Toxic gasses

• Carbon Dioxide there is a surprising amount of misinformation about CO2. It does not cause asphyxiation, it is actually toxic. Asphyxiation is caused by lack of oxygen in the ambient air being inhaled. But even if there is ample oxygen in the air, a high concentration of CO2 is still toxic. This is because it reduces the ability of hemoglobin in red blood cells to carry oxygen. On the Apollo 13 lunar mission the crew had to modify CO2 filters from the Command Module to operate in the Lunar Module. The filters used Lithium Hydroxide (LiOH) to remove the exhaled CO2 from the ambient air.