Résumé
OBJECTIVE: To assess the iodine nutritional status of school children in selected areas of Imphal West District of Manipur where endemic goitre and associated iodine deficiency disorders (IDD) are prevalent in the post-salt iodization period. METHODS: A total of 961 school children in the age group 6-12 yrs of both sexes were clinically examined for goiter from three study areas- one from rural block and two from urban areas. One hundred twenty urine samples were analysed for iodine and thiocyanate respectively. One hundred and five edible salt samples were also collected from the households to evaluate the iodine content. Drinking water samples from different sources were collected and iodine level was analysed to study the bioavailability of iodine in the region. RESULTS: The total goiter rate was 34.96% (Grade 1- 32.15%; Grade 2- 2.81%) showing that IDD is a severe public health problem. The median urinary iodine levels in the studied areas were in the ranges from 12.5-17.5 microg/dl indicating no biochemical iodine deficiency in the region. Mean urinary thiocyanate level was 0.839+/-0.33 mg/dl showing that the people consume sufficient foods containing thiocyanate precursors. About 82% salt samples had iodine level more than 30 ppm and the iodine content in salt samples less than 15 ppm was only about 3% indicating the salt samples at house hold contain adequate iodine. CONCLUSION: Iodine content in drinking water samples ranged from 1.8-2.6 microg/l showing that the studied region is environmentally iodine deficient. Inspite of the consumption of adequate iodine, the existing goiter prevalence among school children during post salt iodization phase ensures that environmental factors other than iodine deficiency may have the possible role in the persistence of endemic goiter in the population. The role of thiocyanate in this regard may not be ruled out.