Objective   To understand the function of the content of water iodine to the iodine nutrition level in different population in Shenzhen.

  Methods   To collect punctately the urine, drinking water and salt among children aged 8-10 living continually in the city for over three years and women of early pregnant, middle pregnant and lactation, to test the iodine content.

  Results   The median(M)of water iodine of the 211 cases in suburb and 325 cases in urban were 3.2 μg/L(0.515.44 μg/L)and 23.6 μg/L(6.80-42.58 μg/L)respectively, the value of M of salt iodine were all close to 32 mg/kg; 6.7% children in rural was with the urine iodine 15.0% in urban, the urine iodine of early and middle pregnant women in urban was lower than 100 μg/L, which occupied 14.6% and 2.7% respectively, and those of the non-pregnant women and lactation were all lower than 6.0%;Children aged from 8 to 10 whose iodine was over the normal range occupied 65.5% in urban, and those of the non-pregnant and lactation occupied 54.1% and 80.0% respectively.

  Conclusion   The very low content of water iodine could cause the direct influence on the iodine nutrition lack in suburb, and the water iodine in urban had the obvious restraining effect on the iodine lack of the pregnant women, but had the cooperate effect on the iodine nutrition surplus of the other poplation.The way of salt added with iodine was not fit to be implemented in Shenzhen any more.