7/30/2019 Determination of Total and Hexavalent Chromium in Bile

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Determination of total and hexavalent chromium in bile ...

Environmental Research

Determination of total and hexavalent chromium in bile after intravenous administration of

potassium dichromate in ratsEnvironmental Research, Volume 37, Issue 2,August 1985, Pages 490-496

Alessandro Cavalleri, Claudio Minoia, Plinio Richelmi, Carla Baldi, Guiseppina Micoli

Abstract

Total and hexavalent chromium were measured in bile samples obtained from cannulated bile

ducts of male rats iv administered with potassium dichromate at various doses corresponding to

0.1, 0.5, and 1 mg of chromium. The evaluation of the hexavalent form was performed by

separation with a liquid anion exchanger and electrothermal atomization-atomic absorption

spectrophotometric determination. Within 2 hr 1.352.23% of the chromium injected wasrecovered in bile as total chromium, the hexavalent form accounting for less than 1% of the total

chromium collected, which seems almost entirely excreted as trivalent chromium. Since Cr(VI)

administered iv was quickly reduced to Cr(III) in blood, the possibility exists for chromium in

trivalent form to penetrate into the liver cells and to be excreted in the bile, possibly by binding

to a carrier such as the low-molecular-weight substance described by Yamamoto et al. (A.

Yamamoto, O. Wada, and T. Ono, Toxicol. Appl. Pharmacol., 59, 515, 1981).

PDF (369 K)

Effect of pH on rejection of hexavalent chromium by nan...

Desalination

Effect of pH on rejection of hexavalent chromium by nanofiltrationDesalination, Volume 219, Issues 1-3, 25 January 2008, Pages 171-178

M. Muthukrishnan, B.K. Guha

Abstract

Removal of hexavalent chromium (Cr

+6

) was carried out with different nanofiltration (NF)membranes for varying concentration and pH of the membrane feed solution. Two

membranes were used for this investigation: one high rejection membrane (NFI) and the other

a low rejection membrane (NFII). The percent rejection of chromium was found to increase

with the increase of feed solution pH. It has been observed that the effect of feed

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7/30/2019 Determination of Total and Hexavalent Chromium in Bile

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concentration on the percent rejection was quite low, but the nature of effect varies with the

pH of the solution with a transition happening at above pH 7.0. The rejection was observed to

increase with increasing in concentration for feed pH below 7.0, whereas at higher pH a

reverse trend occurs with lowering of rejection for higher feed concentration. The permeateflux was found to be lower at higher feed concentration, but varied only marginally with

change in pH value. UV-spectrograph of the permeate solution at different pH value was

carried out to determine the nature of the ionic species of chromium present in the system.

Results show that the variation of rejection at different pH is due to the nature of ionic

component present at the specific pH. The role of feed solution pH for membrane separation

of chromium has been explained with the help of this spectrograph.

PDF (346 K)

Determination of atmospheric concentrations of inorgani...

Journal of Chromatography A

Determination of atmospheric concentrations of inorganic anions by ion chromatography

following ultrasonic extraction

Journal of Chromatography A, Volume 1094, Issues 1-2, 11 November 2005, Pages 118-121

Seyed Mortaza Talebi, Mohammad Abedi

AbstractThe capability of the suppressed conductometric detection ion chromatography (IC) was

investigated for the separation and determination of inorganic anions (F, Cl

, NO3

and SO4

2)

in standard reference materials SRM-1648 urban particulate matter following ultrasonic

extraction. The effects of the cationic surfactant (SDS) and the anionic surfactant (CTAB) on

ultrasonic extraction efficiency of inorganic anions from complex matrix of airborne

particulate matter were investigated. The results showed that surfactant can enhance the

extraction efficiency. Finally, the concentrations of inorganic anions in the atmosphere of the

city of Isfahan were determined. The results showed a trend of SO42

> NO3

> Cl

> F

.

PDF (139 K)

Sensitivity of estuarine phytoplankton to hexavalent ch...

Estuarine, Coastal and Shelf Science

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er=2512477&_orig=article&_coverDate=11/11/2005&_sk=989059998&view=c&wchp=dGLbVzb-zSkzV&md5=f0be1b618c05062b1394e514217201e0&ie=/sdarticle.pdfhttp://www.sciencedirect.com/science?_ob=MImg&_imagekey=B6TFX-4R94WFD-K-1&_cdi=5238&_user=2512477&_orig=article&_coverDate=01/25/2008&_sk=997809998&view=c&wchp=dGLbVzb-zSkzV&md5=420e3551724ecd9dcb1901a2467bf06c&ie=/sdarticle.pdfhttp://www.sciencedirect.com/science?_ob=MImg&_imagekey=B6TG8-4GYNY75-4-C&_cdi=5248&_user=2512477&_orig=article&_coverDate=11/11/2005&_sk=989059998&view=c&wchp=dGLbVzb-zSkzV&md5=f0be1b618c05062b1394e514217201e0&ie=/sdarticle.pdfhttp://www.sciencedirect.com/science?_ob=MImg&_imagekey=B6TFX-4R94WFD-K-1&_cdi=5238&_user=2512477&_orig=article&_coverDate=01/25/2008&_sk=997809998&view=c&wchp=dGLbVzb-zSkzV&md5=420e3551724ecd9dcb1901a2467bf06c&ie=/sdarticle.pdfhttp://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6WDV-4DV0MVF-P3&_user=2512477&_origUdi=B6WDS-485XGY3-2&_fmt=high&_coverDate=08%2F31%2F1983&_rdoc=1&_orig=article&_acct=C000027478&_version=1&_urlVersion=0&_userid=2512477&md5=11a0d0163fc9c81f5b9d6a93315dfea9http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6WDV-4DV0MVF-P3&_user=2512477&_origUdi=B6WDS-485XGY3-2&_fmt=high&_coverDate=08%2F31%2F1983&_rdoc=1&_orig=article&_acct=C000027478&_version=1&_urlVersion=0&_userid=2512477&md5=11a0d0163fc9c81f5b9d6a93315dfea9http://www.sciencedirect.com/science?_ob=MImg&_imagekey=B6TG8-4GYNY75-4-C&_cdi=5248&_user=2512477&_orig=article&_coverDate=11%2F11%2F2005&_sk=989059998&view=c&wchp=dGLbVzb-zSkzV&md5=f0be1b618c05062b1394e514217201e0&ie=/sdarticle.pdfhttp://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6TG8-4GYNY75-4&_user=2512477&_coverDate=11%2F11%2F2005&_rdoc=1&_fmt=high&_orig=article&_cdi=5248&_sort=v&_st=4&_docanchor=&view=c&_ct=2603&_acct=C000027478&_version=1&_urlVersion=0&_userid=2512477&md5=d85971e479f84db41c18dd2314933c0fhttp://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6TG8-4GYNY75-4&_user=2512477&_coverDate=11%2F11%2F2005&_rdoc=1&_fmt=high&_orig=article&_cdi=5248&_sort=v&_st=4&_docanchor=&view=c&_ct=2603&_acct=C000027478&_version=1&_urlVersion=0&_userid=2512477&md5=d85971e479f84db41c18dd2314933c0fhttp://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6TG8-4GYNY75-4&_user=2512477&_origUdi=B6WDS-485XGY3-2&_fmt=high&_coverDate=11%2F11%2F2005&_rdoc=1&_orig=article&_acct=C000027478&_version=1&_urlVersion=0&_userid=2512477&md5=5f9c3e6f98fde2ae83057d6fb6f3874dhttp://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6TG8-4GYNY75-4&_user=2512477&_origUdi=B6WDS-485XGY3-2&_fmt=high&_coverDate=11%2F11%2F2005&_rdoc=1&_orig=article&_acct=C000027478&_version=1&_urlVersion=0&_userid=2512477&md5=5f9c3e6f98fde2ae83057d6fb6f3874dhttp://www.sciencedirect.com/science?_ob=MImg&_imagekey=B6TFX-4R94WFD-K-1&_cdi=5238&_user=2512477&_orig=article&_coverDate=01%2F25%2F2008&_sk=997809998&view=c&wchp=dGLbVzb-zSkzV&md5=420e3551724ecd9dcb1901a2467bf06c&ie=/sdarticle.pdf

7/30/2019 Determination of Total and Hexavalent Chromium in Bile

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Sensitivity of estuarine phytoplankton to hexavalent chromiumEstuarine, Coastal and Shelf Science, Volume 17, Issue 2,August 1983, Pages 181-187

Bruce E. Frey, G. Fritz Riedel, Ann E. Bass, Lawrence F. Small

Abstract

Experiments were conducted in which we tested the effects of hexavalent chromium on both

natural assemblages of phytoplankton and cultures ofThalassiosira pseudonana clone 3H.

Water was collected from various locations in Yaquina Bay, Oregon, with salinities ranging

from 325 to 003. A variety of nutrient regimes were tested by adding major nutrients

and micro-nutrients, and/or stripping micro-nutrients with activated carbon. In one high

salinity experiment, chromium was stimulatory, as were micro-nutrient additions. In other high

and medium salinity experiments, chromium was neither stimulatory nor inhibitory, at levels

up to 19 mole l1

Cr. There was, however, slight inhibition of growth at 190 mole l1

Cr,

due specifically to inhibition ofSkeletonema costatum. In our freshwater experiments,

chromium was very inhibitory at 19 mole l1

Cr, and slightly inhibitory at 019 mole l1

Cr. Species inhibited by chromium were Surirella ovata, Detonula confervacea, and Cyclotella

sp. Experiments were conducted with T. pseudonana grown over a wide range of salinities.

Chromium was found to be very inhibitory in freshwater and became progressively less toxic

as the salinity increased. Most inhibition was neutralized by a salinity of 21.

PDF (507 K)

In vivo production of hexavalent chromium

Biomaterials

In vivo production of hexavalent chromium

Biomaterials, Volume 5, Issue 4,July 1984, Pages 244-245

G.T. Rogers

Abstract

Surgical implants which contain chromium result in increasedin vivoconcentrations. The

oxidation chemistry of this reaction is considered.

PDF (199 K)

Abstract

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overDate=07%2F31%2F1984&_sk=999949995&view=c&wchp=dGLbVzb-zSkzV&md5=19eb62116bbd7da69c84d5ee21c41916&ie=/sdarticle.pdfhttp://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6TWB-48HRK0D-KD&_user=2512477&_coverDate=07%2F31%2F1984&_rdoc=1&_fmt=high&_orig=article&_cdi=5558&_sort=v&_st=4&_docanchor=&view=c&_ct=2603&_acct=C000027478&_version=1&_urlVersion=0&_userid=2512477&md5=a84acff389e0e3b59492243a8cba13cehttp://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6TWB-48HRK0D-KD&_user=2512477&_origUdi=B6WDS-485XGY3-2&_fmt=high&_coverDate=07%2F31%2F1984&_rdoc=1&_orig=article&_acct=C000027478&_version=1&_urlVersion=0&_userid=2512477&md5=5ffb03933ec65c3ca906ff33593333c1http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6TWB-48HRK0D-KD&_user=2512477&_origUdi=B6WDS-485XGY3-2&_fmt=high&_coverDate=07%2F31%2F1984&_rdoc=1&_orig=article&_acct=C000027478&_version=1&_urlVersion=0&_userid=2512477&md5=5ffb03933ec65c3ca906ff33593333c1http://www.sciencedirect.com/science?_ob=MImg&_imagekey=B6WDV-4DV0MVF-P3-1&_cdi=6776&_user=2512477&_orig=article&_coverDate=08%2F31%2F1983&_sk=999829997&view=c&wchp=dGLbVzb-zSkzV&md5=b7ca0c70b5af5289401872086ccce5a4&ie=/sdarticle.pdfhttp://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6WDV-4DV0MVF-P3&_user=2512477&_coverDate=08%2F31%2F1983&_rdoc=1&_fmt=high&_orig=article&_cdi=6776&_sort=v&_st=4&_docanchor=&view=c&_ct=2603&_acct=C000027478&_version=1&_urlVersion=0&_userid=2512477&md5=29f888af049cb3b86e3ac42d21554a9a

7/30/2019 Determination of Total and Hexavalent Chromium in Bile

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Airborne particulate matter was collected from the atmosphere of the city of Isfahan by a high-

volume air sampler. Determination of the concentration of total chromium was carried out

by graphite furnace atomic absorption spectrometry after acid digestion. The determination of

hexavalent chromium was carried out by ion chromatography following the collection of

Cr(vi) in an impinger. Day-to-day variations in concentrations of total and hexavalent

chromium were investigated and an excellent similarity was found between them. Atmospheric

levels of total and hexavalent chromium were also investigated in different months of the

year, and maximum concentrations were found in October.

Article Outline

1. Introduction

2. Experimental2.1. Collection of samples

2.2. Digestion of airborne particulate matter

2.3. Determination of total chromium concentration

3. Results and discussion

References

1. Introduction

Chromium is released into the atmosphere from both natural and anthropogenic sources. The

major sources of this element in the urban atmosphere are anthropogenic sources, including the

production of iron and steel and, in a smaller proportion, the combustion of fossil fuels

(Demuynk et al., 1979). Chromium in the atmosphere is associated with airborne particulate

matter and is ubiquitous in the lower atmosphere ( Dobbins, 1979; Lum et al., 1982).

Chromium exists in the environment predominantly in two physicochemical forms: Cr(iii) and

Cr(vi). The toxicity of their compounds differs greatly. Trivalent-state chromium is necessary

for the maintenance of a normal glucose tolerance factor, while Cr(vi) is toxic and carcinogen

(Padarauskkas and Schwedt, 1995). Determination of the total concentration of chromium

in the urban atmosphere is not sufficient to evaluate the hazards of this element. However,

determination of the atmospheric concentration of hexavalent chromium is important

because of its high toxicity, continuous nature of exposures and also the size of the population at

risk, especially in metropolitan areas ( Rochi and Alforque, 1990). Chromium (vi) is less stable

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