Wyniki wyszukiwania - Biblioteka Nauki

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Speciation of arsenic in groundwater and technologies for removal of arsenic in drinking water in the spiro tunnel bulkhead, Park City, Utah, USA

100%

Pawlak Z. , Rabiega G. , Scanlan L. , Cartwright P.

Ars Separatoria Acta

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2003

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tom No. 2

71-83

EN

Application of an anion exchange resin column was performed to speciate of arsenic (III) and (V) in drinking water. This methodology was used to analyze water samples collectioned from the study of arsenic removal by two technologies, reverse osmosis membrane filtration and chemical coagulation/ filtration in pilot scale in anticipation of EPA=s new arsenic drinking water standard of 10 µg/L takes effect 2006. This EPA treatment technology project was to collect data on the performance of two existing water treatment processes to remove arsenic on pilot scale. Total arsenic concentrations were reduced by reverse osmosis from an average 60 µg/L in the source water to less than 1 µg/L, and chemical coagulation reduced total arsenic from an average 60 µg/L to 4 µg/L. The work reported here will focus on obtaining accurate readings for arsenic valence states (III) and (V), given the Edwards [17] method for arsenic speciation. Separation of arsenic As(III) and As(V) by speciation in field samples, was performed using an anion exchange resin column. The chloride interferences that affect the determination of 75Arsenic from chloride (35 isotope) molecular species (40Ar35Cl), were corrected using chloride measurements in all samples using equation: [75As(corr)] = [75As] - 3.127 × {[40Ar37Cl] - 0.815 [82Se]}. The use of sulfuric acid in the preservation procedure created interferences with ICP-MS in the range one ěg/L of arsenic. The problem of interference in determination of isotope 75As is due to sulfur 34S isotope which is present in sulfate. The (34S isotope, 4.21%) forms the polyatomic species (mass 75) (40Ar34S1H) and species (mass 74) (40Ar34S) which interferes with the determination of 75As isotope. The method detection limit, MDL, for arsenic for ICP-MS was determined to be 0.1 µg/L. Our spiked matrix recoveries, spiked blank samples, and reference materials deviate only a few percents from the listed true values.

2

Arsenic speciation in marine sediment samples from the 26.12.2004 tsunami area in Thailand

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Kozak L. , Niedzielski P.

Polish Journal of Environmental Studies

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2009

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tom 18

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nr 1

87-92

EN

Our paper reports results of speciation analysis of arsenic(III) and (V) in the exchangeable fraction of the marine sediments from the Andaman Sea. The sediments were collected from the coastal zone at the coast of Thailand affected by the 2004 tsunami waves. The samples were extracted with phosphate buffer and then subjected to determination of inorganic species of arsenic by HPLC-HG-AAS. A correlation between the contents of arsenic and grain size of the sediments was found. Higher content of As(III) established in fine grain fraction of the sediment can suggest its deposition by tsunami.

3

Neurological and neurophysiological examinations of workers exposed to arsenic levels exceeding hygiene standards

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Sińczuk-Walczak H. , Janasik B. M. , Trzcinka-Ochocka M. , Stanisławska M. , Szymczak M. , Hałatek T. , Walusiak-Skorupa J.

International Journal of Occupational Medicine and Environmental Health

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2014

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tom 27

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nr 6

1013-1025

EN

Objectives: The assessment of the neurotoxic effect of arsenic (As) and its inorganic compounds is still the subject of interest due to a growing As application in a large array of technologies and the need to constantly verify the principles of prevention and technological parameters. The aim of this study was to determine the status of the nervous system (NS) in workers exposed to As at concentrations exceeding hygiene standards (Threshold Limit Values (TLV) – 10 μg/m³, Biological Exposure Index (BEI) – 35 μg/l) and to analyze the relationship between the NS functional state, species of As in urine and As levels in the workplace air. Material and Methods: The study group comprised 21 men (mean age: 47.43±7.59) employed in a copper smelting factory (mean duration of employment: 22.29±11.09). The control group comprised 16 men, matched by age and work shifts. Arsenic levels in the workplace air (As-A) ranged from 0.7 to 92.3 μg/m³; (M = 25.18±28.83). The concentration of total arsenic in urine (Astot-U) ranged from 17.35 to 434.68 μg/l (M = 86.82±86.6). Results: Syndrome of peripheral nervous system (PNS) was manifested by extremity fatigue (28.6%), extremity pain (33.3%) and paresthesia in the lower extremities (33.3%), as well as by neuropathy-type mini-symptoms (23.8%). Electroneurographic (ENeG) tests of peroneal nerves showed significantly decreased response amplitude with normal values of motor conduction velocity (MCV). Stimulation of sural nerves revealed a significantly slowed sensory conduction velocity (SCV) and decreased sensory potential amplitude. Neurophysiological parameters and the results of biological and environmental monitoring showed a relationship between $\text{As}^\text{tot}$, $\text{As}^\text{III}$ (trivalent arsenic), the sum of iAs ($\text{As}^\text{III}+\text{As}^\text{V}$ (pentavalent arsenic))+MMA (monomethylarsonic acid) concentration in urine and As levels in the air. Conclusions: The results of the study demonstrate that occupational exposure to inorganic arsenic levels exceeding hygiene standards (TLV, BEI) generates disorders typical of peripheral neuropathy.

4

Removal of hazardous metals from groundwater by reserve osmosis

63%

Pawlak Z. , Zak S. , Zablocki L.

Polish Journal of Environmental Studies

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2006

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tom 15

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nr 4

EN

This EPA treatment technology project was designed to collect data on the performance of existing water treatment processes in order to remove arsenic on pilot-scale. Our paper contains verification testing of the reverse osmosis membrane module conducted over a 30-day period at the Spiro Tunnel Bulkhead water (Park City, Utah, USA), which is considered to be a ground water. The total arsenic concentration in the feedwater averaged 60 ppb during the test period and was reduced to an average of 1 ppb in the treated (permeate) water. The work reported here focused on obtaining accurate readings for arsenic valence states (III) and (V), using an anion exchange resin column. The dominant arsenic species in the abandoned silver mine tunnel feedwater was As(V). Results of analysis showed that 70% of the arsenic present in the feed- water was in dissolved form. Arsenic speciation for valence states (III) and (V) showed that arsenic (V) represented 76% of the dissolved arsenic in the source water. The method detection limit (MDL) for arsenic using ICP-MS was determined to be 0.1 ppb. Our matrix spiked recovery, spiked blank samples and reference materials deviated only a few percentage points from the listed true values.

5

The mobility of arsenic and its species in selected herbs

51%

Jabłońska-Czapla M. , Michalski R. , Nocoń K. , Grygoyć K.

Archives of Environmental Protection

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2019

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tom Vol. 45, no. 3

86--98

EN

The aim of the study was verification of the response of chamomile (Matricaria recutita (L.) Rauschert), peppermint (Mentha x piperita) lemon balm (Melissa officinalis L.), and sage (Salvia officinalis L.) on the elevated contents of inorganic As species in soils. The ability of herbs to accumulate arsenic was tested in pot experiment in which soils were contaminated by As(III) and As(V). The As(III), As(V), AB (arsenobetaine), MMA (monomethylarsonic acid) and DMA (dimethylarsinic acid) ions were successfully separated in the Hamilton PRP-X100 column with high performance-liquid chromatography-inductively coupled plasma-mass spectrometry (HPLC-ICP-MS) techniques. The study examined total arsenic contents in soil and plants, as well as the mobility of the arsenic species from the soil into the studied plants. Peppermint demonstrated the highest arsenic concentration and phytoaccumulation among studied plants. The sequential chemical extraction showed that arsenic in the contaminated soil was mainly related to the oxide and organic-sulfi de fractions. The results showed that the oxidized arsenic form had a greater ability to accumulate in herbs and was more readily absorbed from the substrate by plants. Research has shown that soil contaminated with As(III) or As(V) has different effects on the arsenic content in plants. The plant responses to strong environmental pollution varied and depended on their type and the arsenic species with which the soil was contaminated. In most cases it resulted in the appearance of the organic arsenic derivatives.

PL

Celem badań było sprawdzenie tolerancji rumianku (Matricaria recutita (L.) Rauschert), mięty pieprzowej (Mentha x piperita), melisy lekarskiej (Melissa officinalis L.) i szałwii (Salvia officinalis L.) na zwiększoną zawartość nieorganicznych form jonowych arsenu w glebie. Zdolność ziół do akumulacji arsenu została przetestowana w doświadczeniu wazonowym, w którym gleby były zanieczyszczone przez As(III) lub As(V). Formy specjacyjne arsenu: As(III), As(V), AB (arsenobetaina), MMA (kwas monometylowy) i DMA (kwas dimetylowy) rozdzielono na kolumnie Hamilton PRP-X100 za pomocą wysokosprawnej chromatografi i cieczowej połączonej ze spektrometrią mas z plazmą wzbudzoną indukcyjnie (HPLC-ICP-MS). W pracy zbadano zawartość arsenu w glebie i ziołach, a także mobilność form arsenu z gleby do badanych roślin zielnych. Mięta charakteryzowała się największym stopniem fitoakumulacji i stężenia arsenu wśród badanych roślin. Sekwencyjna ekstrakcja chemiczna wykazała, że arsen w zanieczyszczonej glebie był głównie związany z frakcjami tlenkowymi i siarczkowo-organicznymi. Wyniki pokazały również, że utleniona forma arsenu miała większą zdolność do akumulacji w ziołach i była łatwiej absorbowana z podłoża przez badane rośliny. Badania wykazały, że odpowiedź roślin na stres arsenowy była charakterystyczna dla danego gatunku i zróżnicowana w zależności od formy arsenu, którym zanieczyszczono glebę. W większości przypadków skutkowało to pojawieniem się organicznych pochodnych arsenu.