黄河三角洲水源性高碘地区分布与居民食用盐现状调查研究

目的查清黄河三角洲的水源性高碘地区分布和居民食用盐现状以制定干预策略。方法采用横断面调查方法,每个被调查县的所有乡镇均按东、西、南、北、中五个不同方位抽取5个村,在每个村采集饮用水样2份进行水碘含量检测,并了解饮水源类型及水井深度。每个村随机采集5个户居民食用盐进行定性检测。结果调查8个县92个乡镇的451个村庄,检测水样800份、食盐800份。水碘含量均值为(110.93±152.26)μgL,中位数为55.83μgL(0.84～997.82μgL);96.5%为平原地区水源。井深平均(70.44±136.19)m,中位数12.0m(2.0～999.0m)。水碘>150μgL的高碘地区,分布于7个县的24个乡镇,受累人口102.39万人,碘盐覆盖率97.2%;其水碘含量为(327.72±192.19)μgL,中位数253.87μgL(150.78～997.82μgL)。浅层井水的高碘含量可能与黄河泛滥把从上游携带来的富碘泥沙的长期沉积有关,而深井水高碘成因除此之外还与三角洲的沉积及海底大陆架千万年来沉积的富碘海洋生物有关。结论黄河三角洲有24个高碘地区,碘盐覆盖率97.2%,既有浅井高碘水又有深井高碘水的独特现象。高碘地区应停止碘盐供应措施,开展健康教育和监测工作。

Study on the present status of the areas with high iodine concentration in drinking water and edible salt at household levels in Ohio of Yellow River

OBJECTIVE: To understand the present condition of iodine excess areas and edible salt at household levels in Ohio of Yellow River,which will provide the evidence to control it. METHODS: A cross section in one time was adopted for the epidemiological survey based on the east, west, south, north and central in all of townships from 8 counties. 2 samples of drinking water from each village were tested their water iodine content as well as the data regarding to their recourses and the depth of wells. 5 samples of edible salt were collected from each village for quantitative analysis. RESULTS: We investigated 451 villages in 92 townships of 8 counties. 800 samples of drinking water were tested which values of iodine content were (110.93 +/- 152.26) microg/L in main, 55.83 microg/L (0.84 - 997.82 microg/L) in medium. 102.39 thousand population are at risk for iodine excess and living in 24 townships of 7 counties where iodine concentration is over 150 microg/L in drinking water, with (327.72 +/- 192.19) microg/L in mean value or 253.87 microg/L (150.78 - 997.82 microg/L) in medium. The rate of iodized salt is 97.2%. All the iodine excess areas are located in alluvial plain of Yellow River. The etiology of high iodine in shallow well water may be supposed to be iodine aggregation formed by Yellow River in terms of thousands of flood in thousands of years. But iodine excess in deep well water may be related to rotten, deposit marine living beings rich in iodine millions upon millions years ago. CONCLUSION: There were distinctive features of iodine excess in drinking water from both shallow well and deep well, 24 iodine excess areas in Ohio of Yellow River. It has suggested that iodized salt intervention should be stopped in the areas and starting the health education project, survey of iodized salt in the region.