So much better than a pro
- Dec 2, 2015
Ok, it looks like the definitions of poison take into account the dosage and the organism.Yeah, nah.
Oxygen. Kind of needed for our version of life. But too much also kills us. Our blood has evolved to capture the oxygen we breathe in and bind it safely to the haemoglobin transport molecule.If we breathe air with a much higher than normal O2 concentration, the oxygen in the lungs overwhelms the blood’s ability to carry it away. The result is that the excess oxygen binds to the surface proteins of the lungs - essentially they rust/burn. As, apparently, do the eyes and nervous system.
Not surprising really given oxygen is a highly reactive element.
Seems there's a case to be made that oxygen is poisonous but takes 3 score and ten (or somewhere there abouts) to do us in.
Trace metals. Iron, lithium, zinc, copper, chromium, nickel, cobalt, vanadium, molybdenum, manganese, etc. Very necessary for the correct functioning of our cells. Too much is toxic.
Probably a load more stuff like this.
Like chocolate is poisonous to dogs.
On the oxygen thing, might take a while. Apollo used 100% oxygen once in space. After the Apollo 1 fire during a test on the pad that killed 3 astronauts, they switched from 100% oxygen at 16psi to 60/40 Oxygen/Nitrogen at 16psi. But only on earth.
This changed after launch over 30 hours time to 100% Oxygen at 5 psi and remained that for the flight. So that's 7-12 days depending on the flight.
Skylab was 74% oxygen 26 nitrogen at 5 psi.
I think that Mir and the Space Shuttle used what the ISS uses. Very much like earth.
The International Space Station is 78%Nitrogen, 21% Oxygen. 14.7 psi Basically like earth sea level.