Carbon monoxide emissions in the European Union (EU-27) 1990-2021
Carbon monoxide (CO) emissions in the European Union (EU-27) increased 4.7 percent in 2021,to 17.7 million metric tons. Since 1990, EU-27 CO emissions have fallen roughly 70 percent. Improvements to transportation sector efficiency, such as the installation of catalytic converters to vehicles, have contributed greatly to CO reductions throughout the EU-27.