ABSTRACT
To determine and develop rapid on-site testing of iodine in salt and water samples and its use as field methods for monitoring and evaluation of the Iodine Deficiency Disorders (IDD) program. Methods: In order to monitor iodine in salt, the single bottle technique is recommended, utilizing SHMP (May & Baker), tapioca flour, KI and sodium azide. Secondly, to monitor iodine in water, the double bottle technique is employed and this utilizes 3N HCl as a substitute for SHMP to acidify flour, KI and sodium azide. Results: In salt, it is not positive until the colour starts to change from brown to black. In water, when it is positive reaching beyond an optimum level at 100-200 mg of iodine per litre, the colour starts to appear as faint blue and becomes darker blue as concentration of iodine increased. Discussion: Statistically, Spearman rank correlation co-efficient and the prediction method showed approximation of the two methods in estimation of iodine levels, indicating the interchangeability of the eyesight and it can be used in screening in place of the spectrophotometer. Conclusion: These techniques are cheap, simple and effective. This allows the monitoring kit to be beneficial and easy to use. These methods are ordinary and natural, and thus, in harmory with Thai culture and customs.
ABSTRACT
The use of drinking water as an additional vehicle for iodine to common salt has its origins in the fact that a low and irregular intake of common salt has led to a high prevalence of goitre in the north of Thailand. The distribution of salt in the north is poor. Culturally water is offered to passers-by and guests in every house. Thus, iodized salt and iodized water are combined to increase the efficacy of both, for children in primary schools in a village in Nan province where goitre is prevalent. At the end of 12 months of a strictly controlled study in 172 placebo and 114 treated subjects, the prevalence in the treated group was reduced dramatically from 60.2 to 10.5%. The urine and serum findings in the post-test samples became normal when compared with those of the pre-test samples. Both iodized salt and iodized water have been used to help relieve iodine deficiency to date. No complications were found in this series of volunteers. Monitoring and evaluation of the method showed that, if the daily dose of iodized salt was consistently 50ppm and that of iodized water 100mg per litre, this can be continued indefinitely until all areas of the country are fully developed. In conclusion, using combined iodized products under close supervision is definitely more effective than using iodized salt or iodized water alone.