Objective:To monitor iodized salt consumption and evaluate iodine deficiency status in 2014 in China.Materials and Methods:In 2014,a nationwide cross-sectional survey was conducted in 31 provinces (in this study,provinces,autonomous regions and municipalities in Mainland China were named as provinces).Probability proportional to size sampling method was adopted to recruit children ages 8-10 and pregnant women.47,467 children's and 18,994 pregnant women's urine samples were collected and 47,706 children's thyroid volumes were examined.Iodine content in salt was determined with 46,900 edible salt samples from children's households;urinary iodine concentration (UIC) was tested from children and pregnant women's urine samples;thyroid volume of children was assessed by ultrasound.Results:The national coverage rate of iodized salt and consumption rate of qualified iodized salt were 96.3％ and 91.5％,respectively.Median iodine content in iodized salt was 25.2 mg/kg.In 22 of 31 provinces,the provincial coverage rates of iodized salt were over 95％.And consumption rates of qualified iodized salt were more than 90％ in 21 provinces.In this study,the national median urinary iodine concentration (MUIC) of children in China was 197.9 μg/L.At the provincial level,MUIC of children in 19 provinces was 100-199 μg/L,which in 12 provinces was 200-299 μg/L.The national MUIC of pregnant women in 2014 was 154.6 μg/L,slightly higher than the lower limit of the WHO criteria for adequate (150-249 μg/L).At the provincial level,MUIC of pregnant women in 18 provinces was 100-149 μg/L,which in 13 provinces was 150-249 μg/L.The national prevalence of goiter among children in 2014 was 2.6％,of which only Shandong province (5.6％) exceeded the national standard (5％).Conclusions:In China,iodine deficiency disorders (IDD) has been eliminated since 2005.And in 2014,the IDD-free status still remained.

Objective To understand the stability of iodine content in potassium iodide iodized salt and potassium iodate iodized salt during production.Methods The sodium sulfate type brine well rock salt and calcium salt brine well rock salt as raw material were used to produce potassium iodide salt and potassium iodate salt by different iodization methods of before and after fluid bed dryer and then the loss of iodine during production was measured,meanwhile iodine content of powder salt was determined.According to the "Belt Delivery Sampling of Sampling Methods of the Main Products in the Salt Industry" (GB/T 8616-2001),25 standard salt samples and 6-24 powder salt samples were collected in the same batch.The salt iodine content was determined by oxidationreduction titration and direct titration of the "General Test Method in Salt Industry-Determination of Iodine" (GB/T 13025.7-2012).Results For the sodium sulfate type brine well rock salt,there was no statistical difference in iodine loss rate between potassium iodide salt and potassium iodate salt (16.55％ vs.19.60％,x2 =0.01,P ＞ 0.05) by iodization of before fluid bed dryer.The iodine loss rate of potassium iodide salt was 2.17％ and the iodine loss of potassium iodate salt was undetectable and there was no statistical difference between the two (x2 =2.19,P ＞ 0.05)by iodization of after fluid bed dryer.For calcium salt brine well rock salt,the iodine loss rate of potassium iodide was less than that of potassium iodate (20.60％ vs.39.75％,x2 =8.70,P ＜ 0.05) by iodization of before fluid bed dryer and neither of them was lost by iodization of after fluid bed dryer.Conclusions For both sodium sulfate type brine well rock salt and calcium salt brine well rock salt,the iodine loss of iodide iodized salt is not higher than that of potassium iodate during iodization of before or after fluid bed dryer.Since the iodine loss during iodization of before fluid bed dryer is significantly higher than that after fluid bed dryer,adopting iodization of after fluid bed dryer to produce iodized salt should be recommended.