Unethical human experimentation in the United States
In 1953, the AEC ran several studies at the University of Iowa on the health effects of radioactive iodine in newborns and pregnant women. In one study, researchers gave pregnant women from of iodine-131, in order to study the women's aborted embryos in an attempt to discover at what stage, and to what extent, radioactive iodine crosses the placental barrier. In another study, they gave 25 newborn babies (who were under 36 hours old and weighed from ) iodine-131, either by oral administration or through an injection, so that they could measure the amount of iodine in their thyroid glands, as iodine would go to that gland.
Iodine
The simplest compound of iodine is hydrogen iodide, HI. It is a colourless gas that reacts with oxygen to give water and iodine. Although it is useful in iodination reactions in the laboratory, it does not have large-scale industrial uses, unlike the other hydrogen halides. Commercially, it is usually made by reacting iodine with hydrogen sulfide or hydrazine:
At room temperature, it is a colourless gas, like all of the hydrogen halides except hydrogen fluoride, since hydrogen cannot form strong hydrogen bonds to the large and only mildly electronegative iodine atom. It melts at −51.0 °C and boils at −35.1 °C. It is an endothermic compound that can exothermically dissociate at room temperature, although the process is very slow unless a catalyst is present: the reaction between hydrogen and iodine at room temperature to give hydrogen iodide does not proceed to completion. The H–I bond dissociation energy is likewise the smallest of the hydrogen halides, at 295 kJ/mol.