That’s a question on many people’s minds as Japan struggles to maintain control of several nuclear reactors damaged by the recent tsunami. As the crisis continues Japanese officials have evacuated hundreds of thousands of people and are urging others to remain indoors. They are also reported to have begun handing out pills to residents who live close to the damaged plants. Here’s why.
In the event of a catastrophic meltdown and breach of containment, dangerous radioactive materials may be released into the surrounding community. One of the most significant health risks comes from radioactive forms of the element iodine, which can be taken up by the thyroid gland and cause cancers and other debilitating diseases. Children are the most vulnerable because their thyroid glands concentrate more iodine on a mass basis than adults and are more sensitive to radiation. A 30-fold increase in thyroid cancer in the former Soviet Union — about 4,000 excess cases — has been directly attributed to exposure to radioiodines released during the Chernobyl reactor fire. Aside from acute radiation poisoning suffered by the emergency responders and severe and widespread psychological effects among the general population, thyroid cancers are the only firmly established health effect to have resulted from the worst nuclear disaster in history.
In contrast to other harmful radioactive products that may be released from a nuclear plant, there actually is a drug that can protect people from thyroid damage. And it is so safe that it’s sold without prescription in local drugstores and on the Internet. Potassium iodide, a simple salt also known by its chemical symbol KI, protects the thyroid gland by flooding it with stable iodine so that the gland cannot take up the radioactive form. Despite the elevated levels of radioiodines detected in Poland after the Chernobyl accident, no additional cases of thyroid diseases occurred there because the Polish government distributed 18 million doses of the drug in a timely manner with almost no serious adverse health effects.
Timing of KI distribution is critical because if administration is delayed by only four hours after exposure, its effectiveness is cut in half. This fact has significant policy implications because it suggests that local governments should stockpile the drug in the local community rather than rely on regional and federal stockpiles that might take days to reach the affected population. The issue of how many doses should be available and how to get them to people in time are also the subject of debate. After Chernobyl, the highest incidence of excess thyroid cancers occurred more than 15 miles away, whereas U.S. policy considers people within a 10-mile radius to be the most vulnerable.
After the Sept. 11, 2001, attacks, when the vulnerability of power plants to terrorism was being closely examined, Congress changed the law to require the federal government to make KI available out to 20 miles around a plant. But both the Bush and Obama administrations have refused to implement the law, instead arguing that KI is a distraction from more effective measures, such as sheltering in place and control of the food supply. But what’s the first thing you would think to do if you heard that the local power plant was spewing radiation? Probably pack a few things, load the kids into the car and head out of Dodge. Anyone who was in the Houston area during Hurricane Rita will understand the flaw in presuming people can quickly evacuate a danger zone during a crisis. While evacuees are sitting in their car inching along the highway with all their fellow citizens, potassium iodide could be protecting them and their children from potential exposure.
Should you go out and buy some KI right now? No! There is no indication that significant amounts of radioactive iodine have been released in Japan. Even if radioiodine is released from the Japanese reactors, the radiation would quickly get diluted as it travels across the big ocean that separates us. In addition, while it is very safe, KI might not be right for you if you’re over 40 or have certain pre-existing conditions, including iodine allergy. Finally, I am dismayed by news reports indicating that the mad scramble to obtain KI by people who have no legitimate need for it may be contributing to a global supply problem. So take a deep breath of non-radioactive air and save the KI for the Japanese who might actually need it.
Kristen Kulinowski, Ph.D., is the executive director for education and public policy at Rice University’s Center for Biological and Environmental Nanotechnology. She worked on legislation for the Bioterrorism Act of 2002 that expanded the radius around U.S. nuclear power plants to which the radioprotective drug potassium iodide is available.