Unsatisfactory results of the Tunisian universal salt iodization program on national iodine levels

Lack of iodine intake may promote a spectrum of disorders termed iodine deficiency disorders. Universal salt iodization laws were adopted in Tunisia to overcome this problem. This study examines the adequacy of iodized salt in the distribution chain two decades after its last assessment. A cross-sectional design was carried out in 2012 using the multi-stage cluster sampling technique. Salt samples from 24 governorates were collected at wholesaler level (n = 635), retailer level (n = 1440) and household level (n = 1560), and analyzed using a validated iodometric titration method. Iodine concentration at each level of distribution chain was within the recommended range of 15-27 mg/kg. Iodine content in household salt was significantly different according to the salt manufacturer and also between geographical regions (p < 0.0001). Moreover, an insufficient coverage of adequately iodized salt consumption (less than 90%) was found with reference to international standards (≥15 mg/kg). About 85.6% (95%CI: 78.3-90.8) of analyzed samples were adequately iodized at the intermediate levels of supply-chain (wholesalers and retailers). Our study demonstrates a decrease in the availability of iodized salt in households. It can thus be concluded that universal salt iodization legislation has not been sufficient to ensure an adequate supply of iodine in the population, and an evaluation system needs to be reactivated.