Evaluation of iodide deficiency in Togo using an optimized potentiometric method for iodide estimation in urine

A pilot study was carried out in two Togolese localities (Gobe, Moretan) situated in an endemic goiter area. The aim of this work was to collect laboratory and nutritional data to assess and follow up campaigns against iodide deficiency. Ninety-seven urine samples were analysed. We studied the urinary excretion and the iodine concentration of important diet substances (water and salt) using an optimized potentiometric method. Mean values of urinary iodide/creatinine ratios (microgram/g) observed in the two Togolese localities were respectively 34.1 +/- 6.3 in Gobe and 39.2 +/- 6.4 in Moretan. These low values differ significantly (P < 10(-9)) from the physiological values determined in Amiens, France (147.5 +/- 56.3). The drinking water of the two localities showed a low iodide concentration (2 micrograms/l). The iodide concentration of cooking salts was also low (< 0.2 mg/kg) compared with iodized salt used in France (11.2 +/- 0.2 mg/kg) These results show an iodide deficiency in both localities, probably due to the lack of iodide in the local diet. Iodide determination is specific, easy and inexpensive. It can be proposed for use in campaigns against goiters of nutritional origin.