Monitoring data analysis of iodized salt of national key sample in China in 2008 / 中国地方病学杂志

ABSTRACT

Objective To understand the current level of iodized salt coverage in areas with intensified monitoring measure in China in 2008. Methods In accordance with the "National Iodine Deficiency Disorders Surveillance Program (Trial)" of Ministry of Health issued in 2007, the selected key counties (cities, districts and banner) were divided into 5 sub-areas, 1 non-iodine townships(towns, street offices) was sampled randomly in each sub-area, 4 administrative villages (neighborhood committees) were sampled from each selected township;15households salt samples in each selected village were randomly collected. All salt samples were detected by semiquantitative kit at first. The salt samples that can not be determined by the kit were tested by direct titration and the arbitration act (GB/T 13025.7-1999) detection. Iodized salt determination criteria: reagent color change in semiquantitative test kit or iodine content ≥ 5 mg/kg were identified as iodized salt. Otherwise, the salt samples were identified as non-iodized salt. Results All the provinces(autonomous regions, municipalities) except Tibet in China had conducted a specific survey on iodized salt coverage in non-iodized salt high-risk areas, which revealed that the national coverage rate of iodized salt was 93.01%(130 928/140 770). At the provincial level, twenty provinces and the Xinjiang Production and Construction Corp had a iodized salt coverage over 90%, while the other six provinces (Beijing, Xinjiang, Zhejiang, Fujian, Tianjin and Jiangxi) between 80% - ＜ 90% and the rest four provinces,such as Guangxi, Qinghai, Guangdong and Hainan, lower than 80%. At the county level, 64.57%(277/429) of all the surveillance counties had a iodized salt coverage over 95% while 10.02%(43/429) lower than 80%. Among all the six types of areas where specific survey were conducted, areas with incomplete iodized salt distribution network and areas with crude salt production had a iodized salt coverage lower than 90%, 81.74%(4978/6090) and 86.53%(17 098/19 759), respectively. In raw salt production area, there were 10 out of 21 provinces with iodized salt coverage rate below 90%, it consisted of 47.6%(10/21) of the total monitoring provinces in the same type areas.There were 8 out of 16 provinces with iodized salt coverage rate lower than 90% in the areas with faultiness iodized salt network, it consisted of 50.0%(8/16) of the sampling provinces in the same type area. Conclusions Most provinces(21) in China have a relatively high iodized salt coverage at household level during this specific survey.Areas with incomplete iodized salt distribution network and crude salt production are the most affected areas by noniodized salt. Aiming at the high-risk non-iodized salt areas discovered during this survey, corresponding intervention measures should be implemented with joint efforts from sectors concerned.