These materials include low-grade waste from power stations and small devices containing radioactive materials such as cesium-137, used in some cancer treatments, cobalt-60, used in food irradiation, or americum, incorporated in sensors for oil exploration.

ECONOMIST: How dirty bombs are made, and what they can do

The Ag Department should finalize irradiation rules right now, thereby saving lives and preventing needless outbreaks of food poisoning.

FORBES: Fact and Comment