Carbon monoxide

The primary health effects associated with overexposure to CO appear to be related to the condition of hypoxia or oxygen deprivation. Carbon monoxide combines with the hemoglobin (Hb) of the blood to form carboxyhemoglobin (COHb). This action interferes with the oxygen-carrying capacity of the blood and the tissues experience the condition of hypoxia. The initial effects of overexposure to CO may include a throbbing headache and dyspnea upon exertion, tachypnea and lethargy. This may be followed by dizziness, nausea, vomiting, weakness, tachycardia and hyperventilation. During more severe exposures, the victim may show electrocardiogram (ECG) changes suggestive of cardiac ischemia (heart attack), atrial or ventricular arrhythmias, visual field deficits, confusion, syncope, coma, seizures, respiratory failure and death.