Control of iodine deficiency using iodination of water in a goitre endemic area

Salt iodination is the method of choice for prevention of iodine deficiency in most parts of the world. However, establishment of such a program frequently involves considerable changes in the marketing and distribution patterns and requires years to achieve. This study was conducted to evaluate the efficiency of using well-defined water sources containing iodine-saturated silicon matrices for providing adequate iodine supply to an iodine deficient population in Kordofan State, Western Sudan. A system of water iodination using silicon matrices containing 30% sodium iodide placed in polyethylene baskets was used in four villages using either traditional wells or hand pumps. Before and every 6 months after iodination of water, urine and blood samples were obtained for determination of iodine and thyroid-related hormones, respectively. Goitre assessment on the village populations were performed at the start and 2 years later. Improvements in iodine status were recorded in all the study villages. The water iodine concentrations increased and a higher iodine content was observed in the hand pumps compared to the traditional wells. The median urinary iodine concentrations increased significantly, from 0.19, 0.20, 0.19, 0.11 to 1.20, 1.10, 0.37, 0.30 mumol/l in the four villages, respectively. The percentages of subjects with serum TSH above 4 mU/l were decreased from more than 30% before iodination to less than 15% at 2 years after iodine supply and the mean serum thyroxine hormone values rose. The rates of goitre decreased from 69% to less than 25%. The study shows that this system is effective, cheap, safe and practically applicable under conditions prevailing in rural areas in developing countries with iodine deficiency.