Recent events in Japan, along with the pervasive terrorist threat of “dirty bombs” loaded with radioactive material, have brought radiation sickness — its detection and treatment — to the world’s center stage.
Attacking radiation sickness requires the same diagnostic and treatment developments that have helped us deal with other illnesses. Diabetics, for instance, have access to sophisticated blood glucose monitors and insulin. Used properly, these tools can significantly mitigate or stall the ravages of diabetes. Unfortunately, in the realm of radiation sickness, such advanced diagnostic and treatment options are not yet available.
“Those Geiger counter-style monitors used on power-plant workers in Japan detect contamination on clothing or skin that might not enter the body, not what the body has absorbed,” says medical physicist David Brenner, director of Columbia’s Center for Radiological Research. The treatment of radiation poisoning — lots of fluids, infusions of blood-clotting platelets, and infection-fighting antibiotics — has not changed for years. Doses of potassium iodide can protect against future thyroid cancer by shielding the thyroid from one type of fallout, radioactive iodine, but there are no effective methods for preventing the skin burns, damage to the bone marrow and gastrointestinal tract that are the hallmark of acute radiation poisoning. Nor is there an effective means for reducing the chronic effects of radiation exposure such as non-thyroid cancers and genetic mutations.
But there may be hope on the horizon. Dr. Brenner’s team has developed a way to detect early, DNA-based signs of radiation damage that estimates absorbed radiation by using a drop of blood like diabetics use to test their blood sugar. His new product is called RABiT (rapid automated biodosimetry tool) that can quickly measure the level of absorbed radiation from a bloodspot. Brenner says government approval is still a few years away, but that the prototype is available in the event of a widespread emergency.
Dr. Andrei Gudkov of the Roswell Park Cancer Institute has developed a drug named Flagellin that has been shown in monkeys to block cellular destruction from radiation and also to stimulate the recovery of damaged cells. The survival rate of the monkeys exposed to otherwise lethal doses of radiation was dramatically improved if they received Flagellin within two days of exposure. Bone marrow stimulating drugs such as Epogen and Neupogen (Amgen) have demonstrated theoretical efficacy for repairing the damage done to the marrow as a result of radiation exposure.
“There isn’t going to be a simple solution to any of this,” cautions Dr. Nelson Chao of Duke University, who is part of the school’s program to find resources to counteract the effects of radiation. “There will be a lot of little steps to address the plethora of toxicities that come from radiation.” Nonetheless, there does appear to be reason to remain optimistic that help may be on the way.
Photo by raneko.