Blood is extremely dangerous when carried to the blood via the lungs by inhalation, because carbon monoxide irreversibly binds to hemoglobin to form carboxyhemoglobin, so that less hemoglobin is free to bind oxygen, and fewer oxygen molecules can be transported throughout the blood. This can cause suffocation insidiously. A fire burning in an enclosed room with poor ventilation presents a very dangerous hazard, since it can create a build-up of carbon monoxide in the air. Some carbon monoxide binds to hemoglobin when smoking tobacco. Blood for transfusion is obtained from human donors by blood donation and stored in a blood bank.
Oxygen–hemoglobin dissociation curve it influences intracellular pH due to formation of bicarbonate ion. Formation of carbaminohemoglobin stabilizes T state hemoglobin by formation of ion pairs. Only about 5–10% of the total CO content of blood is transported as carbamino compounds, whereas (80–90%) is transported as bicarbonate ions and a small amount is dissolved in the plasma.The formation of a bicarbonate ion will release a proton into the plasma, increasing acidity which also shifts the curve to the right as discussed above; low CO levels in the blood stream results in a high pH, and thus provides more optimal binding conditions for hemoglobin and