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1

Concentrations and chemical species of arsenic in human urine and hair  

SciTech Connect

Because marine products are rich in arsenic, the concentration of arsenic in the human urine varies greatly with the state of ingestion of marine products. It has been revealed that inorganic arsenic is methylated in the human body to form MAA (methylarsonic acid) and DMAA (dimethylarsinic acid). It appears therefore that the arsenic present in the human urine is a mixture of the arsenic originating from marine products and the arsenic metabolized in vivo. Recent studies have shown that inorganic arsenic and methylarsenic compounds are quite different in toxicity and effect on the living body due to their difference in chemical species. Finding the chemical species of arsenic in the urine and hair of normal subjects will therefore provide valuable basal data for the biological monitoring of arsenic exposure and for toxicological studies of arsenic.

Yamato, Naohisa (St. Marianna Univ. School of Medicine, Kawasaki (Japan))

1988-05-01

2

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

3

Urine arsenic concentration and obstructive pulmonary disease in the U.S. population.  

PubMed

Arsenic (As) is a known carcinogen commonly found in drinking water. An emerging body of evidence suggests that exposure to inorganic As may be associated with nonmalignant respiratory disease. The aim of this study was to determine whether there is an association between As exposure at levels seen in the United States and prevalence of asthma, emphysema, chronic bronchitis, and respiratory symptoms.Urinary As was collected from 5365 participants from the combined 2003-2006 National Health and Nutrition Examination Survey (NHANES) cohorts. Two methods to adjust for organic As component were incorporated into the statistical model. Linear and logistic regression models compared urinary As adjusted for organic As with diagnoses of obstructive pulmonary disease and respiratory symptoms.Geometric mean concentration of urinary As were not significantly different between participants with and those without asthma, chronic bronchitis,and emphysema. Odds of having asthma was 0.71 for participants with the highest quintile of urinary As (? 17.23 ?g/dl) when compared to the lowest quintile (? 3.52 ?g/dl). A significant association was found between increasing urinary As concentration and decreasing age, male gender, and non-"white" race.A significant association between urinary As and obstructive pulmonary disease and symptoms was not demonstrated in the U.S. population. PMID:21480046

Amster, Eric D; Cho, Jang Ik; Christiani, David

2011-01-01

4

URINE ARSENIC CONCENTRATION AND OBSTRUCTIVE PULMONARY DISEASE IN THE U.S. POPULATION  

PubMed Central

Arsenic (As) is a known carcinogen commonly found in drinking water. An emerging body of evidence suggests that exposure to inorganic As may be associated with nonmalignant respiratory disease. The aim of this study was to determine whether there is an association between As exposure at levels seen in the United States and prevalence of asthma, emphysema, chronic bronchitis, and respiratory symptoms.Urinary As was collected from 5365 participants from the combined 2003–2006 National Health and Nutrition Examination Survey (NHANES) cohorts. Two methods to adjust for organic As component were incorporated into the statistical model. Linear and logistic regression models compared urinary As adjusted for organic As with diagnoses of obstructive pulmonary disease and respiratory symptoms. Geometric mean concentration of urinary As were not significantly different between participants with and those without asthma, chronic bronchitis, and emphysema. Odds of having asthma was 0.71 for participants with the highest quintile of urinary As (?17.23 ?g/dl) when compared to the lowest quintile (?3.52 ?g/dl). A significant association was found between increasing urinary As concentration and decreasing age, male gender, and non-“white” race. A significant association between urinary As and obstructive pulmonary disease and symptoms was not demonstrated in the U.S. population.

Amster, Eric D.; Cho, Jang Ik; Christiani, David

2013-01-01

5

Extremely high urine arsenic level after remote seafood ingestion.  

PubMed

Urine testing for heavy metal concentrations is increasingly performed in the outpatient setting as a part of laboratory evaluation for neuropathy. Abnormal urine arsenic levels due to dietary intake of organic arsenic can lead to unnecessary chelation therapy. A 54-year-old man underwent a 24-hour urine collection for heavy metal concentrations in evaluation of paresthesia of the right foot. The total arsenic level was 8880 ?g/d with concentrations of 4749 ?g/L and 3769 ?g/g creatinine. He was urgently referred to the toxicology clinic for consideration of chelation therapy. History revealed consumption of 2 lobster tails 5 days before the testing. Speciation was then performed on the original urine specimen and revealed an organic arsenic concentration of 4332 ?g/L. No inorganic or methylated arsenic was detected. Repeat testing after abstaining from seafood demonstrated a total arsenic level of 50 ?g/d with concentrations of 30 ?g/L and 21 ?g/g creatinine. Our patient demonstrates the highest level of arsenobetaine reported in the literature, and this level is higher than expected for a person who had not consumed seafood for 5 days before testing. The high levels may be due to consumption of food that he did not recognize as containing arsenobetaine or that his clearance of arsenobetaine from the ingested lobster is slower than published ranges. This case demonstrates the importance of speciation when measuring urine arsenic levels to avoid unnecessary chelation therapy. PMID:22407195

Nańagas, Kristine A; Tormoehlen, Laura M

2014-01-01

6

Binational Arsenic Exposure Survey: Methodology and Estimated Arsenic Intake from Drinking Water and Urinary Arsenic Concentrations  

PubMed Central

The Binational Arsenic Exposure Survey (BAsES) was designed to evaluate probable arsenic exposures in selected areas of southern Arizona and northern Mexico, two regions with known elevated levels of arsenic in groundwater reserves. This paper describes the methodology of BAsES and the relationship between estimated arsenic intake from beverages and arsenic output in urine. Households from eight communities were selected for their varying groundwater arsenic concentrations in Arizona, USA and Sonora, Mexico. Adults responded to questionnaires and provided dietary information. A first morning urine void and water from all household drinking sources were collected. Associations between urinary arsenic concentration (total, organic, inorganic) and estimated level of arsenic consumed from water and other beverages were evaluated through crude associations and by random effects models. Median estimated total arsenic intake from beverages among participants from Arizona communities ranged from 1.7 to 14.1 µg/day compared to 0.6 to 3.4 µg/day among those from Mexico communities. In contrast, median urinary inorganic arsenic concentrations were greatest among participants from Hermosillo, Mexico (6.2 µg/L) whereas a high of 2.0 µg/L was found among participants from Ajo, Arizona. Estimated arsenic intake from drinking water was associated with urinary total arsenic concentration (p < 0.001), urinary inorganic arsenic concentration (p < 0.001), and urinary sum of species (p < 0.001). Urinary arsenic concentrations increased between 7% and 12% for each one percent increase in arsenic consumed from drinking water. Variability in arsenic intake from beverages and urinary arsenic output yielded counter intuitive results. Estimated intake of arsenic from all beverages was greatest among Arizonans yet participants in Mexico had higher urinary total and inorganic arsenic concentrations. Other contributors to urinary arsenic concentrations should be evaluated.

Roberge, Jason; O'Rourke, Mary Kay; Meza-Montenegro, Maria Mercedes; Gutierrez-Millan, Luis Enrique; Burgess, Jefferey L.; Harris, Robin B.

2012-01-01

7

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

8

Assessment of occupational exposure to inorganic arsenic based on urinary concentrations and speciation of arsenic  

Microsoft Academic Search

An analytical speciation method, capable of separating inorganic arsenic (As (V), As (III] and its methylated metabolites (MMAA, DMAA) from common, inert, dietary organoarsenicals, was applied to the determination of arsenic in urine from a variety of workers occupationally exposed to inorganic arsenic compounds. Mean urinary arsenic (As (V) + As (III) + MMAA + DMAA) concentrations ranged from 4.4

J G Farmer; L R Johnson

1990-01-01

9

Pattern of Excretion of Arsenic Compounds [Arsenite, Arsenate, MMA(V), DMA(V)] in Urine of Children Compared to Adults from an Arsenic Exposed Area in Bangladesh  

Microsoft Academic Search

Urinary arsenic is generally considered as the most reliable indicator of recent exposure to inorganic arsenic and is used as the main bio-marker of exposure. However, due to the different toxicity of arsenic compounds, speciation of arsenic in urine is generally considered to be more convenient for health risk assessment than measuring total arsenic concentration. Additionally, it can give valuable

Uttam Kumar Chowdhury; Mohammad Mahmudur Rahman; Mrinal Kumar Sengupta; Dilip Lodh; Chitta Ranjan Chanda; Shibtosh Roy; Quazi Quamruzzaman; Hiroshi Tokunaga; Masanori Ando; Dipankar Chakraborti

2003-01-01

10

Stability of arsenic species and insoluble arsenic in human urine.  

PubMed

Urinary arsenic species are important short-term biomarkers that have been used in epidemiological studies. However, the stability of soluble arsenic species and the amount of arsenic lost during sample pretreatment remain unclear. The objective of this study is to evaluate the stability of soluble arsenic species in urine and aqueous standards, as well as to assess the amount of insoluble and soluble arsenic lost during pretreatment (centrifugation and filtration, respectively). High-performance liquid chromatogram inductively coupled plasma mass spectrometry was used to speciate arsenic species [Arsenite [As(III)], arsenate [As(V)], monomethylarsonic acid [MMA(V)], monomethylarsonous acid [MMA(III)], dimethylarsinic acid [DMA(V)], and arsenobetaine [AsB

Chen, Yen-Ching; Amarasiriwardena, Chitra J; Hsueh, Yu-Mei; Christiani, David C

2002-11-01

11

Biological monitoring of arsenic exposure of gallium arsenide- and inorganic arsenic-exposed workers by determination of inorganic arsenic and its metabolites in urine and hair  

SciTech Connect

In an attempt to establish a method for biological monitoring of inorganic arsenic exposure, the chemical species of arsenic were measured in the urine and hair of gallium arsenide (GaAs) plant and copper smelter workers. Determination of urinary inorganic arsenic concentration proved sensitive enough to monitor the low-level inorganic arsenic exposure of the GaAs plant workers. The urinary inorganic arsenic concentration in the copper smelter workers was far higher than that of a control group and was associated with high urinary concentrations of the inorganic arsenic metabolites, methylarsonic acid (MAA) and dimethylarsinic acid (DMAA). The results established a method for exposure level-dependent biological monitoring of inorganic arsenic exposure. Low-level exposures could be monitored only by determining urinary inorganic arsenic concentration. High-level exposures clearly produced an increased urinary inorganic arsenic concentration, with an increased sum of urinary concentrations of inorganic arsenic and its metabolites (inorganic arsenic + MAA + DMAA). The determination of urinary arsenobetaine proved to determine specifically the seafood-derived arsenic, allowing this arsenic to be distinguished clearly from the arsenic from occupational exposure. Monitoring arsenic exposure by determining the arsenic in the hair appeared to be of value only when used for environmental monitoring of arsenic contamination rather than for biological monitoring.

Yamauchi, H.; Takahashi, K.; Mashiko, M.; Yamamura, Y. (St. Marianna Univ. School of Medicine, Kawasaki (Japan))

1989-11-01

12

Excretion of arsenic in urine as a function of exposure to arsenic in drinking water.  

PubMed Central

Urinary arsenic (As) concentrations were evaluated as a biomarker of exposure in a U.S. population chronically exposed to inorganic As (InAs) in their drinking water. Ninety-six individuals who consumed drinking water with As concentrations of 8-620 microg/L provided first morning urine voids for up to 5 consecutive days. The study population was 56% male, and 44% was younger than 18 years of age. On one day of the study period, all voided urines were collected over a 24-hr period. Arsenic intake from drinking water was estimated from daily food diaries. Comparison between the concentration of As in individual urine voids with that in the 24-hr urine collection indicated that the concentration of As in urine was stable throughout the day. Comparison of the concentration of As in each first morning urine void over the 5-day study period indicated that there was little day-to-day variation in the concentration of As in urine. The concentration of As in drinking water was a better predictor of the concentration of As in urine than was the estimated intake of As from drinking water. The concentration of As in urine did not vary by gender. An age-dependent difference in the concentration of As in urine may be attributed to the higher As dosage rate per unit body weight in children than in adults. These findings suggest that the analysis of a small number of urine samples may be adequate to estimate an individual's exposure to InAs from drinking water and that the determination of the concentration of InAs in a drinking water supply may be a useful surrogate for estimating exposure to this metalloid. Images Figure 1 Figure 2 Figure 3 Figure 4

Calderon, R L; Hudgens, E; Le, X C; Schreinemachers, D; Thomas, D J

1999-01-01

13

Seasonal perspective of dietary arsenic consumption and urine arsenic in an endemic population.  

PubMed

Exposure to arsenic in arsenic endemic areas is most remarkable environmental health challenges. Although effects of arsenic contamination are well established, reports are unavailable on probable seasonal variation due to changes of food habit depending on winter and summer seasons, especially for endemic regions of Nadia district, West Bengal. Complete 24-h diets, drinking-cooking water, first morning voided urine samples, and diet history were analyzed on 25 volunteers in arsenic endemic Chakdah block of Nadia district, once in summer followed by once in winter from the same participants. Results depicted no seasonal variation of body weight and body mass index. Arsenic concentration of source drinking and cooking water decreased (p?=?0.04) from 26 ?g L(-1) in summer to 6 ?g L(-1) in winter season. We recorded a seasonal decrease of water intake in male (3.8 and 2.5 L day (-1)) and female (2.6 and 1.2 L day(-1)) participants from summer to winter. Arsenic intake through drinking water decreased (p?=?0.04) in winter (29 ?g day(-1)) than in summer (100 ?g day(-1)), and urinary arsenic concentration decreased (p?=?0.018) in winter (41 ?g L(-1)) than in summer (69 ?g L(-1)). Dietary arsenic intake remained unchanged (p?=?0.24) over the seasons. Hence, we can infer that human health risk assessment from arsenic needs an insight over temporal scale. PMID:24676993

Biswas, Anirban; Deb, Debasree; Ghose, Aloke; Santra, Subhas Chandra; Guha Mazumder, Debendra Nath

2014-07-01

14

Urine Arsenic and Prevalent Albuminuria: Evidence From a Population-Based Study  

PubMed Central

Background Chronic arsenic exposure is a major global health problem. Few epidemiologic studies, however, have evaluated the association of arsenic with kidney measures. Our objective was to evaluate the cross-sectional association between inorganic arsenic exposure and albuminuria in American Indian adults from rural areas of Arizona, Oklahoma and North and South Dakota. Study Design Cross-sectional. Setting & Partipants Strong Heart Study locations in Arizona, Oklahoma, and North and South Dakota. 3,821 American Indian men and women 45 to 74 years of age with urine arsenic and albumin measures. Predictor Urine arsenic. Outcomes Urine albumin/creatinine ratio and albuminuria status. Measurements Arsenic exposure was estimated by measuring total urine arsenic and urine arsenic species using inductively coupled plasma-mass spectrometry (ICPMS) and high performance liquid chromatography-ICPMS, respectively. Urine albumin was measured by automated nephelometric immunochemistry. Results The prevalence of albuminuria (albumin-creatinine ratio, ?30 mg/g) was 30%. The median value for the sum of inorganic and methylated arsenic species was 9.7 (IQR, 5.8-15.6) ?g/g creatinine. The multivariable-adjusted prevalence ratios of albuminuria (albumin-creatinine ratio. ?30 mg/g) comparing the three highest to lowest quartiles of the sum of inorganic and methylated arsenic species were 1.16 (95% CI, 1.00-1.34), 1.24 (95% CI, 1.07-1.43), and 1.55 (95% CI, 1.35-1.78), respectively (P for trend <0.001). The association between urine arsenic and albuminuria was observed across all participant subgroups evaluated and was evident for both micro and macroalbuminuria. Limitations The cross-sectional design cannot rule out reverse causation. Conclusions Increasing urine arsenic concentrations were cross-sectionally associated with increased albuminuria in a rural US population with a high burden of diabetes and obesity. Prospective epidemiologic and mechanistic evidence is needed to understand the role of arsenic as a kidney disease risk factor.

Zheng, Laura Y.; Umans, Jason G.; Tellez-Plaza, Maria; Yeh, Fawn; Francesconi, Kevin A.; Goessler, Walter; Silbergeld, Ellen K.; Guallar, Eliseo; Howard, Barbara V.; Weaver, Virginia M.; Navas-Acien, Ana

2012-01-01

15

ARSENIC LEVELS IN HUMAN BLOOD, URINE, AND HAIR IN RESPONSE TO EXPOSURE VIA DRINKING WATER  

EPA Science Inventory

Five communities with water supplies having arsenic concentrations of 6, 51, 98, 123 and 393 micrograms/liter were selected for study. Samples of blood, hair, urine and tap water were obtained from participants in each community and analyzed for arsenic content. Results showed an...

16

Heritability and Preliminary Genome-Wide Linkage Analysis of Arsenic Metabolites in Urine  

PubMed Central

Background: Arsenic (III) methyltransferase (AS3MT) has been related to urine arsenic metabolites in association studies. Other genes might also play roles in arsenic metabolism and excretion. Objective: We evaluated genetic determinants of urine arsenic metabolites in American Indian adults from the Strong Heart Study (SHS). Methods: We evaluated heritability of urine arsenic metabolites [percent inorganic arsenic (%iAs), percent monomethylarsonate (%MMA), and percent dimethylarsinate (%DMA)] in 2,907 SHS participants with urine arsenic measurements and at least one relative within the cohort. We conducted a preliminary linkage analysis in a subset of 487 participants with available genotypes on approximately 400 short tandem repeat markers using a general pedigree variance component approach for localizing quantitative trait loci (QTL). Results: The medians (interquartile ranges) for %iAs, %MMA, and %DMA were 7.7% (5.4–10.7%), 13.6% (10.5–17.1%), and 78.4% (72.5–83.1%), respectively. The estimated heritability was 53% for %iAs, 50% for %MMA, and 59% for %DMA. After adjustment for sex, age, smoking, body mass index, alcohol consumption, region, and total urine arsenic concentrations, LOD [logarithm (to the base of 10) of the odds] scores indicated suggestive evidence for genetic linkage with QTLs influencing urine arsenic metabolites on chromosomes 5 (LOD = 2.03 for %iAs), 9 (LOD = 2.05 for %iAs and 2.10 for %MMA), and 11 (LOD = 1.94 for %iAs). A peak for %DMA on chromosome 10 within 2 Mb of AS3MT had an LOD of 1.80. Conclusions: This population-based family study in American Indian communities supports a genetic contribution to variation in the distribution of arsenic metabolites in urine and, potentially, the involvement of genes other than AS3MT.

Tellez-Plaza, Maria; Gribble, Matthew O.; Voruganti, V. Saroja; Francesconi, Kevin A.; Goessler, Walter; Umans, Jason G.; Silbergeld, Ellen K.; Guallar, Eliseo; Franceschini, Nora; Kao, Wen H.; MacCluer, Jean W.; Cole, Shelley A.

2013-01-01

17

Determination of monomethylarsonous acid, a key arsenic methylation intermediate, in human urine.  

PubMed Central

In this study we report on the finding of monomethylarsonous acid [MMA(III)] in human urine. This newly identified arsenic species is a key intermediate in the metabolic pathway of arsenic biomethylation, which involves stepwise reduction of pentavalent to trivalent arsenic species followed by oxidative addition of a methyl group. Arsenic speciation was carried out using ion-pair chromatographic separation of arsenic compounds with hydride generation atomic fluorescence spectrometry detection. Speciation of the inorganic arsenite [As(III)], inorganic arsenate [As(V)], monomethylarsonic acid [MMA(V)], dimethylarsinic acid [DMA(V)], and MMA(III) in a urine sample was complete in 5 min. Urine samples collected from humans before and after a single oral administration of 300 mg sodium 2,3-dimercapto-1-propane sulfonate (DMPS) were analyzed for arsenic species. MMA(III) was found in 51 out of 123 urine samples collected from 41 people in inner Mongolia 0-6 hr after the administration of DMPS. MMA(III )in urine samples did not arise from the reduction of MMA(V) by DMPS. DMPS probably assisted the release of MMA(III) that was formed in the body. Along with the presence of MMA(III), there was an increase in the relative concentration of MMA(V) and a decrease in DMA(V) in the urine samples collected after the DMPS ingestion.

Le, X C; Ma, M; Cullen, W R; Aposhian, H V; Lu, X; Zheng, B

2000-01-01

18

Assessment of occupational exposure to inorganic arsenic based on urinary concentrations and speciation of arsenic.  

PubMed Central

An analytical speciation method, capable of separating inorganic arsenic (As (V), As (III] and its methylated metabolites (MMAA, DMAA) from common, inert, dietary organoarsenicals, was applied to the determination of arsenic in urine from a variety of workers occupationally exposed to inorganic arsenic compounds. Mean urinary arsenic (As (V) + As (III) + MMAA + DMAA) concentrations ranged from 4.4 micrograms/g creatinine for controls to less than 10 micrograms/g for those in the electronics industry, 47.9 micrograms/g for timber treatment workers applying arsenical wood preservatives, 79.4 micrograms/g for a group of glassworkers using arsenic trioxide, and 245 micrograms/g for chemical workers engaged in manufacturing and handling inorganic arsenicals. The maximum recorded concentration was 956 micrograms/g. For the most exposed groups, the ranges in the average urinary arsenic speciation pattern were 1-6% As (V), 11-14% As (III), 14-18% MMAA, and 63-70% DMAA. The highly raised urinary arsenic concentrations for the chemical workers, in particular, and some glassworkers are shown to correspond to possible atmospheric concentrations in the workplace and intakes in excess of, or close to, recommended and statutory limits and those associated with inorganic arsenic related diseases.

Farmer, J G; Johnson, L R

1990-01-01

19

Understanding arsenic metabolism through a comparative study of arsenic levels in the urine, hair and fingernails of healthy volunteers from three unexposed ethnic groups in the United Kingdom  

Microsoft Academic Search

Very little is known about arsenic (As) metabolism in healthy populations that are not exposed to high concentrations of As in their food or water. Here we present a study with healthy volunteers from three different ethnic groups, residing in Leicester, UK, which reveals statistically significant differences in the levels of total As in urine and fingernail samples. Urine (n = 63),

Eid I. Brima; Parvez I.. Haris; Richard O. Jenkins; Dave A. Polya; Andrew G. Gault; Chris F. Harrington

2006-01-01

20

The influence of chemical form and concentration of arsenic on rice growth and tissue arsenic concentration  

Microsoft Academic Search

Arsenic absorption by rice (Oryza sativa, L.) in relation to the chemical form and concentration of arsenic added in nutrient solution was examined. A 4 × 3 × 2 factorial experiment was conducted with treatments consisting of four arsenic chemical forms [arsenite, As(III); arsenate, As(V); monomethyl arsenic acid, MMAA; and dimethyl arsenic acid, DMAA], three arsenic concentrations [0.05, 0.2, and

A. R. Marin; P. H. Masscheleyn; W. H. Patrick

1992-01-01

21

Recovery of Arsenic from Ores and Concentrates.  

National Technical Information Service (NTIS)

This invention relates to recovery of arsenic, in the form of As2O3, from arsenical ores and concentrates. Typical of such ores are arseno-pyrite, cobaltite, niccolite, enargite, and speiss. Concentrates of the ores are prepared by conventional means such...

C. M. Flynn T. G. Carnahan

1982-01-01

22

High performance liquid chromatography inductively coupled plasma mass spectrometry for speciation of arsenic compounds in urine  

Microsoft Academic Search

Speciation of urinary arsenic is very important to know the extent of human exposure to inorganic arsenic and also from toxicity point of view. A high performance liquid chromatography inductively coupled plasma mass spectrometry (HPLC-ICP-MS) system for speciation of arsenite, arsenate, monomethyl arsonic acid (MMAA), dimethyl arsenic acid (DMAA) and arsenobetaine (AB) in a single run in urine samples has

Gautam Samanta; Uttam K. Chowdhury; Badal K. Mandal; Dipankar Chakraborti; N. Chandra Sekaran; Hiroshi Tokunaga; Masanori Ando

2000-01-01

23

Biomonitoring of arsenic in urine and saliva of children playing on playgrounds constructed from chromated copper arsenate-treated wood.  

PubMed

Children may be exposed to arsenic during contact with structures treated with chromated copper arsenate (CCA). A high frequency of hand-to-mouth activity may increase their risk of ingesting arsenic. Previous work showed that arsenic concentrations in the hand-wash samples of children playing on CCA playgrounds were four times higher than those playing on non-CCA playgrounds. It is not clear whether playing on CCA playgrounds results in elevated overall exposure to arsenic. The objective of this study was to perform arsenic biomonitoring in children to determine whether playing on CCA-treated playgrounds substantially contributes to their overall exposure to arsenic. One hundred and twenty five saliva samples from 61 children and 101 urine samples from 45 children were collected after children played on 8 CCA and 8 non-CCA playgrounds. Arsenic speciation analysis was conducted using high performance liquid chromatography combined with inductively coupled plasma mass spectrometry. The arsenic species detected in the urine and saliva samples from children playing on CCA and non-CCA playgrounds were similar. Dimethylarsinic acid and arsenobetaine were the main arsenic species found in urine samples. The sum of inorganic trivalent and pentavalent arsenic, monomethylarsonic acid, and dimethylarsinic acid in urine was 15 +/- 28 microg/L in the CCA group and 12 +/- 23 microg/L in the non-CCA group (p = 0.60). The sum of these species in saliva was 1.1 +/- 2.1 microg/L in the CCA group and 1.4 +/- 1.1 microg/L in the non-CCA group (p = 0.32). These results show that there is no significant difference in the concentration or speciation of arsenic between the samples from children playing on CCA and non-CCA playgrounds. Contact with CCA playgrounds is not likely to significantly contribute to the overall arsenic exposure in children; other sources such as dietary arsenic may be a main contributor to their overall exposure. PMID:20377243

Lew, Kristi; Acker, Jason P; Gabos, Stephan; Le, X Chris

2010-05-15

24

Effects of Arsenic Concentrations and Forms on Arsenic Uptake by the Hyperaccumulator Ladder Brake  

Microsoft Academic Search

in plants, animals, and humans (Fowler, 1983). Remedi- ation of arsenic-contaminated soils has thus become a Ladder brake (Pteris vittata L.) is a newly discovered arsenic major environmental issue. hyperaccumulator. No information is available about arsenic effects on ladder brake. This study determined the effects of different arsenic Current remediation methods for arsenic-contami- concentrations (50 to 1000 mg kg

Cong Tu; Lena Q. Ma

2002-01-01

25

Development and application of a robust speciation method for determination of six arsenic compounds present in human urine.  

PubMed Central

Six arsenic species [arsenate, arsenite, arsenocholine, arsenobetaine, monomethyl arsonic acid, and dimethyl arsinic acid] present in human urine were determined using ion-exchange chromatography combined with inductively coupled plasma mass spectrometry (IC-ICP-MS). Baseline separation was achieved for all six species as well as for the internal standard (potassium hexahydroxy antimonate V) in a single chromatographic run of less than 30 min, using an ammonium carbonate buffer gradient (between 10 and 50 mM) at ambient temperature, in conjunction with cation- and anion-exchange columns in series. The performance of the method was evaluated with respect to linearity, precision, accuracy, and detection limits. This method was applied to determine the concentration of these six arsenic species in human urine samples (n = 251) collected from a population-based exposure assessment survey. Method precision was demonstrated by the analysis of duplicate samples that were prepared over a 2-year analysis period. Total arsenic was also determined for the urine samples using flow injection analysis coupled to ICP-MS. The summed concentration of the arsenic species was compared with the measured arsenic total to demonstrate mass balance.

Milstein, Lisa S; Essader, Amal; Pellizzari, Edo D; Fernando, Reshan A; Raymer, James H; Levine, Keith E; Akinbo, Olujide

2003-01-01

26

Development and application of a robust speciation method for determination of six arsenic compounds present in human urine.  

PubMed

Six arsenic species [arsenate, arsenite, arsenocholine, arsenobetaine, monomethyl arsonic acid, and dimethyl arsinic acid] present in human urine were determined using ion-exchange chromatography combined with inductively coupled plasma mass spectrometry (IC-ICP-MS). Baseline separation was achieved for all six species as well as for the internal standard (potassium hexahydroxy antimonate V) in a single chromatographic run of less than 30 min, using an ammonium carbonate buffer gradient (between 10 and 50 mM) at ambient temperature, in conjunction with cation- and anion-exchange columns in series. The performance of the method was evaluated with respect to linearity, precision, accuracy, and detection limits. This method was applied to determine the concentration of these six arsenic species in human urine samples (n = 251) collected from a population-based exposure assessment survey. Method precision was demonstrated by the analysis of duplicate samples that were prepared over a 2-year analysis period. Total arsenic was also determined for the urine samples using flow injection analysis coupled to ICP-MS. The summed concentration of the arsenic species was compared with the measured arsenic total to demonstrate mass balance. PMID:12611657

Milstein, Lisa S; Essader, Amal; Pellizzari, Edo D; Fernando, Reshan A; Raymer, James H; Levine, Keith E; Akinbo, Olujide

2003-03-01

27

Arsenic speciation analysis of human urine using ion exchange chromatography coupled to inductively coupled plasma mass spectrometry.  

PubMed

A sensitive and robust method for the determination of seven inorganic and organic arsenic species was developed using ion exchange chromatography combined with inductively coupled plasma mass spectrometry (IC-ICP-MS). Both anion and cation exchange columns were used in a complementary fashion. Arsenite (As(III)), arsenate (As(V)), monomethylarsonic acid (MMA(V)) and dimethylarsinic acid (DMA(V)) were selectively separated by an anion exchange column using sodium hydroxide (NaOH) gradient elution, while monomethylarsonous acid (MMA(III)), dimethylarsinous acid (DMA(III)) and arsenobetaine (AsB) were separated by a cation exchange column using 70 mM nitric acid as the mobile phase. Baseline separation, high repeatability and low detection limits (0.10-0.75 ng mL(-1)) were achieved. The spiked urine samples were analyzed with this method to evaluate the matrix effect on the method. The results suggest 1-10 dilutions should be made to urine samples before sample injection for the anion exchange analysis to minimize the matrix effect. To validate the method, a new standard reference material (NIST SRM-2670a) was also analyzed. The arsenic species in NIST SRM-2670a were determined by this method, and the sum of their concentrations agreed well with the total arsenic content certified for NIST SRM-2670a. Moreover, this method was applied to measure arsenic species in urine samples from one subject living in New Jersey who drank well water contaminated with arsenic. By this method, two key arsenic metabolites, MMA(III) and DMA(III), were found to be present in these urine samples, which has previously been rarely reported. PMID:17723711

Xie, Ruimin; Johnson, Willie; Spayd, Steve; Hall, Gene S; Buckley, Brian

2006-09-25

28

Urinary Arsenic Concentrations and their Associated Factors in Korean Adults  

PubMed Central

Arsenic (As) is a well-known human carcinogen and its dietary exposure has been found to be the major route of entry into general population. This study was performed to assess the body levels of As and their associated factors in Korean adults by analyzing total As in urine. Urine and blood samples were collected from 580 adults aged 20 years and older, who had not been exposed to As occupationally. Demographic information was collected with the help of a standard questionnaire, including age, smoking, alcohol intake, job profiles, and diet consumed in the last 24 hrs of the study. Total As, sum of As(III), As(V), monomethylarsonic acid (MMA), dimethylarsinic acid (DMA), in urine was determined using atomic absorption spectrometer involving hydride generation method. The geometric mean concentration of total As in urine was 7.10 ?g/L. Urine As was significantly higher in men (7.63 ?g/L) than in women (6.75 ?g/ L). Age, smoking, alcohol consumption, and job profiles of study subjects did not significantly affect the concentration of As in urine. No significant relationship was observed between body mass index (BMI), Fe, and total cholesterol in serum and urinary As. Urine As level was positively correlated with seaweeds, fishes & shellfishes, and grain intake. A negative correlation between urinary As level and HDL-cholesterol in serum and meat intake was observed. Overall, these results suggest that urinary As concentration could be affected by seafood consumption. Therefore, people who frequently consume seafood and grain need to be monitored for chronic dietary As exposure.

Bae, Hye-Sun; Ryu, Doug-Young; Choi, Byung-Sun

2013-01-01

29

Determination of arsenic in urine by atomic absorption spectrophotometry for biological monitoring of occupational exposure to arsenic  

Microsoft Academic Search

An atomic absorption spectrophotometric (AAS) method was successfully applied to analysis of urine for arsenic (As) as a measure of biological monitoring of occupational exposure to As in Vietnam. The application of the method to urine samples from 75 non-exposed control urbanites (after 2-day abstinence from sea foods) gave a reference level of 62.4±11.6 ?g\\/l (as mean±S.D.), from which the

T. M. N Dang; Q. T Tran; K. V Vu

1999-01-01

30

Arsenic species and selected metals in human urine: validation of HPLC/ICPMS and ICPMS procedures for a long-term population-based epidemiological study  

PubMed Central

Exposure to high inorganic arsenic concentrations in drinking water has been related to detrimental health effects, including cancers and possibly cardiovascular disease, in many epidemiological studies. Recent studies suggest that arsenic might elicit some of its toxic effects also at lower concentrations. The Strong Heart Study, a large epidemiological study of cardiovascular disease in American Indian communities, collected urine samples and performed medical examinations on 4,549 participants over a 10-year period beginning in 1989. We used anion-exchange HPLC/ICPMS to determine concentrations of arsenic species (methylarsonate, dimethylarsinate and arsenate) in 5,095 urine samples from the Strong Heart Study. We repeated the chromatography on a portion of the urine sample that had been oxidised, by addition of H2O2, to provide additional information on the presence of As(III) species and thio-arsenicals, and by difference, of arsenobetaine and other non-retained cations. Total concentrations for As, Cd, Mo, Pb, Sb, Se, U, W, and Zn were also determined in the urine samples by ICPMS. The dataset will be used to evaluate the relationships between the concentrations of urinary arsenic species and selected metals with various cardiometabolic health endpoints. We present and discuss the analytical protocol put in place to produce this large and valuable dataset.

Scheer, Jurgen; Findenig, Silvia; Goessler, Walter; Francesconi, Kevin A.; Howard, Barbara; Umans, Jason G.; Pollak, Jonathan; Tellez-Plaza, Maria; Silbergeld, Ellen K; Guallar, Eliseo; Navas-Acien, Ana

2012-01-01

31

Diet and toenail arsenic concentrations in a New Hampshire population with arsenic-containing water  

PubMed Central

Background Limited data exist on the contribution of dietary sources of arsenic to an individual’s total exposure, particularly in populations with exposure via drinking water. Here, the association between diet and toenail arsenic concentrations (a long-term biomarker of exposure) was evaluated for individuals with measured household tap water arsenic. Foods known to be high in arsenic, including rice and seafood, were of particular interest. Methods Associations between toenail arsenic and consumption of 120 individual diet items were quantified using general linear models that also accounted for household tap water arsenic and potentially confounding factors (e.g., age, caloric intake, sex, smoking) (n = 852). As part of the analysis, we assessed whether associations between log-transformed toenail arsenic and each diet item differed between subjects with household drinking water arsenic concentrations <1 ?g/L versus ?1 ?g/L. Results As expected, toenail arsenic concentrations increased with household water arsenic concentrations. Among the foods known to be high in arsenic, no clear relationship between toenail arsenic and rice consumption was detected, but there was a positive association with consumption of dark meat fish, a category that includes tuna steaks, mackerel, salmon, sardines, bluefish, and swordfish. Positive associations between toenail arsenic and consumption of white wine, beer, and Brussels sprouts were also observed; these and most other associations were not modified by exposure via water. However, consumption of two foods cooked in water, beans/lentils and cooked oatmeal, was more strongly related to toenail arsenic among those with arsenic-containing drinking water (?1 ?g/L). Conclusions This study suggests that diet can be an important contributor to total arsenic exposure in U.S. populations regardless of arsenic concentrations in drinking water. Thus, dietary exposure to arsenic in the US warrants consideration as a potential health risk.

2013-01-01

32

Total arsenic concentrations in toenails quantified by two techniques provide a useful biomarker of chronic arsenic exposure in drinking water  

SciTech Connect

Accurate quantitation of any contaminant of interest is critical for exposure assessment and metabolism studies that support risk assessment. A preliminary step in an arsenic exposure assessment study in Nevada quantified total arsenic (TAs) concentrations in tissues as biomarkers of exposure. Participants in this study (n=95) were at least 45 years old, had lived in the area for more than 20 years, and were exposed to a wide range of arsenic concentrations in drinking water (3-2100ppb). Concentrations of TAs in blood, urine, and toenails determined by hydride generation-atomic fluorescence spectrometry (HG-AFS) ranged from below detection to 0.03, 0.76, and 12ppm, respectively; TAs in blood rarely exceeded the limit of detection. For comparison, TAs in toenails determined by neutron activation analysis (NAA) ranged from below detection to 16ppm. Significant (P<0.0001) positive regressions were seen between the TAs concentration in toenails and in drinking water (adjusted r{sup 2}=0.3557 HG-AFS, adjusted r{sup 2}=0.3922 NAA); TAs concentrations in urine were not described by drinking water As (adjusted r{sup 2}=0.0170, P=0.1369). Analyses of TAs in toenails by HGAFS and NAA yielded highly concordant estimates (r=0.7977, P<0.0001). These results suggest that toenails are a better biomarker of chronic As exposure than urine in the current study, because the sequestration of As in toenails provides an integration of exposure over time that does not occur in urine.

Adair, Blakely M. [Experimental Toxicology Division, National Health and Environmental Effects Research Laboratory, Office of Research and Development, United States Environmental Protection Agency, Research Triangle Park, North Carolina (United States)]. E-mail: adair.blakely@epa.gov; Hudgens, Edward E. [Human Studies Division, National Health and Environmental Effects Research Laboratory, Office of Research and Development, United States Environmental Protection Agency, Research Triangle Park, North Carolina (United States); Schmitt, Michael T. [Human Studies Division, National Health and Environmental Effects Research Laboratory, Office of Research and Development, United States Environmental Protection Agency, Research Triangle Park, North Carolina (United States); Calderon, Rebecca L. [Human Studies Division, National Health and Environmental Effects Research Laboratory, Office of Research and Development, United States Environmental Protection Agency, Research Triangle Park, North Carolina (United States); Thomas, David J. [Experimental Toxicology Division, National Health and Environmental Effects Research Laboratory, Office of Research and Development, United States Environmental Protection Agency, Research Triangle Park, North Carolina (United States)

2006-06-15

33

Chronic arsenic exposure increases TGFalpha concentration in bladder urothelial cells of Mexican populations environmentally exposed to inorganic arsenic  

SciTech Connect

Inorganic arsenic (iAs) is a well-established carcinogen and human exposure has been associated with a variety of cancers including those of skin, lung, and bladder. High expression of transforming growth factor alpha (TGF-{alpha}) has associated with local relapses in early stages of urinary bladder cancer. iAs exposures are at least in part determined by the rate of formation and composition of iAs metabolites (MAs{sup III}, MAs{sup V}, DMAs{sup III}, DMAs{sup V}). This study examines the relationship between TGF-{alpha} concentration in exfoliated bladder urothelial cells (BUC) separated from urine and urinary arsenic species in 72 resident women (18-51 years old) from areas exposed to different concentrations of iAs in drinking water (2-378 ppb) in central Mexico. Urinary arsenic species, including trivalent methylated metabolites were measured by hydride generation atomic absorption spectrometry method. The concentration of TGF-{alpha} in BUC was measured using an ELISA assay. Results show a statistically significant positive correlation between TGF-{alpha} concentration in BUC and each of the six arsenic species present in urine. The multivariate linear regression analyses show that the increment of TGF-{alpha} levels in BUC was importantly associated with the presence of arsenic species after adjusting by age, and presence of urinary infection. People from areas with high arsenic exposure had a significantly higher TGF-{alpha} concentration in BUC than people from areas of low arsenic exposure (128.8 vs. 64.4 pg/mg protein; p < 0.05). Notably, exfoliated cells isolated from individuals with skin lesions contained significantly greater amount of TGF-{alpha} than cells from individuals without skin lesions: 157.7 vs. 64.9 pg/mg protein (p = 0.003). These results suggest that TGF-{alpha} in exfoliated BUC may serve as a susceptibility marker of adverse health effects on epithelial tissue in arsenic-endemic areas.

Valenzuela, Olga L. [Seccion de Toxicologia, Cinvestav-IPN, Av. Instituto Politecnico Nacional 2508, Col. Zacatenco, CP 07300, Mexico D.F. (Mexico); Germolec, Dori R. [Environmental Immunology and Neurobiology Section, NIH, Research Triangle Park, NC 27709 (United States); Borja-Aburto, Victor H. [Salud en el Trabajo, Instituto Mexicano del Seguro Social, Mexico DF (Mexico); Contreras-Ruiz, Jose [Division de Dermatologia, Hospital General Dr. Manuel Gea Gonzalez, Mexico, D.F. (Mexico); Garcia-Vargas, Gonzalo G. [Facultad de Medicina, Universidad Juarez del Estado de Durango, Gomez Palacio, Durango (Mexico); Razo, Luz M. del [Seccion de Toxicologia, Cinvestav-IPN, Av. Instituto Politecnico Nacional 2508, Col. Zacatenco, CP 07300, Mexico D.F. (Mexico)], E-mail: ldelrazo@cinvestav.mx

2007-08-01

34

The Case for Visual Analytics of Arsenic Concentrations in Foods  

PubMed Central

Arsenic is a naturally occurring toxic metal and its presence in food could be a potential risk to the health of both humans and animals. Prolonged ingestion of arsenic contaminated water may result in manifestations of toxicity in all systems of the body. Visual Analytics is a multidisciplinary field that is defined as the science of analytical reasoning facilitated by interactive visual interfaces. The concentrations of arsenic vary in foods making it impractical and impossible to provide regulatory limit for each food. This review article presents a case for the use of visual analytics approaches to provide comparative assessment of arsenic in various foods. The topics covered include (i) metabolism of arsenic in the human body; (ii) arsenic concentrations in various foods; (ii) factors affecting arsenic uptake in plants; (ii) introduction to visual analytics; and (iv) benefits of visual analytics for comparative assessment of arsenic concentration in foods. Visual analytics can provide an information superstructure of arsenic in various foods to permit insightful comparative risk assessment of the diverse and continually expanding data on arsenic in food groups in the context of country of study or origin, year of study, method of analysis and arsenic species.

Johnson, Matilda O.; Cohly, Hari H.P.; Isokpehi, Raphael D.; Awofolu, Omotayo R.

2010-01-01

35

Association between arsenic exposure from a coal-burning power plant and urinary arsenic concentrations in Prievidza District, Slovakia.  

PubMed Central

To assess the arsenic exposure of a population living in the vicinity of a coal-burning power plant with high arsenic emission in the Prievidza District, Slovakia, 548 spot urine samples were speciated for inorganic As (Asinorg), monomethylarsonic acid (MMA), dimethylarsinic acid (DMA), and their sum (Assum). The urine samples were collected from the population of a case-control study on nonmelanoma skin cancer (NMSC). A total of 411 samples with complete As speciations and sufficient urine quality and without fish consumption were used for statistical analysis. Although current environmental As exposure and urinary As concentrations were low (median As in soil within 5 km distance to the power plant, 41 micro g/g; median urinary Assum, 5.8 microg/L), there was a significant but weak association between As in soil and urinary Assum(r = 0.21, p < 0.01). We performed a multivariate regression analysis to calculate adjusted regression coefficients for environmental As exposure and other determinants of urinary As. Persons living in the vicinity of the plant had 27% higher Assum values (p < 0.01), based on elevated concentrations of the methylated species. A 32% increase of MMA occurred among subjects who consumed homegrown food (p < 0.001). NMSC cases had significantly higher levels of Assum, DMA, and Asinorg. The methylation index Asinorg/(MMA + DMA) was about 20% lower among cases (p < 0.05) and in men (p < 0.05) compared with controls and females, respectively.

Ranft, Ulrich; Miskovic, Peter; Pesch, Beate; Jakubis, Pavel; Fabianova, Elenora; Keegan, Tom; Hergemoller, Andre; Jakubis, Marian; Nieuwenhuijsen, Mark J

2003-01-01

36

Arsenic Concentrations and Speciation in Shellfishes from Korea  

NASA Astrophysics Data System (ADS)

Speciation of arsenic has received significant attention over the past 20 years in both mechanistic and exposure assessment research. Because the toxicity of arsenic is related to its oxidation state and its chemical forms, the determination of the total arsenic contents in a sample is not adequate to allow its impact on living organisms to be estimated. The inorganic arsenic species, arsenite (As3+) and arsenate (As5+), have been classified as carcinogenic and the methylated forms, monomethyl arsonic acid (MMA) and dimethyl arsinic acid (DMA) have recently been identified as cancer promoters. The highly methylated compounds like as arsenobetaine (AsB) and arsenocholine (AsC) are considered to be nontoxic. Although organisms in marine environment contain high amounts of total arsenic (ppm level), it is not usually present as inorganic arsenic or simple methylated forms well known as one of the toxic species. Arsenobetaine is the dominant species in marine animals and arsenosugars are most abundant in marine algae. This study aims to clarify those arsenic species present in the whole body of eleven different shellfishes from Korea. And those arsenic species were separated and measured by characterization using high performance liquid chromatography-inductively coupled plasma-mass spectrometry (HPLC-ICP-MS) coupled system. The separation of arsenic species was achieved on anion exchange column and cation exchange column using phosphate and pyridine eluent, respectively. The ultrasonic extraction was employed for extraction of arsenic from whole body of shellfishes. The method was validated by analyzing three certified reference materials (DORM-2, TORT-2, 1566b). Total arsenic concentrations ranged from 0.1 mg/kg dry mass to 21.7 mg/kg dry mass. Most marine shellfishes contained higher arsenobetaine and arsenocholine with the exception of two shellfishes living in river. The lower amounts of inorganic arsenic species were also found in the some sample extracts. Detection of inorganic arsenic can be explained by the conversion of inorganic arsenic to organic arsenic compounds in digestion system in the body may be occurring.

Yoon, C.; Yoon, H.

2005-12-01

37

Processing of Cobalt-Copper-Arsenic Complex Ore Concentrate  

Microsoft Academic Search

Extraction of cobalt from complex ore flotation concentrates obtained from the Blackbird Mine. Idaho. USA is reviewed. After flotation of a primary copper concentrate, a bulk concentrate is recovered containing major amounts of cobalt, arsenic, and iron, with minor amounts of copper and nickel. This concentrate can be upgraded during flotation by removing iron, but with considerable cobalt loss. Chemical

ROBERT W. BARTLETT

1995-01-01

38

Rice consumption and urinary concentrations of arsenic in US adults.  

PubMed

Exposure to inorganic arsenic in the general population occurs mainly from drinking water and food sources. This study examined the association between rice consumption and urinary concentrations of arsenic in US adults, aged 20-85 years, in the 2003-2006 National Health and Nutrition Examination Survey. Significantly higher geometric means of creatinine-corrected urinary concentrations of total arsenic (TAs) and dimethylarsinic acid (DMA) were found in participants who consumed rice more than twice per week, compared to the reference group. Multivariate logistic regression analysis revealed a statistically significant association between rice consumption and urinary concentrations of TAs [odds ratio (OR) = 1.51 (1.08, 2.09)] and DMA [OR = 2.24 (1.57, 3.21)] after adjustment for demographic variables, seafood intake (the main source of organic arsenic), and source of drinking water. Furthermore, significant variations in rice consumption and urinary concentrations of arsenic were observed in different racial groups. This study demonstrated that rice consumption contributed to inorganic arsenic exposure in US adults. PMID:24236891

Wei, Yudan; Zhu, Jianmin; Nguyen, An

2014-10-01

39

Investigation of Arsenic Exposure from Soil at a Superfund Site  

Microsoft Academic Search

The purpose of this study was to determine if significant arsenic exposure was occurring at a Superfund site with elevated surface soil arsenic concentrations. A second objective was to determine the statistical relationship between the various methods of measuring arsenic exposure in humans. Random urine, 24-hr urine, hair, and fingernail samples were collected at the end of the workweek from

D. J. Hewitt; G. C. Millner; A. C. Nye; H. F. Simmons

1995-01-01

40

Dietary B vitamin intakes and urinary total arsenic concentration in the Health Effects of Arsenic Longitudinal Study (HEALS) cohort, Bangladesh  

Microsoft Academic Search

Purpose  The objective of this analysis was to evaluate the effects of dietary B vitamin intakes on creatinine-adjusted urinary total\\u000a arsenic concentration among individuals participating in the Health Effects of Arsenic Longitudinal Study (HEALS) cohort in\\u000a Araihazar, Bangladesh. Arsenic exposure is a major public health problem in Bangladesh, where nearly 77 million people have\\u000a been chronically exposed to arsenic through the consumption

Maria Argos; Paul J. Rathouz; Brandon L. Pierce; Tara Kalra; Faruque Parvez; Vesna Slavkovich; Alauddin Ahmed; Yu Chen; Habibul Ahsan

2010-01-01

41

Prognostic Value of Plasma and Urine Paraquat Concentration  

Microsoft Academic Search

1 A non-exponential mathematical equation was used to extrapolate the 'predictive line' for plasma paraquat concentrations beyond 24 h. Plasma paraquat concentrations were measured in 30 patients who were admitted more than 24 h after overdose. The extrapolated line accurately predicted the outcome in 27 of these 30 patients.2 Urine paraquat concentrations were measured in 53 patients. All patients with

J. M. Scherrmann; P. Houze; C. Bismuth; R. Bourdon

1987-01-01

42

Routine clinical determination of lead, arsenic, cadmium, and thallium in urine and whole blood by inductively coupled plasma mass spectrometry  

Microsoft Academic Search

For the measurement of As, Cd, Pb, and Tl in urine or whole blood, judicious choices of internal standard elements for matrix correction and the development of a refined isobaric arsenic correction are necessary to produce accurate ICP-MS results. Ga and Rh are chosen as internal standards for As and Cd respectively. Bi is better for the correction of Pb

David E. Nixon; Thomas P. Moyer

1996-01-01

43

Urine naloxone concentration at different phases of buprenorphine maintenance treatment.  

PubMed

In spite of the benefits of buprenorphine-naloxone co-formulation (BNX) in opioid maintenance treatment, the naloxone component has not prevented parenteral use of BNX. Current laboratory methods are not sufficient to differentiate between therapeutic and illicit use of buprenorphine, and little is known about urine naloxone concentrations. Measurement of urine naloxone, together with buprenorphine and norbuprenorphine, might help to determine the naloxone source and administration route. A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and validated for this purpose. Naloxone, buprenorphine, and norbuprenorphine total concentrations were measured in urine samples from opioid-dependent patients before and during stable and unstable phases of maintenance treatment with BNX. The limit of quantification in urine was 1.0?µg/L for naloxone, buprenorphine and norbuprenorphine. Before treatment, all samples contained buprenorphine but the median naloxone concentration was 0?µg/L. During the maintenance treatment with BNX all urine samples were positive for naloxone, buprenorphine and norbuprenorphine. The naloxone concentration at a stable phase of treatment (median 60?µg/L, range 5-200?µg/L) was not different from the naloxone concentration at an unstable phase (70?µg/L, 10-1700?µg/L). Applying an upper limit of 200?µg/L to the sample, the median naloxone/buprenorphine ratio was higher in the high than in the low naloxone concentration group (0.9 vs 0.3, respectively). This study suggests that naloxone in urine can act as an indicator of compliance with BNX. Parenteral use of BNX was associated with a high naloxone/buprenorphine ratio. Negative naloxone with positive buprenorphine suggests the use/abuse of buprenorphine alone. PMID:23512803

Heikman, Pertti; Häkkinen, Margareeta; Gergov, Merja; Ojanperä, Ilkka

2014-03-01

44

Serum and urine chromium concentrations in elderly diabetics  

Microsoft Academic Search

The serum and urine chromium concentrations of 57 diabetics and 55 normal fasting subjects were determined by atomic absorption\\u000a spectrometry (AAS). Our results indicate that the chromium concentration ranges of serum and urine for diabetics are 0.22–0.36\\u000a and 4.54–5.90 ?g\\/L, respectively, significantly lower than 0.66–0.84 7.80–9.68 ?g\\/L for the normal (P<0.001), which implies that the elderly diabetics probably lack chromium.

Wenjun Ding; Zhifang Chai; Peng Duan; Weiyue Feng; Qinfang Qian

1998-01-01

45

Arsenic  

MedlinePLUS

... high-arsenic and low-arsenic sources. For example, test water for arsenic levels and paint tube wells or ... education. Blend low-arsenic water with higher-arsenic water to achieve an acceptable ... absorption, ion exchange and membrane techniques. There is an ...

46

HEALTH EFFECTS OF CHRONIC EXPOSURE TO ARSENIC VIA DRINKING WATER IN INNER MONGOLIA: IV. DISTRIBUTION OF ARSENIC CONCENTRATIONS IN WELLS  

EPA Science Inventory

HEALTH EFFECTS OF CHRONIC EXPOSURE TO ARSENIC VIA DRINKING WATER IN INNER MONGOLIA: IV. DISTRIBUTION OF ARSENIC CONCENTRATIONS IN WELLS Zhixiong Ning, B.S., Zhiyi Liu,B.S., Shiying Zhang, B.S., Chenglong Ma, B.S., Inner Mongolia Ba Men Anti-epidemic Station, Michael Ri...

47

Arsenic  

MedlinePLUS

... and minerals. Arsenic compounds are used to preserve wood, as pesticides, and in some industries. Arsenic can ... Breathing sawdust or burning smoke from arsenic-treated wood Living in an area with high levels of ...

48

Spatial and Temporal Variations in Arsenic Exposure via Drinking-water in Northern Argentina  

PubMed Central

This study evaluated the spatial, temporal and inter-individual variations in exposure to arsenic via drinking-water in Northern Argentina, based on measurements of arsenic in water, urine, and hair. Arsenic concentrations in drinking-water varied markedly among locations, from <1 to about 200 ?g/L. Over a 10-year period, water from the same source in San Antonio de los Cobres fluctuated within 140 and 220 ?g/L, with no trend of decreasing concentration. Arsenic concentrations in women's urine (3–900 ?g/L, specific weight 1.018 g/mL) highly correlated with concentrations in water on a group level, but showed marked variations between individuals. Arsenic concentrations in hair (range 20–1,500 ?g/kg) rather poorly correlated with urinary arsenic, possibly due to external contamination. Thus, arsenic concentration in urine seems to be a better marker of individual arsenic exposure than concentrations in drinking-water and hair.

Concha, Gabriela; Nermell, Barbro

2006-01-01

49

Blank values, adsorption, pre-concentration, and sample preservation for arsenic speciation of environmental water samples  

Microsoft Academic Search

Arsenic is the focus of public attention because of its toxicity. Arsenic analysis, its toxicity, and its fate in the environment have been broadly studied, still its blank values, adsorption to sampling materials and pre-concentration of water samples as well as stabilization of arsenic compounds in water samples under field conditions have been very little investigated. In this study, we

Jen-How Huang; Gunter Ilgen

2004-01-01

50

Arsenic methylation patterns before and after changing from high to lower concentrations of arsenic in drinking water.  

PubMed Central

Inorganic arsenic (In-As), an occupational and environmental human carcinogen, undergoes biomethylation to monomethylarsonate (MMA) and dimethylarsinate (DMA). It has been proposed that saturation of methylation capacity at high exposure levels may lead to a threshold for the carcinogenicity of In-As. The relative distribution of urinary In-As, MMA, and DMA is used as a measure of human methylation capacity. The most common pathway for elevated environmental exposure to In-As worldwide is through drinking water. We conducted a biomarker study in northern Chile of a population chronically exposed to water naturally contaminated with high arsenic content (600 micrograms/l). In this paper we present the results of a prospective follow-up of 73 exposed individuals, who were provided with water of lower arsenic content (45 micrograms/l) for 2 months. The proportions of In-As, MMA, and DMA in urine were compared before and after intervention, and the effect of other factors on the distribution of arsenic metabolites was also analyzed. The findings of this study indicate that the decrease in arsenic exposure was associated with a small decrease in the percent In-As in urine (from 17.8% to 14.6%) and in the MMA/DMA ratio (from 0.23 to 0.18). Other factors such as smoking, gender, age, years of residence, and ethnicity were associated mainly with changes in the MMA/DMA ratio, with smoking having the strongest effect. Nevertheless, the factors investigated accounted for only about 20% of the large interindividual variability observed. Genetic polymorphisms in As-methylating enzymes and other co-factors are likely to contribute to some of the unexplained variation. The changes observed in the percent In-As and in the MMA/DMA ratio do not support an exposure-based threshold for arsenic methylation in humans. Images Figure 1. A Figure 1. B Figure 2. A Figure 2. B

Hopenhayn-Rich, C; Biggs, M L; Kalman, D A; Moore, L E; Smith, A H

1996-01-01

51

Well characteristics influencing arsenic concentrations in ground water  

Microsoft Academic Search

Naturally occurring arsenic contamination is common in ground water in the upper Midwest. Arsenic is most likely to be present in glacial drift and shallow bedrock wells that lie within the footprint of northwest provenance Late Wisconsinan glacial drift. Elevated arsenic is more common in domestic wells and in monitoring wells than it is in public water system wells. Arsenic

Melinda L. Erickson; Randal J. Barnes

2005-01-01

52

Predicting arsenic concentrations in porewaters of buried uranium mill tailings  

SciTech Connect

The proposed JEB Tailings Management Facility (TMF) to be emplaced below the groundwater table in northern Saskatchewan, Canada, will contain uranium mill tailings from McClean Lake, Midwest and Cigar Lake ore bodies, which are high in arsenic (up to 10%) and nickel (up to 5%). A serious concern is the possibility that high arsenic and nickel concentrations may be released from the buried tailings, contaminating adjacent groundwaters and a nearby lake. Laboratory tests and geochemical modeling were performed to examine ways to reduce the arsenic and nickel concentrations in TMF porewaters so as to minimize such contamination from tailings buried for 50 years and longer. The tests were designed to mimic conditions in the mill neutralization circuit (3 hr tests at 25 C), and in the TMF after burial (5--49 day aging tests). The aging tests were run at 50, 25 and 4 C (the temperature in the TMF). In order to optimize the removal of arsenic by adsorption and precipitation, ferric sulfate was added to tailings raffinates having Fe/As ratios of less than 3--5. The acid raffinates were then neutralized by addition of slaked lime to nominal pH values of 7, 8, or 9. Analysis and modeling of the test results showed that with slaked lime addition to acid tailings raffinates, relatively amorphous scorodite (ferric arsenate) precipitates near pH 1, and is the dominant form of arsenate in slake limed tailings solids except those high in Ni and As and low in Fe, in which cabrerite-annabergite (Ni, Mg, Fe(II) arsenate) may also precipitate near pH 5--6. In addition to the arsenate precipitates, smaller amounts of arsenate are also adsorbed onto tailings solids. The aging tests showed that after burial of the tailings, arsenic concentrations may increase with time from the breakdown of the arsenate phases (chiefly scorodite). However, the tests indicate that the rate of change decreases and approaches zero after 72 hrs at 25 C, and may equal zero at all times in the TMF at 4 C. Consistent with a kinetic model that describes the rate of breakdown of scorodite to form hydrous ferric oxide, the rate of release of dissolved arsenate to tailings porewaters from slake limed tailings: (1) is proportional to pH above pH 6--7; (2) decreases exponentially as the total molar Fe/As ratio of tailings raffinates is increased from 1/1 to greater than 5/1; and (3) is proportional to temperature with an average Arrhenius activation energy of 13.4 {+-} 4.2 kcal/mol. Study results suggest that if ferric sulfate and slaked lime are added in the tailings neutralization circuit to give a raffinate Fe/As molar ratio of at least 3--5 and a nominal (initial) pH of 8 (final pH of 7--8), arsenic and nickel concentrations of 2 mg/L or less, are probable in porewaters of individual tailings in the TMF for 50 to 10,000 yrs after tailings disposal. However, the tailings will be mixed in the TMF, which will contain about 35% tailings with Fe/As = 3.0, and 65% tailings with Fe/As = 5.0--7.7. Thus, it seems likely that average arsenic pore water concentrations in the TMF may not exceed 1 mg/L.

Langmuir, D.; Mahoney, J.; MacDonald, A.; Rowson, J.

1999-10-01

53

Human exposure to arsenic from drinking water in Vietnam.  

PubMed

Vietnam is an agricultural country with a population of about 88 million, with some 18 million inhabitants living in the Red River Delta in Northern Vietnam. The present study reports the chemical analyses of 68 water and 213 biological (human hair and urine) samples conducted to investigate arsenic contamination in tube well water and human arsenic exposure in four districts (Tu Liem, Dan Phuong, Ly Nhan, and Hoai Duc) in the Red River Delta. Arsenic concentrations in groundwater in these areas were in the range of <1 to 632?g/L, with severe contamination found in the communities Ly Nhan, Hoai Duc, and Dan Phuong. Arsenic concentrations were markedly lowered in water treated with sand filters, except for groundwater from Hoai Duc. Human hair samples had arsenic levels in the range of 0.07-7.51?g/g, and among residents exposed to arsenic levels ?50?g/L, 64% of them had hair arsenic concentrations higher than 1?g/g, which is a level that can cause skin lesions. Urinary arsenic concentrations were 4-435?g/g creatinine. Concentrations of arsenic in hair and urine increased significantly with increasing arsenic content in drinking water, indicating that drinking water is a significant source of arsenic exposure for these residents. The percentage of inorganic arsenic (IA) in urine decreased with age, whereas the opposite trend was observed for monomethylarsonic acid (MMA) in urine. Significant co-interactions of age and arsenic exposure status were also detected for concentrations of arsenic in hair and the sum of IA, MMA, and dimethylarsinic acid (DMA) in urine and %MMA. In summary, this study demonstrates that a considerable proportion of the Vietnamese population is exposed to arsenic levels of chronic toxicity, even if sand filters reduce exposure in many households. Health problems caused by arsenic ingestion through drinking water are increasingly reported in Vietnam. PMID:24262873

Agusa, Tetsuro; Trang, Pham Thi Kim; Lan, Vi Mai; Anh, Duong Hong; Tanabe, Shinsuke; Viet, Pham Hung; Berg, Michael

2014-08-01

54

Can sample treatments based on advanced oxidation processes assisted by high-intensity focused ultrasound be used for toxic arsenic determination in human urine by flow-injection hydride-generation atomic absorption spectrometry?  

PubMed

Two advanced oxidation processes (AOPs), based on high-intensity focused ultrasound (HIFU), namely, KMnO(4)/HCl/HIFU and H(2)O(2)/HCl/HIFU are studied and compared for the determination of toxic arsenic in human urine [As(III)+As(V)+MMA+DMA] by flow-injection hydride-generation atomic absorption spectrometry (FI-HG-AAS). The KMnO(4)/HCl/HIFU procedure was found to be adequate for organic matter degradation in human urine. l-cysteine (letra minuscula) was used for As reduction to the trivalent state. The new procedure was assessed with seven urines certified in different As species. Results revealed that with KMnO(4)/HCl/HIFU plus l-cysteine the toxic arsenic can be accurately measured in human urine whilst the H(2)O(2)/HCl/HIFU procedure underestimates toxic As. DMA and MMA degradation in urine were observed, due to the effects of the ultrasonic field. Recoveries for As(III), As(V), MMA and DMA were within the certified ranges. Arsenobetaine was not degraded by the AOPs. The new procedure adheres well to the principles of analytical minimalism: (i) low reagent consumption, (ii) low reagent concentration, (iii) low waste production and (iv) low amount of time required for sample preparation and analysis. PMID:19071711

Correia, A; Galesio, M; Santos, H; Rial-Otero, R; Lodeiro, C; Oehmen, A; Conceiçăo, Antonio C L; Capelo, J L

2007-05-15

55

Determination of Arsenic Concentration in Well and Borehole Waters in Zaria, Nigeria  

Microsoft Academic Search

The objective of this research is to determine the concentration of arsenic in wells and boreholes water in Zaria, to see whether the concentration level is sufficient enough to affect the health of the people living in the area under study. In this study arsenic concentrations of sixty well and five bore hole water samples collected from Zaria and environs

H. Musa; I. A. Yakasai; K. Y. Musa; A. B. Isah; K. Mshelbwala

2008-01-01

56

Seasonal Variation of Arsenic Concentrations in Tubewells in West Bengal, India  

Microsoft Academic Search

This study was conducted to monitor the changes in arsenic concentration during different seasons in a one-year period during 2002-2003 in selected tubewells in an arsenic-affected area in the district of South 24 Parganas in West Bengal, India, and to map the location of the wells. Seasonal variations in concentrations of arsenic in water were measured from 74 selected tubewells,

Xavier Savarimuthu; Meera M. Hira-Smith; Yan Yuan; Ondine S. von Ehrenstein; Subhankar Das; Nilima Ghosh; D. N. Guha Mazumder; Allan H. Smith

2006-01-01

57

Mutagenicity studies with urine concentrates from coke plant workers  

SciTech Connect

Urine from coke plant workers, collected before and after work, were tested for the content of mutagenic substances in the Salmonella test system. Urine extracts from exposed smokers showed mutagenic activity, whereas urine from exposed nonsmokers did not. The mutagenicity of exposed smoker's urine was not significantly different from that of urine from nonexposed smokers. Mutagenicity of smokers' urine was only evident in the presence of a rat liver metabolic activation system. The addition of beta-glucuronidase did not enhance the mutagenic effect. The facts that coke plant workers are exposed to very high levels of polycyclic aromatic hydrocarbons (PAH) and that there is no observed enhanced mutagenicity of their urine indicate that the mutagenicity observed with urine from smokers is not due to conventional PAH.

Moeller, M.; Dybing, E.

1980-01-01

58

Impact of abandoned mine tailings on the arsenic concentrations in Moira Lake, Ontario  

Microsoft Academic Search

Arsenic has accumulated in the different compartments of Moira Lake for the last 160 years, since mining and mineral processing began in the area. The annual total fluvial input of arsenic (As) to the lake is approximately 3.5 tonnes. The dissolved As concentrations in the water show seasonal differences, with an average concentration of 62 ?g\\/L during the summer, and

Jose M. Azcue; Jerome O. Nriagu

1995-01-01

59

Pneumococcal C and type polysaccharide detection in the concentrated urine of patients with bacteremia  

Microsoft Academic Search

The C polysaccharide of Streptococcus pneumoniae was detected in the concentrated urine of 23 of 33 patients with pneumococcal bacteremia using latex agglutination. Type-specific polysaccharides were detected in the urine of 17 of these 33 patients including 4 patients lacking C polysaccharide in their urine. These 4 with the 23 detected above gave a total sensitivity of 82% (27\\/33). The

Kenneth Bromberg; Gaylene Tannis; Alma Rodgers

1990-01-01

60

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; Brantsćter, A L

2013-10-01

61

Investigation of arsenic exposure from soil at a superfund site.  

PubMed

The purpose of this study was to determine if significant arsenic exposure was occurring at a Superfund site with elevated surface soil arsenic concentrations. A second objective was to determine the statistical relationship between the various methods of measuring arsenic exposure in humans. Random urine, 24-hr urine, hair, and fingernail samples were collected at the end of the workweek from 40 employees at an active pesticide manufacturing facility which had formerly produced arsenical pesticides. There was no indication of adverse health effects among the employees attributable to arsenic exposure. Mean urinary, hair, and fingernail concentrations of arsenic were well within normal values and indicated that significant arsenic exposure was not occurring among the employees. Random and 24-hr urine measurements were significantly correlated. Hair and fingernail results also were significantly correlated. Urine results did not correlate well with hair or fingernail results. Results of this study suggest that although there may be some individual variation, random and 24-hr urine arsenic results are not substantially different. For the purpose of screening for arsenic exposure, random urine samples may be an adequate and preferable test for those populations in equilibrium with their environment. PMID:7601075

Hewitt, D J; Millner, G C; Nye, A C; Simmons, H F

1995-02-01

62

Concentration of mutagens from urine by absorption with the nonpolar resin XAD-2: cigarette smokers have mutagenic urine.  

PubMed Central

A method is described for concentrating mutagens/carcinogens from human urine about 200-fold for subsequent assay in the Salmonella/mammalian microsome mutagenicity test. The method is also applicable for other aqueous liquids and for other in vitro tests for mutagens/carcinogens. The urine (up to 500 ml) is put through a column with a 1.5-cm3 bed volume of XAD-2 (styrene-divinylbenzene polymer) and the adsorbed material is then eluted with a few milliliters of acetone. The acetone is taken to dryness and the residue is dissolved in dimethyl sulfoxide. This is the urine concentrate that is assayed for mutagenicity. Various mutagens/carcinogens have been added to human urine and the recoveries have been measured after adsorption on XAD-2, XAD-4, and Tenax GC (diphenyl-p-phenylene oxide polymer). We propose that this method be used in monitoring the urine of human populations and of experimental animals in toxicological studies. It is shown with this procedure that cigarette smokers have mutagenic urine while nonsmokers do not.

Yamasaki, E; Ames, B N

1977-01-01

63

Correlation of arsenic exposure through drinking groundwater and urinary arsenic excretion among adults in Pakistan.  

PubMed

Long-term exposure to arsenic has been associated with manifestation of skin lesions (melanosis/keratosis) and increased risk of internal cancers (lung/bladder). The objective of the study described here was to determine the relationship between exposure of arsenic through drinking groundwater and urinary arsenic excretion among adults > or =15 years of age living in Khairpur district, Pakistan. Total arsenic was determined in drinking groundwater and in spot urine samples of 465 randomly selected individuals through hydride generation-atomic absorption spectrometry. Spearman's rank correlation coefficient was calculated between arsenic in drinking groundwater and arsenic excreted in urine. The median arsenic concentration in drinking water was 2.1 microg/L (range: 0.1-350), and in urine was 28.5 microg/L (range: 0.1-848). Positive correlation was found between total arsenic in drinking water and in urine (r = .52, p < .01). Urinary arsenic may be used as a biomarker of arsenic exposure through drinking water. PMID:24645413

Ahmed, Mubashir; Fatmi, Zafar; Ali, Arif

2014-01-01

64

Predicting arsenic concentrations in groundwater of San Luis Valley, Colorado: implications for individual-level lifetime exposure assessment.  

PubMed

Consumption of inorganic arsenic in drinking water at high levels has been associated with chronic diseases. Risk is less clear at lower levels of arsenic, in part due to difficulties in estimating exposure. Herein we characterize spatial and temporal variability of arsenic concentrations and develop models for predicting aquifer arsenic concentrations in the San Luis Valley, Colorado, an area of moderately elevated arsenic in groundwater. This study included historical water samples with total arsenic concentrations from 595 unique well locations. A longitudinal analysis established temporal stability in arsenic levels in individual wells. The mean arsenic levels for a random sample of 535 wells were incorporated into five kriging models to predict groundwater arsenic concentrations at any point in time. A separate validation dataset (n = 60 wells) was used to identify the model with strongest predictability. Findings indicate that arsenic concentrations are temporally stable (r = 0.88; 95 % CI 0.83-0.92 for samples collected from the same well 15-25 years apart) and the spatial model created using ordinary kriging best predicted arsenic concentrations (? = 0.72 between predicted and observed validation data). These findings illustrate the value of geostatistical modeling of arsenic and suggest the San Luis Valley is a good region for conducting epidemiologic studies of groundwater metals because of the ability to accurately predict variation in groundwater arsenic concentrations. PMID:24429726

James, Katherine A; Meliker, Jaymie R; Buttenfield, Barbara E; Byers, Tim; Zerbe, Gary O; Hokanson, John E; Marshall, Julie A

2014-08-01

65

CONCENTRATIONS OF CADMIUM AND ARSENIC IN SEAFOOD FROM MUANG DISTRICT, RAYONG PROVINCE  

Microsoft Academic Search

This study was designed to determine the concentration of cadmium (Cd) and arsenic (As) in seafoods from Muang District, Rayong Province. Between January and February 2008, samples of the 13 most consumed seafood species were selected and randomly obtained from 3 local markets in Muang District of Rayong Province. Cadmium and arsenic levels were measured by atomic absorption spectrophotometry (AAS).

Pimonwan Kerdthep; Linna Tongyonk; Laddawan Rojanapantip

2009-01-01

66

Predicting arsenic concentrations in the porewaters of buried uranium mill tailings  

Microsoft Academic Search

The proposed JEB Tailings Management Facility (TMF) to be emplaced below the groundwater table in northern Saskatchewan, Canada, will contain uranium mill tailings from McClean Lake, Midwest and Cigar Lake ore bodies, which are high in arsenic (up to 10%) and nickel (up to 5%). A serious concern is the possibility that high arsenic and nickel concentrations may be released

Donald Langmuir; John Mahoney; Anjali MacDonald; John Rowson

1999-01-01

67

Impact of urine concentration adjustment method on associations between urine metals and estimated glomerular filtration rates (eGFR) in adolescents.  

PubMed

Positive associations between urine toxicant levels and measures of glomerular filtration rate (GFR) have been reported recently in a range of populations. The explanation for these associations, in a direction opposite that of traditional nephrotoxicity, is uncertain. Variation in associations by urine concentration adjustment approach has also been observed. Associations of urine cadmium, thallium and uranium in models of serum creatinine- and cystatin-C-based estimated GFR (eGFR) were examined using multiple linear regression in a cross-sectional study of adolescents residing near a lead smelter complex. Urine concentration adjustment approaches compared included urine creatinine, urine osmolality and no adjustment. Median age, blood lead and urine cadmium, thallium and uranium were 13.9 years, 4.0?g/dL, 0.22, 0.27 and 0.04g/g creatinine, respectively, in 512 adolescents. Urine cadmium and thallium were positively associated with serum creatinine-based eGFR only when urine creatinine was used to adjust for urine concentration (? coefficient=3.1mL/min/1.73m(2); 95% confidence interval=1.4, 4.8 per each doubling of urine cadmium). Weaker positive associations, also only with urine creatinine adjustment, were observed between these metals and serum cystatin-C-based eGFR and between urine uranium and serum creatinine-based eGFR. Additional research using non-creatinine-based methods of adjustment for urine concentration is necessary. PMID:24815335

Weaver, Virginia M; Vargas, Gonzalo García; Silbergeld, Ellen K; Rothenberg, Stephen J; Fadrowski, Jeffrey J; Rubio-Andrade, Marisela; Parsons, Patrick J; Steuerwald, Amy J; Navas-Acien, Ana; Guallar, Eliseo

2014-07-01

68

ARSENIC  

EPA Science Inventory

The report is an in-depth study that attempts to assemble, organize, and interpret present-day information on arsenic and its compounds, and the effects of these substances on man, animals, and plants. Emphasis is given to the effects of arsenic on man, conclusions are drawn from...

69

Comparison of Arsenic Concentrations in Carcass and Viscera of Swim-up Rainbow Trout Exposed to Dietary and Waterborne Arsenic  

EPA Science Inventory

Rainbow trout fry were exposed to arsenic in water only, diet only, or both diet and water in 28-d studies evaluating survival and growth. Diets consisted of Lumbriculus variegatus that were exposed to multiple concentrations of waterborne arsenate for 7d and then fed to test fi...

70

House dust and inorganic urinary arsenic in two Arizona mining towns.  

PubMed

Residents of copper mining and smelting towns may have increased risk of arsenic exposure from elevated arsenic contained in environmental media. To determine the relation of arsenic in house dust to inorganic urinary arsenic concentrations, a door-to-door survey was conducted in Hayden and Winkelman, Arizona. A total of 122 households (404 individuals) participated; 85 provided dust samples. Urine was collected at first morning void and analyzed for total and speciated arsenic. Speciation of arsenic was performed in samples with total arsenic above 10 micro g/l (N=106). The generalized estimating equation was used to determine the relation between urinary and house dust arsenic concentrations, allowing adjustment for the correlation of measurements obtained from the same home. Seafood consumption during the past 3 days and smoking contributed significantly to inorganic urinary arsenic, after adjusting for age and gender. Arsenic in house dust was not significantly associated with inorganic urinary arsenic measurements in this population. PMID:12743615

Hysong, Tracy A; Burgess, Jefferey L; Cebrián Garcia, Mariano E; O'Rourke, Mary Kay

2003-05-01

71

Arsenic risk assessment.  

PubMed Central

We review recent publications by Hopenhayn-Rich et al. and Smith et al. regarding two critical issues in arsenic risk assessment: the role of methylation in the dose-response relationship and the role of internal cancers. Hopenhayn-Rich et al. applied simple linear regression to data from several studies to determine whether the percentage of inorganic arsenic in urine increases with increasing dose. Although their results failed to show a correlation between percent inorganic arsenic and urinary arsenic concentration, their evaluation does not demonstrate the absence of a methylation threshold because of the relatively low level of arsenic in urine and the use of grab samples in evaluating methylating capacity. Using data from an epidemiological study in Taiwan, Smith et al. have indicated that arsenic could be an important risk factor not only for skin cancer (the basis of the current EPA cancer slope factor), but also for several internal cancers including lung, liver, bladder, and kidney. We note the following deficiencies in the analysis of Smith et al: 1) the likely underestimated exposure estimate due to lack of consideration on nonwater sources of arsenic and the underestimate of water consumption, 2) lack of consideration of detoxification in estimating potential risks from low-level exposures typical of the U.S. population, and 3) lack of consideration of key differences, particularly nutritional differences, between the Taiwanese and U.S. populations that could affect potential risks.

Carlson-Lynch, H; Beck, B D; Boardman, P D

1994-01-01

72

Stress-induced changes in corticosteroid metabolism. [plasma and urine concentrations  

NASA Technical Reports Server (NTRS)

Because plasma and urine corticosteroid concentrations are influenced by several factors in addition to adrenal cortex secretion, the effect of stress on all of these factors was determined in order to interpret the plasma and urine concentrations. Progress on the investigation is reported.

Tacker, M. M.

1975-01-01

73

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. 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

2014-01-01

74

Impaired arsenic metabolism in children during weaning  

SciTech Connect

Background: Methylation of inorganic arsenic (iAs) via one-carbon metabolism is a susceptibility factor for a range of arsenic-related health effects, but there is no data on the importance of arsenic metabolism for effects on child development. Aim: To elucidate the development of arsenic metabolism in early childhood. Methods: We measured iAs, methylarsonic acid (MA) and dimethylarsinic acid (DMA), the metabolites of iAs, in spot urine samples of 2400 children at 18 months of age. The children were born to women participating in a population-based longitudinal study of arsenic effects on pregnancy outcomes and child development, carried out in Matlab, a rural area in Bangladesh with a wide range of arsenic concentrations in drinking water. Arsenic metabolism was evaluated in relation to age, sex, anthropometry, socio-economic status and arsenic exposure. Results: Arsenic concentrations in child urine (median 34 {mu}g/L, range 2.4-940 {mu}g/L), adjusted to average specific gravity of 1.009 g/mL, were considerably higher than that measured at 3 months of age, but lower than that in maternal urine. Child urine contained on average 12% iAs, 9.4% MA and 78% DMA, which implies a marked change in metabolite pattern since infancy. In particular, there was a marked increase in urinary %MA, which has been associated with increased risk of health effects. Conclusion: The arsenic metabolite pattern in urine of children at 18 months of age in rural Bangladesh indicates a marked decrease in arsenic methylation efficiency during weaning.

Faengstroem, Britta [Institute of Environmental Medicine, Karolinska Institutet, Box 210, 171 77 Stockholm (Sweden); Hamadani, Jena [ICDDR-B: International Centre for Diarrhoeal Disease Research (Bangladesh); Nermell, Barbro; Grander, Margaretha; Palm, Brita [Institute of Environmental Medicine, Karolinska Institutet, Box 210, 171 77 Stockholm (Sweden); Vahter, Marie [Institute of Environmental Medicine, Karolinska Institutet, Box 210, 171 77 Stockholm (Sweden)], E-mail: marie.vahter@ki.se

2009-09-01

75

Relation between airborne arsenic trioxide and urinary excretion of inorganic arsenic and its methylated metabolites.  

PubMed Central

The relation between exposure to As2O3 fumes and dust, and the urinary excretion of inorganic arsenic metabolites (monomethylarsonic acid, dimethylarsinic acid, unchanged inorganic arsenic) has been studied in 18 workers from a sulphuric acid producing plant. The concentration of arsenic in the breathing zone of each worker was measured during five consecutive days and urine samples were obtained after one shift and before the next. The collection efficiency of the air sampling system exceeded 95%. The time weighted average exposure (TWA) concentrations of As2O3 ranged from 6 to 502 micrograms As/m3 and were log normally distributed. Although exposure probably occurred by ingestion as well as inhalation, statistically significant correlations (log scales) were found between airborne TWA of As2O3 and the inorganic arsenic metabolites in urine collected immediately after the shift, or just before the next shift. For a TWA of 50 micrograms As/m3, the mean concentration of the sum of the three inorganic arsenic metabolites in a postshift urine sample amounted to about 55 micrograms arsenic/g creatinine (95% confidence interval (95% CI) 47-62). Higher estimates of urinary arsenic reported by other authors are probably due either to the influence of dietary organoarsenicals when total arsenic is measured in urine or to a low retention efficiency of the air sampling system for As2O3 in the vapour phase.

Offergelt, J A; Roels, H; Buchet, J P; Boeckx, M; Lauwerys, R

1992-01-01

76

High arsenic intake raises kidney copper and lowers plasma copper concentrations in rats.  

PubMed

The effect of high arsenic intake on copper metabolism was investigated. Male rats aged 6 wk had free access to purified diets containing either 0 or 100 mg As/kg diet and demineralized water for a period of 2 wk. Arsenic was added to the diet in the form of NaAsO2. The high-arsenic diet decreased feed and water intake and body weight gain, but significantly increased liver weight. Kidney weight was not affected. Arsenic feeding drastically elevated kidney copper concentration, but significantly reduced copper concentration in plasma. Both true absorption and biliary excretion of copper were decreased significantly in rats fed the high-arsenic diet. True copper absorption was lowered essentially through the lower copper intake in the rats fed arsenic. It is speculated that arsenic feeding primarily leads to copper accumulation in the kidney, followed by a decrease in feed intake and thus in true, absolute copper absorption, a decrease in plasma copper concentration, and a decrease in biliary copper excretion. PMID:11508332

Yu, S; Beynen, A C

2001-07-01

77

Correlation Between Arsenic Concentration in Fish and Human Scalp Hair of People Living in Arsenic-Contaminated and Noncontaminated Areas of Pakistan  

Microsoft Academic Search

The effects of arsenic (As) toxicity due to frequent consumption of arsenic-contaminated fish was estimated by the analysis\\u000a of scalp hair of adult males, living near arsenic-contaminated area of Pakistan. For comparison purposes, scalp hair samples\\u000a were also collected from the inhabitants of Hyderabad city consuming fish species with low levels of As, collected from Indus\\u000a River. Concentration of As

Abdul Qadir Shah; Tasneem Gul Kazi; Jameel Ahmad Baig; Hassan Imran Afridi

78

The Silicon Concentration in Cat Urine and Its Relationship with Other Elements  

PubMed Central

ABSTRACT To understand the effects of silicon (Si) in the urine with respect to the formation of urinary stones, the distribution of Si in urine was observed. Urine samples from cats with urolithiasis (n=10) and healthy cats (n=15) were used. The concentration of Si in the cats with urolithiasis was significantly higher (P<0.001). A significant correlation (P<0.05) was observed between the concentration of Si and those of other elements, such as calcium, magnesium, phosphorus, potassium and iron, only in the urine of the healthy cats. The distribution of elements in the urine differed between the cats with urolithiasis and the healthy cats. The Si concentration and its relationship with other elements were suggested to be useful biomarkers for urolithiasis in cats.

TAKAHASHI, Fumihito; MOCHIZUKI, Mariko; YOGO, Takuya; ISHIOKA, Katsumi; YUMOTO, Norio; SAKO, Toshinori; UEDA, Fukiko; TAGAWA, Masahiro; TAZAKI, Hiroyuki

2013-01-01

79

Effect of arsenic concentration on microbial iron reduction and arsenic speciation in an iron-rich freshwater sediment  

NASA Astrophysics Data System (ADS)

Depth profiles in the sediment porewaters of the Chattahoochee River (Georgia, USA) show that iron oxides scavenge arsenate in the water column and settle to the sediment-water interface (SWI) where they are reduced by iron-reducing bacteria. During their reduction, these particles seem to release arsenic to the porewaters in the form of arsenate only. Sediment slurry incubations were conducted to determine the effect of low concentrations of arsenic (?10 ?M) on biogeochemical processes in these sediments. Experiments confirm that any arsenate (As(V)) added to these sediments is immediately adsorbed in oxic conditions and released in anoxic conditions during the microbial reduction of authigenic iron oxides. Incubations in the presence of ?1 ?M As(V) reveal that arsenate is released but not concomitantly reduced during this process. Simultaneously, microbial iron reduction is enhanced significantly, spurring the simultaneous release of arsenate into porewaters and secondary formation of crystalline iron oxides. Above 1 ?M As(V), however, the microbial reductive dissolution of iron oxides appears inhibited by arsenate, and arsenite is produced in excess in the porewaters. These incubations show that even low inputs of arsenic to riverine sediments may affect microbial processes, the stability of iron oxides and, indirectly, the cycling of arsenic. Possible mechanisms for such effects on iron reduction are proposed.

Chow, Stephanie S.; Taillefert, Martial

2009-10-01

80

Spatial Variability of Arsenic Concentrations in two Villages in Araihazar Upazila, Narayanganj District of Bangladesh  

NASA Astrophysics Data System (ADS)

In the Ganges-Brahmaputra Delta, concentrations of arsenic in tube wells have been known to vary spatially on both the basin (tens of km) and the local (tens of meter) scale. Based on arsenic concentration measured in 5000 contiguous tube wells from Araihazar Upazila, 20 km east of Dhaka, we began to investigate the geological, hydrological and geochemical controls on the arsenic spatial heterogeneity in two villages on spatial scales of order 100 m in January, 2001. In Dari Satyabhadi village (23.785° N, 90.603° E), arsenic concentrations in 157 wells range from <5 ug/L to 800 ug/L (123 +/- 154 ug/L), with 51% of wells containing >50 ug/L. Arsenic concentrations in 124 wells from Baylakandi village (23.780° N, 90.640° E) range from 10 ug/L to 520 ug/L (266 +/- 95 ug/L), with 98% of wells above 50 ug/L. Sediment coring in both villages to 92 m depth recovered a fine-grained clay zone separating an upper, perhaps less confined aquifer and a lower, confined aquifer. In Dari Satyabhadi village, The clay is located between 13 m and 30 m, with a thin silty sand layer at 20.1-20.7 m and a peat layer at 20.7-21.4 m. Below the clay, all existing tube wells, as well as monitoring wells, are found to have arsenic concentrations <50 ug/L. In Baylakandi village, a clay layer was found at greater depth between 30 and 50 m, with a silty sand layer between 36 and 43 m. None of the existing tube wells are deeper than the clay in Baylakandi, but monitoring wells installed at 53 m and 92 m yield water containing <50 ug/L arsenic. Results from both villages suggest that a lower aquifer isolated by a clay layer from shallow, high-arsenic aquifer contains little arsenic. In contrast, there is, however, considerable spatial variability in arsenic concentrations in both villages within the upper aquifer. In Dari Satyabhadi, arsenic concentrations in 120 shallow wells (< 30 m) from the upper aquifer ranges from <5 ug/L to 800 ug/L (158 +/- 160 ug/L), with 66% of wells above 50 ug/L. The source of this variability appears to be linked to the distribution of fine and coarse sediment near the surface, which were documented using shallow geophysical techniques.

Dhar, R.; Zheng, Y.; Zheng, Y.; Stute, M.; Stute, M.; van Geen, A.; Gavrieli, I.; Gavrieli, I.; Versteeg, R.; Versteeg, R.; Steckler, M.; Goodbred, S.; Horneman, A.; Simpson, H. J.; Ahmed, K. M.

2001-05-01

81

Uranium and Thorium in Urine of United States Residents: Reference Range Concentrations  

Microsoft Academic Search

We measured uranium and thorium in urine of 500 U. S. residents to establish reference range concentrations using a magnetic-sector inductively coupled argon plasma mass spectrometer (ICP-MS). We found uranium at detectable concentrations in 96.6% of the urine specimens and thorium in 39.6% of the specimens. The 95th percentile concenetration for uranium was 34.5 ng\\/L (parts per trillion); concentrations ranged

Bill G. Ting; Daniel C. Paschal; Jeffery M. Jarrett; James L. Pirkle; Richard J. Jackson; Eric J. Sampson; Dayton T. Miller; Samuel P. Caudill

1999-01-01

82

Concentrations of arsenic, antimony, and boron in steam and steam condensate at The Geysers, California  

USGS Publications Warehouse

Studies at The Geysers Geothermal Field, California indicate that under some circumstances elements that are transported in the vapor phase can become enriched in the liquid phase. Waters from two condensate traps (steam traps) on steam lines at The Geysers are enriched with arsenic, antimony, and boron compared to the concentrations of these elements in coexisting steam. Concentrations of boron in condensate-trap waters were as high as 160 mg/L, arsenic as high as 35 mg/L, and antimony as high as 200 ??g/L. Enrichment of arsenic, antimony, and boron is at least partially controlled by the partitioning of these elements into the liquid phase, according to their vapor-liquid distribution coefficients, after they are transported in steam. Several of the elements that are most soluble in steam, including arsenic and antimony, are part of the trace-element suite that characterizes precious-metal epithermal ore deposits. ?? 1987.

Smith, C. L.; Ficklin, W. H.; Thompson, J. M.

1987-01-01

83

Rice Consumption and Urinary Arsenic Concentrations in U.S. Children  

PubMed Central

Background: In adult populations, emerging evidence indicates that humans are exposed to arsenic by ingestion of contaminated foods such as rice, grains, and juice; yet little is known about arsenic exposure among children. Objectives: Our goal was to determine whether rice consumption contributes to arsenic exposure in U.S. children. Methods: We used data from the nationally representative National Health and Nutrition Examination Survey (NHANES) to examine the relationship between rice consumption (measured in 0.25 cups of cooked rice per day) over a 24-hr period and subsequent urinary arsenic concentration among the 2,323 children (6–17 years of age) who participated in NHANES from 2003 to 2008. We examined total urinary arsenic (excluding arsenobetaine and arsenocholine) and dimethylarsinic acid (DMA) concentrations overall and by age group: 6–11 years and 12–17 years. Results: The median [interquartile range (IQR)] total urinary arsenic concentration among children who reported consuming rice was 8.9 ?g/L (IQR: 5.3–15.6) compared with 5.5 ?g/L (IQR: 3.1–8.4) among those who did not consume rice. After adjusting for potentially confounding factors, and restricting the study to participants who did not consume seafood in the preceding 24 hr, total urinary arsenic concentration increased 14.2% (95% confidence interval: 11.3, 17.1%) with each 0.25 cup increase in cooked rice consumption. Conclusions: Our study suggests that rice consumption is a potential source of arsenic exposure in U.S. children.

Davis, Matthew A.; Mackenzie, Todd A.; Cottingham, Kathryn L.; Gilbert-Diamond, Diane; Punshon, Tracy

2012-01-01

84

Urine concentrations of oral salbutamol in samples collected after intense exercise in endurance athletes.  

PubMed

Our objective was to investigate urine concentrations of 8?mg oral salbutamol in samples collected after intense exercise in endurance athletes. Nine male endurance athletes with a VO2max of 70.2?±?5.9?mL/min/kg (mean?±?SD) took part in the study. Two hours after administration of 8?mg oral salbutamol, subjects performed submaximal exercise for 15?min followed by two, 2-min exercise bouts at an intensity corresponding to 110% of VO2max and a bout to exhaustion at same intensity. Urine samples were collected 4, 8, and 12?h following administration of salbutamol. Samples were analyzed by the Norwegian World Anti-doping Agency (WADA) laboratory. Adjustment of urine concentrations of salbutamol to a urine specific gravity (USG) of 1.020?g/mL was compared with no adjustment according to WADA's technical documents. We observed greater (P?=?0.01) urine concentrations of salbutamol 4?h after administration when samples were adjusted to a USG of 1.020?g/mL compared with no adjustment (3089?±?911 vs. 1918?±?1081?ng/mL). With the current urine decision limit of 1200?ng/mL for salbutamol on WADA's 2013 list of prohibited substances, fewer false negative urine samples were observed when adjusted to a USG of 1.020?g/mL compared with no adjustment. In conclusion, adjustment of urine samples to a USG of 1.020?g/mL decreases risk of false negative doping tests after administration of oral salbutamol. Adjusting urine samples for USG might be useful when evaluating urine concentrations of salbutamol in doping cases. Copyright © 2013 John Wiley & Sons, Ltd. PMID:24166762

Hostrup, Morten; Kalsen, Anders; Auchenberg, Michael; Rzeppa, Sebastian; Hemmersbach, Peter; Bangsbo, Jens; Backer, Vibeke

2014-06-01

85

Measurement of vanadium, nickel, and arsenic in seawater and urine reference materials by inductively coupled plasma mass spectrometry with cryogenic desolvation  

Microsoft Academic Search

Addition of a small dose (2%) of H[sub 2] to the aerosol gas flow enhanced analyte signals by a factor of 2-3, which compensated for the loss of analyte signal that accompanied earlier efforts at cryogenic desolvation with inductively coupled plasma mass spectrometry (ICP-MS). Vanadium, nickel, and arsenic at microgram per liter levels in urine, river, and seawater reference materials

Luis C. Alves; Lloyd A. Allen; R. S. Houk

1993-01-01

86

Silver nanoparticles promote osteogenic differentiation of human urine-derived stem cells at noncytotoxic concentrations  

PubMed Central

In tissue engineering, urine-derived stem cells are ideal seed cells and silver nanoparticles (AgNPs) are perfect antimicrobial agents. Due to a distinct lack of information on the effects of AgNPs on urine-derived stem cells, a study was conducted to evaluate the effects of silver ions and AgNPs upon the cytotoxicity and osteogenic differentiation of urine-derived stem cells. Initially, AgNPs or AgNO3 were exposed to urine-derived stem cells for 24 hours. Cytotoxicity was measured using the Cell Counting kit-8 (CCK-8) test. The effects of AgNPs or AgNO3 at the maximum safety concentration determined by the CCK-8 test on osteogenic differentiation of urine-derived stem cells were assessed by alkaline phosphatase activity, Alizarin Red S staining, and the quantitative reverse transcription polymerase chain reaction. Lastly, the effects of AgNPs or AgNO3 on “urine-derived stem cell actin cytoskeleton organization” and RhoA activity were assessed by rhodamine-phalloidin staining and Western blotting. Concentration-dependent toxicity was observed starting at an AgNO3 concentration of 2 ?g/mL and at an AgNP concentration of 4 ?g/mL. At these concentrations, AgNPs were observed to promote osteogenic differentiation of urine-derived stem cells, induce actin polymerization and increase cytoskeletal tension, and activate RhoA; AgNO3 had no such effects. In conclusion, AgNPs can promote osteogenic differentiation of urine-derived stem cells at a suitable concentration, independently of silver ions, and are suitable for incorporation into tissue-engineered scaffolds that utilize urine-derived stem cells as seed cells.

Qin, Hui; Zhu, Chen; An, Zhiquan; Jiang, Yao; Zhao, Yaochao; Wang, Jiaxin; Liu, Xin; Hui, Bing; Zhang, Xianlong; Wang, Yang

2014-01-01

87

Concentration-dependent cellular responses of arsenic in keratinocytes  

Microsoft Academic Search

Arsenic (As) is considered as a human carcinogen or tumor-promoting agent. Epidemiological evidences indicated that cancer incidences of residents in arseniasis areas were significantly higher in multiple organs, including urinary bladder, lungs, and especially the skin, than those living in non-arseniasis areas. In the context of skin cancers, keratinocytes are believed to be the main target cells in As carcinogenesis.

Wei-Ting Liao; Cheng-Che Eric Lan; Chih-Hung Lee; Hsin-Su Yu

2011-01-01

88

Urinary Arsenic Metabolites of Subjects Exposed to Elevated Arsenic Present in Coal in Shaanxi Province, China  

PubMed Central

In contrast to arsenic (As) poisoning caused by naturally occurring inorganic arsenic-contaminated water consumption, coal arsenic poisoning (CAP) induced by elevated arsenic exposure from coal combustion has rarely been reported. In this study, the concentrations and distributions of urinary arsenic metabolites in 57 volunteers (36 subjects with skin lesions and 21 subjects without skin lesions), who had been exposed to elevated levels of arsenic present in coal in Changshapu village in the south of Shaanxi Province (China), were reported. The urinary arsenic species, including inorganic arsenic (iAs) [arsenite (iAsIII) and arsenate (iAsV)], monomethylarsonic acid (MMAV) and dimethylarsinic acid (DMAV), were determined by high-performance liquid chromatography (HPLC) combined with inductively coupled plasma mass spectroscopy (ICP-MS). The relative distributions of arsenic species, the primary methylation index (PMI = MMAV/iAs) and the secondary methylation index (SMI = DMAV/MMAV) were calculated to assess the metabolism of arsenic. Subjects with skin lesions had a higher concentration of urinary arsenic and a lower arsenic methylation capability than subjects without skin lesions. Women had a significantly higher methylation capability of arsenic than men, as defined by a higher percent DMAV and SMI in urine among women, which was the one possible interpretation of women with a higher concentration of urinary arsenic but lower susceptibility to skin lesions. The findings suggested that not only the dose of arsenic exposure but also the arsenic methylation capability have an impact on the individual susceptibility to skin lesions induced by coal arsenic exposure.

Gao, Jianwei; Yu, Jiangping; Yang, Linsheng

2011-01-01

89

Reduction of arsenic content in a complex galena concentrate by Acidithiobacillus ferrooxidans  

PubMed Central

Background Bioleaching is a process that has been used in the past in mineral pretreatment of refractory sulfides, mainly in the gold, copper and uranium benefit. This technology has been proved to be cheaper, more efficient and environmentally friendly than roasting and high pressure moisture heating processes. So far the most studied microorganism in bioleaching is Acidithiobacillus ferrooxidans. There are a few studies about the benefit of metals of low value through bioleaching. From all of these, there are almost no studies dealing with complex minerals containing arsenopyrite (FeAsS). Reduction and/or elimination of arsenic in these ores increase their value and allows the exploitation of a vast variety of minerals that today are being underexploited. Results Arsenopyrite was totally oxidized. The sum of arsenic remaining in solution and removed by sampling represents from 22 to 33% in weight (yield) of the original content in the mineral. The rest of the biooxidized arsenic form amorphous compounds that precipitate. Galena (PbS) was totally oxidized too, anglesite (PbSO4) formed is virtually insoluble and remains in the solids. The influence of seven factors in a batch process was studied. The maximum rate of arsenic dissolution in the concentrate was found using the following levels of factors: small surface area of particle exposure, low pulp density, injecting air and adding 9 K medium to the system. It was also found that ferric chloride and carbon dioxide decreased the arsenic dissolution rate. Bioleaching kinetic data of arsenic solubilization were used to estimate the dilution rate for a continuous culture. Calculated dilution rates were relatively small (0.088–0.103 day-1). Conclusion Proper conditions of solubilization of arsenic during bioleaching are key features to improve the percentage (22 to 33% in weight) of arsenic removal. Further studies are needed to determine other factors that influence specifically the solubilization of arsenic in the bioleaching system such as: pH, dissolved oxygen concentration, redox potentials, nature of concentrate and temperature among others. At. ferrooxidans was able to completely oxidize the minerals present during the arsenic bioleaching. Other elements present originally in the concentrate such as Zn, Sb, and Cu were also solubilized. The process of bioleaching is expected to be influenced by mechanisms that still need to be established due to the diversity of the minerals involved and by the presence of traces of metals in the concentrate. The increase in pulp density generates a decrease in the dissolved arsenic concentration. This decrease is greater in runs where air was not injected to the system. The maximum rate of arsenic dissolution in the concentrate was found using; small surface area of particle exposure, low pulp density, injecting air and adding 9 K medium to the system. The effect of addition of ferric chloride during the arsenic bioleaching resulted in a decrease of the solubilized arsenic in the system. The presence of CO2 is associated to the decrease in arsenic dissolution.

Makita, Mario; Esperon, Margarita; Pereyra, Benito; Lopez, Alejandro; Orrantia, Erasmo

2004-01-01

90

Environmental arsenic exposure and serum matrix metalloproteinase-9  

PubMed Central

The objective of this study was to evaluate the relationship between environmental arsenic exposure and serum matrix metalloproteinase (MMP)-9, a biomarker associated with cardiovascular disease and cancer. In a cross-sectional study of residents of Arizona, USA (n=215) and Sonora, Mexico (n=163), drinking water was assayed for total arsenic, and daily drinking water arsenic intake estimated. Urine was speciated for arsenic and concentrations were adjusted for specific gravity. Serum was analyzed for MMP-9 using ELISA. Mixed model linear regression was used to assess the relation among drinking water arsenic concentration, drinking water arsenic intake, urinary arsenic sum of species (the sum of arsenite, arsenate, monomethylarsonic acid and dimethylarsinic acid), and MMP-9, controlling for autocorrelation within households. Drinking water arsenic concentration and intake were positively associated with MMP-9, both in crude analysis and after adjustment for gender, country/ethnicity, age, body mass index, current smoking and diabetes. Urinary arsenic sum of species was positively associated with MMP-9 in multivariable analysis only. Using Akaike’s Information Criterion, arsenic concentration in drinking water provided a better fitting model of MMP-9, than either urinary arsenic or drinking water arsenic intake. In conclusion, arsenic exposure was positively associated with MMP-9 using all three exposure metrics evaluated.

Burgess, Jefferey L.; Kurzius-Spencer, Margaret; O'Rourke, Mary Kay; Littau, Sally R.; Roberge, Jason; Meza-Montenegro, Maria Mercedes; Gutierrez-Millan, Luis Enrique; Harris, Robin B.

2014-01-01

91

Experimental studies on arsenic absorption routes in rats  

PubMed Central

Pentavalent inorganic arsenic was introduced by intravenous, intratracheal, gastrointestinal, and skin application in doses 0.1 to 4.0 mg/kg in rats. Isotopic technics were applied by use of As74. It was found that the dynamics of arsenic distribution in the body as well as the kinetics of its elimination in urine and feces varies very substantially, depending on the mode of administration. Intravenous administration of As causes immediate appearance of arsenic in most tissues and a slow decrease of its concentrations in time. Similar situations could be observed with intratracheal dosing, because arsenic is very rapidly absorbed from the site of administration. Concentration in tissues increases more slowly after gastrointestinal resorption. Skin application causes first the accumulation of arsenic in the skin and next continuous, slow transport from the skin into the blood stream. The rate of skin resorption was 1.14–33.1 ?g/cm2-hr for 0.01–0.2M concentrations. The red blood cell level of arsenic is very substantial and does not change with time, which indicates the accumulation of arsenic in this tissue. The elimination of arsenic occurred chiefly in urine and feces, but the urine/feces ratio changed very substantially, depending on the route of administration. The kinetics of arsenic elimination in urine was multiphasic, being three-phase in case of intravenous and intratracheal administration and two-phase after gavage and skin resorption. After intravenous administration of As, the half-times of elimination were 2.5, 10, and 690 hr, respectively. Administration of selenium salts during the slow phase increased the rate of arsenic elimination. The straight-line relations found between the absorbed dose of arsenic and its blood or urine concentrations could serve as baselines for exposure tests for humans.

Dutkiewicz, Tadeusz

1977-01-01

92

Reconnaissance of Arsenic Concentrations in Ground Water From Bedrock and Unconsolidated Aquifers in Eight Northern-Tier Counties of Pennsylvania  

USGS Publications Warehouse

Samples of ground water for analysis of total-arsenic concentrations were collected in eight counties--Potter, Tioga, Bradford, Susquehanna, Wayne, Pike, Sullivan, and Wyoming--and from eight bedrock formations (bedrock aquifers) and overlying glacial aquifers in the north-central and northeastern parts of Pennsylvania in July 2005 and from March through June 2006. The samples were collected from a total of 143 domestic wells, 2 stock wells, 4 non-community wells, 2 community water-system wells, and 3 domestic springs by well or spring owners using sampling kits provided by the U.S. Geological Survey (USGS). An additional 15 domestic wells were sampled by the USGS for analysis of total arsenic. These 15 samples were collected using the same methods and sampling kits provided to the homeowners. Samples were analyzed for total arsenic by the Pennsylvania Department of Environmental Protection Laboratory using a minimum reporting level of 4.0 ?g/L (micrograms per liter). Arsenic was detected in water from 18 domestic wells in four counties--Bradford (3 wells), Sullivan (1 well), Tioga (13 wells), and Wayne (1 well). The median concentration of total arsenic was less than 4.0 ?g/L, and the maximum concentration was 188 ?g/L. Water from 10 wells had concentrations of total arsenic greater than the U.S. Environmental Protection Agency Maximum Contaminant Level of 10 ?g/L. Detectable concentrations of total arsenic were measured in water from wells that ranged in depth from 29 to 400 feet, and that were completed in three aquifers--Lock Haven Formation, Catskill Formation, and unconsolidated glacial sediments; no springs had detectable concentrations of total arsenic. Water samples representing the Lock Haven Formation were collected from 60 wells; water from 12 of these wells had detectable concentrations of total arsenic. Water samples representing the Catskill Formation were collected from 57 wells; water from 4 wells had detectable concentrations of total arsenic. Water samples representing the unconsolidated glacial sediments were collected from 17 wells; 2 wells had water with detectable concentrations of total arsenic. Contingency tables tested for significant differences in total arsenic between aquifers, topographic settings, and well depths. Concentrations of total arsenic were significantly greater (95-percent confidence level) in the Lock Haven Formation than in the other bedrock units. Concentrations of total arsenic also varied significantly by topographic setting. Wells completed in the Lock Haven Formation and located in valleys had significantly greater concentrations of total arsenic than similar wells located on hilltops or slopes. Concentrations of total arsenic did not vary significantly by topographic setting in the Catskill Formation. Concentrations of total arsenic did not vary significantly by well depth for any aquifer. Iron staining, hydrogen-sulfide odor, or both were common complaints of well owners. Iron staining was a complaint of 44 well owners. Hydrogen-sulfide odor was a complaint of 35 well owners. Fourteen well owners complained of both iron staining and hydrogen sulfide. No correlation to the presence of arsenic in the wells sampled was found with iron staining, hydrogen-sulfide odor, or both. Water from 8 of the 10 wells that contained concentrations of total arsenic greater than 10 ?g/L were sampled by USGS personnel for the determination of concentrations of dissolved arsenic (minimum reporting level 0.3 ?g/L) and arsenic species {arsenite [As (III)], arsenate [As (V)], monomethylarsonate (MMA), and dimethylarsinate (DMA)} at the USGS National Water Quality Laboratory. Analytical results from these samples showed a median concentration of 38.7 ?g/L dissolved arsenic in water and a maximum of 178 ?g/L. As (III) was the most common arsenic species present in the water for seven of the eight wells and was found in water characteristic of reducing environments [pH 8.2

Low, Dennis J.; Galeone, Daniel G.

2007-01-01

93

Effect of Environmental Exposure of Arsenic on Cattle and Poultry in Nadia District, West Bengal, India  

PubMed Central

A study was undertaken to evaluate an alternative source of arsenicosis in human food chain through livestock. Thirty milch cattle and 20 poultry birds along with their eggs were selected randomly from two endemic villages of Nadia district and one nonendemic villages of Hooghly district in West Bengal, India. Milk, feces, urine, and hair samples of cattle and feed materials, such as water and straw, were collected to analyze arsenic status. Arsenic concentration in egg yolk and albumen from poultry eggs and different poultry organs after culling was estimated. Distribution of arsenic in animal body indicates that major portion of arsenic was eliminated through feces, urine, and milk. Poultry egg yolk, albumen, and poultry products retain arsenic in all organs. Cows and poultry birds reared in endemic zone retain significantly higher concentration of arsenic. Consumption of egg, agricultural produces grown in contaminated soil, and milk might have produced arsenicosis and may be considered as alternative source of arsenic contamination.

Datta, Bakul Kumar; Bhar, Moloy Kumar; Patra, Pabitra Hriday; Majumdar, Debasish; Dey, Radha Raman; Sarkar, Samar; Mandal, Tapan Kumar; Chakraborty, Animesh Kumar

2012-01-01

94

Treatment of concentrated arsenic(V) solutions by micellar enhanced ultrafiltration with high molecular weight cut-off membrane  

Microsoft Academic Search

In this work arsenic removal by micellar enhanced ultrafiltration (MEUF) was investigated using cetylpyridinium chloride (CPC) and a cross-flow polyethersulphone (PES) membrane apparatus. The effects of some operating factors on permeate flux, arsenic and CPC rejections were investigated and, in particular, transmembrane pressure, pH, CPC concentration, As concentration and ionic strength. The novel aim of this work is evaluating the

F. Beolchini; F. Pagnanelli; I. De Michelis; F. Vegliň

2007-01-01

95

Creatinine, Diet, Micronutrients, and Arsenic Methylation in West Bengal, India  

PubMed Central

Background: Ingested inorganic arsenic (InAs) is methylated to monomethylated (MMA) and dimethylated metabolites (DMA). Methylation may have an important role in arsenic toxicity, because the monomethylated trivalent metabolite [MMA(III)] is highly toxic. Objectives: We assessed the relationship of creatinine and nutrition—using dietary intake and blood concentrations of micronutrients—with arsenic metabolism, as reflected in the proportions of InAS, MMA, and DMA in urine, in the first study that incorporated both dietary and micronutrient data. Methods: We studied methylation patterns and nutritional factors in 405 persons who were selected from a cross-sectional survey of 7,638 people in an arsenic-exposed population in West Bengal, India. We assessed associations of urine creatinine and nutritional factors (19 dietary intake variables and 16 blood micronutrients) with arsenic metabolites in urine. Results: Urinary creatinine had the strongest relationship with overall arsenic methylation to DMA. Those with the highest urinary creatinine concentrations had 7.2% more arsenic as DMA compared with those with low creatinine (p < 0.001). Animal fat intake had the strongest relationship with MMA% (highest tertile animal fat intake had 2.3% more arsenic as MMA, p < 0.001). Low serum selenium and low folate were also associated with increased MMA%. Conclusions: Urine creatinine concentration was the strongest biological marker of arsenic methylation efficiency, and therefore should not be used to adjust for urine concentration in arsenic studies. The new finding that animal fat intake has a positive relationship with MMA% warrants further assessment in other studies. Increased MMA% was also associated, to a lesser extent, with low serum selenium and folate.

Basu, Arin; Mitra, Soma; Chung, Joyce; Guha Mazumder, D.N.; Ghosh, Nilima; Kalman, David; von Ehrenstein, Ondine S.; Steinmaus, Craig; Liaw, Jane

2011-01-01

96

Effect of Hemodialysis and Renal Failure on Serum and Urine Concentrations of Cephapirin Sodium  

PubMed Central

Six patients undergoing chronic hemodialysis and 10 patients with chronic renal insufficiency hospitalized for nondialytic therapy received 1.0 g of cephapirin sodium by the intravenous route. The concentrations of cephapirin in arterial and venous plasma, dialysate, venous blood, and urine were measured during the ensuing 6 hr. The serum half-life of cephapirin was 105 to 108 min for the dialyzed patients and 95.9 min for the nondialyzed patients. Dialysis removed 22.8% of the administered dose. Nondialyzed patients excreted 19.5% of the administered dose in the urine. The concentration of cephapirin in the urine of all nondialyzed patients exceeded 50 ?g/ml. The recovery of cephapirin in the urine collected for 6 hr after injection was from 34 to 770 mg (mean 195 mg). To maintain a concentration of cephapirin in the blood and urine which exceeds the minimal inhibitory concentration for most gram-positive and gram-negative microorganisms, nondialyzed patients should receive 15 to 18 mg of cephapirin per kg every 12 hr. Dialyzed patients should receive the same dose just prior to dialysis and every 12 hr thereafter.

McCloskey, R. V.; Terry, E. E.; McCracken, A. W.; Sweeney, M. J.; Forland, M. F.

1972-01-01

97

Total and inorganic arsenic concentrations in different species of economically important algae harvested from coastal zones of Chile.  

PubMed

Chile is one of the major producers of phytocolloids extracted from seaweed. Multicellular algae are considered to be primary accumulators of arsenic. We analyzed 14 species of algae belonging to the groups Rhodophyceae (10), Phaeophyceae (3) and Chlorophyceae (1) from different coastal zones of Chile in 2003-2004. Dry ashing mineralization (for total As) and acid digestion (for inorganic As) together with quantification by flow injection hydride generation atomic absorption spectrometry (FI-HG-AAS) were employed. In general, total arsenic concentrations varied between 3.0 and 68 mg kg(-1), whereas inorganic arsenic concentrations ranged between 0.15 and 1.06 mg kg(-1). The algal species Durvillaea antarctica and Porphyra columbina, used for direct human consumption, did not have inorganic arsenic levels that represent a health risk to consumers. Among species used for phytocolloids production, such as Macrocystis piryfera, Gracilaria chilensis and Gigartina skottsbergii, observed levels of inorganic arsenic were greater than 1 mg kg(-1), the limit value established by the regulations of some countries. Among the 14 species of algae tested, inorganic arsenic levels were between 0.8% and 13% of the total arsenic concentrations; that is, arsenic present in these algae was found primarily as organic arsenic. PMID:22138359

Díaz, Oscar; Tapia, Yasna; Muńoz, Ociel; Montoro, Rosa; Velez, Dinoraz; Almela, Concepción

2012-03-01

98

Chromium, Copper, and Arsenic Concentrations in Soil Underneath CCA-Treated Wood Structures  

Microsoft Academic Search

Soils below nine structures (decks and foot bridges) in Florida were examined to evaluate potential impacts from chromated copper arsenate (CCA), a common wood preservative. Eight of the nine structures were confirmed to have been treated with CCA. Soils collected were evaluated for arsenic, chromium, and copper concentrations as well as pH, volatile solids content and particle size distribution. Two

Timothy Townsend; Helena Solo-Gabriele; Thabet Tolaymat; Kristin Stook; Naila Hosein

2003-01-01

99

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

100

HIGH ARSENIC CONCENTRATIONS AND ENRICHED SULFUR AND OXYGEN ISOTOPES IN A FRACTURED-BEDROCK GROUND-WATER SYSTEM  

EPA Science Inventory

Elevated arsenic concentrations are coincident with enriched sulfur and oxygen isotopes of sulfate in bedrock ground water within Kelly's Cove watershed, Northport, Maine, USA. Interpretation of the data is complicated by the lack of correlations between sulfate concentrations an...

101

Multiple Sclerosis Incidence Associated with the Soil Lead and Arsenic Concentrations in Taiwan  

PubMed Central

Background Few studies in the world have assessed the incidence of multiple sclerosis (MS) with soil heavy metal concentrations. We explored the association of soil heavy metal factors and the MS incidence in Taiwan. Methods There were 1240 new MS cases from the National Health Insurance Research Database and were verified with serious disabling disease certificates, 1997–2008. Soil heavy metal factors records included arsenic, mercury, cadmium, chromium, copper, nickel, lead and zinc in Taiwan from 1986 to 2002. Spatial regression was used to reveal the association of soil heavy metals and age- and gender-standardized incidence ratios for townships by controlling sunlight exposure hours, smoking prevalence and spatial autocorrelation. Results The lead (Pb) concentration in the soil positively correlated with the township incidence; on the other hand, the arsenic (As) concentration in soil negatively correlated with the township incidence and when found together controlled each other. The positive correlation of lead (Pb) predominated in males, whereas the negative correlation of arsenic (As) in soil predominated in females. Conclusions We conclude that exposure to lead (Pb) in soil positive associated with incidence of MS in Taiwan, especially in males. Exposure to arsenic (As) in soil negative associated with MS in Taiwan, especially in females.

2013-01-01

102

Bioleaching of arsenic-rich gold concentrates by bacterial flora before and after mutation.  

PubMed

In order to improve the bioleaching efficiency of arsenic-rich gold concentrates, a mixed bacterial flora had been developed, and the mutation breeding method was adopted to conduct the research. The original mixed bacterial flora had been enrichedin acid mine drainage of Dexing copper mine, Jiangxi Province, China. It was induced by UV (ultraviolet), ultrasonic, and microwave, and their combination mutation. The most efficient bacterial flora after mutation was collected for further bioleaching of arsenic-rich gold concentrates. Results indicated that the bacterial flora after mutation by UV 60?s combined with ultrasonic 10?min had the best oxidation rate of ferrous, the biggest density of cells, and the most activity of total protein. During bioleaching of arsenic-rich gold concentrates, the density of the mutant bacterial cells reached to 1.13 × 10? cells/mL at 15 days, more than 10 times compared with that of the original culture. The extraction of iron reached to 95.7% after 15 days, increased by 9.9% compared with that of the original culture. The extraction of arsenic reached to 92.6% after 12 days, which was increased by 46.1%. These results suggested that optimum combined mutation could improve leaching ability of the bacterial flora more significantly. PMID:24381948

Xie, Xuehui; Yuan, Xuewu; Liu, Na; Chen, Xiaoguang; Abdelgadir, Awad; Liu, Jianshe

2013-01-01

103

Bioleaching of Arsenic-Rich Gold Concentrates by Bacterial Flora before and after Mutation  

PubMed Central

In order to improve the bioleaching efficiency of arsenic-rich gold concentrates, a mixed bacterial flora had been developed, and the mutation breeding method was adopted to conduct the research. The original mixed bacterial flora had been enrichedin acid mine drainage of Dexing copper mine, Jiangxi Province, China. It was induced by UV (ultraviolet), ultrasonic, and microwave, and their combination mutation. The most efficient bacterial flora after mutation was collected for further bioleaching of arsenic-rich gold concentrates. Results indicated that the bacterial flora after mutation by UV 60?s combined with ultrasonic 10?min had the best oxidation rate of ferrous, the biggest density of cells, and the most activity of total protein. During bioleaching of arsenic-rich gold concentrates, the density of the mutant bacterial cells reached to 1.13 × 108 cells/mL at 15 days, more than 10 times compared with that of the original culture. The extraction of iron reached to 95.7% after 15 days, increased by 9.9% compared with that of the original culture. The extraction of arsenic reached to 92.6% after 12 days, which was increased by 46.1%. These results suggested that optimum combined mutation could improve leaching ability of the bacterial flora more significantly.

Xie, Xuehui; Yuan, Xuewu; Liu, Na; Chen, Xiaoguang; Abdelgadir, Awad; Liu, Jianshe

2013-01-01

104

Subclinical arsenicosis in cattle in arsenic endemic area of West Bengal, India.  

PubMed

Arsenic is ubiquitously found metalloid that commonly contaminates drinking water and agricultural food. To minimise the ecotoxicological effect of arsenic in the environment, it is important to ameliorate the deleterious effects on human and animal health. We investigated the effects of arsenic on cattle by estimating arsenic concentration in biological samples of cattle that consumed contaminated drinking water and feedstuffs directly or indirectly. We have selected arsenic prone village that is Ghentugachi, Nadia district, West Bengal, India, along with arsenic safe control village, Akna in Hoogli district, West Bengal, India. It is found that arsenic is deposited highly in blood, urine and faeces. Agricultural field is contaminated through cattle urine, hair, faeces, cow dung cakes and farmyard manure. Bioconcentration factor and biotransfer factor are two important biomarkers to assess the subclinical toxicity in cattle, as they do not exhibit clinical manifestation like human beings. PMID:22903174

Rana, Tanmoy; Bera, Asit Kumar; Das, Subhashree; Bhattacharya, Debasis; Pan, Diganta; Das, Subrata Kumar

2014-05-01

105

Role of thin descending limb urea transport in renal urea handling and the urine concentrating mechanism  

PubMed Central

Urea transporters UT-A2 and UT-B are expressed in epithelia of thin descending limb of Henle's loop and in descending vasa recta, respectively. To study their role and possible interaction in the context of the urine concentration mechanism, a UT-A2 and UT-B double knockout (UT-A2/B knockout) mouse model was generated by targeted deletion of the UT-A2 promoter in embryonic stem cells with UT-B gene knockout. The UT-A2/B knockout mice lacked detectable UT-A2 and UT-B transcripts and proteins and showed normal survival and growth. Daily urine output was significantly higher in UT-A2/B knockout mice than that in wild-type mice and lower than that in UT-B knockout mice. Urine osmolality in UT-A2/B knockout mice was intermediate between that in UT-B knockout and wild-type mice. The changes in urine osmolality and flow rate, plasma and urine urea concentration, as well as non-urea solute concentration after an acute urea load or chronic changes in protein intake suggested that UT-A2 plays a role in the progressive accumulation of urea in the inner medulla. These results suggest that in wild-type mice UT-A2 facilitates urea absorption by urea efflux from the thin descending limb of short loops of Henle. Moreover, UT-A2 deletion in UT-B knockout mice partially remedies the urine concentrating defect caused by UT-B deletion, by reducing urea loss from the descending limbs to the peripheral circulation; instead, urea is returned to the inner medulla through the loops of Henle and the collecting ducts.

Lei, Tianluo; Zhou, Lei; Layton, Anita T.; Zhou, Hong; Zhao, Xuejian; Bankir, Lise

2011-01-01

106

Correlations between cadmium concentration in urine and exposure variables  

NASA Astrophysics Data System (ADS)

As part of the study 'UMWELT und GESUNDHEIT 1985/86', a representative samples of the population of the Federal Republic of Germany was examined for urinary Cd. A log-linear prediction model based on 2109 cases led to an explained variance portion of R2 equals .32. Strong associations were revealed between urinary cadmium and the smoking history and age of the subjects. This is evidence of the function urinary cadmium has as an indicator of the Cd body burden. However, there are also clear connections with physiological parameters (urinary creatinine and serum urea), which are taken to be a modification of Cd excretion by renal function. The association between urinary Cd and serum urea can also be interpreted as a cadmium-induced renal dysfunction. Urinary Cd concentrations tend to be lower in regions with low industrial nitrogen oxide emissions and high economic dynamics, as well as in non- urban residential structures.

Schwarz, Elmar; Chutsch, Martina; Krause, Christian M.; Schulz, Christine; Thefeld, Wolfgang

1993-03-01

107

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

108

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

109

Selective removal of arsenic and monovalent ions from brackish water reverse osmosis concentrate.  

PubMed

Concentrate disposal and management is a considerable challenge for the implementation of desalination technologies, especially for inland applications where concentrate disposal options are limited. This study has focused on selective removal of arsenic and monovalent ions from brackish groundwater reverse osmosis (RO) concentrate for beneficial use and safe environmental disposal using in situ and pre-formed hydrous ferric oxides/hydroxides adsorption, and electrodialysis (ED) with monovalent permselective membranes. Coagulation with ferric salts is highly efficient at removing arsenic from RO concentrate to meet a drinking water standard of 10 ?g/L. The chemical demand for ferric chloride however is much lower than ferric sulfate as coagulant. An alternative method using ferric sludge from surface water treatment plant is demonstrated as an efficient adsorbent to remove arsenic from RO concentrate, providing a promising low cost, "waste treat waste" approach. The monovalent permselective anion exchange membranes exhibit high selectivity in removing monovalent anions over di- and multi-valent anions. The transport of sulfate and phosphate through the anion exchange membranes was negligible over a broad range of electrical current density. However, the transport of divalent cations such as calcium and magnesium increases through monovalent permselective cation exchange membranes with increasing current density. Higher overall salt concentration reduction is achieved around limiting current density while higher normalized salt removal rate in terms of mass of salt per membrane area and applied energy is attained at lower current density because the energy unitization efficiency decreases at higher current density. PMID:23892312

Xu, Pei; Capito, Marissa; Cath, Tzahi Y

2013-09-15

110

Biooxidation of Two Arsenical Refractory Gold Concentrates and Gold Cyanidation.  

National Technical Information Service (NTIS)

The influence of pulp density, ferric ion concentration and particle size on the tank bioleaching of two kinds of refractory gold concentrates are discussed. The chemistry and mechanism of bioleaching process are also presented. The relationship between o...

Y. Z. Zhang Y. Lu C. Zhang T. Zhao R. Qiu

1995-01-01

111

A Cross-sectional Study of the Impact of Blood Selenium on Blood and Urinary Arsenic Concentrations in Bangladesh  

PubMed Central

Background Arsenic can naturally occur in the groundwater without an anthropogenic source of contamination. In Bangladesh over 50 million people are exposed to naturally occurring arsenic concentrations exceeding the World Health Organization’s guideline of 10 ?g/L. Selenium and arsenic have been shown to facilitate the excretion of each other in bile. Recent evidence suggests that selenium may play a role in arsenic elimination by forming a selenium-arsenic conjugate in the liver before excretion into the bile. Methods A cross-sectional study of 1601 adults and 287 children was conducted to assess the relationship between blood selenium and urinary and blood arsenic in a study population residing in a moderately arsenic-contaminated rural area in Bangladesh. Results The results of this study indicate a statistically significant inverse relationship between blood selenium and urinary arsenic concentrations in both adult and pediatric populations in rural Bangladesh after adjustment for age, sex, Body Mass Index, plasma folate and B12 (in children), and ever smoking and current betel nut use (in adults). In addition, there appears to be a statistically significant inverse relationship between blood selenium and blood arsenic in children. Conclusions Our results suggest that selenium is inversely associated with biomarkers of arsenic burden in both adults and children. These findings support the hypothesis that Se facilitates the biliary elimination of As, possibly via the putative formation of a Se-As conjugate using a glutathione complex. However, laboratory based studies are needed to provide further evidence to elucidate the presence of Se-As conjugate and its role in arsenic elimination in humans.

2013-01-01

112

Concentrations versus amounts of biomarkers in urine: a comparison of approaches to assess pyrethroid exposure  

Microsoft Academic Search

BACKGROUND: Assessment of human exposure to non-persistent pesticides such as pyrethroids is often based on urinary biomarker measurements. Urinary metabolite levels of these pesticides are usually reported in volume-weighted concentrations or creatinine-adjusted concentrations measured in spot urine samples. It is known that these units are subject to intra- and inter-individual variations. This research aimed at studying the impact of these

Marie-Chantale Fortin; Gaétan Carrier; Michčle Bouchard

2008-01-01

113

Spatial distributions of arsenic exposure and mining communities from NHEXAS Arizona  

Microsoft Academic Search

Within the context of the National Human Exposure Assessment Survey (NHEXAS), metals were evaluated in the air, soil, dust, water, food, beverages, and urine of a single respondent. Potential doses were calculated for five metals including arsenic. In this paper, we seek to validate the potential dose calculations through spatial analysis of the data. Others report elevated arsenic concentrations in

MARY KAY O'ROURKE; SÉUMAS P ROGAN; SHAN JIN; GARY L ROBERTSON

1999-01-01

114

Farnesoid X receptor (FXR) gene deficiency impairs urine concentration in mice.  

PubMed

The farnesoid X receptor (FXR) is a ligand-activated transcription factor belonging to the nuclear receptor superfamily. FXR is mainly expressed in liver and small intestine, where it plays an important role in bile acid, lipid, and glucose metabolism. The kidney also has a high FXR expression level, with its physiological function unknown. Here we demonstrate that FXR is ubiquitously distributed in renal tubules. FXR agonist treatment significantly lowered urine volume and increased urine osmolality, whereas FXR knockout mice exhibited an impaired urine concentrating ability, which led to a polyuria phenotype. We further found that treatment of C57BL/6 mice with chenodeoxycholic acid, an FXR endogenous ligand, significantly up-regulated renal aquaporin 2 (AQP2) expression, whereas FXR gene deficiency markedly reduced AQP2 expression levels in the kidney. In vitro studies showed that the AQP2 gene promoter contained a putative FXR response element site, which can be bound and activated by FXR, resulting in a significant increase of AQP2 transcription in cultured primary inner medullary collecting duct cells. In conclusion, the present study demonstrates that FXR plays a critical role in the regulation of urine volume, and its activation increases urinary concentrating capacity mainly via up-regulating its target gene AQP2 expression in the collecting ducts. PMID:24464484

Zhang, Xiaoyan; Huang, Shizheng; Gao, Min; Liu, Jia; Jia, Xiao; Han, Qifei; Zheng, Senfeng; Miao, Yifei; Li, Shuo; Weng, Haoyu; Xia, Xuan; Du, Shengnan; Wu, Wanfu; Gustafsson, Jan-Ĺke; Guan, Youfei

2014-02-11

115

Arsenic Concentrations in Soils Impacted by Dam Failure of Coal-Ash Pond in Zemianske Kostolany, Slovakia  

Microsoft Academic Search

In this study, the concentrations of arsenic were determined in the soils around old coal-ash pond. The soils in the study\\u000a area were severely contaminated with arsenic after dam failure of the coal-ash pond. The mean concentrations of arsenic in\\u000a soils collected from three sampling depths of 0–20, 20–40 and >40 cm were 173, 155 and 426 ?g\\/g, respectively, exceeding greatly\\u000a the

L’ubomír Jurkovi?; Edgar Hiller; Veronika Veselská; Katarína Pet’ková

2011-01-01

116

Normal Values for Arsenic and Selenium Concentrations in Human Lung Tissue  

Microsoft Academic Search

.   Normal values and ranges were determined for arsenic and selenium concentrations in lung and hilus tissue. The study group\\u000a consisted of 50 deceased persons, who were examined by autopsy at the Institute for Pathology of the University of Erlangen-Nuremberg.\\u000a Taking into consideration topographic-anatomical criteria, samples were taken of each lung lobe and the hilar lymph nodes.\\u000a The dried tissue

T. Kraus; G. Quidenus; K. H. Schaller

2000-01-01

117

Reverse osmosis removal of arsenic residues from bioleaching of refractory gold concentrates  

Microsoft Academic Search

The paper deals with the quality of liquid streams likely to arise from bioleaching of gold-bearing arsenical sulphide flotation concentrate and with purification of leachate after lime neutralisation. Synthetic liquors, based on data from an industrial process, were subjected to filtration, reverse osmosis and\\/or resin ion exchange processes under designed conditions in a re-circulating system based on equipment provided by

B. K. C. Chan; A. W. L. Dudeney

2008-01-01

118

Relationship of arsenic concentration with ammonium-nitrogen concentration, oxidation reduction potential and pH of groundwater in arsenic-contaminated areas in Asia  

NASA Astrophysics Data System (ADS)

This study examines how arsenic (As) concentration is related to ammonium-nitrogen (NH4-N) concentration, oxidation reduction potential (ORP) and pH in groundwater to determine if they have common characteristics in groundwater with high As concentrations in the As-contaminated areas of Bangladesh, Nepal, Cambodia and Vietnam. For the groundwater samples having the three highest As concentrations (top three groundwaters) selected as representatives at each location, As and NH4-N concentrations varied, but ORP and pH did not vary by locations. The ORP value of 30-110 mV, indicating the reducing condition, and the neutral to slightly alkaline pH (pH 7.0-7.6) were presumed to be the key conditions for high As concentrations in groundwater of the study areas. According to the ORP (Eh)-pH diagram, the dominant As species in the top three groundwaters from each location was hydrogen arsenate (HAsO42-). Out of the correlations between the four elements for the top three groundwaters in the areas, only the correlation between As and NH4-N concentrations was positive and significant. Thus, it was identified that NH4-N had an effect on increasing As concentration in groundwater.

Kurosawa, Kiyoshi; Egashira, Kazuhiko; Tani, Masakazu

119

Morphine and codeine concentrations in human urine following controlled poppy seeds administration of known opiate content.  

PubMed

Opiates are an important component for drug testing due to their high abuse potential. Proper urine opiate interpretation includes ruling out poppy seed ingestion; however, detailed elimination studies after controlled poppy seed administration with known morphine and codeine doses are not available. Therefore, we investigated urine opiate pharmacokinetics after controlled oral administration of uncooked poppy seeds with known morphine and codeine content. Participants were administered two 45g oral poppy seed doses 8h apart, each containing 15.7mg morphine and 3mg codeine. Urine was collected ad libitum up to 32h after the first dose. Specimens were analyzed with the Roche Opiates II immunoassay at 2000 and 300?g/L cutoffs, and the ThermoFisher CEDIA(®) heroin metabolite (6-acetylmorphine, 6-AM) and Lin-Zhi 6-AM immunoassays with 10?g/L cutoffs to determine if poppy seed ingestion could produce positive results in these heroin marker assays. In addition, all specimens were quantified for morphine and codeine by GC/MS. Participants (N=22) provided 391 urine specimens over 32h following dosing; 26.6% and 83.4% were positive for morphine at 2000 and 300?g/L GC/MS cutoffs, respectively. For the 19 subjects who completed the study, morphine concentrations ranged from <300 to 7522?g/L with a median peak concentration of 5239?g/L. The median first morphine-positive urine sample at 2000?g/L cutoff concentration occurred at 6.6h (1.2-12.1), with the last positive from 2.6 to 18h after the second dose. No specimens were positive for codeine at a cutoff concentration of 2000?g/L, but 20.2% exceeded 300?g/L, with peak concentrations of 658?g/L (284-1540). The Roche Opiates II immunoassay had efficiencies greater than 96% for the 2000 and 300?g/L cutoffs. The CEDIA 6-AM immunoassay had a specificity of 91%, while the Lin-Zhi assay had no false positive results. These data provide valuable information for interpreting urine opiate results. PMID:24887324

Smith, Michael L; Nichols, Daniel C; Underwood, Paula; Fuller, Zachary; Moser, Matthew A; LoDico, Charles; Gorelick, David A; Newmeyer, Matthew N; Concheiro, Marta; Huestis, Marilyn A

2014-08-01

120

Isotopic evidence for a link between agricultural irrigation and high arsenic concentrations in groundwater  

NASA Astrophysics Data System (ADS)

An isotope-based survey was carried out in the Datong Basin, northern China to investigate the hydrogeology of groundwater with high arsenic concentrations. Oxygen isotope (?18O), hydrogen isotope (?D) and radioactive hydrogen isotope (3H) measurements were conducted with the aim of characterizing the groundwater origins and flow dynamics in this arsenic-contaminated groundwater system. Groundwater dating results from 3H measurements show that groundwaters from 20m ~ 70m have a wide range of ages (10a~ 191a), indicating diverse groundwater sources. In contrast, deeper groundwaters (70m ~90m) display a narrower age range (35a ~ 47a). In addition, the shallow-aquifer (<70m), groundwaters exhibit wide variations in ?18O and ?D, from -12.7% to -6.96% and -97.1% to -49.8%, respectively. Deep groundwaters (>70m) possess relatively narrower isotopic ranges and mostly lighter isotopic ratios, from -12.8% to -8.88% and -97.6% to -71.7%, respectively. Comparison with the local meteoric water line shows that groundwater ?18O and ?D values plot with a shallower slope, consistent with the arid-semiarid climate of the Datong Basin, as well as a meteoric origin of the groundwater, and points to precipitation as the dominant source of recharge to the deeper aquifers in the study area. Groundwaters with high arsenic concentrations (100?g/L ~ 309?g/L) mainly occur in aquifers at depths between 20m and 70m, while shallower (<20m) and deeper (>70m) groundwaters carry relatively lower arsenic concentrations (<50?g/L). This result differs from previous studies[1] [2], which documented that groundwaters with high arsenic concentrations occur primarily in the upper aquifers (<50m). It is striking that the groundwaters with elevated arsenic concentrations are also those with the greatest diversity of tritium ages and dispersion of ?18O and ?D values, suggesting that a single process may explain all three data sets. One explanation is that extensive irrigation with groundwaters from various depths (10m~200m) induces the age diversity of the shallow groundwaters. This interpretation is supported by the variations in the ?18O and ?D data. Intensive agricultural activities in the Datong Basin, including extensive pumping of irrigation water from aquifers of various depths, may be changing the hydrology of the shallow groundwater system and directly affecting the arsenic distribution in the groundwater. [1] Shvartsev, S. L. and Wang, Y. X. (2006). "Geochemistry of sodic waters in the Datong intermountain basin, Shanxi Province, northwestern China." Geochemistry International 44(10): 1015-1026. [2] Xie, X. J., Ellis A., Wang, Y. X., et al. (2009). "Geochemistry of redox-sensitive elements and sulfur isotopes in the high arsenic groundwater system of Datong Basin, China." Science of the Total Environment 407(12): 3823-3835.

Li, M.; Wang, Y.; Shock, E.

2011-12-01

121

Vitreous fluid and/or urine glucose concentrations in 1335 civil aviation accident pilot fatalities.  

PubMed

During aviation accident investigations, vitreous fluid and urine samples from pilot fatalities are analyzed for glucose and blood for hemoglobin A(1c) (HbA(1c)) to monitor diabetic pilots and to discover other pilots with undiagnosed/unreported diabetes. The prevalence of elevated glucose concentrations in fatally injured pilots was evaluated by searching the Civil Aerospace Medical Institute's Toxicology Database for the period 1998-2005. Out of 1335 pilots involving 363 vitreous fluid, 365 urine, and 607 vitreous fluid and urine analyses, 43 pilots had elevated glucose in vitreous fluid (>125 mg/dL) and/or in urine (>100 mg/dL). Of the 20 pilots whose blood samples were analyzed, nine had >6% HbA(1c)--four were known diabetics, and five were unknown diabetics. Urinary glucose levels were elevated in all 13 known hyperglycemic pilots. A considerable number of pilots (30 of 43) had elevated glucose and HbA(1c) (5 of 20), suggesting undiagnosed/unreported diabetic conditions. PMID:19302385

Chaturvedi, Arvind K; Botch, Sabra R; Canfield, Dennis V; Forster, Estrella M

2009-05-01

122

[Methodological study on the determination of oxiracetam concentration in serum and urine by HPLC].  

PubMed

A method was developed for the determination of oxiracetam concentration in serum and urine by HPLC. Acyclovir was used as an internal standard. The analytical column was a stainless-steel column (30 mm x 4.6 mm ID) filled with 10 microns Bondapak NH2. A mixture of acetonitrile and water (80: 20) as mobile phase was used at a flow rate of 1 ml.min-1. Detection was performed at 210 nm. The retention times were 6.3 min for oxiracetam and 8.1 min for the internal standard. The lower detection limits were 1 microgram.ml-1 for serum and 20 micrograms.ml-1 for urine. The precision and accuracy within-day and day-to-day for both serum and urine samples ranged from 5.0 to 10.7%. The mean recoveries were 99.7 +/- 5.9% and 99.0 +/- 5.6% for human serum and urine, respectively. The results showed that the method is simple, rapid, sensitive, reliable and good enough to be used in studying the clinical pharmacokinetics of oxiracetam. PMID:7985515

Jiao, X L; Yu, D H; Zou, A Q; Lou, Y Q

1994-01-01

123

The mean concentration of uranium in drinking water, urine, and hair of the occupationally unexposed Finnish working population.  

PubMed

Uranium concentrations in the household water, urine, and hair of the occupationally unexposed Finnish working population were determined using inductively coupled plasma mass spectrometry (ICP-MS). The age of the randomly selected participants ranged from 18 to 66 y. The mean concentrations of uranium in water, urine, and hair were 1.25 microg L(-1), 0.016 microg L(-1), and 0.216 microg g(-1), respectively. The mean uranium concentration in hair of the Finnish working population was from 3- to 15-fold higher than the values reported in the literature, while the mean uranium concentration in urine was similar to those measured elsewhere in Europe. The observed large variation in the uranium concentrations in hair and urine can be explained by the variation in the uranium concentration in drinking water. Exceptionally high concentrations have been measured in private drilled wells in the granite areas of Southern Finland. PMID:19430217

Muikku, Maarit; Puhakainen, Marketta; Heikkinen, Tarja; Ilus, Taina

2009-06-01

124

Concentrations of total and inorganic arsenic in fresh fish, mollusks, and crustaceans from the Gulf of Thailand.  

PubMed

Concentrations of total and inorganic arsenic were determined in 120 samples of eight marine animals collected from the Gulf of Thailand between March and May 2008. Two species with the highest annual catch from each of four marine animal groups were analyzed: fish (Indo-Pacific mackerel and goldstripe sardine), bivalves (green mussel and blood cockle), cephalopods (pharaoh cuttlefish and Indian squid), and crustaceans (banana prawn and swimming crab). Concentrations of inorganic arsenic based on wet weight ranged from 0.012 ?g/g in Indian squids to 0.603 ?g/g in blood cockles. Average percentages of inorganic arsenic with respect to total arsenic ranged from 1.2% in banana prawns to 7.3% in blood cockles. Blood cockles also exhibited the highest levels of total arsenic (5.26 ± 2.01 ?g/g) and inorganic arsenic (0.352 ± 0.148 ?g/g). The levels of inorganic arsenic in the study samples were much lower than the Thai regulatory limit of 2 ?g/g (wet wt) and hence are safe for human consumption. PMID:21375883

Ruangwises, Suthep; Ruangwises, Nongluck

2011-03-01

125

HCG in urine  

MedlinePLUS

Beta-HCG - urine; Human chorionic gonadotropin - urine ... urine is the most concentrated and has enough HCG to be detected. ... Urine HCG tests are a common method of determining if a woman is pregnant. The best time to test ...

126

Treatment of concentrated arsenic(V) solutions by micellar enhanced ultrafiltration with high molecular weight cut-off membrane.  

PubMed

In this work arsenic removal by micellar enhanced ultrafiltration (MEUF) was investigated using cetylpyridinium chloride (CPC) and a cross-flow polyethersulphone (PES) membrane apparatus. The effects of some operating factors on permeate flux, arsenic and CPC rejections were investigated and, in particular, transmembrane pressure, pH, CPC concentration, As concentration and ionic strength. The novel aim of this work is evaluating the possible advantages of using large molecular weight cut-off membrane (100 kDa) and reduced surfactant concentrations (1-3 mM) for treating high fluxes of concentrated arsenic-bearing solutions (6-10 ppm). The experimental results reported in this paper show that PES membrane apparatus with high molecular weight cut-off allowed to treat large fluxes of concentrated arsenic-bearing solutions (6-10 ppm) even by using low surfactant concentration (1-3mM). In particular arsenic removal ranged from 93-98% to 70-74% depending on initial As concentration (6 and 10 ppm, respectively). In addition surfactant leakage in the permeate was always below CMC due to presieving of concentration polarisation layer. The favourable combination of high MWCO membranes and low surfactant concentration can benefit to overall process economics for the lower membrane area requirement (due to greater flux) and the reduced surfactant consumption. PMID:17367924

Beolchini, F; Pagnanelli, F; De Michelis, I; Vegliň, F

2007-09-01

127

Honey increased saliva, plasma, and urine content of total nitrite concentrations in normal individuals.  

PubMed

This study investigated effects of oral honey solution on total nitrite, a stable nitric oxide metabolite, in saliva, plasma, and urine samples collected from normal subjects. Fourteen adult healthy volunteers, 25-50 years old, nine males and three females, were enrolled in the study. Total nitrite was estimated in saliva, plasma, and urine after 14 hours of food fasting. Each subject was then asked to drink honey solution (80 g of raw honey dissolved in 250 mL of water). Saliva and blood samples were collected at 1, 2, and 3 hours after ingestion of honey solution for total nitrite assay, while urine samples were collected after 3 hours for total nitrite assay. The mean total fasting nitrite in saliva was 108 +/- 61.3 micromol/L, which was increased to 130 +/- 62.9, 131.2 +/- 59, and 135.1 +/- 64.3 micromol/L at 1, 2, and 3 hours, respectively. Plasma total nitrite was 22.41 +/- 16.22 micromol/L before drinking honey, which was increased to 34.71 +/- 18.13, 29.38 +/- 14.29, and 33 +/- 13.09 micromol/L at 1, 2, and 3 hours, respectively, after drinking honey. Urine total nitrite before drinking honey was 75.8 +/- 54.79 micromol/L, which was increased to 107.8 +/- 70.83 micromol/L 3 hours after ingestion of honey solution. Although not statistically significant, honey solution showed a tendency to increase total nitrite concentration in different biological fluids from humans, including saliva, plasma, and urine. PMID:15383235

Al-Waili, Noori S; Boni, Nadir S

2004-01-01

128

Predicting arsenic concentrations in the porewaters of buried uranium mill tailings  

NASA Astrophysics Data System (ADS)

The proposed JEB Tailings Management Facility (TMF) to be emplaced below the groundwater table in northern Saskatchewan, Canada, will contain uranium mill tailings from McClean Lake, Midwest and Cigar Lake ore bodies, which are high in arsenic (up to 10%) and nickel (up to 5%). A serious concern is the possibility that high arsenic and nickel concentrations may be released from the buried tailings, contaminating adjacent groundwaters and a nearby lake. Laboratory tests and geochemical modeling were performed to examine ways to reduce the arsenic and nickel concentrations in TMF porewaters so as to minimize such contamination from tailings buried for 50 years and longer. The tests were designed to mimic conditions in the mill neutralization circuit (3 hr tests at 25°C), and in the TMF after burial (5-49 day aging tests). The aging tests were run at, 50, 25 and 4°C (the temperature in the TMF). In order to optimize the removal of arsenic by adsorption and precipitation, ferric sulfate was added to tailings raffinates having Fe/As ratios of less that 3-5. The acid raffinates were then neutralized by addition of slaked lime to nominal pH values of 7, 8, or 9. Analysis and modeling of the test results showed that with slaked lime addition to acid tailings raffinates, relatively amorphous scorodite (ferric arsenate) precipitates near pH 1, and is the dominant form of arsenate in slake limed tailings solids except those high in Ni and As and low in Fe, in which cabrerite-annabergite (Ni, Mg, Fe(II) arsenate) may also precipitate near pH 5-6. In addition to the arsenate precipitates, smaller amounts of arsenate are also adsorbed onto tailings solids. The aging tests showed that after burial of the tailings, arsenic concentrations may increase with time from the breakdown of the arsenate phases (chiefly scorodite). However, the tests indicate that the rate of change decreases and approaches zero after 72 hrs at 25°C, and may equal zero at all times in the TMF at 4°C. Consistent with a kinetic model that describes the rate of breakdown of scorodite to form hydrous ferric oxide, the rate of release of dissolved arsenate to tailings porewaters from slake limed tailings: (1) is proportional to pH above pH 6-7; (2) decreases exponentially as the total molar Fe/As ratio of tailings raffinates is increased from 1/1 to greater than 5/1; and (3) is proportional to temperature with an average Arrhenius activation energy of 13.4 ± 4.2 kcal/mol. Study results suggest that if ferric sulfate and slaked lime are added in the tailings neutralization circuit to give a raffinate Fe/As molar ratio of at least 3-5 and a nominal (initial) pH of 8 (final pH of 7-8), arsenic and nickel concentrations of 2 mg/L or less, are probable in porewaters of individual tailings in the TMF for 50 to 10,000 yrs after tailings disposal. However, the tailings will be mixed in the TMF, which will contain about 35% tailings with Fe/As = 3.0, and 65% tailings with Fe/As = 5.0-7.7. Thus, it seems likely that average arsenic pore water concentrations in the TMF may not exceed 1 mg/L.

Langmuir, Donald; Mahoney, John; MacDonald, Anjali; Rowson, John

1999-10-01

129

The effect of the use of mouthwash on ethylglucuronide concentrations in urine.  

PubMed

Two studies were performed to evaluate the effect of alcohol containing mouthwash on the appearance of ethyl glucuronide (EtG) in urine. In the first study, 9 volunteers were given a 4-oz bottle of mouthwash, which contained 12% ethanol. They gargled with all 4 oz. of the mouthwash at intervals over a 15-min period. All urine samples were collected over the next 24 h. Of 39 provided urine samples, there were 20 > 50 ng/mL, 12 > 100 ng/mL, 5 > 200 ng/mL, 3 > 250 ng/mL, and 1 > 300 ng/mL. The peak concentrations were all within 12 h after the exposure. In the second study, 11 participants gargled 3 times daily for 5 days. The first morning void was collected. Sixteen of the 55 submitted samples contained EtG concentrations of greater than 50 ng/mL. All of them were less than 120 ng/mL. These studies show that incidental exposure to mouthwash containing 12% ethanol, when gargling according to the manufacturer's instructions, can result in urinary EtG values greater than 50 ng/mL. All specimens were negative for ethanol. The limits of detection and quantitation for the EtG testing were 50 ng/mL. PMID:17137525

Costantino, Anthony; Digregorio, E John; Korn, Warren; Spayd, Stephanie; Rieders, Frederic

2006-01-01

130

Response of Leafy Vegetable Kalmi (Water Spinach; Ipomoea aquatica L.) at Elevated Concentrations of Arsenic in Hydroponic Culture  

Microsoft Academic Search

Effects of elevated arsenic (As) concentrations on hydroponic Kalmi (Ipomoea aquatica L.) were investigated. Plants were treated with 0, 10, 25, and 50 ?M As in the greenhouse for 14 days. Arsenic was added\\u000a from sodium meta-arsenite (NaAsO2). Visible toxicity symptom could not easily be recognized without visible growth reduction. Little brown spots on the leaf\\u000a blade were found at 50 ?M As

Molla Rahman Shaibur; Tamanna Islam; Shigenao Kawai

2009-01-01

131

A urine-concentrating defect in 11?-hydroxysteroid dehydrogenase type 2 null mice  

PubMed Central

In aldosterone target tissues, 11?-hydroxysteroid dehydrogenase type 2 (11?HSD2) is coexpressed with mineralocorticoid receptors (MR) and protects the receptor from activation by glucocorticoids. Null mutations in the encoding gene, HSD11B2, cause apparent mineralocorticoid excess, in which hypertension is thought to reflect volume expansion secondary to sodium retention. Hsd11b2?/? mice are indeed hypertensive, but impaired natriuretic capacity is associated with significant volume contraction, suggestive of a urine concentrating defect. Water turnover and the urine concentrating response to a 24-h water deprivation challenge were therefore assessed in Hsd11b2?/? mice and controls. Hsd11b2?/? mice have a severe and progressive polyuric/polydipsic phenotype. In younger mice (?2 mo of age), polyuria was associated with decreased abundance of aqp2 and aqp3 mRNA. The expression of other genes involved in water transport (aqp4, slc14a2, and slc12a2) was not changed. The kidney was structurally normal, and the concentrating response to water deprivation was intact. In older Hsd11b2?/? mice (>6 mo), polyuria was associated with a severe atrophy of the renal medulla and downregulation of aqp2, aqp3, aqp4, slc14a2, and slc12a2. The concentrating response to water deprivation was impaired, and the natriuretic effect of the loop diuretic bumetanide was lost. In older Hsd11b2?/? mice, the V2 receptor agonist desmopressin did not restore full urine concentrating capacity. We find that Hsd11b2?/? mice develop nephrogenic diabetes insipidus. Gross changes to renal structure are observed, but these were probably secondary to sustained polyuria, rather than of developmental origin.

Evans, Louise C.; Livingstone, Dawn E.; Kenyon, Christopher J.; Jansen, Maurits A.; Dear, James W.; Mullins, John J.

2012-01-01

132

Correlation between arsenic concentration in fish and human scalp hair of people living in arsenic-contaminated and noncontaminated areas of Pakistan.  

PubMed

The effects of arsenic (As) toxicity due to frequent consumption of arsenic-contaminated fish was estimated by the analysis of scalp hair of adult males, living near arsenic-contaminated area of Pakistan. For comparison purposes, scalp hair samples were also collected from the inhabitants of Hyderabad city consuming fish species with low levels of As, collected from Indus River. Concentration of As in scalp hair samples was analyzed by using hydride generation atomic absorption spectrometry (HG AAS), after microwave-assisted acid digestion. The accuracy of the As measurement was tested simultaneously analyzing certified reference material. The concentration of As in muscle tissues of fish species were found in the range of 2.11 to 14.1 ?g/g and 1.92 to 12.2 ?g/g, collected from arsenic-contaminated and noncontaminated areas, respectively. Exposed subjects had significantly elevated levels of As in scalp hair samples (0.72-4.94 ?g/g) as compared with referent subjects (0.21-1.484 ?g/g; p?

Shah, Abdul Qadir; Kazi, Tasneem Gul; Baig, Jameel Ahmad; Afridi, Hassan Imran

2011-12-01

133

Concentration of arsenic in water, sediments and fish species from naturally contaminated rivers.  

PubMed

Arsenic (As) may occur in surface freshwater ecosystems as a consequence of both natural contamination and anthropogenic activities. In this paper, As concentrations in muscle samples of 10 fish species, sediments and surface water from three naturally contaminated rivers in a central region of Argentina are reported. The study area is one of the largest regions in the world with high As concentrations in groundwater. However, information of As in freshwater ecosystems and associated biota is scarce. An extensive spatial variability of As concentrations in water and sediments of sampled ecosystems was observed. Geochemical indices indicated that sediments ranged from mostly unpolluted to strongly polluted. The concentration of As in sediments averaged 6.58 ?g/g ranging from 0.23 to 59.53 ?g/g. Arsenic in sediments barely followed (r = 0.361; p = 0.118) the level of contamination of water. All rivers showed high concentrations of As in surface waters, ranging from 55 to 195 ?g/L. The average concentration of As in fish was 1.76 ?g/g. The level of contamination with As differed significantly between species. Moreover, the level of bioaccumulation of As in fish species related to the concentration of As in water and sediments also differed between species. Whilst some fish species seemed to be able to regulate the uptake of this metalloid, the concentration of As in the large catfish Rhamdia quelen mostly followed the concentration of As in abiotic compartments. The erratic pattern of As concentrations in fish and sediments regardless of the invariable high levels in surface waters suggests the existence of complex biogeochemical processes behind the distribution patterns of As in these naturally contaminated ecosystems. PMID:23179469

Rosso, Juan José; Schenone, Nahuel F; Pérez Carrera, Alejo; Fernández Cirelli, Alicia

2013-04-01

134

Assessment of Arsenic Exposure by Measurement of Urinary Speciated Inorganic Arsenic Metabolites in Workers in a Semiconductor Manufacturing Plant  

PubMed Central

Objectives The purpose of this study was to evaluate the exposure to arsenic in preventive maintenance (PM) engineers in a semiconductor industry by detecting speciated inorganic arsenic metabolites in the urine. Methods The exposed group included 8 PM engineers from the clean process area and 13 PM engineers from the ion implantation process area; the non-exposed group consisted of 14 office workers from another company who were not occupationally exposed to arsenic. A spot urine specimen was collected from each participant for the detection and measurement of speciated inorganic arsenic metabolites. Metabolites were separated by high performance liquid chromatography-inductively coupled plasma spectrometry-mass spectrometry. Results Urinary arsenic metabolite concentrations were 1.73 g/L, 0.76 g/L, 3.45 g/L, 43.65 g/L, and 51.32 g/L for trivalent arsenic (As3+), pentavalent arsenic (As5+), monomethylarsonic acid (MMA), dimethylarsinic acid (DMA), and total inorganic arsenic metabolites (As3+ + As5+ + MMA?+?DMA), respectively, in clean process PM engineers. In ion implantation process PM engineers, the concentrations were 1.74 g/L, 0.39 g/L, 3.08 g/L, 23.17 g/L, 28.92 g/L for As3+, As5+, MMA, DMA, and total inorganic arsenic metabolites, respectively. Levels of urinary As3+, As5+, MMA, and total inorganic arsenic metabolites in clean process PM engineers were significantly higher than that in the non-exposed group. Urinary As3+ and As5+ levels in ion implantation process PM engineers were significantly higher than that in non-exposed group. Conclusion Levels of urinary arsenic metabolites in PM engineers from the clean process and ion implantation process areas were higher than that in office workers. For a complete assessment of arsenic exposure in the semiconductor industry, further studies are needed.

2013-01-01

135

Urine Concentrating Ability in Infants with Sickle Cell Disease: Baseline Data from the Phase III Trial of Hydroxyurea (BABY HUG)  

PubMed Central

Background A urine concentrating defect is quite common in sickle cell anemia, has its onset in early childhood, and may be reversible with transfusion. The Pediatric Hydroxyurea Phase III Clinical Trial (BABY HUG) is a double-blind, placebo-controlled trial to assess efficacy of hydroxyurea in preventing organ damage in young children with sickle cell anemia. Procedures Enrolled infants were subjected to parent-supervised fluid deprivation and urine and serum osmolality were determined. Results Of 185 infants age 7.5 – 17.9 months (mean 13.0+/-2.7) and fluid-deprived 7.4+/-2.4 hours (range 4-13), 178 had concurrent determinations of urine and serum osmolality. Mean serum osmolality was 286+/-6 mOsm/kg H2O (range 275-312) and independent of age, height, weight, or duration of fluid deprivation. Urine osmolality (mean 407+/-151, range 58-794 mOsm/ kg H2O) was greater than serum (p<0.0001) and correlated with duration of fluid deprivation (p=0.001). Of 142 (77.2%) who concentrated urine, 54 (29.4%) had urine osmolality > 500 mOsm/kg H2O. Urine osmolality correlated with 99mTc-DTPA clearance (p=0.02) and serum urea nitrogen (p<0.0001), but not with serum osmolality, gender, age, height, weight or serum creatinine. Infants able to produce urine with osmolality > 500 mOsm/kg H2O had higher mean fetal hemoglobin concentrations than did those who could not (p=0.014). Conclusions Even with often limited fluid deprivation, 77.2 percent of young infants with sickle cell anemia were able to concentrate urine. Preservation of concentrating ability was associated with higher fetal hemoglobin concentration. Assessment will be repeated after two years of hydroxyurea or placebo treatment. (ClinicalTrials.gov number, NCT00006400.)

Miller, Scott T.; Wang, Winfred C.; Iyer, Rathi; Rana, Sohail; Lane, Peter; Ware, Russell E.; Li, Daner; Rees, Renee C.

2009-01-01

136

Analysis of arsenic concentrations and correlation in water, soil and aurum by neutron activation analysis technique: a case study in Bagerhat, Bangladesh.  

PubMed

Arsenic concentrations were measured in water, soil and arum (vegetables) samples using the Neutron Activation Analysis method and a correlation between arsenic concentrations in the samples was investigated. The case study at Bagerhat, Bangladesh revealed that almost all the water samples were contaminated by a hazardous level of arsenic that exceeding the World Health Organization recommended value of 0.05 mg/L for Bangladesh. Arsenic concentration of all the water samples ranged from 0.09 to 0.87 mg/L. The concentrations in soil and aurum samples were found to be in the range of 2.22-35.21 and 0.07-0.73 mg/kg, respectively. A positive correlation between arsenic concentrations in soil and water samples was observed. Aurum sample was found to be contaminated by arsenic to a harmful level if the corresponding water sample was also highly contaminated. PMID:20658225

Abdullah, S M A; Islam, M T; Islam, S Z; Hossain, Iqbal; Samsuzzoha, M; Hossain, M D; Latif, S A; Islam, F M A

2010-09-01

137

Normative concentrations of urine thiocyanate in cassava eating communities in Nigeria.  

PubMed

Exposure to cyanide is a major public health problem where highly cyanogenic cassava foods are consumed. Thiocyanate (SCN), the biomarker of exposure to cyanide is present in several foods, and produced endogenously. Concentrations of urine SCN were measured in endemic and non-endemic areas of ataxic polyneuropathy in Nigeria. Cassava food consumption in the endemic area was twice that of non-endemic areas. Geometrical mean (95% CI) urine SCN was 20?µmol/l (18-24) for no consumption of cassava foods, 56?µmol/l (49-64) for daily consumption, 56?µmol/l (48-65) for twice daily consumption and 85?µmol/l (62-117) for thrice daily consumption. 95th percentile reference limit was 125?µmol/l for no consumption of cassava food, but 360?µmol/l for thrice daily consumption. Urine SCN is a useful biomarker of exposure to cyanide from cassava foods. There is strong ecological association of exposure to cyanide and endemicity of ataxic polyneuropathy. PMID:23944969

Oluwole, O S A; Oludiran, A O

2013-12-01

138

Inorganic arsenic exposure and type 2 diabetes mellitus in Mexico  

SciTech Connect

Inorganic arsenic exposure in drinking water has been recently related to diabetes mellitus. To evaluate this relationship the authors conducted in 2003, a case-control study in an arseniasis-endemic region from Coahuila, a northern state of Mexico with a high incidence of diabetes. The present analysis includes 200 cases and 200 controls. Cases were obtained from a previous cross-sectional study conducted in that region. Diagnosis of diabetes was established following the American Diabetes Association criteria, with two fasting glucose values {>=}126 mg/100 ml ({>=}7.0 mmol/l) or a history of diabetes treated with insulin or oral hypoglycemic agents. The next subject studied, subsequent to the identification of a case in the cross-sectional study was taken as control. Inorganic arsenic exposure was measured through total arsenic concentrations in urine, measured by hydride-generation atomic absorption spectrophotometry. Subjects with intermediate total arsenic concentration in urine (63.5-104 {mu}g/g creatinine) had two-fold higher risk of having diabetes (odds ratio=2.16; 95% confidence interval: 1.23, 3.79), but the risk was almost three times greater in subjects with higher concentrations of total arsenic in urine (odds ratio=2.84; 95% confidence interval: 1.64, 4.92). This data provides additional evidence that inorganic arsenic exposure may be diabetogenic.

Coronado-Gonzalez, Jose Antonio [Clinical Epidemiologic Research Unit, General Regional Hospital 1 'Gabriel Mancera', Mexican Institute of the Social Security, Mexico, D.F. (Mexico); Razo, Luz Maria del [Toxicology Departament, Cinvestav, Mexico D.F. (Mexico); Garcia-Vargas, Gonzalo [School of Medicine, Durango State Juarez University, Gomez Palacio, Durango (Mexico); Biomedical Research Center, Coahuila, Autonomous University, Torreon, Coahuila (Mexico); Sanmiguel-Salazar, Francisca [Biomedical Research Center, Coahuila, Autonomous University, Torreon, Coahuila (Mexico); Escobedo-de la Pena, Jorge [Clinical Epidemiologic Research Unit, General Regional Hospital 1 'Gabriel Mancera', Mexican Institute of the Social Security, Mexico, D.F. (Mexico)]. E-mail: jorgeep@servidor.unam.mx

2007-07-15

139

Arsenic speciation analysis of human urine using ion exchange chromatography coupled to inductively coupled plasma mass spectrometry  

Microsoft Academic Search

A sensitive and robust method for the determination of seven inorganic and organic arsenic species was developed using ion exchange chromatography combined with inductively coupled plasma mass spectrometry (IC-ICP-MS). Both anion and cation exchange columns were used in a complementary fashion. Arsenite (As(III)), arsenate (As(V)), monomethylarsonic acid (MMA(V)) and dimethylarsinic acid (DMA(V)) were selectively separated by an anion exchange column

Ruimin Xie; Willie Johnson; Steve Spayd; Gene S. Hall; Brian Buckley

2006-01-01

140

Elk exposure to arsenic in geothermal watersheds of Yellowstone National Park, USA.  

PubMed

Geothermal activity in Yellowstone National Park (WY, USA) (YNP) results in elevated levels of arsenic in surface waters, aquatic vegetation, and sediments in the Upper Madison River Basin. This study was conducted to determine concentrations of arsenic in the tissues, feces, and rumen contents of elk (Cervus elaphus) residing in the Madison-Firehole (MF) River basin, and to evaluate potential arsenic exposure pathways. Concentrations of total arsenic in MF elk were significantly higher than in control elk populations, and analysis of arsenic in surface waters, elk forage, sediments, and soils suggests that the predominant arsenic exposure pathways are forage species found in aquatic and riparian habitats. Analysis of arsenic species in selected plant and elk samples indicated that the ingested forms of arsenic are predominantly inorganic, while the appearance of dimethylarsonate in elk rumen and feces suggests that arsenic is subject to methylation reactions after ingestion, potentially contributing to arsenic detoxification. Arsenic:creatinine ratios of elk urine samples analyzed across three different winters increased during winter progression and were correlated with total snow water equivalent as an index of winter severity. Exposure to arsenic and other trace elements (fluorine) may contribute to the previously observed decreased life expectancy of MF elk relative to control populations. PMID:15095895

Kocar, Benjamin D; Garrott, Robert A; Inskeep, William P

2004-04-01

141

Pre-cancerous changes in urothelial endocytic vesicle leakage, fatty acid composition, and As and associated element concentrations after arsenic exposure.  

PubMed

The urothelium covering the luminal surface of the urinary bladder has developed an efficient permeability barrier that protects it against the back-flow of toxins eliminated in the urine. The subapical endocytic vesicles containing the urinary bladder fluid phase are formed during the micturition cycle by endocytosis processes of the superficial cells. In normal conditions, the permeability barrier of the endocytic vesicles blocks the passage of the fluid phase to the cellular cytoplasm and the fluid is recycled to the bladder lumen. The aim of this work was to investigate the alteration of the endocytic vesicle membrane permeability barrier to toxins such as iAs (inorganic arsenic) administered in drinking water. By using an induced endocytosis model and the fluorescence requenching technique, it is shown that the exposure of rats to ingestion of water containing iAs not only induced pre-cancerous morphological changes, but allowed the differential leakage of an endocytosed fluorescent marker, HPTS, and its quencher, DPX, (hydroxypyrene-1,3,6-trisulfonic acid and p-xylene-bis-pyridinium bromide, respectively) out of the vesicular lumen. The leakage of the cationic DPX was almost complete, while the release of the anionic HPTS molecule was partial and higher in arsenic-treated-rats than in controls. Such membrane alteration would allow the toxins to elude the permeability barrier and to leak out of the endocytic vesicles, thus establishing a "bypass" to the permeability barrier. The retention of As in the urinary bladder, assessed by synchrotron radiation X-ray fluorescence spectrometry (SR-?XRF), was lower than the kidney accumulation of arsenic previously observed by our group and was accompanied by altered concentrations of K, Ca, Fe, Cu and Zn, all ions related to cellular metabolism. The results support the hypothesis that low amounts of endocytosed As can accumulate in the interior of the urothelial superficial cells and initiate the cytotoxic effects reflected in the morphological alterations observed. PMID:21440029

Grasso, E J; Bongiovanni, G A; Pérez, R D; Calderón, R O

2011-06-18

142

Impact of enzymatic and alkaline hydrolysis on CBD concentration in urine  

PubMed Central

A sensitive and specific analytical method for cannabidiol (CBD) in urine was needed to define urinary CBD pharmacokinetics after controlled CBD administration, and to confirm compliance with CBD medications including Sativex—a cannabis plant extract containing 1:1 ?9-tetrahydrocannabinol (THC) and CBD. Non-psychoactive CBD has a wide range of therapeutic applications and may also influence psychotropic smoked cannabis effects. Few methods exist for the quantification of CBD excretion in urine, and no data are available for phase II metabolism of CBD to CBD-glucuronide or CBD-sulfate. We optimized the hydrolysis of CBD-glucuronide and/or -sulfate, and developed and validated a GC-MS method for urinary CBD quantification. Solid-phase extraction isolated and concentrated analytes prior to GC-MS. Method validation included overnight hydrolysis (16 h) at 37 °C with 2,500 units ?-glucuronidase from Red Abalone. Calibration curves were fit by linear least squares regression with 1/x2 weighting with linear ranges (r2>0.990) of 2.5–100 ng/mL for non-hydrolyzed CBD and 2.5–500 ng/mL for enzyme-hydrolyzed CBD. Bias was 88.7–105.3 %, imprecision 1.4–6.4 % CV and extraction efficiency 82.5–92.7 % (no hydrolysis) and 34.3–47.0 % (enzyme hydrolysis). Enzyme-hydrolyzed urine specimens exhibited more than a 250-fold CBD concentration increase compared to alkaline and non-hydrolyzed specimens. This method can be applied for urinary CBD quantification and further pharmacokinetics characterization following controlled CBD administration.

Bergamaschi, Mateus M.; Barnes, Allan; Queiroz, Regina H. C.; Hurd, Yasmin L.

2013-01-01

143

Ethyl glucuronide concentrations in two successive urinary voids from drinking drivers: relationship to creatinine content and blood and urine ethanol concentrations  

Microsoft Academic Search

The concentrations of alcohol in blood (BAC) and two successive urine voids (UAC) from 100 drunk drivers were compared with the concentration of ethyl glucuronide (EtG), a minor metabolite of ethanol in urine, and the urinary creatinine content as an indicator of dilution. The subjects consisted of 87 men with mean age 42.2±14.2 years (±standard deviation, S.D.) and 13 women

J Bergström; A Helander; A. W Jones

2003-01-01

144

Application of geostatistics with Indicator Kriging for analyzing spatial variability of groundwater arsenic concentrations in Southwest Bangladesh.  

PubMed

This article seeks to explore the spatial variability of groundwater arsenic (As) concentrations in Southwestern Bangladesh. Facts about spatial pattern of As are important to understand the complex processes of As concentrations and its spatial predictions in the unsampled areas of the study site. The relevant As data for this study were collected from Southwest Bangladesh and were analyzed with Flow Injection Hydride Generation Atomic Absorption Spectrometry (FI-HG-AAS). A geostatistical analysis with Indicator Kriging (IK) was employed to investigate the regionalized variation of As concentration. The IK prediction map shows a highly uneven spatial pattern of arsenic concentrations. The safe zones are mainly concentrated in the north, central and south part of the study area in a scattered manner, while the contamination zones are found to be concentrated in the west and northeast parts of the study area. The southwest part of the study area is contaminated with a highly irregular pattern. A Generalized Linear Model (GLM) was also used to investigate the relationship between As concentrations and aquifer depths. A negligible negative correlation between aquifer depth and arsenic concentrations was found in the study area. The fitted value with 95 % confidence interval shows a decreasing tendency of arsenic concentrations with the increase of aquifer depth. The adjusted mean smoothed lowess curve with a bandwidth of 0.8 shows an increasing trend of arsenic concentration up to a depth of 75 m, with some erratic fluctuations and regional variations at the depth between 30 m and 60 m. The borehole lithology was considered to analyze and map the pattern of As variability with aquifer depths. The study has performed an investigation of spatial pattern and variation of As concentrations. PMID:21879851

Hassan, M Manzurul; Atkins, Peter J

2011-01-01

145

A systematic review of the ability of urine concentration to distinguish antipsychotic- from psychosis-induced hyponatremia.  

PubMed

Life-threatening hyponatremia in psychotic patients is common and typically is attributable to either antipsychotic medication or to acute psychosis in those with the polydipsia-hyponatremia syndrome. The preferred treatment for one situation may worsen the hyponatremia if caused by the other situation. Hence it is critical to distinguish between these two possibilities. Case reports and series were identified through electronic databases. Fifty-four cases of hyponatremia without recognized causes in psychotic patients were divided into those with dilute (concentrated (>plasma osmolality) urine. The distribution of urine concentration and measures likely to be associated with psychotic illness and its treatment were compared in both groups. Naranjo?s scale was utilized to determine the probability hyponatremia was drug-induced. Urine osmolality fit a bimodal distribution (intersection 219mOsm/kg) better than a unimodal distribution. 'Probable' drug-induced cases occurred 6.8 (95%CI=1.6-28.9) times more often in those with concentrated urine. Acute psychotic exacerbations occurred 4.5 (95%CI=0.4-54.1) times more often in those with dilute urine. These findings, as well as several other trends in the data, indicate that measures of urine concentration can help distinguish between antipsychotic-induced and psychosis-induced hyponatremia. PMID:24726819

Atsariyasing, Wanlop; Goldman, Morris B

2014-07-30

146

PATHWAY OF INORGANIC ARSENIC METABOLISM  

EPA Science Inventory

A remarkable aspect of the metabolism of inorganic arsenic in humans is its conversion to methylated metabolites. These metabolites account for most of the arsenic found in urine after exposure to inorganic arsenic. At least some of the adverse health effects attributed to inor...

147

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

148

Plasma and urine concentrations of marbofloxacin following single subcutaneous administration to cats.  

PubMed

The pharmacokinetic properties of marbofoxacin, a third generation fluoroquinolone, were investigated in 12 healthy adult cats after single subcutaneous (SC) administration of 2 mg/kg BW (Part I, n=8 cats) and 4 mg/kg BW (Part II, n=4 cats). In each part of the study blood and urine samples were collected before treatment and thereafter for 5 days. The plasma and urine concentrations of marbofloxacin were determined by HPLC with UV detection. Pharmacokinetic calculations were performed for each treated animal using an open one-compartment-model with first-order elimination after SC dosing. Marbofloxacin in plasma (means): Maximum concentrations (Cmax) of about 1.2 and 3.0 microg/ml were measured 2.3 and 4 hours (tmax) after dosing of 2 and 4 mg/kg BW, respectively. Elimination from the body was low with a total clearance (Cl/F) of approximately 0.1 l/h/kg for both dosages. The half-life (t 1/2) for this process was calculated with 8-10 hours. AUC increased almost proportional when doubling the dose, i.e., 19.77 +/- 6.25 microg * h/ml (2 mg/kg BW) and 51.26 +/- 11.83 microg * h/ml (4 mg/kg BW). Plasma kinetics measured were in accordance with data from literature. Marbofloxacin in urine (means): Maximum drug concentrations were detected 4 and 8 hours after dosing with 70 microg/ml (2 mg/kg BW) and 160 microg/ml (4 mg/kg BW), respectively. Inhibitory effects of the urinary matrix on the antimicrobial activity of the drug were taken into account when performing PK/PD calculations. However, a concentration-dependent bactericidal activity (Cmax/MIC > 8-10) which is claimed for fluoroquinolones was sufficiently met with focus on Escherichia (E.) coli (MIC90 0.5 microg/ml). In the same matrix a threshold value of 1.0 microg/ml was undercut 82 and 116 hours after SC dosing, respectively. Hence, a time-dependent bacteria killing kinetic (T > MIC) which may be of relevance for some Gram-positive germs like Staphylococcus spp. (MIC90 1.0 microg/ml) should be covered, too. PMID:21306059

Kietzmann, Manfred; Niedorf, Frank; Kramer, Sabine; Hoffmann, Marina; Schneider, Marc; Vallé, Marc; Pankow, Rüdiger

2011-01-01

149

Airborne arsenic and urinary excretion of arsenic metabolites during boiler cleaning operations in a Slovak coal-fired power plant.  

PubMed Central

Little information is available on the relationship between occupational exposure to inorganic arsenic in coal fly ash and urinary excretion of arsenic metabolites. This study ws undertaken in a coal-fired power plant in Slovakia during a routine maintenance outage. Arsenic was measured in the breathing zone of workers during 5 consecutive workdays, and urine samples were obtained for analysis of arsenic metabolites--inorganic arsenic (Asi), monomethylarsonic acid (MMA), and dimethylarsinic acid (DMA)--prior to the start of each shift. Results from a small number of cascade impactor air samples indicated that approximately 90% of total particle mass and arsenic was present in particle size fractions >/= 3.5 micron. The 8-hr time-weighted average (TWA) mean arsenic air concentration was 48.3 microg/m3 (range 0.17-375.2) and the mean sum of urinary arsenic (SigmaAs) metabolites was 16.9 microg As/g creatinine (range 2.6-50.8). For an 8-hr TWA of 10 microg/m3 arsenic from coal fly ash, the predicted mean concentration of the SigmaAs urinary metabolites was 13.2 microg As/G creatinine [95% confidence interval (CI), 10.1-16.3). Comparisons with previously published studies of exposure to arsenic trioxide vapors and dusts in copper smelters suggest that bioavailability of arsenic from airborne coal fly ash (as indicated by urinary excretion) is about one-third that seen in smelters and similar settings. Arsenic compound characteristics, matrix composition, and particle size distribution probably play major roles in determining actual uptake of airborne arsenic. Images Figure 1. A Figure 1. B Figure 2.

Yager, J W; Hicks, J B; Fabianova, E

1997-01-01

150

Fate of arsenic in swine waste from concentrated animal feeding operations.  

PubMed

Swine diets are often supplemented by organoarsenicals, such as 3-nitro-4-hydroxyphenylarsonic acid (roxarsone) to treat animal diseases and promote growth. Recent work reported roxarsone degradation under anaerobic conditions in poultry litter, but no such data exist for swine wastes typically stored in lagoons nearby concentrated animal feeding operations (CAFOs). The objectives of this study were to: (i) characterize a suite of swine wastes collected from 19 randomly selected CAFOs for soluble arsenate [As(V)], arsenite [As(III)], dimethylarsenic acid (DMA), monomethylarsonic acid (MMA), 3-amino-4-hydroxyphenylarsonic acid (3-HPPA), p-arsanilic acid, and roxarsone, and (ii) determine the geochemical fate of roxarsone in storage lagoons nearby CAFOs. Swine waste suspensions were spiked with roxarsone and incubated under dark/light and aerobic/anaerobic conditions to monitor roxarsone degradation kinetics. Arsenic speciation analysis using liquid chromatography and inductively coupled plasma mass spectrometry (LC-ICPMS) illustrated the prevalence of As(V) in swine waste suspensions. Roxarsone underwent degradation to either organoarsenicals (3-HPPA) or As(V) and a number of unidentified metabolites. Roxarsone degradation occurred under anaerobic conditions for suspensions low in solids content, but suspensions higher in solids content facilitated roxarsone degradation under both anaerobic and aerobic conditions. Increased solids content enhanced roxarsone degradation kinetics under aerobic conditions. According to current waste storage and sampling practices, arsenic in swine wastes stored in lagoons has been overlooked as a possible environmental health issue. PMID:18574196

Makris, Konstantinos C; Quazi, Shahida; Punamiya, Pravin; Sarkar, Dibyendu; Datta, Rupali

2008-01-01

151

Blood Arsenic and Cadmium Concentrations in End-Stage Renal Disease Patients who were on Maintenance Haemodialysis.  

PubMed

Background: In India, there is a rising burden of chronic diseases like hypertension and diabetes. It has been estimated that 25-40% of these patients are likely to develop chronic kidney disease (CKD), with a significant percentage requiring renal replacement therapy. Haemodialysis is the most common method which is used to treat advanced and permanent kidney failure. Derangements in the metabolism of several toxic and trace elements such as antimony, arsenic cadmium, molybdenum, nickel, and selenium have been reported for several decades in patients with chronically reduced renal functions. Overall, the available literature suggests that the blood levels of some elements such as cadmium, chromium, fluorine, iodine, lead, or vanadium are high in end-stage renal disease (ESRD). Aim and Objectives: Our aim was to study the levels of blood arsenic and cadmium in ESRD patients who were on maintenance haemodialysis (MHD), and to study whether there was any relationship between their concentrations and the duration of the MHD. Methods: The blood lead levels were determined in 50 healthy subjects with normal renal functions and in 50 patients with ESRD, who were on MHD. None of them had any history of smoking or any industrial exposure. Results: The results of the study revealed that the blood arsenic and cadmium concentrations were higher in the ESRD patients who were on MHD than in the healthy adults. The blood arsenic and cadmium concentrations were found to increase with the duration of the MHD. Conclusion: The mild increase in the blood arsenic and cadmium concentrations, with an increase in the duration of the MHD in the study population, may be viewed in the wider context, that a prolonged exposure to arsenic and cadmium, even at low levels, may result in renal damage and/or progression of an already existing CKD. PMID:23814716

Palaneeswari M, Subha; Rajan, P M Abraham Sam; Silambanan, Santhi; Jothimalar

2013-05-01

152

Catecholamines - urine  

MedlinePLUS

Dopamine-urine test; Epinephrine-urine test; Adrenalin-urine test; Urine metanephrine; Normetanephrine; Norepinephrine-urine test; Urine catecholamines; VMA; HVA; Metanephrine; Homovanillic acid (HVA)

153

Arsenic Exposure, Diabetes Prevalence, and Diabetes Control in the Strong Heart Study  

PubMed Central

This study evaluated the association of arsenic exposure, as measured in urine, with diabetes prevalence, glycated hemoglobin, and insulin resistance in American Indian adults from Arizona, Oklahoma, and North and South Dakota (1989–1991). We studied 3,925 men and women 45–74 years of age with available urine arsenic measures. Diabetes was defined as a fasting glucose level of 126 mg/dL or higher, a 2-hour glucose level of 200 mg/dL or higher, a hemoglobin A1c (HbA1c) of 6.5% or higher, or diabetes treatment. Median urine arsenic concentration was 14.1 µg/L (interquartile range, 7.9–24.2). Diabetes prevalence was 49.4%. After adjustment for sociodemographic factors, diabetes risk factors, and urine creatinine, the prevalence ratio of diabetes comparing the 75th versus 25th percentiles of total arsenic concentrations was 1.14 (95% confidence interval: 1.08, 1.21). The association between arsenic and diabetes was restricted to participants with poor diabetes control (HbA1c ?8%). Arsenic was positively associated with HbA1c levels in participants with diabetes. Arsenic was not associated with HbA1c or with insulin resistance (assessed by homeostatic model assessment to quantify insulin resistance) in participants without diabetes. Urine arsenic was associated with diabetes control in a population from rural communities in the United States with a high burden of diabetes. Prospective studies that evaluate the direction of the relation between poor diabetes control and arsenic exposure are needed.

Gribble, Matthew O.; Howard, Barbara V.; Umans, Jason G.; Shara, Nawar M.; Francesconi, Kevin A.; Goessler, Walter; Crainiceanu, Ciprian M.; Silbergeld, Ellen K.; Guallar, Eliseo; Navas-Acien, Ana

2012-01-01

154

Arsenic exposure, diabetes prevalence, and diabetes control in the Strong Heart Study.  

PubMed

This study evaluated the association of arsenic exposure, as measured in urine, with diabetes prevalence, glycated hemoglobin, and insulin resistance in American Indian adults from Arizona, Oklahoma, and North and South Dakota (1989-1991). We studied 3,925 men and women 45-74 years of age with available urine arsenic measures. Diabetes was defined as a fasting glucose level of 126 mg/dL or higher, a 2-hour glucose level of 200 mg/dL or higher, a hemoglobin A1c (HbA1c) of 6.5% or higher, or diabetes treatment. Median urine arsenic concentration was 14.1 µg/L (interquartile range, 7.9-24.2). Diabetes prevalence was 49.4%. After adjustment for sociodemographic factors, diabetes risk factors, and urine creatinine, the prevalence ratio of diabetes comparing the 75th versus 25th percentiles of total arsenic concentrations was 1.14 (95% confidence interval: 1.08, 1.21). The association between arsenic and diabetes was restricted to participants with poor diabetes control (HbA1c ?8%). Arsenic was positively associated with HbA1c levels in participants with diabetes. Arsenic was not associated with HbA1c or with insulin resistance (assessed by homeostatic model assessment to quantify insulin resistance) in participants without diabetes. Urine arsenic was associated with diabetes control in a population from rural communities in the United States with a high burden of diabetes. Prospective studies that evaluate the direction of the relation between poor diabetes control and arsenic exposure are needed. PMID:23097256

Gribble, Matthew O; Howard, Barbara V; Umans, Jason G; Shara, Nawar M; Francesconi, Kevin A; Goessler, Walter; Crainiceanu, Ciprian M; Silbergeld, Ellen K; Guallar, Eliseo; Navas-Acien, Ana

2012-11-15

155

Multi-trace element levels and arsenic speciation in urine of e-waste recycling workers from Agbogbloshie, Accra in Ghana.  

PubMed

To understand human contamination by multi-trace elements (TEs) in electrical and electronic waste (e-waste) recycling site at Agbogbloshie, Accra in Ghana, this study analyzed TEs and As speciation in urine of e-waste recycling workers. Concentrations of Fe, Sb, and Pb in urine of e-waste recycling workers were significantly higher than those of reference sites after consideration of interaction by age, indicating that the recycling workers are exposed to these TEs through the recycling activity. Urinary As concentration was relatively high, although the level in drinking water was quite low. Speciation analysis of As in human urine revealed that arsenobetaine and dimethylarsinic acid were the predominant As species and concentrations of both species were positively correlated with total As concentration as well as between each other. These results suggest that such compounds may be derived from the same source, probably fish and shellfish and greatly influence As exposure levels. To our knowledge, this is the first study on human contamination resulting from the primitive recycling of e-waste in Ghana. This study will contribute to the knowledge about human exposure to trace elements from an e-waste site in a less industrialized region so far scantly covered in the literature. PMID:22446112

Asante, Kwadwo Ansong; Agusa, Tetsuro; Biney, Charles Augustus; Agyekum, William Atuobi; Bello, Mohammed; Otsuka, Masanari; Itai, Takaaki; Takahashi, Shin; Tanabe, Shinsuke

2012-05-01

156

The use of hydrogel microparticles to sequester and concentrate bacterial antigens in a urine test for Lyme disease.  

PubMed

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 10 mL 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. PMID:21035184

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

2011-02-01

157

Respiratory effect related to exposure of different concentrations of arsenic in drinking water in West Bengal, India.  

PubMed

Arsenic toxicity due to drinking of arsenic contaminated water has been one of the worst environmental health hazards. High levels of arsenic have been reported in different natural water sources from West Bengal for more than two decades. Groundwater contamination by arsenic and its adverse effects on the health of a big population in nine districts of West Bengal have been reported. The problems found were mainly related to skin and respiratory, digestive, cardiovascular and nervous systems. The respiratory effects are largely confined to those who had the skin lesion. The present study was undertaken to evaluate the respiratory effects of exposure to different levels of arsenic in drinking water. The water samples were collected from different tube wells and wells in the study area. Analysis of arsenic was done by Atomic Absorption Spectrophotometer with hydride generation system. Based on the consumption of arsenic concentrations in drinking water the populations were divided into three categories, i.e., <=50 microg/L, >50 - <= 150 microg/L and >150 microg/L. Standard techniques of medical examination were applied to elicit signs and recorded in the pre-designed proforma. A written consent was taken from each subject for their voluntary participation in the study. 112 subjects were investigated. The respiratory effect was evaluated by measuring the pulmonary function test (PFT). Vital Capacity (VC) and Forced Vital Capacity (FVC) were measured by Spirovit-SP-10 (Schiller Health Care Pvt Ltd., Switzerland) and Peak Expiratory Flow Rate by Wrights Peak Flow Meter (Clement and Clarke, UK). The PFT values showed gradual decrement among the males following skin pigmentation, keratosis and arsenicosis. The respiratory function impairment among the male subjects found as restrictive type (26.41%), obstructive type (3.77%) and combined type (7.54%), whereas in females only the restrictive type of impairment (10.16%) was found. Restrictive type of impairments among the subjects increased as the concentration of arsenic in drinking water increased, in males 15.78%, 29.41% and 35.29% and in females 4.54%, 5.00% and 23.52% respectively. The pathophysiologic mechanism, by which ingested arsenic leads to impairments of lung function and increased respiratory symptoms, is yet to be understood and needs further investigation. PMID:21114123

Chattopadhyay, B P; Mukherjee, A K; Gangopadhyay, P K; Alam, J; Roychowdhury, A

2010-04-01

158

Multivariate statistical analysis of arsenic and selenium concentrations in groundwaters from south-central Nevada and Death Valley, California  

Microsoft Academic Search

Arsenic and selenium concentrations along with the major solutes were measured in ground-waters sampled from springs in Pahranagat Valley and Ash Meadows, Nevada, Death Valley, California, and from wells from the Nevada Test Site and Yucca Mountain, Nevada. The multivariate statistical technique correspondence analysis was applied to the data to determine relationships between the groundwaters from these areas, the aquifer

Kevin H. Johannesson; Klaus J. Stetzenbach; David K. Kreamer; Vernon F. Hodge

1996-01-01

159

Geographical and habitat differences in concentrations of copper, zinc and arsenic in eggshells of the Rook Corvus frugilegus in Poland  

Microsoft Academic Search

Levels of copper, zinc, and arsenic were analyzed in the Rook Corvus frugilegus eggshells from 43 breeding colonies located in different parts of Poland. The average [95% confidence interval (CI)] level\\u000a of copper was found to be 8.13 (0.64–15.62) ppm, of zinc 13.81 (7.99–19.62) ppm, and of arsenic 32.57 (25.60–39.54) ppm. The\\u000a concentration levels of these metals varied widely in

Grzegorz Or?owski; Zbigniew Kasprzykowski; Wojciech Dobicki; Przemys?aw Pokorny; Ryszard Polecho?ski

2010-01-01

160

Association between risk of birth defects occurring level and arsenic concentrations in soils of Lvliang, Shanxi province of China.  

PubMed

The risk of birth defects is generally accredited with genetic factors, environmental causes, but the contribution of environmental factors to birth defects is still inconclusive. With the hypothesis of associations of geochemical features distribution and birth defects risk, we collected birth records and measured the chemical components in soil samples from a high prevalence area of birth defects in Shanxi province, China. The relative risk levels among villages were estimated with conditional spatial autoregressive model and the relationships between the risk levels of the villages and the 15 types of chemical elements concentration in the cropland and woodland soils were explored. The results revealed that the arsenic levels in cropland soil showed a significant association with birth defects occurring risk in this area, which is consistent with existing evidences of arsenic as a teratogen and warrants further investigation on arsenic exposure routine to birth defect occurring risk. PMID:24769413

Wu, Jilei; Zhang, Chaosheng; Pei, Lijun; Chen, Gong; Zheng, Xiaoying

2014-08-01

161

Environmental arsenic exposure, selenium and sputum alpha-1 antitrypsin  

PubMed Central

Exposure to arsenic in drinking water is associated with increased respiratory disease. Alpha-1 antitrypsin (AAT) protects the lung against tissue destruction. The objective of this study was to determine whether arsenic exposure is associated with changes in airway AAT concentration and whether this relationship is modified by selenium. A total of 55 subjects were evaluated in Ajo and Tucson, Arizona. Tap water and first morning void urine were analyzed for arsenic species, induced sputum for AAT and toenails for selenium and arsenic. Household tap-water arsenic, toenail arsenic and urinary inorganic arsenic and metabolites were significantly higher in Ajo (20.6 ± 3.5 µg/l, 0.54 ± 0.77 µg/g and 27.7 ± 21.2 µg/l, respectively) than in Tucson (3.9 ± 2.5 µg/l, 0.16 ± 0.20 µg/g and 13.0 ± 13.8 µg/l, respectively). In multivariable models, urinary monomethylarsonic acid (MMA) was negatively, and toenail selenium positively associated with sputum AAT (P = 0.004 and P = 0.002, respectively). In analyses stratified by town, these relationships remained significant only in Ajo, with the higher arsenic exposure. Reduction in AAT may be a means by which arsenic induces respiratory disease, and selenium may protect against this adverse effect.

Burgess, Jefferey L.; Kurzius-Spencer, Margaret; Poplin, Gerald S.; Littau, Sally R.; Kopplin, Michael J.; Sturup, Stefan; Boitano, Scott; Lantz, R. Clark

2014-01-01

162

Determination of total arsenic concentrations in nails by inductively coupled plasma mass spectrometry  

Microsoft Academic Search

The analysis of trace elements in biological samples will extend our understanding of the impact that environmental exposure\\u000a to these elements has on human health. Measuring arsenic content in nails has proven useful in studies evaluating the chronic\\u000a body burden of arsenic. In this study, we developed methodology with inductively coupled plasma-mass spectrometry (ICP-MS)\\u000a for the determination of total arsenic

Kuei-Ling Belinda Chen; Chitra J. Amarasiriwardena; David C. Christiani

1999-01-01

163

Determination of inorganic arsenic species by flow injection hydride generation atomic absorption spectrometry with variable sodium tetrahydroborate concentrations*1  

NASA Astrophysics Data System (ADS)

This work describes a study on the determination of inorganic arsenic species in ground water and synthetic experimental matrices, using a flow injection system with on-line hydride generation device coupled to an atomic absorption spectrometer with flame-heated quartz atomizer (FI HG AAS). Specific trivalent arsenic determination is based on the slow kinetics of As(V) on the hydride generation reaction using sufficiently low concentrations of sodium tetrahydroborate (NaBH 4) as reductant in highly acidic conditions (pH<0). Under these conditions, the efficiency of hydride generation from As(V) is much lower than that from As(III). The pentavalent form is determined by the difference between total inorganic arsenic and As(III). As(V) interferences were studied using As(III) solutions ranging from 0% to 50% of total inorganic As. The optimized NaBH 4 concentration was 0.035% (w/v). The detection limit was 1.4 ?g l -1 As(III). As(V) interferences were 6% in the case of water samples with 6 ?g l -1 As(III) in the presence of 54 ?g l -1 As(V) (i.e. 10% As(III)). Interferences of methylated arsenic species (MMA and DMA) were evaluated. Speciation method was satisfactorily applied to 20 field arsenical water samples from Santa Fe, Argentina, with values ranging from 30 to 308 ?g l -1 total As. We found from 0% to 36% As(III) in the 20 field samples. The developed methodology constitutes an economic, simple and reliable way to evaluate inorganic arsenic distribution in underground waters or similar systems with negligible or no content of organoarsenicals.

Sigrist, Mirna E.; Beldoménico, Horacio R.

2004-07-01

164

Total and bioavailable arsenic concentration in arid soils and its uptake by native plants from the pre-Andean zones in Chile.  

PubMed

Arsenic is the most important contaminant of the environment in northern Chile. Soil samples and plant organs from three native plant species, Pluchea absinthioides, Atriplex atacamensis and Lupinus microcarpus, were collected from arid zones in order to determine the total and bioavailable arsenic concentrations in soils and to assess the bioconcentration factor (BCF) and transport index (Ti) of arsenic in the plants. Total arsenic concentrations in soils (pH 8.3-8.5) where A. atacamensis and P. absinthioides were collected, reached levels considered to be contaminated (54.3 ± 15.4 and 52.9 ± 9.9 mg kg?ą, respectively), and these values were approximately ten times higher than in soils (pH 7.6) where L. microcarpus was collected. Bioavailable arsenic ranged from 0.18 to 0.42% of total arsenic concentration. In the three plant species, arsenic concentration in leaves were significantly (p ? 0.05) higher than in roots. L. microcarpus showed the highest arsenic concentration in its leaves (9.7 ± 1.6 mg kg?ą) and higher values of BCF (1.8) and Ti (6.1), indicating that this species has a greater capacity to accumulate and translocate the metalloid to the leaf than do the other species. PMID:21484519

Díaz, O; Tapia, Y; Pastene, R; Montes, S; Núńez, N; Vélez, D; Montoro, R

2011-06-01

165

Arsenic is cytotoxic at micromolar concentration, but does not inhibit purified human DNA repair enzymes at less than millimolar concentrations  

SciTech Connect

Arsenic is a well-known human carcinogen, but not a mutagen. However it can act as a co-mutagen with UV and alkylating agents, and has been shown to inhibit DNA repair. The activities of several purified human enzymes involved in DNA repair have been tested in the presence of inorganic arsenite [As(III)] and arsenate [As(V)]. We have not found that both As(III) and As(V) stimulated the activity of DNA polymerase {beta} (pol {beta}), O{sup 6}methylguanine DNA methyltransferase (MGMT), and DNA ligase III. The activity of pol {beta} was increased up to 3.5-fold in the presence of 50 mM As (III), and 2-fold in the presence of 20 mM As(V). Inhibition of enzyme activity was only observed with concentrations of As(III) and As(V) higher than 100 mM. Terminal deoxynucleotidal transferase (TdT), an enzyme with homology to pol {beta}, is also stimulated 3-fold by 50 mM As(III). Unlike pol {beta} and TdT, MGMT was preferentially activated by millimolar As(V), rather than As(III). Similar concentrations of inorganic phosphate also increased the activity of MGMT. The activity of DNA ligase I was inhibited by 1 to 5 mM As(III). However, both DNA ligase I and DNA ligase III were significantly activated by As(V). In contrast to these results, human keratinocyte cells exhibit significant cytotoxicity when exposed to 10 {mu}M As(III) and 200 {mu}M AS(V). Cell survival was decreased by over 50% at these concentrations, as measured by neutral red uptake, LDH release, and MTT uptake. Interestingly, both As(III) and As(V) produced increased cell proliferation at submicromolar concentrations. These results suggest that arsenic compounds do not exert their toxic effects by direct inhibition of DNA repair enzymes, but by other mechanisms.

Su, Lin; Hu, Yu; Dunlop, B. [New York Univ. Medical Center, Tuxedo, NY (United States)] [and others

1997-10-01

166

Arsenic trioxide concentration determines the fate of Ewing's sarcoma family tumors and neuroblastoma cells in vitro.  

PubMed

Arsenic trioxide (As(2)O(3)) induces both the differentiation and apoptosis of acute promyelocytic leukemia cells in a concentration dependent manner. We assessed the effects of As(2)O(3) in CADO-ES Ewing's sarcoma (ES), JK-GMS peripheral primitive neuroectodermal tumor (PNET), and SH-SY5Y neuroblastoma cells, as they share common histogenetic backgrounds. As(2)O(3) at low concentrations (0.1-1 microM) induced SH-SY5Y differentiation, and whereas PNET cells acquired a slightly differentiated phenotype, change was minimal in ES cells. Extracellular signal-regulated kinase 2 (ERK2) was activated at low As(2)O(3) concentrations, and PD98059, an inhibitor of MEK-1, blocked SH-SY5Y cell differentiation by As(2)O(3). High concentrations (2-10 microM) of As(2)O(3) induced the apoptosis in all three cell lines, and this was accompanied by the activation of c-jun N-terminal kinase. The generation of H(2)O(2) and activation of caspase 3 were identified as critical components of As(2)O(3)-induced apoptosis in all of the above cell lines. Fibroblast growth factor 2 enhanced As(2)O(3)-induced apoptosis in JK-GMS cells. The overall effects of As(2)O(3) strongly suggest that it has therapeutic potential for the treatment of ES/PNET. PMID:16930595

Jung, Hyun Sook; Kim, Han-Seong; Lee, Min-Jae; Shin, Hee Young; Ahn, Hyo Seop; Ryu, Kyung-Ha; Seoh, Ju-Young; Kim, Chong Jai; Jang, Ja June

2006-09-01

167

Biochar addition to an arsenic contaminated soil increases arsenic concentrations in the pore water but reduces uptake to tomato plants (Solanum lycopersicum L.).  

PubMed

Arsenic (As) concentrations in soil, soil pore water and plant tissues were evaluated in a pot experiment following the transplantation of tomato (Solanum lycopersicum L.) plantlets to a heavily As contaminated mine soil (~6000 mg kg(-1) pseudo-total As) receiving an orchard prune residue biochar amendment, with and without NPK fertiliser. An in-vitro test was also performed to establish if tomato seeds were able to germinate in various proportions of biochar added to nutrient solution (MS). Biochar significantly increased arsenic concentrations in pore water (500 ?g L(-1)-2000 ?g L(-1)) whilst root and shoot concentrations were significantly reduced compared to the control without biochar. Fruit As concentrations were very low (<3 ?g kg(-1)), indicating minimal toxicity and transfer risk. Fertilisation was required to significantly increase plant biomass above the control after biochar addition whilst plants transplanted to biochar only were heavily stunted and chlorotic. Given that increasing the amount of biochar added to nutrient solution in-vitro reduced seed germination by up to 40%, a lack of balanced nutrient provision from biochar could be concluded. In summary, solubility and mobility of As were increased by biochar addition to this soil, but uptake to plant was reduced, and toxicity-transfer risk was negligible. Therefore leaching rather than food chain transfer appears the most probable immediate consequence of biochar addition to As contaminated soils. PMID:23583727

Beesley, Luke; Marmiroli, Marta; Pagano, Luca; Pigoni, Veronica; Fellet, Guido; Fresno, Teresa; Vamerali, Teofilo; Bandiera, Marianna; Marmiroli, Nelson

2013-06-01

168

AT1a receptor knockout in mice impairs urine concentration by reducing basal vasopressin levels and its receptor signaling proteins in the inner medulla  

Microsoft Academic Search

Angiotensin II plays an important role in the regulation of blood pressure, body salt and fluid balance, and urine concentration. Mice with deletion of the AT1a receptor develop polyuria and urine concentration defects. We studied the mechanisms of these urine concentration defects by treating wild-type and AT1a-knockout mice with arginine vasopressin (AVP) for 2 weeks, controlling their water intake, or

Xiao C Li; Yuan Shao; Jia L Zhuo

2009-01-01

169

The influence of arsenic speciation (As III & As V ) and concentration on the growth, uptake and translocation of arsenic in vegetable crops (silverbeet and amaranth): greenhouse study  

Microsoft Academic Search

We examined arsenic (As) uptake by vegetable crops (amaranth, Amaranthus\\u000a gangeticus, and silverbeet, Beta\\u000a vulgaris) as affected by As speciation (AsIII and AsV) and their concentrations in nutrient solution. Amaranth and silverbeet were grown in a nutrient solution containing four\\u000a levels of arsenate (AsV): 0, 1, 5, and 25 mg As\\/l and three levels of arsenite (AsIII): 0, 5, 10 mg As\\/l.

Farzana Rahman; Ravi Naidu

2009-01-01

170

Urothelial cell intracytoplasmic inclusions after treatment of promyelocytic leukemia with arsenic trioxide.  

PubMed

Intramitochondrial inclusions containing arsenite that occur within urothelial cells have been previously described in mice exposed to high concentrations of arsenic but not in rats. In epidemiology studies, similar urothelial cell inclusions have also been observed in the urine of humans exposed to high concentrations of arsenic in the drinking water; however, these inclusions were mistakenly identified as micronuclei. To further examine the urothelial cell inclusions that occur in inorganic arsenic-exposed humans, we evaluated two patients with a history of acute promyelocytic leukemia treated for disease relapse with a combination of all-trans retinoic acid and arsenic trioxide. Posttreatment examination of the patients' urine cytology specimens by light and electron microscopy demonstrated cytoplasmic inclusions in exfoliated superficial urothelial cells similar to those seen in mice. The inclusions were present in decreasing quantities at 3 and 7 months after completion of treatment. No comparable inclusions were detected in exfoliated urothelial cells in urine from six individuals not treated with arsenic trioxide. Based on the results of the examination by light and electron microscopy, we have determined that urothelial cell inclusions in the urine of humans previously identified as micronuclei are instead intracytoplasmic inclusions similar to those found in arsenic-treated mice. PMID:23744094

Wedel, Whitney R; Muirhead, David E; Arnold, Lora L; Dodmane, Puttappa R; Lele, Subodh M; Maness-Harris, Lori; Hoyt, Rose; Cohen, Samuel M

2013-08-01

171

Assessment of in vivo bioaccessibility of arsenic in dietary rice by a mass balance approach.  

PubMed

A pilot dietary experiment was conducted over 10 days to evaluate whether a simple yet often underutilized approach of constructing mass balance of arsenic metabolites can be used to assess in vivo bioaccessibility of arsenic in cooked rice. Two volunteers were involved in this study. The quantity of drinking water, food and urine samples, together with arsenic concentration and speciation of these samples was monitored to construct a mass balance of arsenic intake and excretion. In the first five days, the two volunteers on a wheat diet had an average arsenic daily intake of 15.4+/-2.6microg and 9.6+/-0.7microg, respectively. In the next five days, these volunteers switched to a rice diet, increasing the average arsenic daily intake to 36.4+/-2.8microg and 34.1+/-7.7microg, respectively. Daily excretion of urinary arsenic, mostly as dimethylarsenic acid (DMA), doubled from 9.8+/-0.3microg to 21.0+/-3.0microg, and from 6.5+/-0.8microg to 11.6+/-4.5microg, respectively. The percentage of ingested arsenic excreted in urine remained constant at approximately 58% for one volunteer before and after the rice diet, and was approximately 69% for another. Mass balance established during a controlled dietary experiment over 10 days is shown to be a useful approach to evaluate in vivo bioaccessibility and metabolism of arsenic uptake from diet and is applicable to study with more subjects. PMID:20071009

He, Yi; Zheng, Yan

2010-02-15

172

Detailed arsenic concentration profiles at Si/SiO2 interfaces  

SciTech Connect

The pile-up of arsenic at the Si/SiO2 interface after As implantation and annealing was investigated by high resolution Z-contrast imaging, electron energy-loss spectroscopy EELS, grazing incidence x-ray fluorescence spectroscopy GI-XRF, secondary ion mass spectrometry, x-ray photoelectron spectroscopy, Rutherford backscattering spectrometry, as well as Hall mobility and four-point probe resistivity measurements. After properly taking into account their respective artifacts, the results of all methods are compatible with each other, with EELS and GI-XRF combined with etching providing similar spatial resolution on the nanometer scale for the dopant profile. The sheet concentration of the piled-up As at the interface was found to be 11015 cm 2 for an implanted dose of 11016 cm 2 with a maximum concentration of 10 at. %. The strain observed in the Z-contrast images also suggests a significant concentration of local distortions within 3 nm from the interface, which, however, do not seem to involve intrinsic point defects. 2008 American Institute of Physics.

Pei, Lirong [ORNL

2008-01-01

173

COMPLEMENTARY APPROACHES TO THE DETERMINATION OF ARSENIC SPECIES RELEVANT TO CONCENTRATED ANIMAL FEEDING OPERATIONS  

EPA Science Inventory

Ion-exchange chromatography is the most often used analytical approach for arsenic speciation, due to the weak-acid nature of several of its species. However, no single technique can determine all potentially occurring arsenic species, especially in complex e...

174

New insights into urea and glucose handling by the kidney, and the urine concentrating mechanism.  

PubMed

The mechanism by which urine is concentrated in the mammalian kidney remains incompletely understood. Urea is the dominant urinary osmole in most mammals and may be concentrated a 100-fold above its plasma level in humans and even more in rodents. Several facilitated urea transporters have been cloned. The phenotypes of mice with deletion of the transporters expressed in the kidney have challenged two previously well-accepted paradigms regarding urea and sodium handling in the renal medulla but have provided no alternative explanation for the accumulation of solutes that occurs in the inner medulla. In this review, we present evidence supporting the existence of an active urea secretion in the pars recta of the proximal tubule and explain how it changes our views regarding intrarenal urea handling and UT-A2 function. The transporter responsible for this secretion could be SGLT1, a sodium-glucose cotransporter that also transports urea. Glucagon may have a role in the regulation of this secretion. Further, we describe a possible transfer of osmotic energy from the outer to the inner medulla via an intrarenal Cori cycle converting glucose to lactate and back. Finally, we propose that an active urea transporter, expressed in the urothelium, may continuously reclaim urea that diffuses out of the ureter and bladder. These hypotheses are all based on published findings. They may not all be confirmed later on, but we hope they will stimulate further research in new directions. PMID:22456603

Bankir, Lise; Yang, Baoxue

2012-06-01

175

Concentration of marijuana metabolites in the urine after ingestion of hemp seed tea.  

PubMed

To determine whether ingestion of hemp seed tea could result in positive urine drug screens for cannabinoids, volunteers were recruited to donate urine after consuming hemp seed or placebo tea. Among the 22 participants, 10 ingested 12 ounces of hemp seed tea, 10 ingested 24 ounces, and 2 ingested 12 ounces of placebo tea. Urine cannabinoid specimens were obtained at baseline and at 4, 8, and 24 hours after ingestion. A total of 10 specimens had trace quantities of cannabinoids detected in 7 subjects on gas chromatography/mass spectrometry testing, all below the Department of Transportation cutoff level of 15 ng/mL. These results demonstrate that under the conditions of this study, hemp seed tea consumption can result in detectable urine cannabinoids but would not trigger a positive EMIT or gas chromatography/mass spectrometry urine drug test for cannabinoids. PMID:10390703

Steinagle, G C; Upfal, M

1999-06-01

176

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

177

Naturally dissolved arsenic concentrations in the Alpine/Mediterranean Var River watershed (France).  

PubMed

A detailed study on arsenic (As) in rocks and water from the Var River watershed was undertaken aiming at identifying (i) the origin and the distribution of As in this typical Alpine/Mediterranean basin, and (ii) As input into the Mediterranean Sea. Dissolved As concentrations in the Var River range from 0.1 to 4.5 ?g?L(-1), due to high hydrological variability and the draining through different geological formations. In the upper part of the Var drainage basin, in the Tinée and the Vésubie valleys, high levels of dissolved As concentrations occur (up to 263 ?g?L(-1)). The two main sources of As in rocks are the Hercynian metamorphic rocks and the Permian argilites. Highly heterogeneous distribution of As in waters draining through metamorphic rocks is probably related to ore deposits containing arsenopyrite. As, U, W and Mo concentrations in water and rocks correspond to the formation of As-rich ore deposits around Argentera granite by hydrothermal fluids deposited at the end of the Hercynian chain formation, which occurred about 300 My ago. In 2009, weekly monitoring was performed on the Var River (15 km upstream of the mouth), highlighting an average dissolved As concentration (<0.45 ?m) of 2.7 ± 0.9 ?g?L(-1), which is significantly higher than the world-average baseline for river water (0.83 ?g?L(-1)). Taking the average annual discharge (49.4 m(3)?s(-1)) into account and the As levels in the dissolved phase and in deposits of the Var River, dissolved As input into the Mediterranean Sea would be 4. 2± 1.4 tons?year(-1) which represents 59% of the total As flux. This study also reveals a probable non-conservative As behaviour, i.e., possible transfer between aqueous and solid phases, during the mixing of the Var River with a tributary. PMID:24388820

Barats, Aurélie; Féraud, Gilbert; Potot, Cécile; Philippini, Violaine; Travi, Yves; Durrieu, Gaël; Dubar, Michel; Simler, Roland

2014-03-01

178

Morphine to codeine concentration ratio in blood and urine as a marker of illicit heroin use in forensic autopsy samples.  

PubMed

A morphine to codeine ratio greater than unity (M/C>1) has been suggested as an indicator of heroin use in living individuals. The aim of this study was to examine the morphine to codeine ratio in a large population (N=2438) of forensically examined autopsy cases positive for 6-monoacetylmorphine (6-MAM) and/or morphine in blood and/or urine. Blood and urine concentrations of 6-MAM, morphine and codeine were examined using GC-MS and LC-MS/MS methods. In 6-MAM positive samples, the M/C ratio was greater than unity in 98% (N=917) of the blood samples and 96% (N=665) of the urine samples. Stratification of 6-MAM negative cases by M/C above or below unity revealed similarities in morphine and codeine concentrations in cases where M/C>1 and 6-MAM positive cases. Median blood and urine morphine concentrations were 8-10 times greater than codeine for both groups. Similarly to 6-MAM positive cases, 25-44 year-old men prevailed in the M/C>1 group. In comparison to cases where M/C ? 1, the M/C ratio was a hundred times higher in both 6-MAM positive and M/C>1 cases. The range of morphine concentration between the lowest and the highest quintile of codeine in M/C>1 cases was similar to that in 6-MAM positive cases. This range was much higher than for M/C ? 1 cases. Moreover, linear regression analyses, adjusted for age and gender, revealed a strong positive association between morphine and codeine in 6-MAM positive and M/C>1 cases. The M/C ratio appeared to be a good marker of heroin use in post-mortem cases. Both blood and urine M/C>1 can be used to separate heroin users from other cases positive for morphine and codeine. PMID:22137531

Konstantinova, Svetlana V; Normann, Per T; Arnestad, Marianne; Karinen, Ritva; Christophersen, Asbjřrg S; Mřrland, Jřrg

2012-04-10

179

Digital spatial data for predicted nitrate and arsenic concentrations in basin-fill aquifers of the Southwest Principal Aquifers study area  

USGS Publications Warehouse

This product "Digital spatial data for predicted nitrate and arsenic concentrations in basin-fill aquifers of the Southwest Principal Aquifers study area" is a 1:250,000-scale vector spatial dataset developed as part of a regional Southwest Principal Aquifers (SWPA) study (Anning and others, 2012). The study examined the vulnerability of basin-fill aquifers in the southwestern United States to nitrate contamination and arsenic enrichment. Statistical models were developed by using the random forest classifier algorithm to predict concentrations of nitrate and arsenic across a model grid that represents local- and basin-scale measures of source, aquifer susceptibility, and geochemical conditions.

McKinney, Tim S.; Anning, David W.

2012-01-01

180

Airborne arsenic exposure and excretion of methylated arsenic compounds.  

PubMed Central

First void urine samples were collected from copper smelter workers exposed to inorganic arsenic and from unexposed controls. Arsenic compounds (As (III), As (V), methylarsonic acid and dimethylarsinic acid) in these samples were analyzed by selective volatilization as arsines with determination of arsenic by plasma excitation emission spectrometry. On the day preceding the urine sample collection a breathing zone measurement was made of respirable arsenic particulates for each subject. It was found that all of the subjects, including the controls excreted arsenic primarily as methylated species. Approximately 50% of the total arsenic was excreted as dimethylarsinic acid and 20% as methylarsonic acid. Slight differences in the proportion of various arsenic compounds were observed with varying levels of inorganic arsenic exposure. Amounts of arsenic species were all closely correlated with each other and with exposure. Irrespirable particulate exposures were measured on a subset of high exposure workers. Irrespirable arsenic was found to be more closely correlated with excretion of arsenic compounds than was respirable arsenic.

Smith, T J; Crecelius, E A; Reading, J C

1977-01-01

181

Factors affecting paddy soil arsenic concentration in Bangladesh: prediction and uncertainty of geostatistical risk mapping.  

PubMed

Knowledge of the spatial correlation of soil arsenic (As) concentrations with environmental variables is needed to assess the nature and extent of the risk of As contamination from irrigation water in Bangladesh. We analyzed 263 paired groundwater and paddy soil samples covering highland (HL) and medium highland-1 (MHL-1) land types for geostatistical mapping of soil As and delineation of As contaminated areas in Tala Upazilla, Satkhira district. We also collected 74 non-rice soil samples to assess the baseline concentration of soil As for this area. The mean soil As concentrations (mg/kg) for different land types under rice and non-rice crops were: rice-MHL-1 (21.2)>rice-HL (14.1)>non-rice-MHL-1 (11.9)>non-rice-HL (7.2). Multiple regression analyses showed that irrigation water As, Fe, land elevation and years of tubewell operation are the important factors affecting the concentrations of As in HL paddy soils. Only years of tubewell operation affected As concentration in the MHL-1 paddy soils. Quantitatively similar increases in soil As above the estimated baseline-As concentration were observed for rice soils on HL and MHL-1 after 6-8 years of groundwater irrigation, implying strong retention of As added in irrigation water in both land types. Application of single geostatistical methods with secondary variables such as regression kriging (RK) and ordinary co-kriging (OCK) gave little improvement in prediction of soil As over ordinary kriging (OK). Comparing single prediction methods, kriging within strata (KWS), the combination of RK for HL and OCK for MHL-1, gave more accurate soil As predictions and showed the lowest misclassification of declaring a location "contaminated" with respect to 14.8 mg As/kg, the highest value obtained for the baseline soil As concentration. Prediction of soil As buildup over time indicated that 75% or the soils cropped to rice would contain at least 30 mg/L As by the year 2020. PMID:22055452

Ahmed, Zia U; Panaullah, Golam M; DeGloria, Stephen D; Duxbury, John M

2011-12-15

182

Arsenic metabolism in seaweed-eating sheep from Northern Scotland.  

PubMed

Cation exchange and anion exchange liquid chromatography were coupled to an ICP-MS and optimised for the separation of 13 different arsenic species in body fluids (arsenite, arsenate, dimethylarsinic acid (DMAA), monomethylarsonic acid (MMAA), trimethylarsine oxide (TMAO), tetramethylarsonium ion (TMA), arsenobetaine (AsB), arsenocholine (AsC), dimethylarsinoyl ethanol (DMAE) and four common dimethylarsinoylribosides (arsenosugars). The arsenic species were determined in seaweed extracts and in the urine and blood serum of seaweed-eating sheep from Northern Scotland. The sheep eat 2-4 kg of seaweed daily which is washed ashore on the most northern Island of Orkney. The urine, blood and wool of 20 North Ronaldsay sheep and kidney, liver and muscle from 11 sheep were sampled and analysed for their arsenic species. In addition five Dorset Finn sheep, which lived entirely on grass, were used as a control group. The sheep have a body burden of approximately 45-90 mg arsenic daily. Since the metabolism of arsenic species varies with the arsenite and arsenate being the most toxic, and organoarsenic compounds such as arsenobetaine the least toxic compounds, the determination of the arsenic species in the diet and their body fluids are important. The major arsenic species in their diet are arsenoribosides. The major metabolite excreted into urine and blood is DMAA (95 +/- 4.1%) with minor amounts of MMAA, riboside X, TMA and an unidentified species. The occurrence of MMAA is assumed to be a precursor of the exposure to inorganic arsenic, since demethylation of dimethylated or trimethylated organoarsenic compounds is not known (max. MMAA concentration 259 microg/L). The concentrations in the urine (3179 +/- 2667 microg/L) and blood (44 +/- 19 microg/kg) are at least two orders of magnitude higher than the level of arsenic in the urine of the control sheep or literature levels of blood for the unexposed sheep. The tissue samples (liver: 292 +/- 99 microg/kg, kidney: 565 +/- 193 microg/kg, muscle: 680 +/- 224 microg/kg) and wool samples (10470 +/- 5690 microg/kg) show elevated levels which are also 100 times higher than the levels for the unexposed sheep. PMID:11220824

Feldmann, J; John, K; Pengprecha, P

2000-09-01

183

Associations between land cover categories, soil concentrations of arsenic, lead and barium, and population race/ethnicity and socioeconomic status.  

PubMed

The potential of using land cover/use categories as a proxy for soil metal concentrations was examined by measuring associations between Anderson land cover category percentages and soil concentrations of As, Pb, and Ba in ten sampling areas. Land cover category and metal associations with ethnicity and socioeconomic status at the United States Census 2000 block and block group levels also were investigated. Arsenic and Pb were highest in urban locations; Ba was a function of geology. Consistent associations were observed between urban/built up land cover, and Pb and poverty. Land cover can be used as proxy for metal concentrations, although associations are metal-dependent. PMID:24914533

Davis, Harley T; Aelion, C Marjorie; Lawson, Andrew B; Cai, Bo; McDermott, Suzanne

2014-08-15

184

Chronic Arsenic Exposure in Nanomolar Concentrations Compromises Wound Response and Intercellular Signaling in Airway Epithelial Cells  

PubMed Central

Paracrine ATP signaling in the lung epithelium participates in a variety of innate immune functions, including mucociliary clearance, bactericide production, and as an initiating signal in wound repair. We evaluated the effects of chronic low-dose arsenic relevant to U.S. drinking water standards (i.e., 10 ppb [130nM]) on airway epithelial cells. Immortalized human bronchial epithelial cells (16HBE14o-) were exposed to 0, 130, or 330nM arsenic (as Na-arsenite) for 4–5 weeks and examined for wound repair efficiency and ATP-mediated Ca2+ signaling. We found that chronic arsenic exposure at these low doses slows wound repair and reduces ATP-mediated Ca2+ signaling. We further show that arsenic compromises ATP-mediated Ca2+ signaling by altering both Ca2+ release from intracellular stores (via metabotropic P2Y receptors) and Ca2+ influx mechanisms (via ionotropic P2X receptors). To better model the effects of arsenic on ATP-mediated Ca2+ signaling under conditions of natural exposure, we cultured tracheal epithelial cells obtained from mice exposed to control or 50 ppb Na-arsenite supplemented drinking water for 4 weeks. Tracheal epithelial cells from arsenic-exposed mice displayed reduced ATP-mediated Ca2+ signaling dynamics similar to our in vitro chronic exposure. Our findings demonstrate that chronic arsenic exposure at levels that are commonly found in drinking water (i.e., 10–50 ppb) alters cellular mechanisms critical to airway innate immunity.

Boitano, Scott

2013-01-01

185

Comparison of urine toxic metals concentrations in athletes and in sedentary subjects living in the same area of Extremadura (Spain).  

PubMed

Cadmium (Cd), tungsten (W), tellurium (Te), beryllium (Be), and lead (Pb), are non-essential metals pervasive in the human environment. Studies on athletes during training periods compared to non-training control subjects, indicate increased loss of minerals through sweat and urine. The aim of this study was to compare the level of these trace elements, determined by inductively coupled plasma mass spectrometry (ICP-MS) in urine samples, between athletes and age-matched sedentary subjects living in the same geographical area, although anthropometric and cardiovascular measurements showed that athletes have significantly (P ? 0.001) lower BMI, body fat and heart rate, whereas the muscle and bone percentage was significantly (P ? 0.001) higher than in sedentary subjects. The validity of the methodology was checked by the biological certified reference material. Trace element analysis concentrations, expressed in ?g/mg creatinine, of five toxic elements in urine from athletes (n = 21) versus sedentary subjects, (n = 26) were as follows: Cd (0.123 ± 0.075 vs. 0.069 ± 0.041, P ? 0.05); W (0.082 ± 0.053 vs. < limit of detection); Te (0.244 ± 0.193 vs. 0.066 ± 0.045, P ? 0.001), Be (0.536 ± 0.244 vs. 0.066 ± 0.035, P ? 0.001); Pb (0.938 ± 0.664 vs. 2.162 ± 1.444 P ? 0.001). With the exception of Pb, urine toxic metal concentrations from athletes were higher than from sedentary subjects. This fact suggests that physical activity counteracts, at least in part, the cumulative effect of toxic environment by increasing the urine excretion of toxic metals in trained people. PMID:22179857

Llerena, F; Maynar, M; Barrientos, G; Palomo, R; Robles, M C; Caballero, M J

2012-08-01

186

Mathematical modeling of the effects of glutathione on arsenic methylation  

PubMed Central

Background Arsenic is a major environmental toxin that is detoxified in the liver by biochemical mechanisms that are still under study. In the traditional metabolic pathway, arsenic undergoes two methylation reactions, each followed by a reduction, after which it is exported and released in the urine. Recent experiments show that glutathione plays an important role in arsenic detoxification and an alternative biochemical pathway has been proposed in which arsenic is first conjugated by glutathione after which the conjugates are methylated. In addition, in rats arsenic-glutathione conjugates can be exported into the plasma and removed by the liver in the bile. Methods We have developed a mathematical model for arsenic biochemistry that includes three mechanisms by which glutathione affects arsenic methylation: glutathione increases the speed of the reduction steps; glutathione affects the activity of arsenic methyltranferase; glutathione sequesters inorganic arsenic and its methylated downstream products. The model is based as much as possible on the known biochemistry of arsenic methylation derived from cellular and experimental studies. Results We show that the model predicts and helps explain recent experimental data on the effects of glutathione on arsenic methylation. We explain why the experimental data imply that monomethyl arsonic acid inhibits the second methylation step. The model predicts time course data from recent experimental studies. We explain why increasing glutathione when it is low increases arsenic methylation and that at very high concentrations increasing glutathione decreases methylation. We explain why the possible temporal variation of the glutathione concentration affects the interpretation of experimental studies that last hours. Conclusions The mathematical model aids in the interpretation of data from recent experimental studies and shows that the Challenger pathway of arsenic methylation, supplemented by the glutathione effects described above, is sufficient to understand and predict recent experimental data. More experimental studies are needed to explicate the detailed mechanisms of action of glutathione on arsenic methylation. Recent experimental work on the effects of glutathione on arsenic methylation and our modeling study suggest that supplements that increase hepatic glutathione production should be considered as strategies to reduce adverse health effects in affected populations.

2014-01-01

187

The concentrations of arsenic and other toxic elements in Bangladesh's drinking water.  

PubMed Central

For drinking water, the people of Bangladesh used to rely on surface water, which was often contaminated with bacteria causing diarrhea, cholera, typhoid, and other life-threatening diseases. To reduce the incidences of these diseases, millions of tubewells were installed in Bangladesh since independence in 1971. This recent transition from surface water to groundwater has significantly reduced deaths from waterborne pathogens; however, new evidence suggests disease and death from arsenic (As) and other toxic elements in groundwater are affecting large areas of Bangladesh. In this evaluation, the areal and vertical distribution of As and 29 other inorganic chemicals in groundwater were determined throughout Bangladesh. This study of 30 analytes per sample and 112 samples suggests that the most significant health risk from drinking Bangladesh's tubewell water is chronic As poisoning. The As concentration ranged from < 0.0007 to 0.64 mg/L, with 48% of samples above the 0.01 mg/L World Health Organization drinking water guideline. Furthermore, this study reveals unsafe levels of manganese (Mn), lead (Pb), nickel (Ni), and chromium (Cr). Our survey also suggests that groundwater with unsafe levels of As, Mn, Pb, Ni, and Cr may extend beyond Bangladesh's border into the four adjacent and densely populated states in India. In addition to the health risks from individual toxins, possible multimetal synergistic and inhibitory effects are discussed. Antimony was detected in 98% of the samples from this study and magnifies the toxic effects of As. In contrast, Se and Zn were below our detection limits in large parts of Bangladesh and prevent the toxic effects of As.

Frisbie, Seth H; Ortega, Richard; Maynard, Donald M; Sarkar, Bibudhendra

2002-01-01

188

Arsenic and heavy metal concentrations in surface soils and vegetables of Feni district in Bangladesh.  

PubMed

An investigation of various heavy metals including the arsenic (As) poisoning in soils and vegetables in five upazillas under Feni district of Bangladesh was performed by neutron activation technique using the neutron irradiation facilities of TRIGA MARK II research reactor at Bangladesh Atomic Energy Research Establishment (BAERE), Savar, Dhaka. A total of 30 samples (15 surface soils and 15 foodstuffs) were studied in five Upazillas namely as, Sonagazi, Dagan Bhuiya, Feni Sadar, Fulgazi and Parsuram of Feni district taking three samples of each kind from each upazilla. Samples of each kind together with the standard reference material (SRM) were irradiated in the same neutron flux and the gamma-rays of nuclides from the irradiated samples were assessed and screened for As, Br, U, Th, Cr, Sc, Fe, Zn and Co in soils and As, Br, Na, K, Cr, Sc, Fe, Zn and Co in vegetables (i.e; eddoe, taro, green papaya, plantain, potato, callaloo, bottle ground and carambola). The measurement of gamma-rays was carried out by means of a calibrated high resolution HPGe detector. The concentration of product nuclides containing in the irradiated samples was determined from the peak count-rates of prominent gamma-lines for the corresponding nuclides. Among all contaminants, only As, Zn and Cr for both samples were focused because of their higher values compared with the local as well as the world typical values. The present results revealed that the mean levels of As in Parsuram, Feni Sadar and Pulgazi upazillas are higher than the world typical value of 2 mg/kg. The mean values of Zn and Cr for all upazillas are higher than the world typical values 32 and 27.9 mg/kg, respectively. For the case of vegetables, the mean concentration of As is found only in Eddoe (5.33 ppm) and Taro (1.46 ppm) collected from Sonagazi and Feni Sadar upazilla; which are higher than the values in Samta (0.1 ppm for eddoe and 0.44 ppm for taro) under Jessore district of Bangladesh. The mean concentrations of Zn and Cr in all kinds of vegetables are higher compared with the existing local values as well as the world typical values. The mean estimated daily dietary intake of As, Zn and Cr from vegetables are found to be 0.105, 12.47 and 3.53 mg respectively, which are higher than the recommended values of some countries. The consumption of toxic metals in vegetables is a risk for public health in the studied area. PMID:18165906

Karim, R A; Hossain, S M; Miah, M M H; Nehar, K; Mubin, M S H

2008-10-01

189

Effect of sodium chloride intake on urine volume, urinary urea excretion, and milk urea concentration in lactating dairy cattle.  

PubMed

Milk urea nitrogen (MUN; mg of N/dL) has been shown to be related to excretion of urinary urea N (UUN; g of N/d) and total excretion of urinary N (UN; g of N/d) in dairy cows. In the present experiment, it was hypothesized that MUN and the relationship between MUN and UUN or UN is affected by urine volume as a result of dietary sodium chloride intake. Twelve lactating Holstein-Friesian dairy cows (mean ± SD: milk production 28.1±3.23 kg/d and 190±41 d in milk), of which 4 were fitted with catheters in the urine bladder and jugular vein, were randomly assigned to 4 dietary levels of sodium chloride (3, 9, 14, and 19 g of Na/kg of DM) according to a triple 4×4 Latin square design. Cows were fed at 95% of ad libitum intake, excluding salt addition. Milk was analyzed for MUN and protein content; urine was analyzed for total N, urea, and creatinine content; feces were analyzed for total N and DM content; and blood plasma was analyzed for urea and creatinine content. Creatinine clearance rate (CCR; L/min) and renal urea reabsorption ratio were estimated based on plasma concentrations of urea and creatinine, and total excretion of urea and creatinine in urine. Intake of DM and N, milk production, and milk protein content were (mean ± SD), on average, 21.4±1.24 kg/d, 522±32.0 g/d, 25.4±2.53 kg/d, and 3.64±0.186%, respectively. A linear relationship was found between Na intake and urine production [urine (kg/d; mean ± SE)=7.5±4.33+0.136±0.0143 × Na intake (g/d)] and between Na intake and MUN [MUN (mg/dL; mean ± SE)=13.5±0.35-0.0068±0.00104 × Na intake (g/d)]. Despite the decrease in MUN with increased Na intake, UN excretion increased linearly with Na intake. Excretion of UUN was not affected by dietary Na content. A linear plateau relationship was observed between CCR and renal urea reabsorption. An increase in CCR coincided with an increase in calculated renal urea reabsorption until a CCR breakpoint value (mean ± SD) of 1.56±0.063 L/min was reached. We conclude that Na intake is negatively related to MUN, whereas UUN is not affected. Variation in mineral intake levels that affect urine volume should, therefore, be taken into account when using MUN as an indicator of UUN in dairy cattle. PMID:23063155

Spek, J W; Bannink, A; Gort, G; Hendriks, W H; Dijkstra, J

2012-12-01

190

Association between In Utero arsenic exposure, placental gene expression, and infant birth weight: a US birth cohort study  

PubMed Central

Background Epidemiologic studies and animal models suggest that in utero arsenic exposure affects fetal health, with a negative association between maternal arsenic ingestion and infant birth weight often observed. However, the molecular mechanisms for this association remain elusive. In the present study, we aimed to increase our understanding of the impact of low-dose arsenic exposure on fetal health by identifying possible arsenic-associated fetal tissue biomarkers in a cohort of pregnant women exposed to arsenic at low levels. Methods Arsenic concentrations were determined from the urine samples of a cohort of 133 pregnant women from New Hampshire. Placental tissue samples collected from enrollees were homogenized and profiled for gene expression across a panel of candidate genes, including known arsenic regulated targets and genes involved in arsenic transport, metabolism, or disease susceptibility. Multivariable adjusted linear regression models were used to examine the relationship of candidate gene expression with arsenic exposure or with birth weight of the baby. Results Placental expression of the arsenic transporter AQP9 was positively associated with maternal urinary arsenic levels during pregnancy (coefficient estimate: 0.25; 95% confidence interval: 0.05 – 0.45). Placental expression of AQP9 related to expression of the phospholipase ENPP2 which was positively associated with infant birth weight (coefficient estimate: 0.28; 95% CI: 0.09 – 0.47). A structural equation model indicated that these genes may mediate arsenic’s effect on infant birth weight (coefficient estimate: -0.009; 95% confidence interval: -0.032 – -0.001; 10,000 replications for bootstrapping). Conclusions We identified the expression of AQP9 as a potential fetal biomarker for arsenic exposure. Further, we identified a positive association between the placental expression of phospholipase ENPP2 and infant birth weight. These findings suggest a path by which arsenic may affect birth outcomes.

2013-01-01

191

Airborne arsenic and urinary excretion of metabolites of inorganic arsenic among smelter workers  

Microsoft Academic Search

Summary The relationship between airborne concentrations of arsenic and the urinary excretion of inorganic arsenic metabolites (inorganic arsenic + methylarsonic acid + dimethylarsinic acid) have been studied among smelter workers exposed to arsenic trioxide. The urinary concentrations of arsenic metabolites were found to increase steadily during the first day of the working week (after 2–3 d off from work), whereafter

Marie Vahter; Lars Friberg; Barbro Rahnster; Ĺke Nygren; Peter Nolinder

1986-01-01

192

Blood and urine responses to ingesting fluids of various salt and glucose concentrations. [to combat orthostatic intolerance  

NASA Technical Reports Server (NTRS)

To compensate for the reduced blood and fluid volumes that develop during weightlessness, the Space Shuttle crewmembers consume salt tablets and water equivalent to 1 l of normal saline, about 2 hrs before landing. This paper compares the effects on blood, urine, and cardiovascular variables of the ingestion of 1 l of normal (0.9 percent) saline with the effects of distilled water, 1 percent glucose, 0.74 percent saline with 1 percent glucose, 0.9 percent saline with 1 percent glucose, and 1.07 percent saline. It was found that the expansion of plasma volume and the concentration of urine were greater 4 hrs after ingestion of 1.07 percent saline solution than after ingestion of normal saline and that the solutions containig glucose did not enhance any variables as compared with normal saline.

Frey, Mary A.; Riddle, Jeanne; Charles, John B.; Bungo, Michael W.

1991-01-01

193

Arsenic groundwater contamination in Middle Ganga Plain, Bihar, India: a future danger?  

PubMed Central

The pandemic of arsenic poisoning due to contaminated groundwater in West Bengal, India, and all of Bangladesh has been thought to be limited to the Ganges Delta (the Lower Ganga Plain), despite early survey reports of arsenic contamination in groundwater in the Union Territory of Chandigarh and its surroundings in the northwestern Upper Ganga Plain and recent findings in the Terai area of Nepal. Anecdotal reports of arsenical skin lesions in villagers led us to evaluate arsenic exposure and sequelae in the Semria Ojha Patti village in the Middle Ganga Plain, Bihar, where tube wells replaced dug wells about 20 years ago. Analyses of the arsenic content of 206 tube wells (95% of the total) showed that 56.8% exceeded arsenic concentrations of 50 micro g/L, with 19.9% > 300 micro g/L, the concentration predicting overt arsenical skin lesions. On medical examination of a self-selected sample of 550 (390 adults and 160 children), 13% of the adults and 6.3% of the children had typical skin lesions, an unusually high involvement for children, except in extreme exposures combined with malnutrition. The urine, hair, and nail concentrations of arsenic correlated significantly (r = 0.72-0.77) with drinking water arsenic concentrations up to 1,654 micro g/L. On neurologic examination, arsenic-typical neuropathy was diagnosed in 63% of the adults, a prevalence previously seen only in severe, subacute exposures. We also observed an apparent increase in fetal loss and premature delivery in the women with the highest concentrations of arsenic in their drinking water. The possibility of contaminated groundwater at other sites in the Middle and Upper Ganga Plain merits investigation.

Chakraborti, Dipankar; Mukherjee, Subhash C; Pati, Shyamapada; Sengupta, Mrinal K; Rahman, Mohammad M; Chowdhury, Uttam K; Lodh, Dilip; Chanda, Chitta R; Chakraborti, Anil K; Basu, Gautam K

2003-01-01

194

Arsenic removal during precipitative softening  

SciTech Connect

Because utilities with hard waters tend to have higher concentrations of arsenic, removal of arsenic via precipitative softening processes was investigated in the context of the more stringent proposed arsenic regulation. Arsenic removal can be facilitated by a variety of solids formed during softening including CaCO{sub 3}, Mg(OH){sub 2}, Mn(OH){sub 2}, and Fe(OH){sub 3}. The extent of As(V) removal is decreased in the presence of orthophosphate and carbonate. As(III) removal is much lower than As(V) removal. At typical solids concentrations, arsenic removal followed a linear isotherm for CaCO{sub 3}, Mg(OH){sub 2}, and Fe(OH){sub 3}, with constant percentage arsenic removal regardless of initial arsenic concentrations. However, for Mn(OH){sub 2} solids arsenic removal was sensitive to arsenic concentrations. A framework for predicting arsenate removal when multiple solids form during softening is presented.

McNeill, L.S.; Edwards, M. [Univ. of Colorado, Boulder, CO (United States)

1997-05-01

195

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

PubMed

Lead in blood is a major concept in biomonitoring of exposure but investigations of its alternatives are scarce. The aim of the study was to describe different lead biomarkers' variances, day-to-day and between individuals, estimating their fraction of the total variance. Repeated sampling of whole blood, plasma and urine were conducted for 48 lead-exposed men and 20 individuals under normal environmental lead exposure, in total 603 measurements. For lead workers, the fraction of the total variance attributed to differences between individuals was 91% for whole-blood lead (geometric mean 227??g/l; geometric standard deviation (GSD): 1.55??g/l); plasma 78% (0.57??g/l; GSD: 1.84??g/l); density-adjusted urine 82%; and unadjusted urine 75% (23.7??g/l; GSD: 2.48??g/l). For the individuals under normal lead exposure, the corresponding fractions were 95% of the total variance for whole blood (20.7??g/l; GSD: 8.6??g/l), 15% for plasma (0.09??g/l; GSD: 0.04??g/l), 87% for creatinine-adjusted urine and 34% for unadjusted (10.8??g/l; GSD: 6.7??g/l). Lead concentration in whole blood is the biomarker with the best ability to discriminate between individuals with different mean concentration. Urinary and plasma lead also performed acceptably in lead workers, but at low exposures plasma lead was too imprecise. Urinary adjustments appear not to increase the between-individual fraction of the total variance among lead workers but among those with normal lead exposure. PMID:23443239

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

2014-01-01

196

Questions and Answers: Apple Juice and Arsenic  

MedlinePLUS

... products, including fruit juices and juice concentrates. * Some scientific studies have shown that two forms of organic arsenic ... type of arsenic considered harmful to humans. Some scientific studies have shown that two forms of organic arsenic ...

197

High arsenic concentrations and enriched sulfur and oxygen isotopes in a fractured-bedrock ground-water system  

USGS Publications Warehouse

Ground water with high arsenic concentrations (up to 26.6????mol L- 1) has sulfate enriched in 34S and 18O in the fractured-bedrock, ground-water system of the Kelly's Cove watershed, Northport, Maine, USA. The ranges of sulfur and oxygen isotope values in aqueous sulfate, ??34S[SO4] and ??18O[SO4], at the Kelly's Cove watershed are + 3.4 to + 4.9??? and - 2.0 to + 6.7???, respectively. These isotope values are strikingly similar to those of the Goose River, Maine watershed which has ??34S[SO4] and ??18O[SO4] ranges of + 3.7 to + 4.6 ??? and - 2.6 to + 7.5???, respectively. In both systems, high arsenic concentrations occur with high ??34S[SO4] and ??18O[SO4] values, yet redox conditions and underlying rock types are quite different. The isotope values of sulfide minerals, ??34S[min], from four bedrock cores vary over short distances and range from - 5.1 to + 7.5???. The ??34S[SO4] values are controlled by the ??34S[min] values with minor input of atmospheric SO4. The much narrower range in ??34S[SO4] values than ??34S[min] values is probably due to sufficient ground-water mixing at a scale greater than the ??34S[min] variability. The ??34S[SO4] values are about 2??? higher than the average ??34S[min] value and fall within the range of ??34S[min] values, indicating only minor fractionation due to bacterial reduction of SO4. The highest ??18O[SO4] values were measured in the downgradient, confined, arsenic-rich ground water. High ??18O[SO4] values there cannot be due to aeration by atmospheric oxygen, but may arise from reoxidation of reduced SO4 products. The enrichment factors of ??18O in SO4 compared to H2O, + 7.2 to + 15.5???, in the Kelly's Cove ground water and the negligible 34S enrichment is very similar to those derived from experimental data of anaerobic sulfide oxidation in the presence of Mn and Fe oxides. Sea level at the Kelly's Cove watershed was approximately 80??m above present sea level about 13 000??years before present, imposing reducing conditions on that area of the watershed. Sea level dropped approximately 60??m below present sea level about 11 000??years before present, allowing for possible oxidation of sulfide minerals and precipitation of arsenic in ferric oxyhydroxides during aeration of the ground-water system. Under present redox conditions, there is evidence that bacteria reduction of ferric oxyhydroxides releases arsenic. The fractionation of 18O in the SO4 during anaerobic oxidation of sulfide in the presence of Mn and Fe oxides and subsequent release of arsenic during Mn and Fe oxide reduction may explain the relationship between high arsenic concentrations and elevated 18O[SO4] at Kelly's Cove. ?? 2007 Elsevier B.V. All rights reserved.

Lipfert, G.; Sidle, W. C.; Reeve, A. S.; Ayuso, R. A.; Boyce, A. J.

2007-01-01

198

Arsenic speciation and spatial and interspecies differences of metal concentrations in mollusks and crustaceans from a South China estuary.  

PubMed

Arsenic speciation and concentrations were determined in mollusks and crustaceans in the intertidal zone from twelve locations in Zhanjiang estuary, South China. Metal concentrations (Ag, As, Cd, Cu, Hg, Ni, Pb, and Zn) were also concurrently determined in these species. Arsenic speciation analysis showed that the less-toxic arsenobetaine (AsB) constituted 80.6-98.8 % of all As compounds, and dimethylarsinic acid (DMA) constituted 0.47-3.44 %. Monomethylarsonic acid (MMA) and As(V) were only detected in the whelk Drupa fiscella and the crab Heteropilumnus ciliatus, respectively. Arsenite [As(III)] was not detected in any of the sampled specimens, but there were also unidentified other As species. A strong spatial variation of metals in the oyster Saccostrea cucullata was found in the estuary, confirming that oysters can be used as a good biomonitor of metal contamination in the studied area. The concentrations of eight metals in the studied mollusks and crustaceans clearly revealed that these invertebrates accumulated different metals to different degrees. Furthermore, As, Cd, Cu, Hg, and Pb contents in mollusks and crustacean samples were below the Food and Agricultural Organization (FAO) safe concentrations, thus there was no obvious health risk from the intake of the metals through marine mollusks and crustaceans consumption. PMID:23475307

Zhang, Wei; Wang, Wen-Xiong; Zhang, Li

2013-05-01

199

Isoniazid/acetylisoniazid urine concentrations: markers of adherence to isoniazid preventive therapy in children.  

PubMed

The Arkansas colorimetric method monitors adherence to isoniazid (INH) by the detection of INH metabolites in urine. Urine samples 4 h after INH administration in 31 human immunodeficiency virus infected children receiving daily or thrice weekly INH preventive therapy were Arkansas test-positive for 29/31 (94%), while acetylisoniazid (AcINH) was detected in 30/31 (97%) using mass spectrometry. At 24, 48 and 72 h, only 78%, 23% and 0 samples, respectively, were Arkansas-positive, while INH or AcINH was detected in respectively 94%, 69% and 33%. The Arkansas test reliably predicted INH ingestion at a clinic visit 4 h after morning doses, but did not perform well at 24 h. PMID:24903787

Amlabu, V; Mulligan, C; Jele, N; Evans, A; Gray, D; Zar, H J; McIlleron, H; Smith, P

2014-05-01

200

Arsenic pollution sources.  

PubMed

Arsenic is a widely dispersed element in the Earth's crust and exists at an average concentration of approximately 5 mg/kg. There are many possible routes of human exposure to arsenic from both natural and anthropogenic sources. Arsenic occurs as a constituent in more than 200 minerals, although it primarily exists as arsenopyrite and as a constituent in several other sulfide minerals. The introduction of arsenic into drinking water can occur as a result of its natural geological presence in local bedrock. Arsenic-containing bedrock formations of this sort are known in Bangladesh, West Bengal (India), and regions of China, and many cases of endemic contamination by arsenic with serious consequences to human health are known from these areas. Significant natural contamination of surface waters and soil can arise when arsenic-rich geothermal fluids come into contact with surface waters. When humans are implicated in causing or exacerbating arsenic pollution, the cause can almost always be traced to mining or mining-related activities. Arsenic exists in many oxidation states, with arsenic (III) and (V) being the most common forms. Similar to many metalloids, the prevalence of particular species of arsenic depends greatly on the pH and redox conditions of the matrix in which it exists. Speciation is also important in determining the toxicity of arsenic. Arsenic minerals exist in the environment principally as sulfides, oxides, and phosphates. In igneous rocks, only those of volcanic origin are implicated in high aqueous arsenic concentrations. Sedimentary rocks tend not to bear high arsenic loads, and common matrices such as sands and sandstones contain lower concentrations owing to the dominance of quartz and feldspars. Groundwater contamination by arsenic arises from sources of arsenopyrite, base metal sulfides, realgar and orpiment, arsenic-rich pyrite, and iron oxyhydroxide. Mechanisms by which arsenic is released from minerals are varied and are accounted for by many (bio)geochemical processes: oxidation of arsenic-bearing sulfides, desorption from oxides and hydroxides, reductive dissolution, evaporative concentration, leaching from sulfides by carbonate, and microbial mobilization. Arsenic enrichment also takes place in geothermally active areas; surface waters are more susceptible than groundwater to contamination in the vicinity of such geothermal systems, and evidence suggests that increased use of geothermal power may elevate risks of arsenic exposure in affected areas. Past and current mining activities continue to provide sources of environmental contamination by arsenic. Because gold- and arsenic-bearing minerals coexist, there is a hazard of mobilizing arsenic during gold mining activities. The Ashanti region of central Ghana currently faces this as a real risk. Historical arsenic contamination exists in Cornwall, UK; an example of a recent arsenic pollution event is that of Ron Phibun town in southern Thailand, where arsenic-related human health effects have been reported. Other important sources of arsenic exposure include coal burning in Slovakia, Turkey, and the Guizhou Province of China; use of arsenic as pesticides in Australia, New Zealand, and the US; and consumption of contaminated foodstuffs (China) and exposure to wood preserving arsenicals (Europe and North America). PMID:18982996

Garelick, Hemda; Jones, Huw; Dybowska, Agnieszka; Valsami-Jones, Eugenia

2008-01-01

201

Oxidative damage in lymphocytes of copper smelter workers correlated to higher levels of excreted arsenic.  

PubMed

Arsenic has been associated with multiple harmful effects at the cellular level. Indirectly these defects could be related to impairment of the integrity of the immune system, in particular in lymphoid population. To characterize the effect of Arsenic on redox status on this population, copper smelter workers and arsenic unexposed donors were recruited for this study. We analyzed urine samples and lymphocyte enriched fractions from donors to determinate arsenic levels and lymphocyte proliferation. Moreover, we studied the presence of oxidative markers MDA, vitamin E and SOD activity in donor plasma. Here we demonstrated that in human beings exposed to high arsenic concentrations, lymphocyte MDA and arsenic urinary levels showed a positive correlation with SOD activity, and a negative correlation with vitamin E serum levels. Strikingly, lymphocytes from the arsenic exposed population respond to a polyclonal stimulator, phytohemaglutinin, with higher rates of thymidine incorporation than lymphocytes of a control population. As well, similar in vitro responses to arsenic were observed using a T cell line. Our results suggest that chronic human exposure to arsenic induces oxidative damage in lymphocytes and could be considered more relevant than evaluation of T cell surveillance. PMID:21253489

Escobar, Jorge; Varela-Nallar, Lorena; Coddou, Claudio; Nelson, Pablo; Maisey, Kevin; Valdés, Daniel; Aspee, Alexis; Espinosa, Victoria; Rozas, Carlos; Montoya, Margarita; Mandiola, Cristian; Rodríguez, Felipe E; Acuńa-Castillo, Claudio; Escobar, Alejandro; Fernández, Ricardo; Diaz, Hernán; Sandoval, Mario; Imarai, Mónica; Rios, Miguel

2010-01-01

202

High arsenic concentrations and enriched sulfur and oxygen isotopes in a fractured-bedrock ground-water system  

Microsoft Academic Search

Ground water with high arsenic concentrations (up to 26.6 ?mol L?1) has sulfate enriched in 34S and 18O in the fractured-bedrock, ground-water system of the Kelly's Cove watershed, Northport, Maine, USA. The ranges of sulfur and oxygen isotope values in aqueous sulfate, ?34S[SO4] and ?18O[SO4], at the Kelly's Cove watershed are +3.4 to +4.9‰ and ?2.0 to +6.7‰, respectively. These isotope

Gail Lipfert; William C. Sidle; Andrew S. Reeve; Robert A. Ayuso; Adrian J. Boyce

2007-01-01

203

The carcinogenicity of arsenic.  

PubMed Central

A carcinogenic role of inorganic arsenic has been suspected for nearly a century. Exposure to inorganic arsenic compounds occurs in some occupational groups, e.g., among smelter workers and workers engaged in the production and use of arsenic containing pesticides. Substantial exposure can also result from drinking water in certain areas and the use of some drugs. Tobacco and wine have had high As concentrations due to the use of arsenic containing pesticides. Inorganic arsenic compounds interfere with DNA repair mechanisms and an increased frequency of chromosomal aberrations have been observed among exposed workers and patients. Epidemiological data show that inorganic arsenic exposure can cause cancer of the lung and skin. The evidence of an etiologic role of arsenic for angiosarcoma of the liver is highly suggestive; however, the association between arsenic and cancer of other sites needs further investigation. No epidemiological data are available on exposure to organic arsenic compounds and cancer. Animal carcinogenicity studies involving exposure to various inorganic and organic arsenic compounds by different routes have been negative, with the possible exception of some preliminary data regarding lung cancer and leukemia. Some studies have indicated an increased mortality from lung cancer in populations living near point emission sources of arsenic into the air. The role of arsenic cannot be evaluated due to lack of exposure data. Epidemiological data suggest that the present WHO standard for drinking water (50 micrograms As/l.) provides only a small safety margin with regard to skin cancer.

Pershagen, G

1981-01-01

204

Urine and Urination  

MedlinePLUS

Your kidneys make urine by filtering wastes and extra water from your blood. The waste is called urea. Your blood carries it to the kidneys. From the kidneys, urine travels down two thin tubes called ureters to ...

205

Antioxidant-rich spice added to hamburger meat during cooking results in reduced meat, plasma, and urine malondialdehyde concentrations1234  

PubMed Central

Background: Emerging science has shown the effect of oxidation products and inflammation on atherogenesis and carcinogenesis. Cooking hamburger meat can promote the formation of malondialdehyde that can be absorbed after ingestion. Objective:We studied the effect of an antioxidant spice mixture on malondialdehyde formation while cooking hamburger meat and its effects on plasma and urinary malondialdehyde concentrations. Design: Eleven healthy volunteers consumed 2 kinds of burgers in a randomized order: one burger was seasoned with a spice blend, and one burger was not seasoned with the spice blend. The production of malondialdehyde in burgers and malondialdehyde concentrations in plasma and urine after ingestion were measured by HPLC. Results:Rosmarinic acid from oregano was monitored to assess the effect of cooking on spice antioxidant content. Forty percent (19 mg) of the added rosmarinic acid remained in the spiced burger (SB) after cooking. There was a 71% reduction in the malondialdehyde concentration (mean ± SD: 0.52 ± 0.02 ?mol/250 g) in the meat of the SBs compared with the malondialdehyde concentration (1.79 ± 0.17 ?mol/250 g) in the meat of the control burgers (CBs). The plasma malondialdehyde concentration increased significantly in the CB group as a change from baseline (P = 0.026). There was a significant time-trend difference (P = 0.013) between the 2 groups. Urinary malondialdehyde concentrations (?mol/g creatinine) decreased by 49% (P = 0.021) in subjects consuming the SBs compared with subjects consuming the CBs. Conclusions: The overall effect of adding the spice mixture to hamburger meat before cooking was a reduction in malondialdehyde concentrations in the meat, plasma, and urine after ingestion. Therefore, cooking hamburgers with a polyphenol-rich spice mixture can significantly decrease the concentration of malondialdehyde, which suggests potential health benefits for atherogenesis and carcinogenesis. This trial was registered at clinical trials.gov as NCT01027052.

Li, Zhaoping; Henning, Susanne M; Zhang, Yanjun; Zerlin, Alona; Li, Luyi; Gao, Kun; Lee, Ru-Po; Karp, Hannah; Thames, Gail; Bowerman, Susan

2010-01-01

206

Monomethylated trivalent arsenic species disrupt steroid receptor interactions with their DNA response elements at non-cytotoxic cellular concentrations  

PubMed Central

Arsenic (As) is considered a top environmental chemical of human health because it has been linked to adverse health effects including cancer, diabetes, cardiovascular disease, and reproductive and developmental problems. In several cell culture and animal models, As acts as an endocrine disruptor, which may underlie many of its health effects. Previous work showed that steroid receptor (SR)-driven gene expression is disrupted in cells treated with inorganic As (arsenite, iAs+3). In those studies, low iAs+3 concentrations (0.1–0.7 ?M) stimulated hormone-inducible transcription, whereas somewhat higher but still non-cytotoxic levels (1–3 ?M) inhibited transcription. This investigation focuses on the mechanisms underlying these inhibitory effects and evaluates the role of methylated trivalent As metabolites on SR function. Recent evidence suggests that, compared with iAs, methylated forms may have distinct biochemical effects. Here, fluorescence polarization (FP) experiments utilizing purified, hormone-bound human glucocorticoid (GR) and progesterone receptor (PR) have demonstrated that neither inorganic (iAs+3) nor dimethylated (DMA+3) species of trivalent As affect receptor interactions with glucocorticoid DNA response elements (GREs). However, monomethylated forms (monomethylarsenite, MMA+3 and monomethylarsonic diglutathione, MADG) strongly inhibit GR-GRE and PR-GRE binding. Additionally, speciation studies of iAs+3-treated H4IIE rat hepatoma cells show that, under treatment conditions that cause inhibition of hormone-inducible gene transcription, the intracellular concentration of MADG is sufficient to inhibit GR-GRE and PR-GRE interactions in vivo. These results indicate that arsenic’s inhibitory endocrine disruption effects are probably caused in part by methylated metabolites’ disruption of SR ability to bind DNA response elements that are crucial to hormone-driven gene transcription.

Gosse, Julie A.; Taylor, Vivien F.; Jackson, Brian P.; Hamilton, Joshua W.; Bodwell, Jack E.

2013-01-01

207

Concentrations of arsenic and heavy metals in vegetation at two abandoned mine tailings in South Korea  

Microsoft Academic Search

Untreated abandoned mines may result in hazards to ecosystems due to dispersion of various toxic elements such as arsenic\\u000a (As) and lead (Pb). Phytoremediation is an alternative of remediation for large scale mine dumps. Plant species were sampled\\u000a from two abandoned gold (Au) mines in South Korea. Plant samples were digested following the guidelines of US EPA Method 3050\\u000a (US-EPA,

Peichun Chang; Ju-Yong Kim; Kyoung-Woong Kim

2005-01-01

208

Urine concentrating mechanism in the inner medulla of the mammalian kidney: role of three-dimensional architecture.  

PubMed

The urine concentrating mechanism in the mammalian renal inner medulla (IM) is not understood, although it is generally considered to involve countercurrent flows in tubules and blood vessels. A possible role for the three-dimensional relationships of these tubules and vessels in the concentrating process is suggested by recent reconstructions from serial sections labelled with antibodies to tubular and vascular proteins and mathematical models based on these studies. The reconstructions revealed that the lower 60% of each descending thin limb (DTL) of Henle's loops lacks water channels (aquaporin-1) and osmotic water permeability and ascending thin limbs (ATLs) begin with a prebend segment of constant length. In the outer zone of the IM (i) clusters of coalescing collecting ducts (CDs) form organizing motif for loops of Henle and vasa recta; (ii) DTLs and descending vasa recta (DVR) are arrayed outside CD clusters, whereas ATLs and ascending vasa recta (AVR) are uniformly distributed inside and outside clusters; (iii) within CD clusters, interstitial nodal spaces are formed by a CD on one side, AVR on two sides, and an ATL on the fourth side. These spaces may function as mixing chambers for urea from CDs and NaCl from ATLs. In the inner zone of the IM, cluster organization disappears and half of Henle's loops have broad lateral bends wrapped around terminal CDs. Mathematical models based on these findings and involving solute mixing in the interstitial spaces can produce urine slightly more concentrated than that of a moderately antidiuretic rat but no higher. PMID:21054810

Dantzler, W H; Pannabecker, T L; Layton, A T; Layton, H E

2011-07-01

209

Arsenic removal from water  

DOEpatents

Methods for removing arsenic from water by addition of inexpensive and commonly available magnesium oxide, magnesium hydroxide, calcium oxide, or calcium hydroxide to the water. The hydroxide has a strong chemical affinity for arsenic and rapidly adsorbs arsenic, even in the presence of carbonate in the water. Simple and commercially available mechanical methods for removal of magnesium hydroxide particles with adsorbed arsenic from drinking water can be used, including filtration, dissolved air flotation, vortex separation, or centrifugal separation. A method for continuous removal of arsenic from water is provided. Also provided is a method for concentrating arsenic in a water sample to facilitate quantification of arsenic, by means of magnesium or calcium hydroxide adsorption.

Moore, Robert C. (Edgewood, NM); Anderson, D. Richard (Albuquerque, NM)

2007-07-24

210

Metabolites of arsenic and increased DNA damage of p53 gene in arsenic plant workers  

SciTech Connect

Recent studies have shown that monomethylarsonous acid is more cytotoxic and genotoxic than arsenate and arsenite, which may attribute to the increased levels of reactive oxygen species. In this study, we used hydride generation-atomic absorption spectrometry to determine three arsenic species in urine of workers who had been working in arsenic plants,and calculated primary and secondary methylation indexes. The damages of exon 5, 6, 8 of p53 gene were determined by the method developed by Sikorsky, et al. Results show that the concentrations of each urinary arsenic species,and damage indexes of exon 5 and 8 of p53 gene in the exposed population were significantly higher, but SMI was significantly lower than in the control group. The closely positive correlation between the damage index of exon 5 and PMI,MMA, DMA were found, but there was closely negative correlation between the damage index of exon 5 and SMI. Those findings suggested that DNA damage of exon 5 and 8 of p53 gene existed in the population occupationally exposed to arsenic. For exon 5, the important factors may include the model of arsenic metabolic transformation, the concentrations of MMA and DMA, and the MMA may be of great importance. - Research Highlights: > In our study, the mean SMI for workers came from arsenic plants is 4.06, so they may be in danger. > There are more MMA, there are more damage of exon 5 of p53 gene. > MMA and damage of exon 5 of p53 gene may be useful biomarkers to assess adverse health effects caused by arsenic.

Wen Weihua, E-mail: Dongsijiehua@sina.com [Department of Occupational Health, Yunnan Provincial Center for Disease Control and Prevention, No. 158, Dongsi Street, Kunming, Yunnan, 650022 (China); Public Health College, Huazhong University of Science and Technology, No. 13, Hangkong Road, Wuhan City, Hubei, 430030 (China); Wen Jinghua [Guizhou College of Finance and Economics, No. 276, Chongguan Road, Guiyang, Guizhou, 550004 (China); Lu Lin [Department of Occupational Health, Yunnan Provincial Center for Disease Control and Prevention, No. 158, Dongsi Street, Kunming, Yunnan, 650022 (China); Liu Hua [The First Affiliated Hospital of Kunming Medical College, No. 295 Xichang Road, Kunming, Yunnan, 650032 (China); Yang Jun; Cheng Huirong [Department of Occupational Health, Yunnan Provincial Center for Disease Control and Prevention, No. 158, Dongsi Street, Kunming, Yunnan, 650022 (China); Che Wangjun [The First Division of Public Health, Kunming Center for Disease Control and Prevention, No. 4, Ziyun Road, Xishan District, Kunming, Yunnan 650228 (China); Li Liang [Honghe Zhou Center for Disease Control and Prevention, No. 1, Guannan Road, Mengzi City, Yunnan, 661100 (China); Zhang Guanbei [Yunnan Institute for Drug Abuse, Kunming, 650028 (China)

2011-07-01

211

A mathematical model of the urine concentrating mechanism in the rat renal medulla. I. Formulation and base-case results  

PubMed Central

A new, region-based mathematical model of the urine concentrating mechanism of the rat renal medulla was used to investigate the significance of transport and structural properties revealed in anatomic studies. The model simulates preferential interactions among tubules and vessels by representing concentric regions that are centered on a vascular bundle in the outer medulla (OM) and on a collecting duct cluster in the inner medulla (IM). Particularly noteworthy features of this model include highly urea-permeable and water-impermeable segments of the long descending limbs and highly urea-permeable ascending thin limbs. Indeed, this is the first detailed mathematical model of the rat urine concentrating mechanism that represents high long-loop urea permeabilities and that produces a substantial axial osmolality gradient in the IM. That axial osmolality gradient is attributable to the increasing urea concentration gradient. The model equations, which are based on conservation of solutes and water and on standard expressions for transmural transport, were solved to steady state. Model simulations predict that the interstitial NaCl and urea concentrations in adjoining regions differ substantially in the OM but not in the IM. In the OM, active NaCl transport from thick ascending limbs, at rates inferred from the physiological literature, resulted in a concentrating effect such that the intratubular fluid osmolality of the collecting duct increases ?2.5 times along the OM. As a result of the separation of urea from NaCl and the subsequent mixing of that urea and NaCl in the interstitium and vasculature of the IM, collecting duct fluid osmolality further increases by a factor of ?1.55 along the IM.

2011-01-01

212

?LC-ICP-MS determinations of unexposed UK urinary arsenic speciation reference values.  

PubMed

This study provides background levels for five arsenic species in urine, based on urinary data obtained from 95 nonoccupationally exposed volunteers based in the UK. Using a novel, sensitive, robust and reliable speciation methodology, five species of arsenic (arsenobetaine [AB], arsenite [As(3+)], arsenate [As(5+)], monomethylarsonic acid [MMA(5+)] and dimethylarsinic acid [DMA(5+)]) were determined in urine samples collected from 95 adults. The analytical instrumentation used to analyze the urine samples was a hyphenated micro liquid chromatography (?LC) system coupled to an inductively coupled plasma mass spectrometry (ICP-MS). Separation was achieved using an anion exchange micro-sized column. The results presented give the 95th percentile of concentrations, both uncorrected for creatinine (µg/L) and creatinine corrected (µmol/mol) in urine for the 95 volunteers. Statistical analysis was performed on the dataset using a Bayesian model to determine and quantify effects of gender, smoking and diet. The statistical results show that the consumption of fish, shellfish and red wine has a significant elevating effect on AB, DMA and MMA urinary concentrations; however, no significant effect was observed for smoking. The regression model results indicate that creatinine correction was effective for arsenic species As(3+), MMA, DMA and AB. The background levels established here can be used as reference values to help aid interpretation of arsenic speciation results and better assess exposure. PMID:24187062

Leese, Elizabeth; Morton, Jackie; Tan, Emma; Gardiner, Philip H E; Carolan, Vikki A

2014-01-01

213

Analytical strategy for the determination of various arsenic species in landfill leachate containing high concentrations of chlorine and organic carbon by HPLC-ICPMS  

NASA Astrophysics Data System (ADS)

As a variety of wastes containing arsenic are disposed of in landfills, such facilities can play a prominent role in disseminating arsenic sources to the environment. Since it is widely recognized that arsenic toxicity is highly dependent on its species, accurate determination of various arsenic species should be considered as one of the essential goals to properly account for the potential health risk of arsenic in human and the environment. The inductively coupled plasma mass spectrometry linked to high performance liquid chromatography (HPLC-ICPMS) is acknowledged as one of the most important tools for the trace analysis of metallic speciation because of its superior separation capability and detectability. However, the complexity of matrices can cause severe interferences in the analysis results, which is the problem often encountered with HPLC-ICPMS system. High concentration of organic carbon in a sample solution causes carbon build-up on the skimmer and sampling cone, which reduces analytical sensitivity and requires a high maintenance level for its cleaning. In addition, argon from the plasma and chlorine from the sample matrix may combine to form 40Ar35Cl, which has the same nominal mass to charge (m/z) ratio as arsenic. In this respect, analytical strategy for the determination of various arsenic species (e.g., inorganic arsenite and arsenate, monomethylarsonic acid, dimethylarsinic acid, dimethyldithioarsinic acid, and arsenobetaine) in landfill leachate containing high concentrations of chlorine and organic carbon was developed in the present study. Solid phase extraction disk (i.e., C18 disk), which does not significantly adsorb any target arsenic species, was used to remove organic carbon in sample solutions. In addition, helium (He) gas was injected into the collision reaction cell equipped in ICPMS to collapse 40Ar35Cl into individual 40Ar and 35Cl. Although He gas also decreased arsenic intensity by blocking 75As, its signal to noise ratio significantly increased after injecting He gas. We demonstrated that the analytical strategy was achieved improved sensitivity for the determination of various arsenic species in the landfill leachate as one of the complex matrices.

Bae, J.; An, J.; Kim, J.; Jung, H.; Kim, K.; Yoon, C.; Yoon, H.

2012-12-01

214

[Study of arsenic concentration and distribution in shell sand of the shell ridge islands by hydride generation atomic fluorescence spectrometry].  

PubMed

The present paper determined the As concentration in shell sand of the shell ridge islands by hydride generation atomic fluorescence spectrometry, studied the distribution of As in shell sand of the shell ridge islands, analysed the correlations of As with other nutrient elements, and discussed the probably influencing factors affecting the As concentration and distribution in shell sand. The results showed that the range of the arsenic concentration in shell sand is between 0.78 and 8.76 mg x kg(-1), the average concentration is 3.11 mg x kg(-1), and this indicated that the As contamination of the shell ridge island is in clean level. The As concentration of the shell sand has a increasing trend followed by the increase with profile depth or the decrease with the particle size, and the difference in As concentrations in shell sand of different particle sizes reached the significant level (p < or = 0.05). The As concentration in shell sand has a very significant positive correlation with the concentrations of Cu, Zn and Mn as well as the TP and TK, whereas the correlations between As and TN or Fe are not significant. The pollutant of As in the shell sand mainly comes from the absorption and fixation by shell sand from the environment but not the accumulation of the shell organism during their growing up. PMID:24555397

Liu, Qing; Zhao, Xi-Mei; Xie, Wen-Jun; Sun, Jing-Kuan; Xia, Jiang-Bao; Lu, Zhao-Hua

2013-11-01

215

An Investigation of Normal Urine with a Creatinine Concentration Under the Cutoff of 20 mg/dL for Specimen Validity Testing in a Toxicology Laboratory(.).  

PubMed

In clinical and forensic toxicology laboratories, one commonly used method for urine specimen validity testing is creatinine concentration. In this study, workplace guidelines are examined to determine their relevance to forensic and clinical toxicology samples. Specifically, it investigates the occurrence of urine creatinine concentrations under 20 mg/dL and notes potential issues with factors influencing creatinine concentration by utilizing a simple, novel method consisting of cation-paring high-pressure liquid chromatography in tandem with ultraviolet detection to determine the creatinine concentration in 3019 donors. Of the 4227 sample population in this study, 209 (4.94%) were below the cutoff value of 20 mg/dL for dilute urine. Because there are many factors that can influence the urinary creatinine concentration, samples that have creatinine under the 20 mg/dL cutoff do not always implicate sample adulteration. PMID:24502684

Holden, Brad; Guice, Erica A

2014-05-01

216

Arsenic treatment considerations  

SciTech Connect

The best arsenic treatment technique for a given utility will depend on arsenic concentration and species in source water, other constituents in the water, existing treatment processes, treatment costs, and handling of residuals. To evaluate these issues, a national survey investigated arsenic occurrence and speciation in US drinking water sources. In general, total arsenic concentration was higher in groundwater than in surface water supplies. Particulate arsenic was more abundant than previously suspected, and more arsenate than arsenite was present. The cost of arsenic treatment increased in the following order: modified conventional treatment {much_lt} activated alumina or anion exchange < reverse osmosis. Nevertheless, the most cost-effective treatment still might not be best, because secondary treatment benefits and residuals handling should also be taken into account.

Chen, H.W. [Univ. of Colorado, Boulder, CO (United States). Dept. of Civil Engineering; Frey, M.M. [McGuire Environmental Consulting Inc., Denver, CO (United States); Clifford, D. [Univ. of Houston, TX (United States). Dept. of Civil and Environmental Engineering; McNeill, L.S.; Edwards, M. [Virginia Polytechnic Inst. and State Univ., Blacksburg, VA (United States). Dept. of Civil and Environmental Engineering

1999-03-01

217

Frequent Urination  

MedlinePLUS

... to urinate even more frequently. Many pregnant women leak some urine when coughing, laughing, sneezing or exercising. ... urinate. It may also force some urine to leak out, particularly if the muscles around the urethra ...

218

Bilirubin - urine  

MedlinePLUS

Conjugated bilirubin - urine; Direct bilirubin - urine ... Bilirubin is not normally found in the urine. ... Increased levels of bilirubin in the urine may be due to: Biliary tract disease Cirrhosis Gallstones in the biliary tract Hepatitis Liver disease ...

219

Urine chemistry  

MedlinePLUS

Chemistry - urine ... For this test, a clean-catch (midstream) urine sample is needed. For more information, see: Urine collection - clean catch . Some tests require that you collect all of your urine for 24 ...

220

Invasive squamous-cell carcinoma and arsenical keratoses.  

PubMed

A 42-year-old man presented with a six-month history of a slowly-enlarging ulcer on his right sole, a 30-year history of altered pigmentation of the trunk and extremities, and hyperkeratotic papules of the palms and soles. Histopathologic examination showed an invasive squamous-cell carcinoma of the right sole and hyperkeratosis with keratinocyte atypia of the left finger and left lateral foot. The clinical and histopathologic findings are consistent with chronic arsenicism, which most commonly occurs in the setting of drinking contaminated water or after occupational exposure. Evaluation should include a physical examination, basic laboratory work-up, and measurement of a 24-hour urine arsenic concentration. Vigilant surveillance for the development of cutaneous malignancies is required. Oral retinoids may be helpful in reducing hyperkeratosis secondary to chronic arsenicism. PMID:19061623

Elmariah, Sarina B; Anolik, Robert; Walters, Ruth F; Rosenman, Karla; Pomeranz, Miriam K; Sanchez, Miguel R

2008-01-01

221

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 Central

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

2013-01-01

222

The role of drinking water sources, consumption of vegetables and seafood in relation to blood arsenic concentrations of Jamaican children with and without Autism Spectrum Disorders.  

PubMed

Arsenic is a toxic metal with harmful effects on human health, particularly on cognitive function. Autism Spectrum Disorders (ASDs) are lifelong neurodevelopmental and behavioral disorders manifesting in infancy or early childhood. We used data from 130 children between 2 and 8 years (65 pairs of ASD cases with age- and sex-matched control), to compare the mean total blood arsenic concentrations in children with and without ASDs in Kingston, Jamaica. Based on univariable analysis, we observed a significant difference between ASD cases and controls (4.03 ?g/L for cases vs. 4.48 ?g/L for controls, P<0.01). In the final multivariable General Linear Model (GLM), after controlling for car ownership, maternal age, parental education levels, source of drinking water, consumption of "yam, sweet potato, or dasheen", "carrot or pumpkin", "callaloo, broccoli, or pak choi", cabbage, avocado, and the frequency of seafood consumption per week, we did not find a significant association between blood arsenic concentrations and ASD status (4.36 ?g/L for cases vs. 4.65 ?g/L for controls, P=0.23). Likewise, in a separate final multivariable GLM, we found that source of drinking water, eating avocado, and eating "callaloo, broccoli, or pak choi" was significantly associated with higher blood arsenic concentrations (all three P<0.05). Based on our findings, we recommend assessment of arsenic levels in water, fruits, and vegetables, as well as increased awareness among the Jamaican population regarding potential risks for various exposures to arsenic. PMID:22819887

Rahbar, Mohammad H; Samms-Vaughan, Maureen; Ardjomand-Hessabi, Manouchehr; Loveland, Katherine A; Dickerson, Aisha S; Chen, Zhongxue; Bressler, Jan; Shakespeare-Pellington, Sydonnie; Grove, Megan L; Bloom, Kari; Wirth, Julie; Pearson, Deborah A; Boerwinkle, Eric

2012-09-01

223

An analysis of workers' tritium concentration in urine samples as a function of time after intake at Korean pressurised heavy water reactors.  

PubMed

In general, internal exposure from tritium at pressurised heavy water reactors (PHWRs) accounts for ?20-40 % of the total radiation dose. Tritium usually reaches the equilibrium concentration after a few hours inside the body and is then excreted from the body with an effective half-life in the order of 10 d. In this study, tritium metabolism was reviewed using its excretion rate in urine samples of workers at Korean PHWRs. The tritium concentration in workers' urine samples was also measured as a function of time after intake. On the basis of the monitoring results, changes in the tritium concentration inside the body were then analysed. PMID:22511731

Kim, Hee Geun; Kong, Tae Young

2012-12-01

224

Glutathione-S-transferase-omega [MMA(V) reductase] knockout mice: Enzyme and arsenic species concentrations in tissues after arsenate administration  

SciTech Connect

Inorganic arsenic is a human carcinogen to which millions of people are exposed via their naturally contaminated drinking water. Its molecular mechanisms of carcinogenicity have remained an enigma, perhaps because arsenate is biochemically transformed to at least five other arsenic-containing metabolites. In the biotransformation of inorganic arsenic, GSTO1 catalyzes the reduction of arsenate, MMA(V), and DMA(V) to the more toxic + 3 arsenic species. MMA(V) reductase and human (hGSTO1-1) are identical proteins. The hypothesis that GST-Omega knockout mice biotransformed inorganic arsenic differently than wild-type mice has been tested. The livers of male knockout (KO) mice, in which 222 bp of Exon 3 of the GSTO1 gene were eliminated, were analyzed by PCR for mRNA. The level of transcripts of the GSTO1 gene in KO mice was 3.3-fold less than in DBA/1lacJ wild-type (WT) mice. The GSTO2 transcripts were about two-fold less in the KO mouse. When KO and WT mice were injected intramuscularly with Na arsenate (4.16 mg As/kg body weight); tissues removed at 0.5, 1, 2, 4, 8, and 12 h after arsenate injection; and the arsenic species measured by HPLC-ICP-MS, the results indicated that the highest concentration of the recently discovered and very toxic MMA(III), a key biotransformant, was in the kidneys of both KO and WT mice. The highest concentration of DMA(III) was in the urinary bladder tissue for both the KO and WT mice. The MMA(V) reducing activity of the liver cytosol of KO mice was only 20% of that found in wild-type mice. There appears to be another enzyme(s) other than GST-O able to reduce arsenic(V) species but to a lesser extent. This and other studies suggest that each step of the biotransformation of inorganic arsenic has an alternative enzyme to biotransform the arsenic substrate.

Chowdhury, Uttam K. [Department of Molecular and Cellular Biology, University of Arizona, Tucson, Arizona, 85721-0106 (United States); Zakharyan, Robert A. [Department of Molecular and Cellular Biology, University of Arizona, Tucson, Arizona, 85721-0106 (United States); Hernandez, Alba [Grup de Mutagenesi, Department of Genetica i de Microbiologia, Facultat de Ciencies, Universitat Autonoma de Barcelona, Campus de Bellaterra, 08193 Cerdanyola del Valles (Spain); Avram, Mihaela D. [Department of Molecular and Cellular Biology, University of Arizona, Tucson, Arizona, 85721-0106 (United States); Kopplin, Michael J. [College of Pharmacy, University of Arizona, Tucson, Arizona, 85721-0106 (United States); Aposhian, H. Vasken [Department of Molecular and Cellular Biology, University of Arizona, Tucson, Arizona, 85721-0106 (United States) and College of Pharmacy, University of Arizona, Tucson, Arizona, 85721-0106 (United States)]. E-mail: aposhian@u.arizona.edu

2006-11-01

225

Role of metabolism in arsenic toxicity.  

PubMed

In humans, as in most mammalian species, inorganic arsenic is methylated to methylarsonic acid (MMA) and dimethylarsinic acid (DMA) by alternating reduction of pentavalent arsenic to trivalent and addition of a methyl group from S-adenosylmethionine. The methylation of inorganic arsenic may be considered a detoxification mechanism, as the end metabolites, MMA and DMA, are less reactive with tissue constituents, less toxic, and more readily excreted in the urine than is inorganic arsenic, especially the trivalent form (AsIII, arsenite). The latter is highly reactive with tissue components, due to its strong affinity for sulfhydryl groups. Thus, following exposure to AsV the first step in the biotransformation, i.e. the reduction to AsIII, may be considered a bioactivation. Also, reactive intermediate metabolites of high toxicity, mainly MMAIII, may be formed and distributed to tissues. Low levels of MMAIII and DMAIII have been detected in urine of individuals chronically exposed to inorganic arsenic via drinking water. However, the contribution of MMAIIIand DMAIII to the toxicity observed after intake of inorganic arsenic by humans remains to be elucidated. The major route of excretion of arsenic is via the kidneys. Evaluation of the methylation of arsenic is mainly based on the relative amounts of the different metabolites in urine. On average human urine contains 10-30% inorganic arsenic, 10-20% MMA and 60-80% DMA. PMID:11484904

Vahter, M; Concha, G

2001-07-01

226

Effect of cattle urine addition on the surface emissions and subsurface concentrations of greenhouse gases from a UK lowland peatland.  

NASA Astrophysics Data System (ADS)

Grazing systems represent a substantial percentage of the global anthropogenic flux of nitrous oxide (N2O) as a result of nitrogen addition to the soil. Cattle urine has been shown to stimulate N2O production due to the dual effect of a large pool of readily available N and C and increased soil water content. Studies indicate that even short-term grazing can cause a significant increase in N2O emissions, particularly when combined with compaction and seasonal water-table rise. Peat soils have different physical and chemical characteristics to mineral soils including higher organic carbon content, higher porosity and greater variation in hydraulic properties due to swell and shrink. Peat soils have been shown to have increased N2O emissions with respect to mineral soils as a result of a combination of these factors, particularly when amended with fertilisers or livestock excreta. Many lowland peatland environments in the UK are under seasonal grazing management and cattle are increasingly being introduced to manage fen vegetation in lowland peatland. In this study, we simulated small urination events on a conservation area of UK peat grassland that is intensively grazed for a short period of time during autumn seasonal water-table rise. We measured subsurface and surface emissions of N2O, methane (CH4) and carbon dioxide (CO2) alongside soil physical and chemical changes to determine the key mechanisms of greenhouse gas production and transport. CO2emission peaked at 5200 mg CO2 m-2 d-1 directly after application from a background value of 905 mg CO2 m-2 d-1. CH4 flux decreased to -2000 ?g CH4 m-2 d-1two days after application (control plots -580 ?g CH4 m-2 d-1); however, net CH4 flux was positive from urine treated plots and negative from control plots. N2O emission peaked at 37 mg N2O m-2 d-1 12 days after application (1.08 mg N2O m-2 d-1 in control plots). Subsurface CH4 and N2O concentrations were higher in the urine treated plots than the controls. There was no effect of treatment on subsurface CO2 concentrations. Subsurface N2O peaked at 500ppm 12 days after and 1200ppm 56 days after application. Subsurface NO3- concentration peaked at approximately 300 mg N kg dry soil-112 days after application. Results indicate that denitrification is the key driver for N2O release in peatlands and that production is strongly related to increased soil moisture. N2O production at depth continued long after emissions were detected at the surface. Increased study of the interaction between subsurface gas concentrations, surface emissions and soil hydrological conditions is required to successfully predict greenhouse gas production and emission.

Boon, Alex; Robinson, Steve; Chadwick, David; Cardenas, Laura

2014-05-01

227

Arsenic removal during precipitative softening  

Microsoft Academic Search

Because utilities with hard waters tend to have higher concentrations of arsenic, removal of arsenic via precipitative softening processes was investigated in the context of the more stringent proposed arsenic regulation. Arsenic removal can be facilitated by a variety of solids formed during softening including CaCOâ, Mg(OH)â, Mn(OH)â, and Fe(OH)â. The extent of As(V) removal is decreased in the presence

Laurie S. McNeill; Marc Edwards

1997-01-01

228

Determination of arsenic in chicken feed by hydride generation atomic absorption spectrometry after pre-concentration with polyurethane foam.  

PubMed

A pre-concentration procedure with solid-phase extraction was developed for the determination of arsenic (As) in chicken feed using hydride generation atomic absorption spectrometry (HG-AAS). The procedure was based on the sorption of As(III) ions as complexes with ammonium pyrrolidine dithiocarbamate onto a mini-column packed with polyurethane foam. After pre-concentration, the As was removed from the mini-column by acid solution, and the analyte content in the eluate was measured by HG-AAS. The following main experimental conditions were established: adjustment of the As solution pH with 0.05?mol?l?ą HCl, 2.88?×?10?ł mol?l?ą complexing agent concentration and 6.0?mol?l?ą eluting hydrochloric acid concentration. The proposed method produced an enrichment factor of 67, with 0.050 and 0.165?µg?g?ą limits of detection and quantification, respectively. The procedure was applied to the determination of As content in two types of chicken feed using the proposed procedure and atomic absorption spectrometry with electrothermal atomisation (ETAAS). The t-test indicated that the results were not significantly different at a confidence level of 95%. PMID:22845621

Dos Passos, A S; Néri, T S; Maciel, M V; da Silva Romăo, I L; Lemos, V A

2012-01-01

229

Placental concentrations of mercury, lead, cadmium, and arsenic and the risk of neural tube defects in a Chinese population.  

PubMed

To examine whether in utero exposure to mercury (Hg), cadmium (Cd), lead (Pb) and arsenic (As) is associated with an elevated neural tube defects (NTDs) risk, placental concentrations of total Hg, Cd, Pb and As were measured with an inductively coupled plasma mass spectrometer (ICP-MS) in 36 anencephaly and 44 spina bifida cases as well as in 50 healthy controls. The median Hg concentration in the NTD cases (2.25 ng/g) was higher than that of the controls (1.16 ng/g). The odds ratio (OR) for an Hg concentration above the median was 8.80 (95% CI 3.80-20.36) for the NTD cases. NTD risks increased for the second and third high levels of the concentrations, with ORs of 2.70 (95% CI 1.13-6.43) and 18.20 (95% CI 5.45-60.73), respectively. Therefore, higher placental levels of Hg are associated with an elevated risk of NTDs. PMID:23164984

Jin, Lei; Zhang, Le; Li, Zhiwen; Liu, Jian-meng; Ye, Rrongwei; Ren, Aiguo

2013-01-01

230

Environmental tobacco smoke (ETS) exposure in children with asthma-relation between lead and cadmium, and cotinine concentrations in urine.  

PubMed

Exposure to heavy metals from environmental tobacco smoke (ETS) was investigated in 23 children with asthma (8.4+/-3.7 yr). ETS exposure was assessed by an inquiry data-based exposure index, the urinary concentration of cotinine (U-cotinine; a major nicotine metabolite) and the house dust (fine and coarse fractions) concentrations of nicotine at home. The corresponding concentrations of the heavy metals cadmium and lead in dust and urine (U-Cd; U-Pb) were determined in the same samples. There were strong associations between the ETS exposure index and U-cotinine (r(s)=0.62; P<0.002) and nicotine in house dust (r(s)=0.77; P<0.001). There was a strong positive correlation between lead and cadmium concentrations in both fine (r(s)=0.86; P<0.001) and coarse dust (r(s)=0.57; P=0.02). Although, there was a tendency for a relation between nicotine and lead concentrations in fine dust (r(s)=0.52; P=0.06), no other significant associations were found between house dust metals and nicotine concentrations. U-Cd correlated well with U-cotinine (r(s)=0.50; P=0.02). Further, U-Pb were associated with U-cotinine, however not statistically significant (r(s)=0.41; P=0.06). A probable explanation is a direct inhalation of side-stream smoke containing heavy metals and/ or an increased pulmonary uptake, due to a small airways disease in children with asthma. PMID:16291074

Willers, Stefan; Gerhardsson, Lars; Lundh, Thomas

2005-12-01

231

Arsenic exposure from drinking water and mortality from cardiovascular disease in Bangladesh: prospective cohort study  

PubMed Central

Objective To evaluate the association between arsenic exposure and mortality from cardiovascular disease and to assess whether cigarette smoking influences the association. Design Prospective cohort study with arsenic exposure measured in drinking water from wells and urine. Setting General population in Araihazar, Bangladesh. Participants 11?746 men and women who provided urine samples in 2000 and were followed up for an average of 6.6 years. Main outcome measure Death from cardiovascular disease. Results 198 people died from diseases of circulatory system, accounting for 43% of total mortality in the population. The mortality rate for cardiovascular disease was 214.3 per 100?000 person years in people drinking water containing <12.0 µg/L arsenic, compared with 271.1 per 100?000 person years in people drinking water with ?12.0 µg/L arsenic. There was a dose-response relation between exposure to arsenic in well water assessed at baseline and mortality from ischaemic heart disease and other heart disease; the hazard ratios in increasing quarters of arsenic concentration in well water (0.1-12.0, 12.1-62.0, 62.1-148.0, and 148.1-864.0 µg/L) were 1.00 (reference), 1.22 (0.65 to 2.32), 1.35 (0.71 to 2.57), and 1.92 (1.07 to 3.43) (P=0.0019 for trend), respectively, after adjustment for potential confounders including age, sex, smoking status, educational attainment, body mass index (BMI), and changes in urinary arsenic concentration since baseline. Similar associations were observed when baseline total urinary arsenic was used as the exposure variable and for mortality from ischaemic heart disease specifically. The data indicate a significant synergistic interaction between arsenic exposure and cigarette smoking in mortality from ischaemic heart disease and other heart disease. In particular, the hazard ratio for the joint effect of a moderate level of arsenic exposure (middle third of well arsenic concentration 25.3-114.0 µg/L, mean 63.5 µg/L) and cigarette smoking on mortality from heart disease was greater than the sum of the hazard ratios associated with their individual effect (relative excess risk for interaction 1.56, 0.05 to 3.14; P=0.010). Conclusions Exposure to arsenic in drinking water is adversely associated with mortality from heart disease, especially among smokers.

2011-01-01

232

In vivo XRF analysis of mercury: the relation between concentrations in the kidney and the urine  

Microsoft Academic Search

The objective of this study was to determine the concentrations of mercury in organs of occupationally exposed workers using in vivo X-ray fluorescence analysis. Twenty mercury exposed workers and twelve occupationally unexposed referents participated in the study. Their mercury levels in kidney, liver and thyroid were measured using a technique based on excitation with partly plane polarized photons. The mercury

J. Borjesson; L. Barregard; G. Sallsten; A. Schutz; R. Jonson; M. Alpsten; S. Mattsson

1995-01-01

233

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

234

Can folate intake reduce arsenic toxicity?  

PubMed Central

Arsenic-contaminated groundwater is a global environmental health concern. Inorganic arsenic is a known carcinogen, and epidemiologic studies suggest that persons with impaired arsenic metabolism are at increased risk for certain cancers, including skin and bladder carcinoma. Arsenic metabolism involves methylation to monomethylarsonic acid and dimethylarsinic acid (DMA) by a folate-dependent process. Persons possessing polymorphisms in certain genes involved in folate metabolism excrete a lower proportion of urinary arsenic as DMA, which may influence susceptibility to arsenic toxicity. A double-blind placebo-controlled trial in a population with low plasma folate observed that after 12 weeks of folic acid supplementation, the proportion of total urinary arsenic excreted as DMA increased and blood arsenic concentration decreased, suggesting an improvement in arsenic metabolism. Although no studies have directly shown that high folate intake reduces the risk of arsenic toxicity, these findings provide evidence to support an interaction between folate and arsenic metabolism.

Kile, Molly L; Ronnenberg, Alayne G

2014-01-01

235

Arsenic exposure in early pregnancy alters genome-wide DNA methylation in cord blood, particularly in boys.  

PubMed

Early-life inorganic arsenic exposure influences not only child health and development but also health in later life. The adverse effects of arsenic may be mediated by epigenetic mechanisms, as there are indications that arsenic causes altered DNA methylation of cancer-related genes. The objective was to assess effects of arsenic on genome-wide DNA methylation in newborns. We studied 127 mothers and cord blood of their infants. Arsenic exposure in early and late pregnancy was assessed by concentrations of arsenic metabolites in maternal urine, measured by high performance liquid chromatography-inductively coupled plasma mass spectrometry. Genome-wide 5-methylcytosine methylation in mononuclear cells from cord blood was analyzed by Infinium HumanMethylation450K BeadChip. Urinary arsenic in early gestation was associated with cord blood DNA methylation (Kolmogorov-Smirnov test, P-value<10-15), with more pronounced effects in boys than in girls. In boys, 372 (74%) of the 500 top CpG sites showed lower methylation with increasing arsenic exposure (r S -values>-0.62), but in girls only 207 (41%) showed inverse correlation (r S -values>-0.54). Three CpG sites in boys (cg15255455, cg13659051 and cg17646418), but none in girls, were significantly correlated with arsenic after adjustment for multiple comparisons. The associations between arsenic and DNA methylation were robust in multivariable-adjusted linear regression models. Much weaker associations were observed with arsenic exposure in late compared with early gestation. Pathway analysis showed overrepresentation of affected cancer-related genes in boys, but not in girls. In conclusion, early prenatal arsenic exposure appears to decrease DNA methylation in boys. Associations between early exposure and DNA methylation might reflect interference with de novo DNA methylation. PMID:24965135

Broberg, K; Ahmed, S; Engström, K; Hossain, M B; Jurkovic Mlakar, S; Bottai, M; Grandér, M; Raqib, R; Vahter, M

2014-08-01

236

Biological responses of duckweed ( Lemna minor L.) exposed to the inorganic arsenic species As(III) and As(V): effects of concentration and duration of exposure  

Microsoft Academic Search

The accumulation of arsenic (As) and physiological responses of Lemna minor L. under different concentration (0, 1, 4, 16 and 64 ?M) and duration (1, 2, 4 and 6 days) of two species As, NaAsO2 and Na2HAsO4·7H2O, were studied in hydroponics. The accumulation of both As species depended on As concentration and exposure duration. The\\u000a highest accumulation of As was found

Fatih Duman; Fatma Ozturk; Zeki Aydin

2010-01-01

237

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

238

Arsenic concentration in porewater of an alkaline coal ash disposal site: Roles of siderite precipitation/dissolution and soil cover.  

PubMed

The geochemical behavior of As in porewaters of an alkaline coal ash disposal site was investigated using multilevel samplers. The disposal site was in operation from 1983 until 1994 and was covered with 0.3-0.5m thick soils in 2001 when this study was initiated. Sequential extraction analyses and batch leaching experiments were also performed using the coal ash samples collected from the disposal site. The results suggest the important roles of siderite (FeCO(3)) precipitation/dissolution and soil cover, which have been ignored previously. Arsenic levels in the porewater were very low (average of 10microgL(-1)) when the site was covered with soil due to coprecipitation with siderite. The soil cover enabled the creation of anoxic conditions, which raised the Fe concentration by the reductive dissolution of Fe-(hydr)oxides. Because of the high alkalinity generated from the alkaline coal ash, even a small increase in the Fe concentration (0.66mgL(-1) on average) could cause siderite precipitation. When the soil cover was removed, however, an oxidizing condition was created and triggered the precipitation of dissolved Fe as (hydr)oxides. As a result, the dissolution of previously precipitated As-rich siderite caused higher As concentration in the porewater (average of 345microgL(-1)). PMID:19682722

Kim, Kangjoo; Park, Sung-Min; Kim, Jinsam; Kim, Seok-Hwi; Kim, Yeongkyoo; Moon, Jeong-Tae; Hwang, Gab-Soo; Cha, Wang-Seog

2009-09-01

239

Skin Cancer Risk in Relation to Toenail Arsenic Concentrations in a US Population-based Case-Control Study  

Microsoft Academic Search

Arsenic is a known carcinogen specifically linked to skin cancer occurrence in regions with highly contaminated drinking water or in individuals who took arsenic-containing medicines. Presently, it is unknown whether such effects occur at environmental levels found in the United States. To address this question, the authors used data collected on 587 basal cell and 284 squamous cell skin cancer

Margaret R. Karagas; Therese A. Stukel; J. Steven Morris; Tor D. Tosteson; Julia E. Weiss; Steven K. Spencer; E. Robert Greenberg

240

Isotope concentrations from 24-h urine and 3-h serum samples can be used to measure intestinal magnesium absorption in postmenopausal women.  

PubMed

Studies suggest a link between magnesium status and osteoporosis. One barrier to more conclusive research on the potential relation is measuring intestinal magnesium absorption (MgA), which requires the use of stable isotopes and a ?6-d stool or 3-d urine collection. We evaluated alternative methods of measuring MgA. We administered 2 stable magnesium isotopes to 15 postmenopausal women (cohort 1) aged 62 ± 8 y with a dietary magnesium intake of 345 ± 72 mg/d. Participants fasted from 1200 h to 0700 h and then consumed breakfast with ?23 mg of oral ˛?Mg and ?11 mg of i.v. ˛?Mg. We measured magnesium isotope concentrations in 72-h urine, spot urine (36, 48, 60, and 72 h), and spot serum (1, 3, and 5 h) samples collected after isotope dosing. We calculated MgA using the dose-corrected fraction of isotope concentrations from the 72-h urine collection. We validated new methods in 10 postmenopausal women (cohort 2) aged 59 ± 5 y with a dietary magnesium intake of 325 ± 122 mg/d. In cohort 1, MgA based on the 72-h urine collection was 0.28 ± 0.08. The 72-h MgA correlated most highly with 0-24 h urine MgA value alone (? = 0.95, P < 0.001) or the mean of the 0-24 h urine and the 3-h (? = 0.93, P < 0.001) or 5-h (? = 0.96, P < 0.001) serum MgA values. In cohort 2, Bland-Altman bias was lowest (-0.003, P = 0.82) using means of the 0-24 h urine and 3-h serum MgA values. We conclude that means of 0-24 h urine and 3-h serum MgA provide a reasonable estimate of 72-h MgA. However, if researchers seek to identify small changes in MgA, we recommend a 3-d urine or extended stool collection. PMID:24500940

Hansen, Karen E; Nabak, Andrea C; Johnson, Rachael Erin; Marvdashti, Sheeva; Keuler, Nicholas S; Shafer, Martin M; Abrams, Steven A

2014-04-01

241

Occurrence of trivalent monomethyl arsenic and other urinary arsenic species in a highly exposed juvenile population in Bangladesh.  

PubMed

Following reports of high cytotoxicity and mutagenicity of monomethyl arsonous acid (MMA(III)) and early reports of urinary MMA(III) in arsenic-exposed individuals, MMA(III) has often been included in population studies. Use of urinary MMA(III) as an indicator of exposure and/or health risk is challenged by inconsistent results from field studies and stability studies, which indicate potential artifacts. We measured urinary arsenic species in children chronically exposed to arsenic in drinking water, using collection, storage, and analysis methods shown to conserve MMA(III). MMA(III) was easily oxidized in sample storage and processing, but recoveries of 80% or better in spiked urine samples were achieved. Attempts to preserve the distribution of MMA between trivalent and pentavalent forms using complexing agents were unsuccessful and MMA(III) spiked into treated urine samples actually showed lower stability than in untreated samples. In 643 urine samples from a highly exposed population from the Matlab district in Bangladesh stored for 3-6 months at ?-70?°C, MMA(III) was detected in 41 samples, with an estimated median value of 0.3??g/l, and levels of MMA(III) above 1??g/l in only two samples. The low urinary concentrations in highly exposed individuals and known difficulties in preserving sample oxidation state indicate that urinary MMA(III) is not suitable for use as an epidemiological biomarker. PMID:23549402

Kalman, David A; Dills, Russell L; Steinmaus, Craig; Yunus, Md; Khan, Al Fazal; Prodhan, Md Mofijuddin; Yuan, Yan; Smith, Allan H

2014-01-01

242

Genetic polymorphisms in glutathione S-transferase (GST) superfamily and arsenic metabolism in residents of the Red River Delta, Vietnam  

SciTech Connect

To elucidate the role of genetic factors in arsenic metabolism, we investigated associations of genetic polymorphisms in the members of glutathione S-transferase (GST) superfamily with the arsenic concentrations in hair and urine, and urinary arsenic profile in residents in the Red River Delta, Vietnam. Genotyping was conducted for GST omega1 (GSTO1) Ala140Asp, Glu155del, Glu208Lys, Thr217Asn, and Ala236Val, GST omega2 (GSTO2) Asn142Asp, GST pi1 (GSTP1) Ile105Val, GST mu1 (GSTM1) wild/null, and GST theta1 (GSTT1) wild/null. There were no mutation alleles for GSTO1 Glu208Lys, Thr217Asn, and Ala236Val in this population. GSTO1 Glu155del hetero type showed higher urinary concentration of As{sup V} than the wild homo type. Higher percentage of DMA{sup V} in urine of GSTM1 wild type was observed compared with that of the null type. Strong correlations between GSTP1 Ile105Val and arsenic exposure level and profile were observed in this study. Especially, heterozygote of GSTP1 Ile105Val had a higher metabolic capacity from inorganic arsenic to monomethyl arsenic, while the opposite trend was observed for ability of metabolism from As{sup V} to As{sup III}. Furthermore, other factors including sex, age, body mass index, arsenic level in drinking water, and genotypes of As (+ 3 oxidation state) methyltransferase (AS3MT) were also significantly co-associated with arsenic level and profile in the Vietnamese. To our knowledge, this is the first study indicating the associations of genetic factors of GST superfamily with arsenic metabolism in a Vietnamese population.

Agusa, Tetsuro [Department of Legal Medicine, Shimane University Faculty of Medicine, Enya 89-1, Izumo 693-8501 (Japan); Center for Marine Environmental Studies (CMES), Ehime University, Bunkyo-cho 2-5, Matsuyama 790-8577 (Japan); Iwata, Hisato, E-mail: iwatah@agr.ehime-u.ac.j [Center for Marine Environmental Studies (CMES), Ehime University, Bunkyo-cho 2-5, Matsuyama 790-8577 (Japan); Fujihara, Junko [Department of Legal Medicine, Shimane University Faculty of Medicine, Enya 89-1, Izumo 693-8501 (Japan); Kunito, Takashi [Department of Environmental Sciences, Faculty of Science, Shinshu University, 3-1-1 Asahi, Matsumoto 390-8621 (Japan); Takeshita, Haruo [Department of Legal Medicine, Shimane University Faculty of Medicine, Enya 89-1, Izumo 693-8501 (Japan); Tu Binh Minh; Pham Thi Kim Trang; Pham Hung Viet [Center for Environmental Technology and Sustainable Development (CETASD), Hanoi University of Science, Vietnam National University, T3 Building, 334 Nguyen Trai Street, Thanh Xuan District, Hanoi (Viet Nam); Tanabe, Shinsuke [Center for Marine Environmental Studies (CMES), Ehime University, Bunkyo-cho 2-5, Matsuyama 790-8577 (Japan)

2010-02-01

243

Arsenic in Bangladesh Groundwater: from Science to Mitigation  

NASA Astrophysics Data System (ADS)

A large proportion of the populations of Bangladesh and other South Asian countries is at risk of contracting cancers and other debilitating diseases due to exposure to high concentrations of naturally occurring arsenic in groundwater supplied by millions of tube wells. Starting in January 2000, and in partnership with several Bangladeshi institutions, an interdisciplinary team of health, earth, and social scientists from Columbia University has focused its efforts to address this crisis on a 25 km2 region in Araihazar upazila, about 20 km northeast of Dhaka. The project started with the recording of the position and depth of ~6600 wells in the area, the collection of groundwater samples from these wells, and laboratory analyses for arsenic and a suite of other constituents. This was followed by the recruitment of 12,000 adult inhabitants of the area for a long-term cohort study of the effects of arsenic exposure, as well as cross-sectional studies of their children. This presentation will focus on (1) the extreme degree of spatial variability of arsenic concentrations in Bangladesh groundwater, (2) the notion that spatial variability hampers mitigation in the sense that it complicates predictions but also offers an opportunity for mitigation because many households live within walking or drilling distance of safe water, and (3) the implication of recent advances in our understanding of the mechanisms of arsenic mobilization for potential temporal changes in groundwater arsenic. In addition, (4) a unique data set documenting the response of 6500 households to 4 years of mitigation in Araihazar, supported by documented reductions in exposure to arsenic based on urine analyses, will be presented. The presentation will conclude with (5) a proposal for scaling up mitigation efforts to the rest of the country by targeting safe aquifers with information transmitted to the village level from a central data base using cellular phones.

van Geen, A.; Ahmed, K. M.; Graziano, J. H.

2004-12-01

244

Genotypic and environmental variation in cadmium, chromium, arsenic, nickel, and lead concentrations in rice grains*  

PubMed Central

Genotypic and environmental variation in Cd, Cr, As, Ni and Pb concentrations of grains, and the relationships between these heavy metals and Fe, Zn were investigated using 9 rice genotypes grown in 6 locations for two successive years. Significant genotypic variation was detected in the five heavy metal concentrations in grains, indicating the possibility to reduce the concentration of these heavy metals in grains through breeding approach. The environmental effect varied with metal, with Pb and Ni having greater variation than the other three metals. There was significant genotype-environment (location) interaction of the concentrations of all five heavy metals in grains, suggesting the importance of cultivar choice in producing rice with low heavy metal concentrations in grains for a given location. Correlation analysis showed that Cd and As, Cr and Ni, and As and Pb concentrations in rice grains were closely associated, and that Ni concentration in grains was negatively correlated with Zn concentration.

Cheng, Wang-da; Zhang, Guo-ping; Yao, Hai-gen; Wu, Wei; Xu, Min

2006-01-01

245

The use of hydrogel microparticles to sequester and concentrate bacterial antigens in a urine test for Lyme disease  

Microsoft Academic Search

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

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

246

Arsenic, iron, lead, manganese, and uranium concentrations in private bedrock wells in southeastern New Hampshire, 2012-2013  

USGS Publications Warehouse

Trace metals, such as arsenic, iron, lead, manganese, and uranium, in groundwater used for drinking have long been a concern because of the potential adverse effects on human health and the aesthetic or nuisance problems that some present. Moderate to high concentrations of the trace metal arsenic have been identified in drinking water from groundwater sources in southeastern New Hampshire, a rapidly growing region of the State (Montgomery and others, 2003). During the past decade (2000–10), southeastern New Hampshire, which is composed of Hillsborough, Rockingham, and Strafford Counties, has grown in population by nearly 48,700 (or 6.4 percent) to 819,100. These three counties contain 62 percent of the State’s population but encompass only about 22 percent of the land area (New Hampshire Office of Energy and Planning, 2011). According to a 2005 water-use study (Hayes and Horn, 2009), about 39 percent of the population in these three counties in southeastern New Hampshire uses private wells as sources of drinking water, and these wells are not required by the State to be routinely tested for trace metals or other contaminants. Some trace metals have associated human-health benchmarks or nonhealth guidelines that have been established by the U.S. Environmental Protection Agency (EPA) to regulate public water supplies. The EPA has established a maximum contaminant level (MCL) of 10 micrograms per liter (?g/L) for arsenic (As) and a MCL of 30 ?g/L for uranium (U) because of associated health risks (U.S. Environmental Protection Agency, 2012). Iron (Fe) and manganese (Mn) are essential for human health, but Mn at high doses may have adverse cognitive effects in children (Bouchard and others, 2011; Agency for Toxic Substances and Disease Registry, 2012); therefore, the EPA has issued a lifetime health advisory (LHA) of 300 ?g/L for Mn. Recommended secondary maximum contaminant levels (SMCLs) for Fe (300 ?g/L) and Mn (50 ?g/L) were established primarily as nonhealth guidelines—based on aesthetic considerations, such as taste or the staining of laundry and plumbing fixtures—because these contaminants, at the SMCLs, are not considered to present risks to human health. Because lead (Pb) contamination of drinking water typically results from corrosion of plumbing materials belonging to water-system customers but still poses a risk to human health, the EPA established an action level (AL) of 15 ?g/L for Pb instead of an MCL or SMCL (U.S. Environmental Protection Agency, 2012). The 15-?g/L AL for Pb has been adopted by the New Hampshire Department of Environmental Services for public water systems, and if exceeded, the public water system must inform their customers and undertake additional actions to control corrosion in the pipes of the distribution system (New Hampshire Department of Environmental Services, 2013). Unlike the quality of drinking water provided by public water suppliers, the quality of drinking water obtained from private wells in New Hampshire is not regulated; consequently, private wells are sampled only when individual well owners voluntarily choose to sample them. The U.S. Geological Survey (USGS), in cooperation with the EPA New England, conducted an assessment in 2012–13 to provide private well owners and State and Federal health officials with information on the distribution of trace-metal (As, Fe, Pb, Mn, and U) concentrations in groundwater from bedrock aquifers in the three counties of southeastern New Hampshire. This fact sheet analyzes data from water samples collected by a randomly selected group of private well owners from the three-county study area and describes the major findings for trace-metal concentrations.

Flanagan, Sarah M.; Belaval, Marcel; Ayotte, Joseph D.

2014-01-01

247

Relative Bioavailability of Arsenic in Soils from Butte, Montana.  

National Technical Information Service (NTIS)

The gastrointestinal absorption of arsenic from soil samples collected from residential properties at the Butte Arsenic Superfund site was measured using young swine. Test materials include composite soil with arsenic concentrations of 234 ppm (TM1) and 3...

S. Morris S. W. Casteel T. J. Evans W. J. Brattin

2003-01-01

248

Environmental exposure to arsenic, AS3MT polymorphism and prevalence of diabetes in Mexico  

PubMed Central

Exposure to arsenic in drinking water is associated with increased prevalence of diabetes. We previously reported an association of diabetes and urinary concentration of dimethylarsinite (DMAsIII), a toxic product of arsenic methylation by arsenic ( +3 oxidation state) methyltransferase (AS3MT). Here we examine associations between AS3MT polymorphism, arsenic metabolism and diabetes. Fasting blood glucose, oral glucose tolerance and self-reported diagnoses were used to identify diabetic individuals. Inorganic arsenic and its metabolites were measured in urine. Genotyping analysis focused on six polymorphic sites of AS3MT. Individuals with M287T and G4965C polymorphisms had higher levels of urinary DMAsIII and were more frequently diabetic than the respective wild-type carriers, although the excess was not statistically significant. Odds ratios were 11.4 (95% confidence interval (CI) 2.2–58.8) and 8.8 (95% CI 1.6–47.3) for the combined effects of arsenic exposure >75th percentile and 287T and 4965C genotypes, respectively. Carriers of 287T and 4965C may produce more DMAsIII and be more likely to develop diabetes when exposed to arsenic.

Drobna, Zuzana; Del Razo, Luz M.; Garcia-Vargas, Gonzalo G.; Sanchez-Pena, Luz C.; Barrera-Hernandez, Angel; Styblo, Miroslav; Loomis, Dana

2014-01-01

249

The influence of groundwater chemistry on arsenic concentrations and speciation in a quartz sand and gravel aquifera)  

PubMed Central

We examined the chemical reactions influencing dissolved concentrations, speciation, and transport of naturally occurring arsenic (As) in a shallow, sand and gravel aquifer with distinct geochemical zones resulting from land disposal of dilute sewage effluent. The principal geochemical zones were: (1) the uncontaminated zone above the sewage plume [350 ?M dissolved oxygen (DO), pH 5.9]; (2) the suboxic zone (5 ?M DO, pH 6.2, elevated concentrations of sewage-derived phosphate and nitrate); and (3) the anoxic zone [dissolved iron(II) 100–300 ?M, pH 6.5–6.9, elevated concentrations of sewage-derived phosphate]. Sediments are comprised of greater than 90% quartz but the surfaces of quartz and other mineral grains are coated with nanometer-size iron (Fe) and aluminum (Al) oxides and/or silicates, which control the adsorption properties of the sediments. Uncontaminated groundwater with added phosphate (620 ?M) was pumped into the uncontaminated zone while samples were collected 0.3 m above the injection point. Concentrations of As(V) increased from below detection (0.005 ?M) to a maximum of 0.07 ?M during breakthrough of phosphate at the sampling port; As(III) concentrations remained below detection. These results are consistent with the hypothesis that naturally occurring As(V) adsorbed to constituents of the coatings on grain surfaces was desorbed by phosphate in the injected groundwater. Also consistent with this hypothesis, vertical profiles of groundwater chemistry measured prior to the tracer test showed that dissolved As(V) concentrations increased along with dissolved phosphate from below detection in the uncontaminated zone to approximately 0.07 and 70 ?M, respectively, in the suboxic zone. Concentrations of As(III) were below detection in both zones. The anoxic zone had approximately 0.07 ?M As(V) but also had As(III) concentrations of 0.07–0.14 ?M, suggesting that release of As bound to sediment grains occurred by desorption by phosphate, reductive dissolution of Fe oxides, and reduction of As(V) to As(III), which adsorbs only weakly to the Fe-oxide-depleted material in the coatings. Results of reductive extractions of the sediments suggest that As associated with the coatings was relatively uniformly distributed at approximately 1 nmol/g of sediment (equivalent to 0.075 ppm As) and comprised 20%-50% of the total As in the sediments, determined from oxidative extractions. Quartz sand aquifers provide high-quality drinking water but can become contaminated when naturally occurring arsenic bound to Fe and Al oxides or silicates on sediment surfaces is released by desorption and dissolution of Fe oxides in response to changing chemical conditions.

Kent, Douglas B; Fox, Patricia M

2004-01-01

250

SELENIUM and arsenic concentrations in platinum group minerals of placer origin from Borneo and Sierra Leone  

NASA Astrophysics Data System (ADS)

Laurite grains were examined from the type locality, Pontijn River, Tanah Laur, Borneo and from South Tambanio River, S.E. Borneo, and erlichmanite grains from Sierra Leone. The Borneo samples are associated with ophiolite (Alpine-type) ultramafic rocks and the Sierra Leone samples with the layered Freetown Igneous Complex. Laurite grains from Borneo are sub-rounded to spherical with pits and show conchoidal fractures. They contain rare inclusions of an exsolved chalcopyrite+ bornite+ pentlandite mixture. On the other hand, the erlichmanite grains from Sierra Leone are euhedral with minor smooth edges and contain abundant rounded inclusions of exsolved sulphides;(chalcopyrite +bornite) and (chalcopyrite+ pentlandite+ pyrrhotite). All grains examined are solid solutions of Ru and Os with minor to moderate Ir and Rh (mostly less than 1wt percent, and rarely over 5 wt percent). Arsenic contents vary from 0.4 to 1.3 wt percent and Se from 40 to 620 ppm and the two are correlated. Grains with less Se contain greater amounts of As; [As] = -55 x [Se]+ 16,000 (ppm). The evidence supports their presence at the S site, but the huge departure from 1:1 correlation is not understood. The laurite grains from Borneo are relatively homogeneous, showing rare zoning of Ru and Os. Ratios of S/Se show a narrow spread from 1600 to 2400, which are in the range for sulphides from the shallow, sub-arc mantle (Hattori et al., 2002). The data support their formation in the mantle and subsequent erosion after the obduction of the host ultramafic rocks. The laurite-erlichmanite from Sierra Leone show complicated internal zoning of Ru and Os, as shown pictorially previously (Hattori et al., 1991). The contents of Se and As systematically vary with Ru and Os. The Ru-rich parts (close to laurite composition) are enriched in Se and depleted in As. Furthermore; chalcopyrite inclusions contain even higher Se and lower As than the host laurite/erlichmanite. They show a narrow spread from 1650 to 2100 in S/Se and the host erlichmanite from 2500 to 5900. The weighted averages of S/Se of individual grains are approximately 3500, which is close to the primitive mantle value of 3300. The mineralogy and compositions support the formation of PGM during the solidification or subsolidus high-temperature magmatic hydrothermal activity of the Freetown Complex.

Hattori, K. H.; Johanson, B.; Cabri, L. J.

2003-04-01

251

Investigating concentration distributions of arsenic, gold and antimony in grain-size fractions of gold ore using instrumental neutron activation analysis.  

PubMed

Instrumental neutron activation analysis (INAA) has been used to quantify concentrations of arsenic (As), gold (Au) and antimony (Sb) in grain-size fractions of a gold ore. The ore, which was taken from the Ahafo project site of Newmont Ghana Gold Ltd., was fractionated into 14 grain-size fractions using state-of-the-art analytical sieve machine. The minimum sieve mesh size used was 36mum and grains >2000mum were not considered for analysis. Result of the sieving was analysed with easysieve(R) software. The<36mum subfraction was found to be the optimum, hosting bulk of all three elements. Arsenic was found to be highly concentrated in<36-100mum size fractions and erratically distributed in from 150mum fraction and above. For gold, with the exception of the subfraction <36mum which had exceptionally high concentration, the element was found to be approximately equally distributed in all the size fractions but slightly "played out" in 150-400mum size fractions. Antimony occurrence in the sample was relatively high in <36mum size fraction followed by 600, 800, 400 and 36mum size fractions in that order. Gold content in the sample was comparatively far greater than arsenic and antimony; this is indicative of level of gold mineralization in the concession where the sample ore was taken. The concentration of gold in the composite sample was in the range 564-8420ppm as compared to 14.33-186.92ppm for arsenic and 1.09-9.48ppm for antimony. Elemental concentrations were correlated with each other and with grain-size fractions and the relationships between these descriptive parameters were established. PMID:19896855

Nyarku, M; Nyarko, B J B; Serfor-Armah, Y; Osae, S

2010-02-01

252

Association of exposure to polycyclic aromatic hydrocarbons (estimated from job category) with concentration of 1-hydroxypyrene glucuronide in urine from workers at a steel plant.  

PubMed Central

OBJECTIVES--Increased risk of lung cancer has been associated with employment in the steel industry. This association is thought to be due in part to increased concentrations of polycyclic aromatic hydrocarbons (PAHs) in air found in this work environment. Measurement of PAH metabolites in human urine provides a means of assessing individual internal dose of PAHs. This study examined the relative contribution of occupation and smoking to urinary concentration of 1-hydroxypyrene glucuronide (1-OHPG) among a group of workers at a steel plant. METHODS--Concentrations of 1-OHPG in urine from 44 workers with jobs associated with increased air concentrations of PAHs and 40 workers with jobs with low or no exposure to PAHs were measured. 20 workers in each group were not current smokers. Urinary 1-OHPG was measured by synchronous fluorescence spectroscopy after immunoaffinity chromatography specific for PAH metabolites. RESULTS--Mean (SEM) urinary 1-OHPG concentration was 2.16 (0.42) pmol/ml urine among the 44 occupationally exposed workers compared with 0.38 (0.05) among the 40 workers with no or low exposure (P < 0.0001). Mean urinary 1-OHPG concentration was 1.82 (0.41) pmol/ml urine among the 44 current smokers compared with 0.75 (0.20) among the 40 non-smokers (P < 0.005). Mean 1-OHPG concentrations in non-smokers were 0.26 (n = 20), 0.70 (n = 15), and 2.84 pmol/ml urine (n = 5) for strata of exposure to PAHs (no or low, mid, and high) based on job category; the corresponding values in smokers were 0.55 (n = 20), 0.94 (n = 12), and 4.91 pmol/ml (n = 12), respectively. Multiple linear regression showed significant differences between subjects in different PAH exposure with increased concentrations of 1-OHPG in urine. Amounts of foods containing PAHs ingested by this group of workers were relatively low and did not contribute significantly to urinary 1-OHPG concentrations. CONCLUSIONS--These results indicate that 1-OHPG is a common urinary metabolite in people with recent occupational exposure to PAHs and is associated with both job category and estimated stratum of PAH exposure.

Kang, D; Rothman, N; Cho, S H; Lim, H S; Kwon, H J; Kim, S M; Schwartz, B; Strickland, P T

1995-01-01

253

Urinary arsenic methylation profile in children exposed to low arsenic levels through drinking water  

Microsoft Academic Search

There is a lack of information on arsenic metabolism in children exposed chronically to low levels of arsenic (<50 µg L). The objective of this study was to determine the methylation profile of urinary arsenic metabolites in children exposed to low-level concentrations of arsenic via their drinking water. A cross-sectional study was undertaken in 50 children from four towns in

Maria M. Meza-Montenegro; Michael J. Kopplin; Jefferey L. Burgess; A. Jay Gandolfi

2008-01-01

254

Concentration dependence and interfacial instabilities during ion beam annealing of arsenic-doped silicon  

SciTech Connect

Ion beam induced epitaxy of amorphous Si layers onto {l angle}100{r angle} substrates has been investigated by varying the As concentration. At As concentrations below 4{times}10{sup 18}/cm{sup 3} no rate effect is observed. In the intermediate regime, between 4{times}10{sup 18}/cm{sup 3} and 2{times}10{sup 21}/cm{sup 3}, the growth rate increases linearly with the logarithm of As concentration and reaches a value about a factor of 2 higher than that of intrinsic Si. At concentrations above 2{times}10{sup 21}/cm{sup 3}, the epitaxy experiences a sudden, severe retardation. Finally, at a concentration of {similar to}6{times}10{sup 21}/cm{sup 3}, twins are observed to form.

Priolo, F.; Rimini, E. (Dipartimento di Fisica, Corso Italia 57, I-95129 Catania, Italy (IT)); Spinella, C. (Istituto di Metodologie e Tecnologie per la Microelettronica, CNR, Catania, (IT)); Ferla, G. (SGS-Thomson, Stradale Primosole 50, I-95100 Catania, (IT))

1990-01-01

255

Declining Temporal Variability of Major Ions Concentrations but not Arsenic Concentration as Function of Groundwater age in the Ganges-Brahmaputra-Meghna Delta of Bangladesh  

NASA Astrophysics Data System (ADS)

Elevated arsenic concentrations in groundwater of the Ganges-Brahmaputra-Meghna (GBM) delta region pose a devastating health threat. One issue of considerable uncertainty is the magnitude of temporal variations in groundwater As concentrations. Despite the importance of the issue, there are very few high quality, long-term, time series data for groundwater As from the region. This presentation addresses the issue with a series of samples from Araihazar, Bangladesh, that were collected biweekly or monthly between 2001 and 2004 and analyzed by high resolution inductively-coupled plasma mass spectrometry. The method is precise (better than 5 percent long-term reproducibility for As and generates data for 32 other elements. Our study site comprises six nests of monitoring wells installed in an area where the hydrology and geochemistry have been carefully studied. Dissolved As concentrations range from < 1 ug/L to 600 ug/L in the shallow Holocene aquifer (upper 30 m) and mostly < 1 ug/L (As < 1-6.6 ug/L) in the deep Pleistocene aquifer (> 30 m depth). Dating of shallow aquifer water resulted in tritium-helium ages ranging from < 1 yr to > 40 yr. Deep Pleistocene aquifer water was 14C-dated and found to be up to thousands of years old. In the shallow aquifers, variations in groundwater As concentrations in all but 2 out of 28 wells did not display any discernable pattern linked to seasonal water table fluctuations. In addition, As concentration fluctuations were limited (0-15 percent) in all 28 wells. The two wells displayed seasonal pattern of As variations (10-15 percent) were particularly shallow (depths 6 m and 9 m). Redox-sensitive indicators such as Fe and Mn in both wells also displayed seasonal pattern. In contrast to As, most of wells with tritium-helium ages <21 years showed much larger variations in dissolved Cl- concentrations (10-43 percent) and total dissolved cations (5-31 percent) concentrations. Temporal variability was considerably reduced for groundwater >21 years old: 6-7 percent and 10-14 percent, major cations and anions, respectively. This suggests that despite the apparent influence of recharge on major ion concentrations, dissolved As concentrations in most shallow aquifers are relatively well buffered. No notable variability (<2 percent) in As concentrations was observed in groundwaters from the Pleistocene aquifer.

Dhar, R. K.; Zheng, Y.; Stute, M.; Cheng, Z.; Vangeen, A.; Shamsudduha, M.; Hoque, M. A.; Shanewaz, M.; Ahmed, K.

2004-12-01

256

Association of oxidative stress with arsenic methylation in chronic arsenic-exposed children and adults  

SciTech Connect

Though oxidative stress is recognized as an important pathogenic mechanism of arsenic, and arsenic methylation capacity is suggested to be highly involved in arsenic-related diseases, the association of arsenic methylation capacity with arsenic-induced oxidative stress remains unclear. To explore oxidative stress and its association with arsenic methylation, cross-sectional studies were conducted among 208 high and 59 low arsenic-exposed subjects. Levels of urinary arsenic species [inorganic arsenic (iAs), monomethylated arsenic (MMA) and dimethylated arsenic (DMA)] were determined by hydride generation atomic absorption spectrometry. Proportions of urinary arsenic species, the first methylation ratio (FMR) and the secondary methylation ratio (SMR) were used as indicators for arsenic methylation capacity. Urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG) concentrations were analyzed by enzyme-linked immunosorbent assay kits. Reduced glutathione (GSH) levels and superoxide dismutase (SOD) activity in whole blood were determined to reflect anti-oxidative status. The high arsenic-exposed children and adults were significantly increased in urinary 8-OHdG concentrations but decreased in blood GSH levels compared with the low exposed children and adults. In multiple linear regression models, blood GSH levels and urinary 8-OHdG concentrations of arsenic-exposed children and adults showed strong associations with the levels of urinary arsenic species. Arsenic-exposed subjects in the lower and the upper quartiles of proportions of urinary arsenic species, FMR or SMR were significantly different in urinary 8-OHdG, blood GSH and SOD. The associations of arsenic methylation capacity with 8-OHdG, GSH and SOD were also observed in multivariate regression analyses. These results may provide linkage between arsenic methylation capacity and oxidative stress in humans and suggest that adverse health effects induced by arsenic are related to arsenic methylation through oxidative stress.

Xu Yuanyuan; Wang Yi; Zheng Quanmei; Li Xin; Li Bing; Jin Yaping [Department of Occupational and Environmental Health, College of Public Health, China Medical University, No. 92 Bei Er Road, Heping District, Shenyang, 110001 (China); Sun Xiance [Hygiene Department, College of Basic Medical Sciences, Dalian Medical University, Dalian, Liaoning (China); Sun Guifan [Department of Occupational and Environmental Health, College of Public Health, China Medical University, No. 92 Bei Er Road, Heping District, Shenyang, 110001 (China)], E-mail: sungf@mail.cmu.edu.cn

2008-10-01

257

Urinary Arsenic Speciation and its Correlation with 8-OHdG in Chinese Residents Exposed to Arsenic Through Coal Burning  

Microsoft Academic Search

In contrast to arsenicosis caused by consumption of water contaminated by naturally occurring inorganic arsenic, human exposure\\u000a to this metalloid through coal burning has been rarely reported. In this study, arsenic speciation and 8-hydroxy-2?-deoxyguanosine\\u000a (8-OHdG) levels in urine were determined in the Chinese residents exposed to arsenic through coal burning in Guizhou, China,\\u000a an epidemic area of chronic arsenic poisoning

Xin Li; Jingbo Pi; Bing Li; Yuanyuan Xu; Yaping Jin; Guifan Sun

2008-01-01

258

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

259

Urine melanin  

MedlinePLUS

Thormahlen's test; Melanin - urine ... A clean-catch urine sample is needed. ... this substance that it shows up in the urine. ... Normally, melanin is not present in urine. Normal value ranges may ... measurements or test different samples. Talk to your doctor ...

260

Comparison of different medical cases in urinary arsenic speciation by fast HPLC-ICP-MS.  

PubMed

The inorganic arsenic species As(III), As(V) and the organic species methylarsonate (MMA(V)), dimethylarsinate (DMA(V)) and arsenobetaine (AsB) were determined in human urine by a fast anion exchange HPLC-ICP-MS method, which was developed for clinical laboratories with high sample throughput. This paper compares typical chromatograms of the arsenic species in urine samples collected in different medical cases, for example, for the non-exposed population, for environmentally (plant protectants) and occupationally (glass manufacture) exposed persons, for a person after a failed suicide attempt with As2O3 and for persons before and after administration of the antidot sodium 2,3-dimercapto-1-propane-sulfonate (DMPS). Concentration data of the urinary As species for the non-exposed German population (n=82) are compared with the concentrations before and after administration of DMPS (n=37). For the non-exposed group the toxicologically relevant As in urine consists of 81% DMA(V), 10% MMA(V) and 9% inorganic As. However, a few hours after an acute intoxication with inorganic As this distribution changes dramatically and As(III) and As(V) are predominantly found in urine. After treatment with DMPS the total As concentration increases significantly and mainly MMA(V) and As(III) were found in urine samples. PMID:18948060

Heitland, Peter; Köster, Helmut D

2009-07-01

261

Pb, Cd, Se, As in blood and urine of children from high and low polluted districts of Saint-Petersburg. The elements concentrations and health of children  

NASA Astrophysics Data System (ADS)

At present time rapt attention is attended on child health. One of the main factors of child health is environmental condition and possibility of toxic elements consuniption by children from air, water, and food. The ain of our investigation is to detennine Pb, Cd, Se, As in blood and urine of children from high and low level polluted districts of St.-Petersburg. And then to estimate urine and blood toxic elements concentration correlation. ln order to examine large child groups it is necessary to use effective, express analycal methods. Wc chose Zeeman Modulation Polarization Atomic Absorption Spectrometry with High-Frequency Modulation as such a method. New technique Zeeman Modulation Polarization Atomic Absorption Spectrometry with High-Frequency Modulation allow io determine many etements directly (without additional compounds and reagents or with there minimum use) in blood, plasma and urine. Highcst spectrometry selectivity allows working with high background level. The matrix effects are reduced in great deal the aid of L'vov platform, sample pyrolysis and palladium modifier using. We present the results of our investigation the concentration of toxic éléments in blood and urine of children from high Polluted district is above permitted level.

Lakovleva, E. M.; Ganeev, A. A.; Ivanenko, A. A.; Ivanenko, N. B.; Nosova, E.; Molodkina, E. V.; Kuzmenkov, M. A.

2003-05-01

262

Fate of Arsenic in Swine Waste from Concentrated Animal Feeding Operations  

Microsoft Academic Search

Swine diets are often supplemented by organoarsenicals, such as 3-nitro-4-hydroxyphenylarsonic acid (roxarsone) to treat animal diseases and promote growth. Recent work reported roxarsone degradation under anaerobic conditions in poultry litter, but no such data exist for swine wastes typically stored in lagoons nearby concentrated animal feeding operations (CAFOs). Th e objectives of this study were to: (i) characterize a suite

Konstantinos C. Makris; Shahida Quazi; Pravin Punamiya; Dibyendu Sarkar; Rupali Datta

2008-01-01

263

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

2012-09-01

264

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

PubMed Central

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 (AT1a) receptor-deficient (Agtr1a?/?) mice to test the hypothesis that AT1a 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 AT1a receptor-mediated ANG II signaling is required to maintain tonic AVP release and regulate V2 receptor-mediated responses to water deprivation in the inner medulla.

Li, Xiao C.; Shao, Yuan

2012-01-01

265

Urinary arsenic levels in the French adult population: the French National Nutrition and Health Study, 2006-2007.  

PubMed

The French Nutrition and Health Survey (ENNS) was conducted to describe dietary intakes, nutritional status, physical activity, and levels of various biomarkers for environmental chemicals (heavy metals and pesticides) in the French population (adults aged 18-74 years and children aged 3-17 years living in continental France in 2006-2007). The aim of this paper was to describe the distributions of total arsenic and the sum of iAs+MMA+DMA in the general adult population, and to present their main risk factors. In the arsenic study, 1500 and 1515 adults (requested to avoid seafood intake in the previous 3 days preceding urine collection) were included respectively for the analysis of the sum of inorganic arsenic (iAs) and its two metabolites, monomethylarsonic acid (MMA) and dimethylarsinic acid (DMA), and for the total arsenic. Results were presented as geometric means and selected percentiles of urinary arsenic concentrations (?g/L) and creatinine-adjusted urinary arsenic (?g/g of creatinine) for total arsenic, and the sum of inorganic arsenic and metabolites (iAs+MMA+DMA). The geometric mean concentration of the sum of iAs+MMA+DMA in the adult population living in France was 3.34 ?g/g of creatinine [3.23-3.45] (3.75 ?g/L [3.61-3.90]) with a 95th percentile of 8.9 ?g/g of creatinine (10.68 ?g/L). The geometric mean concentration of total arsenic was 11.96 ?g/g of creatinine [11.41-12.53] (13.42 ?g/L [12.77-14.09]) with a 95th percentile of 61.29 ?g/g of creatinine (72.75 ?g/L). Urinary concentrations of total arsenic and iAS+MMA+DMA were influenced by sociodemographic and economic factors, and by risk factors such as consumption of seafood products and of wine. In our study, covariate-adjusted geometric means demonstrated several slight differences, due to consumption of fish, shellfish/crustaceans or wine. This study provides the first reference value for arsenic in a representative sample of the French population not particularly exposed to high levels of arsenic (10 ?g/g of creatinine). It shows that urinary arsenic concentrations in the French adult population (in particular concentrations of iAs+MMA+DMA) were relatively low compared with foreign data. PMID:22796411

Saoudi, Abdessattar; Zeghnoun, Abdelkrim; Bidondo, Marie-Laure; Garnier, Robert; Cirimele, Vincent; Persoons, Renaud; Fréry, Nadine

2012-09-01

266

Oxyanion Concentrations in Eastern Sierra Nevada Rivers – 2. Arsenic and Phosphate  

Microsoft Academic Search

Water samples were collected from the Truckee River-Pyramid Lake system, the Walker River-Walker Lake system, and the Carson River, all located in eastern California and western Nevada, U.S.A., at three different times (i.e., summer 1991, spring 1992, and autumn 1992) over a two year period. The concentrations of As, Na, Cl, SPO4, and pH were measured in these river samples

Kevin H. Johannesson; W. Berry Lyons; Suey Huey; Georgia a. Doyle; Eric E. Swanson; Ed Hackett

1997-01-01

267

Influence of geology on arsenic concentrations in ground and surface water in central Lesvos, Greece.  

PubMed

The occurrence of As was studied in groundwater used for human consumption and irrigation, in stream water and sediments and in water from thermal springs in the drainage basin of Kalloni Gulf, island of Lesvos, Greece, in order to investigate the potential influence of the geothermal field of Polichnitos-Lisvori on the ground and surface water systems of the area. Total dissolved As varied in the range <0.7-88.3 microg L(-1) in groundwater, 41.1-90.7 microg L(-1) in thermal spring water and 0.4-13.2 microg L(-1) in stream water, whereas As concentrations in stream sediments varied between 2.0-21.9 mg kg(-1). Four out of 31 groundwater samples exceeded the EC standard of 10 microg L(-1). The survey revealed an enrichment in both surface and groundwater hydrological systems in the northern part of the area (average concentrations of As in groundwater, stream water and stream sediment: 8.0 microg L(-1), 8.8 microg L(-1) and 15.0 mg kg(-1) respectively), in association with the volcanic bedrocks, while lower As concentrations were found in the eastern part (average concentrations in groundwater, stream water and stream sediment: 2.9 microg L(-1), 1.7 microg L(-1) and 5.9 mg kg(-1) respectively), which is dominated by ophiolitic ultramafic formations. The variation of As levels between the different parts of the study area suggests that local geology exerts a determinant influence on As geochemical behaviour. On the other hand, the geothermal activity manifested in the area of Polichnitos-Lisvori does not affect the presence of As in groundwater and streams. PMID:18437513

Aloupi, Maria; Angelidis, Michael O; Gavriil, Apostolos M; Koulousaris, Michael; Varnavas, Soterios P

2009-04-01

268

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; Nřrregaard, Rikke; Hansen, Pernille B L; Marcher, Ann Britt; Frřkićr, Jřrgen; Mandrup, Susanne; Jensen, Boye L

2012-04-15

269

Intraindividual variability in arsenic methylation in a U.S. population.  

PubMed

Several recent investigations have reported associations between a reduced capacity to fully methylate inorganic arsenic and increased susceptibility to arsenic-caused cancer. In these studies, methylation patterns were based on a single assessment of urinary arsenic metabolites collected at the time of cancer diagnosis. However, the latency of arsenic-caused cancer may be several decades, and the extent to which a recent measurement can be used to estimate a person's past methylation pattern is unknown. In this investigation, the distribution of urinary inorganic arsenic, monomethylarsonate, and dimethylarsinate was used to assess intraindividual variation in methylation capacity in 81 subjects with low to moderate arsenic exposures. Multiple urine samples were collected from each subject over a 1-year period. Duplicate analyses done on 27 samples were used to assess laboratory measurement imprecision. The intraclass correlation coefficients (ICC) for the proportion of urinary arsenic as inorganic arsenic, monomethylarsonate, and dimethylarsinate in samples taken an average of 258 days apart, were 0.45 [95% confidence interval (95% CI), 0.23-0.63] 0.46 (95% CI, 0.24-0.64), and 0.49 (95% CI, 0.28-0.66). In analyses of duplicate samples, ICCs for the concentration of arsenic species ranged from 0.87 to 0.93, whereas ICCs for species proportions ranged from 0.63 to 0.76. These data suggest that individual methylation patterns remain fairly stable over time, although variability due to measurement imprecision or intraindividual changes over time does occur. This variability could lead to misclassification of methylation patterns and could bias relative risk estimates in studies of methylation and cancer towards the null. PMID:15824164

Steinmaus, Craig; Yuan, Yan; Kalman, Dave; Atallah, Raja; Smith, Allan H

2005-04-01

270

Arsenic Methyltransferase  

EPA Science Inventory

The metalloid arsenic enters the environment by natural processes (volcanic activity, weathering of rocks) and by human activity (mining, smelting, herbicides and pesticides). Although arsenic has been exploited for homicidal and suicidal purposes since antiquity, its significan...

271

Co-administration of meso 2,3-dimercaptosuccinic acid monoesters reduces arsenic concentration and oxidative stress in gallium arsenide exposed rats.  

PubMed

1. Gallium arsenide (GaAs), a semiconductor, exerts toxicity as a result of its constitutive moieties; that is, gallium and arsenic that becomes dissociated after exposure. The present study focuses on reducing arsenic concentration from the target organs using monoesters of meso 2,3-dimercaptosuccinic acid (DMSA) either individually or in combination. 2. Animals were exposed to GaAs (0.0014 mol/kg, orally for 8 weeks) and then treated with monoisoamyl DMSA (MiADMSA), monocyclohexyl DMSA (MchDMSA) or monomethyl DMSA (MmDMSA) either individually (0.3 mmol/kg, orally) or in combination (0.15 mmol/kg each, orally) for five consecutive days. 3. GaAs exposure significantly inhibited blood ?-aminolevulinic acid dehydrogenase (ALAD), suggesting alterations in the heme synthesis pathway. Whereas a significant increase in blood, liver and kidney reactive oxygen species accompanied by an increase in lipid peroxidation points to the involvement of oxidative stress in GaAs toxicity. 4. GaAs also significantly disturbed glutathione metabolism. Hepatic and renal catalase activity decreased significantly, whereas hepatic and renal superoxide dismutase activity, as well as serum transaminases activity, showed marginal increase. Treatment with MiADMSA in combination with MchDMSA showed better therapeutic efficacy compared with other treatments in the aforementioned variables. 5. Co-administration of MiADMSA with MchDMSA provided better therapeutic effects, including reduction of arsenic burden, compared with all other treatments. PMID:21501211

Flora, Swaran J S; Bhatt, Kapil; Dwivedi, Nidhi; Pachauri, Vidhu; Kushwah, Pramod K

2011-07-01

272

Sequential Determination of Total Arsenic and Cadmium in Concentrated Cadmium Sulphate Solutions by Flow-Through Stripping Chronopotentiometry after Online Cation Exchanger Separation  

PubMed Central

Flow-through stripping chronopotentiometry with a gold wire electrode was used for the determination of total arsenic and cadmium in cadmium sulphate solutions for cadmium production. The analysis is based on the online separation of arsenic as arsenate anion from cadmium cations by means of a cation exchanger. On measuring arsenate in the effluent, the trapped cadmium is eluted by sodium chloride solution and determined in a small segment of the effluent by making use of the same electrode. The elaborated protocol enables a full automatic measurement of both species in the same sample solution. The accuracy of the results was confirmed by atomic absorption spectrometry. The LOD and LOQ for Arsenic were found to be 0.9??g dm?3 and 2.7??g dm?3, respectively. A linear response range was observed in the concentration range of 1 to 300??g dm?3 for sample volumes of 4?mL. The repeatability and reproducibility were found to be 2.9% and 5.2%, respectively. The linear response range for cadmium was found to be 0.5 to 60?g/L. The method was tested on samples from a cadmium production plant.

Cacho, Frantisek; Lauko, Lukas; Manova, Alena; Dzurov, Jan; Beinrohr, Ernest

2012-01-01

273

Porphyrins - urine  

MedlinePLUS

Porphyrins help form many important substances in the body including hemoglobin, the protein in red blood cells that carries oxygen in the blood. Porphyrins can be found in urine. A urine porphyrins ...

274

Urine Metanephrines  

MedlinePLUS

... Urine Metanephrines, Total and Fractionated Related tests: Catecholamines , Plasma Free Metanephrines , VMA At a Glance Test Sample ... be ordered by itself or along with a plasma metanephrines test . Plasma and urine catecholamines testing may ...

275

Effect of organic matter amendment, arsenic amendment and water management regime on rice grain arsenic species.  

PubMed

Arsenic accumulation in rice grain has been identified as a major problem in some regions of Asia. A study was conducted to investigate the effect of increased organic matter in the soil on the release of arsenic into soil pore water and accumulation of arsenic species within rice grain. It was observed that high concentrations of soil arsenic and organic matter caused a reduction in plant growth and delayed flowering time. Total grain arsenic accumulation was higher in the plants grown in high soil arsenic in combination with high organic matter, with an increase in the percentage of organic arsenic species observed. The results indicate that the application of organic matter should be done with caution in paddy soils which have high soil arsenic, as this may lead to an increase in accumulation of arsenic within rice grains. Results also confirm that flooding conditions substantially increase grain arsenic. PMID:23466730

Norton, Gareth J; Adomako, Eureka E; Deacon, Claire M; Carey, Anne-Marie; Price, Adam H; Meharg, Andrew A

2013-06-01

276

Total arsenic in rice milk.  

PubMed

Rice milk and its by-products were tested for total arsenic concentration. Total arsenic concentration was determined using graphite-furnace atomic absorption spectrometry. The arsenic concentrations ranged from 2.7 ± 0.3 to 17.9 ± 0.5 µg L(-1). Rice milk and its by-products are not clearly defined as food, water or milk substitute. The US Environmental Protection Agency (EPA), the European Union (EU) and the World Health Organization (WHO) have set a level of 10 µg L(-1) for total arsenic concentrations in drinking water. The EU and the US regulatory agencies do not provide any guidelines on total arsenic concentrations in foods. This study provides us with a starting point to address this issue in the State of Mississippi, USA. PMID:24779982

Shannon, Ron; Rodriguez, Jose M

2014-03-01

277

ARSENIC REMOVAL  

EPA Science Inventory

Presentation covered five topics; arsenic chemistry, best available technology (BAT), surface water technology, ground water technology and case studies of arsenic removal. The discussion on arsenic chemistry focused on the need and method of speciation for AsIII and AsV. BAT me...

278

Modelling of arsenic retention in constructed wetlands.  

PubMed

A new model was developed in order to simulate the most significant arsenic retention processes that take place in constructed wetlands (CWs) treating high arsenic waters. The present contribution presents the implementation phases related to plants (arsenic uptake and accumulation, root arsenic adsorption, and root oxygen release), showing the first simulation results of the complete model. Different approaches with diverse influent configurations were simulated. In terms of total arsenic concentrations in effluent, the simulated data closely matched the data measured in all evaluated cases. The iron and arsenic species relationships, and the arsenic retention percentages obtained from simulations, were in agreement with the experimental data and literature. The arsenic retention efficiency increased whenever a new phase was implemented, reaching a maximum efficiency range of 85-95%. According to the quality of the obtained results, it can be considered that the implementation of all steps of RCB-ARSENIC provided reasonably good response values. PMID:23994963

Llorens, Esther; Obradors, Joshua; Alarcón-Herrera, María Teresa; Poch, Manel

2013-11-01

279

Differential DNA Methylation in Umbilical Cord Blood of Infants Exposed to Low Levels of Arsenic in Utero  

PubMed Central

Background: There is increasing epidemiologic evidence that arsenic exposure in utero, even at low levels found throughout much of the world, is associated with adverse reproductive outcomes and may contribute to long-term health effects. Animal models, in vitro studies, and human cancer data suggest that arsenic may induce epigenetic alterations, specifically by altering patterns of DNA methylation. Objectives: In this study we aimed to identify differences in DNA methylation in cord blood samples of infants with in utero, low-level arsenic exposure. Methods: DNA methylation of cord-blood derived DNA from 134 infants involved in a prospective birth cohort in New Hampshire was profiled using the Illumina Infinium Methylation450K array. In utero arsenic exposure was estimated using maternal urine samples collected at 24–28 weeks gestation. We used a novel cell mixture deconvolution methodology for examining the association between inferred white blood cell mixtures in infant cord blood and in utero arsenic exposure; we also examined the association between methylation at individual CpG loci and arsenic exposure levels. Results: We found an association between urinary inorganic arsenic concentration and the estimated proportion of CD8+ T lymphocytes (1.18; 95% CI: 0.12, 2.23). Among the top 100 CpG loci with the lowest p-values based on their association with urinary arsenic levels, there was a statistically significant enrichment of these loci in CpG islands (p = 0.009). Of those in CpG islands (n = 44), most (75%) exhibited higher methylation levels in the highest exposed group compared with the lowest exposed group. Also, several CpG loci exhibited a linear dose-dependent relationship between methylation and arsenic exposure. Conclusions: Our findings suggest that in utero exposure to low levels of arsenic may affect the epigenome. Long-term follow-up is planned to determine whether the observed changes are associated with health outcomes.

Koestler, Devin C.; Avissar-Whiting, Michele; Houseman, E. Andres; Karagas, Margaret R.

2013-01-01

280

Vitreous Fluid and/or Urine Glucose Concentrations in 1,335 Civil Aviation Accident Pilot Fatalities.  

National Technical Information Service (NTIS)

For aviation accident investigations at the Civil Aerospace Medical Institute (CAMI), vitreous fluid and urine samples from pilot fatalities are analyzed for glucose, and in those cases wherein glucose levels are elevated, blood hemoglobin A1c (HbA1c) is ...

A. K. Chaturvedi D. V. Canfield E. M. Forster S. R. Botch

2008-01-01

281

Selective leaching of arsenic and antimony from a tetrahedrite rich complex sulphide concentrate using alkaline sulphide solution  

Microsoft Academic Search

Removal of impurity elements in copper metallurgy is one of the major problems encountered today since pure copper ore reserves are becoming exhausted and the resources of unexploited ores often contain relatively high amounts of impurity elements like antimony, arsenic, mercury and bismuth, which need to be eliminated. The present work is aimed at pre-treating a tetrahedrite rich complex sulphide

Samuel A. Awe; Ĺke Sandström

2010-01-01

282

Concentrations of phenol, o-cresol, and 2,5-xylenol in the urine of workers employed in the distillation of the phenolic fraction of tar.  

PubMed Central

Phenol (87.3 mg/l), p-cresol (58.6 mg/l), o-cresol (76.9 mg/l), and 2,5-xylenol (36.7 mg/l) were detected in the urine of workers employed in the distillation of the high temperature phenolic fraction of tar (carbolic oil). The concentrations of these compounds in the urine of non-exposed male workers was 11.7 mg/l, 25.7 mg/l, 68.1 micrograms/l, and 69 micrograms/l respectively. The excretion rates were 4.20 mg/h for phenol, 2.4 mg/h for p-cresol, 3.3 mg/h for o-cresol; and 1.5 mg/h for 2,5-xylenol. The highest concentrations of the mentioned compounds were detected in urine collected between eight and 10 hours from the beginning of exposure. The kinetics of excretion are considered.

Bieniek, G

1994-01-01

283

Effect of a satiating meal on the concentrations of procolipase propeptide in the serum and urine of normal and morbidly obese subjects.  

PubMed Central

The effect of a satiating meal on the serum and urinary concentrations of procolipase propeptide (Ala-Pro-Gly-Pro-Arg, APGPR) immunoreactivity, as measured by enzyme linked immunosorbent assay (ELISA) specific for free APGPR, has been studied in normal and morbidly obese human subjects. The normal subjects displayed a biphasic response with coordinate increases in both serum and urine APGPR immunoreactivity both occurring within the first two hours after the meal. In two of three of the morbidly obese subjects, this early rise in APGPR concentration in urine was not seen but was followed by a slow rise in urinary APGPR immunoreactivity at four to six hours. In both the normal and obese groups, the urinary immunoreactive signal was found to coelute with synthetic APGPR on gel chromatography. In rats, procolipase propeptide (Val-Pro-Asp-Pro-Arg, VPDPR) specifically inhibits fat intake early in the postprandial period when given peripherally or centrally. This study suggests that in humans APGPR reaches the circulation shortly after feeding and is excreted in the urine. These findings are consistent with the hypothesis that human procolipase propeptide may also act as a satiety signal. In addition the late appearance of the peptide in some of the morbidly obese patients could be associated with perturbation of appetite control in these subjects.

Bowyer, R C; Rowston, W M; Jehanli, A M; Lacey, J H; Hermon-Taylor, J

1993-01-01

284

Evaluation of arsenic speciation in rainbow trout and fathead minnows from dietary exposure  

EPA Science Inventory

The concentration of total arsenic and various arsenic species were measured in food and fish tissue samples from two dietary arsenic exposures to juvenile fish. For arsenic speciation, samples were extracted with 10% MeOH and analyzed by HPLC/ICPMS. Total arsenic concentration...

285

Arsenic occurrence in New Hampshire drinking water  

SciTech Connect

Arsenic concentrations were measured in 992 drinking water samples collected from New Hampshire households using online hydride generation ICP-MS. These randomly selected household water samples contain much less arsenic than those voluntarily submitted for analysis to the New Hampshire Department of Environmental Services (NHDES). Extrapolation of the voluntarily submitted sample set to all New Hampshire residents significantly overestimates arsenic exposure. In randomly selected households, concentrations ranged from <0.0003 to 180 {micro}g/L, with water from domestic wells containing significantly more arsenic than water from municipal sources. Water samples from drilled bedrock wells had the highest arsenic concentrations, while samples from surficial wells had the lowest arsenic concentrations. The authors suggest that much of the groundwater arsenic in New Hampshire is derived from weathering of bedrock materials and not from anthropogenic contamination. The spatial distribution of elevated arsenic concentrations correlates with Late-Devonian Concord-type granitic bedrock. Field observations in the region exhibiting the highest groundwater arsenic concentrations revealed abundant pegmatite dikes associated with nearby granites. Analysis of rock digests indicates arsenic concentrations up to 60 mg/kg in pegmatites, with much lower values in surrounding schists and granites. Weak acid leaches show that approximately half of the total arsenic in the pegmatites is labile and therefore can be mobilized during rock-water interaction.

Peters, S.C.; Blum, J.D.; Klaue, B. [Dartmouth Coll., Hanover, NH (United States). Dept. of Earth Sciences] [Dartmouth Coll., Hanover, NH (United States). Dept. of Earth Sciences; Karagas, M.R. [Dartmouth Medical School, Hanover, NH (United States). Dept. of Community and Family Medicine] [Dartmouth Medical School, Hanover, NH (United States). Dept. of Community and Family Medicine

1999-05-01

286

Urine Pretreat Injection System  

NASA Technical Reports Server (NTRS)

A new method of introducing the OXONE (Registered Trademark) Monopersulfate Compound for urine pretreat into a two-phase urine/air flow stream has been successfully tested and evaluated. The feasibility of this innovative method has been established for purposes of providing a simple, convenient, and safe method of handling a chemical pretreat required for urine processing in a microgravity space environment. Also, the Oxone portion of the urine pretreat has demonstrated the following advantages during real time collection of 750 pounds of urine in a Space Station design two-phase urine Fan/Separator: Eliminated urine precipitate buildup on internal hardware and plumbing; Minimized odor from collected urine; and Virtually eliminated airborne bacteria. The urine pretreat, as presently defined for the Space Station program for proper downstream processing of urine, is a two-part chemical treatment of 5.0 grams of Oxone and 2.3 ml of H2SO4 per liter of urine. This study program and test demonstrated only the addition of the proper ratio of Oxone into the urine collection system upstream of the Fan/Separator. This program was divided into the following three major tasks: (1) A trade study, to define and recommend the type of Oxone injection method to pursue further; (2) The design and fabrication of the selected method; and (3) A test program using high fidelity hardware and fresh urine to demonstrate the method feasibility. The trade study was conducted which included defining several methods for injecting Oxone in different forms into a urine system. Oxone was considered in a liquid, solid, paste and powered form. The trade study and the resulting recommendation were presented at a trade study review held at Hamilton Standard on 24-25 October 94. An agreement was reached at the meeting to continue the solid tablet in a bag concept which included a series of tablets suspended in the urine/air flow stream. These Oxone tablets would slowly dissolve at a controlled rate providing the proper concentration in the collected urine. To implement the solid tablet in a bag approach, a design concept was completed with prototype drawings of the complete urine pretreat prefilter assembly. A successful fabrication technique was developed for retaining the Oxone tablets in a fabric casing attached to the end of the existing Space Station Waste Collection System urine prefilter assembly. The final pretreat prefilter configuration held sufficient Oxone in a tablet form to allow normal scheduled daily (or twice daily) change out of the urine filter depending on the use rate of the Space Station urine collection system. The actual tests to prove the concept were conducted using the Urine Fan/Separator assembly that was originally used in the STS-52 Design Test Objective (DTO) urinal assembly. Other related tests were conducted to demonstrate the actual minimum ratio of Oxone to urine that will control microbial growth.

1995-01-01

287

Sorption on natural solids for arsenic removal  

Microsoft Academic Search

Steady state experiments were conducted on arsenic sorption from aqueous solutions by natural solids to test the feasibility of these materials to act as concentrator for arsenic removal from groundwater and drinking water. The solids considered were natural zeolites, volcanic stone, and the cactaceous powder CACMM. The arsenic species studied were As(III), As(V), dimethylarsinic acid (DMA) and phenylarsonic acid (PHA).

M. P. Elizalde-González; J. Mattusch; W.-D. Einicke; R. Wennrich

2001-01-01

288

Arsenic mobility and stabilization in topsoils  

Microsoft Academic Search

Agricultural topsoil can be polluted with arsenic due to irrigation with contaminated water from geothermal sources. This work evaluates the mobility of arsenic in topsoils and stabilization of arsenic with zero valent iron (ZVI), in short term experiments. The objective of this study was the development of a simplified empirical model that can predict the concentration of iron released from

Konstantina Tyrovola; Nikolaos P. Nikolaidis

2009-01-01

289

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

290

Assessing the Measurement Precision of Various Arsenic Forms and Arsenic Exposure in the National Human Exposure Assessment Survey (NHEXAS)  

PubMed Central

Archived samples collected from 1995 to 1997 in the National Human Exposure Assessment Survey (NHEXAS) in U.S. Environmental Protection Agency Region 5 (R5) and the Children’s Study (CS) in Minnesota were analyzed for total arsenic, arsenate [As(V)], arsenite, dimethyl arsenic acid (DMA), monomethyl arsenic acid (MMA), arsenobetaine (AsB), and arsenocholine. Samples for the CS included drinking water, urine, hair, and dust; both studies included food (duplicate plate, composited 4-day food samples from participants). Except for AsB and As(V), the levels for As species measured in the food and drinking water samples were very low or nonexistent. The analytical methods used for measuring As species were sensitive to < 1 ppb. During the analysis of food and drinking water samples, chromatographic peaks appeared that contained As, but they did not correspond to those being quantified. Thus, in some samples, the sum of the individual As species levels was less than the total As level measured because the unknown forms of As were not quantified. On the other hand, total As was detectable in almost all samples (>90%) except for hair (47%), indicating that the analytical method was sufficiently sensitive. Population distributions of As concentrations measured in drinking water, food (duplicate plate), dust, urine, and hair were estimated. Exposures to total As in food for children in the CS were about twice as high as in the general R5 population (medians of 17.5 ppb and 7.72 ppb, respectively). In addition, AsB was the most frequently detected form of As in food eaten by the participants, while As(V) was only rarely detected. Thus, the predominant dietary exposure was from an organic form of As. The major form of As in drinking water was As(V). Spearman (rank) correlations and Pearson (log-concentration scale) correlations between the biomarkers (urine, hair) and the other measures (food, drinking water, dust) and urine versus hair were performed. In the NHEXAS CS, total As and AsB in the food eaten were significantly correlated with their levels in urine. Also, levels of As(V) in drinking water correlated with DMA and MMA in urine. Arsenic levels in dust did not show a relationship with urine or hair levels, and no relationship was observed for food, drinking water, and dust with hair. Urine samples were collected on days 3, 5, and 7 of participants’ monitoring periods. Total As levels in urine were significantly associated across the three pairwise combinations—i.e., day 3 versus day 5, day 3 versus day 7, and day 5 versus day 7. Because the half-life of As in the body is approximately 3 days, this suggests that some exposure occurred continually from day to day. This trend was also observed for AsB, suggesting that food is primarily responsible for the continual exposure. DMA and MMA in urine were also significantly correlated but not in all combinations.

Pellizzari, Edo D.; Clayton, C. Andrew

2006-01-01

291

Arsenic removal from aqueous solutions by adsorption on laterite soil  

Microsoft Academic Search

Laterite soil was used as an adsorbent for arsenic removal from contaminated groundwater. Effects of pH, adsorbent dose, adsorbent size, contact time, initial arsenic concentration and presence of interfering species on arsenic removal were found out. Laterite soil was found to be very effective for arsenic adsorption. It was found that 4 h contact time was sufficient for ? 98%

Sanjoy K. Maji; Anjali Pal; Tarasankar Pal

2007-01-01

292

REMOVING ARSENIC FROM DRINKING WATER  

EPA Science Inventory

Pilot-plant tests of two treatment methods-activated alumina and ion exchange--for removing arsenic from drinking water were evaluated at the Fallon, Nev., Naval Air Station (NAS). The arsenic concentration was 0.080-0.116 mg/L, exceeding the 0.05-mg/L maximum contaminant level. ...

293

Environmental concentrations of copper, chromium, and arsenic released from a chromated-copper-arsenate- (CCA-C-) treated wetland boardwalk  

Microsoft Academic Search

A study was conducted to evaluate environmental accumulation and mobility of total copper, chromium, and arsenic adjacent to a chromated-copper-arsenate- (CCA-C-) treated wetland boardwalk. The study was considered a severe test because it included a large volume of treated wood in a site with high annual rainfall. Soil and sediment samples were collected before construction and 0.5, 2, 5.5, 11,

Stan Lebow; Daniel Foster

294

Consumption of folate-related nutrients and metabolism of arsenic in Bangladesh13  

Microsoft Academic Search

Background: Inorganic arsenic (InAs) is metabolized to mono- methylarsonic acid (MMA) and dimethylarsinic acid (DMA), and this methylation facilitates urinary arsenic excretion. Previous studies suggest that persons with more complete methylation, characterized as greater proportions of DMA and lesser proportions of MMA and InAs in urine, have a lower risk of adverse arsenic- related health outcomes. Objective: The purpose of

Julia E Heck; Mary V Gamble; Yu Chen; Joseph H Graziano; Vesna Slavkovich; Faruque Parvez; John A Baron; Geoffrey R Howe; Habibul Ahsan

295

Urine Tests (For Parents)  

MedlinePLUS

... If either the urine dipstick test or the microscopic test shows white blood cells, red blood cells, ... ON THIS TOPIC Urine Test: Calcium Urine Test: Protein Urine Test: Routine Culture Urine Test: Creatinine Urine ...

296

Arsenic, Cadmium, Lead, and Mercury in Sweat: A Systematic Review  

PubMed Central

Arsenic, cadmium, lead, and mercury exposures are ubiquitous. These toxic elements have no physiological benefits, engendering interest in minimizing body burden. The physiological process of sweating has long been regarded as “cleansing” and of low risk. Reports of toxicant levels in sweat were sought in Medline, Embase, Toxline, Biosis, and AMED as well as reference lists and grey literature, from inception to March 22, 2011. Of 122 records identified, 24 were included in evidence synthesis. Populations, and sweat collection methods and concentrations varied widely. In individuals with higher exposure or body burden, sweat generally exceeded plasma or urine concentrations, and dermal could match or surpass urinary daily excretion. Arsenic dermal excretion was severalfold higher in arsenic-exposed individuals than in unexposed controls. Cadmium was more concentrated in sweat than in blood plasma. Sweat lead was associated with high-molecular-weight molecules, and in an interventional study, levels were higher with endurance compared with intensive exercise. Mercury levels normalized with repeated saunas in a case report. Sweating deserves consideration for toxic element detoxification. Research including appropriately sized trials is needed to establish safe, effective therapeutic protocols.

Sears, Margaret E.; Kerr, Kathleen J.; Bray, Riina I.

2012-01-01

297

N-6-Adenine-Specific DNA Methyltransferase 1 (N6AMT1) Polymorphisms and Arsenic Methylation in Andean Women  

PubMed Central

Background: In humans, inorganic arsenic is metabolized to methylated metabolites mainly by arsenic (+3 oxidation state) methyltransferase (AS3MT). AS3MT polymorphisms are associated with arsenic metabolism efficiency. Recently, a putative N-6-adenine-specific DNA methyltransferase 1 (N6AMT1) was found to methylate arsenic in vitro. Objective: We evaluated the role of N6AMT1 polymorphisms in arsenic methylation efficiency in humans. Methods: We assessed arsenic methylation efficiency in 188 women exposed to arsenic via drinking water (~ 200 µg/L) in the Argentinean Andes by measuring the relative concentrations of arsenic metabolites in urine [inorganic arsenic, methylarsonic acid (MMA), and dimethylarsinic acid] by high-performance liquid chromatography coupled with hydride generation and inductively coupled plasma mass spectrometry. We performed genotyping for N6AMT1 and AS3MT polymorphisms by Taqman assays, and gene expression (in blood; n = 63) with Illumina HumanHT-12 v4.0. Results: Five N6AMT1 single nucleotide polymorphisms (SNPs; rs1997605, rs2205449, rs2705671, rs16983411, and rs1048546) and two N6AMT1 haplotypes were significantly associated with the percentage of MMA (%MMA) in urine, even after adjusting for AS3MT haplotype. %MMA increased monotonically according to the number of alleles for each SNP (e.g., for rs1048546, mean %MMA was 7.5% for GG, 8.8% for GT, and 9.7% for TT carriers). Three SNPs were in linkage disequilibrium (R2 > 0.8). Estimated associations for joint effects of N6AMT1 (haplotype 1) and AS3MT (haplotype 2) were generally consistent with expectations for additive effects of each haplotype on %MMA. Carriers of N6AMT1 genotypes associated with lower %MMA showed the lowest N6AMT1 expression, but associations were monotonic according to copy number for only one genotype and one haplotype. Conclusions: N6AMT1 polymorphisms were associated with arsenic methylation in Andean women, independent of AS3MT. N6AMT1 polymorphisms may be susceptibility markers for arsenic-related toxic effects.

Harari, Florencia; Engstrom, Karin; Concha, Gabriela; Colque, Graciela; Vahter, Marie

2013-01-01

298

Performance and mechanism of arsenic removal from water by a nanofiltration membrane  

Microsoft Academic Search

The removal of arsenic by a commercial nanofiltration membrane was evaluated with respect to the performance and mechanism. The important membrane properties governing the separation of arsenic, such as molecular weight cut-off (MWCO), electrokinetic charge and individual salts rejection characteristics, were determined. The mechanisms of arsenic rejection were directly investigated by measuring the effects of the initial arsenic concentration, arsenic

Cuong Manh Nguyen; Sunbaek Bang; Jaeweon Cho; Kyoung-Woong Kim

2009-01-01

299

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

2013-06-01

300

Arsenic Contamination in Food-chain: Transfer of Arsenic into Food Materials through Groundwater Irrigation  

PubMed Central

Arsenic contamination in groundwater in Bangladesh has become an additional concern vis-ŕ-vis its use for irrigation purposes. Even if arsenic-safe drinking-water is assured, the question of irrigating soils with arsenic-laden groundwater will continue for years to come. Immediate attention should be given to assess the possibility of accumulating arsenic in soils through irrigation-water and its subsequent entry into the food-chain through various food crops and fodders. With this possibility in mind, arsenic content of 2,500 water, soil and vegetable samples from arsenic-affected and arsenic-unaffected areas were analyzed during 1999–2004. Other sources of foods and fodders were also analyzed. Irrigating a rice field with groundwater containing 0.55 mg/L of arsenic with a water requirement of 1,000 mm results in an estimated addition of 5.5 kg of arsenic per ha per annum. Concentration of arsenic as high as 80 mg per kg of soil was found in an area receiving arsenic-contaminated irrigation. A comparison of results from affected and unaffected areas revealed that some commonly-grown vegetables, which would usually be suitable as good sources of nourishment, accumulate substantially-elevated amounts of arsenic. For example, more than 150 mg/kg of arsenic has been found to be accumulated in arum (kochu) vegetable. Implications of arsenic ingested in vegetables and other food materials are discussed in the paper.

Joardar, J.C.; Parvin, S.; Correll, Ray; Naidu, Ravi

2006-01-01

301

Digital spatial data for observed, predicted, and misclassification errors for observations in the training dataset for nitrate and arsenic concentrations in basin-fill aquifers in the Southwest Principal Aquifers study area  

USGS Publications Warehouse

This product "Digital spatial data for observed, predicted, and misclassification errors for observations in the training dataset for nitrate and arsenic concentrations in basin-fill aquifers in the Southwest Principal Aquifers study area" is a 1:250,000-scale point spatial dataset developed as part of a regional Southwest Principal Aquifers (SWPA) study (Anning and others, 2012). The study examined the vulnerability of basin-fill aquifers in the southwestern United States to nitrate contamination and arsenic enrichment. Statistical models were developed by using the random forest classifier algorithm to predict concentrations of nitrate and arsenic across a model grid that represents local- and basin-scale measures of source, aquifer susceptibility, and geochemical conditions.

McKinney, Tim S.; Anning, David W.

2012-01-01

302

Quantitative imaging of arsenic and its species in goat following long term oral exposure.  

PubMed

Severity of arsenic toxicity was reported to vary depending on its species. The present study reflects the status of different species of arsenic in goat following long-term exposure of arsenic leading to hepatic damage. The experiment was conducted with six black Bengal goats, which were administered with sodium arsenite orally at a dose rate of 2 mgkg(-1) daily for 84 days. Faeces, urine, hair and blood samples were collected from those animals at 14 days interval. Excretion of total arsenic was reduced from 56 days onwards through both faeces and urine indicating higher accumulation of arsenic in body. The speciation study revealed that urinary arsenic was mainly of organic type, whereas hair accumulated almost equal proportion of arsenite, arsenate and organo arsenicals. Goats excreted high proportion of organo arsenicals through faeces possibly due to hepatobiliary secretion of organo arsenic into the gut. Significantly elevated serum alanine aminotransferase and aspartate aminotransferase activities (p<0.05) along with histopathological changes in liver indicated hepatotoxicity. The arsenite fraction increased and organic proportion decreased in urine as the time progressed, which indicates that arsenite gets methylated in liver of goat. The study thus alluded that the toxicity of arsenic would aggravate if the animals were exposed for long time as the hepatotoxicity progressed resulting in decreased methylation and formation of organo arsenicals and decreased excretions through urine. PMID:22497900

Patra, Pabitra Hriday; Bandyopadhyay, Samiran; Kumar, Rakesh; Datta, Bakul Kumar; Maji, Chinmoy; Biswas, Suman; Dash, Jeevan Ranjan; Sar, Tapas Kumar; Sarkar, Samar; Manna, Sanjib K; Chakraborty, Animesh Kumar; Mandal, Tapan Kumar

2012-06-01

303

Cotinine concentrations in amniotic fluid and urine of smoking, passive smoking and non-smoking pregnant women at term and in the urine of their neonates on 1st day of life  

Microsoft Academic Search

Cotinine was measured in the amniotic fluid and urine of 31 pregnant women and in the urine of their offspring. Amniotic fluid cotinine was 8 times higher in active and 2.5 times higher in passive smokers than in non-smokers. In general, amniotic fluid cotinine was considerably higher than urinary cotinine both in active and in passive smokers. Estimation of cotinine

J. S. Jordanov; Dimiter Nestorov

1990-01-01

304

Arsenic contamination in groundwater of Samta, Bangladesh.  

PubMed

In March 1997, we analyzed the water of all tubewells used for drinking in Samta village in the Jessore district, Bangladesh. It has been confirmed from the survey that the arsenic contamination in Samta was one of the worst in the Ganges basin including West Bengal, India. 90% of the tubewells had arsenic concentrations above the Bangladesh standard of 0.05 mg/l. Tubewells with higher arsenic concentrations of over 0.50 mg/l were distributed in the southern area with a belt-like shape from east to west, and the distribution of arsenic concentration showed gradual decreasing toward northern area of the village. In order to examine the characteristics of the arsenic distribution in Samta, we have performed investigations such as: 1) the characteristics of groundwater flow, 2) the distribution of arsenic in the ground, 3) the concentration of arsenic and the other dissolved materials in groundwater, and 4) the distribution of arsenic concentration of trivalence and pentavalence. This paper examines the mechanism of arsenic release to groundwater and explains the above-mentioned characteristics of the arsenic contamination in Samta through the investigations of the survey results for these years. PMID:12523781

Yokota, H; Tanabe, K; Sezaki, M; Yano, Y; Hamabe, K; Yabuuchi, K; Tokunaga, H

2002-01-01

305

Evaluation of Exposure to Arsenic in Residential Soil  

SciTech Connect

In response to concerns regarding arsenic in soil from a pesticide manufacturing plant, we conducted a biomonitoring study on children younger than 7 years of age, the age category of children most exposed to soil. Urine samples from 77 children (47% participation rate) were analyzed for total arsenic and arsenic species related to ingestion of inorganic arsenic. Older individuals also provided urine (n = 362) and toenail (n = 67) samples. Speciated urinary arsenic levels were similar between children (geometric mean, geometric SD, and range: 4.0, 2.2, and 0.89?17.7 ?g/L, respectively) and older participants (3.8, 1.9, 0.91?19.9 ?g/L) and consistent with unexposed populations. Toenail samples were < 1 mg/kg. Correlations between speciated urinary arsenic and arsenic in soil (r = 0.137, p = 0.39; n = 41) or house dust (r = 0.049, p = 0.73; n = 52) were not significant for children. Similarly, questionnaire responses indicating soil exposure were not associated with increased urinary arsenic levels. Relatively low soil arsenic exposure likely precluded quantification of arsenic exposure above background.

Tsuji, Joyce S.; Van Kerkhove, Maria D.; Kaetzel, Rhonda; Scrafford, Carolyn; Mink, Pamela; Barraj, Leila M.; Crecelius, Eric A.; Goodman, Michael

2005-12-01

306

Determination of As, Cd, Pb, and Hg in urine using inductively coupled plasma mass spectrometry with the direct injection high efficiency nebulizer  

Microsoft Academic Search

The application of the large-bore direct injection high efficiency nebulizer (LB-DIHEN) for the determination of arsenic (As), cadmium (Cd), lead (Pb), and mercury (Hg) in urine by inductively coupled plasma mass spectrometry (ICP-MS) is described. The LB-DIHEN is compared with the standard method using a concentric pneumatic nebulizer and cyclonic spray chamber. In addition to the toxicological significance of As,

Michael G. Minnich; Derek C. Miller; Patrick J. Parsons

2008-01-01

307

Arsenic, Anaerobes, and Astrobiology  

NASA Astrophysics Data System (ADS)

Arsenic is an element best known for its highly poisonous nature, so it is not something one would associate with being a well-spring for life. Yet discoveries made over the past two decades have delineated that not only are some microbes resistant to arsenic, but that this element's primary redox states can be exploited to conserve energy and support prokaryotic growth ('arsenotrophy') in the absence of oxygen. Hence, arsenite [As(III)] can serve as an electron donor for chemo- or photo-autotrophy while arsenate [As(V)] will serve as an electron acceptor for chemo-heterotrophs and chemo-autotrophs. The phylogenetic diversity of these microbes is broad, encompassing many individual species from diverse taxonomic groups in the Domain Bacteria, with fewer representatives in the Domain Archaea. Speculation with regard to the evolutionary origins of the key functional genes in anaerobic arsenic transformations (arrA and arxA) and aerobic oxidation (aioB) has led to a disputation as to which gene and function is the most ancient and whether arsenic metabolism extended back into the Archaean. Regardless of its origin, robust arsenic metabolism has been documented in extreme environments that are rich in their arsenic content, such as hot springs and especially hypersaline soda lakes associated with volcanic regions. Searles Lake, CA is an extreme, salt-saturated end member where vigorous arsenic metabolism occurs, but there is no detectable sulfate-reduction or methanogenesis. The latter processes are too weak bio-energetically to survive as compared with arsenotrophy, and are also highly sensitive to the abundance of borate ions present in these locales. These observations have implications with respect to the search for microbial life elsewhere in the Solar System where volcanic-like processes have been operative. Hence, because of the likelihood of encountering dense brines in the regolith of Mars (formed by evapo-concentration) or beneath the ice layers of Europa, Ganymede, Titan or Enceladus (formed by cryo-concentration), arsenotrophy could serve as a credible means of microbial energy conservation. Regrettably, the direct search for arsenic biomarkers is restricted because only one stable isotope exists (75As), which rules out the use of stable isotopic ratios in this regard. However, antimony oxyanions often co-occur with arsenic in the environment. Its two stable isotopes (123Sb and 121Sb) hold the potential to be exploited as a proxy isotopic biomarker for the fingerprint of microbial arsenotrophy. Whether such an approach is feasible needs to be investigated.

Stolz, J. F.; Oremland, R. S.; Switzer Blum, J.; Hoeft, S. E.; Baesman, S. M.; Bennett, S.; Miller, L. G.; Kulp, T. R.; Saltikov, C.

2013-12-01

308

A Phytoremediation Strategy for Arsenic  

SciTech Connect

A Phytoremediation Strategy for Arsenic Progress Report May, 2005 Richard B. Meagher Principal Investigator Arsenic pollution affects the health of several hundred millions of people world wide, and an estimated 10 million Americans have unsafe levels of arsenic in their drinking water. However, few environmentally sound remedies for cleaning up arsenic contaminated soil and water have been proposed. Phytoremediation, the use of plants to extract and sequester environmental pollutants, is one new technology that offers an ecologically sound solution to a devastating problem. We propose that it is less disruptive to the environment to harvest and dispose of several thousand pounds per acre of contaminated aboveground plant material, than to excavate and dispose of 1 to 5 million pounds of contaminated soil per acre (assumes contamination runs 3 ft deep). Our objective is to develop a genetics-based phytoremediation strategy for arsenic removal that can be used in any plant species. This strategy requires the enhanced expression of several transgenes from diverse sources. Our working hypothesis is that organ-specific expression of several genes controlling the transport, electrochemical state, and binding of arsenic will result in the efficient extraction and hyperaccumulation of arsenic into aboveground plant tissues. This hypothesis is supported by theoretical arguments and strong preliminary data. We proposed six Specific Aims focused on testing and developing this arsenic phytoremediation strategy. During the first 18 months of the grant we made significant progress on five Specific Aims and began work on the sixth as summarized below. Specific Aim 1: Enhance plant arsenic resistance and greatly expand sinks for arsenite by expressing elevated levels of thiol-rich, arsenic-binding peptides. Hyperaccumulation of arsenic depends upon making plants that are both highly tolerant to arsenic and that have the capacity to store large amounts of arsenic aboveground. Phytochelatins bind diverse thiol-reactive elements like As(III) and are synthesized from amino acids in a three-step enzymatic pathway utilizing three enzymes: ECS = gamma-glutamylcysteine synthetase; GS = GSH synthetase; and PS = phytochelatin synthase. We cloned each of the genes that encode these enzymes and used at least two different plant promoters to express them in transgenic Arabidopsis. We have shown that all three confer significant resistance to arsenic and allow rapid growth on a concentration of arsenic (300 micromolar) that kills wild-type seeds and plants.

Meagher, Richard B.

2005-06-01

309

Test of environmental exposure to arsenic and hearing changes in exposed children  

PubMed Central

Arsenic determination was carried out on hair, urine, and blood samples taken from groups of 10-year-old boys, each numbering 20 to 25 individuals, residing in a region polluted by arsenic. In all the examined materials considerably elevated concentrations of arsenic were found. The relation of the observed levels of arsenic to the distance of the place of residence up to a distance of more than 30 km from the source of the emissions was studied. On the basis of the results obtained, the most advantageous material for estimation of nonoccupational exposure to arsenic seems to be hair, in spite of some problems with the decontamination procedure involved. Considerable variability among individual arsenic values in the hair makes group examination a necessity. Hearing changes were analyzed in a group of 56 10-year old children residing near a power plant burning local coal of high arsenic content. The results of both audiometric and clinical examination were compared with those of control group numbering 51 children of the same age living outside the polluted area. The highly standardized audiometric and clinical examination were completed with a questionnaire analysis concerning the personal medical histories of the children. The obtained data were elaborated statistically by means of the ?2– test. In the case of air conduction, important hearing losses were found at frequencies of 125, 250 and 8000 Hz, especially at the lowest frequency range. Significant degrees of hearing loss were found in bone conduction as well as in the corresponding ranges of frequencies. The high statistical significance of the hearing impairments found points to very low probability of their being only an “accidental” finding. The possibility of toxic damage to the ear cannot yet be excluded.

Bencko, V.; Symon, K.

1977-01-01

310

Use of albumin creatinine ratio and urine albumin concentration as a screening test for albuminuria in an Indo-Asian population  

Microsoft Academic Search

Background. Albuminuria (>30 mg\\/day) based on 24 h urine albumin excretion is one of the criteria for chronic kidney disease (CKD) and a predictor of cardiovascular disease (CVD). Differences in urine albumin concentra- tion and creatinine excretion rates between Indo-Asians and other populations may require different threshold values for detection of albuminuria. We compared the use of spot urine albumin

Tazeen H. Jafar; Nish Chaturvedi; Juanita Hatcher; Andrew S. Levey

2007-01-01

311

Novel DFO-functionalized mesoporous silica for iron sensing. Part 2. Experimental detection of free iron concentration (pFe) in urine samples.  

PubMed

Successful in vivo chelation treatment of iron(iii) overload pathologies requires that a significant fraction of the administered drug actually chelates the toxic metal. Increased mobilization of the iron(iii) in experiments on animals or humans, most often evaluated from urinary output, is usually used as an assessment tool for chelation therapy. Alternatively, the efficiency of a drug is estimated by calculating the complexing ability of a chelating agent towards Fe(iii). The latter is calculated by the pFe value, defined as the negative logarithm of the concentration of the free metal ion in a solution containing 10 ?M total ligand and 1 ?M total metal at a physiological pH of 7.4. In theory, pFe has to be calculated taking into account all the complexation equilibria involving the metal and the possible ligands. Nevertheless, complexation reactions in complex systems such as serum and urine may hardly be accurately modelled by computer software. The experimental determination of the bioavailable fraction of iron(iii) in biological fluids would therefore be of the utmost relevance in the clinical practice. The efficiency of the therapy could be more easily estimated as well as the course of overload pathologies. In this context, the aim of the present work was the development of a sensor to assess the free iron directly in biological fluids (urine) of patients under treatment with chelating agents. In the proposed device (DFO-MS), the strong iron chelator deferoxamine (DFO) is immobilized on the MCM-41 mesoporous silica. The characterization of the iron(iii) sorption on DFO-MS was undertaken, firstly in 0.1 M KNO3, then directly in urine samples, in order to identify the sorption mechanism. The stoichiometry of the reaction in the solid phase was found to be: with an exchange constant (average value) of log??ex = 40(1). The application of DFO-MS to assess pFe in SPU (Simulating Pathology Urine) samples was also considered. The results obtained were very promising for a future validation and subsequent application of the sensor in samples of patients undergoing chelation therapy. PMID:24883429

Alberti, Giancarla; Emma, Giovanni; Colleoni, Roberta; Pesavento, Maria; Nurchi, Valeria Marina; Biesuz, Raffaela

2014-07-14

312

Urine Preservative  

NASA Technical Reports Server (NTRS)

Disclosed is CPG, a combination of a chlorhexidine salt (such as chlorhexidine digluconate, chlorhexidine diacetate, or chlorhexidine dichloride) and n-propyl gallate that can be used at ambient temperatures as a urine preservative.

Smith, Scott M. (Inventor); Nillen, Jeannie (Inventor)

2001-01-01

313

Digital Spatial Data for Observed, Predicted, and Misclassification errors for Observations in the Training Dataset for Nitrate and Arsenic Concentrations in Basin-Fill Aquifers in the Southwest Principal Aquifers Study Area.  

National Technical Information Service (NTIS)

This product Digital spatial data for observed, predicted, and misclassification errors for observations in the training dataset for nitrate and arsenic concentrations in basin-fill aquifers in the Southwest Principal Aquifers study area is a 1:250,000-sc...

D. W. Anning T. S. McKinney

2012-01-01

314

Arsenic: The Silent Killer  

SciTech Connect

Andrea Foster uses x-rays to determine the forms of potentially toxic elements in environmentally-important matrices such as water, sediments, plants, and microorganisms. In this free public lecture, Foster will discuss her research on arsenic, which is called the silent killer because dissolved in water, it is colorless, odorless, and tasteless, yet consumption of relatively small doses of this element in its most toxic forms can cause rapid and violent death. Arsenic is a well-known poison, and has been used as such since ancient times. Less well known is the fact that much lower doses of the element, consumed over years, can lead to a variety of skin and internal cancers that can also be fatal. Currently, what has been called the largest mass poisoning in history is occurring in Bangladesh, where most people are by necessity drinking ground water that is contaminated with arsenic far in excess of the maximum amounts determined to be safe by the World Health Organization. This presentation will review the long and complicated history with arsenic, describe how x-rays have helped explain the high yet spatially variable arsenic concentrations in Bangladesh, discuss the ways in which land use in Bangladesh may be exacerbating the problem, and summarize the impact of this silent killer on drinking water systems worldwide.

Foster, Andrea (USGS) [USGS

2006-02-28

315

Arsenic uptake by Lemna minor in hydroponic system.  

PubMed

Arsenic is hazardous and causes several ill effects on human beings. Phytoremediation is the use of aquatic plants for the removal of toxic pollutants from external media. In the present research work, the removal efficiency as well as the arsenic uptake capacity of duckweed Lemna minor has been studied. Arsenic concentration in water samples and plant biomass were determined by AAS. The relative growth factor of Lemna minor was determined. The duckweed had potential to remove as well as uptake arsenic from the aqueous medium. Maximum removal of more than 70% arsenic was achieved atinitial concentration of 0.5 mg/1 arsenic on 15th day of experimental period of 22 days. Removal percentage was found to decrease with the increase in initial concentration. From BCF value, Lemna minor was found to be a hyperaccumulator of arsenic at initial concentration of 0.5 mg/L, such that accumulation decreased with increase in initial arsenic concentration. PMID:24933913

Goswami, Chandrima; Majumder, Arunabha; Misra, Amal Kanti; Bandyopadhyay, Kaushik

2014-01-01

316

Arsenic-induced bladder cancer in an animal model  

SciTech Connect

Dimethylarsinic acid (DMA{sup V}) is carcinogenic to the rat urinary bladder, but not in mice. The carcinogenic mode of action involves cytotoxicity followed by regenerative cell proliferation. Dietary DMA{sup V} does not produce urinary solids or significant alterations in urinary composition. The cytotoxicity is due to formation of a reactive metabolite, likely dimethylarsinous acid (DMA{sup III}), concentrated and excreted in the urine. Urinary concentrations of DMA{sup III} are dose-dependent, and the urinary concentrations are at cytotoxic levels based on in vitro studies. The no observed effect level (NOEL) in these rat dietary studies for detectable levels of DMA{sup III}, cytotoxicity, and proliferation is 2 ppm, with marginal changes at 10 ppm. The tumorigenic dose is 100 ppm. Recent investigations have demonstrated that arsenicals administered to the rat result in binding to a specific cysteine in the hemoglobin alpha chain as DMA{sup III}, regardless of the arsenical being administered. Monomethylarsonic acid (MMA{sup V}) is not carcinogenic in rats or mice. In short term experiments ({<=} 10 weeks), sodium arsenate in the drinking water induces significant cytotoxicity and regenerative proliferation. There is little evidence that the cytotoxicity produced following administration of arsenicals is caused by oxidative damage, as antioxidants show little inhibitory activity of the cytotoxicity of the various arsenicals either in vitro or in vivo. In summary, the mode of action for DMA{sup V}-induced bladder carcinogenesis in the rat involves generation of a reactive metabolite (DMA{sup III}) leading to cytotoxicity and regenerative proliferation, is a non-linear process, and likely involves a threshold. Extrapolation to human risk needs to take this into account along with the significant differences in toxicokinetics and toxicodynamics that occur between different species.

Cohen, Samuel M. [Department of Pathology and Microbiology and Eppley Institute for Cancer Research, University of Nebraska Medical Center, Omaha, NE 68198-3135 (United States)], E-mail: scohen@unmc.edu; Ohnishi, Takamasa [Department of Pathology and Microbiology and Eppley Institute for Cancer Research, University of Nebraska Medical Center, Omaha, NE 68198-3135 (United States)], E-mail: tohnishi@unmc.edu; Arnold, Lora L. [Department of Pathology and Microbiology and Eppley Institute for Cancer Research, University of Nebraska Medical Center, Omaha, NE 68198-3135 (United States)], E-mail: llarnold@unmc.edu; Le, X. Chris [Department of Laboratory Medicine and Pathology, University of Alberta, Edmonton, Alberta, T6G 2G3 (Canada)], E-mail: xc.le@ualberta.ca

2007-08-01

317

[Activity of alanine aminopeptidase in blood and in urine of smoking and non-smoking smelters].  

PubMed

The human body is constantly exposed to xenobiotics. This will include exogenous substances from environmental pollution such as heavy metals and lifestyle such as smoking, which may lead to impaired functioning of many organs. The liver and kidney are the critical organs in the case of a long-term occupational or environmental exposure to heavy metals and tobacco smoke. In diagnostics of liver and kidney damage useful are the methods which determine the activity of enzymes such as alanine aminopeptidase (AAP). AAP is a marker for early detection of acute kidney damage, and presence of AAP derive mainly from proximal tubular brush-border. Activity of AAP in urine allows to assess the damage resulting from the nephrotoxic exposure to heavy metals. In the serum AAP is mainly from hepatic. Activity of AAP may be useful to identify liver cancer. The investigation was shown, that AAP activity in the blood is used to detect hepatic cholestasis and congestive jaundice. The aim of present study was to assess the influence of occupational exposure of copper-foundry workers to heavy metals (arsenic, cadmium, lead) on activity of alanine aminopeptidase in blood and urine. The investigations were performed in blood and urine of 166 subjects: 101 male copper smelters and 65 non-exposed male subjects. The study protocol was approved by Local Bioethics Committee of Wroclaw Medical University (KB No: 469/2008). The data on smoking which had been obtained from a direct personal interview were verified by determination of serum cotinine concentrations. Biological material collected from the control group and smelters was divided into subgroups of nonsmokers and smokers. The concentrations of lead and cadmium were determined in whole blood, whilst the level of arsenic and cadmium were determined in urine using FAAS method (Flame Atomic Absorption Spectrometry) in the acetylate flame on the SOLAAR M6. The activity of AA was determined in blood and in urine. The results showed a 9-fold increase in the concentration of lead and 10-fold elevation of arsenic level in all groups of smelters in comparison to the control group. The highest cadmium, lead and arsenic concentrations were observed in blood and urine of smoking smelters. We have observed a significant increase in the concentrations of lead and cadmium in blood of smoking persons from control group in comparison to the non-smoking persons from this group, which suggest, that tobacco smoking increase the heavy metals concentrations in the organisms. Occupational exposure to heavy metals resulted in an increase of AAP activity in blood and urine of all groups of smelters in comparison to corresponding control groups. The highest value of AAP was observed in serum and urine of smoking smelters. Tobacco smoke also increases the AAP activity the blood and urine of smoking smelters and control group compared to the non-smoking smelters and nonsmoking control group, appropriate. The study was shown that occupational exposure to heavy metals and tobacco. PMID:21360924

Bizo?, Anna; Stasiak, Karolina; Milnerowicz, Halina

2010-01-01

318

Arsenic for the fool: an exponential connection.  

PubMed

Anthropogenic arsenic is insidiously building up together with natural arsenic to a level unprecedented in the history of mankind. Arsenopyrite (FeAsS) is the principal ore of arsenic and gold in hard rock mines; it is formed by a coupled substitution of sulphur by arsenic in the structure of pyrite (FeS(2)) - nicknamed "fool's gold". Other important sources of anthropogenic arsenic are fossil fuels such as coal and oil. Here I report on the first indication that the environmental concentration of total arsenic in topsoils - in the 7-18ppm range - is exponentially related to the prevalence and mortality of Alzheimer's disease and other dementias in European countries. This evidence defies the imputed absence of verified cases of human morbidity or mortality resulting from exposure to low-level arsenic in topsoils. PMID:20123147

Dani, Sergio U

2010-03-15

319

Variability of urine albumin excretion in normal and diabetic children  

Microsoft Academic Search

The variability of urine albumin excretion (UAE) was studied in normal and diabetic children and, in addition, the best method of expressing the data was investigated. In 39 timed overnight urine samples from diabetic children, the urine albumin creatinine clearance ratio (CA\\/CC) was compared with the urine albumin creatinine concentration ratio (UA\\/UC), the urine albumin excretion rate (UAER) and the

Diana M. Gibb; Vanita Shah; Michael Preece; T. Martin Barratt

1989-01-01

320

COMPARISON OF THE URINARY METABOLITES OF RATS, MICE, AND HUMANS AFTER ORAL ARSENIC EXPOSURE FOCUSING ON THIOARSENICALS  

EPA Science Inventory

Urinary metabolites of arsenic are useful as biomarkers of exposure because ingested arsenic is excreted primarily in urine1. Complete urinary arsenic speciation can provide insight into possible metabolic pathways as well as potential exposure sources. The pattern of excreted me...

321

Determination of arsenic compounds in earthworms  

SciTech Connect

Earthworms and soil collected from six sites in Styria, Austria, were investigated for total arsenic concentrations by ICP-MS and for arsenic compounds by HPLC-ICP-MS. Total arsenic concentrations ranged from 3.2 to 17.9 mg/kg dry weight in the worms and from 5.0 to 79.7 mg/kg dry weight in the soil samples. There was no strict correlation between the total arsenic concentrations in the worms and soil. Arsenic compounds were extracted from soil and a freeze-dried earthworm sample with a methanol/water mixture (9:1, v/v). The extracts were evaporated to dryness, redissolved in water, and chromatographed on an anion- and a cation-exchange column. Arsenic compounds were identified by comparison of the retention times with known standards. Only traces of arsenic acid could be extracted from the soil with the methanol/water (9:1, v/v) mixture. The major arsenic compounds detected in the extracts of the earthworms were arsenous acid and arsenic acid. Arsenobetaine was present as a minor constituent, and traces of dimethylarsinic acid were also detected. Two dimethylarsinoyltribosides were also identified in the extracts by co-chromatography with standard compounds. This is the first report of the presence of dimethylarsinoylribosides in a terrestrial organism. Two other minor arsenic species were present in the extract, but their retention times did not match with the retention times of the available standards.

Geiszinger, A.; Goessler, W.; Kuehnelt, D.; Kosmus, W. [Karl-Franzens-Univ., Graz (Austria). Inst. for Analytical Chemistry] [Karl-Franzens-Univ., Graz (Austria). Inst. for Analytical Chemistry; Francesconi, K. [Odense Univ. (Denmark). Inst. of Biology] [Odense Univ. (Denmark). Inst. of Biology

1998-08-01

322

Effects of recharge and discharge on delta2H and delta18O composition and chloride concentration of high arsenic/fluoride groundwater from the Datong Basin, northern China.  

PubMed

To better understand the effects of recharge and discharge on the hydrogeochemistry of high levels of arsenic (As) and fluoride (F) in groundwater, environmental isotopic composition (delta2H and delta18O) and chloride (Cl) concentrations were analyzed in 29 groundwater samples collected from the Datong Basin. High arsenic groundwater samples (As > 50 micog/L) were found to be enriched in lighter isotopic composition that ranged from -92 to -78 per thousand for deuterium (delta2H) and from -12.5 to -9.9 per thousand for oxygen-18 (delta18O). High F-containing groundwater (F > 1 mg/L) was relatively enriched in heavier isotopic composition and varied from -90 to -57 per thousand and from -12.2 to -6.7 per thousand for delta2H and delta18O, respectively. High chloride concentrations and delta18O values were primarily measured in groundwater samples from the northern and southwestern portions of the study area, indicating the effect of evaporation on groundwater. The observation of relatively homogenized and low delta18O values and chloride concentrations in groundwater samples from central part of the Datong Basin might be a result of fast recharge by irrigation returns, which suggests that irrigation using arsenic-contaminated groundwater affected the occurrence of high arsenic-containing groundwater in the basin. PMID:23472327

Xie, Xianjun; Wang, Yanxin; Su, Chunli; Duan, Mengyu

2013-02-01

323

The microbial arsenic cycle in Mono Lake, California  

Microsoft Academic Search

Significant concentrations of dissolved inorganic arsenic can be found in the waters of a number of lakes located in the western USA and in other water bodies around the world. These lakes are often situated in arid, volcanic terrain. The highest concentrations of arsenic occur in hypersaline, closed basin soda lakes and their remnant brines. Although arsenic is a well-known

Ronald S. Oremland; John F. Stolz; James T. Hollibaugh

2004-01-01

324

Development of a method for the determination of bisphenol A at trace concentrations in human blood and urine and elucidation of factors influencing method accuracy and sensitivity.  

PubMed

Bisphenol A (BPA) is an industrial chemical used to make polymers including some used in food contact applications. Virtually complete presystemic clearance of orally administered BPA occurs in humans by metabolism to BPA-glucuronide (BPA-G), but some biomonitoring studies report low concentrations of free (parent) BPA in human blood and urine. Trace contamination of BPA from exogenous sources or hydrolysis of BPA-G to free BPA, either during or after biomonitoring specimen collection, may have contributed to the reported concentrations of free BPA. An analytical method for the determination of free BPA in human blood and urine was developed and validated in two independent laboratories, using the latest generation of high-performance liquid chromatography-tandem mass spectrometry instrumentation to ensure the desired high sensitivity and selectivity. The method was designed to account for and/or eliminate background contamination from all sources and demonstrated that contamination could occur from devices used for specimen collection or storage, as well as other sources. The method employed an internal standard (BPA-d(8)) and demonstrated accuracy and reproducibility in both matrices fortified with BPA or a surrogate analyte ((13)C-BPA) at a low quantitation limit (0.1-0.2 ng/mL). For validation, five replicate samples were analyzed to evaluate reproducibility. Importantly, it was demonstrated that the conditions of the method did not result in the hydrolysis of BPA-G to free BPA, another possible source of error in BPA analysis. Application of the principles defined by this method will be critical to assure valid analytical results in any future biomonitoring studies. PMID:20663281

Markham, Dan Alan; Waechter, John M; Wimber, Martina; Rao, Narayana; Connolly, Paul; Chuang, Jane Chen; Hentges, Steven; Shiotsuka, Ronald N; Dimond, Stephen; Chappelle, Anne H

2010-01-01

325

Mass Flux Measurements of Arsenic in Groundwater (Battelle Conference)  

EPA Science Inventory

Concentration trends of arsenic are typically used to evaluate the performance of remediation efforts designed to mitigate arsenic contamination in groundwater. A complementary approach would be to track changes in mass flux of the contaminant through the subsurface, for exampl...

326

Liver is a Target of Arsenic Carcinogenesis  

PubMed Central

Inorganic arsenic is clearly a human carcinogen causing tumors of the skin, lung, urinary bladder, and possibly liver (IARC, 2004). At the time of construction of this monograph, the evidence for arsenic as a hepatocarcinogen in humans was considered controversial and in rodents considered insufficient. However, recent data has accumulated indicating hepatocarcinogenicity of arsenic. This forum reevaluates epidemiology studies, rodent studies together with in vitro models, and focuses on the liver as a target organ of arsenic toxicity and carcinogenesis. Hepatocellular carcinoma and hepatic angiosarcoma, have been frequently associated with environmental or medicinal exposure to arsenicals. Preneoplastic lesions, including hepatomegaly, hepatoportal sclerosis, fibrosis, and cirrhosis often occur after chronic arsenic exposure. Recent work in mice clearly shows that exposure to inorganic arsenic during gestation induces tumors, including hepatocellular adenoma and carcinoma, in offspring when they reach adulthood. In rats, the methylated arsenicals, dimethylarsinic acid promotes diethylnitrosamine-initiated liver tumors, whereas trimethylarsine oxide induces liver adenomas. Chronic exposure of rat liver epithelial cells to low concentrations of inorganic arsenic induces malignant transformation, producing aggressive, undifferentiated epithelial tumors when inoculated into the Nude mice. There are a variety of potential mechanisms for arsenical-induced hepatocarcinogenesis, such as oxidative DNA damage, impaired DNA damage repair, acquired apoptotic tolerance, hyperproliferation, altered DNA methylation, and aberrant estrogen signaling. Some of these mechanisms may be liver specific/selective. Overall, accumulating evidence clearly indicates that the liver could be an important target of arsenic carcinogenesis.

Liu, Jie; Waalkes, Michael P.

2008-01-01

327

ARSENIC REMOVAL FROM AN EX?TIN MINING WATER POOL USING A MICROFILTRATION?COAGULATION PROCESS  

Microsoft Academic Search

The removal of arsenic from water by a microfiltration?coagulation process was investigated. In general, arsenic removal was enhanced in the presence of a coagulant. Arsenic was removed (83% and 72%) from water containing 243–255?g\\/l arsenic, resulting in arsenic concentrations of 40?g\\/L and 68?g\\/L, using microfiltration?coagulation and microfiltration, respectively. Furthermore, arsenic removal increased with decreasing specific flux, in which an almost

KATAYON SAED; MEGAT JOHARI MEGAT MOHD NOOR; AHMAD JUSOH; THAMER AHMED MOHAMED; SULEYMAN A. MUYIBI

2004-01-01

328

Arsenic Speciation in Wastes Resulting From Pressure Oxidation, Roasting and Smelting  

Microsoft Academic Search

Arsenic commonly occurs in elevated concentrations in some gold and base-metal deposits. Mining and metallurgical processing of gold and base-metal ores results in solid wastes, effluents, and air emissions containing high concentrations of arsenic. Such wastes form an important source of anthropogenic arsenic in the environment. The nature and occurrence of arsenic in solid wastes are complex and highly variable.

Paktunc

2010-01-01

329

Quality of groundwater in eastern Croatia. The problem of arsenic pollution  

Microsoft Academic Search

Groundwater in the area of eastern Croatia contains high concentrations of iron, manganese, ammonia, organic substances and arsenic. The appearance of inorganic arsenic in groundwater is mainly caused by arsenic from natural geological sources. Since the groundwater is the main source of drinking water for the population in this area, almost 200,000 people are daily drinking water with arsenic concentration

Mirna Habuda-Stani?; Mirko Kuleš; Brankica Kalajdži?; Željka Romi?

2007-01-01

330

Factors affecting the flux of arsenic through the mussel Mytilus galloprovincialis  

Microsoft Academic Search

Radiotracer experiments were designed to study the effects of certain environmental and biological factors on arsenic accumulation and elimination processes in the Mediterranean mussel Mytilus galloprovincialis. Arsenic (as arsenate) uptake increased with increasing arsenic concentration in the water; however, the response was not proportional, indicating that accumulation was partially suppressed at higher external arsenic concentrations. In general, approximately 80% of

M. Y. Ünlü; S. W. Fowler

1979-01-01

331

Arsenic geochemistry of groundwater in Southeast Asia.  

PubMed

The occurrence of high concentrations of arsenic in the groundwater of the Southeast Asia region has received much attention in the past decade. This study presents an overview of the arsenic contamination problems in Vietnam, Cambodia, Lao People's Democratic Republic and Thailand. Most groundwater used as a source of drinking water in rural areas has been found to be contaminated with arsenic exceeding the WHO drinking water guideline of 10 ?g·L(-1). With the exception of Thailand, groundwater was found to be contaminated with naturally occurring arsenic in the region. Interestingly, high arsenic concentrations (> 10 ?g·L(-1)) were generally found in the floodplain areas located along the Mekong River. The source of elevated arsenic concentrations in groundwater is thought to be the release of arsenic from river sediments under highly reducing conditions. In Thailand, arsenic has never been found naturally in groundwater, but originates from tin mining activities. More than 10 million residents in Southeast Asia are estimated to be at risk from consuming arsenic-contaminated groundwater. In Southeast Asia, groundwater has been found to be a significant source of daily inorganic arsenic intake in humans. A positive correlation between groundwater arsenic concentration and arsenic concentration in human hair has been observed in Cambodia and Vietnam. A substantial knowledge gap exists between the epidemiology of arsenicosis and its impact on human health. More collaborative studies particularly on the scope of public health and its epidemiology are needed to conduct to fulfill the knowledge gaps of As as well as to enhance the operational responses to As issue in Southeast Asian countries. PMID:22198754

Kim, Kyoung-Woong; Chanpiwat, Penradee; Hanh, Hoang Thi; Phan, Kongkea; Sthiannopkao, Suthipong

2011-12-01

332

Canadian House Dust Study: population-based concentrations, loads and loading rates of arsenic, cadmium, chromium, copper, nickel, lead, and zinc inside urban homes.  

PubMed

The Canadian House Dust Study was designed to obtain nationally representative urban house dust metal concentrations (?g g(-1)) and metal loadings (?g m(-2)) for arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), nickel (Ni), lead (Pb), and zinc (Zn). Consistent sampling of active dust of known age and provenance (area sampled) also permitted the calculation of indoor loading rates (mg m(-2) day(-1) for dust and ?g m(-2) day(-1) for metals) for the winter season (from 2007 to 2010) when houses are most tightly sealed. Geomean/median indoor dust loading rates in homes located more than 2 km away from industry of any kind (9.6/9.1 mg m(-2) day(-1); n=580) were significantly lower (p<.001) than geomean (median) dust loading rates in homes located within 2 km of industry (13.5/13.4 mg m(-2) day(-1); n=421). Proximity to industry was characterized by higher indoor metal loading rates (p<.003), but no difference in dust metal concentrations (.29?p?.97). Comparisons of non-smokers' and smokers' homes in non-industrial zones showed higher metal loading rates (.005?p?.038) in smokers' homes, but no difference in dust metal concentrations (.15?p?.97). Relationships between house age and dust metal concentrations were significant for Pb, Cd and Zn (p<.001) but not for the other four metals (.14?p?.87). All seven metals, however, displayed a significant increase in metal loading rates with house age (p<.001) due to the influence of higher dust loading rates in older homes (p<.001). Relationships between three measures of metals in house dust - concentration, load, and loading rate - in the context of house age, smoking behavior and urban setting consistently show that concentration data is a useful indicator of the presence of metal sources in the home, whereas dust mass is the overriding influence on metal loadings and loading rates. PMID:23220142

Rasmussen, Pat E; Levesque, Christine; Chénier, Marc; Gardner, H David; Jones-Otazo, Heather; Petrovic, Sanya

2013-01-15

333

Assessment of the state of the gibel carp Carassius auratus gibelio in the Amur River Basin: heavy-metal and arsenic concentrations and histopathology of internal organs.  

PubMed

This study describes the concentrations of heavy metals and arsenic (As) and the basic histopathological changes in the internal organs of gibel carp Carassius auratus gibelio from five sites of the Amur River basin. Gibel carp from Sindinskaya Passage had the highest liver concentrations of zinc (Zn) (31.95 ± 13.443), copper (Cu) (12.52 ± 5.746), manganese (9.22 ± 8.121), and cadmium (0.37 ± 0.660 mg/kg wet weight [ww]) compared with fish captured from the Bol'shoi Ussuriiskii Island area and Kadi Lake; however, concentrations of nickel (0.22 ± 0.156 mg/kg ww) were not significantly different, and concentrations of lead (0.19 ± 0.121 mg/kg ww) were higher than those in fish from Kadi Lake. Mean concentrations of metals and As in muscles were lower than Russia's recommended limits for food products; however, concentrations of Cu, Zn, and Hg in individual fish were greater than the limit. Kidney disease was detected in 100% of sampled carp. Kidney disease was characterized by the formation of numerous granulomas in kidney tissues between the renal tubules. The degree of granulomatosis varied among sites. Granulomatous kidney disease in gibel carp is widespread in many reservoirs of the lower Amur River basin. The following histopathological changes were detected in liver: vacuolization of hepatocytes, hypertrophy of multiple hepatocytes, binuclearity, presence of numerous irregularly shaped nuclei in hepatocytes, karyopyknosis, diffuse necrosis of hepatocytes (in some cases focal), and edema. Necrotic changes in hepatocytes, which are important indices of the toxic effect of pollutants, were found in the majority of investigated carp from the lower Amur River basin. Some fish had simultaneous pathological alterations in multiple organs. PMID:22012303

Syasina, Iraida G; Khlopova, Anna V; Chukhlebova, Lyubov M

2012-04-01

334

Aflatoxin B1 albumin adducts in plasma and aflatoxin M1 in urine are associated with plasma concentrations of vitamins A and E  

PubMed Central

Background Although aflatoxin exposure has been shown to be associated with micronutrient deficiency in animals, there are few investigations on the effects of aflatoxin exposure on micronutrient metabolism in humans. Objective To examine the relationship between aflatoxin B1 (AFB1) albumin adducts (AF-ALB) in plasma and the aflatoxin M1 (AFM1) metabolite in urine and plasma concentrations of retinol (vitamin A) and ?-tocopherol (vitamin E) in Ghanaians. Methods A cross-sectional study of 147 adult participants was conducted. Blood and urine samples were tested for aflatoxin and vitamins A and E levels. Results Multivariable analysis showed that participants with high AF-ALB (? 0.80 pmol/mg albumin) had increased odds of having vitamin A deficiency compared to those with lower AF-ALB [Odds Ratio (OR) = 2.61; CI = 1.03 – 6.58; p=0.04]. Participants with high AF-ALB also showed increased odds of having vitamin E deficiency but this was not statistically significant (OR = 2.4; CI = 0.96–6.05; p = 0.06). Conversely, those with higher AFM1 values had a statistically nonsignificant reduced odds of having vitamin A deficiency (OR = 0.31; CI = 1.15–0.09; p=0.05) and statistically significant reduced odds of having vitamin E deficiency (OR = 0.31; CI = 0.10 – 0.97; p = 0.04). Participants with high AF-ALB or high AFM1 (? 437.95 pg/dL creatinine) were almost 6 times more likely to be hepatitis B virus surface antigen (HBsAg)- positive (OR = 5.88; CI = 1.71–20.14; p = 0.005) and (OR = 5.84; CI = 1.15–29.54; p = 0.03) respectively. Conclusions These data indicate that aflatoxin may modify plasma micronutrient status. Thus, preventing aflatoxin exposure may greatly reduce vitamins A and E deficiencies.

Obuseh, Francis A.; Jolly, Pauline E.; Jiang, Yi; Shuaib, Faisal M. B.; Waterbor, John; Ellis, William O.; Piyathilake, Chandrika J.; Desmond, Renee A.; Afriyie-Gyawu, Evans; Phillips, Timothy D.

2011-01-01

335

The influence of arsenic speciation (AsIII & AsV) and concentration on the growth, uptake and translocation of arsenic in vegetable crops (silverbeet and amaranth): greenhouse study.  

PubMed

We examined arsenic (As) uptake by vegetable crops (amaranth, Amaranthus gangeticus, and silverbeet, Beta vulgaris) as affected by As speciation (As(III) and As(V)) and their concentrations in nutrient solution. Amaranth and silverbeet were grown in a nutrient solution containing four levels of arsenate (As(V)): 0, 1, 5, and 25 mg As/l and three levels of arsenite (As(III)): 0, 5, 10 mg As/l. Both As(V) and As(III) are phytotoxic to these crops with the latter being five times more toxic. Amaranth treated with As(III) exhibited As toxicity symptoms within 48 h of exposure and was close to death within 1 week. However, As(V) treatment did not show clear toxicity symptoms other than wilting and yield reduction at the highest dose rate of 25 mg As(V)/l. The main mechanism used by vegetable crops to tolerate As(V) is probably avoidance-limiting As transport to shoots and increasing As accumulation in the root system. When As(V) was added to the nutrient solution, the uptake of As in shoots increased and, at the highest dose (25 mg As(V)/l), 60 microg As/g DW (3.6 mg/kg FW) accumulated in the edible portion, which exceeds the WHO recommended limit for food stuffs (2 mg/kg FW) as the water contents of the crops were 94%. It is therefore important to determine the nature of the As species and their bio-accessibility. Iron treatment with 0.5 mg NaFe(III)EDTA/l dose decreased silverbeet As uptake by 45% given its affinity to bind As at the root surface or root rhizosphere and so restrict As translocation to the shoots. PMID:19225721

Rahman, Farzana; Naidu, Ravi

2009-04-01

336

Inverse association between toenail arsenic and body mass index in a population of welders.  

PubMed

Recent data show that arsenic may play a role in obesity-related diseases. However, urinary arsenic studies report an inverse association between arsenic level and body mass index (BMI). We explored whether toenail arsenic, a long-term exposure measure, was associated with BMI in 74 welders with known arsenic exposure. BMI showed significant inverse associations with toenail arsenic (p=0.01), which persisted in models adjusted for demographics, diet and work history. It is unclear whether low arsenic biomarker concentrations in high BMI subjects truly reflect lower exposures, or instead reflect internal or metabolic changes that alter arsenic metabolism and tissue deposition. PMID:24721130

Grashow, Rachel; Zhang, Jinming; Fang, Shona C; Weisskopf, Marc G; Christiani, David C; Kile, Molly L; Cavallari, Jennifer M

2014-05-01

337

Urinary trivalent methylated arsenic species in a population chronically exposed to inorganic arsenic.  

PubMed

Chronic exposure to inorganic arsenic (iAs) has been associated with increased risk of various forms of cancer and of noncancerous diseases. Metabolic conversions of iAs that yield highly toxic and genotoxic methylarsonite (MAsIII) and dimethylarsinite (DMAsIII) may play a significant role in determining the extent and character of toxic and cancer-promoting effects of iAs exposure. In this study we examined the relationship between urinary profiles of MAsIII and DMAsIII and skin lesion markers of iAs toxicity in individuals exposed to iAs in drinking water. The study subjects were recruited among the residents of an endemic region of central Mexico. Drinking-water reservoirs in this region are heavily contaminated with iAs. Previous studies carried out in the local populations have found an increased incidence of pathologies, primarily skin lesions, that are characteristic of arseniasis. The goal of this study was to investigate the urinary profiles for the trivalent and pentavalent As metabolites in both high- and low-iAs-exposed subjects. Notably, methylated trivalent arsenicals were detected in 98% of analyzed urine samples. On average, the major metabolite, DMAsIII, represented 49% of total urinary As, followed by DMAsV (23.7%), iAsV (8.6%), iAsIII (8.5%), MAsIII (7.4%), and MAsV (2.8%). More important, the average MAsIII concentration was significantly higher in the urine of exposed individuals with skin lesions compared with those who drank iAs-contaminated water but had no skin lesions. These data suggest that urinary levels of MAsIII, the most toxic species among identified metabolites of iAs, may serve as an indicator to identify individuals with increased susceptibility to toxic and cancer-promoting effects of arseniasis. PMID:15743710

Valenzuela, Olga L; Borja-Aburto, Victor H; Garcia-Vargas, Gonzalo G; Cruz-Gonzalez, Martha B; Garcia-Montalvo, Eliud A; Calderon-Aranda, Emma S; Del Razo, Luz M

2005-03-01

338

Urinary Trivalent Methylated Arsenic Species in a Population Chronically Exposed to Inorganic Arsenic  

PubMed Central

Chronic exposure to inorganic arsenic (iAs) has been associated with increased risk of various forms of cancer and of noncancerous diseases. Metabolic conversions of iAs that yield highly toxic and genotoxic methylarsonite (MAsIII) and dimethylarsinite (DMAsIII) may play a significant role in determining the extent and character of toxic and cancer-promoting effects of iAs exposure. In this study we examined the relationship between urinary profiles of MAsIII and DMAsIII and skin lesion markers of iAs toxicity in individuals exposed to iAs in drinking water. The study subjects were recruited among the residents of an endemic region of central Mexico. Drinking-water reservoirs in this region are heavily contaminated with iAs. Previous studies carried out in the local populations have found an increased incidence of pathologies, primarily skin lesions, that are characteristic of arseniasis. The goal of this study was to investigate the urinary profiles for the trivalent and pentavalent As metabolites in both high- and low-iAs–exposed subjects. Notably, methylated trivalent arsenicals were detected in 98% of analyzed urine samples. On average, the major metabolite, DMAsIII, represented 49% of total urinary As, followed by DMAsV (23.7%), iAsV (8.6%), iAsIII (8.5%), MAsIII (7.4%), and MAsV (2.8%). More important, the average MAsIII concentration was significantly higher in the urine of exposed individuals with skin lesions compared with those who drank iAs-contaminated water but had no skin lesions. These data suggest that urinary levels of MAsIII, the most toxic species among identified metabolites of iAs, may serve as an indicator to identify individuals with increased susceptibility to toxic and cancer-promoting effects of arseniasis.

Valenzuela, Olga L.; Borja-Aburto, Victor H.; Garcia-Vargas, Gonzalo G.; Cruz-Gonzalez, Martha B.; Garcia-Montalvo, Eliud A.; Calderon-Aranda, Emma S.; Del Razo, Luz M.

2005-01-01

339

Toxicity of inorganic and methylated arsenic to algal communities from lakes along an arsenic contamination gradient  

Microsoft Academic Search

The toxicity of arsenate (As(V)), arsenite (As(III)), monomethylarsonic (MMAA) and dimethylarsinic acid (DMAA) to natural algal assemblages from lakes within the Aberjona watershed having different arsenic concentrations was determined by a short-term photosynthesis assay. Total arsenic concentrations in the studied lakes ranged from 1.5×10?8 to 1.9×10?7 M. The toxicity of the arsenic species generally decreased in the order of As(V)>As(III)>DMAA

Katja Knauer; Renata Behra; Harry Hemond

1999-01-01

340

Ultratrace determination of arsenic in water samples by electrothermal atomic absorption spectrometry after pre-concentration with Mg-Al-Fe ternary layered double hydroxide nano-sorbent.  

PubMed

A selective solid phase extraction method, based on nano-structured Mg-Al-Fe(NO3(-)) ternary layered double hydroxide as a sorbent, is developed for the pre-concentration of ultra-trace levels of arsenic (As) prior to determination by electrothermal atomic absorption spectrometry. It is found that both As(III) and As(V) could be quantitatively retained on the sorbent within a wide pH range of 4-12. Accordingly, the presented method is applied to determination of total inorganic As in aqueous solutions. Maximum analytical signal of As is achieved when the pyrolysis and atomization temperatures are close to 900 °C and 2300 °C, respectively. Several variables affecting the extraction efficiency including pH, sample flow rate, amount of nano-sorbent, elution conditions and sample volume are optimized. Under the optimized conditions, the limit of detection (3Sb/m) and the relative standard deviation are 4.6 pg mL(-1) and 3.9%, respectively. The calibration graph is linear in the range of 15.0-650 pg mL(-1) with a correlation coefficient of 0.9979, sorption capacity and pre-concentration factor are 8.68 mg g(-1) and 300, respectively. The developed method is validated by the analysis of a standard reference material (SRM 1643e) and is successfully applied to the determination of ultra-trace amounts of As in different water samples. PMID:24148451

Abdolmohammad-Zadeh, Hossein; Jouyban, Abolghasem; Amini, Roghayeh

2013-11-15

341

Trace element concentrations (mercury, cadmium, copper, zinc, lead, aluminium, nickel, arsenic, and selenium) in some aquatic birds of the southwest Atlantic coast of France.  

PubMed

Trace elements (mercury [Hg], cadmium [Cd], copper [Cu], zinc [Zn], lead [Pb], aluminium [Al], nickel [Ni], arsenic [As], and selenium [Se]) were investigated using inductively coupled plasma-mass spectrometry in liver, kidney, muscle, and feather of aquatic birds wintering or inhabiting the wetlands situated on the Southwest Atlantic coast of France. A majority of greylag geese, red knots, and grey plovers were collected from among hunter-shot animals. The relation between residue concentrations, age (juvenile vs. adult), and sex was investigated. Trace elements were lower than threshold levels of toxicity, except for Pb. Greylag geese sampled could be considered Pb-poisoned. These consequential levels of contamination could be the result of the ingestion of Pb-shot from ammunition used in hunting areas they crossed during migration. Cd accumulation increased with age, whereas Pb levels in feathers were lower in adult birds in connection with moulting. As was influenced by sex. Female birds displayed higher concentrations in liver and feathers than did male birds. PMID:19763676

Lucia, Magali; André, Jean-Marc; Gontier, Karine; Diot, Nicolas; Veiga, Jesus; Davail, Stéphane

2010-04-01

342

Chloride - urine test  

MedlinePLUS

The urine chloride test measures the amount of chloride in urine. ... After you provide a urine sample, it is tested in the lab. If needed, the health care provider may ask you to collect your urine ...

343

Arsenic removal from drinking water during coagulation  

SciTech Connect

The efficiency of arsenic removal from source waters and artificial freshwaters during coagulation with ferric chloride and alum was examined in bench-scale studies. Arsenic(V) removal by either ferric chloride or alum was relatively insensitive to variations in source water composition below pH 8. At pH 8 and 9, the efficiency of arsenic(V) removal by ferric chloride was decreased in the presence of natural organic matter. The pH range for arsenic(V) removal with alum was more restricted than with ferric chloride. For source waters spiked with 20 {micro}g/L arsenic(V), final dissolved arsenic(V) concentrations in the product water of less than 2 {micro}g/L were achieved with both coagulants at neutral pH. Removal of arsenic(III) from source waters by ferric chloride was both less efficient and more strongly influenced by source water composition than removal of arsenic(V). The presence of sulfate (at pH 4 and 5) and natural organic matter (at pH 4 through 9) adversely affected the efficiency of arsenic(III) removal by ferric chloride. Arsenic(III) could not be removed from source waters by coagulation with alum.

Hering, J.G. [California Inst. of Tech., Pasadena, CA (United States); Chen, P.Y. [Industrial Technology Research Inst., Chutung Hsinchu (Taiwan, Province of China); Wilkie, J.A.; Elimelech, M. [Univ. of California, Los Angeles, CA (United States). Dept. of Civil and Environmental Engineering

1997-08-01

344

Arsenic methylation capacity, body retention, and null genotypes of glutathione S-transferase M1 and T1 among current arsenic-exposed residents in Taiwan  

Microsoft Academic Search

In order to elucidate the relationships among arsenic methylation capacity, body retention, and genetic polymorphisms of glutathione S-transferase (GST) M1 and T1, a total of 115 study subjects were recruited from Lanyang Basin located on the northeast coast of Taiwan. Specimens of drinking water, blood, urine, hair and toenail were collected from each study subject. Urinary inorganic and methylated arsenic

Hung-Yi Chiou; Yu-Mei Hsueh; Ling-Ling Hsieh; Ling-I Hsu; Yi-Hsiang Hsu; Fang-I Hsieh; Min-Li Wei; Hsiang-Chih Chen; Hui-Ting Yang; Lan-Chin Leu; Tzu-Hsien Chu; Chuan Chen-Wu; Mo-Hsiung Yang; Chien-Jen Chen

1997-01-01

345

Arsenic removal by ferric chloride  

SciTech Connect

Bench-scale studies were conducted in model freshwater systems to investigate how various parameters affected arsenic removal during coagulation with ferric chloride and arsenic adsorption onto preformed hydrous ferric oxide. Parameters included arsenic oxidation state and initial concentration, coagulant dosage or adsorbent concentration, pH, and the presence of co-occurring inorganic solutes. Comparison of coagulation and adsorption experiments and of experimental results with predictions based on surface complexation modeling demonstrated that adsorption is an important (though not the sole) mechanism governing arsenic removal during coagulation. Under comparable conditions, better removal was observed with arsenic(V) [As(V)] than with arsenic(III) [As(III)] in both coagulation and adsorption experiments. Below neutral pH values, As(III) removal-adsorption was significantly decreased in the presence of sulfate, whereas only a slight decrease in As(V) removal-adsorption was observed. At high pH, removal-adsorption of As(V) was increased in the presence of calcium. Removal of As(V) during coagulation with ferric chloride is both more efficient and less sensitive than that of As(III) to variations in source water composition.

Hering, J.G.; Chen, P.Y.; Wilkie, J.A.; Elimelech, M. [Univ. of California, Los Angeles, CA (United States). Dept. of Civil and Environmental Engineering; Liang, S. [Metropolitan Water District of Southern California, La Verne, CA (United States)

1996-04-01

346

TRACE ANALYSIS OF ARSENIC BY COLORIMETRY, ATOMIC ABSORPTION, AND POLAROGRAPHY  

EPA Science Inventory

A differential pulse polarographic method was developed for determining total arsenic concentrations in water samples from ash ponds at steam-electric generating plants. After digestion of the sample and isolation of arsenic by solvent extraction, the peak current for arsenic is ...

347

XAS Studies of Arsenic in the Environment  

SciTech Connect

Arsenic is present in low concentrations in much of the Earth's crust and changes in its speciation are vital to understanding its transport and toxicity in the environment. We have used X-ray absorption spectroscopy to investigate the coordination sites of arsenic in a wide variety of samples, including soil and earthworm tissues from arsenic-contaminated land, and human hair and nail samples from people exposed to arsenic in Cambodia. Our results confirm the effectiveness of using X-ray absorption near edge structure (XANES) and X-ray absorption fine structure (EXAFS) spectroscopy to determine speciation changes in environmental samples.

Charnock, J. M. [CCLRC Daresbury Laboratory, Warrington, Cheshire, WA4 4AD (United Kingdom); School of Earth, Atmospheric and Environmental Sciences, University of Manchester, Oxford Road, Manchester, M13 9PL (United Kingdom); Polya, D. A.; Gault, A. G. [School of Earth, Atmospheric and Environmental Sciences, The University of Manchester, Oxford Road, Manchester, M13 9PL (United Kingdom); Morgan, A. J. [School of Biosciences, Cardiff University, Cardiff, CF10 3TL (United Kingdom)

2007-02-02

348

Urine concentrating mechanism: impact of vascular and tubular architecture and a proposed descending limb urea-Na+ cotransporter  

PubMed Central

We extended a region-based mathematical model of the renal medulla of the rat kidney, previously developed by us, to represent new anatomic findings on the vascular architecture in the rat inner medulla (IM). In the outer medulla (OM), tubules and vessels are organized around tightly packed vascular bundles; in the IM, the organization is centered around collecting duct clusters. In particular, the model represents the separation of descending vasa recta from the descending limbs of loops of Henle, and the model represents a papillary segment of the descending thin limb that is water impermeable and highly urea permeable. Model results suggest that, despite the compartmentalization of IM blood flow, IM interstitial fluid composition is substantially more homogeneous compared with OM. We used the model to study medullary blood flow in antidiuresis and the effects of vascular countercurrent exchange. We also hypothesize that the terminal aquaporin-1 null segment of the long descending thin limbs may express a urea-Na+ or urea-Cl? cotransporter. As urea diffuses from the urea-rich papillary interstitium into the descending thin limb luminal fluid, NaCl is secreted via the cotransporter against its concentration gradient. That NaCl is then reabsorbed near the loop bend, raising the interstitial fluid osmolality and promoting water reabsorption from the IM collecting ducts. Indeed, the model predicts that the presence of the urea-Na+ or urea- Cl? cotransporter facilitates the cycling of NaCl within the IM and yields a loop-bend fluid composition consistent with experimental data.

Dantzler, William H.; Pannabecker, Thomas L.

2012-01-01

349

Arsenic in hair and nails of individuals exposed to arsenic-rich groundwaters in Kandal province, Cambodia  

Microsoft Academic Search

The health implications of the consumption of high arsenic groundwater in Bangladesh and West Bengal are well-documented, however, little is known about the level of arsenic exposure elsewhere in Southeast Asia, where widespread exploitation of groundwater resources is less well established. We measured the arsenic concentrations of nail and hair samples collected from residents of Kandal province, Cambodia, an area

Andrew G. Gault; Helen. A. L. Rowland; John M. Charnock; Roy A. Wogelius; Inma Gomez-Morilla; Sovathana Vong; Moniphea Leng; Sopheap Samreth; Mickey L. Sampson; David A. Polya

2008-01-01

350

[Urinary N-acetyl-beta-D-glucosaminidase and its isoenzymes in smoking and non-smoking workers at copper foundry occupational co-exposed to arsenic cadmium and lead].  

PubMed

The kidneys are the critical organs in the case of a long-term occupational or environmental exposure to heavy metals and tobacco smoke. In diagnostics of renal damage useful are the methods which determine the activity of renal enzymes, quantify in urine (e.g. beta-glucuronidase, N-acetyl-beta-D-glucosaminidase). N-acetyl-beta-D-glucosaminidase (NAG) is one of the most often determined factors of tubular damage, since its activity increases in early stages of renal injury, ahead of appearance of excretory dysfunction. The aim of this research was to assess the influence of occupational exposure of copper-foundry workers to heavy metals (arsenic, cadmium, lead) on total activity of N-acetyl-beta-D-glucosaminidase and its molecular forms in urine. The investigated group was made up of 95 founders (smokers n = 51, non-smokers n = 44) and 43 people in control group (smokers n = 16, non-smokers n = 27). The concentrations of arsenic (As) and cadmium (Cd) were determined in urine, whilst the level of lead (Pb) was determined in whole blood. The activities of NAG and its isoforms were determined in urine. Smoking and non-smoking founders' urine demonstrated 14 times higher concentrations of arsenic levels in comparison with smoking and nonsmoking control group. Cadmium concentrations were 3.5 times higher in urine of smoking founders in comparison with smoking control group and about 3 times higher in case of nonsmoking founders in comparison with non-smoking control group. 7 times increase of lead concentration was observed in the whole blood within the smoking founders group in comparison with the smoking control group. In the blood of non-smoking founders was demonstrated about 10 times increase of lead concentration in comparison with the non-smoking control group. About 3-times increase of total NAG's activity was observed in urine of smoking founders and 4-times increase of non-smoking founders in comparison with smoking and non-smoking control group. The highest activity of NAG-B was observed in urine of smoking founders (11.35 +/- 7.85 U/g creatinine), then non-smoking founders (9.7 +/- 8.75 U/ g creatinine). It was confirmed, that the activity of N-acetyl-beta-D-glucosaminidase is a good factor in the assessment of occupational exposure to heavy metals like arsenic, cadmium and lead. PMID:19189537

Milnerowicz, Halina; Bizo?, Anna; Witt, Katarzyna; Antonowicz-Juchniewicz, Jolanta; Andrzejak, Ryszard

2008-01-01

351

Fluoroquinolone levels in healthy dog urine following a 20-mg/kg oral dose of enrofloxacin exceed mutant prevention concentration targets against Escherichia coli isolated from canine urinary tract infections.  

PubMed

A 3-day course of oral enrofloxacin is effective for treating uncomplicated urinary tract infection (UTI) in dogs when administered 20 mg/kg Q24H. However, emergence of fluoroquinolone-resistant mutants of uropathogens is a concern. Urine concentrations of enrofloxacin and ciprofloxacin were measured in six healthy dogs following dose of enrofloxacin 20 mg/kg. Mutant prevention concentrations of Escherichia coli isolated from canine UTI were also determined against ciprofloxacin. Urine AUC(24)/MPC ratios considering ciprofloxacin concentrations ranged 3819-7767, indicating that selection of resistant E. coli mutants in dogs with uncomplicated UTIs is unlikely in the bladder given that an AUC(24)/MPC = 39 is considered to be protective against mutant selection for ciprofloxacin. However, additional studies are required to evaluate the effects of this enrofloxacin treatment protocol on bacteria that colonize anatomic sites where fluoroquinolones achieve lower concentrations compared to the urinary bladder. PMID:23859001

Daniels, J B; Tracy, G; Irom, S J; Lakritz, J

2014-04-01

352

A Weibull-PBPK model for assessing risk of arsenic-induced skin lesions in children  

Microsoft Academic Search

Chronic arsenic exposure and skin lesions (keratosis and hyperpigmentation) are inextricably linked. This paper was to quantify the children skin lesions risks and to further recommend safe drinking water arsenic standard based on reported arsenic epidemiological data. We linked the Weibull dose–response function and a physiologically based pharmacokinetic (PBPK) model to estimate safe drinking water arsenic concentrations and to perform

Chung-Min Liao; Tzu-Ling Lin; Szu-Chieh Chen

2008-01-01

353

Identifying US populations for the study of health effects related to drinking water arsenic  

Microsoft Academic Search

The US Environmental Protection Agency recently set a new maximum contaminant level (MCL) for arsenic in drinking water of 10 ?g\\/l. In this paper, we review the completeness and accuracy of drinking water arsenic occurrence data in the United States and identify populations exposed to elevated arsenic concentrations that would be suitable for epidemiological studies of arsenic health effects. Using

Floyd J Frost; Timothy Muller; Hans V Petersen; Bruce Thomson; Kristine Tollestrup

2003-01-01

354

Arsenic-induced mitochondrial instability leading to programmed cell death in the exposed individuals  

Microsoft Academic Search

In West Bengal, India, more than 6 million people in nine districts are exposed to arsenic through drinking water. It is regarded as the greatest arsenic calamity in the world. Arsenic is a well-documented human carcinogen, which does not induce cancer in any other animal model. Interestingly, at lower concentrations, arsenic is known to induce apoptosis in various cancer cell

Nilanjana Banerjee; Mayukh Banerjee; Sudipto Ganguly; Santu Bandyopadhyay; Jayanta K. Das; Apurba Bandyopadhay; Mitali Chatterjee; Ashok K. Giri

2008-01-01

355

Arsenic, Boron, and Fluoride Concentrations in Ground Water in and Near Diabase Intrusions, Newark Basin, Southeastern Pennsylvania.  

National Technical Information Service (NTIS)

During an investigation in 2000 by the U.S. Environmental Protection Agency (USEPA) of possible contaminant releases from an industrial facility on Congo Road near Gilbertsville in Berks and Montgomery Counties, southeastern Pennsylvania, concentrations o...

L. A. Senior R. A. Sloto

2006-01-01

356

Removal of arsenic from water by electrocoagulation  

Microsoft Academic Search

In the present study electrocoagulation (EC) has been evaluated as a treatment technology for arsenite [As(III)] and arsenate [As(V)] removal from water. Laboratory scale experiments were conducted with three electrode materials namely, iron, aluminum and titanium to assess their efficiency. Arsenic removal obtained was highest with iron electrodes. EC was able to bring down aqueous phase arsenic concentration to less

P Ratna Kumar; Sanjeev Chaudhari; Kartic C Khilar; S. P Mahajan

2004-01-01

357

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

358

Arsenic Trioxide and Leukemia  

Microsoft Academic Search

Cumulative evidence indicates that traditional Chinese medicine (TCM) is an important resource for discoveries of drugs against\\u000a cancer. Arsenic, a common, naturally existing substance, is rarely found in its pure elemental state in nature. In addition\\u000a to the organic arsenicals, there are three major inorganic arsenic forms: red arsenic (As2S2), yellow arsenic (As2S3), and white arsenic (As2O3, ATO). Based on

Guo-Qiang Chen; Qiong Wang; Hua Yan; Zhu Chen

359

Biological monitoring of occupational exposure to inorganic arsenic  

PubMed Central

OBJECTIVES: This study was undertaken to assess reliable biological indicators for monitoring the occupational exposure to inorganic arsenic (iAs), taking into account the possible confounding role of arsenicals present in food and of the element present in drinking water. METHODS: 51 Glass workers exposed to As trioxide were monitored by measuring dust in the breathing zone, with personal air samplers. Urine samples at the end of work shift were analysed for biological monitoring. A control group of 39 subjects not exposed to As, and eight volunteers who drank water containing about 45 micrograms/l iAs for a week were also considered. Plasma mass spectrometry (ICP-MS) was used for the analysis of total As in air and urine samples, whereas the urinary As species (trivalent, As3; pentavalent, As5; monomethyl arsonic acid, MMA; dimethyl arsinic acid, DMA; arsenobetaine, AsB) were measured by liquid chromatography coupled with plasma mass spectrometry (HPLC-MS) RESULTS: Environmental concentrations of As in air varied widely (mean 84 micrograms/m3, SD 61, median 40) and also the sum of urinary iAs MMA and DMA, varied among the groups of exposed subjects (mean 106 micrograms/l, SD 84, median 65). AsB was the most excreted species (34% of total As) followed by DMA (28%), MMA (26%), and As3 + As5 (12%). In the volunteers who drank As in the water the excretion of MMA and DMA increased (from a median of 0.5 to 5 micrograms/day for MMA and from 4 to 13 micrograms/day for DMA). The best correlations between As in air and its urinary species were found for total iAs and As3 + As5. CONCLUSIONS: To avoid the effect of As from sources other than occupation on urinary species of the element, in particular on DMA, it is proposed that urinary As3 + As5 may an indicator for monitoring the exposure to iAs. For concentrations of 10 micrograms/m3 the current environmental limit for iAs, the limit for urinary As3 + As5 was calculated to be around 5 micrograms/l, even if the wide variation of values needs critical evaluation and application of data. The choice of this indicator might be relevant also from a toxicological point of view. Trivalent arsenic is in fact the most active species and its measure in urine could be the best indicator of some critical effects of the element, such as cancer.  

Apostoli, P.; Bartoli, D.; Alessio, L.; Buchet, J. P.

1999-01-01

360

Effects on milk urea concentration, urine output, and drinking water intake from incremental doses of potassium bicarbonate fed to mid-lactation dairy cows.  

PubMed

Large variation exists in the potassium content of dairy cow feeds and also within a feed type due to soil type and fertilization. Increased ration K concentration causes a subsequent increase in urinary volume and could be expected to also lower milk urea concentration. Six multiparous mid-lactation Swedish Red dairy cows, all fitted with rumen cannulas, were subjected to 3 different levels of K intake in a Latin square experiment with three 2-wk periods to evaluate the effects on concentrations of milk urea and rumen ammonia, urinary output, and drinking water intake. The treatments were achieved by K supplementation on top of a low-K basal ration fed at individual allowances fixed throughout the experiment. The basal ration, consumed at 20.2kg of dry matter (DM)/d, provided 165g of crude protein/kg of DM and consisted of grass silage, concentrates, and urea in the proportions 39.3:60.0:0.7 on a DM basis. Potassium bicarbonate supplementation was 0, 616, and 1,142g/d, respectively, to give total ration K concentrations that were low (LO; 12g/kg of DM), medium (MED; 23g/kg of DM), or high (HI; 32g/kg of DM). Production and composition of milk was not affected by treatment. A linear effect on milk urea concentration was detected, being 4.48, 4.18, and 3.77mM for LO, MED, and HI, respectively, and a linear tendency for rumen ammonia concentration with 6.65, 6.51, and 5.84mg of NH3-N/dL for LO, MED, and HI, respectively. Milk urea concentration peaked about 3h after the rumen ammonia peak from the morning feeding, at a level 1.3mM over the baseline. Urinary urea excretion declined linearly (105, 103, and 98g of urea-N/d for LO, MED, and HI, respectively). Linear increases occurred in urinary output (0.058±0.001kg of urine/g of K intake; no intercept; coefficient of determination=0.997) and drinking water intake (65.9±2.02 + 0.069±0.004kg of water/g of K intake; coefficient of determination=0.95). Urinary K concentration leveled off at 12.4g/L. Urinary creatinine excretion was not affected by K addition, but allantoin excretion increased linearly by 27% from LO to HI, suggesting increased rumen microbial growth. Rumen pH, acetate proportion of total volatile fatty acids, and digestibility of DM, organic matter, and neutral detergent fiber increased linearly with increasing potassium intake. We concluded that increased ration K concentration lowers milk urea concentration with a magnitude significant for the interpretation of milk urea values, but other sources of variation, such as sampling time relative to feeding, may be even more important. PMID:24835966

Eriksson, T; Rustas, B-O

2014-07-01

361

Arsenic concentrations in paddy soil and rice and health implications for major rice-growing regions of Cambodia.  

PubMed

Despite the global importance of As in rice, research has primarily focused on Bangladesh, India, China, and the United States with limited attention given to other countries. Owing to both indigenous As within the soil and the possible increases arising from the onset of irrigation with groundwater, an assessment of As in rice within Cambodia is needed, which offers a "base-case" comparison against sediments of similar origin that comprise rice paddy soils where As-contaminated water is used for irrigation (e.g., Bangladesh). Here, we evaluated the As content of rice from five provinces (Kandal, Prey Veng, Battambang, Banteay Meanchey, and Kampong Thom) in the rice-growing regions of Cambodia and coupled that data to soil-chemical factors based on extractions of paddy soil collected and processed under anoxic conditions. At total soil As concentrations ranging 0.8 to 18 ?g g(-1), total grain As concentrations averaged 0.2 ?g g(-1) and ranged from 0.1 to 0.37 with Banteay Meanchey rice having significantly higher values than Prey Veng rice. Overall, soil-extractable concentrations of As, Fe, P, and Si and total As were poor predictors of grain As concentrations. While biogeochemical factors leading to reduction of As(V)-bearing Fe(III) oxides are likely most important for predicting plant-available As, husk and straw As concentrations were the most significant predictors of grain-As levels among our measured parameters. PMID:24712677

Seyfferth, Angelia L; McCurdy, Sarah; Schaefer, Michael V; Fendorf, Scott

2014-05-01

362

Determination of eight elements in animal chow, urine and wastewater. Final report  

SciTech Connect

Analytical procedures are described for the analysis of arsenic, calcium, cadmium, copper, lead, mercury, selenium, and zinc in animal feed. Mercury is determined by digesting the feed sample with concentrated HNO/sub 3/ and H/sub 2/SO/sub 4/ plus V2O5 as an oxidation catalyst, reducing the stannous chloride, and sweeping the elemental mercury into an absorption tube for measurement by atomic absorption (AA) spectrophotometry. Arsenic and selenium are determined simultaneously by digesting the sample with concentrated HNO/sub 3/, H/sub 2/SO/sub 4/, and HClO/sub 4/; forming their respective hybrides with the addition of sodium borohybride, which are swept into an argon-hydrogen flame for analysis by AA. A low temperature ash is prepared and dissolved in 1 N HNO/sub 3/ for the analysis of calcium, copper, and zinc, by emission spectroscopy using the inductively coupled argon plasma (ICAP) source. The same solution is used for the determination of cadmium and lead by flameless AA. Animal feed spiked with three levels of each of the eight elements yielded recoveries of between 80 and 107%. Development of specific methods for the recovery of these elements for wastewater and human urine was suspended due to overriding priorities within the Analytical Methods Branch. However, a method was developed for mercury in urine and blood to address the safety surveillance requirement for NCTR workers potentially exposed to methyl mercury chloride while dosing test animals with this chemical.

Blakemore, W.M.

1981-02-01

363

Mathematical model insights into arsenic detoxification  

PubMed Central

Background Arsenic in drinking water, a major health hazard to millions of people in South and East Asia and in other parts of the world, is ingested primarily as trivalent inorganic arsenic (iAs), which then undergoes hepatic methylation to methylarsonic acid (MMAs) and a second methylation to dimethylarsinic acid (DMAs). Although MMAs and DMAs are also known to be toxic, DMAs is more easily excreted in the urine and therefore methylation has generally been considered a detoxification pathway. A collaborative modeling project between epidemiologists, biologists, and mathematicians has the purpose of explaining existing data on methylation in human studies in Bangladesh and also testing, by mathematical modeling, effects of nutritional supplements that could increase As methylation. Methods We develop a whole body mathematical model of arsenic metabolism including arsenic absorption, storage, methylation, and excretion. The parameters for arsenic methylation in the liver were taken from the biochemical literature. The transport parameters between compartments are largely unknown, so we adjust them so that the model accurately predicts the urine excretion rates of time for the iAs, MMAs, and DMAs in single dose experiments on human subjects. Results We test the model by showing that, with no changes in parameters, it predicts accurately the time courses of urinary excretion in mutiple dose experiments conducted on human subjects. Our main purpose is to use the model to study and interpret the data on the effects of folate supplementation on arsenic methylation and excretion in clinical trials in Bangladesh. Folate supplementation of folate-deficient individuals resulted in a 14% decrease in arsenicals in the blood. This is confirmed by the model and the model predicts that arsenicals in the liver will decrease by 19% and arsenicals in other body stores by 26% in these same individuals. In addition, the model predicts that arsenic methyltransferase has been upregulated by a factor of two in this population. Finally, we also show that a modification of the model gives excellent fits to the data on arsenic metabolism in human cultured hepatocytes. Conclusions The analysis of the Bangladesh data using the model suggests that folate supplementation may be more effective at reducing whole body arsenic than previously expected. There is almost no data on the upregulation of arsenic methyltransferase in populations chronically exposed to arsenic. Our model predicts upregulation by a factor of two in the Bangladesh population studied. This prediction should be verified since it could have important public health consequences both for treatment strategies and for setting appropriate limits on arsenic in drinking water. Our model has compartments for the binding of arsenicals to proteins inside of cells and we show that these comparments are necessary to obtain good fits to data. Protein-binding of arsenicals should be explored in future biochemical studies.

2011-01-01

364

A Population-based Case-Control Study of Urinary Arsenic Species and Squamous Cell Carcinoma in New Hampshire, USA  

PubMed Central

Background: Chronic high arsenic exposure is associated with squamous cell carcinoma (SCC) of the skin, and inorganic arsenic (iAs) metabolites may play an important role in this association. However, little is known about the carcinogenicity of arsenic at levels commonly observed in the United States. Objective: We estimated associations between total urinary arsenic and arsenic species and SCC in a U.S. population. Methods: We conducted a population-based case–control SCC study (470 cases, 447 controls) in a U.S. region with moderate arsenic exposure through private well water and diet. We measured urinary iAs, monomethylarsonic acid (MMA), and dimethylarsinic acid (DMA), and summed these arsenic species (?As). Because seafood contains arsenolipids and arsenosugars that metabolize into DMA through alternate pathways, participants who reported seafood consumption within 2 days before urine collection were excluded from the analyses. Results: In adjusted logistic regression analyses (323 cases, 319 controls), the SCC odds ratio (OR) was 1.37 for each ln-transformed microgram per liter increase in ln-transformed ?As concentration [ln(?As)] (95% CI: 1.04, 1.80). Urinary ln(MMA) and ln(DMA) also were positively associated with SCC (OR = 1.34; 95% CI: 1.04, 1.71 and OR = 1.34; 95% CI: 1.03, 1.74, respectively). A similar trend was observed for ln(iAs) (OR = 1.20; 95% CI: 0.97, 1.49). Percent iAs, MMA, and DMA were not associated with SCC. Conclusions: These results suggest that arsenic exposure at levels common in the United States relates to SCC and that arsenic metabolism ability does not modify the association. Citation: Gilbert-Diamond D, Li Z, Perry AE, Spencer SK, Gandolfi AJ, Karagas MR. 2013. A population-based case–control study of urinary arsenic species and squamous cell carcinoma in New Hampshire, USA. Environ Health Perspect 121:1154–1160;?http://dx.doi.org/10.1289/ehp.1206178

Li, Zhigang; Perry, Ann E.; Spencer, Steven K.; Gandolfi, A. Jay; Karagas, Margaret R.

2013-01-01

365

Urinary arsenic and porphyrin profile in C57BL/6J mice chronically exposed to monomethylarsonous acid (MMA{sup III}) for two years  

SciTech Connect

Arsenicals are proven carcinogens in humans and it imposes significant health impacts on both humans and animals. Recently monomethylarsonous acid (MMA{sup III}), the toxic metabolite of arsenic has been identified in human urine and believed to be more acutely toxic than arsenite and arsenate. Arsenic also affects the activity of a number of haem biosynthesis enzymes. As a part of 2-year arsenic carcinogenicity study, young female C57BL/6J mice were given drinking water containing 0, 100, 250 and 500 {mu}g/L arsenic as MMA{sup III}ad libitum. 24 h urine samples were collected at 0, 1, 2, 4, 8 weeks and every 8 weeks for up to 104 weeks. Urinary arsenic speciation and porphyrins were measured using HPLC-ICP-MS and HPLC with fluorescence detection respectively. DMA{sup V} was a major urinary metabolite detected. Significant dose-response relationship was observed between control and treatment groups after 1, 4, 24, 32, 48, 56, 88, 96 and 104 weeks. The level of uroporphyrin in 250 and 500 {mu}g As/L group is significantly different from the control group after 4, 8, 16, 32, 56, 72, 80, 96 and 104 weeks. Coproporphyrin I level in 500 {mu}As/L group is significantly different from control group after 8, 24, 32, 40, 56, 72, 80, 88 and 104 weeks. After 4 weeks the level of coproporphyrin III concentration significantly increased in all the treatment groups compared to the control except week 16 and 48. Our results show urinary DMA{sup V} and porphyrin profile can be used as an early warning biomarker for chronic MMA{sup III} exposure before the onset of cancer.

Krishnamohan, Manonmanii; Qi, Lixia [National Research Centre for Environmental Toxicology, University of Queensland, 39 Kessels Road, Coopersplains, Brisbane, Qld 4108 (Australia); Lam, Paul K.S. [Department of Biology and Chemistry, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon, Hong Kong (China); Moore, Michael R. [National Research Centre for Environmental Toxicology, University of Queensland, 39 Kessels Road, Coopersplains, Brisbane, Qld 4108 (Australia); Ng, Jack C. [National Research Centre for Environmental Toxicology, University of Queensland, 39 Kessels Road, Coopersplains, Brisbane, Qld 4108 (Australia)], E-mail: j.ng@uq.edu.au

2007-10-01

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Arsenic species and chemistry in groundwater of southeast Michigan  

USGS Publications Warehouse

Groundwater samples, taken from 73 wells in 10 counties of southeast Michigan in 1997 had arsenic concentrations in the range of 0.5 to 278 ??g/l, the average being 29 ??g/l. About 12% of these wells had arsenic concentrations that exceeded the current USEPA's maximum contaminant level of 50 ??g/l. Most (53-98%) of the arsenic detected was arsenite [As(III)] and other observations supported the arsenic species distribution (low redox potential and DO). In shallow groundwater (15 m), the concentration of arsenic is possibly controlled by reductive dissolution of arsenic-rich iron hydroxide/oxyhydroxide and dissolution of arsenic sulfide minerals. ?? 2002 Elsevier Science Ltd. All rights reserved.

Kim, M. -J.; Nriagu, J.; Haack, S.

2002-01-01