Why is carbon monoxide dangerous? What is the cause of carbon monoxide poisoning?

Carbon monoxide can be extremely dangerous because CO robs your blood of oxygen. When you inhale carbon monoxide, it bonds with the hemoglobin in your blood, displacing life-giving oxygen. This produces a toxic compound in your blood called "Carboxyhemoglobin" (COHb) which is the source of carbon monoxide poisoning. Over time, exposure to CO can make you feel sick or worse, victims exposed to sufficiently high levels of carbon monoxide can suffer brain damage, or even die. According to the Journal of the American Medical Association (JAMA), 1500 people die each year because of carbon monoxide poisoning, and another 10,000 become ill. Carbon monoxide is dangerous since you can't see, smell, or taste the gas. Because you can't sense it, carbon monoxide can poison you before you even know it's there.