Carbon monoxide concentrations, 1996–17

Carbon monoxide (CO) is a gas formed by the incomplete combustion of fuels, particularly from motor vehicles, from burning wood and coal, and using unflued gas heaters for home heating. It also occurs naturally; for example, from wild fires.
Carbon monoxide can affect human health by interfering with the blood’s ability to carry oxygen and by aggravating heart conditions. It has a relatively long life in the atmosphere – about three months. This is due to the slow rate at which carbon monoxide oxidises, forming carbon dioxide (a greenhouse gas). Carbon monoxide also has an important role in forming smog.
More information on this dataset and how it relates to our environmental reporting indicators and topics can be found in the attached data quality pdf.