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.
Glycated hemoglobin Glycated hemoglobin Glycated hemoglobin (hemoglobin A1c, HbA1c, A1C, or less commonly HgbA1c, haemoglobin A1c, HbA, Hb1c, etc.) is a form of hemoglobin that is bound to glucose. It is formed in a non-enzymatic glycation pathway by hemoglobin's exposure to plasma glucose. It is measured primarily to identify the three-month average plasma glucose concentration and thus can be used as a diagnostic test for diabetes and as assessment test for glycemic control in people with diabetes. The test is limited to a three-month average because the lifespan of a red blood cell is four months (120 days). However, since red blood