If we inhale air to get oxygen and exhale carbon dioxide, why is oxygen by itself deadly?

Question

And do they put carbon dioxide inside those oxygen tubes?

In: 0

Answer 1

That’s not quite correct, you’re missing some context. Oxygen by itself is not “deady,” it becomes toxic at higher pressures. The air we breath is 21% oxygen. At sea level, air pressure is 1013.25 millibar. That means at sea level, the partial pressure of oxygen is is 213 millibar. You could breathe 100% pure oxygen at 213 millibar 24/7 for the rest of your life and be fine because that’s the same partial pressure of oxygen as you breathe in air. If you were to breathe 100% pure oxygen at a higher pressure, say sea level pressure of 1013.25 millibar, then it becomes toxic.

I’m not sure what you mean by “those oxygen tubes.” Are you talking about air cylinders? Nasal cannula? Regardless, the answer is no, why would there be added CO2? CO2 is toxic. that’s why we exhale it.