Study on the iodine nutrition and iodine deficiency disorders status in pasturing areas of Tibet-a non-epidemic area of iodine deficiency disorders in serious iodine deficiency district / 中华流行病学杂志

Objective To explore the status of iodine nutrition and iodine deficiency disorders in the pasturing areas and agricultural regions in Tibet. Methods 30 families were selected respectively in pastoral Dangxiong county and agricultural Qushui county of Lasa. Drinking water and edible salt were collected for testing the iodine contents. In each type of the following populations including children aged 8-10, women of child-bearing age and male adults, 50 subjects were randomly sampled to examine their urinary iodine contents. Among them, 50 children and 50 women were randomly selected for goiter examination by palpation. Results Water iodine content was less than 2μg/L, both in pasturing area and in agricultural areas. There was no iodized salt used in the families of pasturing areas, while 90% people consumed iodized salt in agricultural areas. The median of urinary iodine in pasturing area was 50.2 μg/L, significantly lower than that of agricultural area (193.2μg/L). However, the goiter rate of children and women in pasturing area was significantly lower than that in agricultural area. Conclusion Although iodine intake of populations in pasturing area of Tibet was severely deficient, there was no epidemic of Iodine Deficiency Disorders. This phenomenon noticed by the researchers deserved further investigation.

Surveillance on iodized salt in China, in 2006 / 中华流行病学杂志

<p><b>OBJECTIVE</b>To understand the national situation of quality and consumption of iodized salt at production and household levels.</p><p><b>METHODS</b>Detailed surveillance method could be found in 'national iodized salt surveillance scheme', issued by MOH in 2004. The iodine concentrations in salt (except some special kinds of salt) were detected by direct titration with national standard of GB/T 13025.7-1999, in which the iodine content in qualified iodized salt was set as between 20 and 50 mg/kg and that in non-iodized salt was set as below 5 mg/kg.</p><p><b>RESULTS</b>At production level, the national lot qualified rate was 98.36% and all the provincial lot qualified rate of production level was over 90%. At household level, the national iodized salt coverage rate of household was 96.87% and the national qualified iodized salt coverage rate was 93.75%. 4 provinces (Tibet, Hainan, Xinjiang and Guangdong) had an iodized salt coverage rate lower than 90%. Further, the qualified iodized salt coverage rate of 5 provinces (Tibet, Hainan, Xinjiang, Guangdong and Qinghai) was below 90%. In 2006,80 counties did not conduct the iodized salt surveillance and non-iodized salt coverage rate of 185 counties was higher than 10%. In the respect of the qualified iodized salt coverage rate at household level, there were about 10 percent lagging behind the national goal that 95% of all the counties in China should achieve virtual elimination of iodine deficiency disorder before 2010.</p><p><b>CONCLUSION</b>At national level,the lot qualified rate at production level and the iodized salt coverage rate at household level maintained comparatively well. However, at county level, there were 75 counties whose iodized salt coverage rate was below 70%.</p>