In a circular dated November 14, 2004, the Ministries of the Interior and Health implemented a new system for monitoring carbon monoxide poisoning through the establishment of regional working groups tasked with leading and coordinating efforts to address poisoning at the regional level. In the Pays de la Loire region, this working group is led by the DRASS’s Health and Environment Department, with the epidemiological analysis of data and the annual preparation of the regional surveillance report entrusted to the CIRE. This report provides an assessment of the first year of implementation of the new surveillance system. It highlights the system’s operation, the scale of the public health problem, medical care, as well as the circumstances and risk factors in the home. (BDSP Summary)