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NH Environmental Public Health Tracking Program
Carbon Monoxide

Carbon monoxide, or CO, is a toxic gas that is invisible and odorless. Breathing high levels of CO can cause severe illness or death in a matter of minutes. All people and animals are at risk for CO poisoning. Certain individuals, such as unborn babies, infants, and people with chronic heart disease, anemia, or respiratory problems, are more susceptible to its effects. Every year thousands of people across the U.S. seek medical care for non-fatal CO poisoning. Survivors of severe poisoning may suffer long-term neurological problems.

Even though unintentional CO poisoning can almost always be prevented, more than 400 Americans die every year as a result of it. Furthermore, the New Hampshire Carbon Monoxide Working group reports that several deaths occur in the State every year due to carbon monoxide poisoning caused by malfunctioning or improperly used fuel-burning furnaces, stoves, or appliances.

Breathing carbon monoxide can cause headache, dizziness, and nausea. If CO levels are high enough, loss of consciousness or sudden death may occur. For an explanation of how CO poisoning happens, visit the Centers for Disease Control and Prevention website.

Exposure and Risk

Exposure to moderate and high levels of CO over extended periods of time has also been linked with an increased risk of cardiovascular disease (CVD).

The health effects of long -term exposure to low levels of CO are less well understood. Better tracking of CO poisoning and exposure may provide opportunities to learn about the effects of low-dose exposures.

CO is given off whenever fuel or other materials are burned. People may be exposed to unsafe levels of CO as the result of:

Reduce Your Risk


To Learn More About Carbon Monoxide

Environmental Public Health Tracking Program
NH Department of Health and Human Services, Division of Public Health Services
29 Hazen Drive, Concord, NH 03301
Tel: (603) 271-4988 800-852-3345 ext.4988

copyright 2009. State of New Hampshire