Artykuły w czasopismach na temat „Iodine”
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1
Markova, Ekaterina О., Dmitry A. Nekrasov, Michael Yu Dyakov i Arkady A. Danilov. "Determination of the content of iodine, iodides and iodates in food products". Izvestiya of Saratov University. Chemistry. Biology. Ecology 22, nr 4 (15.12.2022): 373–81. http://dx.doi.org/10.18500/1816-9775-2022-22-4-373-381.
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Currently iodine deficiency diseases are one of the most important medical and social problems. In this regard, the purpose of the study is to determine the content of iodine, iodides, iodates in iodized salt, drinking and mineral water, seaweed, to determine the stability of the iodine content in salt. For the qualitative determination of iodides and iodates ions in salts and molecular iodine in seaweed, an iodine starch reaction has been carried out. The presence of iodide ions in iodized water has been determined by reaction with silver nitrate and chlorine water, the iodine released has been extracted with chloroform. Quantitative determination of iodine in salt has been carried out by the titrimetric method, in water – by colorimetric method, in seaweed – by gravimetric method with subsequent titration. The study has found that iodized salt contains iodine in the form of potassium iodate, in an amount of 18.65 μg / g of elemental iodine, kelp contains molecular iodine in the amount of 8.12 μg / g of elemental iodine, and iodized water contains potassium iodide in the amount of 0.327 μg / ml of elemental iodine. The study has proved that over time, the amount of iodine in the salt iodized with potassium iodate decreases after a month by 5.6 times. In order to comply with the daily rate of iodine intake, it is necessary to include in your diet about 9.7 g of iodized salt, which exceeds the daily norm of its consumption in 5 g. In this regard, it is recommended to use iodized salt (not more than 5 g) or iodized water (0.7 L of water) or kelp (18.47 g) as a prevention of iodine deficiency.
2
Ilin, Alexander, i Armen Nersesyan. "Toxicology of iodine: A mini review". Archive of Oncology 21, nr 2 (2013): 65–71. http://dx.doi.org/10.2298/aoo1302065i.
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Iodine is necessary for all living organisms. Deficiency of iodine in the organism leads to various diseases (including mental) and increased rates of cancer. It is well known that one third of the world?s population lived in iodine-deficient areas. At present time, the primary intervention for preventing iodine deficiency disorders worldwide is through the iodization of salt. The two most common types of fortificant used to iodize salt are potassium iodide and potassium iodate. Iodine-containing compounds are also widely used in clinical medicine as a highly effective topical antimicrobial agent that has been used clinically in the treatment of wounds. Hence, the genetic toxicology of iodine and iodine-containing compounds is very essential topic. In this literature review are analyzed the data concerning genetic toxicology and the influence of these compounds on tumor rates in epidemiological and experimental studies.
3
Anderson, Kim A., i Peter Markowski. "Speciation of Iodide, Iodine, and Iodate in Environmental Matrixes by Inductively Coupled Plasma Atomic Emission Spectrometry Using in situ Chemical Manipulation". Journal of AOAC INTERNATIONAL 83, nr 1 (1.01.2000): 225–30. http://dx.doi.org/10.1093/jaoac/83.1.225.
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Abstract Dissolved iodine, iodide, and iodate are determined in environmental matrixes by in situ chemical manipulation and inductively coupled plasma atomic emission spectrometry (ICPAES). The method uses equipment commonly available to most laboratories involved in environmental inorganic analysis. Total dissolved iodine, iodide, and iodate are determined by ICPAES using iodine vapor generation. Total iodine is determined directly by ICPAES after filtration. Total dissolved iodide (I−) is oxidized in situ to iodine by the addition of sodium nitrite in sulfuric acid in a simplified continuous flow manifold. Iodate is determined by prereduction at the instrument before analysis by the in situ oxidation ICPAES procedure. A standard nebulizer produces the gas–liquid separation of the total iodine, which is then quantified by ICPAES at 206.16 nm. The instrument detection limit for the iodine analysis was 0.04 μg/mL. Recoveries from seawater, saltwater, and freshwater standard reference materials ranged from 85 to 118% and averaged 98%. For samples containing both iodine and iodide, the total is determined with in situ oxidation, iodine is determined without the oxidizing reagents, and iodide is calculated from the difference. For samples containing all 3 species, pre-reduction is used and the iodine and iodide concentrations are subtracted for quantitation of iodate. The analysis is selective for these 3 species (I−, I2, and IO−3). A group of 20–30 samples may be analyzed and quantitated for all 3 individual, commonly occurring iodide species in less than 1 h. The procedure is considerably faster than any other reported techniques. This method is especially well-suited to the analysis of small environmental samples.
4
Gayduk, Olga V. "SPECTROPHOTOMETRIC DETERMINATION OF IODATE IN IODIDES OF ALKALINE METALS". Industrial laboratory. Diagnostics of materials 85, nr 4 (15.05.2019): 17–21. http://dx.doi.org/10.26896/1028-6861-2019-85-4-17-21.
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Conditions for interaction of the iodate ions with iodide and methylene blue as a chromogenic reagent were studied. The interaction of iodate with an excess of iodide depends on the medium acidity. In dilute acids, the reaction of IO3 with Г is accompanied with a release of iodine which oxidizes the dye. The observed weakening of the color which is proportional to the concentration of iodate ions in the solution, results from the oxidative destruction of methylene blue. Spectra of methylene blue, conditions of the redox interaction, as well as the effect of the solution acidity and reagent concentration on the completeness of the reaction were studied. The light absorption of the solutions was measured at a wavelength of 664 nm. The reaction of the free iodine formation is rapid and quantitative at pH 4 - 5 . The desired acidity of the medium was attained using 1 M solution of acetic acid. The optimal concentration of methylene blue was determined. The results of the study formed a base for developing a technique of iodate ion determination in iodides of alkaline metals. The analyzed solutions were prepared with addition of sodium acetate to prevent iodide oxidation by atmospheric oxygen. To eliminate the interfering effect of Fe (III), sodium pyrophosphate (which should be introduced after acidification of the solution and isolation of iodine) was used. The accuracy of the technique was proved in spike tests on the model solutions and real samples by the method of sample weight variation. The developed technique was tested in determination of the iodate ions in cesium and sodium iodides. The relative standard deviation does not exceed 15%. The sensitivity of the developed technique is 10 times higher compared to the technique based on the formation of an iodine-starch complex.
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Baker, Alex R., i Chan Yodle. "Measurement report: Indirect evidence for the controlling influence of acidity on the speciation of iodine in Atlantic aerosols". Atmospheric Chemistry and Physics 21, nr 17 (2.09.2021): 13067–76. http://dx.doi.org/10.5194/acp-21-13067-2021.
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Abstract. The speciation of soluble iodine and major-ion composition were determined in size-fractionated aerosols collected during the AMT21 cruise between Avonmouth, UK, and Punta Arenas, Chile, in September–November 2011. The proportions of iodine species (iodide, iodate and soluble organic iodine (SOI)) varied markedly between size fractions and with the extent to which the samples were influenced by pollutants. In general, fine mode aerosols (< 1 µm) contained higher proportions of both iodide and SOI, while iodate was the dominant component of coarse (< 1 µm) aerosols. The highest proportions of iodate were observed in aerosols that contained (alkaline) unpolluted sea spray or mineral dust. Fine mode samples with high concentrations of acidic species (e.g. non-sea-salt sulfate) contained very little iodate and elevated proportions of iodide and SOI. These results are in agreement with modelling studies that indicate that iodate can be reduced under acidic conditions and that the resulting hypoiodous acid (HOI) can react with organic matter to produce SOI and iodide. Further work that investigates the link between iodine speciation and aerosol pH directly, as well as studies on the formation and decay of organo-iodine compounds under aerosol conditions, will be necessary before the importance of this chemistry in regulating aerosol iodine speciation can be confirmed.
6
Gilfedder, B. S., S. Lai, M. Petri, H. Biester i T. Hoffmann. "Iodine speciation in rain, snow and aerosols and possible transfer of organically bound iodine species from aerosol to droplet phases". Atmospheric Chemistry and Physics Discussions 8, nr 2 (22.04.2008): 7977–8008. http://dx.doi.org/10.5194/acpd-8-7977-2008.
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Abstract. Iodine oxides, such as iodate, should theoretically be the only stable sink species for iodine in the troposphere. However, field observations have increasingly found very little iodate and significant amounts of iodide and organically bound iodine in precipitation and aerosols. The aim of this study was to investigate iodine speciation, including the organic fraction, in rain, snow, and aerosols in an attempt to further clarify aqueous phase iodine chemistry. Diurnal aerosol samples were taken with a 5 stage cascade impactor and a virtual impactor (PM2.5) from the Mace Head research station, Ireland, during summer 2006. Rain was collected from Australia, New Zealand, Patagonia, Germany, Ireland, and Switzerland while snow was obtained from Greenland, Germany, Switzerland, and New Zealand. All samples were analysed for total iodine by inductively coupled plasma mass spectrometry (ICP-MS) and speciation was determined by coupling an ion chromatography unit to the ICP-MS. Total iodine in the aerosols from Mace Head gave a median concentration of 50 pmol m−3 of which the majority was associated with the organic fraction (median day: 91±7%, night: 94±6% of total iodine). Iodide exhibited higher concentrations than iodate (median 5% vs. 0.8% of total iodine), and displayed significant enrichment during the day compared to the night. Interestingly, up to 5 additional, presumably anionic organic peaks were observed in all IC-ICP-MS chromatograms, composing up to 15% of the total iodine. Organically bound iodine was also the dominant fraction in all rain and snow samples, with lesser amounts of iodide and iodate (iodate was particularly low in snow). Two of the same unidentified peaks found in aerosols were also observed in precipitation from both Southern and Northern Hemispheres, suggesting that these species are transferred from the aerosol phase into precipitation. It is suggested that organo-I is formed by reactions between HOI and organic matter derived from the ocean surface layer. This may then photolytically decompose to give iodide and the unidentified species. The data in this study show that iodine oxides are the least abundant species in rain, snow, and aerosols and therefore considerably more effort is required on aqueous phase iodine chemistry for a holistic understanding of the iodine cycle.
7
Takayanagi, Kazufumi, i Daniel Cossa. "Behaviour of dissolved iodine in the upper St. Lawrence Estuary". Canadian Journal of Earth Sciences 22, nr 4 (1.04.1985): 644–46. http://dx.doi.org/10.1139/e85-067.
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The concentrations of dissolved total iodine and iodate were determined in the water samples collected from various depths at 14 stations located in the upper St. Lawrence Estuary. The concentrations of total iodine and iodate ranged from undetectable (< 0.008 μM) to 0.40 μM and from undetectable to 0.36 μM, respectively, and salinities ranged from 0 to 33.9‰. The concentrations of total iodine and iodate increased with increasing salinity, and they correlated linearly with salinity. This implies that both total iodine and iodate behave conservatively in the estuary. The concentration of iodide, calculated as the difference in the concentrations of total iodine and iodate, was low throughout the estuary. Iodate was the major species of dissolved iodine in the upper St. Lawrence Estuary.
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Tietze, S., M. R. St J. Foreman i C. Ekberg. "Synthesis of I-131 labelled iodine species relevant during severe nuclear accidents in light water reactors". Radiochimica Acta 101, nr 10 (październik 2013): 675–80. http://dx.doi.org/10.1524/ract.2013.2070.
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Summary Methods for the small scale synthesis of I-131 labelled iodine species relevant to severe nuclear accidents in light water reactors have been developed. The introduced methods allow the synthesis of impurity free, volatile, inorganic elemental iodine and volatile, organic iodides such as methyl- and ethyl iodide, as well as butyl iodide, chloroiodomethane, allyl iodide and benzyl iodide with ease. The radioactive iodine containing products are sufficiently stable to allow their storage for later use. Due to their volatility the liquid species can be easily converted into gaseous species and thus can be used in research in liquid and gaseous phase. The primary motivation for the development of these synthesis methods is to study the behaviour of volatile iodine species under the conditions of a severe nuclear accident in a light water reactor. Thus, the chemicals involved in the synthesis are chosen in a way to not generate impurities (chlorine and organic solvents) in the products which interfere with competing reactions relevant during a severe nuclear accident. Teknopox Aqua VA epoxy paint, which is used in Swedish light water reactor containments, and its reactions with the produced iodine species are described. The synthesised iodine species undergo chemisorption on paint films. Different to elemental iodine, the organic iodides are non-reactive with copper surfaces. The sorbed iodine species are partly re-released mainly in form of organic iodides and not as elemental iodine when the exposed paint films are heat treated. The partitioning and hydrolysis behaviour of gaseous methyl- and ethyl iodide between containment gas phase and water pools is found to be similar. The methods have been designed to minimise the use of harmful materials and the production of radioactive waste.
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Gilfedder, B. S., M. Petri i H. Biester. "Iodine speciation and cycling in limnic systems: observations from a humic rich headwater lake (Mummelsee)". Biogeosciences Discussions 5, nr 1 (4.01.2008): 25–64. http://dx.doi.org/10.5194/bgd-5-25-2008.
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Abstract. Iodine undergoes several redox changes in the natural environment, existing as iodate, iodide, and covalently bound to organic matter. While considerable attention has been given to iodine speciation and cycling in the marine environment, very little is known about iodine cycling and speciation in terrestrial fresh water systems. Here we show iodine speciation (measured by IC-ICP-MS) data from one year of monthly sampling of a small humic rich lake in the Black Forest (Mummelsee) under varying redox conditions. The aim was to elucidate the seasonal cycles of iodine species in the lake water column and to quantify both inorganic and organic iodine species. A sediment core was also collected for iodine analysis. Total iodine levels in the Mummelsee averaged 1.93±0.3 μg l−1. Organo-I was the dominant species in the lake, making up on average 85±7% of the total iodine. No strong seasonal variation in organo-I was observed, with only small variations occurring in the epi- and hypolimnion. Iodide was scavenged from the epilimnion during the summer and autumn, which could be related to (micro)biological uptake and co-precipitation. This was also suggested by the high iodine levels in the sediment core (av. 11.8±1.7 mg kg −1). In the hypolimnion, a strong flux of iodide was observed from the sediments into the water column during anoxic and hypoxic conditions, observed during the summer, autumn and, in the bottom 2 m, the winter. This iodide flux and is thought to occur during decomposition of biological material. Iodate levels in the epilimnion increased consistently over the year, whereas it was reduced below detection limits in the hypolimnion during low oxygen conditions. The winter partial turnover lead to reintroduction of oxygen into the hypolimnion and the formation of iodate and organo-I, as well as removal of iodide. In conclusions, iodine cycling in the Mummelsee was controlled by organo-I, although redox conditions and perhaps biological activity were also important, particularly in the hypolimnion during stratification.
10
Gilfedder, B. S., S. C. Lai, M. Petri, H. Biester i T. Hoffmann. "Iodine speciation in rain, snow and aerosols". Atmospheric Chemistry and Physics 8, nr 20 (21.10.2008): 6069–84. http://dx.doi.org/10.5194/acp-8-6069-2008.
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Abstract. Iodine oxides, such as iodate, should be the only thermodynamically stable sink species for iodine in the troposphere. However, field observations have increasingly found very little iodate and significant amounts of iodide and soluble organically bound iodine (SOI) in precipitation and aerosols. The aim of this study was to investigate iodine speciation, including the organic fraction, in rain, snow, and aerosols in an attempt to further clarify aqueous phase iodine chemistry. Diurnal aerosol samples were taken with a 5 stage cascade impactor and a virtual impactor (PM2.5) from the Mace Head research station, Ireland, during summer 2006. Rain was collected from Australia, New Zealand, Patagonia, Germany, Ireland, and Switzerland and snow was obtained from Greenland, Germany, Switzerland, and New Zealand. Aerosols were extracted from the filters with water and all samples were analysed for total soluble iodine (TSI) by inductively coupled plasma mass spectrometry (ICP-MS) and iodine speciation was determined by coupling an ion chromatography unit to the ICP-MS. The median concentration of TSI in aerosols from Mace Head was 222 pmol m−3 (summed over all impactor stages) of which the majority was associated with the SOI fraction (median day: 90±4%, night: 94±2% of total iodine). Iodide exhibited higher concentrations than iodate (median 6% vs. 1.2% of total iodine), and displayed significant enrichment during the day compared to the night. Interestingly, up to 5 additional, presumably anionic iodo-organic peaks were observed in all IC-ICP-MS chromatograms, composing up to 15% of the TSI. Soluble organically bound iodine was also the dominant fraction in all rain and snow samples, with lesser amounts of iodide and iodate (iodate was particularly low in snow). Two of the same unidentified peaks found in aerosols were also observed in precipitation from both Southern and Northern Hemispheres. This suggests that these species are transferred from the aerosols into precipitation and that they have either a relatively long lifetime or are rapidly recycled. It is thought that SOI is formed by reactions between HOI or I2 and organic matter derived from the ocean surface layer. SOI may then photolytically decompose to yield iodide and the unidentified species. The data in this study show that iodine oxides are the least abundant species in rain, snow, and aerosols and therefore considerably more effort is required on aqueous phase iodine chemistry for a holistic understanding of the iodine cycle.
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Hepach, Helmke, Claire Hughes, Karen Hogg, Susannah Collings i Rosie Chance. "Senescence as the main driver of iodide release from a diverse range of marine phytoplankton". Biogeosciences 17, nr 9 (7.05.2020): 2453–71. http://dx.doi.org/10.5194/bg-17-2453-2020.
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Abstract. The reaction between ozone and iodide at the sea surface is now known to be an important part of atmospheric ozone cycling, causing ozone deposition and the release of ozone-depleting reactive iodine to the atmosphere. The importance of this reaction is reflected by its inclusion in chemical transport models (CTMs). Such models depend on accurate sea surface iodide fields, but measurements are spatially and temporally limited. Hence, the ability to predict current and future sea surface iodide fields, i.e. sea surface iodide concentration on a narrow global grid, requires the development of process-based models. These models require a thorough understanding of the key processes that control sea surface iodide. The aim of this study was to explore if there are common features of iodate-to-iodide reduction amongst diverse marine phytoplankton in order to develop models that focus on sea surface iodine and iodine release to the troposphere. In order to achieve this, rates and patterns of changes in inorganic iodine speciation were determined in 10 phytoplankton cultures grown at ambient iodate concentrations. Where possible these data were analysed alongside results from previous studies. Iodate loss and some iodide production were observed in all cultures studied, confirming that this is a widespread feature amongst marine phytoplankton. We found no significant difference in log-phase, cell-normalised iodide production rates between key phytoplankton groups (diatoms, prymnesiophytes including coccolithophores and phaeocystales), suggesting that a phytoplankton functional type (PFT) approach would not be appropriate for building an ocean iodine cycling model. Iodate loss was greater than iodide formation in the majority of the cultures studied, indicating the presence of an as-yet-unidentified “missing iodine” fraction. Iodide yield at the end of the experiment was significantly greater in cultures that had reached a later senescence stage. This suggests that models should incorporate a lag between peak phytoplankton biomass and maximum iodide production and that cell mortality terms in biogeochemical models could be used to parameterise iodide production.
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Pechtl, S., G. Schmitz i R. von Glasow. "Modeling iodide – iodate speciation in atmospheric aerosol". Atmospheric Chemistry and Physics Discussions 6, nr 6 (3.11.2006): 10959–89. http://dx.doi.org/10.5194/acpd-6-10959-2006.
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Abstract. The speciation of iodine in atmospheric aerosol is currently poorly understood. Models predict negligible iodide concentrations and accumulation of iodate in aerosol, both of which is not confirmed by recent measurements. We present an updated aqueous phase iodine chemistry scheme for use in atmospheric chemistry models and discuss sensitivity studies with the marine boundary layer model MISTRA. These studies show that iodate can be reduced in acidic aerosol by inorganic reactions, i.e., iodate does not necessarily accumulate in particles. Furthermore, the transformation of particulate iodide to volatile iodine species likely has been overestimated in previous model studies due to negligence of collision-induced upper limits for the reaction rates. However, inorganic reaction cycles still do not seem to be sufficient to reproduce the observed range of iodide – iodate speciation in atmospheric aerosol. Therefore, we also investigate the effects of the recently suggested reaction of HOI with dissolved organic matter to produce iodide. If this reaction is fast enough to compete with the inorganic mechanism, it would not only directly lead to enhanced iodide concentrations but, indirectly via speed-up of the inorganic iodate reduction cycles, also to a decrease in iodate concentrations. Hence, according to our model studies, organic iodine chemistry, combined with inorganic reaction cycles, is able to reproduce observations. The presented chemistry cycles are highly dependent on pH and thus offer an explanation for the large observed variability of the iodide – iodate speciation in atmospheric aerosol.
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Pechtl, S., G. Schmitz i R. von Glasow. "Modelling iodide – iodate speciation in atmospheric aerosol: Contributions of inorganic and organic iodine chemistry". Atmospheric Chemistry and Physics 7, nr 5 (28.02.2007): 1381–93. http://dx.doi.org/10.5194/acp-7-1381-2007.
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Abstract. The speciation of iodine in atmospheric aerosol is currently poorly understood. Models predict negligible iodide concentrations but accumulation of iodate in aerosol, both of which is not confirmed by recent measurements. We present an updated aqueous phase iodine chemistry scheme for use in atmospheric chemistry models and discuss sensitivity studies with the marine boundary layer model MISTRA. These studies show that iodate can be reduced in acidic aerosol by inorganic reactions, i.e., iodate does not necessarily accumulate in particles. Furthermore, the transformation of particulate iodide to volatile iodine species likely has been overestimated in previous model studies due to negligence of collision-induced upper limits for the reaction rates. However, inorganic reaction cycles still do not seem to be sufficient to reproduce the observed range of iodide – iodate speciation in atmospheric aerosol. Therefore, we also investigate the effects of the recently suggested reaction of HOI with dissolved organic matter to produce iodide. If this reaction is fast enough to compete with the inorganic mechanism, it would not only directly lead to enhanced iodide concentrations but, indirectly via speed-up of the inorganic iodate reduction cycles, also to a decrease in iodate concentrations. Hence, according to our model studies, organic iodine chemistry, combined with inorganic reaction cycles, is able to reproduce observations. The presented chemistry cycles are highly dependent on pH and thus offer an explanation for the large observed variability of the iodide – iodate speciation in atmospheric aerosol.
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Xu, Siqi, Zhouqing Xie, Bing Li, Wei Liu, Liguang Sun, Hui Kang, Hongxia Yang i Pengfei Zhang. "Iodine speciation in marine aerosols along a 15000-km round-trip cruise path from Shanghai, China, to the Arctic Ocean". Environmental Chemistry 7, nr 5 (2010): 406. http://dx.doi.org/10.1071/en10048.
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Environmental context.Iodine in the atmosphere plays an important role in troposphere ozone destruction and climate change. However, cycling of atmospheric iodine is still poorly understood because of uncertainties in iodine speciation in aerosols. Here we report iodine levels and speciation in marine aerosols collected along a cruise path from Shanghai to the Arctic Ocean. Abstract.Total iodine (TI) and water-soluble iodine species in the total suspended particle samples collected onboard a round-trip cruise from Shanghai, China to the Arctic Ocean were measured using inductively coupled plasma mass spectrometry and ion chromatography–inductively coupled plasma mass spectrometry respectively. TI and total soluble iodine (TSI) levels varied considerably both spatially and temporally over the length of the voyage. The maximum iodine levels occurred in the Arctic Ocean in September, whereas the minimum levels occurred in the Western and Northern Pacific Ocean in July. Iodate (IO3 –) was found to be the dominant species in most samples, accounting for 57.8% of TSI on average, whereas iodide and soluble organic iodine only accounted for 16.8% of TSI on average. There was also a significant fraction of insoluble iodine. This finding confirms model predictions of atmospheric iodine speciation, i.e. the predominant iodine species is iodate rather than iodide.
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Sulistyarti, Hermin, Erwin Sulistyo, Sutrisno Sutrisno i Zuri Rismiarti. "Metode Spektrofotometri Secara Tidak Langsung untuk Penentuan Merkuri(II) berdasarkan Pembentukan Kompleks Biru Iodium-Amilum". ALCHEMY Jurnal Penelitian Kimia 15, nr 1 (1.03.2019): 149. http://dx.doi.org/10.20961/alchemy.15.1.15036.149-164.
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<p>Metode spektrofotometri secara tidak langsung telah dikembangkan untuk analisis merkuri(II) berdasarkan perbedaan absorbansi kompleks biru amilum-iodium antara larutan sampel yang mengandung ion merkuri(II) dan larutan blanko yang tidak mengandung ion merkuri(II) dalam sistem pereaksi yang berisi iodida, iodat dan amilum. Pada larutan blanko, semua ion iodida (I<sup>-</sup>) dalam sistem pereaksi dioksidasi oleh iodat menjadi iodium yang dengan adanya amilum membentuk kompleks biru iodium-amilum dan terdeteksi secara spektrofotometri pada 618 nm. Namun, bila sampel mengandung ion merkuri(II), maka sebagian ion iodida akan terikat oleh ion merkuri(II) dan membentuk kompleks tetraiodomerkurat(II), sehingga hanya sisa iodida yang dioksidasi oleh ion iodat menjadi iodium dan membentuk warna biru dengan absorbansi yang lebih rendah dibandingkan absorbansi larutan blanko. Hasil penelitian menunjukkan bahwa perbedaan absorbansi sebanding dengan konsentrasi iodida yang terikat pada ion merkuri(II) sehingga sebanding pula dengan konsentrasi merkuri(II) dalam sampel. Metode yang dikembangkan dioptimasi terhadap beberapa parameter kimia, antara lain konsentrasi larutan iodida, iodat, amilum, dan pH larutan dan pada kondisi optimum memberikan kisaran linier 1 – 9 mg L<sup>-1</sup> ion merkuri(II) dengan R<sup>2</sup> 0,9983, dengan LOD 0,44 mgL<sup>-1</sup>. Metode ini cukup selektif terhadap ion kobalt(II) dan timbal(II), namun ion tembaga(II) dan perak(I) mengganggu pengukuran. Metode ini telah divalidasi menggunakan metode adisi standar yang diaplikasikan ke dalam sampel limbah pertambangan emas dari Lombok dengan hasil yang memuaskan.</p><p><strong>Indirect Spectrophotometry for Mercury(II) Determination Based on The Formation of Blue Starch-Iodine Complex. </strong>Indirect spectrophotometric method for determining mercury(II) concentration has been successfully developed based on the difference of the absorbance of the blue starch-iodine complex in the absence and in the presence of mercury(II). In the absence of mercury(II), all iodide ions (I<sup>-</sup>) in the reagent system are oxidized by iodate to iodine, which in the presence of starch formed a clear blue complex of starch-iodine detected spectrophotometrically at 618 nm. However, if mercury presents in the sample, some of the iodide ions are bound to mercury(II) ion forming tetraiodomercurate(II) complex, and thus, only the remaining of iodide is oxidized by iodate to iodine resulting in lower absorbance of the blue color. The results showed that the delta absorbance was proportional to the concentration of iodide bound to mercury and thus proportional to mercury(II) concentration. To achieve the sensitivity, the method was optimized to the main chemical parameters, such as the concentration of iodide, iodine, iodate, starch, and pH solution. Selectivity of the method was also studied by investigating the effect of interfering ions of copper(II), cobalt (II), lead(II), and silver (I). Under these optimum conditions, the method showed linearity measurements from 1 – 9 mg L<sup>-1</sup> mercury(II) with correlation (R<sup>2</sup>) of 0.996. The method was also successfully applied to determine mercury(II) from small-scale gold mining tailing waste from West Lombok, Indonesia and is prospective for analysis of mercury(II) in mining waste.</p>
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Chikwana, Edward, Bradley Davis, Moshood K. Morakinyo i Reuben H. Simoyi. "Oxyhalogen–sulfur chemistry — Kinetics and mechanism of oxidation of methionine by aqueous iodine and acidified iodate". Canadian Journal of Chemistry 87, nr 6 (czerwiec 2009): 689–97. http://dx.doi.org/10.1139/v09-038.
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The oxidation of methionine (Met) by acidic iodate and aqueous iodine was studied. Though the reaction is a simple two-electron oxidation to give methionine sulfoxide (Met–S=O), the dynamics of the reaction are, however, very complex, characterized by clock reaction characteristics and transient formation of iodine. In excess methionine conditions, the stoichiometry of the reaction was deduced to be IO3– + 3Met → I– + 3Met–S=O. In excess iodate, the iodide product reacts with iodate to give a final product of molecular iodine and a 2:5 stoichiometry: 2IO3– + 5Met + 2H+ → I2 + 5Met–S=O + H2O. The direct reaction of iodine and methionine is slow and mildly autoinhibitory, which explains the transient formation of iodine, even in conditions of excess methionine in which iodine is not a final product. The whole reaction scheme could be simulated by a simple network of 11 reactions.
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Yu, Huan, Lili Ren, Xiangpeng Huang, Mingjie Xie, Jun He i Hang Xiao. "Iodine speciation and size distribution in ambient aerosols at a coastal new particle formation hotspot in China". Atmospheric Chemistry and Physics 19, nr 6 (29.03.2019): 4025–39. http://dx.doi.org/10.5194/acp-19-4025-2019.
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Abstract. Intense new particle formation (NPF) events were observed in the coastal atmosphere during algae growth and farming season at Xiangshan gulf of the east China coast. High nucleation-mode iodine concentrations measured by ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC/Q-TOF-MS) confirmed that the NPF events were induced by iodine species. Our study provides important information on iodine speciation, size distributions, and its role in NPF in the context of heavy air pollution in China's coastal areas. For the first time, we identified 5 inorganic iodine species, 45 organic iodine compounds (35 molecular formulas), and a group of iodide–organic adducts in aerosols. The concentrations and size distributions of iodine species down to 10 nm were measured during the iodine-induced NPF, continental NPF, and non-NPF days at the coastal site and compared to those at an inland site. The iodine in the above four aerosol sample types were characterized by iodate, aromatic iodine compounds, iodoacetic acid or iodopropenoic acid, and iodide–organic adducts, respectively. Iodide and organic iodine compounds were found in the nucleation-mode particles; however, it is still not clear whether they contributed to nucleation or just new particle growth. Wild algae, as well as farmed algae, could be an important NPF source in China's coastal areas.
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Carpenter, Lucy J., Rosie J. Chance, Tomás Sherwen, Thomas J. Adams, Stephen M. Ball, Mat J. Evans, Helmke Hepach i in. "Marine iodine emissions in a changing world". Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences 477, nr 2247 (marzec 2021): 20200824. http://dx.doi.org/10.1098/rspa.2020.0824.
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Iodine is a critical trace element involved in many diverse and important processes in the Earth system. The importance of iodine for human health has been known for over a century, with low iodine in the diet being linked to goitre, cretinism and neonatal death. Research over the last few decades has shown that iodine has significant impacts on tropospheric photochemistry, ultimately impacting climate by reducing the radiative forcing of ozone (O 3 ) and air quality by reducing extreme O 3 concentrations in polluted regions. Iodine is naturally present in the ocean, predominantly as aqueous iodide and iodate. The rapid reaction of sea-surface iodide with O 3 is believed to be the largest single source of gaseous iodine to the atmosphere. Due to increased anthropogenic O 3 , this release of iodine is believed to have increased dramatically over the twentieth century, by as much as a factor of 3. Uncertainties in the marine iodine distribution and global cycle are, however, major constraints in the effective prediction of how the emissions of iodine and its biogeochemical cycle may change in the future or have changed in the past. Here, we present a synthesis of recent results by our team and others which bring a fresh perspective to understanding the global iodine biogeochemical cycle. In particular, we suggest that future climate-induced oceanographic changes could result in a significant change in aqueous iodide concentrations in the surface ocean, with implications for atmospheric air quality and climate.
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&NA;. "Iodine/potassium iodide/povidone iodine". Reactions Weekly &NA;, nr 1283 (styczeń 2010): 58. http://dx.doi.org/10.2165/00128415-201012830-00184.
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Chen, Tong, Wanjing Cui, Ziwei Bi, Yafei Guo, Guoliang Zhu, Xiuyun Pan, Zhiqiang Cui, Zhen Yang i Tianlong Deng. "Trypsin Digestion Pretreatment of Kelp Samples and the Iodine Speciation Analysis of Iodate, Iodide, MIT, and DIT by HPLC-ICP-MS". Journal of Chemistry 2023 (18.07.2023): 1–9. http://dx.doi.org/10.1155/2023/5072070.
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The analysis of iodine content in kelp is mainly focused on determining total iodine content, which lacks a rapid and sensitive analytical method for iodine species corresponding to iodate, iodide, monoiodotyrosine (MIT), and diiodo-tyrosine (DIT). Based on exploring the pretreatment methods of enzymatic hydrolysis of kelp, a rapid determination method of high-performance liquid chromatography and inductively coupled plasma mass spectrometry (HPLC-ICP-MS) for different iodine species existed in kelp samples was established. The pretreatment method is trypsin hydrolysis of kelp samples treated at 50°C for 10 hours, then the extraction solution was obtained by centrifugation, and filtration was proved for the first time. A high-efficiency separation anion-exchange column (Dionex IonPac AS-14) for iodate, iodide, MIT, and DIT with 0.1 mol·L−1(NH4)2CO3 solution at pH = 9 as a mobile phase, a flow rate of 0.8 mL·min−1 for the first 1500 s, and 1.2 mL·min−1 for the last 1800 s was confirmed. The linear ranges of the standard calibrations on four iodine species are 1.0–150 μg·L−1, and the detection limits are 1.62, 1.02, 1.59, and 2.55 μg·L−1, respectively, while the RSD values of four iodine species are all less than 2%. Under the optimized conditions, the proposed method was successfully applied for the speciation analysis of iodine in kelp samples.
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Evglevskiy, A. A., O. M. Shvets i T. I. Mikhaleva. "Clinical and metabolic effects of the original iodine metabolic composition in the experiment on calves". E3S Web of Conferences 285 (2021): 04003. http://dx.doi.org/10.1051/e3sconf/202128504003.
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The article provides a theoretical justification for the development of a complex iodine metabolic composition based on an iodinepolymer complex (iodinol) and succinic acid. The research on the effectiveness of the proposed composition for the correction of energymetabolic disorders in calves with severe iodine deficiency was carried out. The objects of research were calves with clinical signs of iodine deficiency and pronounced energy metabolic disorders. During the experiment, it was found that the test calves showed a marked improvement in the clinical condition. The thyroid status normalized, the total protein and glucose indicators approached the physiological norm, and the reserve alkalinity of the blood increased. The energetic metabolic effect was due to the combined action of iodinol and succinic acid. The obtained results indicate the opening prospect of an injection method for the use of an iodine polymer complex based on iodine-iodide with polyvinyl alcohol (iodinol) in combination with sodium succinate, not only as an effective approach to cupping and eliminating the iodine deficiency symptoms, but also as an active energy-metabolic drug with a potentially high anti-infective activity.
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Afanasiev, D. E., O. V. Kaminskyi, T. K. Loganovska, O. V. Kopylova, I. G. Chikalova, I. M. Muraviova i N. S. Dombrovska. "PROBLEMATIC ASPECTS, COMPLICATIONS, MISCONCEPTIONS AND DEBATABLE ISSUES OF IODINE PROPHYLAXIS IN RADIATION EVENTS (REVIEW)". Проблеми радіаційної медицини та радіобіології = Problems of Radiation Medicine and Radiobiology 27 (2022): 25–59. http://dx.doi.org/10.33145/2304-8336-2022-27-25-59.
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Prerequisite. Since the advent of nuclear energy, industry and weapons, a possibility of radiation events i.e. incidents and accidents had emerged. Given the presence of radioactive iodine as part of environmental contamination, the response of authorities and medical services consists, in particular, in carrying out the emergency iodine prophylaxis among specialists and general population. And along with the fact that emergency iodine prophylaxis is a generally accepted measure in radiation events accompanied by the release of radioactive iodine, some methods of its implementation were and remain in certain sources and instructions/recommendations contradictory and even false. Such inconsistency increases the potential risks of health effects of radioactive iodine and exacerbates the sense of fear and uncertainty among the population involved in the incident. Objective: to consider and review the essence of emergency iodine prophylaxis during radiation events, physiological aspects of iodine metabolism in the body, properties of individual iodine prophylaxis agents that are recommended, and to justify the rationality of using some of them along with absurdity/inadmissibility of others; substantiate the creation of a unified preventive information strategy regarding the event in order to reduce anxiety and other negative psychological consequences among the affected population. Materials and methods. The review was performed by searching the abstract and scientometric databases and printed publications. Results. In the event of serious radiation events at nuclear power plants and industry facilities, radioactive iodine is highly likely to enter the environment. With the threat of radioactive iodine incorporation or with its incorporation that has already begun, it is absolutely necessary to carry out the emergency iodine prophylaxis. Such prevention should be carried out with stable iodine preparations such as potassium iodide or potassium iodate in special pharmaceutical formulas. Dosing of drugs in age and population groups should be carried out by specialists in radiation medicine and radiation safety in accordance with internationally recognized guidelines. The use of iodinecontaining food additives, iodine solution for external use and Lugol’s solution is categorically unacceptable due to complete ineffectiveness, impracticality of implementation, and sometimes due to the threat of serious harm to health. Conclusions. Clear preparedness plans for possible radiation accidents and incidents, as well as successfully implemented appropriate preventive measures, including emergency iodine prophylaxis, are crucial for the effective and successful response to such events. Emergency iodine prophylaxis during radiation events should be carried out exclusively under the guidance of specialists in radiation medicine and radiation safety using special pharmaceutical formulas of potassium iodide or potassium iodate in doses recognized by the international scientific community. Other means of emergency iodine prophylaxis, including «handicraft»/home preparations, are absolutely unacceptable. Implementation of this protective measure should be accompanied by a coordinated information campaign in order to minimize purely radiation risks and to preserve the psychological well-being of the population. Key words: radiation events, radiation accident, radiation incident, nuclear industry, nuclear power, radioactive iodine, exposure, emergency iodine prophylaxis, stable iodine, potassium iodide, potassium iodate, psychological well-being of population.
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Swamy, Nagaraju, Kudige Nagaraj Prashanth i Kanakapura Basavaiah. "Titrimetric and spectrophotometric assay of diethylcarbamazine citrate in formulations using iodate and iodide mixture as reagents". Brazilian Journal of Pharmaceutical Sciences 51, nr 1 (marzec 2015): 43–52. http://dx.doi.org/10.1590/s1984-82502015000100005.
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One titrimetric and two spectrophotometric methods are proposed for the determination of diethylcarbamazine citrate (DEC) in bulk drug and in formulations using potassium iodate and potassium iodide as reagent. The methods employ the well-known analytical reaction between iodate and iodide in the presence of acid. In titrimetry (method A), the drug was treated with a measured excess of thiosulfate in the presence of unmeasured excess of iodate-iodide mixture and after a standing time of 10 min, the surplus thiosulfate was determined by back titration with iodine towards starch end point. Titrimetric assay is based on a 1:3 reaction stoichiometry between DEC and iodine and the method is applicable over 2.0-10.0 mg range. The liberated iodine is measured spectrophotometrically at 370 nm (method B) or the iodine-starch complex measured at 570 nm (method C). In both methods, the absorbance is found to be linearly dependent on the concentration of iodine, which in turn is related to DEC concentration. The calibration curves are linear over 2.5-50 and 2.5-30 µg mL-1 DEC for method B and method C, respectively. The calculated molar absorptivity and Sandell sensitivity values were 6.48×103 L mol-1 cm-1 and 0.0604 µg cm-2, respectively, for method B, and their respective values for method C are 9.96×103 L mol-1 cm-1 and 0.0393 µg cm-2. The intra-day and inter-day accuracy and precision studies were carried out according to the ICH guidelines. The methods were successfully applied to the analysis of DEC formulations.
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Guido-Garcia, Fabiola, Gareth T. W. Law, Jonathan R. Lloyd, Paul Lythgoe i Katherine Morris. "Bioreduction of iodate in sediment microcosms". Mineralogical Magazine 79, nr 6 (listopad 2015): 1343–51. http://dx.doi.org/10.1180/minmag.2015.079.6.10.
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AbstractIodine-129 is a high-yield fission product formed in nuclear reactors and is a risk-driving radionuclide in both contaminated land and radioactive waste disposal due to its high mobility and long half-life. Here, the bioreduction behaviour of iodate was investigated by tracking iodine speciation and concentration in solution during the development of progressive anoxia in sediment microcosm experiments incubated at neutral pH. Experiments with acetate added as an electron donor showed the expected cascade of terminal electron-accepting processes. Analysis of solution chemistry showed reduction of iodate to iodide during the early stages of metal (Mn(IV) and Fe(III)) reduction, but with no significant retention of iodine species on solids. There was, however, a net release of natural iodine associated with the sediments to solution when robust iron reduction / sulfate reduction had developed. In addition, over 210 days, the controls with no electron donor and the sterile controls showed no Mn(IV) or Fe(III) reduction but displayed modest sorption of iodate to the sediments in the absence of bioreduction. Overall these results show that under oxic conditions iodate may be partially sorbed to sediments over extended periods but that development of mildly reducing conditions leads to the reductive release of iodine to solution as iodide.
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Evglevskiy, Alexei, Olga Shvets i Tatyana Mikhaleva. "Correction of energometabolic disorders atsignificant iodine deficiency in calves". BIO Web of Conferences 37 (2021): 00019. http://dx.doi.org/10.1051/bioconf/20213700019.
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The paper is devoted to the development and use of theiodomethaboliccomplex based on iodine-iodide with polyvinyl alcohol (iodinol) and succinic acid.It was found that the inclusion of succinic acid or sodium succinate in a similar concentration in the composition of iodinol allowed not only qualitatively improving the pharmacological properties of iodinol, but also obtaining an energometabolic composition suitable for parenteral administration.The results of using the iodomethabolic compositionrevealed that with the parenteral administration to calves with clinically pronounced iodine deficiency, it provides effective normalization of pathological biochemical processes in the body of calves (metabolic effect) and pronounced activation of energy metabolism (energy effect), and in general, an energometabolic effect that ensures clinical recovery of animals from iodine deficiency.
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Тrohimenko, O., O. Zaporozhets i A. Тrohimenko. "IODIMETRY-PHOTOMETRIC DETERMINATION OF PERIODATE, IODATE AND BROMATE IN WATER SOLUTIONS". Bulletin of Taras Shevchenko National University of Kyiv. Chemistry, nr 2(54) (2018): 56–59. http://dx.doi.org/10.17721/1728-2209.2017.2(54).10.
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A simple and accurate three-step procedure for sequential spectrophotometric determinations of periodate, iodate and bromate in aqueous media has been developed. At the first stage the determination of periodate is based on the selective oxidation of the excess amount of iodide at pH=4.8 to produce iodine (triiodide), that can be found by spectrophotometric detection (λmax=350 nm). After detecting the analytical signal, iodine is removed from the solution by sorption on the polyurethane foam. In the second stage the determination of iodate is based on the selective oxidation of iodide at pH=3.0 to produce iodine (triiodide), that also can be found by spectrophotometric detection (λmax=350 nm). After detecting the analytical signal, also iodine is removed from the solution by sorption on the polyurethane foam. In the third stage the determination of bromate is based on the selective oxidation of iodide at pH=1.0 to produce iodine (triiodide), that also can be found by spectrophotometric detection (λmax=350 nm). It has been established that the equilibrium in the reaction (ІО4– + 7І– + 8Н+ → 4І2 +4Н2О) is established in 3 minutes at pH=4.8. The equilibrium in the both reactions (ІО3– + 5І– + 6Н+ → 3І2 +3Н2О and BrО3– + 6І– + 6Н+ → 3І2 +Br– +3Н2О) is established in 7 minutes at pH=3.0 and at pH=1.0 respectively. It was found that oxohalogates are quantitatively converted to I2 with ~ 100-fold molar excess iodide at appropriate optimal pH values. Schematically, the determination of IO4–, IO3– and BrO3– in their combined presence can be represented as follows: where SF is spectrophotometry in a solution at 350 nm: PUF is the polyurethane foam. Based on the data obtained, the model mixtures of periodate, iodate and bromate by sequential iodiometry-photometric method were analyzed. The error of determination in mixtures of each oxo-halogenate did not exceed 5%.
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Butler, ECV, i JD Smith. "Iodine and arsenic redox species in oxygen-deficient estuarine waters". Marine and Freshwater Research 36, nr 3 (1985): 301. http://dx.doi.org/10.1071/mf9850301.
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The distribution of the redox species of iodine and arsenic in two isolated pools of seawater underlying river water in deep holes in the estuary of the Yarra River is described. In the river water, the dominant species are iodide and As(V). In the saline water of these holes, there are levels of iodine and arsenic greater than are present in the original seawater. The subhalocline waters contained <0.22 ml 1-1 of dissolved oxygen, and the redox poise was intermediate between oxic and anoxic conditions. Most of the iodate originally in the seawater was reduced to iodide, but As111) and As(V) coexisted. Iodine and arsenic appear to have entered the water from the anoxic sediment.
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Mamenko, M. E. "Iodine Deficiency in the World and in Ukraine: Current State of the Problem". Modern pediatrics. Ukraine, nr 7(111) (29.11.2020): 40–46. http://dx.doi.org/10.15574/sp.2020.111.40.
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Today, efforts of governments and communities are aimed at coping with severe impacts of new viral disease outbreaks caused by SARS-Cov-2. However, there are gaps in care for patients with many chronic diseases, and programs to prevent the most common conditions are being prevented or stopped. This applies to diseases directly related to eating disorders. To solve the problem at the population level, it is critically necessary to adopt legislative acts regulating the universal iodization of table salt in the country. Currently, in Ukraine, potassium iodate is used for salt enrichment, which is a more stable compound than iodide that was used earlier. Potassium iodate allows you to store iodized salt for a year or more, does not change the taste and smell of food, and can be used for preserving and storing food. For the most vulnerable categories of the population (newborns, children, pregnant women and mothers who are breastfeeding), the use of iodine supplements remains relevant. The optimal tool for such preventive interventions is supplements containing the physiological dose of iodine. On the Ukrainian market, they are presented in the form of pills of potassium iodide with a content of 100 mcg and 200 mcg of iodine. The common goal should be Ukraine without iodine deficiency, where each person receives the amount of iodine corresponding to their needs, and children are provided with the opportunity for adequate intellectual development. No conflict of interest was declared by the authors. Key words: children, pregnant women, iodine deficiency, iodine supplements.
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Ibragim, Umbarov, Khaid Turayev, Nuriddin Uralov, Sayyod Abduraxmonov, Chori Musayev, Khurshid Tursunov, Khasan Eshonqulov i Nargiza Kadirova. "Investigating the processes and rate of iodide ion and compound oxidation in subterranean hydrothermal waters". BIO Web of Conferences 105 (2024): 05019. http://dx.doi.org/10.1051/bioconf/202410505019.
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Studies using physico-chemical methods have been conducted to evaluate the oxidative characteristics of various reagents for the technological extraction of iodine from groundwater and sufficient data have been obtained. According to the research results, iodine is predominantly present in the form of molecular iodine (85.6%), iodide ions (3.2%), iodate (9.1%) and iodine chloride (2.1%) were detected. Preserving all forms of iodine in solution at the same time is possible only in an alkaline environment, where the oxidizing properties of iodates are sharply reduced. This information is important for choosing a method for purifying iodine paste using various physical and chemical methods. From experiments in research, the beginning of the release of elemental iodine was noted at a voltage above 0.250 V and a pH of 5-3 or less. In this case, the solution usually becomes dark red with a reddish or brownish tint, which indicates the formation of complex compounds of iodine with other ions in the solution.
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Paquette, Jean, i Beverly L. Ford. "Iodine chemistry in the +1 oxidation state. I. The electronic spectra of OI−, HOI, and H2OI+". Canadian Journal of Chemistry 63, nr 9 (1.09.1985): 2444–48. http://dx.doi.org/10.1139/v85-404.
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Electronic spectra are reported for the hypoiodite ion (OI−), hypoiodous acid (HOI), and its conjugate acid (H2OI+) in aqueous media. Iodine in the +1 oxidation state was produced by either of the two rapid reactions[Formula: see text]or[Formula: see text]Spectroscopic evidence of the disproportionation of OI−/HOI/H2OI+ to iodide and iodate in basic media, and to iodine and iodate in acid media, was obtained. The results are consistent with previously reported values for the pKa of HOI and H2OI+.
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Shim, Ha, Jung Yang, Sun-Wook Jeong, Chang Lee, Lee Song, Sajid Mushtaq, Dae Choi, Yong Choi i Jongho Jeon. "Silver Nanomaterial-Immobilized Desalination Systems for Efficient Removal of Radioactive Iodine Species in Water". Nanomaterials 8, nr 9 (26.08.2018): 660. http://dx.doi.org/10.3390/nano8090660.
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Increasing concerns regarding the adverse effects of radioactive iodine waste have inspired the development of a highly efficient and sustainable desalination process for the treatment of radioactive iodine-contaminated water. Because of the high affinity of silver towards iodine species, silver nanoparticles immobilized on a cellulose acetate membrane (Ag-CAM) and biogenic silver nanoparticles containing the radiation-resistant bacterium Deinococcus radiodurans (Ag-DR) were developed and investigated for desalination performance in removing radioactive iodines from water. A simple filtration of radioactive iodine using Ag-CAM under continuous in-flow conditions (approximately 1.5 mL/s) provided an excellent removal efficiency (>99%) as well as iodide anion-selectivity. In the bioremediation study, the radioactive iodine was rapidly captured by Ag-DR in the presence of high concentration of competing anions in a short time. The results from both procedures can be visualized by using single-photon emission computed tomography (SPECT) scanning. This work presents a promising desalination method for the removal of radioactive iodine and a practical application model for remediating radioelement-contaminated waters.
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Saller, Bernhard, Rudolf Hoermann, Michael M. Ritter, Roland Morell, Torsten Kreisig i Klaus Mann. "Course of thyroid iodine concentration during treatment of endemic goitre with iodine and a combination of iodine and levothyroxine". Acta Endocrinologica 125, nr 6 (grudzień 1991): 662–67. http://dx.doi.org/10.1530/acta.0.1250662.
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Abstract. In the treatment of endemic goitre, the concept of giving levothyroxine in combination with iodine offers a promising therapeutic approach by influencing not only TSH secretion but also intrathyroidal iodine content. However, little is known about the doses of iodine necessary to correct intrathyroidal iodine deficiency. To get more information on this important issue, we conducted a prospective, double-blind study on the effect of a monotherapy with 500 μg iodide/day and a combined treatment with 100 μg levothyroxine and 100 μg iodide/day on thyroid iodine concentration as measured by fluorescence scintigraphy. In a group of 12 patients, a 4-month treatment with 100 μg levothyroxine and 100 μg iodide/day did not significantly affect thyroid iodine concentration (0.35±0.14 vs 0.37±0.11 mg/g). The application of 500 μg iodide/day in these patients during a second 4-month period resulted in a sharp increase in thyroid iodine concentration from 0.37±0.11 to 0.61±0.14 mg/g (p<0.01). Another group of 8 patients first treated with 500 μg iodide/day also showed a significant increase in iodine concentration from 0.35±0.14 to 0.65±0.20 mg/g (p<0.01). After switching to the combination regimen during a second 4-month period, thyroid iodine concentration slightly decreased, particularly in those patients with high iodine concentrations after monotherapy with iodide (0.65±0.20 vs 0.50±0.12 mg/g, p<0.05). In conclusion, treatment with 500 μg iodide/day could sharply increase thyroid iodine concentration in patients with endemic goitre. In contrast, a combination of 100 μg levothyroxine and 100 μg iodide/day had no significant effect on thyroid iodine concentration.
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Zhang, L. Y., X. L. Hou i S. Xu. "Speciation of <sup>127</sup>I and <sup>129</sup>I in atmospheric aerosols at Risø, Denmark: insight into sources of iodine isotopes and their species transformations". Atmospheric Chemistry and Physics Discussions 15, nr 17 (15.09.2015): 25139–73. http://dx.doi.org/10.5194/acpd-15-25139-2015.
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Abstract. Speciation analysis of iodine in aerosols is a very useful approach for understanding geochemical cycling of iodine in the atmosphere. In this study, overall iodine species, including water-soluble iodine species (iodide, iodate and water-soluble organic iodine), NaOH-soluble iodine and insoluble iodine have been determined for 129I and 127I in the aerosols collected at Risø, Denmark, between March and May 2011 (shortly after the Fukushima nuclear accident) and in December 2014. The measured concentrations of total iodine are in the range of 1.04–2.48 ng m−3 for 127I and (11.3–97.0) × 105 atoms m−3 for 129I, and 129I / 127I atomic ratios of (17.8–86.8) × 10−8. The contribution of Fukushima-derived 129I (peak value of 6.3 × 104 atoms m−3) is estimated to be negligible (less than 6 %) compared to the total 129I concentration in northern Europe. The concentrations and species of 129I and 127I in the aerosols are found to be strongly related to their sources and atmospheric pathways. Aerosols that were transported over the contaminated ocean, contained higher amounts of 129I than aerosols transported over the European continent. The high 129I concentrations of the marine aerosols are attributed to secondary emission from heavily 129I-contaminated seawater rather than primary gaseous release from nuclear reprocessing plants. Water-soluble iodine was found to be a minor fraction to total iodine for both 127I (7.8–13.7 %) and 129I (6.5–14.1 %) in ocean-derived aerosols, but accounted for 20.2–30.3 % for 127I and 25.6–29.5 % for 129I in land-derived aerosols. Iodide was the predominant form of water-soluble iodine, accounting for more than 97 % of the water-soluble iodine. NaOH-soluble iodine seems to be independent of the sources of aerosols. The significant proportion of 129I and 127I found in NaOH-soluble fractions is likely bound with organic substances. In contrast to water-soluble iodine however, the sources of air masses exerted distinct influences on insoluble iodine for both 129I and 127I, with higher values for marine air masses and lower values for terrestrial air masses.
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Li, Jiaqi, Mengzhou Wang, Xu Zhao, Zitong Li, Yihui Niu, Sufeng Wang i Qina Sun. "Efficient Iodine Removal by Porous Biochar-Confined Nano-Cu2O/Cu0: Rapid and Selective Adsorption of Iodide and Iodate Ions". Nanomaterials 13, nr 3 (31.01.2023): 576. http://dx.doi.org/10.3390/nano13030576.
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Iodine is a nuclide of crucial concern in radioactive waste management. Nanomaterials selectively adsorb iodine from water; however, the efficient application of nanomaterials in engineering still needs to be developed for radioactive wastewater deiodination. Artemia egg shells possess large surface groups and connecting pores, providing a new biomaterial to remove contaminants. Based on the Artemia egg shell-derived biochar (AES biochar) and in situ precipitation and reduction of cuprous, we synthesized a novel nanocomposite, namely porous biochar-confined nano-Cu2O/Cu0 (C-Cu). The characterization of C-Cu confirmed that the nano-Cu2O/Cu0 was dispersed in the pores of AES biochar, serving in the efficient and selective adsorption of iodide and iodate ions from water. The iodide ion removal by C-Cu when equilibrated for 40 min exhibited high removal efficiency over the wide pH range of 4 to 10. Remarkable selectivity towards both iodide and iodate ions of C-Cu was permitted against competing anions (Cl−/NO3−/SO42−) at high concentrations. The applicability of C-Cu was demonstrated by a packed column test with treated effluents of 1279 BV. The rapid and selective removal of iodide and iodate ions from water is attributed to nanoparticles confined on the AES biochar and pore-facilitated mass transfer. Combining the advantages of the porous biochar and nano-Cu2O/Cu0, the use of C-Cu offers a promising method of iodine removal from water in engineering applications.
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Zompanti, Alessandro, Simone Grasso, Anna Sabatini, Luca Vollero, Giorgio Pennazza i Marco Santonico. "A Multi-Sensor System for Sea Water Iodide Monitoring and Seafood Quality Assurance: Proof-of-Concept Study". Sensors 21, nr 13 (29.06.2021): 4464. http://dx.doi.org/10.3390/s21134464.
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Iodine is a trace chemical element fundamental for a healthy human organism. Iodine deficiency affects about 2 billion people worldwide causing from mild to severe neurological impairment, especially in children. Nevertheless, an adequate nutritional intake is considered the best approach to prevent such disorders. Iodine is present in seawater and seafood, and its common forms in the diet are iodide and iodate; most iodide in seawater is caused by the biological reduction of the thermodynamically stable iodate species. On this basis, a multisensor instrument which is able to perform a multidimensional assessment, evaluating iodide content in seawater and seafood (via an electrochemical sensor) and discriminating when the seafood is fresh or defrosted quality (via a Quartz Micro balance (QMB)-based volatile and gas sensor), is strategic for seafood quality assurance. Moreover, an electronic interface has been opportunely designed and simulated for a low-power portable release of the device, which should be able to identify seafood over or under an iodide threshold previously selected. The electrochemical sensor has been successfully calibrated in the range 10–640 μg/L, obtaining a root mean square error in cross validation (RMSECV) of only 1.6 μg/L. Fresh and defrosted samples of cod, sea bream and blue whiting fish have been correctly discriminated. This proof-of-concept work has demonstrated the feasibility of the proposed application which must be replicated in a real scenario.
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Gardas, A., i H. Domek. "Iodine induced alteration in immunological and biochemical properties of thyroglobulin." Acta Biochimica Polonica 40, nr 2 (30.06.1993): 237–40. http://dx.doi.org/10.18388/abp.1993_4824.
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The influence of iodine-iodide solution on the biochemical and immunological properties of human thyroglobulin (hTg) were studied. Human Tg preincubated with the iodine-iodide solution is split to small molecular mass fragments after disulphide bridge reduction with dithiothreitol. The peptide bond cleavage by iodine pretreatment and reduction is possibly linked with the coupling reaction of diiodotyrosyl residues. Pretreatment of hTg with iodine-iodide solution at 1-10 microM decreased the binding of autoantibodies to hTg. The iodine-iodide induced inactivation of hTg autoepitopes is pH dependent and is possibly caused by iodination of tyrosyl residues present in the epitope structure.
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&NA;. "Potassium iodide/iodine". Reactions Weekly &NA;, nr 1383 (styczeń 2012): 31. http://dx.doi.org/10.2165/00128415-201213830-00109.
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&NA;. "Potassium iodide/iodine". Reactions Weekly &NA;, nr 1236 (styczeń 2009): 29. http://dx.doi.org/10.2165/00128415-200912360-00081.
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&NA;. "Potassium iodide/iodine". Reactions Weekly &NA;, nr 1306 (czerwiec 2010): 31. http://dx.doi.org/10.2165/00128415-201013060-00108.
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Glowa, G. A., i J. C. Wren. "Aqueous-gas phase partitioning and hydrolysis of organic iodides". Canadian Journal of Chemistry 81, nr 3 (1.03.2003): 230–43. http://dx.doi.org/10.1139/v03-024.
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The volatility and decomposition of organic iodides in a reactor containment building are important parameters to consider when assessing the potential consequences of a nuclear reactor accident. However, there are few experimental data available for the volatilities (often reported as partition coefficients) or few rate constants regarding the decomposition (via hydrolysis) of organic iodides. The partition coefficients and hydrolysis rate constants of eight organic iodides, having a range of molecular structures, have been measured in the current studies. This data, and data accumulated in the literature, have been reviewed and discussed to provide guidelines for appropriate organization of organic iodides for the purpose of modelling iodine behaviour under postulated nuclear reactor accident conditions. After assessment of the partition coefficients and their temperature dependences of many classes of organic compounds, it was found that organic iodides could be divided into two categories based upon their volatility relative to molecular iodine. Similarly, hydrolysis rates and their temperature dependences are assigned to the two categories of organic iodides.Key words: organic iodide, hydrolysis, partition coefficient, iodine behaviour model, nuclear reactor safety.
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Zhang, Luyuan, Xiaolin Hou i Sheng Xu. "Speciation of <sup>127</sup>I and <sup>129</sup>I in atmospheric aerosols at Risø, Denmark: insight into sources of iodine isotopes and their species transformations". Atmospheric Chemistry and Physics 16, nr 4 (23.02.2016): 1971–85. http://dx.doi.org/10.5194/acp-16-1971-2016.
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Abstract. Speciation analysis of iodine in aerosols is a very useful approach for understanding geochemical cycling of iodine in the atmosphere. In this study, overall iodine species, including water-soluble iodine species (iodide, iodate and water-soluble organic iodine), NaOH-soluble iodine, and insoluble iodine have been determined for 129I and 127I in the aerosols collected at Risø, Denmark, during March and May 2011 (shortly after the Fukushima nuclear accident) and in December 2014. The measured concentrations of total iodine are in the range of 1.04–2.48 ng m−3 for 127I and (11.3–97.0) × 105 atoms m−3 for 129I, corresponding to 129I ∕ 127I atomic ratios of (17.8–86.8) × 10−8. The contribution of Fukushima-derived 129I (peak value of 6.3 × 104 atoms m−3) is estimated to be negligible (less than 6 %) compared to the total 129I concentration in northern Europe. The concentrations and species of 129I and 127I in the aerosols are found to be strongly related to their sources and atmospheric pathways. Aerosols that were transported over the contaminated seas contained higher concentrations of 129I than aerosols transported over the European continent. The high 129I concentrations of the marine aerosols are attributed to secondary emission of marine discharged 129I in the contaminated seawater in the North Sea, North Atlantic Ocean, English Channel, Kattegat, etc., rather than direct gaseous release from the European nuclear reprocessing plants (NRPs). Water-soluble iodine was found to be a minor fraction to the total iodine for both 127I (7.8–13.7 %) and 129I (6.5–14.1 %) in ocean-derived aerosols, but accounted for 20.2–30.3 % for 127I and 25.6–29.5 % for 129I in land-derived aerosols. Iodide was the predominant form of water-soluble iodine, accounting for more than 97 % of the water-soluble iodine. NaOH-soluble iodine seems to be independent of the sources of aerosols. The significant proportion of 129I and 127I found in NaOH-soluble fractions is likely bound with organic substances. In contrast to water-soluble iodine, the sources of air masses exerted distinct influences on insoluble iodine for both 129I and 127I, with higher values for marine air masses and lower values for terrestrial air masses.
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Zeghal, Najiba, François Gondran, Mebarka Redjem, Marie-Dominique Giudicelli, Youssef Aissouni i Emile Vigouroux. "Iodide and T4 kinetics in plasma, thyroid gland and skin of 10-day-old rats: effects of iodine deficiency". Acta Endocrinologica 127, nr 5 (listopad 1992): 425–34. http://dx.doi.org/10.1530/acta.0.1270425.
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The effects of iodine deficiency on the peripheral metabolism of thyroid hormone in immature rat were evaluated by measuring the kinetics of iodide and thyroxine (T4) in control and iodine-deficient 10-day-old rats. Iodine-deficient pups were obtained by giving the mother drinking water containing perchlorate; this anion is not transferred but prevents iodine transfer in the mother's milk. Labelled iodocompounds were measured in plasma, thyroid and skin for 48 h following intravenous injection of Na131I plus [125I]T4. Data were interpreted by compartmental analysis. The iodide plasma clearance rate, plasma equivalent distribution volume, plasma concentration, production and iodine thyroid content of iodine-deficient rats were significantly lower (−29%, −31%, −84%, −89% and −87% respectively) than in control 10-day-old rats. The iodide thyroid uptake was reduced (−47%) but remained higher than the release of iodine as T4. Cutaneous iodine was lost much more quickly by iodine-deficient pups than by control pups, explaining the decreased iodide distribution volume. The parameters of T4 metabolism were not changed by iodine deficiency, except for a slight but significant reduction of the thyroxinemia and T4 pools (−13%). Thence, T4 production was not significantly changed (about 8 pmol/h in control and iodine-deficient rats). The labelled T4 curves in iodine-deficient and control skin were superimposed and the patterns of labelled T3 derived from [125I]T4 were identical. Thus, the skin of immature rats converts T4 to T3; this process was not disturbed by iodine deficiency. The thyroid function of immature rats is particularly resistant to iodine deficiency, but the mechanisms remain unknown.
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Mohiuddin, Muhammad, Zahid Hussain, Asim Abbasi, Jawad Ali, Muhammad Irshad, Muhammad Atiq Ur Rehman Tariq, Anum Intisar, Aiman Hina, Qamar Uz Zaman i Anne Wai Man Ng. "Sawdust Amendment in Agricultural and Pasture Soils Can Reduce Iodine Losses". Sustainability 14, nr 20 (20.10.2022): 13620. http://dx.doi.org/10.3390/su142013620.
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Iodine loss is common in the soil of hilly regions due to higher precipitation rates and steeper slopes. Iodine deficiency in soil reduces iodine’s bioavailability to fruits and vegetables and consequently may contribute to health complications. However, the iodine retention of soils after the addition of selected organic and inorganic amendments has not been studied. Therefore, a study was carried out to investigate iodine loss during surface runoff. For this purpose, a soil amendment (namely, sawdust, charcoal, wood ash, lime or gypsum) was applied separately to pasture and agricultural soils under natural rainfall conditions. The soil was fertigated with iodine in the form of potassium iodide (KI) at the rate of 200 ppm. Surface runoff was related to soil properties. Results showed that iodine content in surface runoff was linearly related with soil pH (R2 = 0.89, p < 0.05) and inversely related with soil organic carbon (R2 = −0.76, p < 0.05). Soils amended with sawdust had significantly reduced iodine content in runoff. A higher amount of iodine was lost via surface runoff from soil after inorganic amendment. Soil amendments were varied for iodine retention in soil in the order of sawdust > charcoal > wood ash > lime > gypsum. The study results indicated that organic amendments, especially sawdust, improved soil properties and increased the iodine retention capacity of soils.
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Zaremba, Agata, Katarzyna Waszkowiak, Dominik Kmiecik, Anna Jędrusek-Golińska, Maciej Jarzębski i Krystyna Szymandera-Buszka. "The Selection of the Optimal Impregnation Conditions of Vegetable Matrices with Iodine". Molecules 27, nr 10 (23.05.2022): 3351. http://dx.doi.org/10.3390/molecules27103351.
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This study aimed to determine the use of selected vegetables (pumpkin, cauliflower, broccoli, carrot) as carriers of potassium iodide (KI) and potassium iodate (KIO3) by determining changes in iodine content under various conditions of impregnation as the degree of hydration, impregnated sample temperature, and impregnation time. The influence of these conditions on iodine contents in vegetables after their fortification and storage (21 °C/230 days) was analyzed. The results showed that all selected vegetables could be efficient iodine carriers. However, the conditions of the impregnation process are crucial for fortification efficiency, particularly the degree of hydration and the temperature of the impregnated samples before drying. The results showed that the lowest iodine content was in samples fortified at 4 °C and 1:4 hydration. On the other hand, the highest reproducibility of iodine was for the following fortification conditions: temperature of −76 °C and hydration of 1:1. The studies confirmed the higher stability of iodine in KIO3 form compared to KI. To increase recovery of the introduced iodine in the product after drying, using the conditioning step at 4 °C is not recommended. We recommend freezing vegetables immediately after the impregnation process
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Zaremba, Agata, Marzanna Hęś, Anna Jędrusek-Golińska, Monika Przeor i Krystyna Szymandera-Buszka. "The Antioxidant Properties of Selected Varieties of Pumpkin Fortified with Iodine in the Form of Potassium Iodide and Potassium Iodate". Foods 12, nr 14 (23.07.2023): 2792. http://dx.doi.org/10.3390/foods12142792.
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This study aimed to investigate the use of selected pumpkin varieties as carriers of potassium iodide (KI) and potassium iodate (KIO3) at different concentrations (2.3, 0.23, and 0.023 mg/100 g). It was hypothesized that the concentrations and form of iodine fortification in pumpkins affect the antioxidant activity of pumpkins. The results showed a high recovery of the introduced iodine in all pumpkin varieties after drying, as well as high iodine stability during storage, especially for KIO3. However, statistical analysis confirmed a relationship between the forms and concentration of iodine and the ABTS cation radical and the DPPH radical test results. In the systems with iodine concentration at 0.023 and 0.23 mg/100 g, the antioxidant activity did not change. However, for all pumpkin varieties fortified with a KIO3 concentration at 3.9 mg/100 g (2.3 mg/100 g of iodine), a statistically significant decrease in free-radical scavenging was confirmed. Therefore, for maximum effectiveness in pumpkin’s free-radical scavenging indices, it is suggested to introduce iodine in the form of KI and KIO3, but in controlled concentrations. However, KIO3 should be added at a maximum amount of 0.39 mg/100 g.
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Legrand, Michel, Joseph R. McConnell, Susanne Preunkert, Monica Arienzo, Nathan Chellman, Kelly Gleason, Tomás Sherwen, Mat J. Evans i Lucy J. Carpenter. "Alpine ice evidence of a three-fold increase in atmospheric iodine deposition since 1950 in Europe due to increasing oceanic emissions". Proceedings of the National Academy of Sciences 115, nr 48 (12.11.2018): 12136–41. http://dx.doi.org/10.1073/pnas.1809867115.
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Iodine is an important nutrient and a significant sink of tropospheric ozone, a climate-forcing gas and air pollutant. Ozone interacts with seawater iodide, leading to volatile inorganic iodine release that likely represents the largest source of atmospheric iodine. Increasing ozone concentrations since the preindustrial period imply that iodine chemistry and its associated ozone destruction is now substantially more active. However, the lack of historical observations of ozone and iodine means that such estimates rely primarily on model calculations. Here we use seasonally resolved records from an Alpine ice core to investigate 20th century changes in atmospheric iodine. After carefully considering possible postdepositional changes in the ice core record, we conclude that iodine deposition over the Alps increased by at least a factor of 3 from 1950 to the 1990s in the summer months, with smaller increases during the winter months. We reproduce these general trends using a chemical transport model and show that they are due to increased oceanic iodine emissions, coupled to a change in iodine speciation over Europe from enhanced nitrogen oxide emissions. The model underestimates the increase in iodine deposition by a factor of 2, however, which may be due to an underestimate in the 20th century ozone increase. Our results suggest that iodine’s impact on the Northern Hemisphere atmosphere accelerated over the 20th century and show a coupling between anthropogenic pollution and the availability of iodine as an essential nutrient to the terrestrial biosphere.
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Woittiez, J. R. W., H. A. van der Sloot, G. D. Wals, B. J. T. Nieuwendijk i J. Zonderhuis. "The determination of iodide, iodate, total inorganic iodine and charcoal-adsorbable iodine in seawater". Marine Chemistry 34, nr 3-4 (październik 1991): 247–59. http://dx.doi.org/10.1016/0304-4203(91)90006-i.
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Inamdar, Swaleha, Liselotte Tinel, Rosie Chance, Lucy J. Carpenter, Prabhakaran Sabu, Racheal Chacko, Sarat C. Tripathy i in. "Estimation of reactive inorganic iodine fluxes in the Indian and Southern Ocean marine boundary layer". Atmospheric Chemistry and Physics 20, nr 20 (26.10.2020): 12093–114. http://dx.doi.org/10.5194/acp-20-12093-2020.
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Abstract. Iodine chemistry has noteworthy impacts on the oxidising capacity of the marine boundary layer (MBL) through the depletion of ozone (O3) and changes to HOx (OH∕HO2) and NOx (NO∕NO2) ratios. Hitherto, studies have shown that the reaction of atmospheric O3 with surface seawater iodide (I−) contributes to the flux of iodine species into the MBL mainly as hypoiodous acid (HOI) and molecular iodine (I2). Here, we present the first concomitant observations of iodine oxide (IO), O3 in the gas phase, and sea surface iodide concentrations. The results from three field campaigns in the Indian Ocean and the Southern Ocean during 2015–2017 are used to compute reactive iodine fluxes in the MBL. Observations of atmospheric IO by multi-axis differential optical absorption spectroscopy (MAX-DOAS) show active iodine chemistry in this environment, with IO values up to 1 pptv (parts per trillion by volume) below latitudes of 40∘ S. In order to compute the sea-to-air iodine flux supporting this chemistry, we compare previously established global sea surface iodide parameterisations with new region-specific parameterisations based on the new iodide observations. This study shows that regional changes in salinity and sea surface temperature play a role in surface seawater iodide estimation. Sea–air fluxes of HOI and I2, calculated from the atmospheric ozone and seawater iodide concentrations (observed and predicted), failed to adequately explain the detected IO in this region. This discrepancy highlights the need to measure direct fluxes of inorganic and organic iodine species in the marine environment. Amongst other potential drivers of reactive iodine chemistry investigated, chlorophyll a showed a significant correlation with atmospheric IO (R=0.7 above the 99 % significance level) to the north of the polar front. This correlation might be indicative of a biogenic control on iodine sources in this region.
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Rohner, Fabian, Greg S. Garrett, Arnaud Laillou, Simone K. Frey, Ralf Mothes, Florian J. Schweigert i Lorenzo Locatelli-Rossi. "Validation of a User-Friendly and Rapid Method for Quantifying Iodine Content of Salt". Food and Nutrition Bulletin 33, nr 4_suppl3 (grudzień 2012): S330—S335. http://dx.doi.org/10.1177/15648265120334s309.
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Background Despite considerable progress made in the past decade through salt iodization programs, over 2 billion people worldwide still have inadequate iodine intake, with devastating consequences for brain development and intellectual capacity. To optimize these programs with regard to salt iodine content, careful monitoring of salt iodine content is essential, but few methods are available to quantitatively measure iodine concentration in a simple, fast, and safe way. Objective We have validated a newly developed device that quantitatively measures the content of potassium iodate in salt in a simple, safe, and rapid way. Methods The linearity, determination and detection limit, and inter- and intra-assay variability of this colorimetric method were assessed and the method was compared with iodometric titration, using salt samples from several countries. Results Linearity of analysis ranged from 5 to 75 mg/kg iodine, with 1 mg/kg being the determination limit; the intra- and interassay imprecision was 0.9%, 0.5%, and 0.7% and 1.5%, 1.7%, and 2.5% for salt samples with iodine contents of 17, 30, and 55 mg/kg, respectively; the interoperator imprecision for the same samples was 1.2%, 4.9%, and 4.7%, respectively. Comparison with the iodometric method showed high agreement between the methods ( R2 = 0.978; limits of agreement, −10.5 to 10.0 mg/kg). Conclusions The device offers a field- and user-friendly solution to quantifying potassium iodate salt content reliably. For countries that use potassium iodide in salt iodization programs, further validation is required.
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Amachi, Seigo, Koh Kimura, Yasuyuki Muramatsu, Hirofumi Shinoyama i Takaaki Fujii. "Hydrogen Peroxide-Dependent Uptake of Iodine by Marine Flavobacteriaceae Bacterium Strain C-21". Applied and Environmental Microbiology 73, nr 23 (12.10.2007): 7536–41. http://dx.doi.org/10.1128/aem.01592-07.
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ABSTRACT The cells of the marine bacterium strain C-21, which is phylogenetically closely related to Arenibacter troitsensis, accumulate iodine in the presence of glucose and iodide (I−). In this study, the detailed mechanism of iodine uptake by C-21 was determined using a radioactive iodide tracer, 125I−. In addition to glucose, oxygen and calcium ions were also required for the uptake of iodine. The uptake was not inhibited or was only partially inhibited by various metabolic inhibitors, whereas reducing agents and catalase strongly inhibited the uptake. When exogenous glucose oxidase was added to the cell suspension, enhanced uptake of iodine was observed. The uptake occurred even in the absence of glucose and oxygen if hydrogen peroxide was added to the cell suspension. Significant activity of glucose oxidase was found in the crude extracts of C-21, and it was located mainly in the membrane fraction. These findings indicate that hydrogen peroxide produced by glucose oxidase plays a key role in the uptake of iodine. Furthermore, enzymatic oxidation of iodide strongly stimulated iodine uptake in the absence of glucose. Based on these results, the mechanism was considered to consist of oxidation of iodide to hypoiodous acid by hydrogen peroxide, followed by passive translocation of this uncharged iodine species across the cell membrane. Interestingly, such a mechanism of iodine uptake is similar to that observed in iodine-accumulating marine algae.