What immediate danger does carbon monoxide from cigarette smoke pose?

Carbon monoxide, a colorless and odorless gas produced by incomplete combustion, poses a significant immediate danger primarily because it inhibits the blood's oxygen-carrying capacity. When carbon monoxide is inhaled, it binds to hemoglobin in red blood cells more effectively than oxygen does, forming carboxyhemoglobin. This reduces the amount of hemoglobin available to carry oxygen throughout the body, leading to tissue hypoxia—a state where tissues do not receive enough oxygen.

As a result, even if a person is breathing normally, their body can suffer from lack of oxygen, which is particularly dangerous during activities that require increased oxygen levels, such as flying an aircraft. Symptoms of carbon monoxide exposure may not be immediately apparent, yet the impairment of oxygen delivery can quickly lead to serious consequences including loss of consciousness or impaired cognitive functions which can adversely impact performance and safety, especially in aviation contexts. Understanding this mechanism is critical for recognizing the risks associated with carbon monoxide exposure from cigarette smoke and promotes the importance of maintaining good ventilation and avoiding smoking in confined spaces.