In Île-de-France, where carbon monoxide (CO) poisonings were among the most common in 2008, a heating boiler was responsible for two-thirds of poisoning cases, and the improper use of outdoor heaters or barbecues accounted for one in ten poisonings. The purpose of this article is to determine whether these characteristics of poisoning cases occurring in Île-de-France were still observed in 2010 and to describe the individuals affected. With incidence rates varying from one department to another, 284 cases were reported in 2010. Occurring very frequently in the home (83.7%), the appliance involved was most often a boiler (65.6%). A malfunction of this appliance was often identified (31.0%), but a defect in the combustion gas connection or exhaust ducts was nevertheless very common (69.0%), with this defect potentially associated with inadequate ventilation in the home (21.4%). The improper use of braziers or barbecues indoors caused 20 (10.4%) cases of poisoning, 11 of which were reported in Seine-Saint-Denis. Severe cases accounted for 8.3% of the 895 people poisoned, and 7 deaths were reported. The stable and high frequency of poisonings caused by boilers demonstrates that annual maintenance of these appliances and their flue gas exhaust ducts is essential. Furthermore, raising awareness among a segment of the population regarding the risks of improper use of portable heaters or barbecues is necessary. (R.A.)