Iodine in biology
The U.S. Institute of Medicine (IOM) updated Estimated Average Requirements (EARs) and Recommended Dietary Allowances (RDAs) for iodine in 2000. For people age 14 and up, the iodine RDA is 150 μg/day; the RDA for pregnant women is 220 μg/day and the RDA during lactation is 290 μg/day. For children 1–8 years, the RDA is 90 μg/day; for children 8–13 years, 130 μg/day. As a safety consideration, the IOM sets tolerable upper intake levels (ULs) for vitamins and minerals when evidence is sufficient. The UL for iodine for adults is 1,100 μg/day. This UL was assessed by analyzing the effect of supplementation on thyroid-stimulating hormone. Collectively, the EARs, RDAs, AIs and ULs are referred to as Dietary Reference Intakes (DRIs).
Tincture of iodine
Iodine solution is used to sanitize the surface of fruit and vegetables for bacteria and virus. The common concentration for sanitization is 25 ppm idophor for 1 minute. However, the effectiveness depends on whether the solution penetrates into rifts, and whether dirt is effectively removed at first. But, oocytes of protozoan parasites will not be killed, and it is also doubtful that bacterial spores are killed. Iodine solutions should not be considered able to sanitize or disinfect salad, fruit or vegetables that are contaminated by feces. Thus, it should not be considered safe to eat raw fruit, salads and vegetables which are sanitized with iodine, if they could be contaminated by feces.