宁夏平罗县居民最适宜食盐加碘量的研究

Investigation of the Optimal Concentration of Iodine Added to Dietary Edible Salt in Pingluo of Ningxia

目的研究宁夏平罗县居民最适宜的食盐加碘量,为宁夏局部调整盐碘水平提供依据。方法在平罗县下辖的灵沙村和西灵村中,按照随机抽样的原则,调查8～10岁学生170名,成人(18岁～)100名、孕妇+乳母22名,共计292名。采集调查对象日间一次随机尿样,用过硫酸铵消化砷铈催化分光光度法测定;用三日称量法计算每人每日食盐食用量,同时采集居民食用盐,用直接滴定法测定碘盐含碘量;以世界卫生组织等推荐的孕妇和乳母的碘摄人量为基准推算最适宜的食盐加碘量。结果上述3组人群的尿碘中位数为237.9μg.L-1,推算的碘摄入量为295.6μg.d-1,食盐食用量平均为10.7g.d-1,食盐碘含量平均为32.5 mg.kg-1,碘盐供给的碘量为226.0μg.d-1;环境来源碘为69.6μg.d-1。结论宁夏平罗县农村居民最适宜的食盐加碘量为(17.0～31.6)mg.kg-1,现行国家标准(20～50)mg.kg-1尚有下调的空间。

Objective To investigate the optimal concentration of iodine added to dietary edible salt in Pingluo county and to provide scientific evidence for Ningxia adjustment on edible salt concentration in local areas.Methods Targeted subjects were chosen from lingsha and xiling village in Pingluo county and were divided into three groups： age 8～10 students,age 18 or above,pregnant or lactating women.Their urinary iodine excretion levels were examined by ammounium persulfate digestion-arsenic ce catalytic spectrophotometry.Their daily edible salt intake was recorded and the iodine concentration in the edible salt was measured by direct titration.Results The medium of the urinary iodine concentration of the four groups was 237.9 Iμg·L-1,and from which the mean iodine intake was calculated to be 295.6 μg·d-1.The average amount of edible salt intake was 10.7 g·d-1.The current iodine concentration in the edible salt was 32.5 mg·kg-1,out of which 226.0 μg·d-1 of iodine was excreted from urine daily.Therefore,iodine obtained from the living environment other than salt was 69.6 μg·d-1.Conclusion The recommanded optimal iodine concentration added to the edible salt for Pingluo county is（17.0-31.6）mg·kg-1.The current national standard（35±15）mg·kg-1 could be adjusted lower.