Efficiency Evaluation of Iodized Salt Supply in Prevention of Iodine Deficiency Disease in Tianjin in 1995-2005

Objective To evaluate the efficiency of ten years of iodized salt supply in prevention and control of iodine deficiency disease (IDD) in Tianjin. Methods 1 200 pupils aged 8-10 years with 1:1 of sex ratio were chosen in the regions where iodized salt supply had been conducted for 10 years (1995-2005), the prevalence rate of goiter, the level of urine iodine and the iodized salt consumption were investigated. Results The prevalence rate of goiter of children aged 8-10 years in Tianjin decreased from 32.6% to 1.8% after 10 years of iodized salt supply, the median of urinary iodine increased from 96 μg/L to 228 μg/L. In the high water iodine regions, the prevalence rate of goiter was 8.1%, the median of urinary iodine was 576 μg/L. Conclusion 10 years of iodized salt supply can significantly prevent and control IDD in the regions where there is iodine deficiency in drinking water, but the problem should not be neglected that iodine excess in the regions where the concentration of iodine in drinking water is higher. Reasonable iodine supplement is the key to prevent and control IDD as a whole.