The Union Cycliste Internationale (UCI) announces that it will propose to its Management Committee that the use of carbon monoxide (CO) by riders be banned for medical reasons. The decision will be made by the Federation's executive body at its next meeting, which will be held in Arras, France, on January 31 and February 1, 2025.

Carbon monoxide is a toxic and odorless gas that is often the cause of domestic accidents. Inhaled in low doses and under strict safety conditions, the gas is used in medicine as a tracer to measure lung oxygen diffusion or total hemoglobin mass. However, if inhaled repeatedly under non-medical conditions, it can cause side effects such as headaches, fatigue, nausea, vomiting, chest pain, breathing difficulties, and even loss of consciousness.

The UCI believes that these health side effects and the complete lack of knowledge about the long-term effects of repeated carbon monoxide inhalation justify banning the use of this gas for medical reasons. Its use in medical settings, by qualified medical personnel and in the rigorous context of total hemoglobin mass assessment, would nevertheless remain authorized.