A lot of things, it turns out. But the one you'd probably least expect? Waste from a non-nuclear power plant, by a factor of 100 . Would we feel different about fossil fuels if this warning were mandatory on coal-fired power plants? Image courtesy Torsten Henning, Public Domain On Wednesday, we published a Physics+ article about radiation, written in memory of the bombing of Hiroshima, 70 years prior. While the author did a fantastic job in describing the state of the art on low-dose radiation research, I was troubled by a line where he cited "widespread deployment of nuclear power" along with medical scans and air travel as a potential contributor to chronic low-dose radiation. I took issue with the line because, counterintuitive as it might be, widespread deployment of nuclear power is acting to decrease the radiation burden of the average individual. To understand how, we'll need a smidge of radiation biophysics knowledge, along with a touch of nuclea