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Objective: To reveal the relationship between iodine nutrition and the change of spectrum on thyroid diseases through comparing the different iodine environments pre- and post- the universal salt iodization(USI)campaign., Methods: To compare the urinary iodine concentration between 1000 normal people and 5998 patients with thyroid disease who had undergone surgical operations, from 4 major cities, including iodine deficient and rich areas of Guangxi Zhuang Autonomous Region., Results: After USI was put into practice, the urinary iodine concentration of patients with thyroid appeared higher than those of normal people(324.3 µg/L vs. 238.5 µg/L, P < 0.05). The urinary iodine concentrations of nodular goiter,Graves disease, toxic nodular goiter, thyroid papillary carcinoma and Hashimoto's thyroiditis were higher than those before the USI was taken(263.8 µg/L vs. 69.75 µg/L, 289.7 µg/L vs. 228.3 µg/L, 346.8 µg/L vs. 268.4 µg/L, 350.3 µg/L vs. 316.2 µg/L and 378.5 µg/L vs. 305.8 µg/L). The proportions of toxic nodular goiter, thyroid papillary carcinoma and Hashimoto's thyroiditis appeared as 7.59% vs. 4.80%, 5.85% vs. 4.02% and 3.88% vs. 2.46%, all higher than those before the implementation of USI, except the nodular goiter which showed a reduction (63.56% vs. 69.75%)., Conclusion: The spectrum of thyroid diseases appeared an obvious change in Guangxi within the last 10-year implementation of USI. However, the excessive intake of iodine might serve as a risk factor for toxic nodular goiter, thyroid papillary carcinoma and Hashimoto's thyroiditis.

Objective: To evaluate the iodine nutrition level of population in Zhejiang province and to analyze the relevant influencing factors from 2009 to 2011., Methods: From October 2009 to October 2011, a total of 19 517 subjects were recruited in this cross sectional survey, by multistage stratified cluster random sampling method. The subjects were all living over three years in Zhejiang province. The basic information and life styles were interviewed by questionnaires; and the samples of drinking water, edible salt and urines were separately collected from the subjects to test the content of iodine. In total, 16 228 subjects answered the questionnaire, and 265 samples of drinking water, 7811 samples of edible salt and 19 517 samples of urine were collected. Then, we analyzed the distribution of iodine in water, edible salt and urine samples, as well as the relevance., Results: The median (25% - 75% percentile) of water iodine was 2.42 (1.17 - 6.28) µg/L in drinking water among Zhejiang residents; while separately 2.79 (1.60 - 6.87) µg/L in city and 2.04 (1.03 - 5.29) µg/L in country side (Z = 2.07, P < 0.05). The figures turned out to be 2.17 (1.22 - 5.73) µg/L, 2.77 (1.88 - 6.87) µg/L, and 1.40 (0.77 - 5.65) µg/L, respectively, in coastal areas, coastal periphery areas and inland areas (χ(2) = 11.16, P < 0.05). The median (25% - 75% percentile) of salt iodine was 28.80 (22.93 - 32.40) mg/kg; while separately 29.00 (24.50 - 32.60) mg/kg and 28.50 (13.90 - 32.29) mg/kg in city and country side (Z = 6.32, P < 0.05). The figures turned out to be 25.19 (0.00 - 30.20) mg/kg, 29.00 (26.60 - 31.70) mg/kg and 32.40 (28.94 - 36.30) mg/kg, respectively, in coastal areas, coastal periphery areas and inland areas (χ(2) = 1581.62, P < 0.05). The coverage rate of iodized salt was 79.54% (6213/7811) in all province. The urinary iodine median was 160.74(97.20 - 247.00) µg/L, while the urinary iodine median in pregnant women was 137.99 (82.40 - 215.30) µg/L, lower than the recommended optimal levels, which was 150 - 249 µg/L. The figures turned out to be 153.45(92.00 - 237.50) µg/L in city and 168.00 (102.18 - 257.00) µg/L in country side (Z = -9.25, P < 0.05); while in coastal, coastal periphery place and inland areas, the median were separately 156.00 (94.29 - 242.80) µg/L, 150.14 (94.70 - 227.00) µg/L and 187.70 (109.00 - 276.80) µg/L (χ(2) = 194.12, P < 0.05). The analysis of relevance between urine iodine, water iodine and iodized salt showed that the urine iodine would increase as long as the iodized salt increased; and the difference had statistical significance (χ(2) = 440.88, P < 0.01). And there were no relevance between urine iodine level and the water iodine level (χ(2)cmh = 0.57, P = 0.45). The analysis of the influencing factors showed that education background (χ(2) = 14.17, P < 0.05), different styles of career (χ(2) = 16.15, P < 0.01) and diet habits (χ(2) = 108.63, P < 0.01) could influence the level of urine iodine., Conclusion: Iodine was deficient in Zhejiang province. The nutrition level of iodine was fine in Zhejiang in 2009, however, the coverage rate of iodine was commonly low in coastal areas, especially the pregnant women suffered from iodine deficiency. In our study, the factors influencing the urine iodine level included iodized salt, age, education background and diet habits.

Iodine deficiency disorders were prevalent in China until the introduction of universal salt iodization in 1995. Concerns have recently arisen about possible excess iodine intake in this context. To document iodine intake and the contribution from iodized salt in China, we surveyed dietary iodine intake during China's nationally representative 2007 total diet study (TDS) and during an additional TDS in 4 coastal provinces and Beijing in 2009. Iodine intake was broken down by age and sex in 2009. Mean daily iodine and salt intake and the contribution from different food and beverage groups (and in 2009, individual items) was measured. The iodine in food cooked with iodized and noniodized salt was also assessed. The mean calculated iodine intake of a standard male in China was 425 μg/d in 2007 and 325 μg/d in coastal areas in 2009, well below the upper limit (UL) in all provinces. In 2009, iodine intake was above the UL in only 1-7% of age-sex groups, except among children (18-19%). A concerning number of individuals consumed less than the WHO-recommended daily allowance, including 31.5% of adult women. Salt contributed 63.5% of food iodine, and 24.6% of salt iodine was lost in cooking. Overall salt consumption declined between the surveys. Salt iodization assures iodine nutrition in China where environmental iodine is widely lacking. The risk of iodine excess is low, but planned decreases in salt iodization levels may increase the existing risk of inadequate intake. Regular monitoring of urinary iodine and more research on the impact of excess iodine intake is recommended.

Objectives: IDD info, a new software for managing survey data of Iodine Deficiency Disorders (IDD), is presented in this paper. IDD Info aims to create IDD project databases, process, analyze various national or regional surveillance data and form final report. It has series measures of choosing database from existing ones, revising it, choosing indicators from pool to establish database and adding indicators to pool. It also provides simple tools to scan one database and compare two databases, to set IDD standard parameters, to analyze data by single indicator and multi-indicators, and finally to form typeset report with content customized., Methods: IDD Info was developed using Chinese national IDD surveillance data of 2005. Its validity was evaluated by comparing with survey report given by China CDC., Results: The IDD Info is a professional analysis tool, which succeeds in speeding IDD data analysis up to about 14.28% with respect to standard reference routines. It consequently enhances analysis performance and user compliance., Conclusions: IDD Info is a practical and accurate means of managing the multifarious IDD surveillance data that can be widely used by non-statisticians in national and regional IDD surveillance., (Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.)

Iodine intake affects the occurrence of disease in a population. Excessive iodine intake may be caused by a high iodine content of drinking water. Tap water in few locations in Europe contains up to 139 microg/L mostly bound to humic substances, probably leaching from marine sediments in the aquifers. Even higher iodine contents have been found in Chinese waters, previously shown to associate with goitre and hypothyroidism. The aims were to elucidate speciation of high iodine groundwater from deep wells in China and to compare with high iodine waters from Europe. Water was sampled from eight wells in five villages along Bohai Bay, China. Macro-molecules and low molecular weight (MW) substances were separated by size exclusion chromatography (high performance liquid chromatography, Superose 12 HR 10/30, buffer 0.1 M Tris, pH 7.0). Organic material was evaluated by A280 and iodine in fractions measured by the Ce/As method after alkaline incineration. Iodine content of well water varied from 135 to 880 microg/L (median 287 microg/L). The amount of organic material in water was low with A280, <1-5 mAU. The chromatographic traces were similar between samples: One peak of iodine eluted around K (AV) 0.65 corresponding to MW 5 kDa (humic substances) and one peak at V (total) (iodide/low MW substances). The fraction of iodine in macro-molecules, suggested to be humic substances, varied from 8% to 70% (median 27%). Iodine and peak absorbance were associated (p = 0.006). In conclusion, iodine in iodine-rich deep well water in northern China may have marine origin and may associate with humic substances, comparable to shallow well iodine-rich water in Europe. High iodine intake from iodine-rich water suggests the cause of endemic goitre and hypothyroidism in some areas in China being iodine.

In 1993, the State Council of China announced the policy to virtually eliminate iodine-deficiency disorders (IDD) by 2000 and adopted universal salt iodization (USI) as the national strategy. Biennial province-based monitoring from 1995 onward aimed at capturing the use and iodine content of household salt, along with urinary iodine concentrations among schoolchildren from the same households. This paper reports on the progress made in China toward the goal of virtually eliminating iodine-deficiency disorders on the basis of 85 population-representative surveys in China's provinces during 1995--99. The percentage of households using adequately iodized salt (iodine > or = 20 mg/kg) increased from 43.1 % in 1995, to 82.2% in 1997, to 89.0% in 1999. In 1999, at least 90% of the households in 15 (48%) of the 31 provinces used adequately iodized salt, and a median urinary iodine concentration of less than 100 microg/L in children was reported in only one province. Across provinces, the median urinary iodine concentrations in children were positively correlated in each survey year with the median household salt iodine contents (combined r(s) = 0.74, p < .001) and with the proportions of households using adequately iodized salt (combined r(s) = 0.81, p <.001). Also in each survey year, the percentage of children with urinary iodine concentrations of at least 300 microg/L was correlated (combined r(s) = 0.69, p < .001) with the proportion of households using salt with iodine content of at least 40 mg/kg. The median urinary iodine concentration in children had reached 300 microg/L or more in 13 provinces (42%) by 1999. In a little more than five years, then, China has achieved outstanding progress toward the goal of virtual elimination of IDD through USI. Policy recommendations include improvement of quality assurance by salt manufacturers, along with a modest reduction in the mandated salt iodization levels.

Objectives: This study assessed the relation of iodine content of household water to thyroid size and urinary iodine excretion in an area with high iodine concentration in the water., Methods: The iodine content of household water and indicators of iodine status (thyroid size and urinary iodine level) were assessed in selected villages in Jiangsu Province, China., Results: Water iodine levels were positively correlated with urinary iodine levels and indicators of thyroid size at the township level., Conclusions: Excess iodine in household water was the likely cause of endemic goiter and elevated urinary iodine levels in the study area. This finding affects public health policy on the institution of universal salt iodization for the elimination of iodine deficiency disorders.

To verify the existence and reveal the epidemiological characteristics of endemic iodide-induced goiter in Jiangsu Old Yellow River flooded plain, 12 spots were selected in this survey. The results showed that the total goiter rate of 22.18% by palpation and 12.83% by B-ultrasound which surpassed the 5%-cutpoint-recommended jointly by WHO/UNICEF/ICCIDD. The urinary iodine median was 962 micrograms/L in 607 samples. The average 24 hours I31iodine-emissivity ratio was 4.6 +/- 0.3% with most of the serum TSH, T4, T3 within normal ranges. Of 1049 water samples in 65 towns, 771 had iodine content over 300 micrograms/L with water iodine concentration over 300 micrograms/L in 52 towns. These findings suggested that goiter in this plain had been endemic which related to excessive iodine in shallow well water. Heavy load of iodine over general population was noticed.

Dun Hua is a district where endemic goiter has been prevalent. Residents commenced to eat iodined salt ten years ago. We studied 469 people in this district and discovered that the incidence of endemic goiter had somehow come down but still kept 10.4%. However, the incidence of thyroid cancer went up to 1.9% with the incidence of thyroiditis 0.85%. Pathological characteristic of endemic goiter frequently appeared adenoniatoid feature with some atypical hyperplasia follicles which facilitates the cancerization in the fibrigenic part. Reasons accounted for the endemic goiter occurrance might not only relate to the insufficient intake of iodined salt but also to the increase of iodine excretion from the body. The increase of iodine excretion may be related to the factors as varieties of subsidiary food and vegetables as well as personal habitualness on food and drinks.

Intelligence in children without iodine supplement during their fetal and infant periods, and in those born three to four years after the implementation of stable supply of iodized salt in the areas with endemic cretinism and goiter was tested with Standord-Binet method. Results indicated there existed a lot of mental retarded children in the iodine-deficiency areas, with most of them born before the implementation of iodine supplement. In order to study the changes of intelligence development in children probably induced by stable supply with iodine, the tested children living in the areas with endemic cretinism were followed-up for two years, and no improvement in children's intelligence could been seen. It suggested that impairment to children's intelligence development caused by iodine deficiency during their fetal and infant periods was irreversible.

An investigation on children's intelligence and the metabolism of iodine and fluorine in high iodine and fluorine regions was carried out. The results were as follows. In high iodine and high fluorine areas, the thyroid enlargement prevalence rate among inhabitants and that among children were 3.8% and 29.8%, respectively. The dental fluorosis prevalence rate among inhabitants and that among children was 35.48% and 72.9%, respectively. The pupils' average intelligence quotient (IQ) was 76.67 +/- 7.75, slightly lower than the control point, but that of low intelligent pupils was 16.7%. The urinary iodine and urinary fluoride were 816.25 +/- 1.80 micrograms/L and 2.08 +/- 1.03 mg/L, respectively, markedly higher than the control point. The thyroid iodine-131 (131I) uptake rate was markedly lower than the control point. The values at 3 h and 24 h were 9.36 +/- 1.55% and 9.26 +/- 4.63%, respectively. The serum TSH was obviously higher than the control point. These results indicate that high iodine and high fluorine exert severe damage to human body.

A study to determine the prevalence of goitre and abnormal thyroid status during pregnancy in Malaysian women was conducted. Two hundred and three women (Malay = 85, Chinese = 47 and Indian = 71) in the third trimester and with no known thyroid disease were studied. There was a marked racial disparity in the prevalence of goitre: Indian 61%, Malay 28% and Chinese 29% (p = 0.001). The serum thyrotropic hormone (TSH) was significantly higher in Indians (median: 1.36 uIU/ml) compared to Malays (1.14 uIU/ml, p = 0.009). The serum albumin was also significantly lower in Indians (mean +/- sd; 36.12 +/- 3.9 mmol/l) compared to Malays (39.3 +/- 4.8 mmol/l) or Chinese (39.1 +/- 5.2) (p < 0.001). Thyroid antibody was detected in 14.6% of these women with no significant racial difference in its prevalence. Three women were found to be thyrotoxic but none were hypothyroid. This study found a high prevalence of goitre among the pregnant Indian women, probably related to the protein malnutrition state. The high prevalence of positive thyroid antibody in our population indicates that a high percentage of women are at risk of developing postpartum thyroiditis.

Thyroid status was examined in children from two villages in central China where the iodine concentrations in drinking water were 462.5 and 54 micrograms/l. Goitres were present in 65% (n = 120) and 15.4% (n = 51), respectively. All children in both groups were clinically euthyroid and neurologically normal. Growth measurements and intellectual performance were similar in the two groups. Children from the high-iodine village had a lower mean serum triiodothyronine and higher serum free thyroxine and serum thyroid-stimulating hormone concentrations than the children from the control village. 2 cases of overt hypothyroidism were detected in the high-iodine village.