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Addition of selenium to beef cattle given a selenium-deficient diet.

https://arctichealth.org/en/permalink/ahliterature65590
Source
Zentralbl Veterinarmed A. 1985 Jun;32(6):428-32
Publication Type
Article
Date
Jun-1985

The effect of single, peroral doses of selenium in beef cows and suckling calves.

https://arctichealth.org/en/permalink/ahliterature65589
Source
Zentralbl Veterinarmed A. 1985 Jun;32(6):433-6
Publication Type
Article
Date
Jun-1985

The microbial impact on the sorption behaviour of selenite in an acidic, nutrient-poor boreal bog.

https://arctichealth.org/en/permalink/ahliterature272040
Source
J Environ Radioact. 2015 Sep;147:85-96
Publication Type
Article
Date
Sep-2015
Author
M. Lusa
M. Bomberg
H. Aromaa
J. Knuutinen
J. Lehto
Source
J Environ Radioact. 2015 Sep;147:85-96
Date
Sep-2015
Language
English
Publication Type
Article
Keywords
Adsorption
Aerobiosis
Anaerobiosis
Bacteria - metabolism
Finland
Selenious Acid - metabolism
Selenium Radioisotopes - metabolism
Soil Pollutants, Radioactive - metabolism
Water Pollutants, Radioactive - metabolism
Wetlands
Abstract
(79)Se is among the most important long lived radionuclides in spent nuclear fuel and selenite, SeO3(2-), is its typical form in intermediate redox potential. The sorption behaviour of selenite and the bacterial impact on the selenite sorption in a 7-m-deep profile of a nutrient-poor boreal bog was studied using batch sorption experiments. The batch distribution coefficient (Kd) values of selenite decreased as a function of sampling depth and highest Kd values, 6600 L/kg dry weight (DW), were observed in the surface moss and the lowest in the bottom clay at 1700 L/kg DW. The overall maximum sorption was observed at pH between 3 and 4 and the Kd values were significantly higher in unsterilized compared to sterilized samples. The removal of selenite from solution by Pseudomonas sp., Burkholderia sp., Rhodococcus sp. and Paenibacillus sp. strains isolated from the bog was affected by incubation temperature and time. In addition, the incubation of sterilized surface moss, subsurface peat and gyttja samples with added bacteria effectively removed selenite from the solution and on average 65% of selenite was removed when Pseudomonas sp. or Burkholderia sp. strains were used. Our results demonstrate the important role of bacteria for the removal of selenite from the solution phase in the bog environment, having a high organic matter content and a low pH.
PubMed ID
26048060 View in PubMed
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Sorption and speciation of selenium in boreal forest soil.

https://arctichealth.org/en/permalink/ahliterature282812
Source
J Environ Radioact. 2016 Nov;164:220-231
Publication Type
Article
Date
Nov-2016
Author
Mervi Söderlund
Juhani Virkanen
Stellan Holgersson
Jukka Lehto
Source
J Environ Radioact. 2016 Nov;164:220-231
Date
Nov-2016
Language
English
Publication Type
Article
Keywords
Adsorption
Finland
Selenic Acid
Selenious Acid
Selenium - analysis - chemistry
Soil - chemistry
Soil Pollutants - analysis - chemistry
Taiga
Abstract
Sorption and speciation of selenium in the initial chemical forms of selenite and selenate were investigated in batch experiments on humus and mineral soil samples taken from a 4-m deep boreal forest soil excavator pit on Olkiluoto Island, on the Baltic Sea coast in southwestern Finland. The HPLC-ICP-MS technique was used to monitor any possible transformations in the selenium liquid phase speciation and to determine the concentrations of selenite and selenate in the samples for calculation of the mass distribution coefficient, Kd, for both species. Both SeO3(2-) and SeO4(2-) proved to be resistant forms in the prevailing soil conditions and no changes in selenium liquid phase speciation were seen in the sorption experiments in spite of variations in the initial selenium species, incubation time or conditions, pH, temperature or microbial activity. Selenite sorption on the mineral soil increased with time in aerobic conditions whilst the opposite trend was seen for the anaerobic soil samples. Selenite retention correlated with the contents of organic matter and weakly crystalline oxides of aluminum and iron, solution pH and the specific surface area. Selenate exhibited poorer sorption on soil than selenite and on average the Kd values were 27-times lower. Mineral soil was more efficient in retaining selenite and selenate than humus, implicating the possible importance of weakly crystalline aluminum and iron oxides for the retention of oxyanions in Olkiluoto soil. Sterilization of the soil samples decreased the retention of selenite, thus implying some involvement of soil microbes in the sorption processes or a change in sample composition, but it produced no effect for selenate. There was no sorption of selenite by quartz, potassium feldspar, hornblende or muscovite. Biotite showed the best retentive properties for selenite in the model soil solution at about pH 8, followed by hematite, plagioclase and chlorite. The Kd values for these minerals were 18, 14, 8 and 7 L/kg, respectively. It is proposed that selenite sorption is affected by the structural Fe(II) in biotite, which is capable of inducing the reduction of SeO3(2-) to Se(0). Selenite probably forms a surface complex with Fe(III) atoms on the surface of hematite, thus explaining its retention on this mineral. None of the minerals retained selenate to any extent.
PubMed ID
27521902 View in PubMed
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