Bananas Are Naturally Radioactive

Bananas contain about 15 becquerels of radiation due to naturally occurring potassium-40. This has led scientists to create the 'Banana Equivalent Dose' (BED) as an informal measurement of radiation exposure. To put this in perspective, you'd need to eat about 10 million bananas in one sitting to receive a fatal dose of radiation. Airport security systems are so sensitive that they can detect the radiation from bananas, and large shipments of bananas have actually triggered radiation alarms at ports.