Adverse Effects on the Thyroid of Chinese Pregnant Women Exposed to Long-Term Iodine Excess: Optimal and Safe Tolerable Upper Intake Levels of Iodine.

Ensuring optimal iodine nutrition in pregnant women is a global public health concern. However, there is no direct data on safe tolerable upper intake levels (ULs) for pregnant women. A cross-sectional study was performed to determine the ULs of pregnant women. A total of 744 pregnant women were enrolled in this study. The median (IQR) urinary iodine concentration (UIC) in pregnant women was 150.2 (87.6, 268.0) µg/L, and the urinary iodine excretion (UIE) over 24 h was 204.2 (116.0, 387.0) µg/day. Compared with those with a UIE figure of between 150-250 µg/day, the reference group, the prevalence of thyroid dysfunction was 5.7 times higher (95%CI: 1.7, 19.2) in pregnant women with a UIE figure of between 450-550 µg/day, and 3.9 times higher (95%CI: 1.5, 10.3) in pregnant women with a UIE figure of ≥550 µg/day. Compared with an estimated iodine intake (EII) of between 100-200 µg/day, the reference group, the prevalence of thyroid dysfunction was 4.3 times higher (95%CI: 1.3, 14.4) in pregnant women with a UIE figure of between 500-600 µg/day, and 3.6 times higher (95%CI: 1.5, 8.9) in pregnant women with UIE of ≥600 µg/day. In general, our cross-sectional study found that excessive iodine intake during pregnancy appears to directly increase the risk of thyroid dysfunction. Avoiding chronic iodine intakes of 500 µg/day or higher or having a UIE figure of ≥450 µg/day is recommended for pregnant women in China.

Saliva Iodine Concentration in Children and Its Association with Iodine Status and Thyroid Function.

CONTEXT: The effectiveness of saliva iodine concentration (SIC) in evaluating iodine status in children is not clear. OBJECTIVE: We aimed to explore associations between SIC and assessed indicators of iodine status and thyroid function. DESIGN: Cross-sectional study. SETTING: Primary schools in Shandong, China. PARTICIPANTS: Local children aged 8 to 13 years with no known thyroid disease were recruited to this study. MAIN OUTCOME MEASURES: Blood, saliva, and urine samples were collected to evaluate thyroid function and iodine status. RESULTS: SIC positively correlated with spot urinary iodine concentration (r = 0.29, P < 0.0001), 24-hour urinary iodine concentration (r = 0.35, P < 0.0001), and 24-hour urinary iodine excretion (r = 0.40, P < 0.0001). The prevalence of thyroid nodules (TN) and goiter showed an upward trend with SIC quantiles (P for trend < 0.05). Children with SIC <105 µg/L had a higher risk of insufficient iodine status (OR = 4.18; 95% CI, 2.67-6.56) compared with those with higher SIC. Those having SIC >273 µg/L were associated with greater risks of TN (OR = 2.70; 95% CI, 1.38-5.26) and excessive iodine status (OR = 18.56; 95% CI, 5.66-60.91) than those with lower SIC values. CONCLUSIONS: There is a good correlation between SIC and urinary iodine concentrations. It is of significant reference value for the diagnosis of iodine deficiency with SIC of less than 105 µg/L and for the diagnosis of iodine excess and TN with SIC of more than 273 µg/L. Given the sanitary nature and convenience of saliva iodine collection, SIC is highly recommended as a good biomarker of recent iodine status in school-aged children.

Establishing reference intervals for urine and serum iodine levels: A nationwide multicenter study of a euthyroid Chinese population.

CONTEXT: Urinary iodine (UI) is commonly used for evaluating iodine status, whereas serum iodine (SI) is more closely correlated with bioavailable iodine. However, no reliable reference intervals (RIs) for clinical use are available. We aimed to establish RIs for SI, UI, and a ratio of UI to urinary creatinine (U-Cre) applicable to the Chinese population. METHODS: This multicenter cross-sectional study enrolled 930 apparently healthy adults from six representative cities in China (Beijing, Dongying, Guiyang, Urumqi, Shenzhen, and Qiqihar) in 2017. Thyroid ultrasonography and thyroid function tests, including antithyroid antibody tests, were performed to exclude individuals with latent thyroid diseases. An iodine intake-related questionnaire survey was performed. SI and UI were measured using inductively coupled plasma-mass spectrometry. Possible influencing factors of iodine levels were evaluated using multiple regression analysis. RESULTS: Post-exclusion, the final analysis included 894 individuals. Seafood intake frequency was positively correlated with SI (standardized partial regression coefficient = 0.23) but not with UI and UI/U-Cre. SI was positively correlated with serum TT4 (Spearman correlation coefficient: 0.40), TT3 (0.23), and FT4 (0.18). SI and UI showed no age- or sex-specific variations. Significantly higher UI/U-Cre values were observed in Qiqihar than in Beijing, Guizhou, and Shenzhen. Shenzhen showed the lowest UI levels among all evaluated cities. With application of latent abnormal values exclusion procedurere, the RIs for SI, UI, and UI/U-Cre in the population were 36.0-79.3 µg/L, 19-385 µg/L, 22-450 µg/g, respectively. CONCLUSIONS: We established RIs for UI and SI among healthy Chinese individuals with no thyroid nodule or dysfunction.

Availability of adequately iodized salt at household level in Dessie and Combolcha Towns, South Wollo, Ethiopia.

BACKGROUND: Iodine deficiency disorder is the leading cause of mental retardation and poor economic performance in developing countries. Worldwide, universal salt iodization has been implemented to eliminate iodine deficiency. However, the adequacy of iodine in salts needs close monitoring to meet its intended goal and this study was aimed at investigating the adequacy of iodine in dietary salt at household level in Dessie and Combolcha Towns. METHODS: A community-based cross-sectional study was employed at household level in Dessie and Combolcha towns from January to February, 2017. Data were collected from 753 households using systematic sampling technique. The adequacy of iodine in salt was analyzed using rapid testing kit. Socio-demographic and economic, dietary sources, labeling, packaging, storage and cooking methods of household's characteristics were collected via questionnaire developed using open data kit tool and STATA version 12 was used for further statistical analysis. Ordinal Logistic regression was performed to assess associations between explanatory variables and the response variable. RESULTS: Nearly one-thrid (31.2%) of the households used inadequate iodized salt, which was below the World Health Organization recommendation level (≥15 ppm at the household level). Most of the respondents from Combolcha town (64.6%) were affected by inadequate use of iodized salt as compared to Dessie Town residents (22.2%). Being Dessie resident (OR = 2.53; 95% CI: 1.31-4.90), households with better socioeconomic status (OR = 2.54; 95% CI:1.10-5.87), site of labeling and packing (salt from open market (OR = 0.10; 95% CI: 0.04-0.23) and no exposure to sunlight (OR = 2.54; 95% CI:1.31-4.91) were the predictors of adequacy of iodized salt at household level. CONCLUSIONS: Availability of adequately iodized salt at the household level in the study area was low. There should be regular quality control and regulatory enforcement of salt iodization at production, labeling and packaging sites of small scale industries and at household level.

Iodine deficiency in pregnant women after the adoption of the new provincial standard for salt iodization in Zhejiang Province, China.

BACKGROUND: Zhejiang has achieved the goal of elimination of iodine deficiency disorders (IDD) via the implementation of universal salt iodization (USI) since 2011. Iodine content in household table salt decreased from the national standard (35 ppm) to the Zhejiang provincial standard (25 ppm) in 2012. It is crucial to periodically monitor iodine status in pregnant women because IDD in pregnancy have adverse effects on fetal neurodevelopment. METHODS: We carried out a cross-sectional study between April 2014 and September 2015 in the eight sentinel surveillance counties across Zhejiang Province, where IDD was previously known to be endemic. A total of 1304 pregnant women participated and provided a random spot urine sample and a household table salt sample. Urinary iodine concentration (UIC) was determined using arsenic-cerium catalytic spectrophotometry. Iodine content in salt was measured using a titration method with sodium thiosulphate. RESULTS: Overall, the median UIC of the total study population of pregnant women was 129.3 µg/L, with a higher UIC in inland (152.54 µg/L) and a lower UIC in coastal counties (107.54 µg/L). Household coverage of iodized salt was 94.6% and the rate of adequately iodized salt was 89.9%. CONCLUSIONS: Our results indicate deficient iodine status in the pregnant population of Zhejiang, according to the lower cut-off value of optimal iodine nutrition (150 µg/L) recommended by the World Health Organization. In addition to sustaining USI, more efforts are urgently needed to improve iodine intake in women during pregnancy, especially those residing in the coastal counties.

IODINE NUTRITION IN THE REPUBLIC OF ARTSAKH (NAGORNO KARABAKH).

OBJECTIVE: Iodine is a required nutrient for thyroid function. The mountainous terrain in the Republic of Artsakh (Nagorno Karabakh) in the south Caucasus suggests that it is likely to be endogenously deficient in iodine. The region is heavily dependent on neighboring Armenia for food imports including iodized salt. Since 2005, iodine is a government-sanctioned compulsory supplemental ingredient in salt in Armenia. However, there has never been a study of iodine nutrition in Artsakh. We sought to determine the level of iodine nutrition in Artsakh and the iodine content of table salt in the region. METHODS: Using a cross-sectional modified cluster model, we measured urine and salt iodine concentrations from a representative sample of children living in Artsakh. From 30 schools throughout the territory, we obtained 772 urine samples from children aged 8 to 10, and 323 samples of table salt. Repeat urine samples from 18.6% of participants were obtained. RESULTS: The median adjusted urinary iodine content was 203 µg/L (mean 206 µg/L, 95% confidence interval 202-210), within the range indicating sufficient iodine nutrition. There were small but statistically significant differences between the 8 administrative regions; however, there were no differences between individual sites. We found that 97.2% of table salt samples tested had iodine concentrations within the standard of 25 to 55 mg/kg. CONCLUSION: Among school-age children in Artsakh, iodine nutrition is adequate, and the salt is appropriately iodized. These results illustrate the remarkable success of the Armenian salt iodization program in providing sufficient but not excessive iodine to the mountainous territory of Artsakh. Abbreviation: UIC = urinary iodine concentration.

Development of Databases on Iodine in Foods and Dietary Supplements.

Iodine is an essential micronutrient required for normal growth and neurodevelopment; thus, an adequate intake of iodine is particularly important for pregnant and lactating women, and throughout childhood. Low levels of iodine in the soil and groundwater are common in many parts of the world, often leading to diets that are low in iodine. Widespread salt iodization has eradicated severe iodine deficiency, but mild-to-moderate deficiency is still prevalent even in many developed countries. To understand patterns of iodine intake and to develop strategies for improving intake, it is important to characterize all sources of dietary iodine, and national databases on the iodine content of major dietary contributors (including foods, beverages, water, salts, and supplements) provide a key information resource. This paper discusses the importance of well-constructed databases on the iodine content of foods, beverages, and dietary supplements; the availability of iodine databases worldwide; and factors related to variability in iodine content that should be considered when developing such databases. We also describe current efforts in iodine database development in the United States, the use of iodine composition data to develop food fortification policies in New Zealand, and how iodine content databases might be used when considering the iodine intake and status of individuals and populations.

Biomonitoring Equivalents for interpretation of urinary iodine.

Iodine is an essential nutrient whose deficiency or excess exposure can cause adverse health effects. The primary sources of iodine exposure in the general population are iodized salt, dairy products, bread and sea food. Urinary iodine concentrations (UIC) have been measured by Canadian Health Measures Survey (CHMS) and US National Health and Nutrition Examination Survey (NHANES). The Institute of Medicine (IOM), the US Agency for Toxic Substances and Disease Registry (ATSDR) and World Health Organization (WHO) have established exposure guidance values for nutrition (IOM Estimated Average Requirement (EAR), Recommended Dietary Allowance (RDA), WHO Recommended Nutrient Intake (RNI)) and toxicity (IOM Tolerable Upper Intake Level (UL); ATSDR Minimal Risk Level (MRL), WHO International Programme on Chemical Safety (IPCS) Tolerable Daily Intake (TDI)). Using a urinary excretion fraction of 0.9, Biomonitoring Equivalents (BE) for the EAR, RDA, UL and MRL were derived for adults (60, 100, 730 and 450 µg/L, respectively) and children (50, 80, 580 and 360 µg/L, respectively). The population median UIC values from NHANES and CHMS for adults (140-181, 122-126 µg/L, respectively) and children (232, 189 µg/L, respectively) were above the criteria for assessing iodine nutrition, indicating that US and Canadian populations are likely to have adequate population iodine nutrition. The median UIC from NHANES and CHMS do not exceed BE values derived from exposure guidance values for toxicity.

The legislative framework for salt iodization in Asia and the Pacific and its impact on programme implementation.

OBJECTIVE: Fortification of food-grade (edible) salt with iodine is recommended as a safe, cost-effective and sustainable strategy for the prevention of iodine-deficiency disorders. The present paper examines the legislative framework for salt iodization in Asian countries. DESIGN: We reviewed salt iodization legislation in thirty-six countries in Asia and the Pacific. We obtained copies of existing and draft legislation for salt iodization from UNICEF country offices and the WHO's Global Database of Implementation of Nutrition Actions. We compiled legislation details by country and report on commonalities and gaps using a standardized form. The association between type of legislation and availability of iodized salt in households was assessed. RESULTS: We identified twenty-one countries with existing salt iodization legislation, of which eighteen were mandatory. A further nine countries have draft legislation. The majority of countries with draft and existing legislation used a mandatory standard or technical regulation for iodized salt under their Food Act/Law. The remainder have developed a 'stand-alone' Law/Act. Available national surveys indicate that the proportion of households consuming adequately iodized salt was lowest in countries with no, draft or voluntary legislation, and highest in those where the legislation was based on mandatory regulations under Food Acts/Laws. CONCLUSIONS: Legislation for salt iodization, particularly mandatory legislation under the national food law, facilitates universal salt iodization. However, additional important factors for implementation of salt iodization and maintenance of achievements include the salt industry's structure and capacity to adequately fortify, and official commitment and capacity to enforce national legislation.

Re-establishment of normal radioactive iodine uptake reference range in the era of universal salt iodization in the Indian population.

BACKGROUND & OBJECTIVES: The reference radioactive iodine uptake (RAIU) values established in the 1970s in the era of widespread iodine deficiency were relatively high. Now, after four decades of successful Universal Salt Iodization (USI) programme in India, there is a need to re-establish these reference ranges. The present study was aimed to quantify the two-hour and 24-h RAIU values in iodine sufficient euthyroid individuals and validate the results in Graves' and Hashimoto's thyroiditis patients. METHODS: In this prospective study conducted from April 2012 to September 2013, euthyroid volunteers who consented for the investigations were enrolled in the study. Treatment-naive Graves' disease and Hashimoto's thyroiditis patients were recruited from the outpatient clinic. The investigations included neck ultrasonography, thyroid function tests, thyroglobulin (Tg), anti-Tg and anti-thyroid peroxidase antibody and urinary iodine concentration. RESULTS: Three different groups comprising 110 euthyroid volunteers, 38 Graves' and 17 Hashimoto's thyroiditis patients were enrolled in the study. The mean 2-h RAIU values for the euthyroid group, Hashimoto's thyroiditis and Graves' patients were 3.83±2.77, 4.22±3.41 and 32.67±15.93 per cent, and mean 24-h RAIU values were 12.75±5.51, 11.66±9.55 and 61.85±12.9 per cent, respectively. The mean thyroid volumes were 7.63±2.72, 7.81±1.67 and 20.76±12.56 ml for the euthyroid, Hashimoto's thyroiditis and Graves' disease groups and the mean spot urinary iodine concentrations were 9.0, 7.8 and 13.9 µg/dl in the three groups, respectively. The new reference range (95% confidence interval) for two-hour was 1-7 per cent and 24-h was 7-18 per cent. INTERPRETATION & CONCLUSIONS: Compared to the previous values, there was a considerable decrease in the RAIU values in euthyroid individuals. This was further corroborated with increase in the urinary iodine concentration and decrease in thyroid volume, attributed to successful USI programme. Further studies with a large sample from different parts of India need to be done to confirm these findings.

Lebanese children are iodine deficient and urinary sodium and fluoride excretion are weak positive predictors of urinary iodine.

PURPOSE: To assess iodine and fluoride status among Lebanese children. METHODS: A nationally representative cross-sectional study of 6- to 10-year-old schoolchildren was conducted using multistage cluster sampling. Spot urine samples were collected from 1403 children, and urinary iodine, fluoride, creatinine and sodium levels were measured. Salt samples from markets (n = 30) were tested for iodine concentration by titration. RESULTS: Median urinary iodine concentration was 66.0 µg/l, indicating mild deficiency, and almost 75 % of Lebanese children had a urinary iodine concentration (UIC) <100 µg/l. UIC was higher among children from private schools and in areas of higher socioeconomic status. Most salt samples were fortified at levels far below the legislated requirement, and 56 % of samples contained less than 15 ppm iodine. Fluoride-to-creatinine ratio (F/Cr) was 0.250 (0.159-0.448) mg/g. There were weak positive correlations between UIC and urinary sodium (r 2 = 0.039, P value <0.001) and UIC and urinary fluoride (r 2 = 0.009, P value <0.001). CONCLUSIONS: Lebanese elementary school children are iodine deficient due to inadequately iodized salt. The weak correlation between UIC and urinary sodium suggests most dietary iodine does not come from iodized salt. The poor correlation between UIC and urinary fluoride suggests that fluoride intake is not affecting iodine metabolism. Efforts are needed in Lebanon to improve industry compliance with salt fortification through improved monitoring and enforcement of legislation.

Serum thyroglobulin as a biomarker of iodine deficiency in adult populations.

OBJECTIVE: To clarify which factors may influence the serum Tg level in an adult population and how this may affect Tg as a biomarker of iodine deficiency (ID). DESIGN AND METHODS: Two identical cross-sectional studies were performed before (C1a: 1997-98, n = 4649) and after (C2: 2004-05, n = 3570) the Danish mandatory iodine fortification (IF) of salt (2000). Additionally, a follow-up study of C1a was performed after IF (C1b: 2008-10, n = 2465). The studies took place in two regions with mild (Copenhagen) and moderate (Aalborg) ID before IF. Serum Tg was measured by immunoradiometric method and investigated as outcome variable in multivariate models. RESULTS: Multiple factors were associated with serum Tg. Some were directly related to iodine intake (cohort, urinary iodine concentration (UIC) level and region), and some were likely mediators of iodine intake effects on Tg (thyroid nodularity, thyroid size and autonomy with low TSH). Others were caused by Tg assay interference (Tg-Ab positivity), aggravation of ID (childbirths and smoking) or TSH stimulation of the thyroid. Estimated 24-h urinary iodine excretion was a more sensitive predictor of Tg than UIC. Iodine supplement users had low median Tg values compared with nonusers both before and after IF. CONCLUSIONS: Multiple factors should be taken into consideration when evaluating Tg as a marker of ID in adult populations, and the Tg results may depend on the assay used. Still, Tg is a sensitive marker of ID. We suggest including a reference population with known sufficient iodine intake when Tg is used to evaluate ID.

Iodine nutritional status after the implementation of the new iodized salt concentration standard in Zhejiang Province, China.

BACKGROUND: Iodine deficiencies were prevalent in China until the introduction of universal salt iodization (USI) in 1995. In 2012, the standard salt iodine concentration was adjusted to 20-30 mg/kg. The success of USI for the control of iodine deficiency disorders requires monitoring its effect at a population level. METHODS: Two cross sectional surveys of a representative sample of children aged 8-10 years in Zhejiang Province were carried out in 2011 and 2013. Data on participants' socio-demographic characteristics were collected from the children using a structured questionnaire. Spot urine samples were collected and delivered to local Center for Disease Control and Prevention laboratory for measuring urinary iodine concentration. In 2011, out of 420 selected children aged 8-10 years, 391 were recorded and provided urine samples. In 2013, out of 1560 selected children aged 8-10 years, 1556 were recorded and provided urine samples. RESULTS: The median urinary iodine concentration of subjects in the 2013 survey was 174.3 µg/L, significantly lower than that of 2011(p = 0.000). The median urinary iodine concentration of subjects living in urban and rural areas in the 2013 survey was 169.0 µg/L, and 186.1 µg/L respectively, significantly lower than that of 2011 only for subjects living in urban areas (p = 0.000). There were no significant differences for subjects living in rural areas in the survey in 2011 and in 2013 (p = 0.086). CONCLUSIONS: At the time the new local iodization policy put forward, iodine nutrition was generally adequate in both urban and rural areas, suggesting that the new policy for adjusting the standard salt iodine concentration is effective. Our data also indicate that the reason people living in urban areas had a lower urinary iodine concentration than people in rural areas may be due to their preference for using non-iodized salt in the last 2 or 3 years. Maintaining USI at an appropriate level is an important part of preventing iodine deficiency disorders and should always be based on regular monitoring and comparison of urinary iodine concentration by province.

Reaching the poor with adequately iodized salt through the Supplementary Nutrition Programme and Midday Meal Scheme in Madhya Pradesh, India.

PROBLEM: In India, adequately iodized salt needs to be made accessible to the most marginalized. APPROACH: In an effort to provide adequately iodized salt to the most vulnerable, in 2009 Madhya Pradesh launched a state-wide initiative through two national flagship nutrition programmes: the Supplementary Nutrition Programme of the Integrated Child Development Services and the Midday Meal Scheme. Programme staff members were taught how to correctly store salt and monitor its iodine content. Field monitors assessed the iodine content of the salt in the common kitchens of participating schools and anganwadi centres monthly. LOCAL SETTING: Madhya Pradesh, a state in central India, is home to a substantial proportion of India's poor. In 2009, household coverage of adequately iodized salt in the state was nearly 90% among the richest but only about 50% among the poorest. RELEVANT CHANGES: Two hot meals prepared with adequately iodized salt were served daily for more than 21 days per month to approximately 89% of the 12,113,584 children aged 3 to 6 years enrolled in anganwadi centres (June 2011 to March 2012). One meal on school days was served to 78% of 5,751,979 primary-school children and to 79% of 2,704,692 secondary-school children (April 2011 to March 2012). Most of the kitchens visited in 2010 (79%) and 2011 (83%) were consistently using adequately iodized salt to prepare hot meals. LESSONS LEARNT: India has large-scale social safety net programmes for the poorest. Both national and state policies should mainstream the use of adequately iodized salt in these programmes.

Systematic review and cost analysis comparing use of chlorhexidine with use of iodine for preoperative skin antisepsis to prevent surgical site infection.

OBJECTIVE: To compare use of chlorhexidine with use of iodine for preoperative skin antisepsis with respect to effectiveness in preventing surgical site infections (SSIs) and cost. METHODS: We searched the Agency for Healthcare Research and Quality website, the Cochrane Library, Medline, and EMBASE up to January 2010 for eligible studies. Included studies were systematic reviews, meta-analyses, or randomized controlled trials (RCTs) comparing preoperative skin antisepsis with chlorhexidine and with iodine and assessing for the outcomes of SSI or positive skin culture result after application. One reviewer extracted data and assessed individual study quality, quality of evidence for each outcome, and publication bias. Meta-analyses were performed using a fixed-effects model. Using results from the meta-analysis and cost data from the Hospital of the University of Pennsylvania, we developed a decision analytic cost-benefit model to compare the economic value, from the hospital perspective, of antisepsis with iodine versus antisepsis with 2 preparations of chlorhexidine (ie, 4% chlorhexidine bottle and single-use applicators of a 2% chlorhexidine gluconate [CHG] and 70% isopropyl alcohol [IPA] solution), and also performed sensitivity analyses. RESULTS: Nine RCTs with a total of 3,614 patients were included in the meta-analysis. Meta-analysis revealed that chlorhexidine antisepsis was associated with significantly fewer SSIs (adjusted risk ratio, 0.64 [95% confidence interval, [0.51-0.80]) and positive skin culture results (adjusted risk ratio, 0.44 [95% confidence interval, 0.35-0.56]) than was iodine antisepsis. In the cost-benefit model baseline scenario, switching from iodine to chlorhexidine resulted in a net cost savings of $16-$26 per surgical case and $349,904-$568,594 per year for the Hospital of the University of Pennsylvania. Sensitivity analyses showed that net cost savings persisted under most circumstances. CONCLUSIONS: Preoperative skin antisepsis with chlorhexidine is more effective than preoperative skin antisepsis with iodine for preventing SSI and results in cost savings.

[Iodization of table salt and attitudes and habits in relation to the use of salt in general population].

INTRODUCTION: Combating nutritional deficiencies of micronutrients, such as iodine, represents a priority task of health care organizations. In 2003, the World Health Organization (WHO) published the publication: Global Prevalence of Iodine Deficiency Disorders (IDD), according to which some 2.2 billion people live in areas poor in naturally occurring iodine. Approximately 13% of the world population suffer from goitre--one of the IDD.The recommended iodine content in table salt is 20-40 mg/kg, which should satisfy the daily iodine requirements of an adult. OBJECTIVE: The authors sought to ascertain whether iodization of table salt in Montenegro was carried out in accordance with the existing legislature. An assessment was also carried out of the attitudes and habits of the population regarding the use of salt in nutrition and the level of awareness in relation to the relevance of table salt iodization. METHODS: The research was carried out in 2004 and was sponsored by UNICEF. A sample of 594 homes from the municipalities of Bar and Podgorica was chosen: 354 homes from urban and 240 from rural areas. The participants completed a questionnaire related to the daily use and intake of salt, as well as their understanding of the relevance of table salt iodization. Iodine content was tested in 15 samples of table salt at production level, 170 samples at retail level and 126 samples taken from domestic use. RESULTS: The analysis of table salt samples showed an optimal iodine level in 73.3% of samples from production, in 81.2% from retail, and in 73.0% from domestic use. A lower level of iodine was found in 8.8% retail samples and 15.1% samples from home use. A greater concentration of iodine was found in 26.7% production, 10.0% retail and 11.9% samples from domestic use. CONCLUSION: Although the application of the WHO programme has led to an improvement in iodization of table salt in Montenegro, both at production and retail levels, this still falls short of the standards recommended by WHO to combat IDD. The levels of iodine in table salt in domestic use also fail to comply with the WHO criteria for elimination of IDD.

Iodine nutrition in Brazil: where do we stand?

Brazilian legislation, since 1955, failed to achieve its objectives because the issue was not properly addressed: iodized salt was only available in endemic areas, at a low amount of 10 mg Iodine/kg salt. Lack of surveillance and cooperation were common errors. From 1982 to 1992, the INAN distributed potassium iodate to the industry free of charge, but it was abolished in 1991. Only four years later (1995) was a new law enacted effective in determining that all salt for human use should be iodized at levels established by the Health Authorities. During the period comprising 1998 to 2004, excessive iodination of salt (40 to 100 mg/kg) could lead to an increased prevalence of chronic autoimmune thyroiditis and iodine-induced hyperthyroidism. In 2003, the content of iodine/kg of salt was lowered to 20 to 60 mg I/kg salt. A national survey of schoolchildren is currently underway and will indicate the changes required for adequate iodine in salt for human use.

Iodine nutrition in Brazil: where do we stand? / Iodo nutricional no Brasil: como estamos?

Brazilian legislation, since 1955, failed to achieve its objectives because the issue was not properly addressed: iodized salt was only available in endemic areas, at a low amount of 10 mg Iodine/kg salt. Lack of surveillance and cooperation were common errors. From 1982 to 1992, the INAN distributed potassium iodate to the industry free of charge, but it was abolished in 1991. Only four years later (1995) was a new law enacted effective in determining that all salt for human use should be iodized at levels established by the Health Authorities. During the period comprising 1998 to 2004, excessive iodination of salt (40 to 100 mg/kg) could lead to an increased prevalence of chronic autoimmune thyroiditis and iodine-induced hyperthyroidism. In 2003, the content of iodine/kg of salt was lowered to 20 to 60 mg I/kg salt. A national survey of schoolchildren is currently underway and will indicate the changes required for adequate iodine in salt for human use.

A legislação para corrigir deficiência crônica de iodo no Brasil iniciou-se em 1955. O sal iodado seria distribuído somente em áreas endêmicas de bócio, com dose fixa de 10 mg Iodo/kg de sal. Na década de 1982 a 1992, o Instituto Nacional de Alimentação e Nutrição assumiu o Programa Nacional para a Deficiência Crônica de Iodo e forneceu o iodato de potássio a todos os produtores de sal. Em 1992, o INAN foi dissolvido. Nova legislação foi promulgada em 1995. A Anvisa ficou encarregada de supervisionar o teor de iodo em amostras de sal. No período de 1998 a 2004, o teor de iodo no sal foi elevado para 40 a 100 mg I/kg de sal. O excesso nutricional de iodo na população possivelmente aumentou a prevalência de tireoidite de Hashimoto e hipertireoidismo. Inquérito epidemiológico nacional (PNAISAL) em escolares, em execução, indicará as futuras determinações para a adição de iodo no sal.

Optimization and validation of an ion-pair RP-HPLC-UV method for the determination of total free iodine in rabbit plasma: application to a pharmacokinetic study.

An ion-pair reverse-phase high performance liquid chromatographic method with UV-vis detection has been developed for the determination of total free iodine in rabbit plasma after vaginal administration of povidone-iodine (PVP-I). Sample preparation was done by protein precipitation with acetonitrile in 96-well format and aspirin was used as the internal standard. The 100 microL sodium thiosulfate solution (5 g L(-1)) was added to 100 microL plasma sample before protein precipitation, to convert the total free iodine in plasma to iodide (I(-)). Separation was performed on a C(18) column (200 x 4.6 mm i.d., 5 microm). The mobile phase consisting of a mixture of water phase (containing 10 mmol L(-1) 18-crown-6 ether, 5 mmol L(-1) octylamine and 5 mmol L(-1) sodium dihydrogen phosphate, pH adjusted to 6.0 with phosphoric acid) and acetonitrile in the ratio 70:30 (v/v) was delivered isocraticly at a flow rate of 1.0 mL min(-1). The method was sensitive with a lower limit of quantification of 0.005 microg mL(-1), with good linearity (r(2) > 0.9990) over the linear range of 0.005-2 microg mL(-1). All the validation data, such as linearity, accuracy and precision, were within the required limits. The method was successfully applied to study the pharmacokinetic of PVP-I in rabbits after vaginal administration.