[Field study on the change of urinary iodine levels among family members with iodine content of 5 - 150 microg/L in drinking water before and after non-iodized salt intervention].
OBJECTIVE
To compare the changes of urinary iodine levels among the family members with iodine content of 5 - 150 microg/L in drinking water, before and after non-iodized salt intervention through a field trail study.


METHODS
Family members who routinely drank water with iodine content 5 - 150 microg/L were chosen to substitute non-iodized salt for their current iodized salt for 2 months, and urine samples of the family members were collected for determination of iodine change before and after intervention was carried out.


RESULTS
Median urinary iodine of school children, women with productive age and male adults exceeding 370 microg/L before intervention and the frequency distribution of urinary iodine were all above 70%. Our results revealed that iodine excess exited in three groups of family members. After intervention, all median urinary iodine level seemed to have decreased significantly, and groups with drinking water iodine 5.0 - 99.9 microg/L reduced to adequate or close to adequate while the group that drinking water iodine was 100 - 150 microg/L reached the cut-off point of excessive iodine level (300 microg/L).


CONCLUSIONS
Results from your study posed the idea that the iodine adequate areas should be defined as the areas with iodine content of 5.0 - 100 microg/L in drinking water, and edible salt not be iodized in these areas. Areas with iodine content of 100 - 150 microg/L in drinking water should be classified as iodine excessive.
Li
Su-mei
SM
National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China.
Zhang
Gen-hong
GH
Sun
Fan
F
Wang
Pei-hua
PH
Zhang
Zhi-zhong
ZZ
Li
Xiu-wei
XW
Li
Shu-hua
SH
D000293:Adolescent; D000328:Adult; D002648:Child; D005260:Female; D006801:Humans; D007454:Iodides / Q000652:urine*; D007455:Iodine / Q000652:urine*; D008297:Male; D008875:Middle Aged; D017673:Sodium Chloride, Dietary / Q000652:urine*; D014881:Water Supply; D055815:Young Adult
D007454:Iodides; D017673:Sodium Chloride, Dietary; C034024:iodized salt; D007455:Iodine