OBJECTIVETo draft out the simplified scheme of iodized salt monitoring program to compare with the current scheme, and to study its feasibility.

METHODS8 counties from 4 provinces were selected at different coverage rate of iodized salt. Conduct the monitoring program using the current scheme and the simplified scheme, then compare the results.

RESULTSThe monitoring results of the current scheme showed the coverage rate of iodized salt and adequate iodized salt were 88.1% and 84.8% and the data of the simplified scheme were 85.2% and 79.8% respectively. Five counties reached above 90% of both the coverage rates of iodized salt and adequate iodized salt and the results showed no significant difference between the two schemes. The rates of other three counties were low, and the difference was significant between Dulan and Linxia counties. To the whole samples, the difference was also significant.

CONCLUSIONThe simplified scheme could be applied to those that the coverage rate of iodized salt was quite high or the non-iodized salt was well-distrbuted. However, for those areas with low coverage rate, it might not be suitable. As for the whole nation, it might not be popularized due to the gap of coverage rate between western and eastern areas.

China ; Iodine ; analysis ; Sodium Chloride, Dietary ; analysis

OBJECTIVETo investigate the amount of daily iodine intake in the diet of the target population in drinking water with areas of excessive iodine after stopping supply of iodized salt, to provide evidence for developing strategies on control and prevention of excessive iodine.

METHODS335 objectives were selected by a two-stage sampling method in 4 administrative villages with different iodine contents in drinking water. The amount of drinking water intake and dietary survey for 335 people were done by a door-to-door survey,while the iodine contents in the drinking water of each selected family, local staple food and vegetable were measured.

RESULTSThe median level of iodine in drinking water was 431.5 microg/L while the daily amount of iodine intake among the three groups of waters with different iodine contents were all greater than RNI. The daily iodine intake of local people was all greater than UL in the areas where the water iodine contents were more than 300 microg/L. It was of statistical sense that the iodine mean intake per capita per day of the three groups differed at different water iodine levels (P < 0.01). The iodine mean intake per capita per day of the three groups of different water iodine levels increased along with water iodine and showed a uptrend (P < 0.01). 83.2%-98.7% of the daily iodine intake of the three groups was from drinking water and 1.3%-16.8% came from food. The iodine intake had high-positive correlation relation with the content of water iodine (P < 0.01).

CONCLUSIONIt was concluded that drinking water was the main source of iodine intake in areas with iodine excessive water by the percentage of over 80%. It was necessary to adopt measures to improve the quality of water to decrease the iodine content other than just stopping supplies of iodized salt in the areas where the water iodine contents were greater than 300 microg/L, in order to prevent and control excessive intake of iodine.

China ; Diet ; Humans ; Iodine ; analysis ; Sodium Chloride, Dietary ; Water Supply

OBJECTIVEWe aim to describe the environment iodine concentration in salt, water and soil along Zhejiang Province coast in the China foreland. It will be helpful for us to judge whether this area is insufficient in iodine and universal iodized salt is necessary or not.

METHODSWe collected iodized salt samples, drinking water samples (tap water in the towns, and well water or spring water in the villages), water samples from different sources (ditches, lakes, rivers) and soil samples through random sampling in June, 2005. Salt, water and soil iodine was detected by arsenic-cerium redox method. Statistical analysis was expressed as mean+/-SEM by Windows SPSS 13.0.

RESULTS(1) The iodine concentration in salt was 27.9+/-4.33 mg/kg (n=108). (2) Seventy-five water samples were collected. The water iodine value was 0.6-84.8 microg/L (mean of 11.66 mug/L). The watershed along the Qiantang River has significantly higher iodine content than the water in Lin'an in mountain area (P<0.01). The iodine content and mean iodine content of tap water, well or spring water and natural water sources were 4.30+/-2.43 microg/L (n=34), 23.59+/-27.74 microg/L (n=19) and 12.72+/-10.72 microg/L (n=22) respectively. This indicated that among environmental water sources, the ditch iodine content was the highest with river water iodine being the lowest (P<0.01). (3) Soil iodine value was 0.11-2.93 mg/kg (mean of 1.32 mg/kg). Though there was no statistical difference of soil iodine in different districts (P=0.131), soil iodine content correlated positively with water iodine content.

CONCLUSIONIodine concentration in salt accords with national policy of adding iodine in salt. Foreland has more iodine in water than mountain area. The data reflected that water and soil iodine in foreland area was not high, which suggests universal iodized salt should be necessary. Environment iodine has relatively close association with pollution.

China ; Iodine ; analysis ; Rivers ; chemistry ; Sodium Chloride ; analysis ; Sodium Chloride, Dietary ; analysis ; Soil ; analysis ; Water ; analysis ; Water Supply ; analysis

OBJECTIVE: This study assesses the impact of iodine-rich processed foods and dining places on the iodine nutritional status of children. METHODS: School-aged children (SAC) in seven provinces in China were selected by school-based multi-stage sampling. Urinary iodine, salt iodine, and thyroid volume (TVOL) were determined. Questionnaires were used to investigate dining places and iodine-rich processed foods. The water iodine was from the 2017 national survey. Multi-factor regression analysis was used to find correlations between variables. RESULTS: Children ate 78.7% of their meals at home, 15.1% at school canteens, and 6.1% at other places. The percentage of daily iodine intake from water, iodized salt, iodine-rich processed foods, and cooked food were 1.0%, 79.2%, 1.5%, and 18.4%, respectively. The salt iodine was correlated with the urinary iodine and TVOL, respectively (r = 0.999 and -0.997, P < 0.05). The iodine intake in processed foods was weakly correlated with the TVOL (r = 0.080, P < 0.01). Non-iodized salt used in processed foods or diets when eating out had less effect on children's iodine nutrition status. CONCLUSION Iodized salt remains the primary source of daily iodine intake of SAC, and processed food has less effect on iodine nutrition. Therefore, for children, iodized salt should be a compulsory supplement in their routine diet.
Humans ; Child ; Nutritional Status ; Cross-Sectional Studies ; Iodine ; Sodium Chloride, Dietary/analysis* ; China ; Water

OBJECTIVE: To recognize the spatial and temporal characteristics of iodine deficiency disorders (IDD), China national IDD surveillance data for the years of 1995-2018 were analyzed. METHODS: Time series analysis was used to describe and predict the IDD related indicators, and spatial analysis was used to analyze the spatial distribution of salt iodine levels. RESULTS: In China, the median urinary iodine concentration increased in 1995-1997, then decreased to adequate levels, and are expected to remain appropriate in 2019-2022. The goiter rate continually decreased and is expected to be maintained at a low level. Since 2002, the coverage rates of iodized salt and the consumption rates of qualified iodized salt (the percentage of qualified iodized salt in all tested salt) increased and began to decline in 2012; they are expected to continue to decrease. Spatial epidemiological analysis indicated a positive spatial correlation in 2016-2018 and revealed feature regarding the spatial distribution of salt related indicators in coastal areas and areas near iodine-excess areas. CONCLUSIONS Iodine nutrition in China showed gradual improvements. However, a recent decline has been observed in some areas following changes in the iodized salt supply in China. In the future, more regulations regarding salt management should be issued to strengthen IDD control and prevention measures, and avoid the recurrence of IDD.
China/epidemiology* ; Iodine ; Prevalence ; Sodium Chloride, Dietary ; Spatial Analysis ; Time Factors

OBJECTIVETo assess the level of dietary iodine intake and its contribution in Zhejiang.

METHODSA total of 9798 subjects were recruited in this survey with multi-stage stratified cluster random sampling method in April, 2010, the 24-hours dietary recall method and the "food composition table" were used to obtain the dietary iodine intake, and edible salt and drinking water samples were collected to detect the content of iodine.

RESULTSA total of 9798 subjects were included in this survey. The mean intake of dietary iodine in Zhejiang residents per standard man-days was (395.13 ± 78.16) µg/d, which in between of Recommended Nutrient Intake (RNI) 150 µg/d and Tolerable Upper Intake Level (UL) 1000 µg/d; the iodine intake of 18.40% (1803/9798) subjects was lower than estimated average requirement of iodine (EAR), 4.68% (459/9798) subjects was higher than the UL. The means of dietary iodine intake in various areas were (498.85 ± 96.77) µg/d, (384.50 ± 88.76) µg/d and (326.33 ± 78.32)µg/d in inland areas, sub-coastal areas and coastal areas, successively (F = 27.17, P < 0.05); the proportions of dietary iodine intake lower than EAR were 34.89% (1239/3551), 10.48% (370/3530) and 7.14% (197/2717) in coastal areas, sub-coastal area and inland areas, successively (χ(2) = 62.87, P < 0.01) , while those higher than UL were 5.10% (180/3530), 4.86% (132/2717) and 4.14% (147/3551) in sub-coastal area, inland areas and coastal areas.In the condition of ignoring cooking loss, the mean contribution of dietary iodine intake in edible salt, all kinds of food and drinking water were 74.92% (296.03/395.13), 23.85% (94.24/395.13) and 1.23% (4.86/395.13), successively; the contributions of edible salt in inland areas, sub-coastal areas and coastal areas were 83.72% (417.64/498.85), 73.05% (280.88/384.50) and 66.83% (280.09/326.33), successively; the contributions of drinking water in sub-coastal areas, coastal areas and inland areas were 1.61% (6.19/384.50) , 1.44% (4.70/326.33) and 0.65% (3.24/498.85) , successively (χ(2) = 7.24, P = 0.032) ; the contribution of laver in coastal areas, sub-coastal areas and inland areas were 22.57% (73.65/326.33), 17.11% (65.79/384.50) and 8.09% (40.36/498.85), successively (χ(2) = 82.17, P < 0.01) ; the contribution of sea fish in coastal areas, sub-coastal areas and inland areas were 2.38% (7.77/326.33), 0.72% (2.77/384.50) and 0.68% (3.39/498.85) (χ(2) = 19.47, P = 0.012).

CONCLUSIONSThe dietary iodine intake of Zhejiang residents was at recommended intake levels; the iodized salt turns out to be the main source, the iodine nutrition level was relatively low in coastal areas of Zhejiang, which the coverage of iodized salt should be improved.

China ; Diet Surveys ; Drinking Water ; Female ; Humans ; Iodine ; analysis ; Male ; Nutritional Status ; Rural Population ; Sodium Chloride, Dietary ; analysis ; Urban Population

OBJECTIVEIn order to understand the iodine nutritional status, after the salt-iodine content was showed a reduction in 2012 and to evaluate the current situation after the new standards was brought into force to the general population in an experimental community of Yunnan province.

METHODSRandomly sampled urine and salt were collected, to test the iodine concentration in the study-site. Pre-and post-levels of the iodized salt under the provision of the new standards, were identified.

RESULTSof this study were gathered upon 3 weeks or 3 months, respectively. Results Data from the three randomly chosen study sites showed that the urine iodine concentration in the general populations was reducing gradually. In the general population, medians of Urine Iodine (MUI) were 279.71 µg/L, 239.64 µg/L and 226.26 µg/L, respectively. Proportion of the urine iodine value for 100-199 µg/L increased but ≥300 µg/L decreased, after the new standard was put into practice. Both homogeneity and stability of the new standard on iodized salt seemed to be good.

CONCLUSIONIodine nutrition in general population appeared reasonable under the use of newly set salt-iodine standards in general population living in Yunnan province.

China ; Humans ; Iodine ; administration & dosage ; analysis ; urine ; Nutrition Policy ; Nutritional Status ; Sodium Chloride, Dietary ; administration & dosage ; analysis

OBJECTIVETo assess the effect of different levels of salt iodine content on thyroid volume (ThV) distribution using data from the 1999, 2011, and 2014 Chinese national iodine deficiency disorder (IDD) surveys.

METHODSProbability proportion to size (PPS) sampling method was used to obtain a representative national sample of 34,547, 38,932, and 47,188 Chinese children aged 8-10 years in 1999, 2011, and 2014 Chinese national IDD surveys, respectively. The iodine content in household iodized salt and urinary iodine concentration were measured and thyroid ultrasound examination was performed. The data were analyzed by SAS software using histograms and box plots. The skewness and kurtosis were calculated for testing the normality of ThV.

RESULTSThe median iodine content in household iodized salt dropped from 42.30 mg/kg in 1999 to 25.00 mg/kg in 2014. The median urinary iodine concentration of children aged 8-10 years decreased from 306.0 μg/L in 1999 to 197.9 μg/L in 2014. The median and interquartile range (IQR) of ThV in 1999, 2011, and 2014 surveys were 3.44 mL and 1.50 mL, 2.60 mL and 1.37 mL, 2.63 mL and 1.25 mL, respectively. The skewness and kurtosis of ThV distribution in 1999, 2011, and 2014 surveys were 1.34 and 5.84, 0.98 and 3.54, 1.27 and 5.49, respectively.

CONCLUSIONWith reduced salt iodization levels, the median urinary iodine concentration and median ThV of children decreased significantly, and the symmetry of the ThV distribution improved.

Child ; China ; Female ; Humans ; Iodine ; analysis ; deficiency ; Male ; Nutritional Status ; Sodium Chloride, Dietary ; analysis ; Thyroid Gland ; diagnostic imaging ; Ultrasonography

OBJECTIVETo evaluate the iodine nutrition level of population in Zhejiang province and to analyze the relevant influencing factors from 2009 to 2011.

METHODSFrom 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.

RESULTSThe 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.

CONCLUSIONIodine 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.

Adolescent ; Adult ; Aged ; China ; epidemiology ; Cross-Sectional Studies ; Drinking Water ; analysis ; Female ; Goiter, Endemic ; epidemiology ; Humans ; Iodine ; analysis ; urine ; Male ; Middle Aged ; Pregnancy ; Sodium Chloride, Dietary ; analysis ; urine ; Young Adult

BACKGROUND: Before iodination of Swedish table salt in 1936, iodine deficiency resulting in goitre and hypothyroidism was common. Sweden has become iodine sufficient, as shown in a national survey in 2007, proving its iodination fortification programme effective for the general population. The objective of this study was to collect drinking water from water treatment plants nationally and test if water iodine concentration (WIC) correlated to urinary iodine concentration (UIC) of school-aged children in a national survey 2007 to former goitre frequency in 1929 and to thyroid volume data in 2007. METHODS: In 2012, 166 treatment plants, located in 57% (166 of 290) of all Swedish municipalities, were asked to collect drinking water samples of approximately 10 ml. In 2007, tap water samples of the same volume were collected from 30 randomly selected schools for the national survey. Analysis of WIC was done in both treatment plants in 2012 (n = 166) and tap water in 2007 (n = 30). The correlation of WIC to the children's UIC and thyroid volume after iodination was tested based on data from the national survey in 2007. The association of WIC to former goitre frequency was tested based on pre-iodination data, derived from a map of goitre frequency drawn in 1929. RESULTS: The median WIC from water treatment plants was 4.0 μg/L (range 0-27 μg/L). WIC was similar in coastal and inland areas, for both ground and surface water. WIC correlated with historical goitre areas and was lower in the goitre areas than in non-goitre areas (p < 0.001). WIC in the same municipalities as the schools correlated with the UIC of children (p < 0.01), but not with their thyroid volume. CONCLUSIONS WIC still contributes to iodine nutrition in Sweden, but iodination overrides the goitre effect.
Adolescent ; Child ; Drinking Water ; chemistry ; Female ; Food, Fortified ; analysis ; Goiter ; epidemiology ; history ; History, 20th Century ; History, 21st Century ; Humans ; Iodine ; analysis ; urine ; Male ; Sodium Chloride, Dietary ; analysis ; Sweden ; epidemiology ; Thyroid Gland ; anatomy & histology