#1282: “EATING 600 BANANAS IS THE EQUIVALENT OF ONE CHEST X-RAYM IN TERMS OF RADIATION.”
Many of you must have heard some form of bananas being radioactive. This is in fact true. Bananas contain a radioactive element called potassium-40, which is not as scary as it sounds. The 40 attached to the name is because it is an isotope. By nature, an atom of any element must have an exact number of protons to be that element. However, the element can have a varying number of neutrons, changing its mass, hence the number at the end of the name (19 protons + 21 neutrons = 40). This can cause instability, and the atom needs to sweat off that excess energy either by releasing an electron, neutron, or proton (this case changes the element to a different one). This is what most know as radiation. So, is this case of radiation dangerous? Absolutely not. Take a look at yourself. Yes, you. You’re “radioactive” because the human body contains potassium, and the odds are stacked in favor of some of that potassium being potassium-40, so you can bet you have some excess electrons or neutrons or protons pew-pewing around in and out of you.
So, bananas. Turns out it’s just funny because they’re bananas. So much so that in the mid- nineties, an unofficial “Banana Equivalent Dose (BED)” measurement system for radiation emerged. Let’s stick with a better metric, though. Here is a chart from the XKCD guy, listing radiation does in Sieverts. I’ll include a link to the original image since it’s easier to read and very much worth the read.
Goddamn this guy sources well. Anyways, here we see a banana is equivalent to exposure of 0.1 microsieverts. A chest x-ray is 20 microsieverts. Let’s do the math. 20/0.1 = 200