Guo Xiaowei, Qin Qiliang, Liu Chuanjiao, Zhai Liping
Shandong Institute for Endemic Disease Control and Research, Ji'nan 250014, China.
Wei Sheng Yan Jiu. 2007 Jul;36(4):427-31.
To investigate the iodine nutritional status of key population living areas with iodine excess in drinking water before and after stopped iodized salt supply to provide strategies of control excessive iodine.
The levels of iodine in drinking water, edible salt of household and urine of school-age children and child-beard age women were investigated at four villages A, B, C and D which iodine concentrations of 50-100, 100-150, 150-300 and more than 300microg/L. The results of iodine in water, edible salt, urine and thyroid goiter were observed before stopping iodized salt. The levels of urinary iodine in four groups were tested after stopped iodized salt one or two month later.
The medians of iodine concentration in inhabitants from four groups A, B, C and D were 93.20, 143.23, 194. 10 and 805.85microg/L of drinking water, in edible salt 25.38, 28.21, 30.01 and 32.87mg/kg. Goiter rate was 15.9%, 5.9%, 12.7% and 24.0%, respectively. The median of urinary iodine (MUI) was 384.60, 374.85, 439.90 and 1260.10microg/L. The proportion of urinary iodine level of 100-300microg/L was 32.3%, 28.3%, 13.6% and 1.0%, of more than 300microg/L was 67.7%, 70.8%, 86.4% and 99.0% with iodized salt supply. MUI of all groups with non-iodized salt decreased significantly after two month, especially in group A and B. The proportion of urinary iodine levels of 100-300microg/L was obviously more than before, but group more than 300microg/L was less than before. The similar changes of MUI were in children and women, but degree of change was obviously in group A. Their MUI were in normal after two month. There were significant difference in MUI of denizens including children and women before and after intervene. There was no difference of MUI in group C and D at the same time. There were significant correlations between urinary iodine and water iodine concentration (P < 0.001). MUI in group C, D was more than 300microg/L, but evident differences were found among 4 groups under different levels of water iodine (P < 0.001). The nutritious status of iodine was markedly excessive in group B, C and D of objects.
Iodine nutritional status in inhabitants drinking water iodine concentration about 90microg/L was in normal, iodized salt supply could be safely stopped at the regions. Regardless iodized or non-iodized salt supply, there was inefficient in those areas with water iodine much more than 100microg/L. It is suggested that iodized salt must be stopped for controlling excessive iodine in the areas.
调查饮用水碘过量地区重点人群在停供碘盐前后的碘营养状况，为控制碘过量提供策略。
在饮用水碘含量分别为50 - 100、100 - 150、150 - 300及大于300μg/L的A、B、C、D四个村庄，调查饮用水、家庭食用盐及学龄儿童和育龄妇女尿碘水平。观察停供碘盐前水碘、食用盐碘、尿碘及甲状腺肿大情况。停供碘盐1 - 2个月后检测四组人群尿碘水平。
A、B、C、D四组居民饮用水碘浓度中位数分别为93.20、143.23、194.10及805.85μg/L，食用盐碘分别为25.38、28.21、30.01及32.87mg/kg。甲状腺肿大率分别为15.9%、5.9%、12.7%及24.0%。尿碘中位数（MUI）分别为384.60、374.85、439.90及1260.10μg/L。碘盐供应时，尿碘水平在100 - 300μg/L的比例分别为32.3%、28.3%、13.6%及1.0%，大于300μg/L的比例分别为67.7%、70.8%、86.4%及99.0%。停供碘盐2个月后，各组MUI均显著下降，尤其是A组和B组。尿碘水平在100 - 300μg/L的比例明显高于停供前，大于300μg/L的比例低于停供前。儿童和妇女MUI变化趋势相似，但A组变化程度明显。2个月后其MUI均恢复正常。干预前后儿童和妇女等居民MUI差异有统计学意义。同时C组和D组MUI差异无统计学意义。尿碘与水碘浓度之间存在显著相关性（P < 0.001）。C组、D组MUI大于300μg/L，但不同水碘水平的4组间差异有统计学意义（P < 0.001）。B、C、D组对象碘营养状况明显过量。
饮用水碘浓度约90μg/L地区居民碘营养状况正常，该地区可安全停供碘盐。水碘远高于100μg/L的地区，无论供应碘盐与否，碘过量问题均未得到有效解决。建议该地区停供碘盐以控制碘过量。
