Iodine

About: Iodine is a research topic. Over the lifetime, 8936 publications have been published within this topic receiving 139981 citations. The topic is also known as: I & element 53.

Iodine-induced thyrotoxicosis in apparently normal thyroid glands.

Abstract: Although iodine-induced thyrotoxicosis was reported to occur in patients with obvious underlying thyroid disorders, it is not known to occur in patients with apparently normal thyroid glands. From ten such cases evidence is presented that thyrotoxicosis: a) appeared during treatments by iodide or organic-iodine-containing drugs, in the absence of any past history of thyroid disorder; b) was accompanied by almost undetectable radioiodine uptake which nevertheless could be activated by TSH; c) subsided spontaneously within a few weeks or months after stopping the high intake of iodine; d) and left, after a period of hypothyroidism, an apparently normal thyroid gland which had resumed normal size, function, uptake, and suppressibility.

Experimental and modeling study of oscillations in the chlorine dioxide-iodine-malonic acid reaction

Abstract: At pH 0.5-5.0, a closed system containing an aqueous mixture of chlorine dioxide, iodine, and a species such as malonic acid (MA) or cthyl acetoacetate, which reacts with iodine to produce iodide, shows periodic changes in the light absorbance of I;. This behavior can be modeled by a simple scheme consisting of three component reactions: (I) the reaction between MA and iodine, which serves as a continuous source of I-; (2) the reaction between ClO,' and I-, which acts as a source of C102-: and (3) the self-inhibited reaction of chlorite and iodide that kinetically regulates the system. The fast component reaction bctwccn chlorinc dioxide and iodide ion was studied by stopped-flow spectrophotometry. The rate law is -(C102')/df = 6 X IO3 ( M-2 s-')(CIO,')(I-). A two-variable model obtained from the empirical rate laws of the three component reactions givcs a good dcscription of the dynamics of the system. The oscillatory behavior results not from autocatalysis but from the self-inhibitory character of the chlorite-iodide reaction.

UV−Vis Spectroscopy of Iodine Adsorbed on Alkali-Metal-Modified Zeolite Catalysts for Addition of Carbon Dioxide to Ethylene Oxide

Abstract: The basicity of alkali-metal-exchanged (Na, K, Cs) zeolites X and Y was probed by UV−vis diffuse reflectance spectroscopy of adsorbed iodine. The observed blue shift in the visible absorption spectrum of adsorbed iodine, compared to gaseous iodine, correlated well with the negative charge on the framework oxygen atoms calculated from the Sanderson electronegativity equalization principle. The blue shifts associated with iodine adsorbed on classical catalytic supports like silica, alumina, and magnesia suggest that the iodine adsorption technique for probing basicity is applicable to a wide variety of solids. Iodine was also adsorbed on X and Y zeolites containing occluded cesium oxide formed by decomposition of impregnated cesium acetate. However, the iodine appeared to irreversibly react on these strongly basic samples, possibly forming an adsorbed triiodide ion. As a complement to the adsorption studies, the activity of alkali-metal-containing zeolites for the base-catalyzed formation of ethylene carbon...

The Swiss Iodized Salt Program Provides Adequate Iodine for School Children and Pregnant Women, but Weaning Infants Not Receiving Iodine-Containing Complementary Foods as well as Their Mothers Are Iodine Deficient

Abstract: Background: If children and pregnant women in the population are iodine sufficient, it is generally assumed infants are also sufficient. But weaning infants may be at risk of iodine deficiency because iodized salt contributes little dietary iodine during this period. To fill this gap, iodine fortification of infant formula milk (IFM) and complementary foods (CF) is likely important. Objectives: The objective of the study was to first confirm that Swiss school children and pregnant women remain iodine sufficient and then to assess iodine status in infancy and the relative contribution of breast milk and IFM/CF to their iodine intakes. Methods: We measured urinary iodine concentrations (UIC) in national cross-sectional samples of: 1) pregnant women (n = 648); 2) school children (n = 916); 3) infants at three time points: at 3–4 d after birth and at 6 and 12 months (n = 875); and 4) breast-feeding mothers (n = 507). We measured breast milk iodine concentrations in the mothers, assessed iodine sources in infa...

Stability of iodine in iodized salt used for correction of iodine-deficiency disorders. II.

Abstract: The purpose of this study was to assess the effect of humidity and packaging materials on the stability of iodine in typical salt samples from countries with tropical and subtropical climates under controlled climatic conditions. Initially we examined eight samples. In the second phase we expanded the study to salts from 18 sources and attempted to correlate the observed stability with salt impurities naturally present in these samples. High humidity resulted in rapid loss of iodine from salt iodized with potassium iodate ranging from 30% to 98% of the original iodine content. Solid low-density polyethylene packaging protected the iodine to a great extent. High losses were observed from woven high-density polyethylene bags which are often the packaging material of choice in tropical countries. Impurities that provided moisture at the salt surface had the most deleterious effect. Although clear correlations were not obtained the presence of reducing agents hygroscopic compounds of magnesium and so forth seemed to have the most adverse effects on the stability of iodine. Surprisingly carbonates had little effect on stability over the range present in the samples. Packaging salt in low-density polyethylene bags which provided a good moisture barrier significantly reduced iodine losses and in most cases the iodine content remained relatively stable for six months to a year. The findings from this study indicate that iodine can be highly unstable and in order to ensure the effectiveness of local salt-iodization programmes countries should determine iodine losses from local iodized salt under local conditions of production climate packaging and storage. (authors)