The impacts of marine-emitted halogens on OH radical in East Asia during summer

Relationships between oceanic emissions and air chemistry are intricate and still not fully understood. For regional air chemistry, a better understanding of marine halogen emission on hydroxyl (OH) radical is crucial. OH radical is a key species in atmospheric chemistry because it can oxidize almost all trace species in the atmosphere. In the marine atmosphere, OH level could be significantly affected by the halogen species emitted from the ocean. However, due to the complicated interactions of halogens with OH through different pathways, it is not well understood how halogens influence OH and even great uncertain in the signs of net effect. Therefore, in this study, we aim to quantify the impact of marine-emitted halogens (including Cl, Br, and I) through different pathways on OH in the high OH season by using WRF-CMAQ model with process analysis and state-of-the-art halogen chemistry in the East Asia Seas. Results show a very complicated response of OH production rate (POH) to marine halogen emissions. The monthly POH is generally decreased over the ocean with maxima of about 10–15 % in the Philippine Sea, but is increased in many nearshore areas with maxima of about 7–9 % in the Bohai Sea. In the coastal areas of southern China, the monthly POH could also decrease 3–5 % in the Greater Bay Area, but with a daytime hourly maximum decrease over 30 %. Analysis to the individual reactions using integrated reaction rate (IRR) show that the net change of POH is controlled by the competitions of three main pathways through different halogen species. Sea spray aerosols (SSA) and inorganic iodine gases are the main species to influence the strengths of these three pathways and therefore have the most significant impacts on POH. Both of these two types of species decrease POH through physical processes, while generally increase POH through chemical processes. In the ocean atmosphere, the controlling species are inorganic iodine gases and the complicated iodine chemistry determines the basic pattern of ΔPOH, while over the continent, SSA is the controlling species and the SSA extinction effect leads to the negative ΔPOH in the southern China. Our results indicate that marine-emitted halogen species have notable impacts over the ocean and have potential impact on the coastal atmospheric oxidation. The identified main (previously known or unknown) pathways and their controlling factors from different halogen species to OH radical explains the halogen-induced change of POH East Asia and also can be applied in other circumstances (e.g., different domains, regions, and emission rates).

Causes of different goiter rates with the same iodine deficiency among the pastoral and agricultural populations of Tibet: A geographical comparison

Background The residents of both the agricultural and pastoral areas of Tibet share the same iodine deficiency and iodine nutrition, but the rate of thyroid goiter was significantly higher in the agricultural areas than in the pastoral areas. This project sought to determine why the populations in the iodine-deficient pastoral areas show a lower rate of thyroid goiter. Methods Food frequency questionnaires (FFQs) and 24 h history recalls were adopted to investigate the dietary patterns of the residents of the agricultural and pastoral areas. Meat and milk samples were collected to measure their inorganic iodine, total iodine and thyroid hormone contents using ICP-MS, AsIII-Ce4+ catalytic spectrophotometry and the Siemens’ chemiluminescence method, respectively. The intake of protein, and the microelements, selenium and iron, was calculated according to their content in the food. Results The per capita daily intake of meat, dairy, and cereal in the pastoral areas was 116.7, 216.7, and 433.3 g, respectively, which are significantly higher than those in the agricultural areas (50.0, 72.2, and 375.0 g, respectively) (p < 0.05). The content of thyroid hormone in dried beef and milk in the pastoral areas was 62.6 and 13.5 µg/kg, respectively, which was significantly higher than those in the agricultural areas (25.1 and 4.1 µg/kg, respectively) (p < 0.05). The daily intake of thyroid hormone, protein and microelements, selenium and iron from foods by the residents of the pastoral areas were 10.5 µg, 99.6 g, 30.0 µg and 15.8 mg respectively, which was significantly higher than those in the agricultural areas (1.79 µg, 56.5 g, 23.8 µg and 13.2 mg, respectively) (p < 0.05). Conclusions The significantly high intake of the food-borne thyroid hormone by the residents of the pastoral area could be the main reason the residents in the pastoral areas show a lower rate of thyroid goiter than those in the agricultural area. Moreover, the relatively high intake of protein and trace elements, selenium and iron by residents in the pastoral area could be another important factor for reducing the goiter rates.

The effect of iodine deficiency on the course of recurrent respiratory infection in children living in the iodine deficient region

Background. The consequence of iodine deficiency is a decrease in the secretion of thyroid hormones, which adversely affects the immune system with the development of somatic and predisposition to frequent respiratory diseases. The purpose was to investigate the iodine supply of the body of children with recurrent respiratory infections (RRI) by studying the organification and inorganic fractions of iodine in the serum and excretion of iodine in the urine. Materials and methods. The study was conducted by simple sampling, taking into account the characteristics of the clinic course of respiratory disease. Clinical and laboratory and instrumental examination was performed in 60 children aged 3 to 11 years with a diagnosis of RRI. The concentration of iodine in urine, the level of inorganic and organification iodine in the blood were studied. Results. The clinical picture presented with the symptoms of intoxication, fever, and catarrhal symptoms typical of RRI. In children with severe RRI experienced a clear decrease in the iodine level to 57.34 μg/l (p < 0.05) and a decline in the blood content of total iodine and iodine organification by 31.12 and 39.11 % (p < 0.001), respectively. The concentration of inorganic iodine was significantly higher (p < 0.001). Such results indicate a “wrong” subcellular distribution of iodine into fractions in the inflammatory process caused by RRI. The children with detected iodine deficiency demonstrated a more severe course of RRI. There was a moderately negative relationship between the levels of organification and inorganic iodine (r = –0.515; p < 0.05) and a direct relationship between the blood concentrations of total and organification iodine (r = 0.899; p < 0.05). Conclusions. The course of RRI in patients with iodine deficiency is characterized by an increase in the level of inorganic iodine, a decrease in organification iodine and total iodine, the deepening of these changes correlates with the severity of the respiratory disease.

Biofortification of Sweetcorn with Iodine: Interaction of Organic and Inorganic Forms of Iodine Combined with Vanadium

Around the world, maize cultivation is an essential part of food systems for humans and animals. Effective reactions against the occurrence of diseases related to the deficiency of elements in the human diet are related to the biofortification of plant species of broad importance, including maize. The enrichment of maize with iodine is difficult due to the poor transport of this element to the plant’s generative organs. In marine algae, vanadium is part of the structure of the enzyme iodine-dependent peroxidase (vHIPO) that catalyzes the uptake of cellular iodine (I) and its volatilization as I2. The relationship between iodine and vanadium in higher plants, however, is not well-known. The aim of this research was to determine the effect of vanadium fertilization and the interactions of organic and inorganic iodine compounds with vanadium under soil application. In the pot experiment, NH4VO3 was applied to the soil in two doses of 0.1 and 1 μmol·dm−3 both separately and in combination, with the following iodine compounds: 5-iodosalicylic acid (5-ISA), 2-iodobenzoic acid (2-IBeA), potassium iodide (KI), and potassium iodate (KIO3). The iodine compounds were also applied independently to vanadium, while in the control combination, fertilization was performed without I and V. Iodine compounds were applied with doses calculated using the molar mass of this element (i.e., 10 μmol·dm−3 I). The highest level of iodine accumulation in grains (regardless of fertilization with V) was obtained after the application of organic compounds 5ISA and 2IBeA. A lower dose of vanadium (0.1 μmol·dm−3) in combination with KI and KIO3 increased the accumulation of iodine in leaves, roots, and grains compared to the combination without the additional application of vanadium. The combined application of vanadium in both doses with 2-IBeA most effectively stimulated the transport and accumulation of iodine to the maize grain. Under the combined application of 5-ISA and vanadium (10 μmol·dm−3), we observed the stimulating effect of this organic iodine compound on the accumulation of vanadium in the roots as well as the antagonistic effect of vanadium in combination with 5-ISA on the accumulation of iodine in the roots, leaves, and maize grain. Vanadium accumulated mainly in the roots, where the content of this element increased proportionally to its dose. The soil application of 5-ISA increased the total sugar content and vitamin C content in the grain.

Full latitudinal marine atmospheric measurements of iodine monoxide

Iodine compounds destroy ozone (O3) in the global troposphere and form new aerosols, thereby affecting the global radiative balance. However, few reports have described the latitudinal distribution of atmospheric iodine compounds. This work reports iodine monoxide (IO) measurements over unprecedented sampling areas from Arctic to the Southern Hemisphere and spanning sea surface temperatures (SSTs) of approximately 0 °C to 31.5 °C. The highest IO concentrations were observed over the Western Pacific warm pool (WPWP), where O3 minima were also measured. There, negative correlation was found between O3 and IO mixing ratios at extremely low O3 concentrations. This correlation is not explained readily by the “O3-dependent” oceanic fluxes of photolabile inorganic iodine compounds, the dominant source in recent global-scale chemistry-transport models representing iodine chemistry, and rather implies that “O3-independent” pathways can be similarly important in the WPWP. The O3-independent fluxes result in a 15 % greater O3 loss than that estimated for O3-dependent processes alone. The daily O3 loss rate related to iodine over the WPWP is as high as approximately 2 ppbv despite low O3 concentrations of ~10 ppbv, with the loss being up to 100 % greater than that without iodine. This finding suggests that warming SST driven by climate change may affect the marine atmospheric chemical balance through iodine–ozone chemistry.

Modelling the impacts of iodine chemistry on the northern Indian Ocean marine boundary layer

Recent observations have shown the ubiquitous presence of iodine oxide (IO) in the Indian Ocean marine boundary layer (MBL). In this study, we use the Weather Research and Forecasting model coupled with Chemistry (WRF-Chem version 3.7.1), including halogen (Br, Cl, and I) sources and chemistry, to quantify the impacts of the observed levels of iodine on the chemical composition of the MBL. The model results show that emissions of inorganic iodine species resulting from the deposition of ozone (O3) on the sea surface are needed to reproduce the observed levels of IO, although the current parameterizations overestimate the atmospheric concentrations. After reducing the inorganic emissions by 40 %, a reasonable match with cruise-based observations is found, with the model predicting values between 0.1 and 1.2 pptv across the model domain MBL. A strong seasonal variation is also observed, with lower iodine concentrations predicted during the monsoon period, when clean oceanic air advects towards the Indian subcontinent, and higher iodine concentrations predicted during the winter period, when polluted air from the Indian subcontinent increases the ozone concentrations in the remote MBL. The results show that significant changes are caused by the inclusion of iodine chemistry, with iodine-catalysed reactions leading to regional changes of up to 25 % in O3, 50 % in nitrogen oxides (NO and NO2), 15 % in hydroxyl radicals (OH), 25 % in hydroperoxyl radicals (HO2), and up to a 50 % change in the nitrate radical (NO3), with lower mean values across the domain. Most of the large relative changes are observed in the open-ocean MBL, although iodine chemistry also affects the chemical composition in the coastal environment and over the Indian subcontinent. These results show the importance of including iodine chemistry in modelling the atmosphere in this region.

The state of iodine supply of prepubertal children living in the Northern Bukovina

Background. In Bukovina, depending on climatic and geographical zones, there is a mild and moderate degree of iodine deficiency. Assessment of urinary inorganic iodine excretion allows monitoring of the epidemiological situation regarding the severity of iodine deficiency in the region. The purpose was to assess the indicators of ioduria in prepubertal children living in the Northern Bukovina (Chernivtsi region). Materials and methods. As part of a 20-cluster analysis of the prevalence of goiter among the pediatric population of Chernivtsi region, 1,973 children aged 7 to 12 years were examined and the concentration of inorganic iodine in a single portion of urine was determined in 197 children. The obtained results were processed by the method of statistical variation and correlation analysis. Results. Manual palpation examination showed a significant incidence of goiter among children in Bukovina — 17.6 %. Thyromegaly among children of the reference group occurred in 15.1 % of cases. The median ioduria in the examined population is generally 60.4 μg/l. The average prevalence of iodine deficiency was 59.70 ± 1.82 %, the incidence of severe iodine deficiency did not exceed 5.22 ± 1.30 %. Analyzing the degree of iodine supply of children depending on the geographical areas of residence, we conclude that children li­ving in the plains and children from Chernivtsi have mild iodine deficiency (median ioduria is 72.2 and 70.4 μg/l, respectively), and children from mountainous areas — moderate iodine deficiency (median ioduria is 42.9 μg/l). The average prevalence of iodine deficiency was 59.70 ± 1.82 %, and excessive iodine in the urine — 18.70 ± 2.49 %. Moreover, the incidence of severe iodine deficiency did not exceed 5.22 ± 1.30 %. Conclusions. In most children living in Northern Bukovina, the median ioduria is reduced. In 18.7 % of children, the iodine content is more than 300 μg/l, which requires further monitoring.

Social and hygienic characteristics of children from the iodine deficiency region

Background. Determining the social and hygienic patterns of children’s health is an important scientific and methodological task of pediatrics, the solution of which makes it possible to manage health processes. Natural factors that affect health include iodine deficiency in environmental components. Nowadays in 19 countries, including Ukraine, the issue of iodine deficiency remains relevant. The purpose was to analyze social and hygienic factors in schoolchildren from the iodine deficiency region. Materials and methods. A survey of schoolchildren (n = 1,973) and their parents (n = 655) was conducted, we have examined 397 children aged 10–12 years from 7 districts of the Chernivtsi region. The concentration of inorganic iodine in a single urine portion was determined in 197 children, salt samples were tested using a rapid test. Results. In 2017, 56.1 % of parents-respondents did not know about the problem of iodine deficiency, and in 2019 — 28.2 %. Out of 397 salt samples taken from households, the presence of iodine was found in 133 (33.5 %) and 45 (41.3 %) of 109 samples taken from trade establishments. Of 509 samples labeled as iodized salt, only 35 % contained iodine and 65 % did not meet the requirements. The hygienic assessment of the balance of children’s diet revealed significant violations that may contribute to the development of iodine deficiency. Of 1,973 respondents, 15.7 % eat natural products. A disharmonious style of family upbringing dominated, which changes the emotional and mental state of a child. The median ioduria in the examined population is in general 58.1 ± 3.2 μg/l, the frequency of goiter among prepubertal children of Bukovinian region is 17.2 %. Two or more concomitant diseases, asthenic, neurotic and affective disorders were detected in 75.5 % of schoolchildren. Conclusions. Low public awareness, sale of iodized salt on the consumer market, which does not meet hygienic standards for iodine content, low motivation to use iodized salt on the background of iodine deficiency, even mild, are additional risk factors for iodine deficiency in schoolchildren of Chernivtsi region.

Temperature dependent kinetics of the reaction of ozone with iodide

&lt;p&gt;Iodine in the atmosphere results from emissions of precursors from the oceans [1, 2] and undergoes continuous multiphase cycling. This cycling also prevents poorly soluble gaseous iodine species from removal by wet deposition. Thus, tropical convective outflow can even inject inorganic iodine into the lower stratosphere [3]. In the troposphere [1] and in the stratosphere [4], iodine appears in the gas- and particulate phase. In both compartments, particulate iodine exists not only in oxidized (as iodate) but also in reduced (as iodide) form [1, 4]. As iodide reacts with ozone in the aqueous phase [2] (which is also a major process related to iodine emission from the oceans), the reaction of ozone with iodide is one wheel of the cycles in the troposphere and may even represent a direct ozone sink in the stratosphere. However, only few kinetic data exist for this reaction. The temperature dependence of the reaction rate coefficient between 275 and 293 K was determined once and extrapolation of its value below 275 K rely on an activation energy estimate with an error of about 40 % [5]. Therefore, we performed laboratory experiments to extend the temperature range of the rate coefficient determination. We used a trough flow reactor [6] for our measurements and analyzed the data with a quasi steady state resistance model [7] to determine the essential physical parameters describing the reaction kinetics and their temperature dependence. Our results help to increase the understanding of atmospheric iodine chemistry and to better assess iodine&amp;#8217;s impact on ozone in both, the troposphere and the stratosphere.&lt;/p&gt;&lt;p&gt;Bibliography&lt;br&gt;[1]&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160; A. Saiz-Lopez et al., Chem. Rev., &lt;strong&gt;112&lt;/strong&gt;, 3 (2012)&lt;br&gt;[2]&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160; L. J. Carpenter et al., Nat. Geosci., &lt;strong&gt;6&lt;/strong&gt; (2013)&lt;br&gt;[3]&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160; A. Saiz-Lopez et al., Geophys. Res. Lett., &lt;strong&gt;42&lt;/strong&gt;, 16 (2015)&lt;br&gt;[4]&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160; T. K. Koenig et al., PNAS, &lt;strong&gt;117&lt;/strong&gt;, 4 (2020)&lt;br&gt;[5]&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160; L. Magi et al., J. Phys. Chem. A, &lt;strong&gt;101&lt;/strong&gt; (1997)&lt;br&gt;[6]&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160; L. Artiglia et al., Nat. Commun., &lt;strong&gt;8&lt;/strong&gt; (2017)&lt;br&gt;[7]&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160; M. Ammann et al., Atmos. Chem. Phys., &lt;strong&gt;13&lt;/strong&gt; (2013)&lt;/p&gt;

Very rare case of Graves’ disease with resistance to methimazole: a case report and literature review

Background Methimazole (MMI) is used to treat hyperthyroidism in Graves’ disease. It is rare to encounter patients in whom hyperthyroidism cannot be controlled using high doses of MMI. Case presentation: A 21-year-old woman was referred to our hospital because of MMI-resistant Graves’ disease. Although her MMI dose had been increased to 120 mg/day, her serum thyroid hormone concentration was too high to be measured. Additional therapy with lithium carbonate, and then with dexamethasone and inorganic iodine, was initiated. After 14 days, the patient’s serum thyroid hormone concentration normalized, while she was taking 150 mg/day MMI, 800 mg/day lithium carbonate, 6 mg/day dexamethasone and 306 mg/day inorganic iodine, and total thyroidectomy was then performed. The patient was discharged 8 days after the thyroidectomy and experienced no major complications. Conclusions We have presented a rare case of Graves’ disease that was resistant to high-dose MMI. Combination therapy of MMI with lithium carbonate, dexamethasone and inorganic iodine may represent a therapeutic option for the preoperative preparation of patients with MMI-resistant Graves’ disease.