Geochemistry and bioavailability of iodine in water and soil in Dehdasht, Kohgiluyeh and Boyerahmad province

Iodine is an essential micronutrient for human health, hence iodine deficiency causes various damages such as thyroid disorders. Climate and geological settings are the causes of the incidence and prevalence of the mentioned disorder. A bibliographic survey showed that no studies have been undertaken so far in this area with regard to geological setting, so in this research we focused on geological reason(s) with investigation on soil and water. In response to reports on the high incidence of iodine disorders in Dehdasht area, 16 ground water samples were taken from agricultural wells, drinking water and springs in the area to analyze anions, cations and iodine. The results showed that iodine levels were high in some water samples. To study the effect of soil on iodine, 20 soil samples were taken from various formations and pH, iodine as well as organic matter were measured. iodine can exist in several species. In different environments, the mobility of iodine depends on the type of iodine.The results showed that due to the presence of calcareous formations, high pH and calcium can lead to low mobility of iodine Also the alkaline and reduction conditions, can cause high mobility and enrichment of iodine in groundwater.