Carbon monoxide is one of the most highly toxic gasses, which can cause some serious health problems or even death pretty easily. It is dangerous because it does not have any odor taste or color and it is not even noticeable during the initial stage, which is why a person moves closer to death and does not even realize it. When carbon monoxide enters the body it mixes with hemoglobin, which eventually forms carboxyhemoglobin. When it is formed it stops the oxygen and hemoglobin from binding with each other resulting in hypoxia. This brings down the capacity of blood to carry oxygen a great deal.