Biology Stack Exchange is a question and answer site for biology researchers, academics, and students. It's 100% free, no registration required.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

Other than CO₂ and Methane what other gases do humans produce or emit?

For example, does skin decomposition, or aerobic respiration emit any special gases that people don't normally realize or know about.

share|improve this question
A discovery I made during research is that while being poisonous to the central nervous system, methanol is a natural endogenous compound found in normal, healthy human individuals. One study found a mean of 4.5 ppm in the exhaled breath of the subjects. – Gabriel Fair Nov 19 '15 at 3:31

The gases NO, H₂S, CO even have a function in the human body!

Nitric oxide is produced in endothel and neurons as messenger, and in macrophages as cause of nitrosative stress for imprisoned bacteria. Hydrogen sulfide is produced in cysteine catabolism and functions as messenger (only recently discovered). Carbon monoxide appears to act as messenger, too.

Wu, L; Wang, R (December 2005). "Carbon Monoxide: Endogenous Production, Physiological Functions, and Pharmacological Applications". Pharmacol Rev 57 (4): 585–630. doi:10.1124/pr.57.4.3. PMID 16382109

share|improve this answer
I always understood that NO, when used as a neurotransmitter / second messenger, is in solution, i.e. not gaseous. – Konrad Rudolph Aug 15 '12 at 21:01
Would these gases be extreated from the body in gasous form? – Gabriel Fair Jun 9 '15 at 22:21

H₂O is emitted through respiration and perspiration.

share|improve this answer

In addition to the comment above, nitric oxide main function is to cause erection in male sexual part. Nitric oxide causes blood to be clotted in soft tissue of penis.

share|improve this answer
Clotting does not occur in that situation, please check a reliable source and update your answer. – jonsca Oct 6 '12 at 23:35

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.