How many times greater is carbon monoxide's affinity for hemoglobin compared to oxygen?

Carbon monoxide (CO) has an exceptionally high affinity for hemoglobin, which is about 210 times greater than that of oxygen. This strong binding is due to the molecular structure of carbon monoxide, which allows it to insert itself into the heme group of hemoglobin in a manner that is significantly more stable than the bond formed with oxygen.

Because hemoglobin normally carries oxygen from the lungs to the tissues, carbon monoxide’s higher affinity severely disrupts this process. When CO binds to hemoglobin, it not only occupies the binding sites that would typically hold oxygen but also alters the structure of hemoglobin in a way that restricts the delivery of oxygen to body tissues. This is why exposure to carbon monoxide can lead to serious health risks, as the body is effectively deprived of the vital oxygen it needs to function.

Understanding this affinity is crucial in fields such as medicine and environmental health, where carbon monoxide exposure can have dire consequences, and quick recognition of its effects can lead to timely intervention.