Stan,
First off, there are some organisms, I forgot if they are bacteria or fungi, or maybe both, you can google and find out, but there are organisms that were found in highly acidic effluents from active volcanos.
Ah, there, found some examples, but there's more.
https://www.forbes.com/sites/robina...bility-of-life-inside-a-volcano/#30c484e51c1d
http://www.bitsofscience.org/extremophile-bacteria-archaea-volcano-6094/
http://all-geo.org/volcan01010/2014...-microbes-to-colonise-the-fimmvorduhals-lava/
https://www.newscientist.com/articl...es-discovered-on-volcano-soon-after-eruption/
Second, a professor of human psychology, I'm told, used to make his students go thru this experiment: they would take glasses right out of the dishwasher, or, when the classroom was bigger, distribute brand new disposable cups to the students.
The students were told to fill the cups with water and take a couple of sips. "All good?" he would ask. Everyone nodded yes. "Spit in the cups", he'd tell them, and they would. "Now drink the water", he'd say.
Very few people did. Most people were grossed out.
By their own spit, which was inside their own mouths just a couple of seconds before.
A few questions that have been asked, in addition to the question asked by the original poster, and people dodged answering them.
Would you eat food cooked in a stainless-steel pot or aluminum pot
with the same "patina" as a cast-iron pot? Or would you think the homemaker was subpar?
If it's not bad, why do we bother to wash all the other pots then? If the other pots *need* to be *cleaned*, why don't we clean cast-iron?
Now, going into a slightly different but related question: if the pot was soiled with mouse poo, or a bunch of mud or barn "junk", would you just chuck it into a roaring fire for an hour, wait for it to cool off, brush off the ashes and cook in it right away?
Or would you be too grossed out unless it was *washed* and *rinsed*?
There is no right or wrong answer here. One person feels it's "safe" and "clean enough" and the next person won't touch it until it has been cleaned and sterilized multiple times.
Sterile doesn't imply clean. One could dump ashes from a crematorium inside cast iron, brush it off, and I wonder how many people here would use that pot without washing? It's as sterile as it could be. It's still dirt, and it makes things it touches dirty. To me and many others anyway.
How about the rest of you? (No pun intended.)