随着食盐加碘政策实施成功地控制了碘缺乏病，人们开始重视碘过量对健康的危害，食盐加碘的安全性也引起社会关注。确定碘可耐受最高摄入量(tolerable upper intake level, UL)是防止碘过量摄入、坚持科学补碘的关键，亦是当前亟待解决的公共卫生问题。经过前期调查和实验，我们已成功制定成人碘安全摄入量，同时在儿童的流行病学调查中发现，目前我国规定的儿童碘安全上限值800μg/d过高，亟需开展研究制定适合我国儿童的碘UL。因此，本课题组拟对高水碘地区常住儿童进行横断面调查，采用24h尿碘精确评定不同水碘暴露下儿童碘摄入量，并对儿童的TSH、T3、T4、TPOAb、TGAb等与碘过量相关的敏感指标进行检测，明确我国儿童的碘安全摄入水平，探讨长期高碘暴露对儿童健康的影响。研究结果将为修订人群碘膳食参考摄入量(DRIs)提供依据，对高碘危害的防治及食盐补碘科学长久地实施具有重要意义。

Iodine deficiency diseases have been successfully controlled since the implementation of salt iodization, however more and more attention was drown to the hazard caused by excessive iodine intake, and the safety of salt iodization has become the public concern issue. Confirming the tolerable upper intake level of iodine for different population is the key of preventing excessive iodine intake and scientifically persisting in iodine supplementation, which is also the current public health problem need to urgently solved. With early investigation and human experiment, we have successfully established the tolerable upper safe level of iodine for adult, simultaneously we found the upper safe level of iodine of 800μg/d for children was pretty high during the epidemiological study in children, which need to be further studied. Thus, our group will carry out a cross-sectional study on children who live in high water iodine areas, adopting 24h-urinary iodine to precisely evaluate iodine intake of children exposed to different levels of water iodine, and detecting TSH、T3 、T4 、 TPOAb、TGAb to identify the upper safe level of iodine for children in our country and explore the effects on health of children with long-term high iodine exposure. The results of this study will provide data for revising Chinese DRIs and will be meaningful for preventing excessive iodine intake and assuring the sustained and proper implementation of salt iodization in future.