Question: What if oxygen is a really poisonous gas but it takes a long time to kill us? ???

Hannah Bolt answered on 11 Nov 2016:

Hi Dankus Memus,

As with many things in life, too much oxygen can indeed be a bad thing and poisonous! If we breathe in too much oxygen we can get something called ‘hyperoxia’ where we have an excess of oxygen in our body (for example in our tissues). Hyperoxia can kill humans very quickly if it isn’t treated!

If we breathe more oxygen than normal it can damage our cell membranes or might cause airsacs in our lungs (called alveoli) to collapse. If we breathe in too much oxygen at pressures greater than atmospheric pressure (for example, deep sea divers) it can cause problems with the central nervous system and might cause a seizure. Divers in the sea that use compressed air to breathe have to be very careful and must have special training to make sure that they stay safe.

However, the amount of oxygen in the atmosphere that we breathe in everyday is absolutely fine 🙂

Hannah