Quality Evaluation of Comercial Salt Samples

Abstract

Iodine is an essential micronutrient in the production of thyroid hormones, thyroxine and triiodothyronine. The regular consumption of iodine is a common strategy to avoid iodine deficiency problems. The commercial salt is consumed regularly, making it the ideal vehicle for the iodine consumption. In the 70s, Brazil adopted the salt iodations as a strategy to reduce the prevalence of endemic goiter and cretinism removal. This research describes the quality evaluation of six commercial samples of salt. The Mohr’s method, the metric complex with EDTA iodine metric analysis were used to determine the purity of NaCl, the content of iodine and the limit of calcium (as an impurity), respectively. In addition, a semi quantitative method, using a strip of filter paper impregnated with iodized starch gum, was proposed for the detection of iodine in salt. The results showed four samples containing iodine above the allowed quantity (20 - 60 mg/kg). None of the samples showed the required purity (over 99%). The semi quantitative method allowed the quick detection of the iodine presence in salt samples.