Radioactivity
Ahh, radioactivity and radioactive materials. The common origin of Daredevil and the Teenage Mutant Ninja Turtles, and a hazard we're shockingly casual with. Of course, we know that Atomic Gardening has the potential to save the world, but maybe shoe store x-rays are too far. Nuclear power and its byproducts is one of those really-good-or-really-bad things, which means that while it's cool your dentist can take good x-rays now, maybe it's not cool that the Museum of the Grand Canyon had buckets of uranium lying around.