Because of the non-specific symptoms of headache, nausea and dizziness, carbon monoxide poisoning may not always be suspected. If carbon monoxide exposure occurs during sleep, coma and death may ensue. Carbon monoxide is produced when various fuels are burned. Because it has no odor, it's often difficult to detect. When released, this deadly gas can be inhaled into the lungs and diffused into the capillaries carrying red blood cells to all cells in the body. Each red blood cell contains numerous molecules of hemoglobin, which combine with oxygen. In the presence of carbon monoxide, oxygen has difficulty binding to hemoglobin. This reduces the delivery of oxygen to all the cells in the body. Organ dysfunction and death can result.