Potassium iodide prophylaxis: what have we learned and questions raised by the accident at the Fukushima Daiichi Nuclear Power Plant.

There is no doubt that when potassium iodide (KI) is administered in a timely fashion, much of the potential exposure to radioactive iodine isotopes from an atmospheric release can be safely averted (1–3). The United States of America Food andDrug Administration (FDA) and theWorld Health Organization (WHO), among others, have established guidelines for the use of KI in these settings (4,5). Legislation in the United States requires all areas within a 20-mile (32-km) radius of a nuclear power plant (NPP) to have KI-related policies and hasmade it possible for affected states to obtainKI from federal sources. Executive action during the recent Bush administration reduced the radius to 10 miles (16 km). Nevertheless, the current status is a vast improvement over what it was before the American Thyroid Association (ATA) and its members began advocating for change (6). The ATA has continued concerns about the KI distribution policy of the United States, especially in two areas, as expressed in the March 30, 2011, letter from the ATA to Dr. John P. Holdren, Director of Office of Science and Technology Policy (7). One concern is that the decision of whether to store KI at sites where it is intended to be distributed (known as ‘‘predistribution’’) is left to the individual states. The position of the ATA, which it has vigorously advocated in the United States, is that there should by universal predistribution of KI to households and other key locations in the vicinity of NPPs. Second, the ATA advocates that the area of predistribution should be extended from the current 10-mile radius around NPPs to a radius of 50 miles (80 km) around NPPs. Given the events in Fukushima 1 year ago, it is appropriate to evaluate the ATA’s position and ask if it should be altered, enhanced, and/or affirmed with renewed vigor.