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Background & Objective: Iodine deficiency is one of the most important life-threatening factors from the beginning and encounter irreversible damage to human. This study aimed to investigate stability of Iodine in iodized salt in different situations such as light and humidity and comparing it with standard amounts.
Methods: In this cross-sectional descriptive-analytical study, 12 samples of iodized salts which have been distributed in Damghan, were accidentally selected. Samples were examined in the chemistry laboratory of Faculty of Health (Damghan University of Medical Sciences) using titration method recommended by British pharmacopeh. 10 mg of each iodized salts were kept at presence of light, darkness, humidity, and non- humidity situation and then titration method was performed. The samples were kept for two weeks and examined weekly. Data were analyzed with T paired and ANOVA tests using SPSS software.
Results: Findings of this study showed that reduction of Iodine was seen for all samples. The amount of reduction were 2.2, 1.5, 4.1 and 2.1 mg/l for purified salts at light, darkness, humidity, and non- humidity situation, respectively. The amount of reduction were 3.4, 2.1, 5.35 and 2.6 mg/l for non-purified salts at light, darkness, humidity, and non- humidity situation, respectively. In spite of reduction in Iodine, concentration of it was at standard amount (30-50 PPM).
Conclusion: Results showed that stability of iodine was more when salt was exposed to darkness in comparison with light situation (p< 0.09). Meanwhile, the stability of purified salts was more than the non- purified salts (p< 0.28). Also, stability of iodine was less at humidity in comparison with non- humid situation (p< 0.006). The purified salts which was exposed to humidity was much stable compared to the non- purified salts (p< 0.28). It also, demonstrated that the amount of iodine stability was more for salts which was exposed to light in comparison with humidity (p< 0.05).