Is carbon dioxide in the human body dangerous? How much carbon dioxide is present in human blood?
A. Carbon dioxide, a waste product of respiration, is normally present in body tissues. Blood carries carbon dioxide from the body tissues to the lungs, where it is exhaled (and where the blood is reoxygenated from fresh, inhaled air). According to the text “Biology” by Claude A. Villee (copyrighted 1957 by W.B. Saunders Company, Philadelphia and London), each liter of blood transports about 50 milliliters of blood from body tissues to the alveoli of the lungs. To give you an idea of the relative amounts of carbon dioxide in various parts of the body, the partial pressure of carbon dioxide in body tissues is about 60 mm of mercury, about 47 mm in blood in veins, about 41 mm in blood in arteries, and about 35 mm in the alveoli. Acidosis occurs when the removal of carbon dioxide from the blood is restricted (as in pneumonia); tissue death can result.
