functions were calculated as three-dimensional functions of transport parameters for the inner medullary collecting duct, including hydraulic conductivity, urea permeability, and reflection coefficient for urea. The results of the computer analysis revealed that the maximum value of the objective function was attained when values for transport parameters of the inner medullary collecting duct corresponded to those experimentally obtained values reported previously. We conclude that the maximum urine concentrating capacity is limited by the efficiency of urea excreting capacity of the kidney, and vice versa. PMID:8938688

Hamada, Y; Taniguchi, J; Imai, M

1996-01-01

101

Methods for Measuring Lead Concentrations in Paint Films.  

National Technical Information Service (NTIS)

Recent legislation required the U.S. Department of Housing and Urban Development (HUD) to establish procedures to abate lead-based paint in existing HUD-assisted housing. The legislation also required HUD to assess the accuracy, precision, reliability, an...

M. E. McKnight W. E. Byrd W. E. Roberts E. S. Lagergren

1989-01-01

102

Lead and cadmium concentrations in livestock bred in campania, Italy  

Microsoft Academic Search

Among the various aspects of environmental pollution, special attention must be directed to heavy metals, which show a remarkable tendency to accumulate in tissues and organs of animals and humans. Particularly, lead and cadmium are of great concern when one considers that the variety of their uses has increased their level in the environment and that they have been identified

Renata Amodio-Cocchieri; Patrizio Fiore

1987-01-01

103

Elimination of matrix and spectral interferences in the measurement of lead and cadmium in urine and blood by electrothermal atomic absorption spectrometry with deuterium background correction  

SciTech Connect

Direct measurement of lead and cadmium in blood and urine by electrothermal atomic absorption spectrometry with deuterium background correction (D2-AAS) is prone to severe matrix and spectral interferences. The authors overcame these effects by coating the L'vov platform with ammonium molybdate, reducing the atomization time, introducing a post-atomization cooling step, carefully selecting ashing and atomization temperatures, and using an appropriate procedure for matrix modification. To determine Pb and Cd in blood and urine, they used matrix-matched calibration curves. With the proposed procedure for sample preparation, both Pb and Cd in whole blood can be determined in the same diluted sample. Results obtained by D2-AAS correlate closely with those by Zeeman-corrected AAS. Detection limits (mean blank + 3 SDblank) for Pb in urine and blood were 4 micrograms/L. For cadmium, the detection limits were 0.4 and 0.1 micrograms/L for urine and blood analysis, respectively. Between-run CVs were less than 5.0%.

D'Haese, P.C.; Lamberts, L.V.; Liang, L.; Van de Vyver, F.L.; De Broe, M.E. (University of Antwerp, Department of Nephrology-Hypertension (Belgium))

1991-09-01

104

Reduction of lead concentrations in vegetables grown in Tarragona Province, Spain, as a consequence of reduction of lead in gasoline  

SciTech Connect

Lead concentrations were determined in 350 samples belonging to 13 different species of vegetables from Tarragona Province, Spain. The samples were subjected to lead analyses by graphite furnace atomic absorption spectrophotometry. During the period 1989-1994, an average decrease for lead concentrations of 69% was estimated. Spinach showed the lowest reduction2 in lead content (6%), while the highest decreases were observed for onion (87%) and leek (90%). Taking into account the average consumption of vegetable foodstuffs by the population of Tarragona Province, the daily lead intake through edible vegetables was reduced from 41.5 {mu}g/d in 1989 to 10.6 {mu}g/d in 1994. The results of the current study demonstrate a substantial decline in the lead levels of vegetables from Tarragona Province. The major cause of this decline is most likely the reduced leaded gasoline consumption.

Belles, M.; Rico, A.; Schuhmacher, M. [Rovira i Virgili Univ., Reus (Spain)] [and others

1995-12-31

105

Concentration distribution of the marijuana metabolite Delta9-tetrahydrocannabinol-9-carboxylic acid and the cocaine metabolite benzoylecgonine in the department of defense urine drug-testing program.  

PubMed

Urine drug testing has been employed for punitive purposes by the Department of Defense since December 1981 (Memorandum 62884, Deputy Secretary of Defense Frank C. Carlucci). Federal Workplace Drug Testing Programs were initiated in response to Executive Order 12564 issued on September 15, 1986, that required Drug-Free Federal Workplaces be established. In their respective programs, a positive urine drug test may be referred to a military court martial or to an administrative board. To address safety and insurance requirements, the testing of civilians has expanded beyond Federal Programs to include pre-employment and post-accident urine drug testing. During adjudication, an Expert Toxicologist may be asked to opine what can be discerned from the concentration of drug or drug metabolite found in the urine. Little can be opined with certainty from a positive urine drug test as to the amount of drug ingested, when the drug was ingested, and in most instances, whether the individual felt the effects of the drug, or was under the influence of the drug found in the urine. What may be useful to both the Expert and to the Trier-of-Facts is the frequency that a particular urine drug concentration is encountered in positive drug tests. The finding that 50% of all positive marijuana and cocaine urine metabolite concentrations in the military testing program over the three-year period of October 1, 2004 through September 30, 2007, are below a median value of 65 and 968 ng/mL, respectively, provide reference points. A median drug concentration combined with the percentile or frequency that a particular urine drug concentration occurs may provide evaluative information for a determination of the facts and the outcome of judicial or administrative proceedings. This may be especially useful to jurors when the concentration of marijuana or cocaine metabolite is perceptibly low. The information would also be applicable to medical review officers, medical examiners, drug treatment professionals, probation officers, and program analysts coordinating drug policy decisions. PMID:18652746

Jemionek, John F; Copley, Curtis L; Smith, Michael L; Past, Marilyn R

106

Concentrations of cadmium and lead in different types of milk  

Microsoft Academic Search

Concentrations of Pb and Cd were determined in samples of human, raw and pasteurized cow's and goat's milk and powdered infant\\u000a formula. The following mean Cd concentrations (and ranges) were recorded: in human milk, 2.70??g\\/l (0.6–11.3, n=55); in raw cow's milk, 4.88??g\\/l (0.7–23.1, n=47); in pasteurized cow's milk, 4.30??g\\/l (3.4–5.9, n=6); in goat's milk, 7.81??g\\/l (1.0–18.4, n=38); and in powdered,

E. M. Rodríguez Rodríguez; E. Delgado Uretra; C. Díaz Romero

1999-01-01

107

Lead and cadmium concentrations in livestock bred in Campania, Italy  

SciTech Connect

Among the various aspects of environmental pollution, special attention must be directed to heavy metals, which show a remarkable tendency to accumulate in tissues and organs of animals and humans. Particularly, lead and cadmium are of great concern when one considers that the variety of their uses has increased their level in the environment and that they have been identified as the causes of several clinical problems. Since heavy metals may be used as indicators of industrial contamination, the Italian Ministry of Health started a research program concerning the lead and cadmium levels in meat, cow's milk and eggs produce by Italian livestock and in well water, and in local and industrial feeds tuffs employed in their breeding. This is the object of the present study carried out in the Campania province.

Amodio-Cocchieri, R.; Fiore, P.

1987-09-01

108

Breast milk lead concentrations of mothers living near tin smelters.  

PubMed

We compared Pb concentration in human milk from 37 mothers living in a neighborhood of tin-ore smelters to that from 45 mothers living in a fishing community. The median breast-milk-Pb (BM-Pb) concentration was significantly (p = 0.0000001) higher (11.3 ?g L(-1); ?0.96-29.4 ?g L(-1)) in mothers living in the vicinity of smelters than that of rural mothers (1.9 ?g L(-1); ?0.96-20.0 ?g L(-1)). These mothers also showed a statistically significant correlation between length of residence and BM-Pb concentration (Spearman r = 0.6864; p < 0.0001). The estimated median exposure (for infants <6 months) was 3.0 ?g kg(-1) b.w. for rural infants compared to 7.5 ?g kg(-1) b.w. for infants in the vicinity of metal smelters. Overall, most BM-Pb concentrations (79 %) in the metal smelter area were above the critical limit of 5.0 ?g L(-1) set by the WHO. PMID:24068462

Marques, Rejane C; Moreira, Maria de Fátima R; Bernardi, José Vicente E; Dórea, José G

2013-09-26

109

Iodine concentrations in porcine blood, urine, and tissues after a single dose of iodised oil  

Microsoft Academic Search

Experimental groups of pigs were treated orally with 120 mg (Group O 120), or 480 mg (Group O 480) of iodine per animal, or intramuscularly with 240 mg (Group I 240) of iodine per animal. Iodine was administered in the form of iodised fatty acid esters (IFAE). The treatment resulted in significantly increased iodine concentrations in tissues and a single

I. HERZIG; B. PÍSA?ÍKOVÁ; I. DIBLÍKOVÁ; P. SUCHÝ

2001-01-01

110

Is citrate an inhibitor of calcium oxalate crystal growth in high concentrations of urine?  

Microsoft Academic Search

The effect of citrate on calcium oxalate (CaOx) crystal growth was studied in a system in which series of samples containing [45Ca]calcium chloride were brought to different levels of supersaturation with various concentrations of oxalate. The crystallization was assessed by measuring the amount of isotope remaining in solution 30 min after the addition of CaOx seed crystals to samples containing

H. Bek-Jensen; A.-M. Fornander; M.-A. Nilsson; H.-G. Tiselius

1996-01-01

111

Selenocompounds in juvenile white sturgeon: evaluating blood, tissue, and urine selenium concentrations after a single oral dose.  

PubMed

Selenium (Se) is an essential micronutrient for all vertebrates, however, at environmental relevant levels, it is a potent toxin. In the San Francisco Bay-Delta, white sturgeon, an ancient Chondrostean fish of high ecological and economic value, is at risk to Se exposure. The present study is the first to examine the uptake, distribution, and excretion of various selenocompounds in white sturgeon. A combined technique of stomach intubation, dorsal aorta cannulation, and urinary catheterization was utilized, in this study, to characterize the short-term effects of Se in the forms of sodium-selenate (Selenate), sodium-selenite (Selenite), selenocystine (SeCys), l-selenomethionine (SeMet), Se-methylseleno-l-cysteine (MSeCys), and selenoyeast (SeYeast). An ecologically relevant dose of Se (?500 ?g/kg body weight) was intubated into groups of 5 juvenile white sturgeon. Blood and urine samples were repeatedly collected over the 48 h post intubation period and fish were sacrificed for Se tissue concentration and distribution at 48 h. The tissue concentration and distribution, blood concentrations, and urinary elimination of Se significantly differ (p ? 0.05) among forms. In general, organic selenocompounds maintain higher blood concentrations, with SeMeCys maintaining the highest area under the curve (66.3 ± 8.7 and 9.3 ± 1.0 ?g h/ml) and maximum Se concentration in blood (2.3 ± 0.2 and 0.4 ± 0.2 ?g/ml) in both the protein and non-protein bound fractions, respectively. Selenate, however, did not result in significant increase of Se concentration, compared with the control, in the protein-bound blood fraction. Regardless of source, Se is preferentially distributed into metabolically active tissues, with the SeMet treated fish achieving the highest concentration in most tissues. In contrast, Selenite has very similar blood concentrations and tissue distribution profile to SeCys and SeYeast. From blood and tissue Se concentrations, Selenate is not stored in blood, but taken up rapidly by the liver and white muscle. Urinary elimination of Se is form dependent and peaks between 3 and 12 h post intubation. A basic understanding of the overall Se absorption, distribution, and elimination is provided through monitoring tissue Se concentrations, however, conclusions regarding to the dynamics and the specific processes of Se metabolism can only be inferred, in the absence of kinetic information. PMID:22226619

Huang, Susie Shih-Yin; Strathe, Anders Bjerring; Wang, Wei-Fang; Deng, Dong-Fang; Fadel, James G; Hung, Silas S O

2011-12-16

112

Uptake and transport of lead by perennial ryegrass from flowing solution culture with a controlled concentration of lead  

Microsoft Academic Search

Summary  Perennial ryegrass was grown in flowing solution culture in a glasshouse, and during February lead was added to the nutrient\\u000a solution and held at a constant concentration; uptake and transport of lead were followed in conditions of low intensity daylight\\u000a or higher intensity artificial light. Uptake of lead by the roots was most rapid during the first 4 days after

S. C. Jarvis; L. H. P. Jones; C. R. Clement

1977-01-01

113

Urine electrolytes and the urine anion and osmolar gaps  

Microsoft Academic Search

Urine ammonia concentration is crucial to understanding and quantifying the kidney's response to metabolic acidosis. This test is generally not performed by clinical laboratories. The urine anion gap and osmolar gaps have been proposed as surrogate measures of urine ammonia in patients with hyperchloremic acidosis. We measured ammonium and other electrolytes in the urine of patients attending our renal disease

Barry Kirschbaum; Domenic Sica; F. Phillip Anderson

1999-01-01

114

Blood lead concentration, renal function, and blood pressure in London civil servants  

Microsoft Academic Search

Blood lead concentration was measured in 398 male and 133 female London civil servants not subject to industrial exposure to heavy metals. The relation between blood lead and serum creatinine concentrations and blood pressure were examined. Blood lead concentration ranged from 0.20 to 1.70 mumol\\/l with a geometric mean concentrations of 0.58 mumol\\/l in men and 0.46 mumol\\/l in women

J Staessen; W B Yeoman; A E Fletcher; H L Markowe; M G Marmot; G Rose; A Semmence; M J Shipley; C J Bulpitt

1990-01-01

115

Population variability of phthalate metabolites and bisphenol A concentrations in spot urine samples versus 24- or 48-h collections.  

PubMed

Human exposure to phthalates and bisphenol A (BPA) can be assessed through urinary biomonitoring, but methods to infer daily intakes assume that spot sample concentrations are comparable to daily average concentrations. We evaluate this assumption using human biomonitoring data from Germany and the United States (US). The German data comprised three regional studies with spot samples and one with full-day samples analyzed for phthalate metabolites. The US data included: a study on DEHP metabolites and BPA involving eight persons supplying all urine voids (from which 24-h samples were constructed) for seven consecutive days; NHANES spot sample data on DEHP metabolites and BPA; and a regional study of children with 48-h samples analyzed for BPA. In the German data, measures of central tendency differed, but spot and 24-h samples showed generally comparable variance including 95th percentiles and maxima equidistant from central tendency measures. In contrast, the US adult data from the eight-person study showed similar central tendencies for phthalate metabolites and BPA, but generally greater variability for the spot samples, including higher 95th percentiles and maxima. When comparing children's BPA concentrations in NHANES spot and 48-h samples, distributions showed similar central tendency and variability. Overall, spot urinary concentrations of DEHP metabolites and BPA have variability roughly comparable with corresponding 24-h average concentrations obtained from a comparable population, suggesting that spot samples can be used to characterize population distributions of intakes. However, the analysis also suggests that caution should be exercised when interpreting the high end of spot sample data sets. PMID:22669498

Christensen, Krista L Yorita; Lorber, Matthew; Koch, Holger M; Kolossa-Gehring, Marike; Morgan, Marsha K

2012-06-06

116

Modification of screening immunoassays to detect sub-threshold concentrations of cocaine, cannabinoids, and opiates in urine: use for detecting maternal and neonatal drug exposures.  

PubMed

Testing for drugs of abuse in urine is commonplace in emergency departments and neonatal units. However, the clinical sensitivity of immunochemical screening methods is limited by the threshold concentrations used to distinguish between positive and negative specimens. Immunochemical screening methods for cocaine metabolite (benzoylecgonine), cannabinoids, and opiates in urine were recalibrated to detect drugs at lower threshold concentrations. The precision and linearity of the signals at the modified thresholds were verified by diluting drug-positive urine specimens to concentrations below the conventional cutoff concentration and measuring the rate signals in triplicate. To assess the clinical performance of the modified methods, specimens that tested negative using the unmodified assays were re-screened at the lower threshold, and specimens that re-screened positive were submitted for gas chromatographic/mass spectrometric (GC/MS) confirmation. Reproducibility of sub-threshold measurements was comparable to the unmodified assays, and rate separations between successive dilutions were sufficient to give semi-quantitative results. Using the lower thresholds, drugs were detected in 4-5% of the subjects that had screened negative at the conventional threshold concentration. GC/MS analysis confirmed the presence of cannabinoids and cocaine metabolite in 74% and 84%, respectively, of urine specimens that re-screened positive. Morphine, codeine, hydromorphone, or hydrocodone was detected by GC/MS analysis in 31% of opiate-positive re-screens. PMID:10678589

Hattab, E M; Goldberger, B A; Johannsen, L M; Kindland, P W; Ticino, F; Chronister, C W; Bertholf, R L

2000-01-01

117

Investigation of Higher Than Standard Lead Concentrations in Drinking Water From Washington, D.C  

Microsoft Academic Search

For over two years, the Washington, D.C. area has been plagued by the incidence of alarming concentrations of lead found in local drinking water. During this period, water with lead concentration levels above the U.S. Environmental Protection Agency's (EPA) action limit of 15 ppb has been found in approximately 66% of the homes tested. Because of the problems with lead

N. E. Adarkwah; I. Ararso; N. Garcia; A. Goldman; C. Lieu; J. Mondragon; V. Swamy; M. Unigarro; K. Cuff

2005-01-01

118

Acute changes in arginine vasopressin, sweat, urine and serum sodium concentrations in exercising humans: does a coordinated homeostatic relationship exist?  

Microsoft Academic Search

The parallel response of sweat rate and urine production to changes in plasma osmolality and volume support a role for arginine vasopressin (AVP) as the main endocrine regulator of both excretions. A maximal test to exhaustion and a steady-state run on a motorised treadmill were both completed by 10 moderately trained runners, 1 week apart. Sweat, urine and serum sodium

T. Hew-Butler; T. D. Noakes; S. J. Soldin; J. G. Verbalis

2010-01-01

119

Blood and urinary bisphenol A concentrations in children, adults, and pregnant women from china: partitioning between blood and urine and maternal and fetal cord blood.  

PubMed

Limited information exists on exposure to bisphenol A (BPA) by children, adults, and pregnant women in China. In the present study, we determined BPA concentrations in whole blood collected from 10 children (1-5 years), 40 women (30 pregnant and 10 nonpregnant), and 30 fetuses (i.e., cord blood). Further, to evaluate the relationship between urinary and blood BPA concentrations, paired specimens of blood and urine (n = 50 pairs) were collected from an adult population. BPA was found in 46% of all blood samples analyzed, with a geometric mean (GM) concentration of 0.19 ng/mL. BPA was found in 84% of urine samples from adults, with a GM concentration of 1.01 ng/mL [0.48 ?g/g creatinine (Cr)]. Gender and age were not good predictors of blood BPA concentrations. However, we did find that the creatinine-adjusted urinary BPA concentrations in females were significantly higher (p < 0.05) than the concentrations found in males and that the blood BPA concentrations in children were significantly higher (p < 0.05) than the concentrations found in adults. Among all adults, unadjusted urinary BPA concentrations (i.e., volume-based) were inversely (r = -0.312, p < 0.05) correlated with age when an outlier value (8.70 ng/mL) was excluded from analysis. Concentrations of BPA in urine (creatinine-adjusted) and blood were significantly correlated (r = 0.571, p < 0.01), with concentrations measured in urine approximately an order of magnitude higher than the concentrations found in blood. The mean and GM values for ratios of concentration of BPA between blood and urine were 0.109 and 0.057, respectively. The ratio of mean concentrations of BPA between cord blood and maternal blood was 0.108. On the basis of urinary BPA levels, we estimated the total daily intake (EDI) of BPA by Chinese adults. The mean (range) EDIs of BPA by adult males and females in China were 0.041 (<0.005-0.224) and 0.048 (<0.005-0.151) ug/kg bw/day, respectively. The pregnant women who underwent intravenous drug administration immediately before delivery had significantly higher concentrations of BPA in their blood than did those who did not receive intravenous drug administration. This is the first study to document the occurrence of and human exposure to BPA by pregnant women and fetuses from China. PMID:23506159

Zhang, Tao; Sun, Hongwen; Kannan, Kurunthachalam

2013-04-04

120

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

PubMed

Lead poisoning is a primary factor impeding the survival and recovery of the critically endangered California Condor (Gymnogyps californianus). However, the frequency and magnitude of lead exposure in condors is not well-known in part because most blood lead monitoring occurs biannually, and biannual blood samples capture only approximately 10% of a bird's annual exposure history. We investigated the use of growing feathers from free-flying condors in California to establish a bird's lead exposure history. We show that lead concentration and stable lead isotopic composition analyses of sequential feather sections and concurrently collected blood samples provided a comprehensive history of lead exposure over the 2-4 month period of feather growth. Feather analyses identified exposure events not evident from blood monitoring efforts, and by fitting an empirically derived timeline to actively growing feathers, we were able to estimate the time frame for specific lead exposure events. Our results demonstrate the utility of using sequentially sampled feathers to reconstruct lead exposure history. Since exposure risk in individuals is one determinant of population health, our findings should increase the understanding of population-level effects from lead poisoning in condors; this information may also be helpful for other avian species potentially impacted by lead poisoning. PMID:20199067

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

2010-04-01

121

Concentrations of delta9-tetrahydrocannabinol and 11-nor-9-carboxytetrahydrocannabinol in blood and urine after passive exposure to Cannabis smoke in a coffee shop.  

PubMed

Cannabinoid concentrations in blood and urine after passive exposure to cannabis smoke under real-life conditions were investigated in this study. Eight healthy volunteers were exposed to cannabis smoke for 3 h in a well-attended coffee shop in Maastricht, Netherlands. An initial blood and urine sample was taken from each volunteer before exposure. Blood samples were taken 1.5, 3.5, 6, and 14 h after start of initial exposure, and urine samples were taken after 3.5, 6, 14, 36, 60, and 84 h. The samples were subjected to immunoassay screening for cannabinoids and analyzed using gas chromatography-mass spectrometry (GC-MS) for Delta(9)-tetrahydrocannabinol (THC), 11-nor-hydroxy-Delta(9)-tetrahydrocannabinol (THC-OH), and 11-nor-9-carboxy-Delta(9)-tetrahydrocannabinol (THC-COOH). It could be demonstrated that all volunteers absorbed THC. However, the detected concentrations were rather small. None of the urine samples produced immunoassay results above the cutoff concentration of 25 ng/mL. THC-COOH concentrations up to 5.0 and 7.8 ng/mL before and after hydrolysis, respectively, were found in the quantitative GC-MS analysis of urine. THC could be detected in trace amounts close to the detection limit of the used method in the first two blood samples after initial exposure (1.5 and 3.5 h). In the 6 h blood samples, THC was not detectable anymore. THC-COOH could be detected after 1.5 h and was still found in 3 out of 8 blood samples after 14 h in concentrations between 0.5 and 1.0 ng/mL. PMID:20465865

Röhrich, J; Schimmel, I; Zörntlein, S; Becker, J; Drobnik, S; Kaufmann, T; Kuntz, V; Urban, R

2010-05-01

122

Indices of potential lead hazard.  

PubMed Central

This review is concerned with the concentrations of lead in human whole blood, erythrocytes, plasma, serum, soft tissues, bone, and urine. The extent to which redistribution of some of the bound lead occurs is outlines. The effects of lead on enzyme activities and on the accumulation of metabolic intermediates in the blood and urine are described. A brief section deals with the range of signs and symptoms that can occur and differences seen between symptomatic children and adults.

Posner, H S

1977-01-01

123

Effect of pH, Temperature, and Lead Concentration on the Bioremoval of Lead from Water Using Lemna Minor  

Microsoft Academic Search

This study examined the ability of the aquatic plant Lemna minor (duckweed) to remove soluble lead under various laboratory conditions. In a batch process L. minor was exposed to different pH values (4.5–8.0) and temperature (15–35°C) in presence of different lead concentrations (0.1–10.0 mg L) for 168 h. The amount of biomass obtained in the study period on a dry

Ya?mur Uysal; Fadime Taner

2009-01-01

124

Ingestion of lead from ammunition and lead concentrations in white-tailed sea eagles ( Haliaeetus albicilla) in Sweden  

Microsoft Academic Search

In this study we show for the first time that lead poisoning from ammunition is a significant mortality factor for white-tailed sea eagle (WSE) (Haliaeetus albicilla) in Sweden. We analyzed 118 WSEs collected between 1981 and 2004 from which both liver and kidney samples could be taken. A total of 22% of all eagles examined had elevated (>6µg\\/gd.w.) lead concentrations,

B. Helander; J. Axelsson; H. Borg; K. Holm; A. Bignert

2009-01-01

125

Natural variation in 210Po and 210Pb activity concentrations in the urine of Finnish population groups.  

PubMed

A study to determine activity concentrations of (210)Pb and (210)Po in the urine of certain Finnish population groups was conducted, to investigate the variation in natural background level of urinary excretion. The study participants were divided into three groups mainly based on their diet. The first group comprised recreational fishermen and the second group represented people consuming more reindeer meat than an average Finn, while people using drinking water with very high activity concentrations of (210)Po were selected for the third group. The fourth group was a control group. The mean urinary excretion of (210)Po in groups 1 and 2 was 73 and 100 mBq d(-1), respectively. These values were higher than the value of the control group (20 mBq d(-1)) and the mean values reported in the literature. The mean daily urinary excretion of (210)Pb in groups 1 and 2, 70 and 52 mBq d(-1), was also slightly higher than that in the control group (32 mBq d(-1)). In contrast, the excretion rates of both (210)Po and (210)Pb for the members of group 3 were one to two orders of magnitude higher than those reported in the literature. This was clearly due to the elevated levels of natural radionuclides in their drinking water. The present study demonstrates the importance of possessing good knowledge of the background levels, in order to allow the determination of the additional exposure due, for example, to the malevolent use of radiation. PMID:21922285

Muikku, Maarit; Heikkinen, Tarja; Solatie, Dina; Vesterbacka, Pia

2011-09-16

126

Relaxin concentrations in serum and urine of endangered species: correlations with physiologic events and use as a marker of pregnancy.  

PubMed

Many mammalian species are facing extinction due to problems created by human encroachment, agriculture, pollution, and willful slaughter. Among those at risk are the Asian and African elephant, Sumatran rhinoceros, and giant panda. Conservation groups try to save species in the wild by preserving habitat and limiting animal-human conflicts, often with limited success. Another alternative is to preserve the extant gene pool through captive breeding as a hedge against extinction. Measurement of circulating reproductive hormones is impractical for most wildlife species; determination of urinary or fecal hormone metabolites provides a more viable approach. To aid breeding management, one important tool is the ability to diagnose and monitor pregnancy, especially in species with long gestations (e.g., rhinos over 15 mo and elephants over 20 mo). Unfortunately, measuring progestins often is not useful diagnostically, because concentrations are similar during at least part of the pregnancy and the nonpregnant luteal phase in some species (e.g., elephants, rhinoceroses, and giant pandas). As serum relaxin reliably distinguishes between pregnancy and pseudopregnancy in bitches, relaxin measurement might also provide a method for detecting a successful pregnancy in endangered species. Appropriate immunoassay reagents have enabled the estimation of relaxin concentrations in the serum of elephants and rhinos and the determination of pregnancy establishment and the outcome. Relaxin was also detected in panda serum and urine. However, the extreme variability of the time between observed mating and parturition and the confounding factors of delayed implantation, pseudopregnancy, and frequent fetal resorptions made it impossible to use the panda relaxin data as a specific marker of pregnancy. PMID:15956734

Steinetz, Bernard G; Brown, Janine L; Roth, Terri L; Czekala, Nancy

2005-05-01

127

Evaluation of lead concentrations in 18th-century Omaha Indian skeletons using ICP-MS.  

PubMed

The analysis of skeletal remains of Omaha Indians buried between AD 1780 and 1820 indicated that lead was incorporated in cortical bone. The diagenetic or biogenetic origin of the lead was evaluated by examination of lead isotope ratios of the bones and artifacts, and comparison of lead concentrations in burial soils with those of the bones. The isotopic values of the lead artifacts demonstrate that the lead was mined in the Missouri region. Although the isotope ratios in the bones are not identical with that from the lead artifacts, there is a strong relationship between them. This finding indicates that the lead in the bone was at least partly derived from the artifacts. Because lead artifacts rarely accompanied the burials but lead was ubiquitous in the bones, we suggest a biogenetic origin for the lead. There is also the possibility that some of the lead may have been derived from pigments applied to the corpse during mortuary ritual. PMID:1443093

Reinhard, K J; Ghazi, A M

1992-10-01

128

Blood Lead Concentrations < 10 ?g/dL and Child Intelligence at 6 Years of Age  

PubMed Central

Background Few studies provide data directly relevant to the question of whether blood lead concentrations < 10 ?g/dL adversely affect children’s cognitive function. Objective We examined the association between blood lead concentrations assessed throughout early childhood and children’s IQ at 6 years of age. Methods Children were followed from 6 months to 6 years of age, with determination of blood lead concentrations at 6, 12, 18, and 24 months, and 3, 4, 5, and 6 years of age. At 6 years of age, intelligence was assessed in 194 children using the Wechsler Preschool and Primary Scale of Intelligence–Revised. We used general linear and semiparametic models to estimate and test the association between blood lead concentration and IQ. Results After adjustment for maternal IQ, HOME scale scores, and other potential confounding factors, lifetime average blood lead concentration (mean = 7.2 ?g/dL; median = 6.2 ?g/dL) was inversely associated with Full-Scale IQ (p = 0.006) and Performance IQ scores (p = 0.002). Compared with children who had lifetime average blood lead concentrations < 5 ?g/dL, children with lifetime average concentrations between 5 and 9.9 ?g/dL scored 4.9 points lower on Full-Scale IQ (91.3 vs. 86.4, p = 0.03). Nonlinear modeling of the peak blood lead concentration revealed an inverse association (p = 0.003) between peak blood lead levels and Full-Scale IQ down to 2.1 ?g/dL, the lowest observed peak blood lead concentration in our study. Conclusions Evidence from this cohort indicates that children’s intellectual functioning at 6 years of age is impaired by blood lead concentrations well below 10 ?g/dL, the Centers for Disease Control and Prevention definition of an elevated blood lead level.

Jusko, Todd A.; Henderson, Charles R.; Lanphear, Bruce P.; Cory-Slechta, Deborah A.; Parsons, Patrick J.; Canfield, Richard L.

2008-01-01

129

A longitudinal study of the relation of lead in blood to lead in air concentrations among battery workers.  

PubMed

The relation between lead in air (PbA) and lead in blood (PbB), concentrations was investigated among 44 workers in five major operations in a United States high volume, lead acid battery plant. The study covered a 30 month period in which workers received frequent PbA and PbB determinations, workers remained in a single job, and PbA concentrations averaged below the US Occupational Safety and Health Administration (OSHA) permissible exposure limit of 50 micrograms/m3. In both univariate and multivariable linear regressions, longitudinal analyses averaging PbA concentrations over the 30 month study period appeared superior to cross sectional analyses using only six month PbA averages to model PbB concentrations. The covariate adjusted coefficient (alpha value) for PbA (mu/m3) in models of PbB (micrograms/100 g) was 1.14. This figure is strikingly higher than that reported in previous studies in the lead acid battery industry in all of which PbA concentrations were substantially higher than in the current study. Plausible explanations for the difference in alpha values include non-linearity of the PbA-PbB curve, a higher fraction of large size particulate associated with higher PbA concentrations, survivor bias among workers exposed to higher PbA concentrations, and the cross sectional designs of most previous studies. Despite previously reported problems with the model used by OSHA to predict PbA-PbB relations, the findings of this study are in good agreement with the predictions of that model. PMID:1571294

Hodgkins, D G; Robins, T G; Hinkamp, D L; Schork, M A; Krebs, W H

1992-04-01

130

Increase in Lead Concentration in the Drinking Water of an Animal Care Facility  

Microsoft Academic Search

We report here the unexpected detection, and subsequent correction, of a problem that resulted in an increase in lead concentration in the drinking water of an animal research facility. At the initiation of a study, analysis of a water sample obtained from the drinking spout of an animal cage revealed a lead concentration nearly twice the Environmental Protection Agency's maximum

BRADLEY I. DAVIDOWITZ; KIRK M. BOEHM; SANDRA E. BANOVETZ; NEIL C. BINKLEY

131

The effects of different concentrations of lead salts on a variety of crop plants  

Microsoft Academic Search

An investigation is described that would be suitable for A-level or first year degree Biology or Environmental Science students. Crop plants were grown in different concentrations of lead chloride and lead nitrate. French beans, carrots and Brussels sprouts were all inhibited at concentrations over 0.01 mol dm showing stunted root growth. The difference in overall seedling length of the control

Liz Whiteley; Jamie Gibbon; Jon Hofgartner; Craig Mason; Helen Willmetts

2003-01-01

132

The Effects of Different Concentrations of Lead Salts on a Variety of Crop Plants  

ERIC Educational Resources Information Center

|An investigation is described that would be suitable for A-level or first year degree Biology or Environmental Science students. Crop plants were grown in different concentrations of lead chloride and lead nitrate. French beans, carrots and Brussels sprouts were all inhibited at concentrations over 0.01 mol dm[superscript -3] showing stunted root…

Whiteley, Liz; Gibbon, Jamie; Hofgartner, Jon; Mason, Craig; Willmetts, Helen

2003-01-01

133

Stable Isotope and Concentration Records of Atmospheric Lead Pollution in Peat and Lake Sediments in Sweden  

Microsoft Academic Search

We compare lead concentration and stable lead isotope analyses from three peat bog and three lake sediment records in Sweden. Radiocarbon dated stratigraphies give evidence that trends in the concentration of Pb in the peat and sediment cores are very similar, and follow the general outline of historical global Pb production over several thousand years. Due to the large difference

M.-L. Brännvall; R. Bindler; O. Emteryd; M. Nilsson; I. Renberg

1997-01-01

134

Copper, lead and zinc concentrations of human breast milk as affected by maternal dietary practices  

SciTech Connect

Maternal dietary practices have been found to affect the concentrations of some nutrients in human breast milk. Lead toxicity is a concern in young children. Lead, copper and zinc are thought to compete for intestinal absorption sites. The objective of the current project was to compare copper, lead and zinc contents of breast milk from practicing lacto-vegetarian and omnivore, lactating women at approximately four months post-partum. Analyses were done by atomic absorption spectrophotometry using a carbon rod attachment. Copper concentrations were higher in milk samples from lacto-ovo-vegetarians. Milk samples from the omnivores had the highest lead and zinc concentrations. Lead and copper concentrations in milk were negatively correlated. The higher zinc concentrations in the milk of the omnivore women may have been related to better utilization of zinc from meat than from plant food sources.

Umoren, J.; Kies, C.

1986-03-01

135

Copper, lead and zinc concentrations of human breast milk as affected by maternal dietary practices  

Microsoft Academic Search

Maternal dietary practices have been found to affect the concentrations of some nutrients in human breast milk. Lead toxicity is a concern in young children. Lead, copper and zinc are thought to compete for intestinal absorption sites. The objective of the current project was to compare copper, lead and zinc contents of breast milk from practicing lacto-vegetarian and omnivore, lactating

J. Umoren; C. Kies

1986-01-01

136

Abnormal function of the vasopressin-cyclic-AMP-aquaporin2 axis during urine concentrating and diluting in patients with reduced renal function. A case control study  

PubMed Central

Background The kidneys ability to concentrate and dilute urine is deteriorated during progressive renal insufficiency. We wanted to test the hypothesis that these phenomena could be attributed to an abnormal function of the principal cells in the distal part of the nephron. Methods Healthy control subjects and patients with chronic kidney diseases were studied. Group 1 comprised healthy subjects, n = 10. Groups 2-4 comprised patients with chronic kidney disease (Group 2, n = 14, e-GFR ? 90 m1/min; Group 3, n = 11, 60 m1/min ? e-GFR < 90 ml/min; and Group 4, n = 16, 15 ml/min ? e-GFR < 60 ml/min). The subjects collected urine during 24 hours. A urine concentrating test was done by thirsting during the following 12 hours. Thereafter, a urine diluting test was performed with a water load of 20 ml/kg body weight. The effect variables were urinary excretions of aquaporin2 (u-AQP2), cyclic-AMP (u-c-AMP), urine volume (UV), free water clearance (CH2O), urine osmolarity (u-Osm), and plasma arginine vasopressin (p-AVP). Results After fluid deprivation, u-Osm increased. In all groups, UV and CH2O decreased and u-AQP2 and u-c-AMP increased in Groups 1 and 2, but were unchanged in Group 3 and 4. P-AVP was significantly higher in Group 4 than in the other groups. During urine diluting, UV and CH2O reached significantly higher levels in Groups 1-3 than Group 4. Both before and after water loading, u-AQP2 and p-AVP were significantly higher and u-c-AMP was significantly lower in Group 4 than the other groups. Estimated-GFR was correlated negatively to p-AVP and positively to u-c-AMP. Conclusions Patients with moderately severe chronic kidney disease have a reduced renal concentrating and diluting capacity compared to both patients with milder chronic kidney disease and healthy control subjects. These phenomena can be attributed, at least partly, to an abnormally decreased response in the AVP-c-AMP-AQP2 axis. ClinicalTrials.Gov Identifier: NCT00313430

2010-01-01

137

AT1a receptor signaling is required for basal and water deprivation-induced urine concentration in AT1a receptor-deficient mice.  

PubMed

It is well recognized that ANG II interacts with arginine vasopressin (AVP) to regulate water reabsorption and urine concentration in the kidney. The present study used ANG II type 1a (AT(1a)) receptor-deficient (Agtr1a(-/-)) mice to test the hypothesis that AT(1a) receptor signaling is required for basal and water deprivation-induced urine concentration in the renal medulla. Eight groups of wild-type (WT) and Agtr1a(-/-) mice were treated with or without 24-h water deprivation and 1-desamino-8-d-AVP (DDAVP; 100 ng/h ip) for 2 wk or with losartan (10 mg/kg ip) during water deprivation. Under basal conditions, Agtr1a(-/-) mice had lower systolic blood pressure (P < 0.01), greater than threefold higher 24-h urine excretion (WT mice: 1.3 ± 0.1 ml vs. Agtr1a(-/-) mice: 5.9 ± 0.7 ml, P < 0.01), and markedly decreased urine osmolality (WT mice: 1,834 ± 86 mosM/kg vs. Agtr1a(-/-) mice: 843 ± 170 mosM/kg, P < 0.01), without significant changes in 24-h urinary Na(+) excretion. These responses in Agtr1a(-/-) mice were associated with lower basal plasma AVP (WT mice: 105 ± 8 pg/ml vs. Agtr1a(-/-) mice: 67 ± 6 pg/ml, P < 0.01) and decreases in total lysate and membrane aquaporin-2 (AQP2; 48.6 ± 7% of WT mice, P < 0.001) and adenylyl cyclase isoform III (55.6 ± 8% of WT mice, P < 0.01) proteins. Although 24-h water deprivation increased plasma AVP to the same levels in both strains, 24-h urine excretion was still higher, whereas urine osmolality remained lower, in Agtr1a(-/-) mice (P < 0.01). Water deprivation increased total lysate AQP2 proteins in the inner medulla but had no effect on adenylyl cyclase III, phosphorylated MAPK ERK1/2, and membrane AQP2 proteins in Agtr1a(-/-) mice. Furthermore, infusion of DDAVP for 2 wk was unable to correct the urine-concentrating defects in Agtr1a(-/-) mice. These results demonstrate that AT(1a) receptor-mediated ANG II signaling is required to maintain tonic AVP release and regulate V(2) receptor-mediated responses to water deprivation in the inner medulla. PMID:22739536

Li, Xiao C; Shao, Yuan; Zhuo, Jia L

2012-06-27

138

The relationship between body iron stores and blood and urine cadmium concentrations in US never-smoking, non-pregnant women aged 20-49 years  

SciTech Connect

Background: Cadmium is a ubiquitous environmental pollutant associated with increased risk of leading causes of mortality and morbidity in women, including breast cancer and osteoporosis. Iron deficiency increases absorption of dietary cadmium, rendering women, who tend to have lower iron stores than men, more susceptible to cadmium uptake. We used body iron, a measure that incorporates both serum ferritin and soluble transferrin receptor, as recommended by the World Health Organization, to evaluate the relationships between iron status and urine and blood cadmium. Methods: Serum ferritin, soluble transferrin receptor, urine and blood cadmium values in never-smoking, non-pregnant, non-lactating, non-menopausal women aged 20-49 years (n=599) were obtained from the 2003-2008 National Health and Nutrition Examination Surveys. Body iron was calculated from serum ferritin and soluble transferrin receptor, and iron deficiency defined as body iron <0 mg/kg. Robust linear regression was used to evaluate the relationships between body iron and blood and urine cadmium, adjusted for age, race, poverty, body mass index, and parity. Results: Per incremental (mg/kg) increase in body iron, urine cadmium decreased by 0.003 {mu}g/g creatinine and blood cadmium decreased by 0.014 {mu}g/L. Iron deficiency was associated with 0.044 {mu}g/g creatinine greater urine cadmium (95% CI=0.020, 0.069) and 0.162 {mu}g/L greater blood cadmium (95% CI=0.132, 0.193). Conclusions: Iron deficiency is a risk factor for increased blood and urine cadmium among never-smoking, pre-menopausal, non-pregnant US women, independent of age, race, poverty, body mass index and parity. Expanding programs to detect and correct iron deficiency among non-pregnant women merits consideration as a potential means to reduce the risk of cadmium associated diseases. - Highlights: {yields} Body iron was calculated from serum ferritin and soluble transferrin receptor. {yields} Body iron was inversely associated with blood and urine cadmium in US women. {yields} Inverse associations with blood cadmium were evident in all race/ethnic subsamples. {yields} Inverse associations with urine cadmium were evident in women of other/multi-race. {yields} Black women had lower mean body iron compared to white women.

Gallagher, Carolyn M., E-mail: 2crgallagher@optonline.net [PhD Program in Population Health and Clinical Outcomes Research, Stony Brook University, NY (United States) and Department of Preventive Medicine, Stony Brook University, Z-8036, Level 3, HSC, Stony Brook, NY 11794-8036 (United States); Chen, John J.; Kovach, John S. [Department of Preventive Medicine, Stony Brook University, Z-8036, Level 3, HSC, Stony Brook, NY 11794-8036 (United States)] [Department of Preventive Medicine, Stony Brook University, Z-8036, Level 3, HSC, Stony Brook, NY 11794-8036 (United States)

2011-07-15

139

Tissue lead concentrations and shot ingestion in nine species of waterbirds from the Camargue (France).  

PubMed

This study investigates the relationship among lead exposure (shot ingestion), current lead impregnation (liver lead values), current and previous lead impregnation (bone lead values), and lead excretion (feather lead) in nine species of waterbird from the Camargue (Rhone river delta), France. Results indicate that for individuals there is no readily predictable relationship between ingested shot and liver or bone lead concentrations. However, at the "population" level, and interspecifically, significant positive relationships exist between the susceptibility to shot ingestion and the degree of lead impregnation. Shoveler (Anas clypeata) proved to be an exception, with a high level of shot ingestion and no elevated tissue lead values. This is probably related to dietary factors. Species with a high degree of current lead contamination tended to be those that had also previously absorbed elevated levels of lead. Feather lead concentrations were not clearly related to the vulnerability of a species to shot ingestion or lead poisoning. There was no significant absorption of arsenic and antimony from gunshot associated with lead absorption. PMID:1280587

Pain, D J; Amiard-Triquet, C; Sylvestre, C

1992-10-01

140

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

PubMed

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 those found in the present study may imply an increased risk for adverse health effects. Children and women of child-bearing age are of special concern due to the neurodevelopmental effects of lead. PMID:22651819

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

2012-04-24

141

Lead concentrations and isotopic signatures in vintages of French wine between 1950 and 1991  

SciTech Connect

Vintages of French wine from 1950 to 1991 were analyzed for lead isotopes and concentration to investigate whether they might be used to archive the isotopic composition of the anthropogenic lead in aerosols to which the vineyard was exposed. Early vintages (1950--1980) contained 78--227 ng/g of lead with {sup 206}Pb/{sup 207}Pb ratios between 1.152 and 1.173, while the later vintages displayed significantly lower concentrations and a smaller range of isotopic ratios. The concentration of trimethyl lead, which is associated with automobile emissions, was found to be poorly correlated with total lead in the wines, suggesting that automobile aerosols were not a significant source of the lead. This result was supported by lead isotope data which showed a poor correlation with the available petrol and aerosol data. To identify its origin lead isotopes were measured in vineyard aerosols, soil particles, bottle caps, corks, and brass components used to dispense the wine. Although a dominant source could not be identified there was some evidence to suggest that brass which had a high lead concentration was a significant contributor. Because the lead contribution from the processing of wine was probably relatively high in the past it is unlikely that old vintages of wine will be a suitable archive for lead isotopes in aerosols.

Rosman, K.J.R.; Chisholm, W.; Jimi, S. [Curtin Univ. of Technology, Perth, Western Australia (Australia); Candelone, J.P. [Curtin Univ. of Technology, Perth, Western Australia (Australia)]|[Domaine Univ., Saint Martin d`Heres (France). Lab. de Glaciologie et Geophysique de l`Environnement; Boutron, C.F. [Domaine Univ., Saint Martin d`Heres (France). Lab. de Glaciologie et Geophysique de l`Environnement]|[Univ. Joseph Fourier de Grenoble (France); Teissedre, P.L. [Univ. Montpellier (France). Centre de Formation et de Recherche; Adams, F.C. [Univ. of Antwerp, Wilrijk (Belgium). Dept. of Chemistry

1998-08-01

142

Blood lead concentration, renal function, and blood pressure in London civil servants.  

PubMed Central

Blood lead concentration was measured in 398 male and 133 female London civil servants not subject to industrial exposure to heavy metals. The relation between blood lead and serum creatinine concentrations and blood pressure were examined. Blood lead concentration ranged from 0.20 to 1.70 mumol/l with a geometric mean concentrations of 0.58 mumol/l in men and 0.46 mumol/l in women (p less than 0.001). In women blood lead concentration increased with age (r = +0.27; p = 0.002). In the two sexes blood lead concentration was positively correlated with the number of cigarettes smoked a day (men r = +0.17 and women r = +0.22; p less than or equal to 0.01), with the reported number of alcoholic beverages consumed a day (men r = +0.34 and women r = 0.23; p less than 0.01), and with serum gamma-glutamyltranspeptidase (men r = +0.23 and women r = +0.14; for men p less than 0.01). Blood lead concentration was not correlated with body weight, body mass index, and employment grade. In men 14% of the variance of blood lead concentration was explained by the significant and independent contributions of smoking and alcohol intake and in women 16% by age, smoking, and alcohol consumption. In men serum creatinine concentration tended to rise by 0.6 mumol/l (95% confidence interval from -0.2 to +1.36 mumol/l) for each 25% increment in blood lead concentration. In men and women the correlations between blood lead concentration and systolic and diastolic blood did not approach statistical significance. In conclusion, in subjects not exposed to heavy metals at work gender, age, smoking, and alcohol intake are determinants of blood lead concentration. At a low level of exposure, lead accumulation may slightly impair renal function, whereas blood pressure does not seem to be importantly influenced. Alternatively, a slight impairment of renal function may give rise to an increase in blood lead concentration.

Staessen, J; Yeoman, W B; Fletcher, A E; Markowe, H L; Marmot, M G; Rose, G; Semmence, A; Shipley, M J; Bulpitt, C J

1990-01-01

143

Concentrations of lead in maternal blood, cord blood, and breast milk.  

PubMed Central

Lead concentrations in maternal blood, umbilical cord blood, and breast milk from 114 women who were not occupationally exposed to lead were determined by graphite atomic absorption spectrophotometry. The mean concentrations of lead in maternal blood, umbilical cord blood and breast milk were 0.7, 0.55, and 0.23 mumol/l, respectively. A significant correlation was observed between maternal and umbilical cord blood (r = 0.63). A lower correlation was noted between maternal blood and breast milk (r = 0.29). These results suggest that lead freely crosses the placental barrier from mother to fetus and the transfer of this heavy metal from maternal tissues to breast milk is possible, but the metabolic mechanisms are more complicated. In addition, a longitudinal study was conducted of concentrations of lead in breast milk in nine lactating women. Results suggested no significant change in the content of lead in breast milk during early lactation.

Ong, C N; Phoon, W O; Law, H Y; Tye, C Y; Lim, H H

1985-01-01

144

Vitamin D receptor Fok1 polymorphism and blood lead concentration in children.  

PubMed Central

Variation in blood lead concentration is caused by a complex interaction of environmental, social, nutritional, and genetic factors. We evaluated the association between blood lead concentration and a vitamin D receptor (VDR) gene polymorphism. Environmental samples and blood were analyzed for lead, nutritional and behavioral factors were assessed, and VDR -Fok1 genotype was determined in 245 children. We found a significant interaction between floor dust lead and genotype on blood lead concentration. For every 1 microg/ft(2) increase in floor dust, children with VDR -FF genotype had a 1.1% increase in blood lead [95% confidence interval (CI), 0.69-1.5], VDR -Ff, 0.53% increase (95% CI, 0.1-0.92), and VDR -ff, 3.8% increase (95% CI, 1.2-6.3); however, at floor dust levels < 10 microg/ft(2), children with VDR -ff had the lowest blood lead concentrations. These data suggest that VDR -Fok1 is an effect modifier of the relationship of floor dust lead exposure and blood lead concentration.

Haynes, Erin N; Kalkwarf, Heidi J; Hornung, Richard; Wenstrup, Richard; Dietrich, Kim; Lanphear, Bruce P

2003-01-01

145

Elevated soil lead concentrations in residential yards in Appleton, WI, a small Midwestern city  

NASA Astrophysics Data System (ADS)

Elevated soil lead concentrations are well documented in large urban areas, having been attributed to a combination of leaded-paint, leaded-gasoline, and industrial emissions. Fewer studies, however, have been conducted in smaller communities. We analyzed 200 surface soils in the neighborhood near Lawrence University’s campus in Appleton, WI (population ~70,000). Like many larger cities Appleton has a historic city-center. However, it is has no high-density housing or commercial districts and has not seen heavy traffic. The socioeconomic pressures that lead to disrepair of inner city neighborhoods have been less prevalent here as well. At each property 3 integrated samples were taken, one adjacent to the front of the house, one in the front lawn, and one between the road and sidewalk. We correlated building and property traits (e.g. structure age, distance from road, exterior type, exterior condition, direction of exposure, and assessed home value) with soil lead concentrations determined by XRF and subsequently, mapped these data for geospatial patterns. Soil lead concentrations in the city park and campus greens were typically less than 100 ppm. The highest lead concentrations are close to campus, which has a number of civil war era buildings and homes. High lead concentrations (averaging over 1,000 ppm near the home, with concentrations as high as 10,000 ppm) were associated with aging, poorly maintained structures as expected. However, a number of well-maintained structures also show substantially elevated concentrations. These soil lead concentrations are not dissimilar to those found in much larger cities such as New Orleans, Milwaukee, and Chicago. Lead levels dropped quickly as distance from the house increased suggesting that the contamination is from lead paint and not from gasoline exhaust. Furthermore, samples taken adjacent to the main arterial through town exhibited relatively low, but slightly elevated lead levels (~250 ppm). Not surprisingly, these concentrations are in line with those typically found in suburban settings, rather than urban settings. Studying the nature and distribution of soil lead contamination in a smaller city such as Appleton will allow for a better understanding of the public health risks in this and similar cities. Additionally, with fewer likely contributors to soil lead contamination, this study allows a clearer connection to be drawn between one primary factor, paint, and the distribution of soil lead.

Clark, J. J.; Knudsen, A. C.

2010-12-01

146

Blood pressure and hair cadmium, lead, copper, and zinc concentrations in Mississippi adolescents  

SciTech Connect

Increased cadmium and lead tissue concentrations have been associated with deaths resulting from heart disease. Liver cadmium concentrations and aortic lead levels have been reported to be higher in deaths resulting from heart related disease compared to non-heart related disease. Essential trace elements such as copper and zinc have also been postulated as playing a role in coronary heart disease. The objective of this study was to evaluate the concentrations of hair lead, cadmium, copper, and zinc in Mississippi adolescents and to determine if these hair elements were associated with blood pressure.

Medeiros, D.M.; Pellum, L.K.

1985-02-01

147

Deficits in cognitive function and achievement in Mexican first-graders with low blood lead concentrations.  

PubMed

Elevated blood lead levels in children are associated with lower scores on tests of cognitive functioning. Recent studies have reported inverse relations between lifetime exposure and intellectual functioning at blood lead concentrations below 10 microg/dL, the Centers for Disease Control and Prevention's (CDC) level of concern. We report associations between blood lead and cognitive performance for first-grade Mexican children living near a metal foundry. Using a cross-sectional design, we examined the relation between children's concurrent blood lead concentrations (mean (SD) 11.4 microg/dL (6.1)) and their performance on 14 tests of global or specific cognitive functions. The blood lead-cognition relations were modeled using both linear and nonlinear methods. After adjustment for covariates, a higher blood lead level was associated with poorer cognitive performance on several cognitive tests. Segmented linear regressions revealed significant effects of lead but only for the segments defined by a concurrent blood lead concentration below 10-14 microg/dL. One implication of these findings is that at the age of 7 years, even in the absence of information on lead exposure in infancy and early childhood, a test result with blood lead < 10 microg/dL should not be considered safe. Together with other recent findings, these results add to the empirical base of support available for evaluating the adequacy of current screening guidelines and for motivating efforts at primary prevention of childhood lead exposure. PMID:16169549

Kordas, Katarzyna; Canfield, Richard L; López, Patricia; Rosado, Jorge L; Vargas, Gonzalo García; Cebrián, Mariano E; Rico, Javier Alatorre; Ronquillo, Dolores; Stoltzfus, Rebecca J

2005-09-19

148

Association of Prenatal and Childhood Blood Lead Concentrations with Criminal Arrests in Early Adulthood  

PubMed Central

Background Childhood lead exposure is a purported risk factor for antisocial behavior, but prior studies either relied on indirect measures of exposure or did not follow participants into adulthood to examine the relationship between lead exposure and criminal activity in young adults. The objective of this study was to determine if prenatal and childhood blood lead concentrations are associated with arrests for criminal offenses. Methods and Findings Pregnant women were recruited from four prenatal clinics in Cincinnati, Ohio if they resided in areas of the city with a high concentration of older, lead-contaminated housing. We studied 250 individuals, 19 to 24 y of age, out of 376 children who were recruited at birth between 1979 and 1984. Prenatal maternal blood lead concentrations were measured during the first or early second trimester of pregnancy. Childhood blood lead concentrations were measured on a quarterly and biannual basis through 6.5 y. Study participants were examined at an inner-city pediatric clinic and the Cincinnati Children's Hospital Medical Center in Cincinnati, Ohio. Total arrests and arrests for offenses involving violence were collected from official Hamilton County, Ohio criminal justice records. Main outcomes were the covariate-adjusted rate ratios (RR) for total arrests and arrests for violent crimes associated with each 5 ?g/dl (0.24 ?mol/l) increase in blood lead concentration. Adjusted total arrest rates were greater for each 5 ?g/dl (0.24 ?mol/l) increase in blood lead concentration: RR = 1.40 (95% confidence interval [CI] 1.07–1.85) for prenatal blood lead, 1.07 (95% CI 0.88–1.29) for average childhood blood lead, and 1.27 (95% CI 1.03–1.57) for 6-year blood lead. Adjusted arrest rates for violent crimes were also greater for each 5 ?g/dl increase in blood lead: RR = 1.34 (95% CI 0.88–2.03) for prenatal blood lead, 1.30 (95% CI 1.03–1.64) for average childhood blood lead, and 1.48 (95% CI 1.15–1.89) for 6-year blood lead. Conclusions Prenatal and postnatal blood lead concentrations are associated with higher rates of total arrests and/or arrests for offenses involving violence. This is the first prospective study to demonstrate an association between developmental exposure to lead and adult criminal behavior.

Wright, John Paul; Dietrich, Kim N; Ris, M. Douglas; Hornung, Richard W; Wessel, Stephanie D; Lanphear, Bruce P; Ho, Mona; Rae, Mary N

2008-01-01

149

Impact of Low Blood Lead Concentrations on IQ and School Performance in Chinese Children  

PubMed Central

Objectives Examine the relationships between blood lead concentrations and children's intelligence quotient (IQ) and school performance. Participants and Methods Participants were 1341 children (738 boys and 603 girls) from Jintan, China. Blood lead concentrations were measured when children were 3–5 years old. IQ was assessed using the Chinese version and norms of the Wechsler Preschool and Primary Scale of Intelligence – Revised when children were 6 years old. School performance was assessed by standardized city tests on 3 major subjects (Chinese, Math, and English [as a foreign language]) when children were age 8–10 years. Results Mean blood lead concentration was 6.43 µg/dL (SD?=?2.64). For blood lead concentrations, 7.8% of children (n?=?105) had ?10.0 µg/dL, 13.8% (n?=?185) had 8.0 to <10.0 µg/dL, and 78.4% (n?=?1051) had <8.0 µg/dL. Compared to children with blood lead concentrations <8 µg/dL, those with blood lead concentrations ?8 µg/dL scored 2–3 points lower in IQ and 5–6 points lower in school tests. There were no significant differences in IQ or school tests between children with blood lead concentrations groups 8–10 and ?10 µg/dL. After adjustment for child and family characteristics and IQ, blood lead concentrations ?10 µg/dL vs <8 µg/dL at ages 3–5 years was associated with reduced scores on school tests at age 8–10 years (Chinese, ??=??3.54, 95%CI?=??6.46, ?0.63; Math, ??=??4.63, 95%CI?=??7.86, ?1.40; English, ??=??4.66, 95%CI?=??8.09, ?1.23). IQ partially mediated the relationship between elevated blood lead concentrations and later school performance. Conclusions Findings support that blood lead concentrations in early childhood, even <10 µg/dL, have a long-term negative impact on cognitive development. The association between blood lead concentrations 8–10 µg/dL and cognitive development needs further study in Chinese children and children from other developing countries.

Liu, Jianghong; Li, Linda; Wang, Yingjie; Yan, Chonghuai; Liu, Xianchen

2013-01-01

150

Liver Lead Concentrations in Raptors in New Jersey, USA, 2008—2010  

Microsoft Academic Search

Lead exposure in New Jersey raptors was assessed by analyzing liver samples from carcasses obtained from wildlife rehabilitators.\\u000a Samples were collected from 221 individuals representing 13 species. Concentrations were within the range of normal background\\u000a exposure in 12 species. One red-tailed hawk had a liver lead concentration consistent with clinical poisoning (7.4 ?g\\/g wet\\u000a weight), which represents an incidence of 1%

William StansleyLisa; Lisa A. Murphy

2011-01-01

151

Deficits in cognitive function and achievement in Mexican first-graders with low blood lead concentrations  

Microsoft Academic Search

Elevated blood lead levels in children are associated with lower scores on tests of cognitive functioning. Recent studies have reported inverse relations between lifetime exposure and intellectual functioning at blood lead concentrations below 10?g\\/dL, the Centers for Disease Control and Prevention's (CDC) level of concern. We report associations between blood lead and cognitive performance for first-grade Mexican children living near

Katarzyna Kordas; Richard L. Canfield; Patricia López; Jorge L. Rosado; Gonzalo García Vargas; Mariano E. Cebrián; Javier Alatorre Rico; Dolores Ronquillo; Rebecca J. Stoltzfus

2006-01-01

152

Urination - painful  

MedlinePLUS

... such as yeast or other infections of the vulva and vagina Other causes of painful urination include: ... in the urine ? Are there any rashes or itching in the genital area? What medications are you ...

153

Sodium - urine  

MedlinePLUS

The sodium urine test measures the amount of salt (sodium) in a urine sample. Sodium can also ... L/day), depending on how much fluid and salt you consume. The examples above are common measurements ...

154

Ethyl glucuronide concentrations in oral fluid, blood, and urine after volunteers drank 0.5 and 1.0 g/kg doses of ethanol.  

PubMed

The aim of this study was to investigate the concentrations of ethyl glucuronide (EtG) in oral fluid, blood, and urine after healthy volunteers drank two doses of ethanol, 0.5 (n = 11) and 1.0 g/kg (n = 10), after an overnight fast. Samples of oral fluid, blood, and urine were collected before drinking started and at 1.5, 3.5, 5.5, 8.5, 11.5, and 24 h post-dosing. Following ingestion of low dose of ethanol, the Cmax for EtG was 0.36 mg/L (range 0.28-0.41 mg/L) in blood and 69.8 mg/L (range 47.1-96.5 mg/L) in urine. In oral fluid, the concentrations were < 1% of those in blood, and only three subjects exceeded the limit of quantification for EtG in oral fluid. After ingestion of the high dose of ethanol, the Cmax for EtG was 1.06 mg/L (range 0.8-1.22 mg/L) in blood, 159.9 mg/L (range 97.2-225.5 mg/L) in urine, and 0.032 mg/L (range 0.013-0.059 mg/L) in oral fluid. The median oral fluid/blood ratio was 0.029 (range 0.012-0.054) for EtG. The detection time for EtG was median 11.5 h (range 3.5-11.5 h) in oral fluid. According to this, the detection time for EtG in oral fluid is therefore only a few hours longer than for ethanol itself and represents limited additional value. PMID:20663284

Høiseth, Gudrun; Yttredal, Borghild; Karinen, Ritva; Gjerde, Hallvard; Mørland, Jørg; Christophersen, Asbjørg

155

Concentrations of N-methyl-2-pyrrolidone (NMP) and its metabolites in plasma and urine following oral administration of NMP to rats.  

PubMed

The primary aims were to study the metabolism in rats and to determine the biological levels after one oral developmentally toxic dose of N-methyl-2-pyrrolidone (NMP), a widely used industrial chemical. Non-pregnant female Sprague-Dawley rats were given an oral single dose of either a non-toxic dose of 125 mg NMP/kg (group 1) by gavage or a developmentally toxic dose of 500 mg/kg (group 2). Blood plasma (7 rats per time point) and urine (10 rats per time point) were sampled up to 72 h after administration and analyzed using mass spectrometry. In both plasma and urine NMP, 5-hydroxy-N-methyl-2-pyrrolidone (5-HNMP), N-methylsuccinimide and 2-hydroxy-N-methylsuccinimide (2-HMSI) and 2-pyrrolidone (2-P) were identified. In urine 48% of the administered dose was recovered as 5-HNMP and 2-5% as 2-HMSI. The total recovery in urine was 53-59%. The peak concentrations for NMP in plasma were 1.2 and 6.9 mmol/l, 0.42 and 0.76 mmol/l for 5-HNMP, 0.07 and 0.31 mmol/l for MSI and for 2-HMSI the concentrations were 0.02 and 0.05 mmol/l for groups 1 and 2, respectively. In summary, the same metabolites were found in rats as in humans and the biological levels were reported for NMP and its metabolites after oral exposure to a developmentally toxic dose and one non-toxic dose of NMP. PMID:15951091

Carnerup, Martin A; Saillenfait, Anne Marie; Jönsson, Bo A G

2005-09-01

156

Elevated Blood Lead Concentrations and Vitamin D Deficiency in Winter and Summer in Young Urban Children  

PubMed Central

Background It is widely recognized that blood lead concentrations are higher in the summer than in winter. Although the effects of some environmental factors such as lead in dust on this phenomenon have been studied, relationships to sunlight-induced vitamin D synthesis have not been adequately investigated. Vitamin D status is influenced by the diet, sunlight exposure, age, skin pigmentation, and other factors, and may modify gastrointestinal lead absorption or release of lead stored in bones into the bloodstream. Objective and Methods We collected paired blood samples from 142 young, urban African-American and Hispanic children in the winter and summer to study the seasonal increase in blood lead and its relationships to vitamin D nutrition, age, and race. Results A winter/summer (W/S) increase in blood lead concentrations of 32.4% was found for children 1–3 years of age. There was a smaller W/S increase of 13.0% in children 4–8 years of age. None of the 51 Hispanic children had an elevated blood lead concentration (? 10 ?g/dL) during the winter, and only one had an elevated summertime concentration. In contrast, elevated blood lead concentrations were frequent in the 91 African-American children, especially those 1–3 years of age. For the latter, the percentage with elevated blood lead levels increased from 12.2% in winter to 22.5% in summer. A 1.2% W/S increase in serum 25-hydroxy-vitamin D (serum 25-OH-D) concentrations was found for children 1–3 years of age. However, in children 4–8 years of age the W/S increase in serum 25-OH-D was much larger—33.6%. The percentages of children with low (< 16 ?g/L) serum 25-OH-D concentrations were 12.0% in winter and 0.7% in summer and were consistently greater in African-American than in Hispanic children. The seasonal increases in blood lead and serum 25-OH-D in children 4–8 years of age were significantly associated. Conclusion The higher summertime serum 25-OH-D concentrations for the 4- to 8-year-old children are likely caused by increased sunlight-induced vitamin D synthesis and may contribute to the seasonal increase in blood lead. Age and race are key factors that affect blood lead and vitamin D nutrition, as well as their interactions, in young urban children.

Kemp, Francis W.; Neti, Prasad V.S.V.; Howell, Roger W.; Wenger, Peter; Louria, Donald B.; Bogden, John D.

2007-01-01

157

Blood lead concentrations in marine mammals validate estimates of 10{sup 2}- to 10{sup 3}-fold increase in human blood lead concentrations  

SciTech Connect

Measurements of ultra-low ambient blood lead (PbB) concentrations (mean {+-} SD = 0.13 {+-} 0.06 {micro}g/dL) in Northern elephant seals (Mirounga angustirostris) validate previous estimates of ultra-low PbB levels in preindustrial humans. These estimates had been unsubstituted, since PbB levels in this range had never been measured in any organisms prior to this study. Similarities in PbB levels among these contemporary and preindustrial mammals are consistent with similarities in their measured and estimated lead exposures, respectively. The marginally higher PbB levels and rates of lead exposure in contemporary marine mammals are, also, consistent with lead isotopic composition analyses that indicate their PbB levels have been elevated from exposure to industrial lead. Consequently, these analyses substantiate concerns that current baseline PbB levels in humans, which are estimated to be two to three orders of magnitude above natural levels, may still constitute public health risks.

Owen, B.D.; Flegal, A.R. [Univ. of California, Santa Cruz, CA (United States)

1998-08-01

158

Lead concentrations in the northeast Pacific: evidence for global anthropogenic perturbations  

NASA Astrophysics Data System (ADS)

Lead concentrations were determined by isotope dilution mass spectrometry in 34 surface- and deep-water samples collected in the northeast Pacific between Hawaii and California and off the California coast using a deep-water sampler protected against fouling by contamination from the ship and hydrowire. Measured concentrations lie more than one order of magnitude below previously published open ocean values and they show that in most cases 90% or more of the total lead is in a dissolved form. Lead concentrations are about 10-fold higher in surface and thermocline waters than in deep waters; values drop as low as 1 ng/kg (5 pmol/kg) below 3500 m depth. Lead profiles thus appear different compared to those of most trace metals, which show enrichment in deep waters compared to surface concentrations. Lead concentrations in surface waters increase from 5 to 15 ng/kg (25 to 75 pmol/kg) along a transect starting from a location 200 km off the California coast and continuing towards the center of the North Pacific Gyre. This increase is congruent with that observed for 210Pb concentrations in the same waters sampled at the same time. Lead is supplied to the open North Pacific largely from the atmosphere, at a rate of about 60 ng/cm2 yr, which exceeds the prehistoric oceanic output flux of authigenic lead recorded in pelagic sediments about tenfold. This excess originates from emissions from smelters and combustion of leaded gasoline, overwhelming natural lead inputs that entered the ocean during prehistoric time probably largely through rivers. Vertical lead concentration profiles below the surface mixed layer are probably not in steady state. There, concentrations must be increasing in response to the increase of anthropogenic inputs because the estimated lead residence times are more than 20 years in the thermocline and about 80 years in deep waters. Based on an estimated 10-fold input and concentration increase since the mid-eighteenth century in the surface mixed layer in the central northeast Pacific, it is calculated that the 10 ng/kg average concentration between 100 and 900 m is 2 to 5 times larger, and the 1.8 ng/kg average concentration between 900 and 5000 m depth is about 2 times larger than it was in the mid-eighteenth century. Profiles of lead concentrations in the North Atlantic are expected to be shifted generally to larger values by a factor of 2 to 3 compared to those in the North Pacific because of the effects of greater industrial lead contamination, while lead concentration profiles in the South Pacific are expected to be shifted generally to lower values compared to the North Pacific by about this same factor because of the effects of lesser industrial lead contamination.

Schaule, Bernhard K.; Patterson, Clair C.

1981-06-01

159

Influence of multiple injections of human chorionic gonadotropin (hCG) on urine and serum endogenous steroids concentrations  

Microsoft Academic Search

Since it is established that human chorionic gonadotropin (hCG) affects testosterone production and release in the human body, the use of this hormone as a performance enhancing drug has been prohibited by the World Anti-Doping Agency. Nowadays, the only validated biomarker of a hCG doping is its direct quantification in urine. However, this specific parameter is subjected to large inter-individual

Emmanuel Strahm; Pedro Marques-Vidal; François Pralong; Jiri Dvorak; Martial Saugy; Norbert Baume

2011-01-01

160

Association of blood lead concentrations with mortality in older women: a prospective cohort study  

PubMed Central

Background Blood lead concentrations have been associated with increased risk of cardiovascular, cancer, and all-cause mortality in adults in general population and occupational cohorts. We aimed to determine the association between blood lead, all cause and cause specific mortality in elderly, community residing women. Methods Prospective cohort study of 533 women aged 65–87 years enrolled in the Study of Osteoporotic Fractures at 2 US research centers (Baltimore, MD; Monongahela Valley, PA) from 1986–1988. Blood lead concentrations were determined by atomic absorption spectrometry. Using blood lead concentration categorized as < 8 ?g/dL (0.384 ?mol/L), and ? 8 ?g/dL (0.384 ?mol/L), we determined the relative risk of mortality from all cause, and cause-specific mortality, through Cox proportional hazards regression analysis. Results Mean blood lead concentration was 5.3 ± 2.3 ?g/dL (range 1–21) [0.25 ± 0.11 ?mol/L (range 0.05–1.008)]. After 12.0 ± 3 years of > 95% complete follow-up, 123 (23%) women who died had slightly higher mean (± SD) blood lead 5.56 (± 3) ?g/dL [0.27(± 0.14) ?mol/L] than survivors: 5.17(± 2.0) [0.25(± 0.1) ?mol/L] (p = 0.09). Women with blood lead concentrations ? 8 ?g/dL (0.384 ?mol/L), had 59% increased risk of multivariate adjusted all cause mortality (Hazard Ratio [HR], 1.59; 95% confidence interval [CI], 1.02–2.49) (p = 0.041) especially coronary heart disease (CHD) mortality (HR = 3.08 [CI], (1.23–7.70)(p = 0.016), compared to women with blood lead concentrations < 8 ?g/dL(< 0.384 ?mol/L). There was no association of blood lead with stroke, cancer, or non cardiovascular deaths. Conclusion Women with blood lead concentrations of ? 8 ?g/dL (0.384 ?mol/L), experienced increased mortality, in particular from CHD as compared to those with lower blood lead concentrations.

2009-01-01

161

The Soluble Receptor for Vitamin B12 Uptake (sCD320) Increases during Pregnancy and Occurs in Higher Concentration in Urine than in Serum  

PubMed Central

Background Cellular uptake of vitamin B12 (B12) demands binding of the vitamin to transcobalamin (TC) and recognition of TC-B12 (holoTC) by the receptor CD320, a receptor expressed in high quantities on human placenta. We have identified a soluble form of CD320 (sCD320) in serum and here we present data on the occurrence of this soluble receptor in both serum and urine during pregnancy. Methods We examined serum from twenty-seven pregnant women (cohort 1) at gestational weeks 13, 24 and 36 and serum and urine samples from forty pregnant women (cohort 2) tested up to 8 times during gestational weeks 17-41. sCD320, holoTC, total TC and complex formation between holoTC and sCD320 were measured by in-house ELISA methods, while creatinine was measured on the automatic platform Cobas 6000. Size exclusion chromatography was performed on a Superdex 200 column. Results Median (range) of serum sCD320 increased from 125 (87-839) pmol/L (week 15) to reach a peak value of 199 (72-672) pmol/L (week 35) then dropped back to its baseline level just before birth (week 40). Around one third of sCD320 was precipitated with holoTC at all-time points studied. The urinary concentration of sCD320 was around two fold higher than in serum. Urinary sCD320/creatinine ratio correlated with serum sCD320 and reached a peak median level of 53 (30–101) pmol/mmol creatinine (week 35). sCD320 present in serum and urine showed the same elution pattern upon size exclusion chromatography. Conclusion We report for the first time that sCD320 is present in urine and in a higher concentration than in serum and that serum and urine sCD320 increase during pregnancy. The high urinary concentration and the strong correlation between urinary and serum sCD320 suggests that sCD320 is filtered in the kidney.

Abuyaman, Omar; Andreasen, Birgitte H.; Kronborg, Camilla; Vittinghus, Erik; Nexo, Ebba

2013-01-01

162

Ruminal metabolism of flaxseed ( Linum usitatissimum) lignans to the mammalian lignan enterolactone and its concentration in ruminal fluid, plasma, urine and milk of dairy cows.  

PubMed

Secoisolariciresinol diglucoside is the main flax (Linum usitatissimum) lignan that is converted to the mammalian lignans enterodiol (ED) and enterolactone (EL) by gastrointestinal microbiota. The objectives of the present study were to investigate the role of ruminal microbiota and the effects of flax oil on in vivo metabolism of flax lignans and concentration of EL in biological fluids. Four rumen-cannulated dairy cows were used in a 4 x 4 Latin square design. There were four periods of 21 d each and four treatments utilising flax hulls (1800 g/d) and oil (400 g/d) supplements. The treatments were: (1) oil and hulls administered in the rumen and abomasal infusion of water; (2) oil and hulls administered in the abomasum; (3) oil infused in the abomasum and hulls placed in the rumen; (4) oil placed in the rumen and hulls administered in the abomasum. Samples were collected during the last week of each period and subjected to chemical analysis. The site of supplementation of oil and hulls had no effect on ruminal EL concentration. Supplementing flax oil in the rumen and the abomasum led to similar EL concentrations in urine, plasma and milk. Concentrations of EL were higher in the urine, plasma and milk of cows supplemented with hulls in the rumen than in those placed with hulls in the abomasum. The present study demonstrated that ruminal microbiota play an important role in the metabolism of flax lignans. PMID:19393113

Gagnon, Nathalie; Côrtes, Cristiano; da Silva, Daniele; Kazama, Ricardo; Benchaar, Chaouki; dos Santos, Geraldo; Zeoula, Lucia; Petit, Hélène V

2009-04-27

163

Relation between urinary beta-aminoisobutyric acid excretion and concentration of lead in the blood of workers occupationally exposed to lead.  

PubMed Central

Urinary beta-aminoisobutyric acid (ABA) concentration was determined by fluorometric high performance liquid chromatography in 22 workers occupationally exposed to lead. The urinary excretion of ABA was increased with increasing exposure to lead. The excretion of urinary ABA had a significant correlation with concentration of lead in blood (Pb-B) (r = 0.581), similar to the correlation of Pb-B with urinary delta-aminolaevulinic acid (ALA) concentration (r = 0.563). The determination of urinary ABA concentration in workers exposed to lead, therefore, may offer a new approach for evaluating the health effect of lead.

Tomokuni, K; Ichiba, M; Mori, K

1992-01-01

164

Predictive value of determinations of zinc protoporphyrin for increased blood lead concentrations.  

PubMed

Blood lead (PbB) and red cell zinc protoporphyrin (ZPP) concentrations are widely used biomarkers for lead toxicity. It is uncertain, however, whether either or both are needed for monitoring lead exposure and how discordant PbB and ZPP values should be interpreted. We reviewed the results of PbB and ZPP determinations in 94 workers in a lead-battery plant over a 13-year period and retrieved all 807 sets of tests in which both PbB and ZPP were available, with a follow-up PbB value 6 months later. PbB exceeded 1.93 micromol/L (40 microg/dL) in 414 (51%), and 2.90 micromol/L (60 microg/dL) in 105 (14%) of the blood samples. We derived the test properties of various ZPP concentrations for concurrent "toxic" PbB concentrations, defined as > or = 1.93 and 2.90 micromol/L (40 and 60 microg/dL). The results indicated that, given a population of lead-exposed workers with a 10% prevalence of PbB of > or = 2.90 micromol/L (60 microg/dL), a policy of testing PbB only in those with ZPP > 0.71 micromol/L (40 microg/dL) would obviate 42% of the PbB tests, but would miss about three cases with toxic PbB concentrations in every 200 workers at risk. A finding of increased ZPP concentrations with a concurrent "nontoxic" PbB was associated with an increased risk of a toxic PbB concentration 6 months later. We conclude that (a) screening by testing only ZPP does not safeguard exposed persons against lead toxicity, and (b) the frequency of PbB monitoring should be guided by estimates of the risk of future lead toxicity in individual workers. PMID:9625054

Froom, P; Kristal-Boneh, E; Benbassat, J; Ashkanazi, R; Ribak, J

1998-06-01

165

Molecular cloning and characterization of a novel carboxylesterase-like protein that is physiologically present at high concentrations in the urine of domestic cats (Felis catus).  

PubMed

Normal mammals generally excrete only small amounts of protein in the urine, thus avoiding major leakage of proteins from the body. Proteinuria is the most commonly recognized abnormality in renal disease. However, healthy domestic cats ( Felis catus ) excrete proteins at high concentrations (about 0.5 mg/ml) in their urine. We investigated the possible cause of proteinuria in healthy cats, and discovered a 70 kDa glycoprotein, which was excreted as a major urinary protein in cat urine, irrespective of gender. To elucidate the biochemical functions and the excretion mechanism of this protein, we cloned the cDNA for this protein from a cat kidney cDNA library. The deduced amino acid sequence shared 47% identity with the rat liver carboxylesterase (EC 3.1.1.1), and both the serine hydrolase active site and the carboxylesterase-specific sequence were conserved. Therefore we named this protein cauxin (carboxylesterase-like urinary excreted protein). In contrast to the mammalian carboxylesterases, most of which are localized within the cells of various organs, cauxin was expressed specifically in the epithelial cells of the distal tubules, and was secreted efficiently into the urine, probably because it lacked the endoplasmic reticulum retention sequence (HDEL). Based on our finding that cauxin is not expressed in the immature cat kidney, we conclude that cauxin is involved in physiological functions that are specific for mature cats. Recently, cauxin-like cDNAs were found from human brain and teratocarcinoma cells. These data suggest that cauxin and cauxin-like human proteins are categorized as a novel group of carboxylesterase multigene family. PMID:12401131

Miyazaki, Masao; Kamiie, Katsuyoshi; Soeta, Satoshi; Taira, Hideharu; Yamashita, Tetsuro

2003-02-15

166

Liver lead concentrations in raptors in New Jersey, USA, 2008-2010.  

PubMed

Lead exposure in New Jersey raptors was assessed by analyzing liver samples from carcasses obtained from wildlife rehabilitators. Samples were collected from 221 individuals representing 13 species. Concentrations were within the range of normal background exposure in 12 species. One red-tailed hawk had a liver lead concentration consistent with clinical poisoning (7.4 ?g/g wet weight), which represents an incidence of 1% (1/104) in that species and 0.5% (1/221) in the overall sample. A second red-tailed hawk had a liver lead concentration consistent with subclinical exposure (2.1 ?g/g wet weight). The combined incidence of elevated exposure (subclinical exposure + clinical poisoning) was 2% (2/104) in red-tailed hawks and 1% (2/221) in the overall sample. PMID:21647842

Stansley, William; Murphy, Lisa A

2011-06-07

167

An evaluation of the DRI-ETG EIA method for the determination of ethyl glucuronide concentrations in clinical and post-mortem urine.  

PubMed

A commercial enzyme immunoassay for the qualitative and semi-quantitative measurement of ethyl glucuronide (EtG) in urine was evaluated. Post-mortem (n=800), and clinical urine (n=200) samples were assayed using a Hitachi 902 analyzer. The determined concentrations were compared with those obtained using a previously published liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the quantification of EtG and ethyl sulfate. Using a cut-off of 0.5?µg/ml and LC-MS/MS limit of reporting of 0.1?µg/ml, there was a sensitivity of 60.8% and a specificity of 100% for clinical samples. For post-mortem samples, sensitivity and specificity were 82.4% and 97.1%, respectively. When reducing the cut-off to 0.1?µg/ml, the sensitivity and specificity were 83.3% and 100% for clinical samples whereas for post-mortem samples the sensitivity and specificity were 90.3 % and 88.3 %, respectively. The best trade-offs between sensitivity and specificity for LC-MS/MS limits of reporting of 0.5 and 0.1?µg/ml were achieved when using immunoassay cut-offs of 0.3 and 0.092?µg/ml, respectively. There was good correlation between quantitative results obtained by both methods but analysis of samples by LC-MS/MS gave higher concentrations than by enzyme immunoassay (EIA), with a statistically significant proportional bias (P<0.0001, Deming regression) for both sample types. The immunoassay is reliable for the qualitative and semi-quantitative presumptive detection of ethyl glucuronide in urine. PMID:22374825

Turfus, Sophie C; Vo, Tu; Niehaus, Nadia; Gerostamoulos, Dimitri; Beyer, Jochen

2012-02-28

168

Relationships between blood lead concentration and aminolevulinic acid dehydratase in alcoholics and workers industrially exposed to lead  

SciTech Connect

Blood lead concentration (Pb-B), aminolevulinic acid dehydratase (ALAD), and gamma-GT were measured in 265 workers industrially exposed to lead and in 184 patients with liver disease resulting from alcohol consumption. The first group was divided according to alcohol use, i.e., nondrinkers, moderate drinkers, and heavy drinkers. The second group was divided according to the following criteria: hepatopatic without cirrhosis, hepatopatic with compensated cirrhosis, and hepatopatic with decompensated cirrhosis. Heavy drinkers who were industrially exposed had the highest Pb-B (40.4 +/- 14.6 micrograms/dl) and the lowest ALAD (22.2 +/- 9.1 U/L). The correlations between Pb-B and ALAD show no significant change with the increase of Pb-B. In the alcoholic group, 76 patients with alcoholic liver disease without cirrhosis had the highest Pb-B (40.3-9.1 micrograms/dl) and ALAD the lowest (18.6 +/- 7.7 U/L). The negative correlation between Pb-B and log ALAD disappeared completely in individuals with Pb-B that exceeded 50 micrograms/dl, independent from the seriousness of illness.

Bortoli, A.; Fazzin, G.; Marin, V.; Trabuio, G.; Zotti, S.

1986-07-01

169

The behaviour of pharmaceuticals and heavy metals during struvite precipitation in urine.  

PubMed

Separating urine from wastewater at the source reduces the costs of extensive wastewater treatment. Recovering the nutrients from urine and reusing them for agricultural purposes adds resource saving to the benefits. Phosphate can be recovered in the form of struvite (magnesium ammonium phosphate). In this paper, the behaviour of pharmaceuticals and heavy metals during the precipitation of struvite in urine is studied. When precipitating struvite in urine spiked with hormones and non-ionic, acidic and basic pharmaceuticals, the hormones and pharmaceuticals remain in solution for more than 98%. For heavy metals, initial experiments were performed to study metal solubility in urine. Solubility is shown to be affected by the chemical conditions of stored and therefore hydrolysed urine. Thermodynamic modelling reveals low or very low equilibrium solute concentrations for cadmium (Cd), cobalt (Co), chromium (Cr), copper (Cu), nickel (Ni) and lead (Pb). Experiments confirmed Cd, Cu and Pb carbonate and hydroxide precipitation upon metal addition in stored urine with a reaction half-life of ca. 7 days. For all metals considered, the maximum specific metal concentrations per gram phosphate or nitrogen showed to be typically several orders of magnitudes lower in urine than in commercially available fertilizers and manure. Heavy metals in struvite precipitated from normal stored urine could not be detected. Phosphate recovery from urine over struvite precipitation is shown to render a product free from most organic micropollutants and containing only a fraction of the already low amounts of heavy metals in urine. PMID:17368503

Ronteltap, Mariska; Maurer, Max; Gujer, Willi

2007-03-26

170

Blood lead concentrations in waterfowl utilizing Lake Coeur d'Alene, Idaho.  

PubMed

The Coeur d'Alene River Basin, Lake Coeur d'Alene, and the Spokane River contain elevated heavy metal concentrations in sediment and water from historical mining and ore processing operations in the Coeur d'Alene Basin. Lead poisoning has been identified as the cause of death in hundreds of waterfowl utilizing wetlands in the floodplain of the Coeur d'Alene River, but little was known about hazards to waterfowl from heavy metal contamination in shallow bays and wetlands of Lake Coeur d'Alene. We examined lake sediment and blood lead concentrations in waterfowl utilizing Lake Coeur d'Alene, Idaho, to evaluate potential lead contamination of waterfowl utilizing the lake. We collected 56 palustrine and 102 lacustrine sediment samples and 61 mallard and 8 wood duck blood samples. Mean lead concentrations from palustrine and lacustrine sediment samples ranged from 14 to 3508 mg/kg dry weight (dw) and from 19 to 5009 mg/kg (dw), respectively. Lead concentrations in palustrine and lacustrine sediment from several Lake Coeur d'Alene bays were higher than those in lake reference areas and were higher than Bunker Hill Superfund Site target cleanup levels and suggested site-specific toxicity thresholds for swans. Mean blood lead from mallard and wood ducks sampled from Lake Coeur d'Alene bays were within lead toxicity ranges for waterfowl associated with clinical and severe clinical lead poisoning. We also collected 19 Canada goose and 3 mallard fecal samples to evaluate exposure through sediment ingestion. Waterfowl using Lake Coeur d'Alene appear to be exposed to lead by ingesting contaminated lake sediment. Our model predicts a sediment lead effects range of 147-944 mg/kg (dw) and mortality effects level of 1652 mg/kg (dw) for mallards utilizing Lake Coeur d'Alene. The locations of Harrison Slough, Powderhorn Bay, and Cottonwood Bay at the mouth of the Coeur d'Alene River and Blackwell Island and Cougar Bay near the Spokane River outflow of Lake Coeur d'Alene were the areas of greatest concern for waterfowl exposure to lead contaminated sediment. PMID:17082999

Spears, Brian L; Hansen, James A; Audet, Daniel J

2006-11-02

171

Urination - difficulty with flow  

MedlinePLUS

... urination, cloudy urine, and a sense of urgency (strong, sudden urge to urinate). Pay close attention to ... residual urine volume and to get urine for culture (a catheterized urine specimen ) Cystometrography Transrectal ultrasound of ...

172

Blood Lead Concentrations < 10 ?g\\/dL and Child Intelligence at 6 Years of Age  

Microsoft Academic Search

METHODS: Children were followed from 6 months to 6 years of age, with determination of blood lead concentrations at 6, 12, 18, and 24 months, and 3, 4, 5, and 6 years of age. At 6 years of age, intelligence was assessed in 194 children using the Wechsler Preschool and Primary Scale of Intelligence-Revised. We used general linear and semiparametic

Todd A. Jusko; Charles R. Henderson Jr.; Bruce P. Lanphear; Deborah A. Cory-Slechta; Patrick J. Parsons; Richard L. Canfield

2007-01-01

173

Both the Environment and Genes Are Important for Concentrations of Cadmium and Lead in Blood  

Microsoft Academic Search

Concentrations of cadmium and lead in blood (BCd and BPb, respectively) are traditionally used as biomarkers of environmental exposure. We estimated the influence of genetic factors on these markers in a cohort of 61 monozygotic and 103 dizygotic twin pairs (mean age = 68 years, range = 49-86). BCd and BPb were determined by graphite furnace atomic absorption spectrophotom- etry.

Lars Björkman; Marie Vahter; Nancy L. Pedersen

2000-01-01

174

Concentrations of selenium, mercury, and lead in blood of emperor geese in western Alaska  

USGS Publications Warehouse

We found up to 10 ppm wet weight of selenium in blood samples collected from emperor geese (Chen canagica) on their breeding grounds on the Yukona??Kuskokwim Delta in western Alaska, USA. Incubating adult females captured in late May through mid-June 1997 had significantly higher concentrations of selenium in their blood (mean = 5.60 ppm) than adult females captured during wing molt in late July 1996 (mean = 2.78 ppm). Females that nested early or were in good body condition had higher concentrations of selenium in their blood than did other nesting females. Blood samples from 4 of 29 goslings had detectable levels of selenium (mean = 0.14 ppm). Our findings suggest that emperor geese are exposed to more selenium in the marine environment of their wintering and staging areas on the Alaska Peninsula than on the breeding grounds. The highest concentration of mercury found in the blood of emperor geese was 0.24 ppm. One bird had a blood lead concentration of 0.67 ppm, but 82% had no detectable lead in their blood, suggesting that lead exposure from the ingestion of lead shot poses little threat for emperor geese in western Alaska, contrary to findings reported for sympatric spectacled eiders (Somateria fischeri).

Franson, J. C.; Schmutz, J. A.; Creekmore, L. H.; Fowler, A. C.

1999-01-01

175

Determination of 15N isotopic enrichment and concentrations of allantoin and uric acid in urine by gas chromatography/mass spectrometry.  

PubMed

A method for the determination of 15N enrichment and concentration of allantoin and uric acid simultaneously in urine using gas chromatography/mass spectrometry (GC/MS) is described. The urine samples contained [1,3-15N2] uric acid and its oxidation product allantoin. The uric acid and allantoin were isolated using an AG1-X8 (Cl-form) anion-exchange column and heated with a mixture containing 1:1 dimethylformamide and N-(tert-butyldimethylsilyl)-N-methyltrifluoroacetamide (MTBSTFA). The tert-butyldimethylsilyl (TBDMS) derivatives of allantoin and uric acid formed were injected into a gas chromatograph interfaced with a mass spectrometer operated under electron impact ionization conditions. Isotope ratio measurements were made from the abundance of the M-57 ions at m/z 398, 399 and 400 for allantoin and at m/z 567 and 569 for uric acid. 15N2 allantoin (99 at.%) was produced from [1,3-15N2] uric acid by treatment with uricase and used as a standard. Quantitation of allantoin and uric acid was based on isotopic dilution by spiking the urine sample with known quantities of 99 at.% [15N] uric acid and allantoin internal standards. The observed isotope ratio measurements from the prepared standards matched the theoretical values. Coefficients of variation in measurements of isotope ratio and concentration were 0.2 and 0.5%, respectively. The method was applied in a study to measure the urinary recovery of [1,3-15N2] uric acid continuously infused for 8-10 h into the blood of four sheep each on two occasions. Within 24 h, 65.9 +/- 9.1% of the tracer was excreted in the urine unchanged. Little was converted into allantoin (approximately 7% of the dose). The total recovery (5 days) of the infused tracer averaged 69.5 +/- 7.6% as uric acid and 76.8 +/- 9.3% as the sum of uric acid and allantoin. Uricase activities in plasma, liver and kidney of sheep were also measured using [1,3-15N2] uric acid as a substrate. Uricase activity was estimated to be 0.6 mU g-1 wet tissue in the liver and there appeared to be none in plasma and kidney. The low uricase activities in sheep tissues appeared to explain the limited conversion of the intravenously administered [15N] uric acid to allantoin but did not explain the large quantities of allantoin excreted in urine (8.96 +/- 0.86 and 1.36 +/- 0.25 mmol d-1 for allantoin and uric acid, respectively). The GC/MS method for the determination of 15N enrichment and concentration of allantoin and uric acid in urine is accurate and precise and provides a useful tool for studies on uric acid and allantoin metabolism. PMID:9487687

Chen, X B; Calder, A G; Prasitkusol, P; Kyle, D J; Jayasuriya, M C

1998-02-01

176

Blackcurrant seed press residue increases tocopherol concentrations in serum and stool whilst biomarkers in stool and urine indicate increased oxidative stress in human subjects.  

PubMed

Berry seeds are a tocopherol-rich by-product of fruit processing without specific commercial value. In a human intervention study, the physiological impact of blackcurrant seed press residue (PR) was tested. Thirty-six women (aged 24 +/- 3 years; twenty non-smokers, sixteen smokers) consumed 250 g bread/d containing 8% PR for a period of 4 weeks (period 3). Comparatively, a control bread without PR (250 g/d) was tested (period 2) and baseline data were obtained (period 1). Blood, stool and 24 h urine were collected during a 5 d standardised diet within each period. Tocopherol and Fe intakes were calculated from food intake. In serum, tocopherol concentration and Fe parameters were determined. In urine, oxidative stress markers 8-oxo-2'-deoxyguanosine, 8-iso-PGF2alpha and inflammatory response marker 15-keto-dihydro-PGF2alpha were analysed. Stool tocopherol concentration, genotoxicity of faecal water (comet assay) and antioxidant capacity of stool (aromatic hydroxylation of salicylic acid) were determined. Fe and total tocopherol intake, total tocopherol concentrations in serum and stool, and genotoxicity of faecal water increased with PR bread consumption (P < 0.05). The antioxidant capacity of stool decreased between baseline and intervention, expressed by increased formation of 2,3- and 2,5-dihydroxybenzoic acid in vitro (P < 0.05). In smokers, 8-oxo-2'-deoxyguanosine increased with PR consumption (P < 0.05). Prostane concentrations were unaffected by PR bread consumption. In summary, the intake of bread containing blackcurrant PR for 4 weeks increased serum and stool total tocopherol concentrations. However, various biomarkers indicated increased oxidative stress, suggesting that consumption of ground berry seed may not be of advantage. PMID:19302719

Helbig, Dorit; Wagner, Andreas; Glei, Michael; Basu, Samar; Schubert, Rainer; Jahreis, Gerhard

2009-03-23

177

Study of the effect of lactational bone loss on blood lead concentrations in humans.  

PubMed Central

Lactation and other clinical states of high bone turnover have been suggested to release lead (Pb) stored in bone into blood and tissues. Previous observations on the influences of lactation have been anecdotal, or at high blood Pb concentrations with varying past exposures, or complicated by postpartum fluid changes. A prospective observational study was performed to investigate possible changes in blood lead concentrations at multiple intervals during lactation for 6 months postpartum and to relate changes in blood lead concentrations to changes in bone density and other variables. Volunteer pregnant subjects (n = 58) were enrolled from a midwifery service at an academic public health hospital. Subjects were mostly Hispanic, recently immigrated, of low economic status, not receiving supplemental calcium, and had low blood Pb concentrations (2.35 +/- 2.05 microg/dl at enrollment). Bone density losses over 6 months for the group averaged -2.46 +/- 6.33% at the vertebral spine and -0.67 +/- 5.21% at the femoral neck. In predicting final bone density, apart from initial bone density only the total number of breast-feedings was a significant independent variable of the variables tested, accounting for an additional 12% of the variability. No changes in blood Pb concentrations were seen over the interval beyond 2 weeks postpartum (minimum detectable change was 0.4 microg/dl). There was no relation between the changes in bone density and changes in blood Pb or the integrated blood Pb over the 2-week to 6-month period. Normal (nonlactating) bone resorption rates contribute a large fraction of the Pb in blood during low-exposure circumstances. However, during lactation the increase in bone resorptive processes is probably relatively small with a larger decrease in deposition accounting for net bone loss, as suggested by other investigations. Thus, concomitant release of Pb from bones of lactating subjects with low blood lead concentrations on this background of high normal resorption was not large enough for detection. Images Figure 1

Osterloh, J D; Kelly, T J

1999-01-01

178

Methyl tert-Butyl Ether (MTBE) Detected in Abnormally High Concentrations in Postmortem Blood and Urine from Two Persons Found Dead Inside a Car Containing a Gasoline Spill.  

PubMed

Two deep frozen persons, a female and a male, were found dead in a car. There had been an explosive fire inside the car which had extinguished itself. On the floor inside the car were large pools of liquid which smelled of gasoline. The autopsy findings and routine toxicological analyses could not explain the cause of death. Carboxyhemoglobin levels in the blood samples were <10%. Analysis with a headspace gas chromatography revealed methyl tert-butyl ether (MTBE) concentrations of 185 mg/L (female victim) and 115 mg/L (male victim) in peripheral blood. The urine MTBE concentrations were 150 mg/L and 256 mg/L, respectively. MTBE is a synthetic chemical which is added to gasoline as a fuel oxygenate. Gasoline poisoning is likely to be the cause of the death in these two cases, and MTBE can be a suitable marker of gasoline exposure, when other volatile components have vaporized. PMID:23879346

Karinen, Ritva; Vindenes, Vigdis; Morild, Inge; Johnsen, Lene; Le Nygaard, Ilah; Christophersen, Asbjørg S

2013-07-23

179

Weight Loss Alters Organ Concentrations and Contents of Lead and Some Essential Divalent Metals in Rats Previously Exposed to Lead1'2  

Microsoft Academic Search

The loss of adipose tissue during energy restriction may be accompanied by a loss of lean body mass, including bone mass. Because most of the body lead burden is in the skeleton, we studied the effects of weight loss on the concentrations of lead in bone, blood and several organs in rats with prior but not cur rent lead exposure.

SHENGGAO HAN; XIANWEN QIAO; SCOTT SIMPSON; PEGAH AMERI; FRANCIS W. KEMP; JOHN D. BOGDEN

180

Effects of a Single Dose of Oral Iron on Hepcidin Concentrations in Human Urine and Serum Analyzed by a Robust LC-MS/MS Method  

PubMed Central

BACKGROUND The measurement of serum hepcidin, a peptide hormone that regulates iron metabolism, is clinically important to the understanding of iron homeostasis in health and disease. To date, the quantification of serum hepcidin levels by conventional immunological detection methods has proven problematic due to challenges in obtaining high quality antibodies which demonstrate good reproducibility. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF) has been employed recently for more sensitive quantification of hepcidin; however, this method has high background levels and therefore less than optimal specificity. METHODS In order to increase the specificity of the mass spectrometry based assay, we developed a robust, ultra-performance liquid-chromatography-tandem mass spectrometry (UPLC-MS/MS) protocol using multiple selected reaction monitoring (mSRM) for quantification of hepcidin levels in urine and serum of human subjects. With this assay, we assessed levels of hepcidin before and for up to 8 h after oral ingestion of ferrous sulfate in ten adult human subjects without known disease. RESULTS The linear response of hepcidin quantitation on each instrument was measured, and the correlation coefficients of these calibrations were r2 = 0.9512 ± 0.0202 (n=5) for urine and r2 = 0.9709 ± 0.0291 (n=5) for serum [r2= mean ± SD]. Compared to baseline, the levels of urinary hepcidin between 2-4 h and 4-8 h of both women and men showed significant increases with p < 0.05 and p < 0.001, respectively. The levels of serum hepcidin between 4 h and 8 h in both women and men showed significant increases, compared with baseline values, with both p < 0.01. Interestingly, we also observed some degree of oscillation of levels, occurring at later time points. CONCLUSIONS We have developed and validated a new method for measuring hepcidin concentrations in human serum and urine and used it to demonstrate early increases with iron supplement in both urinary and serum levels of hepcidin, which return to baseline levels, except in urine samples from men.

Hwang, Sun-Il; Lee, Yong-Yook; Park, Jung-Ok; Norton, H. James; Clemens, Elene; Schrum, Laura W.; Bonkovsky, Herbert L.

2011-01-01

181

Maternal and neonatal scalp hair concentrations of zinc, copper, cadmium, and lead  

Microsoft Academic Search

Postpartum scalp hair samples from 82 term-pregnancy mother\\/neonate pairs were analyzed for their concentration of zinc (Zn),\\u000a copper (Cu), cadmium (Cd), and lead (Pb), using inductively coupled plasma-mass spectrometry. Maternal and neonatal Zn concentrations\\u000a had geometric means (and 99% confidence intervals) of 122.5 ?g\\/g (117.9–131.5 ?g\\/g) and 146.9 ?g (141.5–156.7 ?g\\/g) respectively.\\u000a Corresponding Cu values were 18.4 ?g\\/g (17.6–23.8 ?g\\/g)

Ibrahim B.-A. Razagui; Ibrahim Ghribi

2005-01-01

182

Unique pattern of molt leads to low intraindividual variation in feather mercury concentrations in penguins.  

PubMed

The authors hypothesized that the catastrophic annual molt of penguins (Sphenisciformes) would lead to reduced intraindividual variation of mercury concentrations in body feathers. While mean mercury concentrations varied significantly among 8 penguin species, intraindividual variability did not differ among species and was 3 times lower than values observed in other seabirds. The findings of the present study suggest that a single body feather collected at random per individual can be adequate to estimate mercury exposure at the population level in penguins. Environ Toxicol Chem 2013;32:2331-2334. © 2013 SETAC. PMID:23761066

Brasso, Rebecka L; Drummond, Bridgette E; Borrett, Stuart R; Chiaradia, André; Polito, Michael J; Rey, Andrea Raya

2013-08-14

183

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

Microsoft Academic Search

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

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

2012-01-01

184

Blood concentration of essential trace elements and heavy metals in workers exposed to lead and cadmium.  

PubMed

The aim of the study was to determine blood concentration of essential trace elements (Se, Zn, Cu) and toxic metals (Pb, Cd), markers of antioxidant (activities of glutathione peroxidase (GPx), superoxidase dismutase and ceruloplasmin) and prooxidant processes (thiobarbituric acid reactive substances (TBARS)) in workers exposed to Pb and Cd. Forty three male workers of the lead-acid batteries department, aged 25-52 years, and twenty two workers, including 15 women, aged 36-51 years, exposed to Cd in the alkaline batteries department were examined. The reference group consisted of 52 healthy inhabitants of the same region. It was found that Se concentration and GPx activity in both erythrocytes and plasma of Cd exposed workers were significantly lower (p < 0.001) than in the reference group. We found an inverse linear correlation between blood Se and Cd concentrations in the workers exposed to Cd (r = -0.449; p < 0.01). Moreover, the activity of erythrocyte and plasma GPx was shown to be significantly lower in the study group of workers (p < 0.001). It was observed that TBARS concentration in plasma was significantly higher (p < 0.05) in the lead exposed workers than in the group without contact with Pb. Our results indicate that exposure to Pb and Cd affects the antioxidant potential of blood in workers exposed to heavy metals. PMID:11764849

Wasowicz, W; Gromadzi?ska, J; Rydzy?ski, K

2001-01-01

185

Urine culture  

MedlinePLUS

... lab to determine which, if any, bacteria or yeast are present in the urine. This takes 24 - ... positive" or abnormal test is when bacteria or yeast are found in the culture. This likely means ...

186

Spatial distribution of lead concentrations in urban surface soils of New Orleans, Louisiana USA.  

PubMed

Immediately following hurricane Katrina concern was raised over the environmental impact of floodwaters on the city of New Orleans, especially in regard to human health. Several studies were conducted to determine the actual contaminant distribution throughout the city and surrounding wetlands by analyzing soil, sediment, and water for a variety of contaminants including organics, inorganics, and biologics. Preliminary investigations by The Institute of Environmental and Human Health at Texas Tech University concluded that soils and sediments contained pesticides, semi-volatiles, and metals, specifically arsenic, iron, and lead, at concentrations that could pose a significant risk to human health. Additional studies on New Orleans floodwaters revealed similar constituents as well as compounds commonly found in gasoline. More recently, it has been revealed that lead (Pb), arsenic, and vanadium are found intermittently throughout the city at concentrations greater than the human health soil screening levels (HHSSLs) of 400, 22 (non-cancer endpoint) and 390 ?g/g, respectively. Of these, Pb appears to present the greatest exposure hazard to humans as a result of its extensive distribution in city soils. In this study, we spatially evaluated Pb concentrations across greater New Orleans surface soils. We established 128 sampling sites throughout New Orleans at approximately half-mile intervals. A soil sample was collected at each site and analyzed for Pb by ICP-AES. Soils from 19 (15%) of the sites had Pb concentrations exceeding the HHSSL threshold of 400 ?g/g. It was determined that the highest concentrations of Pb were found in the south and west portions of the city. Pb concentrations found throughout New Orleans in this study were then incorporated into a geographic information system to create a spatial distribution model that can be further used to predict Pb exposure to humans in the city. PMID:20054703

Abel, Michael T; Suedel, Burton; Presley, Steven M; Rainwater, Thomas R; Austin, Galen P; Cox, Stephen B; McDaniel, Les N; Rigdon, Richard; Goebel, Timothy; Zartman, Richard; Leftwich, Blair D; Anderson, Todd A; Kendall, Ronald J; Cobb, George P

2010-01-07

187

Blood Lead Concentrations in 1-3 Year Old Lebanese Children: A Cross-sectional study  

PubMed Central

Background Childhood lead poisoning has not made the list of national public health priorities in Lebanon. This study aims at identifying the prevalence and risk factors for elevated blood lead concentrations (B-Pb ? 100 ?g/L) among 1–3 year old children. It also examines the need for universal blood lead screening. Methods This is a cross-sectional study of 281 well children, presenting to the pediatric ambulatory services at the American University of Beirut Medical Center in 1997–98. Blood was drawn on participating children for lead analysis and a structured questionnaire was introduced to mothers asking about social, demographic, and residence characteristics, as well as potential risk factors for lead exposure. Children with B-Pb ? 100 ?g/L were compared to those with B-Pb < 100 ?g/L. Results Mean B-Pb was 66.0 ?g/L (median 60.0; range 10–160; standard deviation 26.3) with 39 (14%) children with B-Pb ? 100 ?g/L. Logistic regression analysis showed that elevated B-Pb was associated with paternal manual jobs (odds ratio [OR]: 4.74), residence being located in high traffic areas (OR: 4.59), summer season (OR: 4.39), using hot tap water for cooking (OR: 3.96), exposure to kohl (OR: 2.40), and living in older buildings (OR: 2.01). Conclusion Lead screening should be offered to high-risk children. With the recent ban of leaded gasoline in Lebanon, emphasis should shift to other sources of exposure in children.

Nuwayhid, Iman; Nabulsi, Mona; Muwakkit, Samar; Kouzi, Sarah; Salem, George; Mikati, Mohamed; Ariss, Majd

2003-01-01

188

Enzymatic Oxalate Determination in Urine  

Microsoft Academic Search

A methoddepending uponthe useof oxalicdecarboxylase isdescribed for the deter- minationofoxalic acidin urine. The urinaryoxalateexcretionof 25 healthypersons measured by this procedureis foundto average20.5 mg. (COOH)2\\/24 hr. In 70 patients with calculusdiseasethe oxalate titer of the urine was within the normal range. 1THE ACCURATE MEASUREMENT of oxalate concentration in urine pre- sents considerable difficulties. The methods available in the literature are based

Gerda G. Mayer; Deborah Markow; Frieda Karp

189

Degradation of TAB outer lead contacts due to the Au-concentration in eutectic tin\\/lead solder  

Microsoft Academic Search

The influence of the Au-concentration in OLB solder fillets on the contact reliability is shown. Quantitative analysis of the Au content shows a good accordance with the estimated concentrations using the geometrical data. The Au-concentration is the major influence factor on the thermal aging behavior of OLB contacts. A change in the failure mechanism due to Kirkendall porosity is observed

Elke Zakel; Ghassem Azdasht; Herbert Reichl

1994-01-01

190

Spatial analysis of bioavailable soil lead concentrations in Los Angeles, California.  

PubMed

Lead (Pb) poisoning causes permanent neurologic and developmental disorders and remains an important environmental health problem for US children, despite removal of Pb from gasoline and household paints. To better understand the contribution of Pb from historical traffic and residential Pb based paint to soil Pb concentrations in Los Angeles, we analyzed 550 soil Pb samples from south central Los Angeles County, CA, in relation to land-use patterns (commercial, industrial, residential, and parks and open areas) and proximity to freeways, highways, and major arterials. House age variables (surrogates of historical Pb-based paint) and traffic index variables (surrogates of historical traffic) were created at different buffer distances (10-5000m). Total and bioavailable Pb concentrations near freeways and major arterials were significantly higher than those collected elsewhere. Total and bioavailable Pb concentrations were highly correlated (r=0.96) after the removal of one outlier. Both parcel-age related variables and traffic variables were important predictors of current soil bioavailable Pb concentrations. Average age of parcels within 30m and length of small streets within 3000m explained 57% and 38% of the variance, respectively, in soil bioavailable Pb concentrations in residential areas away from freeways and major arterials (N=44). Road length of freeways within 750m explained 28% of bioavailable Pb concentrations in parks and open areas (N=26). Multi-variable regression models predicted 16-61% of the variances in bioavailable Pb concentrations, depending on land-use type and spatial relationship to roadways. Based on these models a map of spatial distributions of soil Pb concentrations was created for the Los Angeles area that shows promise as a screening tool to evaluate continued Pb poisoning in children. PMID:20219189

Wu, Jun; Edwards, Rufus; He, Xueqin Elaine; Liu, Zhen; Kleinman, Michael

2010-03-09

191

Lead  

Center for Food Safety and Applied Nutrition (CFSAN)

... Guidance for Industry: Lead in Candy Likely To Be Consumed Frequently by Small Children: Recommended Maximum Level and Enforcement ... More results from www.fda.gov/food/foodborneillnesscontaminants/metals

192

Blood Lead Levels and Serum Insulin-Like Growth Factor 1 Concentrations in Peripubertal Boys  

PubMed Central

Background: Childhood lead exposure has been associated with growth delay. However, the association between blood lead levels (BLLs) and insulin-like growth factor 1 (IGF-1) has not been characterized in a large cohort with low-level lead exposure. Methods: We recruited 394 boys 8–9 years of age from an industrial Russian town in 2003–2005 and followed them annually thereafter. We used linear regression models to estimate the association of baseline BLLs with serum IGF-1 concentration at two follow-up visits (ages 10–11 and 12–13 years), adjusting for demographic and socioeconomic covariates. Results: At study entry, median BLL was 3 ?g/dL (range, < 0.5–31 ?g/dL), most boys (86%) were prepubertal, and mean ± SD height and BMI z-scores were 0.14 ± 1.0 and –0.2 ± 1.3, respectively. After adjustment for covariates, the mean follow-up IGF-1 concentration was 29.2 ng/mL lower (95% CI: –43.8, –14.5) for boys with high versus low BLL (? 5 ?g/dL or < 5 ?g/dL); this difference persisted after further adjustment for pubertal status. The association of BLL with IGF-1 was stronger for mid-pubertal than prepubertal boys (p = 0.04). Relative to boys with BLLs < 2 ?g/dL, adjusted mean IGF-1 concentrations decreased by 12.8 ng/mL (95% CI: –29.9, 4.4) for boys with BLLs of 3–4 ?g/dL; 34.5 ng/mL (95% CI: –53.1, –16.0) for BLLs 5–9 ?g/dL; and 60.4 ng/mL (95% CI: –90.9, –29.9) for BLLs ? 10 ?g/dL. Conclusions: In peripubertal boys with low-level lead exposure, higher BLLs were associated with lower serum IGF-1. Inhibition of the hypothalamic–pituitary–growth axis may be one possible pathway by which lead exposure leads to growth delay.

Fleisch, Abby F.; Burns, Jane S.; Williams, Paige L.; Lee, Mary M.; Sergeyev, Oleg; Korrick, Susan A.

2013-01-01

193

Increased lead concentration in brain and potentiation of lead-induced neuronal depression in rats after combined treatment with lead and disulfiram  

SciTech Connect

The effects of disulfiram (tetraethylthiuram disulfide) on blood and brain lead levels and on lead-induced changes in growth and cerebellar Purkinje neuron excitability were assessed in adult Sprague-Dawley rats. Disulfiram is metabolized to diethyldithiocarbamate, which forms a lipophilic complex with lead, and can thereby influence the tissue distribution of lead. Pregnant rats were exposed to 0.25% lead acetate or an equimolar amount of sodium acetate in the drinking water, and these treatments were continued for 4 weeks after birth. Half of the mothers from each group were given 0.1 mmole/kg disulfiram orally twice a week until parturition, after which the treatment was continued for 4 weeks in the respective pups in the form of subcutaneous injections. Although lead exposure markedly increased blood lead levels, the increase in brain lead levels was much more modest. Disulfiram markedly increased brain lead levels while blood lead levels in this group were only slightly elevated as compared to animals receiving lead alone. In addition, the lead + disulfiram group had depressed weight gain during maturation, and Purkinje neuron firing rates were reduced. The lead alone and disulfiram alone groups were not different from controls in these respects. These data suggest that disulfiram potentiates the adverse effects of lead on growth rates and on cerebellar Purkinje neuron function by facilitating the accumulation of lead in brain tissue.

Oskarsson, A.; Olson, L.; Palmer, M.R.; Lind, B.; Bjoerklund, H.; Hoffer, B.

1985-12-01

194

The Human Urine Metabolome  

PubMed Central

Urine has long been a “favored” biofluid among metabolomics researchers. It is sterile, easy-to-obtain in large volumes, largely free from interfering proteins or lipids and chemically complex. However, this chemical complexity has also made urine a particularly difficult substrate to fully understand. As a biological waste material, urine typically contains metabolic breakdown products from a wide range of foods, drinks, drugs, environmental contaminants, endogenous waste metabolites and bacterial by-products. Many of these compounds are poorly characterized and poorly understood. In an effort to improve our understanding of this biofluid we have undertaken a comprehensive, quantitative, metabolome-wide characterization of human urine. This involved both computer-aided literature mining and comprehensive, quantitative experimental assessment/validation. The experimental portion employed NMR spectroscopy, gas chromatography mass spectrometry (GC-MS), direct flow injection mass spectrometry (DFI/LC-MS/MS), inductively coupled plasma mass spectrometry (ICP-MS) and high performance liquid chromatography (HPLC) experiments performed on multiple human urine samples. This multi-platform metabolomic analysis allowed us to identify 445 and quantify 378 unique urine metabolites or metabolite species. The different analytical platforms were able to identify (quantify) a total of: 209 (209) by NMR, 179 (85) by GC-MS, 127 (127) by DFI/LC-MS/MS, 40 (40) by ICP-MS and 10 (10) by HPLC. Our use of multiple metabolomics platforms and technologies allowed us to identify several previously unknown urine metabolites and to substantially enhance the level of metabolome coverage. It also allowed us to critically assess the relative strengths and weaknesses of different platforms or technologies. The literature review led to the identification and annotation of another 2206 urinary compounds and was used to help guide the subsequent experimental studies. An online database containing the complete set of 2651 confirmed human urine metabolite species, their structures (3079 in total), concentrations, related literature references and links to their known disease associations are freely available at http://www.urinemetabolome.ca.

Bouatra, Souhaila; Aziat, Farid; Mandal, Rupasri; Guo, An Chi; Wilson, Michael R.; Knox, Craig; Bjorndahl, Trent C.; Krishnamurthy, Ramanarayan; Saleem, Fozia; Liu, Philip; Dame, Zerihun T.; Poelzer, Jenna; Huynh, Jessica; Yallou, Faizath S.; Psychogios, Nick; Dong, Edison; Bogumil, Ralf; Roehring, Cornelia; Wishart, David S.

2013-01-01

195

Concentration and spatial distribution of lead in soil used for ammunition destruction.  

PubMed

Studies on heavy metal contamination in soils used for ammunition disposal and destruction are still emerging. The present study aimed to evaluate the contamination level and spatial distribution of lead in disposal and destruction areas. This site was used for ammunition disposal and destruction activities for 20 years. The ammunition destruction site (1,296 ha), a sampling system that followed a sampling grid (5 m × 5 m) with 30 points was adopted and samples were collected at the following five depths with a total of 150 samples. During the collection procedure, each sampling grid point was georeferenced using a topographic global positioning system. Data were validated through semivariogram and kriging models using Geostat software. The results demonstrated that the average lead value was 163 mg kg(-1), which was close to the investigation limit and the contamination levels were higher downstream than upstream. The results showed that there was lead contamination at the destruction site and that the contamination existed mainly at the surface layer depth. However, high lead concentrations were also found at deeper soil depths in the destruction area due to frequent detonations. According to the planimetry data, the areas that require intervention significantly decreased with increasing depths in the following order: 582.7 m(2) in the 0-20 cm layer; 194.6 m(2) in the 20-40 cm layer; 101.6 m(2) in the 40-60 cm layer; and 45.3 m(2) in the 60-80 cm layer. PMID:22903201

do Nascimento Guedes, Jair; do Amaral Sobrinho, Nelson Moura Brasil; Ceddia, Marcos Bacis; Vilella, André Luis Oliveira; Tolón-Becerra, Alfredo; Lastra-Bravo, Xavier Bolívar

2012-08-18

196

Updating about reductions of air and blood lead concentrations in Turin, Italy, following reductions in the lead content of gasoline  

SciTech Connect

Considering its well known toxicity and the chronic human exposure to lead, international lawmakers enforced some directives or laws calling for the reduction of lead content in gasoline. All of these legislative acts aimed to reduce health risks for the general population. The aim of this study was to consider the effectiveness of these laws on air lead levels and consequently on blood lead levels in a randomly selected urban Italian population. In particular, these markers were analyzed over the course of several years, corresponding to the periods just before and after enforcements of the reductions of lead in petrol. Data presented point out some considerations: (1) enforcement of legislative measures concerning the reduction of lead in petrol has reduced atmospheric levels of lead. This result demonstrates a major environmental success in primary prevention efforts. (2) This success is clear especially considering that the actual Pb-B levels can be extended to the urbanized populations. Pb-B levels were consistently higher for drinkers, for older adults and for males. The mean of Pb-B level for the present urbanized population is higher than the U.S. overall population (6.4 vs 3 {mu}g/dl). This difference can be also explained considering the different historical period of enforcement of the restriction laws. 10 refs., 3 figs., 3 tabs.

Bono, R.; Pignata, C.; Gilli, G. [Univ. of Turin (Italy)] [and others

1995-07-01

197

Degradation Of Tab Outer Lead Contacts Due To The Au Concentration In Eutectic Tin\\/lead Solder  

Microsoft Academic Search

The influence of the Au-concentration in OLB-solder fillets on the contact reliability is shown. The quantitative analysis of the AUcontent is in accordance with the estimated concentrations using the geometrical data. The Au-concentration is the major influence factor on the thermal aging behaviour of OLB-contacts. A change in the failure mechanism due to Kirkendall porosity is observed if a AUconcentration

E. Zakel; G. Azdasht; H. Reich

1993-01-01

198

DDE, PCBs, cadmium, lead, and mercury concentrations in rhinoceros auklets from Washington  

USGS Publications Warehouse

In July 1981, 5 adult rhinoceros auklets (Cerorhinca monocerata) were captured on the ground near nesting areas on each of Protection and Destruction Islands, Washington. The birds were euthanized, and their livers and kidneys removed and analyzed. Levels (I?g / g wet weight) of DDE (0.11 to 0.95), polychlorinated biphenyls (no residue detected [ND] to 1.1), mercury (0.60 to 1.8), and lead (ND to 0.85) in livers and cadmium (9.1 to 21.9) in kidneys were similar in each colony. All concentrations were less than known effect levels.

Blus, L. J.; Fitzner, R. E.; Leschner, L. L.; Wilson, U. W.

1999-01-01

199

Impact of unleaded gasoline introduction on the concentration of lead in the air of Dhaka, Bangladesh.  

PubMed

Airborne particulate matter (APM) samples collected at a semiresidential area in Dhaka, Bangladesh, during the periods of 1994 and 1997-2000 have been studied to assess the impact of the use of unleaded gasoline in Bangladesh. According to scanning electron microscopy/ energy-dispersive X-ray microanalyzer studies, lead (Pb) was found as Pb sulfates and Pb halides in motor-vehicle exhaust particles, whose diameters were some hundreds of nanometers. No significant changes in the annual averages of APM mass and black carbon concentrations have been observed over the period. The yearly average Pb concentration reached a maximum value of 370 ng/m3 in the particulate matter with an aerodynamic diameter < 2.5 microm fraction in 1998. In 2000, the concentration decreased to approximately one-third (106 ng/m3) of the high earlier values after the introduction of unleaded gasoline in 1999. A significant lowering of the blood Pb level of the population over next few years is expected as a result of this great decrease in Pb concentration. PMID:14649755

Biswas, Swapan K; Tarafdar, Solaiman A; Islam, Ashraful; Khaliquzzaman, Mohammed; Tervahattu, Heikki; Kupiainen, Kaarle

2003-11-01

200

Maternal blood lead concentration, diet during pregnancy, and anthropometry predict neonatal blood lead in a socioeconomically disadvantaged population.  

PubMed Central

To determine the influences of maternal diet and nutrition during pregnancy on the blood lead level of neonates, we conducted a study of mother-infant pairs from lower socioeconomic circumstances living in Albany County, New York. Maternal blood lead (MBPb), anthropometry, and diet were assessed in each trimester. Neonates' blood lead (NBPb) levels were low (geometric mean = 1.58 micro g/dL), and none had elevated blood lead. More than 50% of the mothers had intakes below the recommended dietary allowances for zinc, calcium, iron, vitamin D, and kilocalories. As expected, MBPb was strongly and positively related to NBPb. Among the anthropometric measures of maternal nutritional status, variables measuring gain in weight and arm circumference were negatively related to NBPb. In multivariable models reflecting different analytic strageties and including MBPb, anthropometry, and sociodemographic characteristics, dietary intakes of iron and vitamin D were negatively related to NBPb. The effect of zinc varied substantially depending on model covariates. Effects of dietary constituents are difficult to distinguish, given the intercorrelated nature of nutrients in the diet. Nevertheless, the influences of maternal anthropometric variables, iron, and vitamin D on neonatal lead levels are clear in our analyses.

Schell, Lawrence M; Denham, Melinda; Stark, Alice D; Gomez, Marta; Ravenscroft, Julia; Parsons, Patrick J; Aydermir, Aida; Samelson, Renee

2003-01-01

201

The factors influencing direct spectral fluorimetry of some urine metabolites.  

PubMed

Urine contains a variety of organic and inorganic chemicals including a number of natural fluorophores. Most of them are formed by tryptophan metabolites. But there are also metabolites of riboflavin, catecholamines and porphyrins. The alternation in the autofluorescence of urine and the alternation in the concentration of these substances are developed by both physiological and pathological changes such as disorder of body metabolism, dietary intake, age and etc. In this work we present fluorescent properties of chosen urine fluorophores - i.e. 5-hydroxyindole-3-acetic acid (5-HIAA), indoxyl sulphate (urine indican), serotonin (5-HT), vanillylmandelic (VMA) and homovanillic (HVA) acids typical for various diseases. Differences of fluorescent parameters of individual fluorophores measured in vitro in the water solutions and in natural environment of urine are significant and can lead to false results and conclusions. Therefore, we present the most common influence that can occur in urine (e.g. pH, ionic strength, proteins, and other fluorophores). The aim is to elaborate the exact "know-how" for direct complex fluorescent measurement in urine related to particular diagnoses. PMID:21189166

Lichardusová, L; Kušnír, J; Valko-Rokytovská, M; Mareková, M

2010-01-01

202

Lead concentrations and isotopes in corals and water near Bermuda, 1780-2000  

NASA Astrophysics Data System (ADS)

The history of the oceanic anthropogenic lead (Pb) transient in the North Atlantic Ocean for the past 220 yr is documented here from measurements of Pb concentration and isotope ratios from annually-banded corals that grew in coastal seawaters near Bermuda and from seawater samples collected during the last 20 yr of the 20th century. Anthropogenic Pb emissions in this area have been dominated by the industrialization of North America beginning in the 1840s, the introduction of leaded gasoline beginning in the 1920s and its phase-out that began in the mid-1970s. The phase-out of leaded gasoline was largely completed by the late 1990s. Coral Pb concentrations occur at a constant low level of about 5 nmol Pb/mol Ca (~ 15 pmol/kg in seawater) from the late 1700s to ~ 1850. From ~ 1850 to ~ 1900 there is a small increase rising to a plateau at ~ 25 nmol Pb/mol Ca (~ 80 pmol/kg in seawater) in the 1930s until the late 1940s, at which point Pb concentrations rapidly increase to ~ 60 nmol Pb/mol Ca (~ 200 pmol/kg in seawater). In the mid 1970s, Pb began to decline to ~ 25 nmol Pb/Ca (40 pmol/kg in seawater) by the end of the 20th century, comparable to levels occurring in the early 20th century. Pb isotope ratios (Pb I.R.) show maximum 206Pb/207Pb = 1.21 and 208Pb/207Pb = 2.49 in the middle of the 19th century. We conclude that this signal is a reflection of the early dominance of Upper Mississippi Valley Pb ore in the United States, as previously seen in the estuarine sediments of Rhode Island. After 1900, Pb I.R. decrease only slightly until the 1960s when there is a significant local maximum in the 1970s to 206Pb/207Pb = 1.19 and 208Pb/207Pb = 2.45 as low-Pb I.R. sources were phased out in the United States. Then, as US leaded gasoline utilization decreased more rapidly than European Pb gas utilization (which has lower Pb I.R.), western North Atlantic Pb I.R. decreased to 206Pb/207Pb = 1.17 and 208Pb/207Pb = 2.44, their lowest values in the past two centuries.

Kelly, Amy E.; Reuer, Matthew K.; Goodkin, Nathalie F.; Boyle, Edward A.

2009-06-01

203

VAPORIZATION OF ELEMENTAL MERCURY FROM POOLS OF MOLTEN LEAD AT LOW CONCENTRATIONS.  

SciTech Connect

Should coolant accidentally be lost to the APT (Accelerator Production of Tritium) blanket and target, and the decay heat in the target be deposited in the surrounding blanket by thermal radiation, temperatures in the blanket modules could exceed structural limits and cause a physical collapse of the blanket modules into a non-coolable geometry. Such a sequence of unmitigated events could result in some melting of the APT blanket and create the potential for the release of mercury into the target-blanket cavity air space. Experiments were conducted which simulate such hypothetical accident conditions in order to measure the rate of vaporization of elemental mercury from pools of molten lead to quantify the possible severe accident source term for the APT blanket region. Molten pools of from 0.01% to 0.10% mercury in lead were prepared under inert conditions. Experiments were conducted, which varied in duration from several hours to as long as a month, to measure the mercury vaporization from the lead pools. The melt pools and gas atmospheres were held fixed at 340 C during the tests. Parameters which were varied in the tests included the mercury concentration, gas flow rate over the melt and agitation of the melt, gas atmosphere composition and the addition of aluminum to the melt. The vaporization of mercury was found to scale roughly linearly with the concentration of mercury in the pool. Variations in the gas flow rates were not found to have any effect on the mass transfer, however agitation of the melt by a submerged stirrer did enhance the mercury vaporization rate. The rate of mercury vaporization with an argon (inert) atmosphere was found to exceed that for an air (oxidizing) atmosphere by as much as a factor of from ten to 20; the causal factor in this variation was the formation of an oxide layer over the melt pool with the air atmosphere which served to retard mass transfer across the melt-atmosphere interface. Aluminum was introduced into the melt to investigate its effect upon the mercury vaporization rate in simulation of the aluminum structure in the APT blanket. No effect at all was observed for a case with an argon atmosphere. This suggests that there are no chemical effects of the aluminum on the vaporization kinetics. With an air atmosphere, the presence of aluminum in the melt reduced the mercury vaporization by a factor of six in comparison to the identical test but without aluminum present. This suggests that aluminum in the lead/mercury .melt retards the vaporization of mercury by creating a surface oxide layer in addition to the lead-oxide layer which increases the mass transfer resistance.

GREENE,G.A.; FINFROCK,C.C.

2000-10-01

204

Determination of lead concentration and film thickness in electroluminescent calcium sulfide thin films by X-ray fluorescence  

Microsoft Academic Search

For the analysis of electroluminescent thin films, X-ray fluorescence (XRF) provides a convenient method as both the concentration of the dopant and the film thickness can be determined rapidly and non-destructively. An XRF method for the determination of thickness and lead concentration in lead doped calcium sulfide thin films was developed. Calibration standards made of polyvinyl alcohol and gelatin as

Sari Lehto; Lauri NiinistiJ; Inkeri Yliruokanen

1993-01-01

205

Polymorphisms in Genes Encoding Potential Mercury Transporters and Urine Mercury Concentrations in Populations Exposed to Mercury Vapor from Gold Mining  

PubMed Central

Background: Elemental mercury (Hg0) is widely used in small-scale gold mining. Persons working or living in mining areas have high urinary concentrations of Hg (U-Hg). Differences in genes encoding potential Hg-transporters may affect uptake and elimination of Hg. Objective: We aimed to identify single nucleotide polymorphisms (SNPs) in Hg-transporter genes that modify U-Hg. Methods: Men and women (1,017) from Indonesia, the Philippines, Tanzania, and Zimbabwe were classified either as controls (no Hg exposure from gold mining) or as having low (living in a gold-mining area) or high exposure (working as gold miners). U-Hg was analyzed by cold-vapor atomic absorption spectrometry. Eighteen SNPs in eight Hg-transporter genes were analyzed. Results: U-Hg concentrations were higher among ABCC2/MRP2 rs1885301 A–allele carriers than among GG homozygotes in all populations, though differences were not statistically significant in most cases. MRP2 SNPs showed particularly strong associations with U-Hg in the subgroup with highest exposure (miners in Zimbabwe), whereas rs1885301 A–allele carriers had higher U-Hg than GG homozygotes [geometric mean (GM): 36.4 µg/g creatinine vs. 21.9; p = 0.027], rs2273697 GG homozygotes had higher U-Hg than A–allele carriers (GM: 37.4 vs. 16.7; p = 0.001), and rs717620 A–allele carriers had higher U-Hg than GG homozygotes (GM: 83 vs. 28; p = 0.084). The SLC7A5/LAT1 rs33916661 GG genotype was associated with higher U-Hg in all populations (statistically significant for all Tanzanians combined). SNPs in SLC22A6/OAT1 (rs4149170) and SLC22A8/OAT3 (rs4149182) were associated with U-Hg mainly in the Tanzanian study groups. Conclusions: SNPs in putative Hg-transporter genes may influence U-Hg concentrations.

Ameer, Shegufta; Bernaudat, Ludovic; Drasch, Gustav; Baeuml, Jennifer; Skerfving, Staffan; Bose-O'Reilly, Stephan; Broberg, Karin

2012-01-01

206

Chemical concentrations of pollutant lead aerosols, terrestrial dusts and sea salts in Greenland and Antarctic snow strata  

Microsoft Academic Search

In this study we report analyses of lead in annual ice layers from the interior of northern Greenland and in annual layers of ice from the interior of the Antarctic continent. We show that lead concentrations increase from 0.200 Pb\\/kg ice today in north pole ice sheets, the sharpest rise occurring after 1940, and that the levels of lead in

M. Murozumi; Tsaihwa J. Chow; C. Patterson

1969-01-01

207

Concentration dependence of surface properties and molar volume of multicomponent system indium-tin-lead-bismuth  

NASA Astrophysics Data System (ADS)

The results of an experimental research of surface properties of the four-component system indium-tin-lead-bismuth are presented. The researches under discussion were carried out in a combined device in which the surface tension (?) is measured by the method of maximum pressure in a drop, and density (?) is measured by advanced aerometry. Measurement errors are 0.7 % for surface tension measurement, and 0.2 % for density measurement. The study of the concentration dependence of ? in this system has revealed the influence of the third and fourth components upon the characteristics of surface tension isotherms of the binary system indium-tin. It was found out that with an increase in the content of the third and fourth components the depth of the minimum on the surface tension isotherms of the indium-tin system ? decreases. On the basis of the concentration dependence of the phenomenon of concentration bufferity is revealed. It is shown that despite the complex character, isotherms of ? on beam sections of a multicomponent system do not contain qualitatively new features in comparison with the isotherms of these properties in lateral binary systems.

R, Dadashev; R, Kutuev; D, Elimkhanov

2008-02-01

208

Zinc Protoporphyrin IX Concentrations between Normal Adults and the Lead-Exposed Workers Measured by HPLC, Spectrofluorometer, and Hematofluorometer  

Microsoft Academic Search

To establish the relationship between Zinc protoporphyrin (ZPP) concentrations and blood lead (PbB) levels and to identify reliable analytical methods of ZPP and Protoporhyrin (PP), blood samples were obtained from 263 office workers without the history of occupational lead exposure and 49 lead-acid battery workers. The mean concentrations of PbB for the normal adults and the battery workers were 9.26

Young-Man ROH; Kangyoon KIM; Hyunwook KIM

2000-01-01

209

Cotinine concentrations in follicular fluid as a measure of secondhand tobacco smoke exposure in women undergoing in vitro fertilization: Inter-matrix comparisons with urine and temporal variability  

Microsoft Academic Search

We examined the relationship between cotinine measures in follicular fluid (FF) and urine to inform our exposure assessment strategy for an ongoing epidemiological study of secondhand tobacco smoke (STS) exposure and early pregnancy loss. Among subjects undergoing in vitro fertilization (IVF), we compared cotinine levels in paired urine and FF samples from the same women and examined FF cotinine levels

Merle D. Benedict; Stacey A. Missmer; Allison F. Vitonis; Daniel W. Cramer; John D. Meeker

2011-01-01

210

Concentration of Fluorine in the Urine of Individuals from the General Population and in Exposed Individual Workman. Techniques and Results; CONCENTRAZIONE DI FLUORO NELLE URINE DI INDIVIDUI DELLA COMUNE POPOLAZIONE E DI INDIVIDUI PROFESSIONALMENTE ESPOSTI. TECHNICHE E RISULTATI  

Microsoft Academic Search

The colorimetric method for the determination of fluorine with zirconium-; eriochromocyanine R was modified to adapt it to the analyses of any type of ; material of toxicological importance. HClOâ and AgClOâ is added to ; urine brought to dryness in the presence of CaO; and then it is distilled until ; 70 to 100 cc of the liquid is

M. Giubileo; V. Camera

1961-01-01

211

Factors controlling elevated lead concentrations in water samples from aquifer systems in Florida  

USGS Publications Warehouse

Concentrations of total lead (Pb) and dissolved Pb exceeded the U.S. Environmental Protection Agency action level of 15 micrograms per liter (mg/L) in approximately 19 percent and 1.3 percent, respectively, of ground-water samples collected during 1991-96 from a statewide network of monitoring wells designed to delineate background water quality of Florida's major aquifer systems. Differences in total Pb concentrations among aquifer systems reflect the combined influence of anthropogenic sources and chemical conditions in each system. A highly significant (p<0.001) difference in median total Pb concentrations was found for water samples from wells with water-level recording devices that contain Pb-counterweights (14 mg/L) compared to non-recorder wells (2 mg/L). Differences between total Pb concentrations for recorder and non-recorder wells are even more pronounced when compared for each aquifer system. The largest differences for recorder status are found for the surficial aquifer system, where median total Pb concentrations are 44 and 2.4 mg/L for recorder wells and non-recorder wells, respectively. Leaching of Pb from metal casing materials is another potential source of Pb in ground water samples. Median total Pb concentrations in water samples from the surficial, intermediate, and Floridan aquifer systems are higher from recorder wells cased with black iron than for recorder wells with steel and PVC casing material. Stable isotopes of Pb were used in this study to distinguish between anthropogenic and natural sources of Pb in ground water, as Pb retains the isotopic signature of the source from which it is derived. Based on similarities between slopes and intercepts of trend lines for various sample types (plots of 206Pb/204Pb versus 208Pb/204Pb and 207Pb/204Pb versus 208Pb/204Pb) the predominant source of total Pb in water samples from the surficial aquifer system is corrosion of Pb counterweights. It is likely that only ground-water samples, not the aquifer, were contaminated with elevated Pb concentations. Pb-isotopic ratios of water from the Floridan aquifer system plot between trend lines connecting the isotopic composition of Pb counterweights and the composition of acid leachates of material from the Floridan aquifer system, indicating that Pb in these waters most likely is a mixture of Pb derived from aquifer material and corrosion of Pb counterweights.

Katz, B. G.; Bullen, M. P.; Bullen, T. D.; Hansard, Paul

1999-01-01

212

On-line preconcentration system coupled to electrothermal atomic absorption spectrometry for the simultaneous determination of bismuth, cadmium, and lead in urine  

Microsoft Academic Search

A laboratory-made flow injection (FI) system coupled to a multi-element electrothermal atomic absorption spectrometer (ETAAS, SIMMA 6000) was used to determine Bi, Cd, and Pb simultaneously in urine. A on-line preconcentration procedure was controlled by a personal computer. A miniature Muromac A-1 resin column was inserted at the top of the AS-72 autosampler arm. A modified AS-72 autosampler in the

Yu-Hsiang Sung; Shang-Da Huang

2003-01-01

213

Both the environment and genes are important for concentrations of cadmium and lead in blood.  

PubMed Central

Concentrations of cadmium and lead in blood (BCd and BPb, respectively) are traditionally used as biomarkers of environmental exposure. We estimated the influence of genetic factors on these markers in a cohort of 61 monozygotic and 103 dizygotic twin pairs (mean age = 68 years, range = 49-86). BCd and BPb were determined by graphite furnace atomic absorption spectrophotometry. Variations in both BCd and BPb were influenced by not only environmental but also genetic factors. Interestingly, the genetic influence was considerably greater for nonsmoking women (h(2) = 65% for BCd and 58% for BPb) than for nonsmoking men (13 and 0%, respectively). The shared familial environmental (c(2)) influence for BPb was 37% for men but only 3% for women. The association between BCd and BPb could be attributed entirely to environmental factors of mutual importance for levels of the two metals. Thus, blood metal concentrations in women reflect not only exposure, as previously believed, but to a considerable extent hereditary factors possibly related to uptake and storage. Further steps should focus on identification of these genetic factors and evaluation of whether women are more susceptible to exposure to toxic metals than men. Images Figure 1 Figure 2

Bjorkman, L; Vahter, M; Pedersen, N L

2000-01-01

214

Elevated lead concentrations in Japanese ribs of the Edo era (300-120 BP).  

PubMed

Nineteen elements (Al, B, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, P, Pb, Sr, Ti, V and Zn) were analyzed in excavated bone (rib) of the Edo era (a Japanese historical era, 300-120 BP (before present] from different burial conditions in Tokyo, and in contemporary Japanese bone (rib) obtained from autopsy cases. The elemental composition of the excavated bones varied according to their burial conditions. The concentration of soil-related elements such as Fe, Mn, Co and Ti in the bone was lowest in the samples in the "wooden coffin in a stone room", next lowest in the "funeral urn with mud", and highest in the "wooden coffin full of mud". The Pb concentration was higher in excavated bones than in contemporary bones and much higher, by as much as several tens micrograms/g, in the bones in the "wooden coffin in a stone room" and in the "funeral urn with mud". These results strongly support the notion that Japanese in the city of Edo were highly polluted by environmental lead. PMID:3238418

Kosugi, H; Hanihara, K; Suzuki, T; Hongo, T; Yoshinaga, J; Morita, M

1988-10-15

215

Changing Trends in the Epidemiology of Pediatric Lead Exposure: Interrelationship of Blood Lead and ZPP Concentrations and a Comparison to the US Population  

PubMed Central

Summary Objectives To determine blood lead and zinc protoporphyrin (ZPP) concentrations in a pediatric population, confirm their interrelationship at low blood lead concentrations, and assess changing trends through comparison of these data with those found in a similar population 10 years earlier and to US national values. Study Design and Methods The study was conducted in a large pediatric hospital in the Washington DC area (CNMC) on patient whole blood specimens (n = 4908) (0–17 years) accrued from January 2001 to June 2002. Pediatric blood lead concentrations were determined by atomic absorption spectrophotometry, and ZPP by hematofluorometry. The data were analyzed using a computer adaptation of the Hoffmann approach. Results and Conclusions Blood lead level (BLL) means ranged between 2.2 and 3.3 ?g/dL, and the median BLL was 3 ?g/dL throughout. Mean ZPP concentrations ranged between 21.1 and 26.6 ?g/dL and the median concentrations between 21 and 27 ?g/dL. In comparison to data obtained from a similar pediatric population at CNMC between 1991 and 1992, pediatric BLLs have significantly declined in the Washington DC area. The current data are also compared with data obtained from the National Health and Nutrition Examination Survey (NHANES III) of the US population. The interrelationship between ZPP and BLLs is examined.

Soldin, Offie Porat; Pezzullo, John C.; Hanak, Brian; Miller, Maureen; Soldin, Steven J.

2013-01-01

216

Penicillin concentrations in serum, milk, and urine following intramuscular and subcutaneous administration of increasing doses of procaine penicillin G in lactating dairy cows.  

PubMed Central

Eight healthy, non-pregnant, crossbred Holstein dairy cows (557-682 kg) within their first 3 months of lactation (13-21.5 kg of milk/day) were used. Cows were kept in tie stalls for the whole experiment. The 8 cows were randomly assigned to 2 (IM and SC) 4 x 4 balanced Latin square design experiments. Doses of procaine penicillin G (PPG) (300000 IU/mL) in each square were 7000, 14000, 21000 and 28000 IU/kg and were injected IM or SC once daily for 5 consecutive days. Volumes of PPG per site of injection never exceeded 20 mL. Blood was collected to determine the Cmax, Tmax, and AUC; urine and milk were also taken to measure the persistence of PPG in these fluids. Results show that serum Cmax and Tmax were only slightly affected by increasing the doses or the route of administration, whereas the AUC was linearly increased in relation to the dose injected in both modes of injection. In the urine, Cmax varied from 160 to 388 IU/mL and Tmax from 72-120 h during 5 consecutive days of PPG injection. A dose effect in Cmax was observed only for the IM route of administration and no variation (P > 0.05) was found between the IM and SC routes. Milk Cmax concentrations were only increased by the dose regimen in the IM group. At doses of 21000 and 28000 IU/kg, the IM group had a higher (P > 0.05) Cmax when compared with the SC groups. Milk PPG residues were not detectable over 96 h following the last IM injection, independently of the dose injected. However milk PPG residues were detected for up to 132 h following the last SC injection. These results show that when PPG is injected IM once daily in volumes not exceeding 20 mL/site at doses as high as 28000 IU/kg, the withdrawal period should be at least 96 h. Therefore, in the present model, there was no advantage to inject PPG by SC route to improve PPG kinetic parameters as the AUC, Cmax, or Tmax.

Dubreuil, P; Daigneault, J; Couture, Y; Guay, P; Landry, D

2001-01-01

217

Urine 24-hour volume  

MedlinePLUS

Urine volume; 24-hour urine collection ... A 24-hour urine sample is needed. On day 1, urinate into the toilet when you get up in ... urine in a special container for the next 24 hours. On day 2, urinate into the container ...

218

Enhancing Potentially Plant-Available Lead Concentrations in Contaminated Residential Soils Using a Biodegradable Chelating Agent  

NASA Astrophysics Data System (ADS)

Chelation of heavy metals is an important factor in enhancing metal solubility and, hence, metal availability to plants to promote phytoremediation. In the present study, we compared the effects of application of a biodegradable chelating agent, namely, ethylenediaminedisuccinic acid (EDDS) on enhancing plant available form of lead (Pb) in Pb-based paint contaminated residential soils compared to that of a more commonly used, but non-biodegradable chelate, i.e., ethylenediaminetetraacetic acid (EDTA). Development of a successful phytoremediation model for metals such as Pb depends on a thorough understanding of the physical and chemical properties of the soil, along with the optimization of a chelate treatment to mobilize Pb from `unavailable' pools to potentially plant available fraction. In this context, we set out to perform batch incubation experiments to investigate the effectiveness of the two aforementioned chelates in enhancing plant available Pb at four different concentrations (0, 5, 10 and 15 mM/kg soil) and three treatment durations (0, 10 and 30 days). We selected 12 contaminated residential soils from two major metropolitan areas (San Antonio, TX and Baltimore, MD) with varying soil physico-chemical properties - the soils from San Antonio were primarily alkaline and those from Baltimore were typically acidic. Total soil Pb concentrations ranged between 256 mg/kg and 4,182 mg/kg. Our results show that both chelates increased the solubility of Pb, otherwise occluded in the complex soil matrix. For both EDTA and EDDS, the exchangeable concentrations of soil Pb also increased with increase in chelate concentration and incubation time. The most effective treatment was 15 mM chelate kg-1 soil incubated for 30 days, which caused many fold increase in potentially plant available Pb (a combination of the soluble and exchangeable fractions) relative to the unamended controls. Step wise multiple linear regression analysis using chelate-extractable Pb and soil properties showed that plant available Pb fraction could be assessed from the two inter-related soil parameters: soil organic matter and soil pH. Although EDTA was more effective in Pb solubilization than EDDS, the rapid kinetics of the Pb-EDTA complexation process and the prolonged persistence of EDTA in soils pose a potential groundwater contamination problem via metal leaching. In contrast to EDTA, EDDS addition caused relatively slow release of Pb from the soil matrix. The biodegradable nature (and short half life) of EDDS in soils makes it a promising chelating agent for use as soil amendment to enhance Pb solubilization and hence, potential plant uptake.

Andra, S.; Datta, R.; Sarkar, D.; Saminathan, S.

2007-12-01

219

Increased concentrations of genotype-interpreted Ca 19-9 in urine of bladder cancer patients mark diffuse atypia of the urothelium  

Microsoft Academic Search

We investigated the use of genotype-interpreted mea- surements of the tumor marker Ca 19-9 in the urine of bladder cancer patients as a marker of the extent of urothelial disease. Ca 19-9 in urine (sialyl-Lea\\/creatinine ratio) was measured in 81 bladder cancer patients and correlated to T-category, histologic grade, and presence of urothelial dysplasia. As reference group, Ca 19-9 ratio

Else Marie Vestergaard; Hans Wolf; Torben F. Ørntoft

220

Cadmium, lead and zinc concentrations in water, sediment and oyster (Crassostrea virginica) of San Andres Lagoon, Mexico.  

PubMed

The spatial distribution of cadmium, lead and zinc concentrations in water, sediment and oysters from San Andres Lagoon was evaluated. Significantly higher cadmium (0.33 mg L(-1)) and lead (0.70 mg L(-1)) concentrations in water were observed in front of the mouth of Tigre river, whereas, zinc concentration (5.0 mg L(-1)) was significantly higher in the south part of the lagoon. Similarly, lead and zinc values in sediment (1.01 and 9.29 ?g g(-1), respectively) and oyster tissue (0.86 and 3.19 ?g g(-1), respectively) were significantly higher in the south part of the lagoon. Levels of cadmium and lead in oyster tissue were positively related to those found in sediment. However, concerning zinc no evident relationship was found. Such differences in regression analyses may be explained by differential bioaccumulation of xenobiotic (cadmium, lead) and essential (zinc) metals. PMID:21336861

Vázquez-Sauceda, María de la Luz; Aguirre-Guzmán, G; Sánchez-Martínez, J G; Pérez-Castañeda, R

2011-02-19

221

A Greenhouse Study on Lead Uptake and Antioxidant Enzyme Activities in Vetiver Grass (Vetiveria zizanioides) as a Function of Lead Concentration and Soil Physico-Chemical Properties  

NASA Astrophysics Data System (ADS)

Lead (Pb) is a toxic non-essential metal that can cause permanent learning disabilities, retardation, mental and behavioral problems in children. Lead accumulation in soils result from weathering, chipping, scraping, sanding and sand blasting of housing structures constructed prior to 1978, bearing lead-based paint. The primary objective of this study is to develop a cost-effective, chelate-assisted phytoremediation for cleaning up lead contaminated soils. Soils are a unique environment of diverse physical and chemical characteristics that influence the extent of phytoavailable (labile) Pb forms. The success of phytoremediation strategy depends on the physiological/ biochemical tolerance of the plants to lipid peroxidation induced by Pb at sub-lethal levels. Oxidative challenge is alleviated by antioxidant compounds, but more importantly by the induction of antioxidant enzymes, which are crucial for scavenging reactive oxygen species (ROS) and terminating lipid peroxidation chain reaction. A column study was conducted in a temperature and humidity-controlled greenhouse setting to assess the extent of Pb phytoextraction and antioxidant response in a lead accumulator, vetiver grass (Vetiveria zizanioides). Treatments consisted of a randomized block arrangement of 4 soil types (Immokalee, Pahokee Muck, Tobosa, and Millhopper) and 3 soil Pb concentrations [normal - 400 mg/kg lead (following federal soil standards for lead), moderate - 800 mg/kg lead, and excessive - 1200 mg/kg lead] in 4 replicates. At the end of 6 months, selected columns were amended with a biodegradable chelating agent, ethylenediamene disuccinate (10 mmol/ kg EDDS), to mobilize Pb and enhance Pb uptake by vetiver. Total and exchangeable (labile) Pb were correlated with phytoextracted Pb, and levels of antioxidant enzymes viz., superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) in the root and shoot tissues of vetiver grass. Results indicate that Pb uptake and antioxidant enzymes activity in vetiver grass is dependent on soil physico-chemical properties and phytoavailable Pb concentrations.

Andra, S. P.; Datta, R.; Sarkar, D.; Saminathan, S. K.

2006-05-01

222

Blood pressure and blood lead concentration in San Francisco MUNI bus drivers  

SciTech Connect

San Francisco MUNI bus drivers have an increased prevalence of hypertension. This study examined relationships between blood lead concentration (Pb-B) and blood pressure (BP) in 342 drivers. Two groups of subjects were identified. These subjects treated for hypertension (n = 54) and untreated subjects (n = 288). Systolic and diastolic BPs varied from 102-173 mmHg and from 61-105 mm Hg respectively in untreated subjects. They varied from 110-206 mmHg and from 73-127 mmHg respectively in treated subjects. The Pb-B varied from 2-15 {mu}g/dl in untreated subjects, and 2-25 {mu}g/dl in treated drivers. The relationship between BP and the logarithm of Pb-B was examined in each group separately using multiple regression techniques. Covariates included age, body mass index, sex, race, and caffeine intake. The regression coefficient relating systolic BP and In(Pb-B) was 1-2 mmHg/ln({mu}g/Dl) (90% C.I.: {minus}2,5) in untreated subjects. The relationship in treated subjects was too unstable to be accurately determined. The coefficients for diastolic BP were 2.0-2.5 mmHg/ln({mu}g/dl) (90% C.I.: 0.1,4.5) and 6 mmHg/ln({mu}g/dl) (90% C.I.: 2,11) in untreated and treated subjects respectively.

Sharp, D.S.

1987-01-01

223

?-Aminolevulinic acid dehydratase activity, urinary ?-aminolevulinic acid concentration and zinc protoporphyrin level among people with low level of lead exposure  

Microsoft Academic Search

To evaluate the relationship of ?-aminolevulinic acid dehydratase (ALAD) activity, urinary ?-aminolevulinic acid (ALAU) level and blood zinc protoporphyrin (ZPP) concentration to low blood lead (PbB) levels, these biomarkers were determined for all subjects enrolled from a rural area of southeast China where people had low levels of exposure to lead. The mean values of PbB, ALAD, ALAU and ZPP

Qi Wang; Huan-hu Zhao; Jian-wei Chen; Qiao-ling Hao; Kang-ding Gu; Ye-xiang Zhu; Yi-kai Zhou; Lin-xiang Ye

2010-01-01

224

The human urine metabolome.  

PubMed

Urine has long been a "favored" biofluid among metabolomics researchers. It is sterile, easy-to-obtain in large volumes, largely free from interfering proteins or lipids and chemically complex. However, this chemical complexity has also made urine a particularly difficult substrate to fully understand. As a biological waste material, urine typically contains metabolic breakdown products from a wide range of foods, drinks, drugs, environmental contaminants, endogenous waste metabolites and bacterial by-products. Many of these compounds are poorly characterized and poorly understood. In an effort to improve our understanding of this biofluid we have undertaken a comprehensive, quantitative, metabolome-wide characterization of human urine. This involved both computer-aided literature mining and comprehensive, quantitative experimental assessment/validation. The experimental portion employed NMR spectroscopy, gas chromatography mass spectrometry (GC-MS), direct flow injection mass spectrometry (DFI/LC-MS/MS), inductively coupled plasma mass spectrometry (ICP-MS) and high performance liquid chromatography (HPLC) experiments performed on multiple human urine samples. This multi-platform metabolomic analysis allowed us to identify 445 and quantify 378 unique urine metabolites or metabolite species. The different analytical platforms were able to identify (quantify) a total of: 209 (209) by NMR, 179 (85) by GC-MS, 127 (127) by DFI/LC-MS/MS, 40 (40) by ICP-MS and 10 (10) by HPLC. Our use of multiple metabolomics platforms and technologies allowed us to identify several previously unknown urine metabolites and to substantially enhance the level of metabolome coverage. It also allowed us to critically assess the relative strengths and weaknesses of different platforms or technologies. The literature review led to the identification and annotation of another 2206 urinary compounds and was used to help guide the subsequent experimental studies. An online database containing the complete set of 2651 confirmed human urine metabolite species, their structures (3079 in total), concentrations, related literature references and links to their known disease associations are freely available at http://www.urinemetabolome.ca. PMID:24023812

Bouatra, Souhaila; Aziat, Farid; Mandal, Rupasri; Guo, An Chi; Wilson, Michael R; Knox, Craig; Bjorndahl, Trent C; Krishnamurthy, Ramanarayan; Saleem, Fozia; Liu, Philip; Dame, Zerihun T; Poelzer, Jenna; Huynh, Jessica; Yallou, Faizath S; Psychogios, Nick; Dong, Edison; Bogumil, Ralf; Roehring, Cornelia; Wishart, David S

2013-09-04

225

PROSTATE-SPECIFIC ANTIGEN (PSA) IN SERUM IN RELATION TO BLOOD LEAD CONCENTRATION AND ALCOHOL CONSUMPTION IN MEN  

Microsoft Academic Search

The combined infl uence of age, smoking, alcohol, blood lead and cadmium concentrations, and serum copper, zinc, and selenium concentrations on prostate-specifi c antigen (PSA) in serum was investigated in a group of 57 men aged 21 years to 40 years. The subjects had no occupational exposure to metals and no other known reasons suspected of infl uencing prostate function

Alica PIZENT

226

An X-ray fluorescence technique for in vivo determination of lead concentration in a bone matrix  

Microsoft Academic Search

A two-component cylindrical finger phantom was constructed from silica paraffin wax and animal bone ash. The diameter of the finger bone was estimated from X-ray examinations in two orthogonal projections. The bone mineral concentration was then estimated from the quotient of the number of coherent and Compton scattered primary photons. The lead concentration in the finger bones was then derived

L. Ahlgren; S. Mattsson

1979-01-01

227

Concentrations of lead, cadmium, mercury, and copper in the crayfish ( Pacifasticus leniusculus ) obtained from a lake receiving urban runoff  

Microsoft Academic Search

Commercially caught crayfish (Pacifasticus leniusculus) were placed in a municipal lake below a combined sewer overflow outfall and a storm drain outfall associated with elevated sediment metal concentrations. Abdominal muscle, viscera, and exoskeleton from each crayfish were analyzed for mercury, cadmium, lead, and copper. Crayfish metal concentrations for each sampling site were evaluated relative to unexposed samples from the commercial

Margaret D. Stinson; David L. Eaton

1983-01-01

228

Toxicity study of lead naphthenate  

PubMed Central

van Peteghem, Th., and de Vos, H. (1974).British Journal of Industrial Medicine,31, 233-238. Toxicity study of lead naphthenate. Lead naphthenate is added to oils and greases in order to increase their resistance to high pressures. Experiments on animals and humans showed the possibility of a small amount of percutaneous absorption. An investigation was performed on technicians regularly dealing with these lubricants in order to explore to what extent they had absorbed the lead naphthenate. The degree of absorption was evaluated by measuring the lead content of the blood and the ?-aminolevulinic acid concentration in the urine. Individual results did not permit clearcut conclusions whether an increase in lead absorption had occured or not. Therefore the group of technicians was compared with a group without any occupational contact with lead-containing lubricants but otherwise comparable in occupational and general exposure to lead. To test the significance of the difference between the means of the samples a one-sided t test not assuming equal standard deviations for both populations was used. For any of two compared populations the t test was repeated after rejection of the larger values which were 2·5 standard deviations from the mean value in the exposed population. It appeared that the lead concentration in the blood and the ?-aminolevulinic acid concentration in the urine of people exposed to lead naphthenate-containing lubricants were significantly higher than those concentrations observed in non-exposed persons.

Peteghem, Th. Van; Devos, H.

1974-01-01

229

Concentration of Heavy Metals in Human Hair as a Function of an Industrial Lead Exposure.  

National Technical Information Service (NTIS)

The goal of the investigation was to find out by means of hair analyses, whether a chronically increased lead exposure of children living next to a lead-emitting industrial plant can be traced as a function of the distance of their residences to the emitt...

M. L. Spaeth

1982-01-01

230

Zinc protoporphyrin IX concentrations between normal adults and the lead-exposed workers measured by HPLC, spectrofluorometer, and hematofluorometer.  

PubMed

To establish the relationship between Zinc protoporphyrin (ZPP) concentrations and blood lead (PbB) levels and to identify reliable analytical methods of ZPP and Protoporhyrin (PP), blood samples were obtained from 263 office workers without the history of occupational lead exposure and 49 lead-acid battery workers. The mean concentrations of PbB for the normal adults and the battery workers were 9.26 microg/dl and 42.60 microg/dl, respectively. The geometric mean concentrations of ZPP and PP by HPLC were 18.73 microg/dl and 2.27 microg/dl for normal adults and were 46.99 microg/dl and 5.53 microg/dl for the exposed workers, respectively. The geometric mean concentrations of ZPP and PP by a spectrofluorometer (SF) were 30.27 microg/dl and 5.16 microg/dl for normal adults and were 50.91 microg/dl and 6.69 +/- 1.39 microg/dl for the exposed workers. The geometric mean ZPP concentration measured by a hematofluorometer (HF) was 30.88 microg/dl for normal adults. The results showed that ZPP concentrations measured by HF were consistently higher than those by HPLC and SF for normal adults, and lower for the exposed workers. ZPP concentrations were not correlated with PbB levels for normal adults but a statistically significant correlation was found among the exposed workers. PMID:11061480

Roh, Y M; Kim, K; Kim, H

2000-10-01

231

Investigations of ascorbic acid interference in urine test strips.  

PubMed

Ascorbic acid at higher concentration in urine samples can lead to false negative results in a number of urine tests, with a potential risk of clinical findings being overlooked, particularly with glucose and hemoglobin. For this reason, the ascorbic acid status of urine samples should always be routinely known so as to establish what adjustment needs to be made. A much better approach, however, is to use a test which is by design largely resistant to ascorbic acid. We compared five very common 10-parameter urine test strips from different manufacturers. The results of this study show that of the strips tested, only the product Combur-Test from Roche Diagnostics is largely resistant to ascorbic acid interference. Even lowest - but clinically relevant - concentrations of erythrocytes (10/microL), hemoglobin (0.03 mg/dL), and glucose (50 mg/dL) were correctly detected with concentrations of up to 400 mg/L ascorbic acid. Higher analyte concentrations correctly reacted positive even in the presence of up to 1000 mg/L ascorbic acid. PMID:16584061

Nagel, Dietmar; Seiler, Dieter; Hohenberger, Ewald F; Ziegler, Manfred

2006-01-01

232

Lead Concentrations in Relation to Multiple Biomarkers of Cardiovascular Disease: The Normative Aging Study  

PubMed Central

Background: Lead exposure has been associated with cardiovascular disease (CVD) in animal and human studies. However, the mechanisms of action have not been fully elucidated. We therefore examined the relationship between lead and multiple biomarkers of CVD. Methods: Participants were older men from the Normative Aging Study without preexisting coronary heart disease, diabetes, or active infection at baseline (n = 426). Serum biomarkers included lipid profile [total cholesterol, high-density lipoprotein (HDL), low-density lipoprotein (LDL), and triglycerides] and inflammatory markers [C-reactive protein, intercellular adhesion molecule-1, interleukin-6, and tumor necrosis factor receptor-2 (TNF-R2)]. We measured lead in blood and in bone by K-shell X-ray fluorescence. In this sample, 194 men (44.3%) had two or more repeated measures, resulting in 636 observations for analysis. We conducted analyses using mixed effects models with random subject intercepts. Results: Lead levels were associated with several CVD biomarkers, including levels of TNF-R2 and lipid markers. Specifically, in multivariable models, a 50% increase in blood lead level was associated with 26% increased odds of high TNF-R2 levels (> 5.52 ng/mL; odds ratio = 1.26; 95% confidence interval: 1.09, 1.45). There were positive associations of blood lead level with total cholesterol and HDL levels, and these associations were more evident when modeled as continuous outcomes than when categorized using clinically relevant cut points. In addition, longitudinal analyses indicated a significant increase in TNF-R2 levels over time to be associated with high blood lead level at the preceding visit. Conclusions: Blood lead level may be related with CVD in healthy older men through its association with TNF-R2 levels. In addition, the magnitude of the association of blood lead level with TNF-R2 level increased with age in the study population.

Peters, Junenette L.; Kubzansky, Laura D.; Ikeda, Ai; Fang, Shona C.; Sparrow, David; Weisskopf, Marc G.; Wright, Robert O.; Vokonas, Pantel; Hu, Howard; Schwartz, Joel

2011-01-01

233

Direct electrowinning of lead from suspension galena concentrate anode in different electrolytes  

NASA Astrophysics Data System (ADS)

Electrochemical extraction of lead from galena by suspension electrolysis has been examined. Galvanostatic studies with slurry electrode as well as voltametric studies with carbon paste electrode in various electrolytes have been made in order to evaluate bath performance. Sodium hydroxide has been found to result in poor dissolution whereas ionic conduction through the electrolyte as well as oxide formation at the anode hinders lead dissolution in perchlorate media. Acetate bath results in substantial amount of oxide formation at anode even though solid bed conduction dominates. Sodium chloride bath has been found to have good prospects for producing lead ions and elemental sulfur with good current efficiencies.

Paramguru, R. K.; Küzeci, E.; Kammel, R.

1988-02-01

234

Differences in trace metal concentrations (co, cu, fe, mn, zn, cd, and ni) in whole blood, plasma, and urine of obese and nonobese children.  

PubMed

High-performance ion chromatography and inductively coupled plasma-mass spectrometry methods have been applied to estimate the content of Cd, Co, Cu, Fe, Mn, Zn, and Ni in whole blood, plasma, and urine of obese and nonobese children. The study was conducted on a group of 81 Polish children of age 6-17 years (37 males, 44 females). Obese children were defined as those with body mass index (BMI) >95th percentile in each age-gender-specific group. Statistical testing was done by the use of nonparametric tests (Kruskal-Wallis's and Mann-Whitney's U) and Spearman's correlation coefficient. Significant correlations appeared for control group in plasma (Mn-Cd, Ni-Co), urine (Cu-Co), and blood (Fe-Cu), while for obese patients in plasma (Cd-Mn, Ni-Cu, Ni-Zn) and urine (Fe-Cd, Co-Mn). Sex criteria did not influence correlations between metals' content in plasma and urine of obese patients. Metals' abundance was correlated in non-corresponding combinations of body fluids. Rare significant differences between content of metals according to sex and the type of body fluids were discovered: Zn in plasma from obese patients of both sexes, and Zn, Co, and Mn in blood, Mn in plasma from healthy subjects. Negative correlations between BMI and Zn in blood, Cu in plasma, and Fe in urine were discovered for girls (control group). Positive correlation between Co content in plasma and BMI was discovered for obese boys. The changes in metals' content in body fluids may be indicators of obesity. Content of zinc, copper, and cobalt should be monitored in children with elevated BMI to avoid deficiency problems. PMID:23975578

B?a?ewicz, Anna; Klatka, Maria; Astel, Aleksander; Partyka, Ma?gorzata; Kocjan, Ryszard

2013-08-22

235

NITROGEN AND PROTEIN METABOLISM IN YOUNG PEA PLANTS AS AFFECTED BY DIFFERENT CONCENTRATIONS OF NICKEL, CADMIUM, LEAD, AND MOLYBDENUM  

Microsoft Academic Search

A comparative study was carried out on the effect of molybdenum (Mo), nickel (Ni), cadmium (Cd), and lead (Pb) using concentrations of 1×10, 1×10, and 1×10 mol dm, on the metabolism of nitrogen and proteins in young pea plants (Pisum sativum L. ‘NS Lim’). The highest concentrations of the investigated metals were noted to suppress the development of the aboveground

Slavko Kevresan; Novica Petrovic; Milan Popovic; Julijan Kandrac

2001-01-01

236

[Regional effect research of blood lead concentrations and isotopic fingerprints in four cities by ICP-MS].  

PubMed

Blood lead is a reflection of environment lead in vivo, its concentration could be used to assess lead exposure of environment quantitatively, and its isotopic ratio could be used to fingerprint environment source qualitatively. In the present study, concentrations and isotopic ratios of blood lead (BPb) of four cities in China were measured by ICP-MS for the first time. The regional effects of BPb in four Chinese cities were observed in our study. The BPb levels of industrial cities (Taiyuan and Chengdu) are higher than that of non-industrial cities (Suzhou and Beijing), indicating that industrial pollution remains primary lead contamination factor. The BPb isotopic ratios are diverse with the different character of environment the individuals live in. Food-borne lead probably has replaced the air-borne lead to be the major source of BPb in Beijing. Besides, regional effect of BPb in some developed cities is partly weakened by diversity of vast majority of imported resources. PMID:22242526

Zeng, Jing; Wang, Jing-Yu; Liu, Ya-Qiong; Xie, Qing; Ouyang, Li

2011-11-01

237

Investigation of Immobilized Enzymes for Hydrolysis of Glucuronides in Urine.  

National Technical Information Service (NTIS)

Metabolism of certain drugs leads to the formation of conjugation products with glucuronic acid prior to excretion in urine. Thus, heroin is converted to morphine, which after conjugation with glucuronic acid, appears in the urine as morphine glucuronide....

D. J. Fink M. K. Bean R. D. Falb

1975-01-01

238

Relationship between maternal sodium intake and blood lead concentration during pregnancy.  

PubMed

Pb is released from bone stores during pregnancy, which constitutes a period of increased bone resorption. A high Na intake has been found to be negatively associated with Ca and adversely associated with bone metabolism. It is possible that a high Na intake during pregnancy increases the blood Pb concentration; however, no previous study has reported on the relationship between Na intake and blood Pb concentration. We thus have investigated this relationship between Na intake and blood Pb concentrations, and examined whether this relationship differs with Ca intake in pregnant Korean women. Blood Pb concentrations were analysed in 1090 pregnant women at mid-pregnancy. Dietary intakes during mid-pregnancy were estimated by a 24 h recall method covering the use of dietary supplements. Blood Pb concentrations in whole-blood samples were analysed using graphite furnace atomic absorption spectrophotometry. Multiple regression analysis performed after adjustment for covariates revealed that maternal Na intake was positively associated with blood Pb concentration during pregnancy, but only when Ca intake was below the estimated average requirement for pregnant Korean women (P= 0·001). The findings of the present study suggest that blood Pb concentration during pregnancy could be minimised by dietary recommendations that include decreased Na and increased Ca intakes. PMID:22784671

Lee, Yo A; Hwang, Ji-Yun; Kim, Hyesook; Kim, Ki Nam; Ha, Eun-Hee; Park, Hyesook; Ha, Mina; Kim, Yangho; Hong, Yun-Chul; Chang, Namsoo

2012-07-12

239

Mercury, cadmium and lead concentrations in different ecophysiological groups of earthworms in forest soils.  

PubMed

Bioaccumulation of Hg, Cd and Pb by eight ecophysiologically distinct earthworm species was studied in 27 polluted and uncontaminated forest soils. Lowest tissue concentrations of Hg and Cd occurred in epigeic Lumbricus rubellus and highest in endogeic Octolasion cyaneum. Soils dominated by Dendrodrilus rubidus possess a high potential of risk of Pb biomagnification for secondary predators. Bioconcentration factors (soil-earthworm) followed the sequence ranked Cd>Hg>Pb. Ordination plots of redundancy analysis were used to compare HM concentrations in earthworm tissues with soil, leaf litter and root concentrations and with soil pH and CEC. Different ecological categories of earthworms are exposed to Hg, Cd and Pb in the topsoil by atmospheric deposition and accumulate them in their bodies. Species differences in HM concentrations largely reflect differences in food selectivity and niche separation. PMID:18400348

Ernst, Gregor; Zimmermann, Stefan; Christie, Peter; Frey, Beat

2008-04-09

240

ANODIC STRIPPING VOLTAMMETRY AT A MERCURY FILM ELECTRODE: BASELINE CONCENTRATIONS OF CADMIUM, LEAD, AND COPPER IN SELECTED NATURAL WATERS  

EPA Science Inventory

A simple, rapid, and inexpensive anodic stripping voltammetric method with a mercury thin film electrode is reported for the establishment of baseline concentrations of cadmium, lead, and copper in natural waters. The procedure for routine surface preparation of wax-impregnated g...

241

Concentrations of cadmium, lead and zinc in livestock feed and organs around a metal production centre in eastern Kazakhstan  

Microsoft Academic Search

This paper presents results of analysis of animal feed and meat (cattle, horse and sheep) products from a metal processing region (Oskemen) in east Kazakhstan. Samples were collected from a range of districts of differing distances from the main source of anthropogenic pollution and with differing underlying metal-containing geologies. Analyses for cadmium, lead and zinc revealed high concentrations in many

Alma A. Farmer; Andrew M. Farmer

2000-01-01

242

Organic and Inorganic Amendments Affect Soil Concentration and Accumulation of Cadmium and Lead in Wheat in Calcareous Alkaline Soils  

Microsoft Academic Search

Irrigation with untreated effluent in periurban agriculture could result in accumulation and bioconcentrations of cadmium (Cd) and lead (Pb). Different amendments were used to investigate their effect on availability, concentration, and uptake of metals by wheat in texturally different soils. Crop was irrigated with water containing Cd and Pb at 20 mg L, thereby adding 260 mg pot of each

H. R. Ahmad; A. Ghafoor; D. L. Corwin; M. A. Aziz; Saifullah; M. Sabir

2010-01-01

243

Will a doubling of atmospheric carbon dioxide concentration lead to an increase or a decrease in water consumption by crops?  

Microsoft Academic Search

Simulations with a soil\\/vegetation\\/atmosphere (SVAT) model for normal midlatitude summertime conditions were made for corn and soybeans in order to assess the effect of doubling CO2 concentration on transpiration. A second purpose of this short communication is to emphasize that feedback processes present in the plant canopy but absent in the laboratory can lead to divergence between experimental and simulated

Toby N. Carlson; James A. Bunce

1996-01-01

244

Effect of complexans (EDTA, NTA and DTPA) on the exposure to high concentrations of cadmium, copper, zinc and lead  

Microsoft Academic Search

The effects of complexans on the toxicity of short exposures to high chemical concentrations of heavy meals were examined. The heavy metals used were cadmium, zinc, lead and copper. Mortality every 24-h and the content of metal in each of three areas of fish - viscera, gills and other parts - were detemined both in the groups kept in water

S. Muramoto

1980-01-01

245

Natural lead concentrations in pristine boreal forest soils and past pollution trends: A reference for critical load models  

Microsoft Academic Search

Knowledge of natural, prepollution concentrations of heavy metals in forest soils and temporal trends of soil pollution are essential for understanding present-day pollution and for establishing realistic goals for reductions of atmospheric pollution deposition. Soils not exposed to deposition of atmospheric pollution no longer exist and, for example, present lead (Pb) pollution conditions in northern European soils are a consequence

Richard Bindler; M. L. Braennvall; Ingemar Renberg; Ove Emteryd; Harald Grip

1999-01-01

246

On-site testing of saliva and sweat with Drugwipe and determination of concentrations of drugs of abuse in saliva, plasma and urine of suspected users  

Microsoft Academic Search

Potential drug users participated voluntarily in a Belgian study on the usefulness of the non-instrumental immunoassay Drugwipe\\u000a (Securetec, Germany) for the screening of cocaine, opiates, amphetamine and cannabinoids in saliva and sweat. If one of the\\u000a screening assays (urine, oral fluid, sweat) showed a positive result, blood and saliva were collected. The on-site Drugwipe\\u000a results were correlated with the Drugwipe

N. Samyn; C. van Haeren

2000-01-01

247

Dietary Fat Subgroups, Zinc, and Vegetable Components Are Related to Urine F2a-Isoprostane Concentration, a Measure of Oxidative Stress, in Midlife Women1,2  

Microsoft Academic Search

Smoking, diet, and physical activity may impact chronic diseases in part by promoting or attenuating oxidative stress. We evaluated associations between lifestyle factors and urine F2a-isoprostanes, a marker of oxidative stress in 1610 partici- pants of the Study of Women's Health Across the Nation (SWAN). Dietary intake and physical activity were assessed at baseline and the 5th year 05 (Y05).

Kristin M. Tomey; MaryFran R. Sowers; Daniel S. McConnell; Sybil Crawford; Ellen B. Gold; John F. Randolph

248

Dietary fat subgroups, zinc, and vegetable components are related to urine F2a-isoprostane concentration, a measure of oxidative stress, in midlife women  

Microsoft Academic Search

Smoking, diet, and physical activity may impact chronic diseases in part by promoting or attenuating oxidative stress. We evaluated associations between lifestyle factors and urine F(2a)-isoprostanes, a marker of oxidative stress in 1610 participants of the Study of Women's Health Across the Nation (SWAN). Dietary intake and physical activity were assessed at baseline and the 5th year 05 (Y05). These

Kristin M. Tomey; Mary Fran R. Sowers; Xizhao Li; Daniel S. McConnell; Sybil L. Crawford; Ellen B. Gold; Bill Lasley; John F. Randolph

2007-01-01

249

Separation\\/preconcentration of trace heavy metals in urine, sediment and dialysis concentrates by coprecipitation with samarium hydroxide for atomic absorption spectrometry  

Microsoft Academic Search

Multi-element determination of trace elements in urine and dialysis solutions by atomic absorption spectrometry has been investigated. Coprecipitation with samarium hydroxide was used for preconcentration of trace elements and elimination of matrix elements. To 10 ml of each sample was added 500 ?l of 2 mgml?1 samarium solutions; the pH was then adjusted to 12.2 in order to collect trace

Sibel Saracoglu; Mustafa Soylak; Latif Elci

2003-01-01

250

Enhancing Potentially Plant-Available Lead Concentrations in Contaminated Residential Soils Using a Biodegradable Chelating Agent  

Microsoft Academic Search

Chelation of heavy metals is an important factor in enhancing metal solubility and, hence, metal availability to plants to promote phytoremediation. In the present study, we compared the effects of application of a biodegradable chelating agent, namely, ethylenediaminedisuccinic acid (EDDS) on enhancing plant available form of lead (Pb) in Pb-based paint contaminated residential soils compared to that of a more

S. Andra; R. Datta; D. Sarkar; S. Saminathan

2007-01-01

251

The concentrations, distribution and sources of cadmium, copper, lead and zinc in the atmosphere of an urban environment.  

PubMed

The four metals Cd, Cu, Pb and Zn have been measured in residential city air in a relatively small urban environment. The atmospheric concentrations are Cd, 0.516, 0.305; Cu, 12.5, 8.22; Pb, 155, 70.2; and Zn 47.4, 22.4 ng m-3 at two different sites. Except for lead the concentrations are low and more typical of rural areas in more industrialised centres. The concentrations were found to be higher in the colder and more stable air conditions existing during the winter season. Also concentrations on the flat were higher than those on a hillside probably reflecting the influence of thermal inversions. Wind direction influences the concentrations, they being greater when the wind flow comes across the industrial areas of the city. Some of the major sources of the elements are coal, soil, tyre wear and automobile emissions. PMID:8209227

Kim, N D; Fergusson, J E

1994-04-29

252

Country-specific correlations across Europe between modelled atmospheric cadmium and lead deposition and concentrations in mosses.  

PubMed

Previous analyses at the European scale have shown that cadmium and lead concentrations in mosses are primarily determined by the total deposition of these metals. Further analyses in the current study show that Spearman rank correlations between the concentration in mosses and the deposition modelled by the European Monitoring and Evaluation Programme (EMEP) are country and metal-specific. Significant positive correlations were found for about two thirds or more of the participating countries in 1990, 1995, 2000 and 2005 (except for Cd in 1990). Correlations were often not significant and sometimes negative in countries where mosses were only sampled in a relatively small number of EMEP grids. Correlations frequently improved when only data for EMEP grids with at least three moss sampling sites per grid were included. It was concluded that spatial patterns and temporal trends agree reasonably well between lead and cadmium concentrations in mosses and modelled atmospheric deposition. PMID:22459708

Harmens, H; Ilyin, I; Mills, G; Aboal, J R; Alber, R; Blum, O; Co?kun, M; De Temmerman, L; Fernández, J Á; Figueira, R; Frontasyeva, M; Godzik, B; Goltsova, N; Jeran, Z; Korzekwa, S; Kubin, E; Kvietkus, K; Leblond, S; Liiv, S; Magnússon, S H; Ma?kovská, B; Nikodemus, O; Pesch, R; Poikolainen, J; Radnovi?, D; Rühling, A; Santamaria, J M; Schröder, W; Spiric, Z; Stafilov, T; Steinnes, E; Suchara, I; Tabors, G; Thöni, L; Turcsányi, G; Yurukova, L; Zechmeister, H G

2012-03-28

253

Determination of t,t-muconic acid in urine samples using a molecular imprinted polymer combined with simultaneous ethyl chloroformate derivatization and pre-concentration by dispersive liquid-liquid microextraction.  

PubMed

The present communication describes the preparation and evaluation of a molecularly imprinted polymer (MIP) as a solid-phase extraction (SPE) sorbent and simultaneous ethyl chloroformate (ECF) derivatization and pre-concentration by dispersive liquid-liquid microextraction (DLLME) for the analysis of t,t-muconic acid (t,t-MA) in urine samples using gas chromatography-mass spectrometry. The imprinting polymer was prepared using methacrylic acid as a functional monomer, ethylene glycol dimethacrylate as a cross-linker, 2,2-azobisisobutyronitrile as the initiator and t,t-MA as a template molecule. The imprinted polymer was evaluated for its use as a SPE sorbent by comparing both imprinted and non-imprinted polymers in terms of the recovery of t,t-MA from urine samples. Molecular modelling studies were performed in order to estimate the binding energy and efficiency of the MIP complex formed between the monomer and the t,t-MA. Various factors that can affect the extraction efficiency of MIP, such as the loading, washing and eluting conditions, were optimized; other factors that can affect the derivatization and DLLME pre-concentration were also optimized. MIP in combination with ECF derivatization and DLLME pre-concentration for t,t-MA exhibits good linearity, ranging from 0.125 to 2 ?g mL(-1) (R(2) = 0.9971), with limit of detection of 0.037 ?g mL(-1) and limit of quantification of 0.109 ?g mL(-1). Intra- and inter-day precision was found to be <6%. The proposed method has been proven to be effective and sensitive for the selective pre-concentration and determination of t,t-MA in urine samples of cigarette smokers. PMID:23079953

Mudiam, Mohana Krishna Reddy; Chauhan, Abhishek; Singh, Krishna P; Gupta, Shailendra K; Jain, Rajeev; Ch, Ratnasekhar; Murthy, R C

2012-10-19

254

Relationship between lead-induced biochemical and behavioral changes with trace element concentrations in rat brain  

Microsoft Academic Search

Lead has an obvious potential to disturb learning ability, adaptive responses, and other aspects of behavior and even personality\\u000a in those who may appear healthy according to conventional medical criteria. These disturbances are shown to be associated\\u000a with alterations in ionic, cholinergic, and dopaminergic neurotransmission in the central nervous system (CNS). The present\\u000a experiment was designed to study the neurotoxic

Pardeep Sidhu; Bimla Nehru

2003-01-01

255

Direct electrowinning of lead from suspension galena concentrate anode in different electrolytes  

Microsoft Academic Search

Electrochemical extraction of lead from galena by suspension electrolysis has been examined. Galvanostatic studies with slurry\\u000a electrode as well as voltametric studies with carbon paste electrode in various electrolytes have been made in order to evaluate\\u000a bath performance. Sodium hydroxide has been found to result in poor dissolution whereas ionic conduction through the electrolyte\\u000a as well as oxide formation at

R. K. Paramguru; E. Küzeci; R. Kammel

1988-01-01

256

Copper and lead concentrations in salt marsh plants on the Suir Estuary, Ireland  

Microsoft Academic Search

Concentrations of Cu and Pb were determined in the roots and shoots of six salt marsh plant species, and in sediment taken from between the roots of the plants, sampled from the lower salt marsh zone at four sites along the Suir Estuary in autumn 1997. Cu was mainly accumulated in the roots of monocotyledonous and dicotyledonous species. Pb was

E. J Fitzgerald; J. M Caffrey; S. T Nesaratnam; P McLoughlin

2003-01-01

257

Concentration of cadmium, copper, lead, and zinc in six species of freshwater clams  

Microsoft Academic Search

Reports of the occurrence and accumulation of heavy metals in pelecypods have generally been limited to salt water forms (AYLING, 1974; iRELAND, 1973; KOPFLER and MAYER, 1973; PENTREATH, 1973; VALIELA and BANUS, 1974; WINDOM and SMITH, 1972). This is apparently due to the concern over contamination of commercial oyster and mussel beds. Few reports of heavy metal concentrations in freshwater

Richard V. Anderson

1977-01-01

258

Trace metal concentrations and lead isotopic composition in surface waters of the Northeast Pacific along the United States - Mexico boundary  

SciTech Connect

To evaluate the magnitude of heavy metal contamination along the United States - Mexico boundary, trace metal concentrations (Pb, Cd, Mn, Fe, and Zn) and lead isotopic composition ([sup 204]Pb, [sup 206]Pb, [sup 207]Pb, and [sup 208]Pb) were measured along four surface water transects across the continental shelf off the Baja California Coast. The stations were located between 2 to 45 km offshore, including both coastal and open ocean locations. All the metal distributions along the transects were characterized by offshore concentration gradients. The highest trace metal concentrations occurred in coastal waters in association with high salinities and nutrient concentrations. There was also a longshore gradient in trace metal concentrations. Trace element concentrations were lower in the southern locations than along the United States - Mexico boundary, and were comparable to typical open ocean values. The relative enrichment of metals in surface waters off the northern part of Baja California was primarily associated with advection/upwelling processes, not with anthropogenic inputs. Mass balance calculations indicated that about 1% of Cd and 13% of Zn were from urban discharges. The low metal levels measured in coastal waters off the central part of Baja California were attributed to the intrusion of open ocean waters, based on hydrographic data, satellite images and lead isotopic compositions.

Sanudo-Wilhelmy, S. (Inst. of Marine Science, Santa Cruz, CA (United States))

1990-01-09

259

Effects of pH and carbonate concentration on dissolution rates of the lead corrosion product PbO(2).  

PubMed

Lead(IV) oxide is a corrosion product that can develop on lead pipes and affect lead concentrations in drinking water. Continuously stirred flow-though reactors were used to quantify the dissolution rates of plattnerite (beta-PbO(2)) at different pH values and dissolved inorganic carbon (DIC) concentrations. Organic pH buffers were not used, because several were found to be reductants for PbO(2) that accelerated its dissolution. Most plattnerite dissolution rates were on the order of 10(-10) mol/min-m(2). The rate of dissolution increased with decreasing pH and with increasing DIC. The effect of DIC is consistent with a reductive dissolution mechanism that involves the reduction of Pb(IV) to Pb(II) at the plattnerite surface followed by the formation of soluble Pb(II)-carbonate complexes that accelerate Pb(II) release from the surface. Under the experimental conditions, dissolved lead concentrations were controlled by the dissolution rate of plattnerite and not by its equilibrium solubility. A dissolution rate model was developed and can be used to predict dissolution rates of plattnerite as a function of pH and DIC. PMID:20063875

Xie, Yanjiao; Wang, Yin; Singhal, Vidhi; Giammar, Daniel E

2010-02-01

260

Measurement of Fuel Concentration Profile at Leading Edge of Lifted Flame with Acetone Laser-Induced Fluorescence  

NASA Astrophysics Data System (ADS)

This is a study of the leading-edge characteristics of a methane-air triple flame. Few experiment results are available for physical examination of such characteristics, so further experimental investigations are strongly needed to understand the stability mechanism in a mixture with a steep concentration gradient. To this end, we measured concentration profiles at the leading edge of a flame using acetone laser-induced fluorescence (acetone LIF). The results demonstrated that the lifted height of the flame changed when acetone was added to the mixture and correlated well with increased C2 radical behind the flame edge. However, the OH radical luminous intensity, measured with a spectroscope, did not change with addition of acetone. Moreover, the burning velocity obtained by the Bunsen-burner method remained constant when acetone was added to the mixture. Therefore, acetone had little influence on burning intensity. Acetone LIF can thus be employed to measure the local concentration gradient at the leading edge of a flame. The acetone LIF signals could be corrected to consider the thermal effect by using silicone oil vanishing-plane data. From the corrected acetone LIF data, the width between the lean and rich flammability limits (flammability limit width) in the flow upstream of the flame with a steep concentration gradient was clearly observed and could be quantitatively compared with the recent numerical results.

Hirota, Mitsutomo; Sekine, Kazushi; Hashimoto, Kouta; Saiki, Atsushi; Takahashi, Hidemi; Masuya, Goro

261

Root growth of Cynodon dactylon and Eleusine indica collected from motorways at different concentrations of lead  

SciTech Connect

An ecological survey was conducted on the roadside vegetation at three different sites: Tai Po, a commercial and residential area (average annual daily traffic (AADT) = 23730; and Shek O and Wu Kai Sha, recreational areas (AADT = 1590 and 20, respectively). Cynodon dactylon and Eleusine indica were the two most dominant species recorded. The Tai Po site had higher Pb contents in both soil and plant, followed by Shek O, and then Wu Kai Sha. Tillers of C. dactylon and E. indica from the three sites were subjected to a series concentrations of Pb(NO/sub 3/)/sub 2/. By comparing their indexes of tolerance and values of 14-day EC/sub 50/ (effective concentration reducing the normal root growth by 50%), roadside populations of the two grasses collected from Tai Po and Shek O, especially the former one, were more tolerant to elevated levels of Pb compared with those collected from Wu Kai Sha.

Wong, M.H.; Lau, W.M.

1985-04-01

262

A micro-extractor for concentration and determination of lead in water  

Microsoft Academic Search

In this work, we present the design, fabrication and characterization of a novel micro-extractor that performs on-line extraction–concentration–detection (ECD) of target molecules flowing in a carrier liquid. The system comprises a primary microchannel containing a flowing aqueous carrier liquid and a secondary organic storage fluid circulating in an adjacent channel. The interfaces between the two immiscible fluids are stabilized by

Tran Van Man; Jean Berthier; Patrick Ozil; Nicolas Sarrut

2011-01-01

263

Preconditioning with adenosine leads to concentration-dependent infarct size reduction in the isolated rabbit heart  

Microsoft Academic Search

Adenosine (ADO) has a cardioprotective effect in ischemia-reperfusion injury when administered both prior to ischemia and during reperfusion. ADO has also been implicated in the mechanism of ischemic pre-conditioning. The aim of this study was to investigate whether there was a concentration-response between the administration of ADO prior to ischemia-reperfusion and reduction in subsequent infarct size. Rabbit isolated perfused hearts

R. G. Woolfson; V. C. Patel; D. M. Yellon

1996-01-01

264

The effect of low gold concentrations on the creep of eutectic tin-lead joints  

NASA Astrophysics Data System (ADS)

The effects of low Au concentrations on the creep properties of a eutectic Sn/Pb alloy were investigated. Creep testing was performed on double-shear specimens of fine-grained, eutectic Sn/Pb joints with Au concentrations of 0, 0.2, 1.0, and 1.5 wt pct Au at 90 °C, 0, 0.2, and 1.0 wt pct Au at 65°C, and 0.2 wt pct Au at 25 °C. In the absence of Au, the creep of finegrained eutectic Sn/Pb is dominated by grain-boundary sliding at high homologous temperature and intermediate stress. The addition of 0.2 wt pct Au or more suppressed this mechanism; the high-stress, bulk-creep mechanism was dominant at all stresses tested. Higher concentrations of Au increased porosity within the joints. The porosity decreased joint strength. During failure, the crack path followed softer regions of the joint; cracks propagated through Pb-rich islands or along Sn/Sn grain boundaries.

Kramer, P. A.; Glazer, J.; Morris, J. W.

1994-06-01

265

Events leading to cell death and lysis of Neisseria meningitidis in low concentrations of penicillin G.  

PubMed

Neisseria meningitidis SD1C exhibited a low tolerance to penicillin G (0.03 microgram/ml). Loss of viability in the absence of polyvinylpyrrolidone-40 and horse serum was independent of the concentration of antibiotic above the minimum inhibitory concentration, whereas the rate of bacteriolysis was concentration dependent. Penicillin-induced lysis was a secondary event in this organism. At low levels of penicillin G, growth characteristics, i.e., absorbancy changes, respiratory rate, and uptake of Mg2+, appeared normal during the first 90 min in penicillin; however, viability dropped dramatically. Additionally, total cell numbers remained constant while cell mass continued to increase at a rate normal for the population. The increase in cellular mass in the absence of cell division could be observed microscopically. Only one ultrastructural change induced by penicillin correlated with the loss in viability: the loss in continuity of the outer membrane with the peptidoglycan but only at the site of septum formation. This lesion did not occur when cells were grown in media supplemented with the protective agents polyvinylpyrrolidone-40 and horse serum. Under these conditions of growth and with relatively high levels of penicillin, constant viability was maintained, but cell division no longer occurred. Cell populations treated with penicillin in the presence of the protective agents became increasingly more dependent on the presence of these agents for total viability even in the absence of penicillin in the culture. PMID:6772094

Neirinck, L G; DeVoe, I W; Ingram, J M

1980-04-01

266

GerES IV: phthalate metabolites and bisphenol A in urine of German children.  

PubMed

Urine samples from GerES IV were analysed for concentrations of the metabolites of DEHP (MEHP, 5OH-MEHP, 5oxo-MEHP, 5cx-MEPP, and 2cx-MMHP), DnBP and DiBP (MnBP and MiBP), BBzP (MBzP), DiNP (7OH-MMeOP, 7oxo-MMeOP and 7cx-MMeHP), and bisphenol A (BPA) to assess the exposure of German children on a representative basis. 600 morning urine samples had been randomly chosen from stored 1800 GerES IV samples originating from 3 to 14 year old children living in Germany. All metabolites could be detected in nearly all urine samples (N=599). Descriptive data analysis leads to mean concentrations of 5-OH-MEHP and 5-oxo-MEHP of 48microg/l and 37microg/l, respectively. The mean concentration of 7OH-MMeOP was 11microg/l. MnBP, MiNP, MBzP showed mean levels of 96microg/l, 94microg/l, and 18microg/l, respectively. The concentrations of the phthalate metabolites decreased with increasing age. Compared to German adults all children showed three to five fold higher urine concentrations than adults analysed in the same decade. For some children the levels of the sum of 5OH-MEHP and 5oxo-MEHP in urine were higher than the German human biomonitoring value (HBM I) of 500mcirog/l, which indicates that adverse health effects cannot be excluded for these subjects with sufficient certainty. The mean concentration of BPA in urine was 2.7microg/l. A rough calculation of the daily intakes on the basis of the measured concentrations in urine resulted in daily intakes two orders of magnitude lower than the current EFSA reference dose of 50microg/kgbw/d. PMID:19729343

Becker, Kerstin; Göen, Thomas; Seiwert, Margarete; Conrad, Andre; Pick-Fuss, Helga; Müller, Johannes; Wittassek, Matthias; Schulz, Christine; Kolossa-Gehring, Marike

2009-09-02

267

Comparison of Nevirapine Plasma Concentrations between Lead-In and Steady-State Periods in Chinese HIV-Infected Patients  

PubMed Central

Objectives To investigate the potential of nevirapine 200 mg once-daily regimen and evaluate the influence of patient characteristics on nevirapine concentrations. Methods This was a prospective, multicentre cohort study with 532 HIV-infected patients receiving nevirapine as a part of their initial antiretroviral therapy. Plasma samples were collected at trough or peak time at the end of week 2 (lead-in period) and week 4, 12, 24, 36, and 48 (steady-state period), and nevirapine concentrations were determined using a validated HPLC method. Potential influencing factors associated with nevirapine concentrations were evaluated using univariate and multivariate logistic regression. Results A total of 2348 nevirapine plasma concentrations were collected, including 1510 trough and 838 peak values. The median nevirapine trough and peak concentration during the lead-in period were 4.26 µg/mL (IQR 3.05–5.61) and 5.07 µg/mL (IQR 3.92–6.44) respectively, which both exceeded the recommended thresholds of nevirapine plasma concentrations. Baseline hepatic function had a moderate effect on median nevirapine trough concentrations at week 2 (4.25 µg/mL v.s. 4.86 µg/mL, for ALT <1.5×ULN and ?1.5×ULN, respectively, P?=?0.045). No significant difference was observed in median nevirapine trough concentration between lead-in and steady-state periods in patients with baseline ALT and AST level ?1.5×ULN (P?=?0.171, P?=?0.769), which was different from the patients with ALT/AST level <1.5ULN. The median trough concentrations were significantly higher in HIV/HCV co-infected patients than those without HCV at week 48 (8.16 µg/mL v.s. 6.15 µg/mL, P?=?0.004). Conclusions The 200 mg once-daily regimen of nevirapine might be comparable to twice-daily in plasma pharmacokinetics in Chinese population. Hepatic function prior to nevirapine treatment and HIV/HCV coinfection were significantly associated with nevirapine concentrations. Registration Clinicaltrial.gov ID: NCT00872417

Li, Yanling; Xie, Jing; Qiu, Zhifeng; Ye, Min; Fu, Qiang; Han, Yang; Zhu, Zhu; Li, Taisheng

2013-01-01

268

Odors from evaporation of acidified pig urine  

Microsoft Academic Search

In the Dutch Hercules project feces and urine from pigs are collected separately underneath the slatted floor in a pig house and treated in two processes. Feces are composted and urine is concentrated by water evaporation in a packed bed. Exhaust air from the pig house is used for the evaporation in a packed bed scrubber. Before entering the scrubber,

H. C. Willers; P. J. Hobbs; N. W. M. Ogink

2004-01-01

269

Effect of substrate concentration, soil moisture, and organic materials on urease activity of soil contaminated with lead  

Microsoft Academic Search

A laboratory experiment was carried out in order to study the effect of substrate concentration, soil moisture, and type of organic materials on urease activity of soils containing variable lead (Pb) contents. Various Pb levels ranging from 52.1 – 589.9 mg kg were created by mixing uncontaminated (containing 52.1 mg Pb kg soil) and contaminated (containing 589.9 mg Pb kg soil) soils in different proportions.

R. S. Antil; M. K. Mahata; R. P. Narwal

2006-01-01

270

Cadmium, lead, calcium, magnesium, copper, and zinc concentrations in human infant tissues: their relationship to Sudden Infant Death Syndrome  

SciTech Connect

The purpose of this study was to determine whether there was any evidence of an excess of the toxic elements, cadmium and lead, or a deficiency of any of the essential elements, calcium, magnesium, copper, and zinc, in the tissues of infants who died of Sudden Infant Death Syndrome (SIDS) as compared to those of infants who died of other causes. The literature was reviewed for SIDS, mineral metabolism, and mineral interactions. Lung, liver, kidney, and rib specimens were obtained at autopsy from 130 infants who died suddenly and unexpectedly. There were 85 SIDS cases ranging in age from 2 to 64 weeks and 45, aged 1 to 92 weeks, who died of other causes. Concentrations of cadmium, lead, calcium, magnesium, copper, and zinc in each tissue were determined by electrothermal and flame atomic absorption spectrophotometry. Statistical analysis of the data showed that liver and rib lead concentrations and liver magnesium concentrations were significantly higher in SIDS tissues in the 4 to 26 week age group than in non-SIDS tissues in the same age group. There was no evidence of a deficiency of the essential minerals measured.

Erickson, M.M.

1981-01-01

271

Slow, steady discharge regime for concentrated lead-acid cells with planar, cylindrical, and spherical electrodes  

NASA Astrophysics Data System (ADS)

A recent theoretical study of slow, steady discharge for a lead-acid cell carrying current I, with planar electrodes, predicts a nonzero bulk charge distribution with an associated voltage profile within the electrolyte that is quadratic in space. A second theoretical study finds that the Ohmic voltage resistance R=?V/I across the electrolyte differs from the Joule heating resistance RJ=P/I2. The very different diffusion constants of the charge-carrying ions H+ and HSO4- is responsible for the quadratic voltage profile. The presence of changing chemical energies is responsible for the different resistances. In the present work we study this same chemical system for the cylindrical and spherical geometries, with Pb at inner radius a and PbO2 at outer radius b. For the cylindrical case, the voltage varies with radius as the sum of a logarithm and a quadratic. For the spherical case, the voltage varies with the radius as a sum of an inverse r and a quadratic. For both cases, the quadratic is the signature of a uniform nonzero bulk charge distribution. For both cases, R?RJ. For large enough b/a, in both the spherical and cylindrical cases, we find that R<0 current flows from lower to higher electrical potential. This does not violate energy conservation when chemical as well as electrical energies are included.

Yang, Yigang; Saslow, Wayne M.

1998-12-01

272

Use of a gonadotropin-releasing hormone agonist during ovarian stimulation leads to significant concentrations of peptide in follicular fluids.  

PubMed

The penetration of a gonadotropin-releasing hormone agonist (GnRH-a), Buserelin (Hoechst AG, Frankfurt, West Germany), into human follicular fluids (FF) was studied by means of a radioimmunoassay (RIA) and a bioassay. Acute nasal administration of a therapeutic dose of Buserelin (300 and 600 micrograms) before the ovum pickup for in vitro fertilization leads to significant concentrations of Buserelin in one-third of the FF. These concentrations ranged between 28 and 124 pg/ml, which represents 10% to 50% of the serum concentrations achieved in these patients. Follicular penetration of this agonist is time-dependent. Chronic administration during the follicular phase leads to low but significant concentrations of peptide 36 hours after the last inhalation. A very good correlation was observed between the RIA and the bioassay. This demonstrates the accuracy and the specificity of the RIA. In addition, it indicates that the Buserelin that reaches follicles is intact and is not the inactive product of degradation. Intranasal administration of Buserelin stopped 35 hours before ovum pickup appears to be an adequate way of minimizing the exposure of maturing oocytes to the GnRH-a. PMID:2502440

Loumaye, E; Coen, G; Pampfer, S; Vankrieken, L; Thomas, K

1989-08-01

273

No relationship found between mercury and lead concentrations in muscle and scales of chub Squalius cephalus L.  

PubMed

We examined the relationship between muscle and scale mercury (Hg) and lead (Pb) concentrations in chub Squalius cephalus L. from six riverine sites in the Czech Republic in order to determine whether scale analysis alone could provide a nonlethal and convenient method for prediction of heavy metal concentration in muscle tissue. Our results confirm tissue-specific heavy metal accumulation in chub, with Hg tending to accumulate primarily in muscle tissue and Pb in scales. We found no significant relationship, however, for concentrations of either Pb or Hg between muscle tissue and scales of chub. Our results indicate that scales cannot be used for predicting heavy metal contamination in muscle of chub and we recommend, therefore, that muscle biopsy methods continue as the preferred method of analysis. PMID:22864581

Valová, Zdenka; Hudcová, Hana; Roche, Kevin; Svobodová, Jana; Bernardová, Ilja; Jurajda, Pavel

2012-08-03

274

When are fetuses and young children most susceptible to soil metal concentrations of arsenic, lead and mercury?  

PubMed Central

This study was designed to analyze when, during pregnancy and early childhood, the association between soil metal concentrations of arsenic (As), lead (Pb) and mercury (Hg) and the outcome of intellectual disability (ID) is statistically significant. Using cluster analysis, we identified ten areas of land that contained a cluster of ID and areas of average risk for ID. We analyzed soil for As, Pb, and Hg and estimated the soil metal concentration at the residential sites where the woman and children lived during pregnancy and early childhood using a Bayesian Kriging model. Arsenic concentrations were associated with ID during the first trimester of pregnancy and Hg was associated with ID early in pregnancy and the first two years of childhood. The covariates that remained in the final models were also temporally associated with ID.

McDermott, Suzanne; Bao, Weichao; Aelion, C. Marjorie; Cai, Bo; Lawson, Andrew

2012-01-01

275

Urine pH  

MedlinePLUS

... Drugs that can decrease urine pH include ammonium chloride, thiazide diuretics, and methenamine mandelate. Eat a normal, ... is associated with xanthine, cystine, uric acid , and calcium oxalate stones. Alkaline urine is associated with calcium ...

276

Lead, zinc, and chromium concentrations in acidic headwater streams in Sweden explained by chemical, climatic, and land-use variations  

NASA Astrophysics Data System (ADS)

Long-term data series (1996-2009) for eleven acidic headwater streams (< 10 km2) in Sweden were analyzed to determine factors controlling concentrations of trace metals. In-stream chemical data as well climatic, flow, and deposition chemistry data were used to develop models predicting concentrations of chromium (Cr), lead (Pb), and zinc (Zn). Data were initially analyzed using partial least squares to determine a set of variables that could predict metal concentrations across all sites. Organic matter (as absorbance) and iron related positively to Pb and Cr, while pH related negatively to Pb and Zn. Other variables such as conductivity, manganese, and temperature were important as well. Multiple linear regression was then used to determine minimally adequate prediction models which explained an average of 35% (Cr), 52% (Zn), and 72% (Pb) of metal variation across all sites. While models explained at least 50% of variation in the majority of sites for Pb (10) and Zn (8), only three sites met this criterion for Cr. Investigation of variation between site models for each metal revealed geographical (altitude), chemical (sulfate), and land-use (silvaculture) influences on predictive power of the models. Residual analysis revealed seasonal differences in the ability of the models to predict metal concentrations as well. Expected future changes in model variables were applied and results showed the potential for long-term increases (Pb) or decreases (Zn) for trace metal concentrations at these sites.

Huser, B. J.; Fölster, J.; Köhler, S. J.

2012-11-01

277

Trichloroethylene exposure. Biological monitoring by breath and urine analyses.  

PubMed Central

A mathematical model developed previously has been used to study some aspects of biological monitoring of exposure to trichloroethylene (TRI) by the analysis of this solvent in alveolar air or of its metabolites, trichloroethanol (TCE) and trichloroacetic acid (TCA), in urine. Assuming that a biological control must be representative of the time-weighted average concentration (TWA), it was found that sampling for TRI and TCE analyses must be carried out the morning after the exposure being considered. On the other hand, for a TCA analysis, the timing of urine sampling is not a determinant factor. Theortical limit concentrations have been set up for these biological indicators, but it is shown that their application must be restricted to exposures which are quantitatively reproducible from one day to the next. In all other cases, it appears that this monitoring method can lead to errors in the estimated exposure concentrations. A tentative method of biological monitoring is therefore proposed. It is based on the analysis of TCE in the urine or TRI in the alveolar air before and after the exposure being monitored. TCA is not considered to be sensitive enough to variations in the inspired concentration to be used as an indicator of a single exposure risk.

Droz, P O; Fernandez, J G

1978-01-01

278

Biological reference materials for assaying human albumin in urine  

Microsoft Academic Search

To assess the interlaboratory variation in the results of albumin measurements, we prepared albumin solutions in human urine at various concentrations within the normal range. Since some investigators have reported that albumin is unstable in some human urine samples stored at -20°C, we screened urine samples from 21 persons to identify samples that were stable under these conditions and that

Patricia W. Mueller; Mary Louise MacNeil; Karen K. Steinberg

1990-01-01

279

Thermal lens study of thermo-optical properties and concentration quenching of Er3+-doped lead pyrophosphate based glasses  

SciTech Connect

In this work, we have used the thermal lens technique combined with conventional spectroscopy to characterize the thermo-optical properties of Er3+-doped lead pyrophosphate-based glasses. More precisely, we have investigated and quantified experimentally the fluorescence quantum efficiencies of the Er3+ levels, and we describe the role of concentration quenching effects. The fluorescence quantum efficiency of the 4I13/2 level is very high when compared to other phosphate glasses, while that of the green-coupled levels is very small. Other important photonic materials parameters, such as the thermal diffusivity and temperature coefficient of the optical path length change, were obtained and compared with those of other glass systems. The cumulative results obtained here for the Er-doped lead pyrophosphate glass show that this material is a good candidate for photonic applications with a characteristic Er3+ infrared emission around 1550 nm.

Santos, C. C. [Universidade Federal do Ceara, Ceara, Brazil; Rocha, U. [Grupo de Fotônica e Fluidos Complexos, Instituto de Física, Brazil; Guedes, Ilde [Universidade Federal do Ceara, Ceara, Brazil; Vermelho, M. V. D. [Instituto de Fisica, Universidade Federal de Alagoas, Brazil; Boatner, Lynn A [ORNL; Jacinto, C. [Instituto de Fisica, Universidade Federal de Alagoas, Brazil

2012-01-01

280

Spot Urine Osmolality\\/Creatinine Ratio in Healthy Humans  

Microsoft Academic Search

Background: Spot urine albumin\\/creatinine ratio is a reliable estimate of 24-hour urine albumin excretion. In a pilot study, we observed that the spot urine osmolality\\/creatinine ratio (Uosm\\/Ucr) in healthy adults is reproducible. Therefore, we postulated that Uosm\\/Ucr of a spot urine sample may give an overall estimate of urinary excretion of solutes, renal concentrating ability and body hydration status. Method:

Srini Godevithanage; Piyumi P. Kanankearachchi; Mahanama P. Dissanayake; Thilak A. Jayalath; Nimal Chandrasiri; Rangani P. Jinasena; Ranjith P. V. Kumarasiri; Chulananda D. A. Goonasekera

2010-01-01

281

Evidence of the particle concentration effect for lead and other metals in fresh waters based on ultraclean technique analyses  

NASA Astrophysics Data System (ADS)

Ultraclean methods were used to produce reliable concentration data for the trace metals Pb, Ag, and Cd in fresh waters and for Ph, Ag, Cu, and Zn in estuarine waters. Partitioning of metals between filter-retained and filtrate fractions exhibited a dependence on total suspended solids (TSS) concentration. This phenomenon, the particle concentration effect (PCE), has been previously documented almost exclusively in marine and estuarine systems and lab simulations, and mainly for radionuclides. The partition coefficient, Kd, was independent of major ion chemistry and pH, supporting the hypothesis that the PCE is caused by metals associated with colloidal particles but counted with the filtrate ("dissolved") fraction. Partition coefficients of the measured metals in fresh waters are predictable across the full range of TSS measured, spanning more than two orders of magnitude. The inferred true partition coefficient for Pb (between solution and particles of all size classes) is greater than 107.4, suggesting that truly dissolved Pb concentrations are extraordinarily low. Previously published data are reinterpreted to show that naturally occurring 210Pb also exhibits the PCE. Freshly precipitated Fe oxyhydroxides partition metals exactly like organic detritus and clays in spite of the great difference in their surface chemistry. The same data rule out the possibility that the PCE could be caused by a decrease in surface area (and surface complexation sites) due to resuspension of larger particles under high TSS conditions. A surprising result is that, while the slope of a log (Kd) - log (TSS) plot for 210Pb is the same as for stable lead, absolute Kd values for 210Pb are uniformly lower by a factor of 4. This suggests that 210Pb and stable lead behave differently from each other in the surface waters studied. One possible explanation is that this dissimilarity may be attributable to differences in speciation that are persistent on a time scale of months, corresponding to the water residence time or Pb removal rate.

Benoit, Gaboury

1995-07-01

282

Effect of pH on the concentrations of lead and trace contaminants in drinking water: a combined batch, pipe loop and sentinel home study.  

PubMed

High lead levels in drinking water are still a concern for households serviced by lead pipes in many parts of North America and Europe. This contribution focuses on the effect of pH on lead concentrations in drinking water delivered through lead pipes. Though this has been addressed in the past, we have conducted a combined batch, pipe loop and sentinel study aiming at filling some of the gaps present in the literature. Exhumed lead pipes and water quality data from the City of London's water distribution system were used in this study. As expected, the lead solubility of corrosion scale generally decreased as pH increased; whereas dissolution of other accumulated metals present in the corrosion scale followed a variety of trends. Moreover, dissolved arsenic and aluminum concentrations showed a strong correlation, indicating that the aluminosilicate phase present in the scale accumulates arsenic. A significant fraction of the total lead concentration in water was traced to particulate lead. Our results indicate that particulate lead is the primary contributor to total lead concentration in flowing systems, whereas particulate lead contribution to total lead concentrations for stagnated systems becomes significant only at high water pH values. PMID:21458838

Kim, Eun Jung; Herrera, Jose E; Huggins, Dan; Braam, John; Koshowski, Scott

2011-03-11

283

Family with intermittent maple syrup urine disease  

PubMed Central

A family is described in which the 3 children presented with episodes of severe metabolic acidosis secondary to minor infections. 2 of them died, and 1 of these was severely retarded. The sole surviving child is 6 years old and is normal with respect to physical and mental development. Gas chromatography of the urine obtained during episodes of ketoacidosis showed the keto and hydroxy acids characteristic of maple syrup urine disease, and thin layer chromatography of the plasma and urine showed greatly increased concentrations of the branched chain amino acids. The urine and plasma of the surviving child was chromatographically normal between episodes. The leucocyte branched chain keto acid decarboxylase activity in this patient and her father was reduced. The range of features in this family with intermittent maple syrup urine disease illustrates the necessity for prompt and careful investigation of metabolic acidosis of unknown aetiology.

Valman, H. B.; Patrick, A. D.; Seakins, J. W. T.; Platt, J. W.; Gompertz, D.

1973-01-01

284

Surveillance of workers exposed to mercury vapor:validation of a previously proposed biological threshold limit value for mercury concentration in urine  

SciTech Connect

A cross-sectional epidemiological study was carried out among subjects exposed to mercury (Hg) vapor, ie, a group of 131 male workers (mean age: 30.9 yr; average duration of exposure, 4.8 yr) and a group of 54 female workers (mean age, 29.9 yr; average duration of exposure 7 yr). The results were compared with those obtained in well-matched control groups comprising 114 and 48 male and female workers, respectively. The intensity of current Hg vapor exposure was rather moderate as reflected by the levels of mercury in urine (HgU) (mean and 95th percentile: males 52 and 147 micrograms/g creatinine; females 37 and 63 micrograms/g creatinine) and of mercury in blood (mean and 95th percentile: males 1.4 and 3.7 micrograms/dl; females 0.9 and 1.4 microgram/dl). Several symptoms mainly related to the central nervous system (memory disturbances, depressive feelings, fatigue, irritability) were more prevalent in the Hg-exposed subjects. They were, however, not related to exposure parameters. In both male and female Hg-exposed workers no significant disturbances were found in short-term memory (audioverbal), simple reaction time (visual), critical flicker fusion, and color discrimination ability. Only slight renal tubular effects were detected in Hg-exposed males and females, ie, an increased urinary beta-galactosidase activity and an increased urinary excretion of retinol-binding protein. The prevalence of these preclinical renal effects was more related to the current exposure intensity (HgU) than to the duration of exposure and was detected mainly when HgU exceeds 50 micrograms/g creatinine. Changes in hand tremor spectrum recorded with an accelerometer were found in the Hg-exposed males only.

Roels, H.; Gennart, J.P.; Lauwerys, R.; Buchet, J.P.; Malchaire, J.; Bernard, A.

1985-01-01

285

Serum and urine ionic fluoride  

Microsoft Academic Search

The present study was undertaken to evaluate the fluoride status in the general healthy population of Barcelona. Serum and\\u000a urine fluoride ionic concentration was determined in a random sample of 250 subjects (age range 15–90 yr) by the Orion fluoride\\u000a electrode system to determine the normal range of fluoride in this population. The results obtained show that in the general

M. Torra; M. Rodamilans; J. Corbella

1998-01-01

286

Urine Adulteration in Drug Testing  

Microsoft Academic Search

Drug abusers may attempt to conceal their drug intake by interfering with the clinical specimens sent to the laboratory for toxicology screening. This report describes a 27-year-old drug abuser who repeatedly submitted urine samples with abnormally low creatinine concentrations in order to invalidate drug screening. Adulteration by addition of ammonia-containing cleanser was sus- pected and eventually admitted by the patient.

CWK Lam

2005-01-01

287

[Urine conservation by surface-active agents].  

PubMed

The antibacterial activity of surface-active substances -- catamine-AB, catapine B-300, GIPH-200 and Tego-51 was measured on the E. coli and Staphylococcus aureus cultures and anthracoid spores. The purpose of the measurements was to explore the use of the substances as urine conserving agents. Catamine-AB showed the highest antibacterial activity. Anthracoid spores exhibited the highest resistance to the substances; staphylococci were less resistant than E. coli. Investigations of the effectiveness of urine conservation demonstrated that catamine-AB at a concentration of 0.1% killed all Staph. aureus and E. coli. Therefore, it can be recommended as a urine conserving agent. PMID:2807

Prishchep, A G; Borshchenko, V V; Zarubina, K V

288

Widening the problem of lead poisoning to a South-American top scavenger: Lead concentrations in feathers of wild Andean condors  

Microsoft Academic Search

Lead poisoning is not a new threat for wild birds, but it is now playing an important role in shaping raptor populations. Studies have been focused mainly on Europe, North-America, and Japan, but little is known about the situation in South-America. Lead is a serious threat for wildlife, especially for long-lived species. Nevertheless, no information is available for wild Andean

Sergio A. Lambertucci; José Antonio Donázar; Antonio Delgado Huertas; Begoña Jiménez; Mónica Sáez; José Antonio Sanchez-Zapata; Fernando Hiraldo

2011-01-01

289

Determination of lead concentrations and isotope ratios in recent snow samples from high alpine sites with a double focusing ICP-MS  

Microsoft Academic Search

A double focusing ICP-MS, equipped with a Micro Concentric Nebulizer, has been used to determine concentrations and isotopic\\u000a ratios of lead in recent snow samples (1993–1996) from high alpine sites in Switzerland. Concentrations varied between 0.02\\u000a ± 0.002 and 5.5 ± 0.15 ng\\/g and are slightly lower than concentrations reported by Atteia [1], by Batifol et al. [2], and\\u000a by

T. Döring; M. Schwikowski; H. W. Gäggeler

1997-01-01

290

Uranium in Urine  

Microsoft Academic Search

DURING some work in this Research Department on compounds of uranium, as a safety precaution, we commenced to analyse the urine of personnel concerned, using a fluorimetric method. In the preparation of fluorimetric standards, known amounts of uranyl nitrate were added to samples of urine from persons not engaged on the work with uranium. To our surprise we found uranium

H. M. Wilson; A. A. Smales

1946-01-01

291

Urine Tests (For Parents)  

MedlinePLUS

... number and variety of red and white blood cells the presence of bacteria or other organisms the presence of substances, such as glucose, that usually shouldn't be found in the urine the pH, which shows how acidic or basic the urine ...

292

Papain: a novel urine adulterant.  

PubMed

The estimated number of employees in the United Stated screened annually for illicit drugs is approximately 20 million, with marijuana being the most frequently abused drug. Urine adulterants provide an opportunity for illicit drug users to obtain a false-negative result on commonly used primary drug screening methods such as the enzyme multiplied immunoassay technique and the fluorescence polarized immunoassay technique (FPIA). Typical chemical adulterants such as nitrites are easily detected or render the urine specimen invalid as defined in the proposed SAMHSA guidelines for specimen validity testing based on creatinine, specific gravity, and pH. Papain is a cysteine protease with intrinsic ester hydrolysis capability. The primary metabolite of the psychoactive chemical in marijuana, 11-norcarboxy-Delta9-tetrahydrocannibinol (THC-COOH), was assayed by FPIA in concentrations ranging from 25 to 500 ng/mL, at pH values ranging from 4.5 to 8, over the course of 3 days with papain concentrations ranging from 0 to 10 mg/mL. FPIA analysis of other frequently abused drugs: amphetamines, barbiturates, benzodiazepines, cocaine, opiates, and phencyclidine, along with gas chromatography-mass spectrometry (GC-MS) of THC-COOH and high-pressure liquid chromatography-ultraviolet detection (HPLC-UV) of nordiazepam was performed in order to determine if the mechanism of urine adulteration by papain was analyte specific. Control and adulterated urine specimens (n = 30) were assayed for creatinine, specific gravity, and pH to determine if papain rendered the specimens invalid based on the proposed SAMHSA guidelines. There was a direct pH, temperature, and time-dependent correlate between the increase in papain concentration and the decrease in THC-COOH concentration from the untreated control groups (p < 0.01). The average 72-h THC-COOH concentration decrease at pH 6.2 with a papain concentration of 10 mg/mL was 50%. Papain did not significantly decrease the concentration of the other drugs analyzed with the exception of nordiazepam. GC-MS of THC-COOH and HPLC-UV of nordiazepam revealed a 66% and 24% decrease in concentration of the respective analyte with 10 mg/mL papain after 24 h at room temperature (approximately 23 degrees C). No adulterated specimens were rendered invalid based on the SAMHSA guidelines. Immediate FPIA analysis is suggested to minimize the interfering effects of papain with regards to primary drug screening. PMID:16105251

Burrows, David L; Nicolaides, Andrea; Rice, Peter J; Dufforc, Michelle; Johnson, David A; Ferslew, Kenneth E

293

Urine, serum and hair monitoring of hydrofluoric acid workers  

Microsoft Academic Search

Summary To define the relationship between fluoride (F) concentration in the serum, urine and hair of workers and the concentration of hydrofluoric acid (HF) in the work environment, pre- and postshift serum and urine samples of 142 HF exposed workers and 237 unexposed workers were examined. Hair specimens were also collected for the determination of F. To determine whether external

Koichi Kono; Yasuhisa Yoshida; Misuzu Watanabe; Yukio Orita; Tomotaro Dote; Yasumori Bessho

1993-01-01

294

The influence of low blood lead concentrations on the cognitive and physical development of primary school children in Malaysia.  

PubMed

This study aimed to determine the relationship between blood lead (BPb) concentrations and cognitive and physical development in school children. A total of 169 urban children and 100 industrial children of Malay ethnicity, in the age range of 6(1/2) to 8(1/2) years, were selected. BPb was determined using GF atomic absorption spectrophotometer. The mean cognitive score (102.55) of the children from the industrial area was significantly higher than that of the urban children (95.09; P < .001). However, no significant differences were found in the BPb levels between the 2 groups (industrial, 3.75 microg/dL; urban, 3.56 microg/dL). There was significant inverse correlation between BPb and cognitive scores for all children (P < .05). The cognitive scores for all children were influenced by BPb after adjustments (P < .05). The urban children had significantly better Weight for Height and Left Arm Circumference values than those from industrial area. There was no significant correlation between BPb and the anthropometric measurements. In conclusion, low BPb influenced the cognitive development, whereas physical development was not affected. PMID:19124326

Zailina, H; Junidah, R; Josephine, Y; Jamal, H H

2008-01-01

295

Magnesium, aluminum and lead in various brain areas  

SciTech Connect

Whereas the lead concentrations were increased in brain tissue of patients with chronic alcoholism, the aluminum concentrations remained within the normal range. The magnesium concentrations were found decreased in patients with chronic alcoholism compared to normal controls. The sources for the elevated lead levels seem to be the increased intake of alcohol. The decreased magnesium levels are probably caused by an increased loss of magnesium with the urine, malnutrition, malabsorption, hormonal factors and drugs. Various neurological disorders which often accompanied chronic alcoholism may be caused or aggravated by lead encephalopathy and hypomagnesemia. Therapeutical implications may be the early substitution of magnesium deficiency in chronic alcoholism. 10 references, 5 figures.

Zumkley, H.; Bertram, H.P.; Brandt, M.; Roedig, M.; Spieker, C.

1986-01-01

296

Physiologicomathematical model for studying human exposure to organic solvents: kinetics of blood/tissue n-hexane concentrations and of 2,5-hexanedione in urine.  

PubMed Central

The physiologicomathematical model with eight compartments described allows the simulation of the absorbtion, distribution, biotransformation, excretion of an organic solvent, and the kinetics of its metabolites. The usual compartments of the human organism (vessel rich group, muscle group, and fat group) are integrated with the lungs, the metabolising tissues, and three other compartments dealing with the metabolic kinetics (biotransformation, water, and urinary compartments). The findings obtained by mathematical simulation of exposure to n-hexane were compared with data previously reported. The concentrations of n-hexane in alveolar air and in venous blood described both in experimental and occupational exposures provided a substantial validation for the data obtained by mathematical simulation. The results of the urinary excretion of 2,5-hexanedione given by the model were in good agreement with data already reported. The simulation of an exposure to n-hexane repeated five days a week suggested that the solvent accumulates in the fat tissue. The half life of n-hexane in fat tissue equalled 64 hours. The kinetics of 2,5-hexanedione resulting from the model suggest that occupational exposure results in the presence of large amounts of 2,5-hexanedione in the body for the whole working week.

Perbellini, L; Mozzo, P; Brugnone, F; Zedde, A

1986-01-01

297

Sulfur control of lead concentration during MORB genesis: clues to the origin of HIMU and FOZO sources  

NASA Astrophysics Data System (ADS)

It has been widely accepted that recycling of oceanic and continental crusts produced chemically distinct regions in the mantle, so called mantle reservoirs (FOZO, HIMU, EMI and EMII; e.g., Stracke et al. 2005). Thus the investigation of the process that produced these reservoirs would be essential to understand the material recycling in the Earth. In particular, FOZO and HIMU could be important because these reservoirs are inferred to be produced by recycling of oceanic crust that is major constituent of the subducting slab. As the recycled oceanic crust suffered subduction process to produce continental crust, the origin of the FOZO and HIMU, and continental crust could potentially be connected. Although the growth rate of the continental crust is still in debated, much of the crust seems to be formed during Archean and early Proterozoic times. In such ancient time, the subducting oceanic crust would be much more likely to be melted due to high geothermal gradient and low average age of the crust. It could follow that the recycled material observed in OIB should have experienced melting rather than dehydration because the age of recycled material is inferred to be ca 1.0-2.0 Ga (Chauvel, et al., 1992; Hofmann 1997). Nevertheless, melt-extraction process can not produce the suitable isotopic composition of OIBs. Dehydration of oceanic crust is another major process in subduction zone especially at present. In addition, the process is widely accepted as the origin of HIMU source (e.g., Kogiso et al., 1997). It might follow that HIMU magmas could be a common type of OIB as the dehydrated oceanic crust should be a major constituent of subducting slab. In spite of this expectation, occurrence of HIMU magmas is quite rare: only observed in St. Helena in the Atlantic Ocean and the Cook-Austral islands in the South Pacific Ocean. These lines of evidence could suggest that simple dehydration reaction or melting event was not suitable to produce the OIB source. For the comprehensive understanding of the relationship between FOZO, HIMU and continental crust, geochemical modeling has been conducted using trace element composition and Pb, Nd and Sr isotopic ratios. The model focuses on the chemical evolution of the magma in mod-ocean ridges that can change U, Th, Pb and S concentration in magma. In particular, the model pays special attention to the behavior of S. The result suggests that dehydration melting of oceanic crust at shallow level (amphibole stability field) can produce melt of which trace element composition is similar to bulk continental crust. In addition, the residual oceanic crust can produce Pb, Nd and Sr isotopic composition that is consistent with FOZO component at the age of 10-20 billon years. HIMU component can only be produced by the dehydration melting of oceanic crust that suffered strong crystal fractionation during the production of the oceanic crust. The fractional crystallization at mid-ocean ridges can increase U and Th concentration in oceanic crust. Sulfur solubility is also enhanced during the crystal fractionation due to iron enrichment. High sulfur content in the evolved magma leads to distribute much more lead into sulfide compared to less evolved oceanic crust. This geochemical feature could be suitable to produce HIMU source via dehydration melting. We will present a geochemical model that is focused on origin of HIMU source and the relationship between continental crust and OIB sources.

Shimoda, G.; Kogiso, T.

2008-12-01

298

Concentration, pH, and surface charge effects on cadmium and lead sorption in three tropical soils.  

PubMed

Reactions of heavy metals with soil are important in determining metal fates in the environment. Sorption characteristics of two heavy metals, Cd and Pb, in three tropical soils (Mollisol, Oxisol, and Ultisol) from Puerto Rico were assessed at varying metal concentrations (0 to 1.2 mM) and pH values (approximately 2 to 7). All soils sorbed more Pb than Cd. Sorption maxima were obtained for each metal for the Oxisol and Ultisol soils, but not the Mollisol. Sorption appeared to depend more on soil mineralogy than organic matter content. Sorption isotherms were linear within the sorption envelope with similar slopes for each soil-metal curve, when plotting metal sorption as a function of pH. Cadmium and Pb isotherms yielded average slopes of approximately 36+/-1 and 28+/-1 units (percent increase in metal sorption per 1-unit increase in pH), respectively. Metal sorption depended more on metal type than soil composition. Cadmium sorption displayed a greater pH dependence than Pb. Cadmium sorption was less than or equal to the amount of negative surface charge except at pH values greater than the point of zero net charge (PZNC). This suggests that Cd was probably sorbed via electrostatic surface reactions and/or possible inner-sphere complexation at pH > 3.7. However, the amount of Pb sorbed by the Oxisol was greater than the amount of negative surface charge, suggesting that Pb participates in inner-sphere surface reactions. Lead was sorbed more strongly than Cd in our soils and poses less of a threat to underlying ground water systems due to its lower mobility and availability. PMID:11931450

Appel, Chip; Ma, Lena

299

Changes in urine composition after trauma facilitate bacterial growth  

PubMed Central

Background Critically ill patients including trauma patients are at high risk of urinary tract infection (UTI). The composition of urine in trauma patients may be modified due to inflammation, systemic stress, rhabdomyolysis, life support treatment and/or urinary catheter insertion. Methods Prospective, single-centre, observational study conducted in patients with severe trauma and without a history of UTIs or recent antibiotic treatment. The 24-hour urine samples were collected on the first and the fifth days and the growth of Escherichia coli in urine from patients and healthy volunteers was compared. Biochemical and hormonal modifications in urine that could potentially influence bacterial growth were explored. Results Growth of E. coli in urine from trauma patients was significantly higher on days 1 and 5 than in urine of healthy volunteers. Several significant modifications of urine composition could explain these findings. On days 1 and 5, trauma patients had an increase in glycosuria, in urine iron concentration, and in the concentrations of several amino acids compared to healthy volunteers. On day 1, the urinary osmotic pressure was significantly lower than for healthy volunteers. Conclusion We showed that urine of trauma patients facilitated growth of E. coli when compared to urine from healthy volunteers. This effect was present in the first 24 hours and until at least the fifth day after trauma. This phenomenon may be involved in the pathophysiology of UTIs in trauma patients. Further studies are required to define the exact causes of such modifications.

2012-01-01

300

Urine drug screen  

MedlinePLUS

... the container from the urine stream. Give the container to the health care provider or assistant. Wash your hands again with soap and water. The sample is then taken to the laboratory for evaluation.

301

Effect of sub-minimum inhibitory concentrations of ciprofloxacin, amikacin and colistin on biofilm formation and virulence factors of Escherichia coli planktonic and biofilm forms isolated from human urine  

PubMed Central

The aim of this study was to determine the effect of subinhibitory concentrations (sub-MICs) of ciprofloxacin, amikacin and colistin on biofilm formation, motility, curli fimbriae formation by planktonic and biofilm cells of E. coli strains isolated from the urine of patients with various urinary system infections. Quantification of biofilm formation was carried out using a microtiter plate assay and a spectrophotometric method. Bacterial enumeration was used to assess the viability of bacteria in the biofilm. Curli expression was determined by using YESCA agar supplemented with congo red. Using motility agar the ability to move was examined. All the antibiotics used at sub-MICs reduced biofilm formation in vitro, decreased the survival of bacteria, but had no effect on the motility of planktonic as well as biofilm cells. The inhibitory effect of sub-MICs of antimicrobial agents on curli fimbriae formation was dependent on the form in which the bacteria occurred, incubation time and antibiotic used. Our results clearly show that all the three antibiotics tested reduce biofilm production, interfere with curli expression but do not influence motility. This study suggests that ciprofloxacin, amikacin and colistin may be useful in the treatment of biofilm-associated infections caused by E. coli strains.

Wojnicz, Dorota; Tichaczek-Goska, Dorota

2013-01-01

302

Concentrations and origins of atmospheric lead and other trace species at a rural site in northern China  

Microsoft Academic Search

In this study we analyze the ambient levels of lead and other trace species in the bulk aerosol samples from a rural site ?70 km ESE of Beijing in spring 2005. Lead (0.28 ± 0.24 ?g\\/m3, average ± standard deviation), along with several pollution-related trace elements, was enriched by over 100 fold relative to the Earth’s crust. The ambient lead

Tianxue Wen; Zhanqing Li; Russell R. Dickerson; Yongjie Yang; Yanan Zhao; Yuesi Wang; Si-Chee Tsay

2010-01-01

303

Estimating the precipitation potential in urine-collecting systems  

Microsoft Academic Search

Precipitation in urine-separating toilets (NoMix toilets) and waterless urinals causes severe maintenance problems and can strongly reduce the content of soluble phosphate. In this study, we present a computer model for estimating the precipitation potential (PP) in urine-collecting systems. Calculating the PP enables to predict the composition and mass concentration of precipitates. We used our computer model for investigating how

Kai M. Udert; Tove A. Larsen; Willi Gujer

2003-01-01

304

Concentrations and loads of cadmium, zinc, and lead in the main stem Coeur d'Alene River, Idaho—March, June, September, and October 1999  

USGS Publications Warehouse

of the effects of different river discharges and lake levels of Coeur d'Alene Lake on the transport of cadmium, zinc, and lead within the main stem Coeur d'Alene River. In particular, water-quality data and loads during a broad range of hydrologic conditions were examined to determine if the river channel, flood plain, and associated ground water along the main stem Coeur d'Alene River acted as sources or sinks of trace elements. Water-quality samples were collected at six riverine stations and one lake station along a 35-mile reach during March, June, September, and October of 1999. Samples were analyzed for whole-water recoverable, filtered (0.45 micrometer), and dissolved (0.01 micrometer) concentrations of cadmium, zinc, and lead. Concentrations and loads of cadmium and zinc measured during the four sampling trips were predominately in the filtered and dissolved fraction ,rather than particulate. The smallest concentrations were measured during the June sampling trip when flows were high and snowmelt runoff diluted riverine concentrations. Conversely, the largest concentrations were measured during the latter two sampling trips when flows were low because a larger proportion of the river's discharge was contributed by ground-water inflow. During each sampling trip, cadmium and zinc concentrations generally decreased in a downstream directioeven as discharge increased in a downstream direction. Spatial and temporal trends exhibited by lead concentrations and loads during the four sampling trips were different from those of cadmium and zinc because of the propensity for lead to adsorb to sediment particles. Whole-water recoverable lead concentrations and loads during the four sampling trips were predominantly in the particulate fraction, with filtered and dissolved concentrations and loads composing a much smaller proportion of the recoverable fraction compared to cadmium and zinc. Filtered lead concentrations generally increased at a faster rate in the downstream direction than dissolved lead concentrations; thus, colloidallead either was being formed by complexation reactions or being added by sediment erosion in the downstream direction.

Woods, P. F.

2001-01-01

305

[Interannual variation patterns of heavy metals concentrations in tree rings of Larix gmelinii near Xilin Lead-zinc Mine, Yichun of Northeast China].  

PubMed

By using dendro-environmental methods, this paper measured and analyzed the variations of five heavy metals (Pb, Cd, Zn, Cu, and Mn) concentrations in the tree rings of Larix gmelinii near Xilin Lead-zinc Mine, Yichun of Northeast China. Among the test heavy metals, the Mn concentration in the tree rings was the highest, while the Cd concentration was the lowest. The Cd, Zn, and Cu concentrations in the tree rings near the ground (0.3 m high from the ground, D0.3) were significantly higher than those at breast height (1.3 m high from the ground, D1.3), while the Pb and Mn concentrations at the two heights had less difference. In 1987-2010, the Pb concentration in the tree rings had a slight increase, but the Cd, Zn, Cu, and Mn concentrations presented a decreasing trend. The Cd concentration decreased most obviously, while the Zn, Cu, and Mn concentrations decreased after an initial increase. With the increase of tree ring width, the Pb concentration decreased, while the Cd, Zn, Cu, and Mn concentrations were in adverse. The relationships between the Pb and other four heavy metals concentrations in the tree rings near the ground and at breast height had definite differences. Near the ground, the Pb concentration showed a significant positive correlation with the other four heavy metals concentrations, but at breast height, less correlation was observed, and even, the Cd concentration decreased significantly with increasing Pb concentration. The variations of the heavy metals concentrations in the L. gmelinii tree rings could be affected by the production and mining activities of Xilin Lead-zinc Mine, an thus, it would be possible to use the Pb concentration in the tree rings to reconstruct the mining his tory of the study area. At present, the Pb concentration in the tailing wastes has polluted the surrounding environments near Xilin Lead-zinc Mine. Therefore, countermeasures should be adopted to manage the heavy metals in tailing wastes if the Mine would be continued to be mined. PMID:24066537

Hu, Shen; Wang, Xiao-Chun; Yang, Jin-Yan

2013-06-01

306

TOTAL AND EXTRACTABLE LEAD AND ARSENIC CONCENTRATIONS IN US LONG-TERM ORCHARD SOILS AND POTENTIAL ACCUMULATION BY VEGETABLE CROPS  

Technology Transfer Automated Retrieval System (TEKTRAN)

Lead arsenate was used as an insecticide in the U.S. from 1900 to 1950 to control Codling moth in apple orchards. As a result, these soils are contaminated with lead (Pb) and arsenic (As). Concerns have been raised about conversion of land use of such Pb and As rich soils, either for vegetable crops...

307

Reevaluation of blood mercury, lead and cadmium concentrations in the Inuit population of Nunavik (Québec): a cross-sectional study  

Microsoft Academic Search

BACKGROUND: Arctic populations are exposed to mercury, lead and cadmium through their traditional diet. Studies have however shown that cadmium exposure is most often attributable to tobacco smoking. The aim of this study is to examine the trends in mercury, lead and cadmium exposure between 1992 and 2004 in the Inuit population of Nunavik (Northern Québec, Canada) using the data

Julie Fontaine; Éric Dewailly; Jean-Louis Benedetti; Daria Pereg; Pierre Ayotte; Serge Déry

2008-01-01

308

Selenium Levels in Human Blood, Urine, and Hair in Response to Exposure via Drinking Water.  

National Technical Information Service (NTIS)

Blood, hair, urine and tap water samples were obtained from participants in a population exposed to varying amounts of selenium via water from home wells. Concentrations of selenium in urine and hair produced significant positive correlations with well-wa...

J. L. Valentine H. K. Kang G. H. Spivey

1978-01-01

309

Procedure for the Rapid Analysis of Large Numers of Urine Samples for Drugs.  

National Technical Information Service (NTIS)

The reported widespread use of narcotics and dangerous drugs has resulted in a demand for urine testing. The following procedure was developed for the rapid analysis of large numbers of urine samples for low concentrations of narcotics and dangerous drugs...

A. M. Dominguez L. R. Goldbaum P. Santinga

1972-01-01

310

Variability of Organophosphorous Pesticide Metabolite Levels in Spot and 24-hr Urine Samples Collected from Young Children during 1 Week  

PubMed Central

Background: Dialkyl phosphate (DAP) metabolites in spot urine samples are frequently used to characterize children’s exposures to organophosphorous (OP) pesticides. However, variable exposure and short biological half-lives of OP pesticides could result in highly variable measurements, leading to exposure misclassification. Objective: We examined within- and between-child variability in DAP metabolites in urine samples collected during 1 week. Methods: We collected spot urine samples over 7 consecutive days from 25 children (3–6 years of age). On two of the days, we collected 24-hr voids. We assessed the reproducibility of urinary DAP metabolite concentrations and evaluated the sensitivity and specificity of spot urine samples as predictors of high (top 20%) or elevated (top 40%) weekly average DAP metabolite concentrations. Results: Within-child variance exceeded between-child variance by a factor of two to eight, depending on metabolite grouping. Although total DAP concentrations in single spot urine samples were moderately to strongly associated with concentrations in same-day 24-hr samples (r ? 0.6–0.8, p < 0.01), concentrations in spot samples collected > 1 day apart and in 24-hr samples collected 3 days apart were weakly correlated (r ? –0.21 to 0.38). Single spot samples predicted high (top 20%) and elevated (top 40%) full-week average total DAP excretion with only moderate sensitivity (? 0.52 and ? 0.67, respectively) but relatively high specificity (? 0.88 and ? 0.78, respectively). Conclusions: The high variability we observed in children’s DAP metabolite concentrations suggests that single-day urine samples provide only a brief snapshot of exposure. Sensitivity analyses suggest that classification of cumulative OP exposure based on spot samples is prone to type 2 classification errors.

Kogut, Katherine; Eisen, Ellen A.; Jewell, Nicholas P.; Quiros-Alcala, Lesliam; Castorina, Rosemary; Chevrier, Jonathan; Holland, Nina T.; Barr, Dana Boyd; Kavanagh-Baird, Geri; Eskenazi, Brenda

2012-01-01

311

Lead concentration in blood samples of humans and animals near an industrial waste dump in Sao Paulo, Brazil.  

PubMed

Blood lead was determined in 7 adults, 2 children, 1 bull, 11 cows, and 3 calves living on agricultural land near an industrial waste site. An unexposed human control group was composed of 2 adults and 2 children. Mean blood lead from the exposed group was 4.6 micrograms/dl for adults, 5.1 micrograms/dl for children, 1.3 micrograms/dl for the bull, 1.2 micrograms/dl for cows, and 1.8 micrograms/dl for calves. Unexposed adults had 4.1 micrograms/dl and children had 3.7 micrograms/dl lead blood. The blood lead content did not suggest a health hazard from lead for either humans or animals. PMID:10434383

Kuno, R; Fernicola, N A; Roquetti-Humayta, M H; de Campos, A E; Filha, M T

1999-08-01

312

Diet effects on urine composition of cattle and N2O emissions.  

PubMed

Ruminant production contributes to emissions of nitrogen (N) to the environment, principally ammonia (NH3), nitrous oxide (N2O) and di-nitrogen (N2) to air, nitrate (NO3 -) to groundwater and particulate N to surface waters. Variation in dietary N intake will particularly affect excretion of urinary N, which is much more vulnerable to losses than is faecal N. Our objective is to review dietary effects on the level and form of N excreted in cattle urine, as well as its consequences for emissions of N2O. The quantity of N excreted in urine varies widely. Urinary N excretion, in particular that of urea N, is decreased upon reduction of dietary N intake or an increase in the supply of energy to the rumen microorganisms and to the host animal itself. Most of the N in urine (from 50% to well over 90%) is present in the form of urea. Other nitrogenous components include purine derivatives (PD), hippuric acid, creatine and creatinine. Excretion of PD is related to rumen microbial protein synthesis, and that of hippuric acid to dietary concentration of degradable phenolic acids. The N concentration of cattle urine ranges from 3 to 20 g/l. High-dietary mineral levels increase urine volume and lead to reduced urinary N concentration as well as reduced urea concentration in plasma and milk. In lactating dairy cattle, variation in urine volume affects the relationship between milk urea and urinary N excretion, which hampers the use of milk urea as an accurate indicator of urinary N excretion. Following its deposition in pastures or in animal houses, ubiquitous microorganisms in soil and waters transform urinary N components into ammonium (NH4 +), and thereafter into NO3 - and ultimately in N2 accompanied with the release of N2O. Urinary hippuric acid, creatine and creatinine decompose more slowly than urea. Hippuric acid may act as a natural inhibitor of N2O emissions, but inhibition conditions have not been defined properly yet. Environmental and soil conditions at the site of urine deposition or manure application strongly influence N2O release. Major dietary strategies to mitigating N2O emission from cattle operations include reducing dietary N content or increasing energy content, and increasing dietary mineral content to increase urine volume. For further reduction of N2O emission, an integrated animal nutrition and excreta management approach is required. PMID:23739471

Dijkstra, J; Oenema, O; van Groenigen, J W; Spek, J W; van Vuuren, A M; Bannink, A

2013-06-01

313

Concentrations and origins of atmospheric lead and other trace species at a rural site in northern China  

NASA Astrophysics Data System (ADS)

In this study we analyze the ambient levels of lead and other trace species in the bulk aerosol samples from a rural site ˜70 km ESE of Beijing in spring 2005. Lead (0.28 ± 0.24 ?g/m3, average ± standard deviation), along with several pollution-related trace elements, was enriched by over 100 fold relative to the Earth's crust. The ambient lead levels showing large synoptic variations were well-correlated with other anthropogenic pollutants (e.g., CO and SO2). The Unmix receptor model resolved four factors in the aerosol composition data: a biomass burning source, an industrial and coal combustion source, a secondary aerosol source, and a dust source. The first three sources were strongest in weak southerly winds ahead of cold fronts, while the dust source peaked in strong northerly winds behind cold fronts. The second source, primarily representing emissions from industrial processes and relatively small-scale coal burning such as in home and institutional heating, was identified as the main source of ambient lead in this study. Mobile sources might also contribute to this factor, but there was no distinct evidence of emissions due to combustion of leaded gasoline, despite a correlation between lead and CO. Potential source contribution function, calculated from backward trajectories and aerosol composition, further reveals that lead observed in this study was predominantly from the populated and industrialized areas to the south and SW of Xianghe, rather than Beijing to the west. Our results and several recent studies show that the lead levels in suburban areas near big cities in China, although generally lower than those in industrial districts and urban areas, are substantial (near or above 0.15 ?g/m3). More extensive studies on airborne lead and its emission sources in China are called for.

Li, Can; Wen, Tianxue; Li, Zhanqing; Dickerson, Russell R.; Yang, Yongjie; Zhao, Yanan; Wang, Yuesi; Tsay, Si-Chee

2010-04-01

314

Blood lead concentration and children’s anthropometric dimensions in the Third National Health and Nutrition Examination Survey (NHANES III), 1988-1994  

Microsoft Academic Search

Objective: To assess the association between lead exposure and children’s physical growth. Design: Cross-sectional analysis of data from the Third National Health and Nutrition Examination Survey, 1988-1994. Participants: A total of 4391 non-Hispanic white, non-Hispanic black, and Mexican-American children age 1 to 7 years. Measurements and Results: We investigated the association between blood lead concentration and stature, head circumference, weight,

Carol Ballew; Laura Kettel Khan; Rachel Kaufmann; Ali Mokdad; Dayton T. Miller; Elaine W. Gunter

1999-01-01

315

Concentration of four heavy metals (cadmium, lead, mercury, and arsenic) in organs of two cyprinid fish ( Cyprinus carpio and Capoeta sp.) from the Kor River (Iran)  

Microsoft Academic Search

Concentration of heavy metals in aquatic animals mainly occurs due to industrial contamination. In this study, the concentrations\\u000a of four heavy metals (cadmium, lead, mercury, and arsenic) in organs of two cyprinid fish and in water collected from three\\u000a sections of the Kor River, Iran were determined using the inductively coupled plasma method. Pathological and hormonal changes\\u000a due to metal

Mansour Ebrahimi; Mahnaz Taherianfard

2010-01-01

316

Urine Proteome Analysis in Murine Nephrotoxic Serum Nephritis  

Microsoft Academic Search

Background: Urine contains serum proteins filtered by the glomerulus or secreted by the renal tubules and proteins produced locally by the urinary tract. Proteomic analysis of urine holds the potential as a noninvasive means of studying or monitoring disease activity. In mice, large concentrations of albumin and lipocalins have complicated the ability to identify urinary biomarkers in disease models. Methods:

Scott E. Wenderfer; William P. Dubinsky; Mayra Hernandez-Sanabria; Michael C. Braun

2009-01-01

317

Determination of lead in sea-water with a graphite furnace atomic absorption spectrometer and an improved automatic on-line pre-concentration system  

NASA Astrophysics Data System (ADS)

An improved automatic on-line pre-concentration system for graphite furnace atomic absorption spectrometry (GFAAS) for the determination of trace metals in sea-water was developed. This system was modified from a Perkin-Elmer AS-40 autosampler by mounting a silica gel C 18 microcolumn near the tip of the autosampler capillary. The pre-concentration procedure was performed by using a four-way distribution valve and controlled by a programmable controller. The pre-concentration system developed previously was improved by using a peristaltic pump to replace the reciprocating pumps, a newly designed tube bed adjuster to release the back-pressure in the pre-concentration system, and a better control program, such that on-line pre-concentration became more reliable and fully automatic. The chelating agent ammonium pyrolidinedithiocarbamate (APDC) and a miniature column packed with 5 mg of C 18 silica gel were used for pre-concentration. This system was tested by analyzing the lead content in reference standard sea-water samples. A sample volume of only 2 ml was required to determine lead in sea-water. The relative limit of detection of lead was 3.5 pg/ml.

Liu, Zhen-Shan; Huang, Shang-Da

1995-03-01

318

Association of anemia, child and family characteristics with elevated blood lead concentrations in preschool children from Montevideo, Uruguay.  

PubMed

Elevated blood lead levels (BPbs) have been identified in Uruguayan children in the La Teja neighborhood of Montevideo, but the extent of lead exposure in other city areas is unknown. Sources and predictors of exposure also remain understudied in this population. In 2007, the authors screened lead and hemoglobin levels in capillary blood of 222 preschool children from several areas of Montevideo, Uruguay, and identified predictors of elevated BPbs. Mean BPb was 9.0 +/- 6.0 microg/dL and 32.9% of children had levels >or= 10microg/dL. Mean hemoglobin level was 10.5 +/- 1.5 g/dL, with 44.1% having levels <10.5g/dL. Older child age, hemoglobin <10.5g/dL, and putting fingers/toys in the mouth were associated with higher BPbs. Young maternal age, less education, father's job with potential risk of lead exposure, and fewer family possessions were also associated with higher BPbs. Pediatric lead exposure is a public health problem in Uruguay, with children experiencing elevated BPbs at a young age. PMID:20439228

Queirolo, Elena I; Ettinger, Adrienne S; Stoltzfus, Rebecca J; Kordas, Katarzyna

319

"Pink urine" in morbidly obese patients following gastric partitioning.  

PubMed Central

A pink coating on the inner surface of plastic urinary tubing, which gave the impression that the urine was pink, had frequently been noted 4 to 24 hours following gastric partitioning by means of a stapler in morbidly obese patients. A study was therefore done in 187 such patients as well as in 14 patients of normal weight who had undergone abdominal surgery of comparable magnitude. Postoperatively "pink urine" was observed in 32% of the obese patients but in none of the nonobese patients; however, a pink sediment remained following centrifugation of urine collected postoperatively from all the obese patients. Microscopy of this sediment showed crystals of uric acid dihydrate; these were infrequent in the preoperative specimens but present in high concentration in the postoperative specimens, particularly those of "pink urine". X-ray diffraction analysis confirmed the nature of the crystals. Preoperatively the obese patients had high-normal serum levels of uric acid. Postoperatively in all the groups of patients the serum levels of uric acid decreased while the urine levels and the urinary clearance of uric acid increased; the last two values, however, were significantly greater, both preoperatively and postoperatively, in those who were morbidly obese. Compared with the patients who did not have "pink urine" the patients with "pink urine" were significantly more obese and had a significantly lower postoperative urine pH. The latter also had a marked postoperative increase in urine osmolality and were the only patients to have a significant postoperative decrease in urine output. Thus, the pink colour of this group's urine was attributed to precipitation of uric acid crystals, fostered by a decrease in pH and an increase in concentration of the urine. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5

Deitel, M.; Thompson, D. A.; Saldanha, C. F.; Ramshaw, P. J.; Patterson, M. C.; Pritzker, K. P.

1984-01-01

320

Detection of chrysotile asbestos in workers urine  

SciTech Connect

Urinary asbestos concentrations were evaluated as an indicator of occupational exposure to chrysotile asbestos via inhalation and ingestion. Detection of asbestos in the urine represents the first step in developing a biological indicator of exposure. Such an indicator could be used to supplement exposure data from workplace air sampling. A biological indicator would be particularly valuable in evaluating workers with intermittent airborne asbestos exposures and in determining if airborne exposure results in penetration of asbestos through the lung or gastro-intestinal tract. Transmission electron microscopy was selected as the most sensitive technique for identification of all sizes of asbestos fibers which might appear in the urine. The levels of chrysotile asbestos detected in the urine of five workers were significantly greater than the asbestos concentrations in matched field blanks. Also, the workers urinary asbestos levels were significantly greater than the concentrations found in the control group. Finally, the levels of chrysotile asbestos detected in the urine of two of six controls were significantly greater than those in matched field blanks. Although the project was not specifically designed to correlate urinary and airborne asbestos concentrations, preliminary data indicated that a correlation did not exist between these factors.

Finn, M.B.; Hallenbeck, W.H.

1985-03-01

321

Concentrations of cadmium, manganese, copper, zinc, and lead in the tissues of the oyster (Crassostrea iredalei) obtained from Setiu Lagoon, Terengganu, Malaysia  

Microsoft Academic Search

Heavy metals pollution in aquatic environments is a major problem contributing to human health issues. The study of these pollutants through bioindicators such as the oyster Crassostrea iredalei is important for (1) determining the levels and sources and (2) regulating the quantity of pollutants. The concentrations of cadmium (Cd), manganese (Mn), copper (Cu), zinc (Zn), and lead (Pb) in tissues

M. Azlisham; V. J. Vedamanikam; N. A. M. Shazilli

2009-01-01

322

Coupling lead isotopes and element concentrations in epiphytic lichens to track sources of air emissions in the Alberta Oil Sands Region  

EPA Science Inventory

A study was conducted that coupled use of element concentrations and lead (Pb) isotope ratios in the lichen Hypogymnia physodes collected during 2002 and 2008, to assess the impacts of air emissions from the Alberta Oil Sands Region (AOSR, Canada) mining and processing operations...

323

Cadmium, lead, calcium, magnesium, copper, and zinc concentrations in human infant tissues: their relationship to Sudden Infant Death Syndrome  

Microsoft Academic Search

The purpose of this study was to determine whether there was any evidence of an excess of the toxic elements, cadmium and lead, or a deficiency of any of the essential elements, calcium, magnesium, copper, and zinc, in the tissues of infants who died of Sudden Infant Death Syndrome (SIDS) as compared to those of infants who died of other

1981-01-01

324

The effect of malathion, diazinon, and various concentrations of zinc, copper, nickel, lead, iron, and mercury on fish  

Microsoft Academic Search

Acute and chronic toxicity tests for malathion, diazinon, copper (Cu), mercury (Hg), lead (Pb), zinc (Zn), nickel (Ni), and\\u000a iron (Fe) were conducted. Mortalities ofBarilius vagra andCyprinus carpio (common carp) were variable but LC50-96 hr were similar for pesticides. AdultB. vagra seem to be more sensitive to malathion than juvenile carp. Both juvenile carp and adultB. vagra were extremely sensitive

M. K. Alam; O. E. Maughan

1992-01-01

325

Critical soil concentrations of cadmium, lead and mercury in view of health effects on humans and animals  

Microsoft Academic Search

To assess the impact of elevated concentrations of metals in terrestrial ecosystems, a major distinction should be made in risks\\/effects of heavy metals related to (i) the soil ecosystem (soil organisms\\/processes and plants) and (ii) human health or animal health resulting from bioaccumulation. The latter effect is related to the phenomenon that a chemical accumulates in species through different trophic

Vries de W; P. F. A. M. Romkens; G. Schutze

2007-01-01

326

Do the soft tissues of Helix aspersa serve as a quantitative sentinel of predicted free lead concentrations in soils?  

Microsoft Academic Search

Previous research suggests that free metal concentrations in soils are the best correlate of the proportion available for uptake, especially by plants. The same may be true for animals which ingest soil, such as earthworms and gastropod molluscs. Using predictions from a simple model proposed by Sauvé et al. [Environ. Pollut. (1997) 149] and based on soil pH and total

Alan Beeby; Larry Richmond

2003-01-01

327

Concentrations of copper, zinc, cadmium and lead in rabbitfish ( Siganus oramin) collected in Victoria Harbour, Hong Kong  

Microsoft Academic Search

The urban area of Hong Kong supports a population of about 4 million people, with an annual production of several hundred million tonnes of untreated domestic and industrial effluent. This causes significant marine pollution problems in Victoria Harbour. Moreover, urban runoff also brings pollutants to Victoria Harbour. This paper presents preliminary data on the concentrations of heavy metals from different

King Ming Chan

1995-01-01

328

Advanced Urine Toxicology Testing  

Microsoft Academic Search

Urine toxicology screening testing is an important standard of care in the addiction and pain treatment setting, offering a reproducible, unbiased, and accurate laboratory test to monitor patients and provide objective support for clinical observations. It has been shown that physicians do not have proficiency in the ordering or interpretation of these tests. This article is an attempt to respond

Peter L. Tenore

2010-01-01

329

HCG in urine  

MedlinePLUS

... Other HCG tests include: HCG in blood serum - qualitative HCG in blood serum - quantitative Pregnancy test ... Urine HCG tests are a common method of determining if a woman is pregnant. The best time to test for pregnancy at home is after you miss your period.

330

Bacterial Assay of Urine.  

National Technical Information Service (NTIS)

The dip-slide technique for bacterial assay of urine has been found to be a competent method for isolating the usual organisms responsible for urinary tract infection. Being a simple device, reliable in transport, and commercially available, it would appe...

J. E. Sippel Z. Farid A. S. Diab

1972-01-01

331

Determination of catecholamines in plasma and urine.  

PubMed

For more than 20 years, measurement of catecholamines in plasma and urine in clinical chemistry laboratories has been the cornerstone of the diagnosis of neuroendocrine tumors deriving from the neural crest such as pheochromocytoma (PHEO) and neuroblastoma (NB), and is still used to assess sympathetic stress function in man and animals. Although assay of catecholamines in urine are still considered the biochemical standard for the diagnosis of NB, they have been progressively abandoned for excluding/confirming PHEOs to the advantage of metanephrines (MNs). Nevertheless, catecholamine determinations are still of interest to improve the biochemical diagnosis of PHEO in difficult cases that usually require a clonidine-suppression test, or to establish whether a patient with PHEO secretes high concentrations of catecholamines in addition to metanephrines. The aim of this chapter is to provide an update about the catecholamine assays in plasma and urine and to show the most common pre-analytical and analytical pitfalls associated with their determination. PMID:24094641

Grouzmann, Eric; Lamine, Faiza

2013-07-09

332

Survival of feline mycoplasmas in urine.  

PubMed Central

The effects of length of incubation and urine osmolality on the survival of feline mycoplasmas and ureaplasmas and representative gram-positive and gram-negative bacteria in synthetic urine which approximated the osmolality of normal cat urine were investigated. Both Escherichia coli and Staphylococcus aureus withstood the effects of increasing osmotic pressure. In the most concentrated urine, significant decreases (P less than 0.001) in CFU were observed for E. coli at exposure times of 30 min and longer. S. aureus was not affected by longer exposure or increased osmotic strength. Both Mycoplasma felis and Mycoplasma gateae were affected adversely by longer exposure times and high osmotic strength (P less than 0.001). A Ureaplasma sp. was not adversely affected except at very high (greater than or equal to 2,980 mosM) osmotic strengths or after prolonged incubation (120 min) at relatively high (1,976 mosM) osmotic strengths (P less than 0.001). The failure of both M. felis and M. gateae to survive under osmotic conditions present in normal feline urine suggests that it is unlikely that these mycoplasmas are involved in urinary disorders in cats.

Brown, M B; Stoll, M; Maxwell, J; Senior, D F

1991-01-01

333

Survival of feline mycoplasmas in urine.  

PubMed

The effects of length of incubation and urine osmolality on the survival of feline mycoplasmas and ureaplasmas and representative gram-positive and gram-negative bacteria in synthetic urine which approximated the osmolality of normal cat urine were investigated. Both Escherichia coli and Staphylococcus aureus withstood the effects of increasing osmotic pressure. In the most concentrated urine, significant decreases (P less than 0.001) in CFU were observed for E. coli at exposure times of 30 min and longer. S. aureus was not affected by longer exposure or increased osmotic strength. Both Mycoplasma felis and Mycoplasma gateae were affected adversely by longer exposure times and high osmotic strength (P less than 0.001). A Ureaplasma sp. was not adversely affected except at very high (greater than or equal to 2,980 mosM) osmotic strengths or after prolonged incubation (120 min) at relatively high (1,976 mosM) osmotic strengths (P less than 0.001). The failure of both M. felis and M. gateae to survive under osmotic conditions present in normal feline urine suggests that it is unlikely that these mycoplasmas are involved in urinary disorders in cats. PMID:2056047

Brown, M B; Stoll, M; Maxwell, J; Senior, D F

1991-05-01

334

Challenges in urine bioanalytical assays: overcoming nonspecific binding.  

PubMed

Dr Allena Ji is the Director of Bioanalytical Services, XenoBiotic Laboratories, Inc., NJ, USA. She has worked in the bioanalytical field for many years and accumulated rich experience in LC-MS/MS method development, method validation and sample analysis under GLP compliance in large pharmaceutical company and contract laboratory settings. In the past 10 years, Allena worked at Pfizer (Legacy of Wyeth) and investigated many small-molecule drug candidates for their nonspecific binding in urine assays. Nonspecific binding of compounds results in a severe underestimation of the compounds' concentrations and poor precision and accuracy in urine bioanalytical assays. To overcome nonspecific binding in urine assays, Allena and her colleagues developed a series of practical approaches for urine method development. By adding an appropriate anti-adsorptive agent at its optimum concentration to the urine collection containers, the nonspecific binding can be blocked. Urine assays have much higher hurdles than plasma assays due to nonspecific binding and variability of urine pH, salt concentration, volume and solubility of drug(s) in urine. A simple and systematic approach for urine method development is emphasized in this paper. Nonspecific binding is a very serious issue in bioanalytical urine assays where a compound(s) adsorbs to the container wall. The adsorption happens frequently in urine assays because urine lacks proteins and lipids that can bind to the analytes or solubilize lipophilic analytes. Therefore, urine bioanalytical assays tend to suffer from analyte losses more often than plasma assays. In the past decade, there have been many methods described to overcome nonspecific adsorption in urine assays based on individual analyte characteristics. However, a common and simple method development approach for various analytes has not been discussed and summarized. In this article we demonstrate, discuss and summarize a common approach to urine method development with a focus on overcoming adsorption issues. The advantages and limitations of commonly used anti-adsorptive agents, such as bovine serum albumin, zwitterionic detergents such as CHAPS, sodium dodecyl benzene sulfonate, ?-cyclodextrin, Tween 80 and Tween 20 are discussed. PMID:21083286

Ji, Allena Ji; Jiang, Zhiping; Livson, Yuliya; Davis, Jennifer Ann; Chu, Jasper Xuegong; Weng, Naidong

2010-09-01

335

Relationships Between Immunoreactive Estrone and Estradiol in Milk, Blood, and Urine of Dairy Cows1  

Microsoft Academic Search

Quantities of immunoreactive estrone and estradiol in blood plasma, urine, and milk were measured during the estrous cycle and pregnancy of cows. The ob- jectives were to develop a radio}mmtmo- assay procedure for quantifying estro- gen in milk and urine and to compare changes in milk estrogen with those in blood plasma and urine. Concentrations of estrone and estradiol in

E. L. Monk; R. E. Erb; T. A. Mollett

1975-01-01

336

Fertilization of rye grass with carbamazepine, ibuprofen, and 17?- ethinylestradiol spiked urine - a greenhouse experiment  

Microsoft Academic Search

Urine is seen as an alternative fertilizer for agriculture as it contains relatively high concentrations of nitrogen, phosphorus, and potassium. But this usage of urine includes the risk of spreading pharmaceutical residues on to agricultural fields. In this study the uptake of carbamazepine, ibuprofen, and 17?-ethinylestradiol through rye grass fertilized with spiked male urine was investigated and analyzed by GC\\/MS.

Martina Winker; Holger Gulyas; Ralf Otterpohl; Joachim Clemens

337

Low-cost struvite production using source-separated urine in Nepal  

Microsoft Academic Search

This research investigated the possibility of transferring phosphorus from human urine into a concentrated form that can be used as fertilizer in agriculture. The community of Siddhipur in Nepal was chosen as a research site, because there is a strong presence and acceptance of the urine-diverting dry toilets needed to collect urine separately at the source. Furthermore, because the mainly

B. Etter; E. Tilley; R. Khadka; K. M. Udert

2011-01-01

338

Latex agglutination for rapid detection of Pseudomonas pseudomallei antigen in urine of patients with melioidosis  

Microsoft Academic Search

A latex agglutination test for the detection of Pseudomonas pseudomallei antigen in urine was evaluated for the rapid diagnosis of melioidosis. With unconcentrated urine, antigen was detected in only 18% of patients with melioidosis overall. However, when urine was concentrated 100-fold, antigen was detected in 47% overall and in 67% of patients with septicaemia or disseminated infection, in whom a

M D Smith; V Wuthiekanun; A L Walsh; N Teerawattanasook; V Desakorn; Y Suputtamongkol; T L Pitt; N J White

1995-01-01

339

Determination of the geographic origin of rice by chemometrics with strontium and lead isotope ratios and multielement concentrations.  

PubMed

The objective of this study was to develop a technique for determining the country of origin of rice in the Japanese market. The rice samples included a total of 350 products grown in Japan (n = 200), the United States (n = 50), China (n = 50), and Thailand (n = 50). In this study, (87)Sr/(86)Sr and Pb isotope ((204)Pb, (206)Pb, (207)Pb, and (208)Pb) ratios and multielement concentrations (Al, Fe, Co, Ni, Cu, Rb, Sr, and Ba) were determined by high-resolution inductively coupled plasma mass spectrometry. By combining three chemometric techniques based on different principles and determination criteria, the countries of origin of rice were determined. The predictions made by 10-fold cross-validation were around 97% accurate. The presented method demonstrated the effectiveness of determining the geographic origin of an agricultural product by combining several chemometric techniques using heavy element isotope ratios and multielement concentrations. PMID:22280009

Ariyama, Kaoru; Shinozaki, Miyuki; Kawasaki, Akira

2012-02-08

340

Critical Soil Concentrations of Cadmium, Lead, and Mercury in View of Health Effects on Humans and Animals  

Microsoft Academic Search

To assess the impact of elevated concentrations of metals in terrestrial ecosystems, a major distinction should be made in\\u000a risks\\/effects of heavy metals related to (i) the soil ecosystem (soil organisms\\/processes and plants) and (ii) human health\\u000a or animal health resulting from bioaccumulation. The latter effect is related to the phenomenon that a chemical accumulates\\u000a in species through different trophic

Wim de Vries; Paul F. A. M. Römkens; Gudrun Schütze

341

Microelements in stones, urine, and hair of stone formers: a new key to the puzzle of lithogenesis?  

PubMed

The role of trace elements in lithogenesis is still unclear. The aim of this study was to evaluate the levels of elements in urinary stones and in the urine and hair of stone formers to identify these elements that have synergic correlations in studied materials and may contribute to lithogenesis. A total of 219 consecutive patients with idiopathic upper urinary tract stones were prospectively enrolled in the study. Urine and hair samples were collected from all patients. The content of the stone was evaluated using atomic absorption spectrometry, spectrophotometry, and colorimetric methods. The analysis of 29 elements in stones and hair and 21 elements in urine was performed using inductively coupled plasma-atomic emission spectrometry. The strength of correlation was described with the value of Spearman's rank correlation coefficient. The positive correlation between concentration of sodium, potassium, magnesium, barium, vanadium, zinc, silicon, phosphorus, and iodine in phosphate stones was observed. Only a few incidental correlations between the composition of stones and the distribution of elements in urine and in hair were found. There were 109 positive two-element correlations between two materials. The most common were observed for vanadium, aluminum, lead, cobalt, and molybdenum. Two-element positive correlations for all samples were established only for three elements: vanadium, lead, and aluminum. Results indicate that analysis of particular elements in hair and urine cannot predict the composition of urinary stones. This study showed, for the first time, correlations between the levels of vanadium, lead, and aluminum in the stones, urine, and hair of stone formers. PMID:20024629

S?ojewski, Marcin; Czerny, Bogus?aw; Safranow, Krzysztof; Jakubowska, Katarzyna; Olszewska, Maria; Pawlik, Andrzej; Go??b, Adam; Dro?dzik, Marek; Chlubek, Dariusz; Sikorski, Andrzej

2009-12-19

342

Influence of the Niobium or Fluorine Dopant Concentration on the Properties of Mn-Doped Lead Zirconate Titanate Ceramics  

NASA Astrophysics Data System (ADS)

In this paper, we report on the effect of donor addition (Nb5+ or F-) on the electrical and piezoelectric properties and crystallographic characteristics of Mn-doped lead zirconate titanate (PZT) ceramics. Samples were prepared chemically by coprecipitation of oxalates and hydroxides. The niobium ion was incorporated in the B site whereas the fluorine ion was introduced in the anionic site. Structural analysis (XRD) and measurement of electrical properties were carried out. Electron spin resonance was used to determined the valency states of manganese in PZT ceramics. From the experimental results, the F-O substitution decreases the amount of oxygen vacancies in the Mn-doped PZT, and the valency states remain unchanged. However, a small number of oxygen vacancies may exist in PZT doped with 1 at.% manganese and 2 at.% fluorine. In the (Mn,Nb) co-doping case, the valency states vary from 4+ to 2+ and the number of oxygen vacancies is lower or even almost equal to zero. Thus the electroneutrality is achieved by lead vacancies.

Boucher, Eric; Guiffard, Benoit; Lebrun, Laurent; Guyomar, Daniel

2004-08-01

343

Electrochemical detection of viable bacteria in urine and antibiotic selection.  

PubMed

An electrode system consisting of a basal-plane pyrolytic graphite (BPG) electrode and a porous nitrocellulose membrane filter to trap bacteria was used for the detection of bacteria in urine. The peak current of a cyclic voltammogram increased with increasing initial cell concentration of Escherichia coli in urine. Urine containing from 5 x 10(2) to 5 x 10(5) cells ml-1 was measured with this system. The susceptibility of bacteria to various antibiotics was also determined from the peak current. The minimum inhibitory concentration values obtained by the electrochemical method were in good agreement with those obtained by the conventional method. PMID:1756000

Nakamura, N; Shigematsu, A; Matsunaga, T

1991-01-01

344

Malondialdehyde in exhaled breath condensate and urine as a biomarker of air pollution induced oxidative stress.  

PubMed

Underlying mechanisms by which air pollutants adversely affect human health remain poorly understood. Oxidative stress has been considered as a potential mechanism that may promote lipid peroxidation by reactive oxygen species, leading to the formation of malondialdehyde (MDA) that is excreted in biofluids (e.g., urine and exhaled breath condensate (EBC)). A panel study was conducted to examine whether concentrations of MDA in EBC and urine were associated, respectively, with changes in air pollution levels brought by the Beijing Olympic air pollution control measures. EBC and urine samples from 125 healthy adults were collected twice in each of the pre-, during-, and post-Olympic periods. Period-specific means of MDA and changes in MDA levels associated with increases in 24-h average pollutant concentrations were estimated using linear mixed-effects models. From the pre- to the during-Olympic period, when concentrations of most pollutants decreased, EBC MDA and urinary MDA significantly decreased by 24% (P<0.0001) and 28% (P=0.0002), respectively. From the during-Olympic to the post-Olympic period, when concentrations of most pollutants increased, EBC MDA and urinary MDA increased by 28% (P=0.094) and 55% (P=0.046), respectively. Furthermore, the largest increases in EBC MDA associated with one interquartile range (IQR) increases in all pollutants but ozone ranged from 10% (95% CI: 2%, 18%) to 19% (95% CI: 14%, 25%). The largest increases in urinary MDA associated with IQR increases in pollutant concentration ranged from 9% (95%: 0.3%, 19%) to 15% (95% CI: 3%, 28%). These findings support the utility of EBC MDA as a biomarker of oxidative stress in the respiratory tract and urinary MDA as a biomarker of systemic oxidative stress in relation to air pollution exposure in healthy young adults. Both EBC and urine samples can be collected noninvasively in the general population. PMID:23321859

Gong, Jicheng; Zhu, Tong; Kipen, Howard; Wang, Guangfa; Hu, Min; Ohman-Strickland, Pamela; Lu, Shou-En; Zhang, Lin; Wang, Yuedan; Zhu, Ping; Rich, David Q; Diehl, Scott R; Huang, Wei; Zhang, Junfeng Jim

2013-01-16

345

Presence of endogenous prednisolone in human urine.  

PubMed

The possibility of an endogenous presence of the glucocorticoid prednisolone has already been demonstrated in bovine and horse urine, with the aim of clarifying its origin in this matrix, which is used by official agencies for the control of illicit treatments. From this point of view, the endogenous nature of prednisolone could be a major topic in doping control of both amateur and professional human athletes. A study was therefore made on 34 human volunteers (13 males and 21 females; aged 22-62) to detect the presence of prednisolone in their urine by HPLC-MS(3). One of the volunteers underwent vernal allergy treatment with betamethasone for two subsequent years. An investigation was carried out with the aim of verifying if the suppression, and the circadian rhythm, of cortisol urinary levels could also apply to prednisolone. The results of the study show that prednisolone was present in the urine of all 34 volunteers, with a concentration very close to 100-times lower that of cortisol, with no dependence on gender. The same ratio (1/100) was observed in the prednisolone and cortisol levels detected during the 24h together with the suppression of prednisolone by betamethasone treatment. These data demonstrate the endogenous nature of low concentrations of prednisolone in human urine, and motivate further studies about the biosynthetic pathways of this corticosteroid and its relationship with stress in humans, as already described in cows. PMID:23182764

Fidani, Marco; Gamberini, Maria C; Pompa, Giuseppe; Mungiguerra, Francesca; Casati, Alessio; Arioli, Francesco

2012-11-23

346

A novel in situ method for sampling urban soil dust: particle size distribution, trace metal concentrations, and stable lead isotopes.  

PubMed

In this study, a novel in situ sampling method was utilized to investigate the concentrations of trace metals and Pb isotope compositions among different particle size fractions in soil dust, bulk surface soil, and corresponding road dust samples collected within an urban environment. The aim of the current study was to evaluate the feasibility of using soil dust samples to determine trace metal contamination and potential risks in urban areas in comparison with related bulk surface soil and road dust. The results of total metal loadings and Pb isotope ratios revealed that soil dust is more sensitive than bulk surface soil to anthropogenic contamination in urban areas. The new in situ method is effective at collecting different particle size fractions of soil dust from the surface of urban soils, and that soil dust is a critical indicator of anthropogenic contamination and potential human exposure in urban settings. PMID:23466731

Bi, Xiangyang; Liang, Siyuan; Li, Xiangdong

2013-03-06

347

Elevated atmospheric CO2 concentration leads to increased whole-plant isoprene emission in hybrid aspen (Populus tremula × Populus tremuloides).  

PubMed

Effects of elevated atmospheric [CO2] on plant isoprene emissions are controversial. Relying on leaf-scale measurements, most models simulating isoprene emissions in future higher [CO2] atmospheres suggest reduced emission fluxes. However, combined effects of elevated [CO2] on leaf area growth, net assimilation and isoprene emission rates have rarely been studied on the canopy scale, but stimulation of leaf area growth may largely compensate for possible [CO2] inhibition reported at the leaf scale. This study tests the hypothesis that stimulated leaf area growth leads to increased canopy isoprene emission rates. We studied the dynamics of canopy growth, and net assimilation and isoprene emission rates in hybrid aspen (Populus tremula × Populus tremuloides) grown under 380 and 780 ?mol mol(-1) [CO2]. A theoretical framework based on the Chapman-Richards function to model canopy growth and numerically compare the growth dynamics among ambient and elevated atmospheric [CO2]-grown plants was developed. Plants grown under elevated [CO2] had higher C : N ratio, and greater total leaf area, and canopy net assimilation and isoprene emission rates. During ontogeny, these key canopy characteristics developed faster and stabilized earlier under elevated [CO2]. However, on a leaf area basis, foliage physiological traits remained in a transient state over the whole experiment. These results demonstrate that canopy-scale dynamics importantly complements the leaf-scale processes, and that isoprene emissions may actually increase under higher [CO2] as a result of enhanced leaf area production. PMID:23442171

Sun, Zhihong; Niinemets, Ülo; Hüve, Katja; Rasulov, Bahtijor; Noe, Steffen M

2013-02-27

348

Application of electrolysis for detoxification of an antineoplastic in urine.  

PubMed

Antineoplastics in excreta from patients have been considered to be one of the origins of cytotoxic, carcinogenic, teratogenic, and mutagenic contaminants in surface water. Recent studies have demonstrated that antineoplastics in clinical wastewater can be detoxified by electrolysis. In this study, to develop a method for the detoxification of antineoplastics in excreta, methotrexate solution in the presence of human urine was electrolyzed and evaluated. We found that urine inhibits detoxification by electrolysis; however, this inhibition decreased by diluting urine. In urine samples, the concentrations of active chlorine generated by anodic oxidation from 0.9% NaCl solution for inactivation of antineoplastics increased in dilution-dependent and time-dependent manner. These results indicate that electrolysis with platinum-based iridium oxide composite electrode is a possible method for the detoxification of a certain antineoplastic in urine. PMID:22154144

Kobayashi, Toyohide; Hirose, Jun; Sano, Kouichi; Kato, Ryuji; Ijiri, Yoshio; Takiuchi, Hiroya; Tanaka, Kazuhiko; Goto, Emi; Tamai, Hiroshi; Nakano, Takashi

2011-12-09

349

Excretion of Transmissible Spongiform Encephalopathy Infectivity in Urine  

PubMed Central

The route of transmission of most naturally acquired transmissible spongiform encephalopathy (TSE) infections remains speculative. To investigate urine as a potential source of TSE exposure, we used a sensitive method for detection and quantitation of TSE infectivity. Pooled urine collected from 22 hamsters showing clinical signs of 263K scrapie contained 3.8 ± 0.9 infectious doses/mL of infectivity. Titration of homogenates of kidneys and urinary bladders from the same animals gave concentrations 20,000-fold greater. Histologic and immunohistochemical examination of these same tissues showed no indications of inflammatory or other pathologic changes except for occasional deposits of disease-associated prion protein in kidneys. Although the source of TSE infectivity in urine remains unresolved, these results establish that TSE infectivity is excreted in urine and may thereby play a role in the horizontal transmission of natural TSEs. The results also indicate potential risk for TSE transmission from human urine–derived hormones and other medicines.

Gregori, Luisa; Kovacs, Gabor G.; Alexeeva, Irina; Budka, Herbert

2008-01-01

350

Determination of lead and cadmium concentration limits in agricultural soil and municipal solid waste compost through an approach of zero tolerance to food contamination.  

PubMed

Cadmium and lead are important environmental pollutants with high toxicity to animals and human. Soils, though have considerable metal immobilizing capability, can contaminate food chain via plants grown upon them when their built-up occurs to a large extent. Present experiment was carried out with the objective of quantifying the limits of Pb and Cd loading in soil for the purpose of preventing food chain contamination beyond background concentration levels. Two separate sets of pot experiment were carried out for these two heavy metals with graded levels of application doses of Pb at 0.4-150 mg/kg and Cd at 0.02-20 mg/kg to an acidic light textured alluvial soil. Spinach crop was grown for 50 days on these treated soils after a stabilization period of 2 months. Upper limit of background concentration levels (C(ul)) of these metals were calculated through statistical approach from the heavy metals concentration values in leaves of spinach crop grown in farmers' fields. Lead and Cd concentration limits in soil were calculated by dividing C(ul) with uptake response slope obtained from the pot experiment. Cumulative loading limits (concentration limits in soil minus contents in uncontaminated soil) for the experimental soil were estimated to be 170 kg Pb/ha and 0.8 kg Cd/ha. Based on certain assumptions on application rate and computed cumulative loading limit values, maximum permissible Pb and Cd concentration values in municipal solid waste (MSW) compost were proposed as 170 mg Pb/kg and 0.8 mg Cd/kg, respectively. In view of these limiting values, about 56% and 47% of the MSW compost samples from different cities are found to contain Pb and Cd in the safe range. PMID:19662502

Saha, Jayanta Kumar; Panwar, N R; Singh, M V

2009-08-07

351

[The human placenta's lead level as a parameter of the ecological lead exposure. Its validity in comparison to the lead level in blood, the activity of the delta-aminolevulinic acid dehydratase and the concentration of the free erythrocyte porphyrins of newborns and their mothers (author's transl)].  

PubMed

In order to estimate the ecological exposure of lead, placenta- and blood-investigations were made at four collectives from variously industrialized regions (Ruhrregion, Middle Frankonia Centre, Bavarian Forest). 148 normal births and 19 premature births (in each case mothers and newborns) were listed as well as twelve abortions. We investigated the lead-level in blood, the activity of delta-aminolaevulinic acid dehydratase (ALA-D) the concentration of free erythrocyte porphyrine (FEP) and the placentas' lead concentration. Though in the Ruhrregion (Dortmund) significantly higher lead levels in blood were found compared to the Bavarian Forest, the results together, were in the normal range, less than 35 mug%. In an average the mothers' lead level in blood was around 1.4 times (ca. 5 mug%) above that of their newborns; analysing this statistically, highly significant correlations were found. However for the ALA-D activity and the FEP-results no direct dependence of the lead levels in blood could be found. In the placentas mean lead concentrations between 1.94 mug and 2.23 mug per gram dry-weight (30.6 mug-38.9 mug/100 g wet-weight) were gained. In the contrary to the measured results of lead in blood the average placentas' lead level of the most and least industrialized regions were almost identical. A correlation between the mothers' respectively their children's lead levels in blood and the placental lead concentrations could not be proved. No relation could be found between the results and the gestation ages. As final results: 1. The placenta is no ideal investigation object concerning the environment's lead exposure. 2. It has no special barriere - or depot - function in lead metabolism. 3. In order to estimate the environment's lead exposure the determination of the lead level in blood will also be in future the optimal method. This investigation is of special value because of its validity of the results and the practicability of winning the samples compared to other parameters and biological materials. PMID:983547

Engelhardt, E; Schaller, K H; Schiele, R; Valentin, H

1976-08-01

352

Determination of 226Ra in urine samples by alpha spectrometry.  

PubMed

A radiation protection system to assess the internal contamination of workers during decontamination activities in an abounded fertilizer industry in the region of Attika, Greece, has been implemented. This system concerns, among other radionuclides, 226Ra. Because of the low 226Ra activities in urine, alpha spectrometry was used as the determination method after radiochemical separation. Radium was co precipitated with lead sulphate and purified using anion and cation exchange techniques. The source for the alpha spectrometric measurement was prepared by the electrodeposition of radium, from an aqueous/ethanol solution, onto stainless steel. The tracer used was 229Th. The chemical yield and the activity concentration were calculated via its daughter radionuclide 217At. Using the time-evolution formulas to calculate the 217At growth from its parent radionuclide 225Ra, a computer software was developed. This software was incorporated in a database, which automatically calculates and stores the results. PMID:17827131

Kehagia, K; Potiriadis, C; Bratakos, S; Koukouliou, V; Drikos, G

2007-09-07

353

A metabolomic approach in an experimental model of hypoxia-reoxygenation in newborn piglets: urine predicts outcome.  

PubMed

Perinatal asphyxia is one of the leading causes of morbidity and mortality in the neonatal period. Response to oxygen treatment is unpredictable and the optimum concentration of oxygen in neonatal resuscitation is still a matter of debate among neonatologists. A metabolomic approach was used to characterize the metabolic profiles of newborn hypoxic-reoxygenated piglets. Urine samples were collected from newborn piglets (n?=?40) undergoing hypoxia followed by resuscitation at different oxygen concentrations (ranging from 18% to 100%) and analyzed by ¹H NMR spectroscopy. Despite reoxygenation 7 piglets, out of 10 which became asystolic, did not respond to resuscitation. Profiles of the ¹H NMR spectra were submitted to unsupervised (principal component analysis) and supervised (partial least squares-discriminant analysis) multivariate analysis. The supervised analyses showed differences in the metabolic profile of the urine collected before the induction of hypoxia between survivors and deaths. Metabolic variations were observed in the urine of piglets treated with different oxygen concentrations comparing T0 (basal value) and end of the experiment (resuscitation). Some of the individual metabolites discriminating between these groups were urea, creatinine, malonate, methylguanidine, hydroxyisobutyric acid. The metabolomic approach appears a promising tool for investigating newborn hypoxia over time, for monitoring the response to the treatment with different oxygen concentrations, and might lead to a tailored management of the disorder. PMID:20873980

Atzori, Luigi; Xanthos, Theodoros; Barberini, Luigi; Antonucci, Roberto; Murgia, Federica; Lussu, Milena; Aroni, Filippia; Varsami, Marianna; Papalois, Apostolos; Lai, Adolfo; D'Aloja, Ernesto; Iacovidou, Nicoletta; Fanos, Vassilios

2010-10-01

354

Urease-induced crystallizations of calcium phosphate and magnesium ammonium phosphate in synthetic urine and human urine.  

PubMed

An aggregometer technique was used to study urease-induced crystallizations in synthetic urine and human urine from healthy subjects and patients with chronic spinal cord injuries. The two different phases of crystallization, calcium phosphate and magnesium ammonium phosphate, were easily evaluated with a single assay using this technique. The crystallization of calcium phosphate and magnesium ammonium phosphate varied markedly among the different urine specimens after incubation with urease. The turbidity curves from human urine were divided into four patterns. We assumed that the variations in the patterns of the turbidity curves appeared to be mainly due to differences in the composition of the urine and in the original pH, and that the calcium and magnesium concentrations were very important in the urinary constituents. PMID:9286035

Ebisuno, S; Komura, T; Yamagiwa, K; Ohkawa, T

1997-01-01

355

NEW COLUMN SEPARATION METHOD FOR EMERGENCY URINE SAMPLES  

SciTech Connect

The Savannah River Site Environmental Bioassay Lab participated in the 2007 NRIP Emergency Response program administered by the National Institute for Standards and Technology (NIST) in May, 2007. A new rapid column separation method was applied directly to the NRIP 2007 emergency urine samples, with only minimal sample preparation to reduce preparation time. Calcium phosphate precipitation, previously used to pre-concentrate actinides and Sr-90 in NRIP 2006 urine and water samples, was not used for the NRIP 2007 urine samples. Instead, the raw urine was acidified and passed directly through the stacked resin columns (TEVA+TRU+SR Resins) to separate the actinides and strontium from the NRIP urine samples more quickly. This improvement reduced sample preparation time for the NRIP 2007 emergency urine analyses significantly. This approach works well for small volume urine samples expected during an emergency response event. Based on initial feedback from NIST, the SRS Environmental Bioassay Lab had the most rapid analysis times for actinides and strontium-90 analyses for NRIP 2007 urine samples.

Maxwell, S; Brian Culligan, B

2007-08-28

356

Sheep-urine-induced changes in soil microbial community structure.  

PubMed

Soil microbial communities play an important role in nutrient cycling and nutrient availability, especially in unimproved soils. In grazed pastures, sheep urine causes local changes in nutrient concentration which may be a source of heterogeneity in microbial community structure. In the present study, we investigated the effects of synthetic urine on soil microbial community structure, using physiological (community level physiological profiling, CLPP), biochemical (phospholipid fatty acid analysis, PLFA) and molecular (denaturing gradient gel electrophoresis, DGGE) fingerprinting methods. PLFA data suggested that synthetic urine treatment had no significant effect on total microbial (total PLFA), total bacterial or fungal biomass; however, significant changes in microbial community structure were observed with both PLFA and DGGE data. PLFA data suggested that synthetic urine induced a shift towards communities with higher concentrations of branched fatty acids. DGGE banding patterns derived from control and treated soils differed, due to a higher proportion of DNA sequences migrating only to the upper regions of the gel in synthetic urine-treated samples. The shifts in community structure measured by PLFA and DGGE were significantly correlated with one another, suggesting that both datasets reflected the same changes in microbial communities. Synthetic urine treatment preferentially stimulated the use of rhizosphere-C in sole-carbon-source utilisation profiles. The changes caused by synthetic urine addition accounted for only 10-15% of the total variability in community structure, suggesting that overall microbial community structure was reasonably stable and that changes were confined to a small proportion of the communities. PMID:16629760

Nunan, Naoise; Singh, Brajesh; Reid, Eileen; Ord, Brian; Papert, Artemis; Squires, Julie; Prosser, Jim I; Wheatley, Ron E; McNicol, Jim; Millard, Peter

2006-05-01

357

Thermal lens study of thermo-optical properties and concentration quenching of Er{sup 3+}-doped lead pyrophosphate-based glasses  

SciTech Connect

In this work, we have used the thermal lens technique combined with conventional spectroscopy to characterize the thermo-optical properties of Er{sup 3+}-doped lead pyrophosphate-based glasses. More precisely, we have investigated and quantified experimentally the fluorescence quantum efficiencies of the Er{sup 3+} levels, and we describe the role of concentration quenching effects. The fluorescence quantum efficiency of the {sup 4}I{sub 13/2} level is very high when compared to other phosphate glasses, while that of the green-coupled levels is very small. Other important photonic materials parameters, such as the thermal diffusivity and temperature coefficient of the optical path length change, were obtained and compared with those of other glass systems. The cumulative results obtained here for the Er-doped lead pyrophosphate glass show that this material is a good candidate for photonic applications with a characteristic Er{sup 3+} infrared emission around 1550 nm.

Santos, C. C. [Departamento de Fisica, CCET, Universidade Federal do Maranhao, 65085-580 Sao Luis-MA (Brazil); Rocha, U.; Vermelho, M. V. D.; Jacinto, C. [Grupo de Fotonica e Fluidos Complexos, Instituto de Fisica, Universidade Federal de Alagoas, 57072-970 Maceio, AL (Brazil); Guedes, I. [Departamento de Fisica, Universidade Federal do Ceara, Campus do PICI, Caixa Postal 6030, 60455-760 Fortaleza, CE (Brazil); Boatner, L. A. [ORNL Center for Radiation Detection Materials and Systems and ORNL Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6044 (United States)

2012-06-15

358

National contaminant biomonitoring program: Concentrations of arsenic, cadmium, copper, lead, mercury, selenium, and zinc in U.S. Freshwater Fish, 1976–1984  

Microsoft Academic Search

From late 1984 to early 1985, the U.S. Fish and Wildlife Service collected a total of 315 composite samples of whole fish\\u000a from 109 stations nationwide, which were analyzed for arsenic, cadmium, copper, lead, mercury, selenium, and zinc. Geometric\\u000a mean, maximum, and 85th percentile concentrations (?g\\/g wet weight) for 1984 samples were as follows: arsenic-0.14, 1.5, 0.27;\\u000a cadmium-0.03, 0.22, 0.05;

Christopher J. Schmitt; William G. Brumbaugh

1990-01-01

359

Nitrification of human urine for its stabilization and nutrient recycling.  

PubMed

Nitrification of human urine performed for its stabilization, and culture of Spirulina platensis in the nitrified human urine were investigated for nutrient recovery. With daily adjusting to pH 8 and keeping high dissolved oxygen concentration, mean 95.0% of NH(4)-N in human urine can be finally stabilized and oxidized to NO(3)-N. Furthermore, this nitrified human urine seems to be an ideal culture medium for S. platensis. Without pH adjustment, only about 50.0% NH(4)-N could be converted, i.e. NH(4)NO(3) would be formed. Under low dissolved oxygen concentration, mainly short nitrification (from NH(4)-N to NO(2)-N) occurred. PMID:18194861

Feng, Daolun; Wu, Zucheng; Xu, Shihong

2008-01-14

360

Citrate and urease-induced crystallization in synthetic and human urine.  

PubMed

The effects of citrate on the different phases of urease-induced crystallization were studied using Coulter counter techniques and optical microscopy. Citrate increased urine pH and markedly delayed the initiation of the crystallization (nucleation) in both human and synthetic urine. In synthetic urine, particle aggregation and especially particle growth were delayed and inhibited by citrate. In human urine, aggregation was distinctly inhibited by citrate. It appears that the susceptibility of urine to form crystals in the presence of urease activity is influenced by its citrate concentration. PMID:8503146

Wang, Y H; Grenabo, L; Hedelin, H; McLean, R J; Nickel, J C; Pettersson, S

1993-03-01

361

Steroid extraction process from urine sources  

US Patent & Trademark Office Database

A process in which urine is optionally filtered to remove solid extraneous matter and optionally treated so as to reduce the phenolic content of the urine to give and the resulting fluid is then subjected to a solid extraction of the major concentration steroids content therefrom by a first suitable resin (to yield a first resin laden with major concentration steroids and a minor concentration steroid laden first liquid remainder). The minor concentration steroid liquid remainder is subjected to a solid extraction of the minor concentration steroid content therefrom by a second suitable resin (to yield a second resin laden with minor concentration steroids and a second liquid remainder). The first and second resins laden with their respective steroids are then eluted and the eluates are collected separately and optionally subjected to further purification and chromatographic separations, with each resulting separate collection being analyzed for the steroid content thereof. The separate analyzed materials are dried and stored for recombination in an appropriate manner to meet a desired profile. The ultimate product has very nearly the same steroid components and concentrations from batch to batch.

2013-01-08

362

Alkylresorcinol Metabolite Concentrations in Spot Urine Samples Correlated with Whole Grain and Cereal Fiber Intake but Showed Low to Modest Reproducibility over One to Three Years in U.S. Women123  

PubMed Central

Two alkylresorcinol (AR) metabolites, 3, 5-dihydroxybenzoic acid (DHBA) and 3-(3,5-dihydroxyphenyl)-1-propanoic acid (DHPPA), in urine have been suggested as biomarkers of whole grain (WG) and cereal fiber intake but the long-term reproducibility and correlation with habitual intake has not been determined. Therefore, we evaluated the long-term reproducibility of AR metabolites in spot urine samples and investigated their correlation with habitual WG and cereal fiber intake in U.S. women. AR metabolites were analyzed in 104 women participating in the Nurses’ Health Study II and WG and fiber intakes were assessed using a FFQ. Long-term reproducibility was assessed by calculating the intra-class correlation coefficients (ICC) using samples taken 1–3 y (mean 1.8 y) apart. The observed Spearman correlation coefficients (rs) and rs adjusted for within-participant variation in the biomarker were calculated between WG and fiber intake and biomarkers. The long-term reproducibility was poor for DHBA [ICC = 0.17 (95% CI: 0.05, 0.43)] and modest for DHPPA [ICC = 0.31 (95% CI: 0.17, 0.51)]. The correlation between WG intake in 1995 and DHPPA measured 2 y later was 0.37 (P < 0.0001); the adjusted correlation was 0.60 (95% CI: 0.37, 0.76). Cereal fiber and WG intake were similarly correlated to the biomarkers. DHPPA in spot urine samples reflected WG intake despite relatively low intake of food sources of AR. The poor to modest reproducibility may limit the use of single measurements of these biomarkers in cohort studies in the US, where WG intake is relatively low and has changed over time. But DHPPA in repeated samples may be useful for validating WG intake and assessing compliance in WG intervention studies.

Landberg, Rikard; Townsend, Mary K.; Neelakantan, Nithya; Sun, Qi; Sampson, Laura; Spiegelman, Donna; van Dam, Rob M.

2012-01-01

363

Nitrification and autotrophic denitrification of source-separated urine  

Microsoft Academic Search

In laboratory experiments, source-separated urine was stabilised with nitrification and denitrified via nitritation and anaerobic ammonium oxidation. The highest total ammonia concentration in the influent was 7,300 gN\\/m3, the maximum pH 9.2. In a moving bed biofilm reactor (MBBR) with Kaldnes® biofilm carriers, we stabilised urine as a 1:1 ammonium nitrate solution. The maximum nitrification rate was 380 gN\\/m3\\/d corresponding

K. M. Udert; C. Fux; M. Münster; T. A. Larsen; H. Siegrist; W. Gujer

2003-01-01

364

Some historical aspects of urinals and urine receptacles.  

PubMed

In the history of mankind the first receptacles for urine were made and employed for diagnostic purposes and developed over centuries to a sophisticated matula. In ancient Greek and Roman history, chamber pots existed and urine was collected to bleach sheets, but it was only in the late medieval and renaissance times that a real urine receptacle or urinal for daily use was developed. We give a short description of the materials used, including clay, pewter, copper, and silver, but more sophisticated receptacles made of china, such as the bourdaloue, and of glass, such as the Kuttrolf, were also developed for use during long church ceremonies. Less known are the wooden "pipes" from Turkestan, used to keep babies dry. In the long history of mankind, urinals sometimes became very original objects. PMID:10418087

Mattelaer, J J

1999-06-01

365

Elevated urine uranium excretion by soldiers with retained uranium shrapnel.  

PubMed

The use of depleted uranium in munitions has given rise to a new exposure route for this chemically and radioactively hazardous metal. A cohort of U.S. soldiers wounded while on or in vehicles struck by depleted uranium penetrators during the Persian Gulf War was identified. Thirty-three members of this cohort were clinically evaluated, with particular attention to renal abnormalities, approximately 3 y after their injury. The presence of retained shrapnel was identified by x ray, and urine uranium concentrations were measured on two occasions. The absorption of uranium from embedded shrapnel was strongly suggested by measurements of urine uranium excretion at two time intervals: one in 1993/1994 and one in 1995. Mean urine uranium excretion was significantly higher in soldiers with retained shrapnel compared to those without shrapnel at both time points (4.47 vs. 0.03 microg g(-1) creatinine in 1993/1994 and 6.40 vs. 0.01 microg g(-1) creatinine in 1995, respectively). Urine uranium concentrations measured in 1995 were consistent with those measured in 1994/1993, with a correlation coefficient of 0.9. Spot urine measurements of uranium excretion were also well correlated with 24-h urine collections (r = 0.95), indicating that spot urine samples can be reliably used to monitor depleted uranium excretion in the surveillance program for this cohort of soldiers. The presence of uranium in the urine can be used to determine the rate at which embedded depleted uranium fragments are releasing biologically active uranium ions. No evidence of a relationship between urine uranium excretion and renal function could be demonstrated. Evaluation of this cohort continues. PMID:10524504

Hooper, F J; Squibb, K S; Siegel, E L; McPhaul, K; Keogh, J P

1999-11-01

366

delta-Aminolevulinic acid dehydratase activity, urinary delta-aminolevulinic acid concentration and zinc protoporphyrin level among people with low level of lead exposure.  

PubMed

To evaluate the relationship of delta-aminolevulinic acid dehydratase (ALAD) activity, urinary delta-aminolevulinic acid (ALAU) level and blood zinc protoporphyrin (ZPP) concentration to low blood lead (PbB) levels, these biomarkers were determined for all subjects enrolled from a rural area of southeast China where people had low levels of exposure to lead. The mean values of PbB, ALAD, ALAU and ZPP were 67.11 microg/L (SD: 1.654, range: 10.90-514.04), 339.66 nmol ml(-1)h(-1) (1.419, 78.33-793.13), 20.64 microg/L (1.603, 2.00-326.00), and 0.14 micromol/L (3.437, 0.01-2.26), respectively. ALAD was inversely associated with low levels of PbB. ZPP was inversely related to low levels of PbB but positively related to relatively higher levels of PbB. Alcohol drinking contributed to low ALAD in men. Women had higher ZPP than men. ALAU had no significant association with PbB. In conclusion, ALAD possibly has a non-linear relation with low to moderate levels of PbB. At moderate levels of PbB, ZPP increases with increasing levels of PbB. ALAU is not suitable as an indicator for low levels of lead exposure. PMID:19733117

Wang, Qi; Zhao, Huan-hu; Chen, Jian-wei; Hao, Qiao-ling; Gu, Kang-ding; Zhu, Ye-xiang; Zhou, Yi-kai; Ye, Lin-xiang

2009-09-04

367

Levels of lead, cadmium, copper, iron, and zinc in deciduous teeth of children living in Irbid, Jordan by ICP-OES: some factors affecting their concentrations.  

PubMed

The aim of this study was to measure the concentrations of lead (Pb), cadmium (Cd), copper (Cu), iron (Fe), and zinc (Zn) in deciduous teeth from children living in Jordan and to investigate the affecting factors. Deciduous teeth samples (n = 320, without fillings) were collected from 5- to 12-year-old children and analyzed for Pb, Cd, Cu, Fe, and Zn using inductively coupled plasma-optical emission spectrometry. A questionnaire was used to gather information on each child, such as sex, age, tooth type (incisors, canines, and molars), tooth position within the mouth (upper or lower jaw), caries status, presence of amalgam fillings inside the mouth, type of drinking water (tap water, home purified water, and plant purified water), and zone of residence (close to or far from heavy traffic roads). The mean concentrations of Pb, Cd, Cu, Fe, and Zn were 30.26, 0.55, 6.23, 34.72, and 128.21 ?g/g, respectively. Our results indicate that there is a clear relation between the concentrations of the metals analyzed in this study and tooth type, tooth position within the mouth, caries status, presence of amalgam fillings inside the mouth, and type of drinking water. No significant differences in the concentrations of the five metals analyzed were observed due to sex. Our results also show that no significant difference among Pb, Cd, Cu, Fe, and Zn concentrations and age among the ages of 5-6, 7-8, 9-10, and 11-12, except for Pb, which decreases at age 11-12. PMID:22851195

Alomary, A; Al-Momani, I F; Obeidat, S M; Massadeh, A M

2012-08-01

368

Sorption of trace metals on human hair and application for cadmium and lead pre-concentration with flame atomic absorption determination.  

PubMed

Human hair shavings were characterized as a sorbent for trace metals. At pH 7.0 metal sorption follows the order Pb(II)>Cd(II)>Cr(VI)>Fe(III)>Cu(II)>Ni(II)>Mn(VI). Metal recovery is quantitative for Pb and Cd after 30 min of equilibration. Recovery of other metals is less quantitative and varies with pH. For example, while Cu is best recovered at pH 5, Ni and Mn are sorbed optimally in the basic pH region. Sorbed metals can be washed off the sorbent with 0.5 mol L(-1) strong mineral acids or more completely with 0.1 mol L(-1) ethylenediaminetetraacetic acid (EDTA). Typical sorption isotherms were obtained for Cd and Pb with sorption capacities of 39 and 26 micromol g(-1), respectively. Hair sorbent was used for 40-fold pre-concentration of Cd and Pb from treated wastewater samples followed by flame atomic absorption spectroscopic (FAAS) determination. Comparison of the data obtained for lead and cadmium by the proposed pre-concentration method with that by graphite furnace atomic absorption spectroscopy (GFAAS) showed 79 to 86% recovery and comparable analytical precision. Common cations and anions at the levels normally present in natural water do not interfere in the proposed pre-concentration-FAAS method. PMID:12589512

Sweileh, Jamal A

2003-01-04

369

Urine citrate and renal stone disease.  

PubMed Central

Calcium stone disease is attributable to supersaturation of the urine with calcium and other salts, the presence of substances that promote crystallization and a deficiency of inhibitors of crystallization. Citrate is a potent inhibitor of calcium oxalate and calcium phosphate stone formation whose excretion is diminished in some patients with stone disease owing to idiopathic causes or secondary factors such as bowel disease and use of thiazides. The pH within the proximal tubule cells is an important determinant of citrate excretion. Multivariate analysis has shown that the urine concentrations of calcium and citrate are the most important factors in stone formation. In uncontrolled studies potassium citrate, which increases urinary citrate excretion, appears to be promising as a therapeutic agent for patients with stone disease and hypocitraturia refractory to other treatment. On the other hand, there are potential drawbacks to sodium alkali therapy, such as the precipitation of calcium phosphates.

Goldberg, H; Grass, L; Vogl, R; Rapoport, A; Oreopoulos, D G

1989-01-01

370

A nitrogen balance experiment using simulated urine samples.  

PubMed

We describe an undergraduate laboratory experiment that combines the advantages of problem-based learning with the need for biochemistry students to become proficient in practical laboratory skills. It also avoids the need to obtain ethical approval for recruiting volunteers and eliminates any possible biosafety issues with the handling and disposal of large amounts of urine. Simulated human urine samples are prepared that contain urea, uric acid, and creatinine at concentrations that represent the levels expected in 2 liters of urine collected over 24 h from subjects on various protein diets or during different physiological states. The students measure the nitrogen-containing compounds in the "urine samples" using specific colorimetric assays and use the data they generate to derive knowledge about nitrogen balance and the excretory metabolism of amino acids. PMID:21638698

Sadighi, Mehri; Reichman, Nurit; Wilson, Kaye; Carne, Alan; Thompson, Mary P

2006-07-01

371

Fluoride in the urine, hair, and nails of phosphate fertiliser workers.  

PubMed Central

The fluoride content in the urine, hair, and nails of 106 workers employed in a phosphate fertiliser plant was significantly raised above the control level. Positive correlations were found between the group means for concentrations of fluorides in urine and hair (r = 0.77), urine and nails (r = 0.99), and hair and nails (r = 0.70). Individual values in the whole population gave significant correlations between concentrations in urine and nails (r = 0.73). The obtained results indicate that the fluoride content in hair and nails may be used as an indicator of occupational exposure to fluorides.

Czarnowski, W; Krechniak, J

1990-01-01

372

Use of human urine in phytoplankton production as a tool for ecological sanitation.  

PubMed

Measurements of primary productivity of phytoplankton and enumeration of the counts of coliform and heterotrophic bacteria (HB) were made in the water of 12 experimental tanks used for 3 treatments and control in triplicate as follows: (a) fresh human urine (0.02%), (b) stored human urine (0.02%), (c) mixed urine of fresh and stored human urine (0.02%) and (d) control without input of urine. The gross primary productivity of phytoplankton was highest in the stored urine treated tanks (508 mg C m(-2) h(-1)) followed by fresh urine (353 mg C m(-2) h(-1)), mixed urine (303 mg C m(-2) h(-1)) and control (215 mg C m(-2) h(-1)). Similar was the response of net primary production of phytoplankton. The mean count of HB observed in stored urine fed tanks was significantly higher (59-184%) than the remaining urine fed treatments. The mean count of Escherichia coli did not differ from urine treated tanks to control implying the good quality of water. The concentration of dissolved oxygen of water (7.6 to 12.8 mg L(-1)) in these tanks remained satisfactory for aquaculture. The mean concentration of ammonium-N observed in fresh urine treated tanks was more than 10 times higher than the remaining treatments employed. In contrast, the level of phosphate and electrical conductivity in the stored urine treated tanks were significantly higher than the remaining treatments. It is proposed that stored urine with a significantly reduced load of E. coli might be an effective low cost liquid fertilizer for algal biomass production. PMID:22466579

Jana, B B; Rana, S; Bag, S K

2012-01-01

373

Determination of trace element concentrations and stable lead, uranium and thorium isotope ratios by quadrupole-ICP-MS in NORM and NORM-polluted sample leachates.  

PubMed

This work focuses on the monitoring of the potential pollution in scenarios that involve NORM-related industrial activities (environmental or in-door scenarios). The objective was to develop a method to determine extent and origin of the contamination, suitable for monitoring (i.e. simple, fast and economical) and avoiding the use of too many different instruments. It is presented a radiochemical method that allows the determination of trace element concentrations and 206Pb/207Pb/208Pb, 238U/234U and 232Th/230Th isotope ratios using a single sample aliquot and a single instrument (ICP-QMS). Eichrom UTEVA® extraction chromatography minicolumns were used to separate uranium and thorium in sample leachates. Independent ICP-MS determinations of uranium and thorium isotope ratios were carried out afterwards. Previously a small aliquot of the leachate was used for the determination of trace element concentrations and lead isotope ratios. Several radiochemical arrangements were tested to get maximum performances and simplicity of the method. The performances of the method were studied in terms of chemical yields of uranium and thorium and removal of the potentially interfering elements. The established method was applied to samples from a chemical industry and sediments collected in a NORM-polluted scenario. The results obtained from our method allowed us to infer not only the extent, but also the sources of the contamination in the area. PMID:22230754

Mas, J L; Villa, M; Hurtado, S; García-Tenorio, R

2011-12-30

374

Treating urine by Spirulina platensis  

NASA Astrophysics Data System (ADS)

In this paper Spirulina platensis with relatively high nutrition was cultivated to treat human urine. Batch culture showed that the consumption of N in human urine could reach to 99%, and the consumption of P was more than 99.9%, and 1.05 g biomass was obtained by treating 12.5 ml synthetic human urine; continuous culture showed that S. platensis could consume N, Cl, K and S in human urine effectively, and the consumption could reach to 99.9%, 75.0%, 83.7% and 96.0%, respectively, and the consumption of P was over 99.9%, which is very important to increase the closure and safety of the bioregenerative life support system (BLSS).

Yang, Chenliang; Liu, Hong; Li, Ming; Yu, Chengying; Yu, Gurevich

375

Determination of manganese in blood and urine by flameless atomic absorption spectrophotometry.  

PubMed

A method for the determination of manganese in blood and urine is described. A chelate fo manganese with cupferron is extracted with methylisobutylketone and determined by flameless atomic absorption spectrophotometry. The method is directly applicable to urine but the determination of manganese in blood required a preliminary digestion step. With the use of internal standards, this technique allows the determination of manganese concentrations of the order of 1 mug/1 of urine or 1 mug/100 ml whole blood. PMID:1000867

Buchet, J P; Lauwerys, R; Roels, H; De Vos, C

1976-12-01

376

HIV1 DNA in fibroblast cultures infected with urine from HIVseropositive cytomegalovirus (CMV) excretors  

Microsoft Academic Search

Summary Interactions between HIV-1 and CMV may be important in the pathogenesis of AIDS. We have studied whether active CMV infection alters the cell tropism of HIV-1 in dually-infected individuals. Urines from HIV-seropositive individuals excreting CMV were compared to urines from CMV non-excretors. Sixty-six urines from HIV-seropositive individuals were tested. Infectious HIV-1 was not detected in any of the concentrated

M. Margalith; R. T. D'Aquila; D. J. Manion; N. Basgoz; L. J. Bechtel; B. R. Smith; J. C. Kaplan; M. S. Hirsch

1995-01-01

377

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

PubMed

One hundred fifty seven fifth-grade students (aged 10-12 years) from three elementary schools in three different towns in Taichung County, Taiwan were chosen as study subjects for the present arsenic and lead exposure study. The three towns--Longgang, Shalach, and Shuntain--are known to be highly, moderately, and lightly (control) polluted by As and Pb, respectively. Spot morning urine samples of students were collected and analyzed for arsenic and lead. The levels of As in the urine of Longgang schoolchildren showed the highest value among the three schools, while those of the control group (Shuntain) had the lowest values. In addition, the levels of Pb in the urine of the schoolchildren in Shuntain were significantly lower than those in Longgang and Shalach, while the levels of Pb in the urine of the schoolchildren in Longgang and Shalach showed no significant difference. Results of daily intake of metals from the different exposure pathways (i.e., ingestion from drinking water, household dust and food, and inhalation from airborne particles) showed that the Longgang area had the highest daily intake of As and Pb among the three areas, while the lowest daily intake of As and Pb occurred in the control area (Shuntain). A significant correlation between the doses of daily intake and urinary concentrations of As (p = 0.002) and Pb (p = 0.020) was observed. This correlation suggests that the increase of unit dose of the daily intake for As resulted in an increase of 0.953 microg g(-1) creatinine of As, whereas the increase of unit dose of the daily intake for Pb led to an increase of 0.053 microg g(-1) creatinine of Pb. These data indicate that the level of As in urine increased about 18 times higher than that of Pb for the same amount of increase in daily intake. PMID:18781537

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

378

Urine Menthol as a Biomarker of Mentholated Cigarette Smoking  

PubMed Central

Objectives Menthol cigarettes are smoked by 27% of U.S. smokers, and there are concerns that menthol might enhance toxicity of cigarette smoking by increasing systemic absorption of smoke toxins. We measured urine menthol concentrations in relation to biomarkers of exposure to nicotine and tobacco carcinogens. Methods Concentrations of menthol glucuronide (using a novel analytical method), nicotine plus metabolites (nicotine equivalents, NE), 4-(methylnitrosamino)-1-(3)pyridyl-1-butanol (NNAL) and polycyclic aromatic hydrocarbon (PAH) metabolites were measured in the urine of 60 menthol and 67 regular cigarette smokers. Results Urine menthol was measurable in 82% of menthol and 54% in regular cigarette smokers. Among menthol smokers urine menthol was highly correlated with NE, NNAL and PAHs. In a multiple regression model NE but not menthol was significantly associated with NNAL and PAHs. Conclusions Urine menthol concentration is a novel biomarker of exposure in menthol cigarette smokers, and is highly correlated with exposure to nicotine and carcinogens. Menthol is not independently associated with carcinogen exposure when nicotine intake is considered.

Benowitz, Neal L; Dains, Katherine M.; Dempsey, Delia; Havel, Christopher; Wilson, Margaret; Jacob, Peyton

2010-01-01

379

Tamm-Horsfall mucoproteins promote calcium oxalate crystal formation in urine: quantitative studies  

Microsoft Academic Search

The technique of rapid evaporation of whole urine to standard osmolality has been studied further and quantitative measurements made of the calcium oxalate crystals resulting, firstly by a microscope method and secondly by isotope method using 14C-oxalate. It is confirmed that ultrafiltration of urine prior to evaporation leads to a large reduction in calcium oxalate crystal formation and that this

G. A. Rose; S. Sulaiman

1982-01-01

380

Comparison of Trace Level Concentrations for Silver, Arsenic, Barium, Cadmium, and Lead in Drinking Waters Obtained by Inductively Coupled Plasma-Mass Spectrometry and Electrothermal-Vaporization Atomic Absorption Spectroscopy.  

National Technical Information Service (NTIS)

The authors compared the data obtained by inductively coupled plasma-mass spectrometry (ICP-MS) and electrothermal-vaporization atomic absorption spectroscopy (ETVAA), for concentration values of silver, arsenic, barium, cadmium, and lead in drinking wate...

R. Robinson M. Bell C. Burns D. Knab

1987-01-01

381

Amphetamine Positive Urine Toxicology Screen Secondary to Atomoxetine  

PubMed Central

The aim of this paper is to report the first case of atomoxetine leading to false-positive urine drug screen. An otherwise healthy 27-year-old female with a history of attention deficit hyperactivity disorder (ADHD) treated with atomoxetine had an acute onset tonic-clonic seizure. On arrival to the hospital, a urine toxicological drug screen with immunochemical cloned enzyme donor immunoassay (CEDIA) was performed. Results were positive for amphetamines; however, the presence of these substances could not be confirmed with urine gas chromatography-mass spectrometry (GC-MS). She denied any illicit drug use, herbal medications, or supplements, and her other prescription medications have not been previously known to cause a false-positive result for amphetamines. While stimulant treatments for ADHD could certainly result in a positive result on urine screen for amphetamines, there have been no reports of false-positive results for amphetamines secondary to patients using atomoxetine. We implicate atomoxetine, and/or its metabolites, as a compound or compounds which may interfere with urine drug immunoassays leading to false-positive results for amphetamines CEDIA assays.

Fenderson, Joshua L.; Stratton, Amy N.; Domingo, Jennifer S.; Matthews, Gerald O.; Tan, Christopher D.

2013-01-01

382

Metals in Urine and Peripheral Arterial Disease  

PubMed Central

Exposure to metals may promote atherosclerosis. Blood cadmium and lead were associated with peripheral arterial disease (PAD) in the 1999–2000 National Health and Nutrition Examination Survey (NHANES). In the present study we evaluated the association between urinary levels of cadmium, lead, barium, cobalt, cesium, molybdenum, antimony, thallium, and tungsten with PAD in a cross-sectional analysis of 790 participants ?40 years of age in NHANES 1999–2000. PAD was defined as a blood pressure ankle brachial index < 0.9 in at least one leg. Metals were measured in casual (spot) urine specimens by inductively coupled plasma–mass spectrometry. After multivariable adjustment, subjects with PAD had 36% higher levels of cadmium in urine and 49% higher levels of tungsten compared with noncases. The adjusted odds ratio for PAD comparing the 75th to the 25th percentile of the cadmium distribution was 3.05 [95% confidence interval (CI), 0.97 to 9.58]; that for tungsten was 2.25 (95% CI, 0.97 to 5.24). PAD risk increased sharply at low levels of antimony and remained elevated beyond 0.1 ?g/L. PAD was not associated with other metals. In conclusion, urinary cadmium, tungsten, and possibly antimony were associated with PAD in a representative sample of the U.S. population. For cadmium, these results strengthen previous findings using blood cadmium as a biomarker, and they support its role in atherosclerosis. For tungsten and antimony, these results need to be interpreted cautiously in the context of an exploratory analysis but deserve further study. Other metals in urine were not associated with PAD at the levels found in the general population.

2005-01-01

383

Lead control  

SciTech Connect

Lead has been known to affect children's brains for at least 80 years, but regulation has lagged far behind the science, primarily because of the unrelenting activity of the lead industry and its spokespersons. The result was that we did not pass a Lead Paint Poisoning Prevention Act in this country until 1971. Recoiling from a new spate of lawsuits the lead industry is once again attacking the data base that drew the federal government to certify that blood lead concentrations above 10 micrograms per deciliter ({mu}g/dl) are neurotoxic. The Public Health Service, having recognized that childhood lead poisoning is one of the most serious problems for the children in the US and that it is an eradicable disease, has drafted a Strategic Plan that, if implemented, will begin the process of breaking the exposure link by getting lead out of the environment before it finds its way into children's brains. It now appears that the White House has decided that increased federal participation will not take place. This would be a tragedy and cannot be allowed to happen without a complete discussion of the costs to our society.

Needleman, H.L. (Univ. of Pittsburgh, PA (United States))

1991-10-25

384

Ameliorative Effect of Vitamin C on Alterations in Thyroid Hormones Concentrations Induced by Subchronic Coadministration of Chlorpyrifos and Lead in Wistar Rats  

PubMed Central

The present study evaluated the ameliorative effect of vitamin C on alteration in thyroid hormones induced by low-dose subchronic coadministration of chlorpyrifos (CPF) and lead (Pb). Forty Wistar rats were divided into 4 groups of 10 animals each. Groups I and II were administered soya oil (2?mL/kg) and vitamin C (100?mg/kg), respectively. Group III was coadministered CPF (4.25?mg/kg ~1/20th LD50) and Pb (250?mg/kg ~1/20th LD50), respectively. Group IV was pretreated with vitamin C (100?mg/kg) and then coadministered with CPF (4.25?mg/kg) and Pb (250?mg/kg), 30?min later. The regimens were administered by gavage for a period of 9 weeks. The marginal decrease in serum triiodothyronine and thyroxine and the significant increase in the concentrations of thyroid stimulating hormone and malonaldehyde in the group coadministered with CPF and Pb were ameliorated by vitamin C partly due to its antioxidant properties.

Ambali, Suleiman F.; Orieji, Chinedu; Abubakar, Woziri O.; Shittu, Muftau; Kawu, Mohammed U.

2011-01-01

385

Blood lead, ethnic origin, and lead exposure  

Microsoft Academic Search

A survey of blood lead concentrations is reported in a group of 199 young Walsall children (3-6 years of age). The geometric mean blood lead concentration was 0.47 mumol\\/l (range 0.2-1.6 mumol\\/l). There were no significant differences in blood lead concentrations between groups of children with different ages, sex, ethnic origin, or environment.

G M Singal; A R Gatrad; P M Howse; K W Johnson; M Ganley; A Thomas; R A Braithwaite; S S Brown

1988-01-01

386

Higher urine desmosine levels are associated with mortality in patients with acute lung injury  

PubMed Central

Desmosine is a stable breakdown product of elastin that can be reliably measured in urine samples. We tested the hypothesis that higher baseline urine desmosine would be associated with higher mortality in 579 of 861 patients included in the recent Acute Respiratory Distress Syndrome Network trial of lower tidal volume ventilation (1). We also correlated urine desmosine levels with indexes of disease severity. Finally, we assessed whether urine desmosine was lower in patients who received lower tidal volumes. Desmosine was measured by radioimmunoassay in urine samples from days 0, 1, and 3 of the study. The data were expressed as a ratio of urine desmosine to urine creatinine to control for renal dilution. The results show that higher baseline (day 0) urine desmosine-to-creatinine concentration was associated with a higher risk of death on adjusted analysis (odds ratio 1.36, 95% confidence interval 1.02-1.82, P = 0.03). Urine desmosine increased in both ventilator groups from day 0 to day 3, but the average rise was higher in the 12-ml/kg predicted body weight group compared with the 6-ml/kg predicted body weight group (P = 0.053, repeated-measures model). In conclusion, patients with acute lung injury ventilated with lower tidal volumes have lower urine desmosine levels, a finding that may reflect reduced extracellular matrix breakdown. These results illustrate the value of evaluating urinary biological markers that may have prognostic and pathogenetic significance in acute lung injury.

McClintock, Dana E.; Starcher, Barry; Eisner, Mark D.; Thompson, B. Taylor; Hayden, Doug L.; Church, Gwynne D.; Matthay, Michael A.

2009-01-01

387

Phosphate recovery using hybrid anion exchange: Applications to source-separated urine and combined wastewater streams.  

PubMed

There is increasing interest in recovering phosphorus (P) from various wastewater streams for beneficial use as fertilizer and to minimize environmental impacts of excess P on receiving waters. One such example is P recovery from human urine, which has a high concentration of phosphate (200-800 mg P/L) and accounts for a small volume (?1%) of total wastewater flow. Accordingly, the goal of this study was to evaluate the potential to recover P from source-separated and combined wastewater streams that included undiluted human urine, urine diluted with tap water, greywater, mixture of urine and greywater, anaerobic digester supernatant, and secondary wastewater effluent. A hybrid anion exchange (HAIX) resin containing hydrous ferric oxide was used to recover P because of its selectivity for phosphate and the option to precipitate P minerals in the waste regeneration solution. The P recovery potential was fresh urine > hydrolyzed urine > greywater > biological wastewater effluent > anaerobic digester supernatant. The maximum loading of P on HAIX resin was fresh urine > hydrolyzed urine > anaerobic digester supernatant ? greywater > biological wastewater effluent. Results indicated that the sorption capacity of HAIX resin for phosphate and the total P recovery potential were greater for source-separated urine than the combined wastewater streams of secondary wastewater effluent and anaerobic digester supernatant. Dilution of urine with tap water decreased the phosphate loading on HAIX resin. The results of this work advance the current understanding of nutrient recovery from complex wastewater streams by sorption processes. PMID:23866131

O'Neal, Jeremy A; Boyer, Treavor H

2013-05-31

388

High-resolution determination of {sup 147}Pm in urine using dynamic ion-exchange chromatography  

SciTech Connect

Ion exchange preconcentration followed by HPLC purification prior to scintillation counting was used to measure the concentration of {sup 147}Pm in urine. the detection limit for this method was found to be 0.1 Bq (3 fg) of {sup 147}Pm in 500 ml of urine.

Elchuk, S.; Lucy, C.A.; Burns, K.I. [Chalk River Labs., Ontario (Canada)

1992-10-15

389

Relationship Between ?-Hydroxybutyrate and Acetoacetate Plus Acetone Contents of Blood and Urine of the Ruminant  

Microsoft Academic Search

Separation of the blood plasma, whole blood, and urine ketones was made under normal conditions and in various states of hyperketonemia and ketonuria. The rela- tionship of blood level of a given ketone fraction to urine concentration and total excretion of that ketone fraction was best expressed as a log-log equation for both the acetoacetie acid plus acetone fraction and

L. A. Menahan; W. B. Holtmann; L. H. Schultz; W. G. Hoekstra

1967-01-01

390

The in£uence of synthetic sheep urine on ammonia oxidizing bacterial communities in grassland soil  

Microsoft Academic Search

In grazed, grassland soils, sheep urine generates heterogeneity in ammonia concentrations, with potential impact on ammonia oxidizer community structure and soil N cycling. The influence of different levels of synthetic sheep urine on ammonia oxidizers was studied in grassland soil microcosms. 'Total' and active ammonia oxidizers were distinguished by comparing denaturing gradient gel electrophoresis (DGGE) profiles following PCR and RT-PCR

Shahid Mahmood; James I. Prosser

391

A Simple Method for the Quantitative Determination of N-Acetyl-p-Aminophenol (APAP) in Urine  

Microsoft Academic Search

A simple method is describedfor the rapid quantitative analysisof N-acetyl-p-amino- phenol (APAP) in urine. APAP and its conjugates present in the urine following the ingestion of acetophenetidin, APAP or acetanilid, are hydrolyzed with acid to p. aminophenol. This compoundis coupledwith phenolin the presenceof hypobromiteto form an indophenol dye whose concentration is determined spectrophotometrically. Application of this method to a study

Richard M. Welch; A. H. Conney

392

Soil pH and nitrogen changes following cattle and sheep urine deposition  

Microsoft Academic Search

The relationship between animal urine deposition and variability in soil chemical composition and crop growth is not well established in the semi?arid region of West Africa. This study was conducted to examine the changes over time in soil pH and mineral nitrogen (N) concentrations at the micro sites of cattle and sheep urine patches in comparison to those occurring in

Zana C. Somda; J. Mark Powell; André Bationo

1997-01-01

393

An Antiserum for the Specific Detection of HCG in Human Urine.  

National Technical Information Service (NTIS)

The invention relates generally to a method for in vitro determination of human chorionic gonadotropin (hCG) concentration in urine wherein the determination from urine is specific for hCG and excludes human luteinizing hormone (hLH). More particularly th...

G. D. Hodgen H. C. Chen S. Matsuura

1977-01-01

394

Applicability of two mobile analysers for mercury in urine in small-scale gold mining areas  

Microsoft Academic Search

Mercury is still used in developing countries to extract gold from the ore in small-scale gold mining areas. This is a major health hazard for people living in mining areas. The concentration of mercury in urine was analysed in different mining areas in Zimbabwe, Indonesia and Tanzania. First the urine samples were analysed by CV-AAS (cold vapour atomic absorption spectrometry)

Jennifer Baeuml; Stephan Bose-O’Reilly; Beate Lettmeier; Alexandra Maydl; Katalin Messerer; Gabriele Roider; Gustav Drasch; Uwe Siebert

395

Absorbing and diffusive properties of blood plasma and urine proteins  

NASA Astrophysics Data System (ADS)

An analysis of absorbing and scattering properties of blood and urine plasma proteins is presented. Assessment methods of their spectroscopic parameters, such as extinction, absorption and scattering coefficients, are described. Possibilities for a separate assessment of the albumin and globulin concentrations in biological media are considered.

Guminetsky, S. G.; Pishak, Olga V.; Pishak, V. P.; Grigorishin, P. M.

1997-12-01

396

Enzyme immunoassay validation for the detection of buprenorphine in urine.  

PubMed

A solid-phase enzyme immunoassay involving microtiter plates was proposed by Microgenics to screen buprenorphine in urine. The intra-assay precision at 10 ng/mL was 7.7% (coefficient of variation). The immunoassay was determined to have no cross-reactivity with codeine, dihydrocodeine, morphine, ethylmorphine, 6-monoacetylmorphine, methadone, pholcodine, propoxyphene, dextromoramide, and dextromethorphan at 1 and 10 mg/L. A low cross-reactivity (3% at 1 ng/mL) was observed at low concentrations of norbuprenorphine. After comparing this new immunological test (Singlestep ELISA) for 76 urine specimens with our validated high-performance liquid chromatography-electrospray mass spectrometry (HPLC-ES-MS) procedure, an optimum cutoff concentration of 2 ng/mL was determined for the kit. At this cutoff, the screening assay was able to determine more than 90% of true results with 43.4% true positives and 48.7% true negatives. Four positive urines (5.3%) were not confirmed by HPLC-ES-MS. In only one case, the negative urine test was confirmed as positive by HPLC-ES-MS (buprenorphine: 62.5 ng/mL). Buprenorphine concentrations determined by HPLC-ES-MS ranged from 1.2 to 1052 ng/mL. Of the four potential adulterants (hypochloride 50 mL/L, sodium nitrite 50 g/L, liquid soap 50 mL/L, and sodium chloride 50 g/L) that might be added to a positive urine specimen, none were able to cause a false-negative response by the immunoassay. The results of this study support the concept that the Singlestep ELISA for buprenorphine determination in urine should be considered as a new, valided screening procedure. PMID:12670004

Cirimele, V; Kintz, P; Lohner, S; Ludes, B

2003-03-01

397

Luminol Chemiluminescence in Urine Analysis  

Microsoft Academic Search

The purpose of the present review is to sketch out the scope of luminol chemiluminescence in human urine analysis. Practical considerations and experimental requirements are indicated. The literature revised covers the papers of analytical interest that have appeared in approximately the last six years.

Ana María Jiménez Moreno; María José Navas Sánchez

2006-01-01

398

Urine specimen detection of concurrent nonprescribed medicinal and illicit drug use in patients prescribed buprenorphine.  

PubMed

Patients being treated with buprenorphine usually have a history of opioid dependence and may be predisposed to misuse of drugs. Concurrent drug misuse increases the risk of life-threatening drug interactions. This retrospective data analysis observed which nonprescribed and illicit drugs were most commonly detected in the urine of patients from pain management clinics taking buprenorphine with or without a prescription. GC, LC/MS and LC-MS-MS were used to quantify 20,929 urine specimens. The most prevalent illicit drug used in both the groups (prescribed and nonprescribed buprenorphine) was marijuana, followed by cocaine. The most prevalent nonprescribed medications abused by both the groups were benzodiazepines, followed by oxycodone and hydrocodone. The overall prevalence of illicit and nonprescribed drug use was significantly higher in subjects who used buprenorphine without a prescription versus prescribed use. Of the concurrent use of marijuana and cocaine with buprenorphine, cocaine is most concerning since it decreases exposure to buprenorphine (lower area under the concentration-time curve and maximum concentration). The concurrent use of nonprescribed benzodiazepines with buprenorphine can cause excess sedation leading to respiratory depression and even death. These findings highlight the importance of educating patients about these potential toxicities. Furthermore, pain providers should consider expanding the spectrum of drugs that they monitor in patients under treatment. PMID:24080973

Guo, Alexander Y; Ma, Joseph D; Best, Brookie M; Atayee, Rabia S

2013-09-29

399

Organophosphorous pesticide breakdown products in house dust and children's urine.  

PubMed

Human exposure to preformed dialkylphosphates (DAPs) in food or the environment may affect the reliability of DAP urinary metabolites as biomarkers of organophosphate (OP) pesticide exposure. We conducted a study to investigate the presence of DAPs in indoor residential environments and their association with children's urinary DAP levels. We collected dust samples from homes in farmworker and urban communities (40 homes total, n=79 samples) and up to two urine samples from resident children ages 3-6 years. We measured six DAPs in all samples and eight DAP-devolving OP pesticides in a subset of dust samples (n=54). DAPs were detected in dust with diethylphosphate (DEP) being the most frequently detected (?60%); detection frequencies for other DAPs were ?50%. DEP dust concentrations did not significantly differ between communities, nor were concentrations significantly correlated with concentrations of chlorpyrifos and diazinon, the most frequently detected diethyl-OP pesticides (Spearman ?=-0.41 to 0.38, P>0.05). Detection of DEP, chlorpyrifos, or diazinon, was not associated with DEP and/or DEP+diethylthiophosphate detection in urine (Kappa coefficients=-0.33 to 0.16). Finally, estimated non-dietary ingestion intake from DEP in dust was found to be ?5% of the dose calculated from DEP levels in urine, suggesting that ingestion of dust is not a significant source of DAPs in urine if they are excreted unchanged. PMID:22781438

Quirós-Alcalá, Lesliam; Bradman, Asa; Smith, Kimberly; Weerasekera, Gayanga; Odetokun, Martins; Barr, Dana Boyd; Nishioka, Marcia; Castorina, Rosemary; Hubbard, Alan E; Nicas, Mark; Hammond, S Katharine; McKone, Thomas E; Eskenazi, Brenda

2012-07-11

400

Biological monitoring of cadmium exposure: reliability of spot urine samples.  

PubMed

Concentration-dilution of spot urine samples is a shortcoming of the biological monitoring of industrial xenobiotics. To ascertain whether the adjustment of urinary cadmium measured in spot samples is appropriate, urine samples were taken three times, once a week for 3 successive weeks, from 25 welders employed in the manufacture of jewelry (total 75 samples). Cadmium, creatinine, specific gravity, total urinary solutes, urinary volume and urinary flow rate were measured in 12-h collections and in spot samples taken immediately afterwards. Creatinine and total urinary solutes showed high inverse correlation with urinary flow rate (r = -0.858 and r = -0.768 respectively). Urinary cadmium displayed a similar trend but the correlation was not significant (r = -0.145). Creatinine adjustment of urinary cadmium values in spot samples increased the correlation with the same index in timed samples adjusted for urinary volume (r = -0.808) or urinary flow rate (r = 0.821) compared with non-adjustment (r = 0.732 and r = 0.738, respectively). Creatinine adjustment of spot sample values is also suitable for a wide range of urinary concentrations; discarding excessively diluted or concentrated urines, correlation of urine samples improved for non-adjusted or specific gravity-adjusted values, whereas no changes were observed for creatinine-adjusted values. PMID:8034361

Trevisan, A; Nicoletto, G; Maso, S; Grandesso, G; Odynets, A; Secondin, L

1994-01-01