The evaluation of the iodine content of table salt in Lesotho

The objective of the study was to investigate the iodine content of salt at both retail and household levels before the introduction of the universal salt iodisation legislation in Lesotho. A cross sectional study was conducted. 300 salt samples were collected from systematically selected households and 100 salt samples were collected from retailers situated in the same villages as the households selected for this study, in all ten districts of Lesotho. An iodometric titration method was used for analyzing the iodine content of the salt samples. The mean iodine content of salt at both retail and household level of 37 ppm ranged from 29 ppm to 48 ppm and from 31 ppm to 45 ppm in the different districts at retail and household level respectively. Uniformity of iodisation was lacking as indicated by the large variation in the mean iodine content among brands (ranging from 1-46 ppm at household level and 1-53 ppm at retail level as well as within brands (ranging from 7-97 ppm at household level and 12-76 ppm at retail level). 4% of households used non iodised salt. 18.2% of the household salt samples were below the adequate iodisation level of 15 ppm. 81.8% of the households use adequately iodised salt. This however does not meet WHO criteria for elimination of IDD as a public health problem since less than 90% of effectively iodised salt is being used at household level.